Today, let’s take a closer look at the results of the desulfurization lab scale results featured in a previous
post.
As you will recall, the Google® search string desulfurization AND "lab scale" resulted in 128,000 results
As far as I can tell, “bench scale” and “lab scale” seem to be interchangeable in re: the Technology Readiness scale. However, since some people use the term “bench scale,” while others use the term “lab scale,” it is best to search on both terms.
We will browse the results to see what we can find that fits into anything from 2 to 7 on the Technology Readiness scale.
See today’s tip at the end of this post.
As you will recall, the Google® search string desulfurization AND "lab scale" resulted in 128,000 results
As far as I can tell, “bench scale” and “lab scale” seem to be interchangeable in re: the Technology Readiness scale. However, since some people use the term “bench scale,” while others use the term “lab scale,” it is best to search on both terms.
We will browse the results to see what we can find that fits into anything from 2 to 7 on the Technology Readiness scale.
See today’s tip at the end of this post.
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2
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validated concept
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experimental proof of concept using
physical model tests
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3
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prototype, prototype tested
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system function, performance and
reliability tested
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4
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environment tested
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preproduction system environment tested
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5
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system tested
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production system interface tested
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6
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Reid qualified, system installed
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production system installed and tested
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7
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field proven
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production system field proven
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Google® search string:
desulfurization AND bench
///////
RESULTS (browsing and selecting 5 pages deep)
7th European Meeting on Chemical Industry and Environment EMChIE 2015
Modelling biotrickling filters to minimize elemental sulfur accumulation during biogas desulfurization under aerobic conditions
L.R. López.1, A.D. Dorado 2, M. Mora1, Ll. Prades 2, X. Gamisans2, J. Lafuente1, D. Gabriel1
1 Universitat Autònoma de Barcelona, Department of Chemical Engineering, Escola d’Enginyeria, 08193 Belleterra, Spain.
2 Universitat Politécnica de Catalunya, Department of Mining Engineering and Natural Resources, Bases de Manresa 61-73, 08240 Manresa, Spain.
e-mail: luisrafael.lopez@uab.cat
Abstract
A mathematical dynamic model describing biological removal of high loads of H2S from biogas streams through a biotrickling filter (BTF) was developed, calibrated and validated to a range of specific experimental conditions of a lab-scale BTF. This model takes into account the main processes occurring in the three phases of the desulfurizing BTF (gas, liquid and biofilm phase) in a co-current configuration flow mode. This model attempts to describe accurately intermediate products obtained from H2S oxidation using kinetic models, previously developed using respirometric techniques with biomass samples obtained from the same BTF set up used here. Previous to the model parameters calibration, a sensitivity analysis was performed in order to focus the parameters estimation on those parameters that showed a highest influence on modelling results over the main process variables. To calibrate the model, an objective function considering the difference between the experimental and the predicted data was minimized. Experimental data for model calibration corresponded to a period of 5 days of operation of the BTF under stepwise increasing H2S concentrations between 2000 and 10000 ppmv. Once the model was calibrated, model was validated by simulating a period of 2 months of operation of the BTF at an average concentration of 2000 ppmv. Validation was successfully achieved since the model also described the reactor performance during a pseudo steady-state period.
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URL
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Hot-Gas Desulfurization with Sulfur Recovery
Jeffrey W. Portzer (jwp@rti.org; 919-541-8025)
Ashok S. Damle (adamle@rti.org; 919-541-6146)
Santosh K. Gangwal (skg@rti.org; 919-541-8033)
Research Triangle Institute, Research Triangle Park, NC 27709
Introduction
Advanced integrated gasification combined cycle (IGCC) power plants require advanced particle filters and hot-gas desulfurization (HGD) following gasification in order to achieve high thermal efficiency. The Federal Energy Technology Center’s (FETC’s) research program is focusing on the development of regenerable metal oxide sorbents, such as zinc titanate, for efficient removal of hydrogen sulfide (H2S) from coal gas. During regeneration of these sorbents, there is the opportunity to produce elemental sulfur (Sx) as a valuable byproduct. Currently, the leading technologies use air or dilute-air regeneration of the sorbents to produce a tail gas containing mostly nitrogen plus 2 to 14 vol% sulfur dioxide (SO2). This tail gas must be treated further to avoid release of SO2. One option is the catalytic reduction of SO2 with a coal gas slipstream using the Direct Sulfur Recovery Process (DSRP), a leading first- generation technology to produce elemental sulfur. The FETC is sponsoring the development of the DSRP (Dorchak et al., 1991; Portzer and Gangwal, 1995), a single-step catalytic process that uses the reducing components (H2 and CO) of coal gas to directly and efficiently reduce the SO2 to elemental sulfur: SO2 + 2H2 (or 2CO) 2H2O (or 2CO2) + 1/nSn . In the DSRP, for every mole of SO2, two moles of reducing gas are used, leading to a small but noticeable consumption of coal gas. Although the DSRP continues to show promise and has undergone field testing at gasifier sites (Portzer et al., 1996), alternative or improved processing is still possible.
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URL
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A complete model of a biotrickling filter for biogas desulfurization recently published in Chemical Engineering Journal
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URL
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Abstract
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This
new work developed by the GENOCOV and TRAGASOL research groups comes to fill
an existing gap in the field. Literature available for H2S biotrickling
filters modeling is scarce and a model describing properly the removal of
high loads of H2S in biotrickling filters was still lacking in literature.
Previous models for H2S removal in biotrickling filters focused on removal of
H2S at odor level concentrations while only few models in literature dealt
with high loads of H2S. In this work A dynamic model describing
physical-chemical and biological processes for the removal of high loads of
H2S from biogas streams in biotrickling filters (BTFs) was developed,
calibrated and validated for a wide range of experimental conditions in a
lab-scale BTF. The model considers the main processes occurring in the three
phases of a BTF (gas, liquid and biofilm) in a co-current flow mode configuration.
Furthermore, this model attempts to describe accurately the intermediate
(thiosulfate and elemental sulfur) and final products (sulfate) of H2S
oxidation. A sensitivity analysis was performed in order to focus parameters
estimation efforts on those parameters. Experimental data used corresponded
to the operation of the BTF for H2S concentrations between 2000 and 10000
ppmv. The model described the reactor performance in terms of H2S removal and
predicted satisfactorily the main intermediate and final products produced
during the biological oxidation process.
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Website
Title
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BTP-GO
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A Review on Desulphurization of Liquid Fuel by Adsorption
International Journal of Science and Research (IJSR)
Pratibha R. Gawande1, Dr. Jayant P. Kaware2
1Datta Meghe College of Engineering, Airoli, Navi Mumbai, Maharashtra, India,
2Bhonsla College of Engineering & Research, Akola, Maharashtra, India
Abstract: Sulfur compounds create impurities in the liquid oil. Because of the requirement for low sulfur content of fuel oils, it is necessary to develop methods for removal of sulphur from liquid oil. Adsorption is widely used to remove sulphur from liquid fuel. The Sulphur removal from liquid fuel by adsorption is very important area of research. Many researchers have done their research on this area. This review paper presents the idea about the removal sulphur from liquid fuel by various researchers. Adsorption is one of the easily and fast method to remove sulfur from liquid fuel.
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Author
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Pratibha
R. Gawande
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Author
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Jayant
P. Kaware
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URL
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Volume
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3
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Issue
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7
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Pages
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2255–2259
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Publication
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Int.
J. Sci. Res
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Date
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2014
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Autothermal reforming of n-dodecane and desulfurized Jet-A fuel for producing hydrogen-rich syngas
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Author
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Xinhai
Xu
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Author
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Shuyang
Zhang
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Author
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Peiwen
Li
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URL
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Volume
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39
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Issue
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34
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Pages
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19593-19602
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Publication
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International
Journal of Hydrogen Energy
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Date
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2014
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Abstract
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Catalytic
reforming is a technology to produce hydrogen and syngas from heavy
hydrocarbon fuels in order to supply hydrogen to fuel cells. A lab-scale 2.5
kWt autothermal reforming (ATR) system with a specially designed reformer and
combined analysis of balance-of-plant was studied and tested in the present
study. NiOeRh based bimetallic catalysts with promoters of Ce, K, and La were
used in the reformer. The performance of the reformer was studied by checking
the hydrogen selectivity, COx selectivity, and energy conversion efficiency
at various operating temperatures, steam to carbon ratios, oxygen to carbon
ratios, and reactants' inlet temperatures. The experimental work firstly
tested ndodecane as the surrogate of Jet-A fuel to optimize operating
conditions. After that, desulfurized commercial Jet-A fuel was tested at the
optimized operating conditions. The design of the reformer and the catalyst
are recommended for high performance Jet-A fuel reforming and hydrogen-rich
syngas production.
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Circulating Regeneration and Resource Recovery of Flue Gas Desulfurization Residuals using a Membrane Electroreactor: From Lab Concept to Commercial Scale
|
Author
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Chenglei
Yang
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Author
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Ying
Hu
|
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Author
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Limei
Cao
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Author
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Ji
Yang
|
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URL
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Volume
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46
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Issue
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20
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Pages
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11273-11279
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Publication
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Environmental
Science & Technology
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Date
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October
16, 2012
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Abstract
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Desulfurization
residuals (using NaOH sorbent) were regenerated electrochemically, and at the
same time sulfur in the flue gas was recovered as H2SO4 and H2 was produced
as a clean energy. Since industrialization should always be the final goal to
pursue for lab technologies and the evolution of pilot- and full-scale
commercial reactors has taken place relatively slowly, this paper is aimed to
develop an electroreactor on a sufficiently large scale to evaluate the
application potential of the proposed regeneration process. The following key
design parameters are discussed: (1) voltage distributions over electrode, membrane,
and electrolyte; and (2) scaling up correlation based on lab-scale reactor
operation parameters. Thereafter, in the developed reactor, the
desulfurization residuals using NaOH sorbent from a semidry flue gas
desulfurization (FGD) facility of a power plant in Shandong Province were
regenerated and it is significant to note that the electrochemical efficiency
of the designed reactor is comparable to that of the chlor-alkali industry,
showing that the technology is environmentally friendly and economically
feasible. If this technology is to be employed for FGD, the facility could be
a profit-generating manufacturing part instead of a currently money-consuming
burden for the plants.
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Desulfurization and Autothermal Reforming of Jet-A Fuel to Produce Syngas for Onboard Solid Oxide Fuel Cell Applications
|
Type
|
Journal
Article
|
|
Author
|
Xinhai
Xu
|
|
URL
|
|
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Date
|
2014/01/01
|
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Abstract
|
Fuel
cell is one of the most promising clean energy and alternative energy
technologies due to its advantages of low emissions and high efficiency. One
application of the fuel cell technology is onboard auxiliary power units
(APUs) for power generation in aircrafts, ships, and automobiles. In order to
supply hydrogen or syngas for the fuel cell APUs, onboard fuel processing
technology was proposed to convert hydrocarbon fuels into syngas through
reforming reactions. Two major tasks need to be completed in onboard fuel
processing technology. Firstly sulfur compounds have to be removed from
hydrocarbon fuels because sulfur can cause reforming catalyst deactivation
and fuel cell electrodes poisoning problems. Secondly hydrogen and carbon
monoxide shall be produced by reforming of hydrocarbon fuels at a high energy
conversion efficiency. This dissertation focused on onboard fuel processing
of Jet-A fuel to produce hydrogen and syngas for solid oxide fuel cell (SOFC)
APUs. Jet-A fuel was studied because it is the logistic fuel commonly used
for civilian airplanes and military heavy duty trucks. Ultra-deep adsorptive
desulfurization of Jet-A fuel from over 1,000 ppmw to below 50 ppmw, and
autothermal reforming of n-dodecane as a Jet-A fuel surrogate as well as the
real desulfurized Jet-A fuel to produce syngas have been systematically
investigated in the present study. For the adsorptive desulfurization of
Jet-A fuel, a novel NiO-CeO₂/A1₂O₃-SiO₂ adsorbent was proposed and prepared
in-house for experimental tests. The sulfur adsorption kinetic characteristic
and isotherm at equilibrium were studied in batch tests, and the dynamic
desulfurization performance of the adsorbent was investigated in fixed bed
tests. Fixed bed tests operation conditions including liquid hourly space
velocity (LHSV), adsorbent particle size, and fixed bed dimensions were
optimized to achieve the highest adsorbent sulfur adsorption capacity. For
the reforming of Jet-A fuel, autothermal reforming (ATR) method was employed
and a bimetallic NiO-Rh catalyst was synthesized for the ATR reactions. A
lab-scale 2.5 kWt autothermal reforming system including the reformer and
balance-of-plant was designed, fabricated, integrated and tested. The
reforming system performances at various operation conditions were compared.
Reformer operation temperature, steam to carbon ratio and oxygen to carbon
ratio, as well as pre-heating temperatures for fuel, air and steam were
optimized based on system energy conversion efficiency, H₂ selectivity and
COₓ selectivity.
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Desulfurization of Jet A-1 and Heating Oil: General Aspects and Experimental Results
|
Type
|
Journal
Article
|
|
Author
|
Ralf
Peters
|
|
Author
|
Jochen
Latz
|
|
Author
|
Joachim
Pasel
|
|
Author
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Detlef
Stolten
|
|
URL
|
|
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Volume
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12
|
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Issue
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1
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|
Pages
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543-554
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Publication
|
ECS
Transactions
|
|
Date
|
05/02/2008
|
|
Abstract
|
Different
novel technologies have been screened for liquid phase desulfurization, i.e.
an extraction with ionic liquids, a fractional distillation, a membrane
separation, a selective adsorption and a novel hydro-desulfurization
technology (HDS). From lab-scale studies two desulfurization concepts were
developed, i.e. a concept for an improved HDS technology and a two-stage
concept. Before HDS the liquid fuel is externally saturated with syngas.
Related to commercial HDS no gas recycle is necessary. For the second concept
a light cut fraction is separated by distillation, while the heavy fraction
is led back to the aircraft's tank. The subsequent deep desulfurization is
realized by adsorption.
|
Desulfurization of natural gas for fuel cells
Ram Ramanan, Bloom Energy
Bloom’s systems run off of pipeline natural gas; before this gas enters the fuel cells it must be “desulfurized”. During this process sulfur and other harmful impurities must be completely removed from the gas stream. To do this, the gas is passed through a number of packed beds which have each been tailored to pick up these impurities. Each vessel is filled with sorbents that purify the gas through physisorption and/or chemisorption. We operate at near ambient temperature and less than 15psig of pressure.
Bloom is continuously working to improve the effectiveness of the desulfurization sorbent materials already in use and to qualify new sorbents for field use. Before putting any new materials in the field, we must first qualify them on a lab scale. These lab tests must be accelerated in order to obtain results quickly and also accelerated to keep the overall experiment costs low. Ideally these lab tests will enable us to compare the relative performance of two materials against each other. If for example, in a lab test, ‘Material A’ outperforms ‘Material B’, we expect ‘Material A’ must also outperform ‘Material B’ in the field. Since many factors impact how the materials will perform in the field (and since we cannot introduce each of these elements into our lab tests), we do not expect to have identical lab and field results; the relative performance of any two materials, however, should be same. We need to determine the best way to design a lab scale version of our large field vessels. Dimensions of the lab test beds (including diameter & length) will significantly impact the cost and results of the tests. Not all sorbents are the same size and shape; certain materials may have an advantage solely because of their size. Flow rate, contact time, and space velocity also need to be defined as each will impact the results of the lab tests.
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URL
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Experimentation, modelling and optimization of oxidative desulphurization of heavy gas oil: energy consumption and recovery issues
H.A. Khalfalla†, I.M. Mujtaba†, Mohamed M. ELGARNI‡, Hadi A. EL AKRAMI*
†School of Engineering Design & Technology, University of Bradford
Bradford BD7 1DP, UK.
‡ Libyan Petroleum Institute, P.O. Box 6431 Tripoli-Libya
* Chemical Engineering Al-Fateh University P.O. Box 13335 Tripoli Libya
Deep desulphurization of a model sulfur compound dibenzothiophene (DBT) and heavy gas oil (HGO) is studied with hydrogen peroxide (H2O2) as oxidant and formic acid (HCOOH) as catalyst using a lab-scale batch reactor. The results are quite promising and therefore a large scale oxidation process using a continuous stirrer tank reactor (CSTR) is considered further. Large amount of energy is required to carry out reaction at temperature same as the batch reactor, the recovery of which is very important for maximizing the profitability of operation and reducing environmental impact. Therefore we have proposed a heat integrated CSTR system. In the absence of a real plant we have developed a process model for the system. The kinetic model for the CSTR is based on the batch reactor experiments. An optimization problem to minimize the overall annual plant cost is formulated and solved using gPROMS. A cost saving of 36% for the integrated process is obtained compared to a non-integrated process.
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Type
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Journal
Article
|
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Author
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H.
A. Khalfalla
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Author
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I.
M. Mujtaba
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Author
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Mohamed
M. Elgarni
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Author
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Hadi
A. El-Akrami
|
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URL
|
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Volume
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11
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Pages
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53–58
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Publication
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Chemical
Engineering Transactions
|
|
Date
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2007
|
From Lab to Miniplant: Effective Process Development for Deep Desulfurization of Industrial Coke Oven Gas
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Type
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Journal
Article
|
|
URL
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|
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Publication
|
Proceeding:
2016 AIChE Annual Meeting
|
|
Date
|
2016
|
|
Abstract
|
As
a consequence of the energy revolution and the ambition to reduce emissions,
known and in chemical engineering established processes are adapted to
convert off-gas of steel plants to basic chemicals. An initial and therefore
crucial role in this plan is the development of a process that removes
organosulfur compounds from coke oven gas. This is necessary to treat this
valuable gas, that consists of approx. 60 vol.% hydrogen, 20 vol.% methane,
and 6 vol.% carbon monoxide, with catalysts that are highly sensitive to
sulfur (Twigg and Spencer 2001). In accordance with other desulfurization
processes (e.g., natural gas) heterogeneous catalysis in a fixed bed is
chosen to fulfil this task since it shows the highest conversion rates
compared to other processes. Here, an industrial catalyst is analyzed and
investigated for its potential to convert organosulfur compounds like COS or
CS2 to H2S which can consequently be removed from the gas by a scrubber or a
guard-bed (Rhodes et al. 2000):
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Full scale calcium bromide injection with subsequent mercury oxidation and removal within wet flue gas desulphurization system: Experience at a 700 MW coal-fired power facility
Berry, Mark Simpson
ProQuest Dissertations And Theses; Thesis (Ph.D.)--The University of Alabama at Birmingham, 2012.; Publication Number: AAT 3550315; ISBN: 9781267873651; Source: Dissertation Abstracts International, Volume: 74-05(E), Section: B.; 254 p.
The Environmental Protection Agency promulgated the Mercury and Air Toxics Standards rule, which requires that existing power plants reduce mercury emissions to meet an emission rate of 1.2 lb/TBtu on a 30-day rolling average and that new plants meet a 0.0002 lb/GWHr emission rate. This translates to mercury removals greater than 90% for existing units and greater than 99% for new units. Current state-of-the-art technology for the control of mercury emissions uses activated carbon injected upstream of a fabric filter, a costly proposition. For example, a fabric filter, if not already available, would require a 200M capital investment for a 700 MW size unit. A lower-cost option involves the injection of activated carbon into an existing cold-side electrostatic precipitator. Both options would incur the cost of activated carbon, upwards of 3M per year. The combination of selective catalytic reduction (SCR) reactors and wet flue gas desulphurization (wet FGD) systems have demonstrated the ability to substantially reduce mercury emissions, especially at units that burn coals containing sufficient halogens. Halogens are necessary for transforming elemental mercury to oxidized mercury, which is water-soluble. Plants burning halogen-deficient coals such as Power River Basin (PRB) coals currently have no alternative but to install activated carbon-based approaches to control mercury emissions. This research consisted of investigating calcium bromide addition onto PRB coal as a method of increasing flue gas halogen concentration. The treated coal was combusted in a 700 MW boiler and the subsequent treated flue gas was introduced into a wet FGD. Short-term parametric and an 83-day longer-term tests were completed to determine the ability of calcium bromine to oxidize mercury and to study the removal of the mercury in a wet FGD. The research goal was to show that calcium bromine addition to PRB coal was a viable approach for meeting the Mercury and Air Toxics Standards rule for existing boilers. The use of calcium bromide injection as an alternative to activated carbon approaches could save millions of dollars. The technology application described herein has the potential to reduce compliance cost by $200M for a 700 MW facility burning PRB coal.
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Type
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Book
|
|
Author
|
Mark
Simpson Berry
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|
URL
|
|
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Publisher
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The
University of Alabama at Birmingham
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Gas Desulfurization with Solid By-Products from Thermo-Chemical Conversion of Sewage Sludge
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Type
|
Journal
Article
|
|
Author
|
N.
Gil-Lalaguna
|
|
Author
|
J.L.
Sánchez
|
|
Author
|
M.B.
Murillo
|
|
Author
|
G.
Gea
|
|
URL
|
|
|
Date
|
2014
|
|
DOI
|
|
|
Accessed
|
4/25/2017,
3:07:19 PM
|
|
Library
Catalog
|
DataCite
|
|
Abstract
|
This
work aims to study the desulfurization ability of the solid by-products
obtained from both combustion and gasification of sewage sludge. Due to its
metal content (calcium and iron oxides among others), sewage sludge ash could
be a potential hot desulfurization sorbent. Desulfurization tests were
carried out in a lab-scale fixed bed reactor operating at 600-800 ºC and under
different gas atmospheres containing H2S. The reduced atmosphere created by
the gasification gas was detrimental for H2S removal. Thermal instability of
iron oxides in reducing atmospheres may be the main reason for this result.
The presence of steam in the gasification gas also affected negatively the
final sulfur content in the ash due to the simultaneous regeneration of the
spent metal sulfides. In general, sewage sludge combustion ash (rich in
Fe2O3) showed better desulfurization performance than sewage sludge
gasification ash (rich in Fe3O4).
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Improving the electrostatic precipitation removal efficiency by desulfurized wastewater evaporation
|
Type
|
Journal
Article
|
|
Author
|
Hu
Bin
|
|
Author
|
Yi
Yang
|
|
Author
|
Yang
Chunmin
|
|
Author
|
Zhang
Lin
|
|
Author
|
Yang
Linjun
|
|
URL
|
|
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Volume
|
6
|
|
Issue
|
114
|
|
Pages
|
113703-113711
|
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Publication
|
RSC
Advances
|
|
Date
|
2016/11/29
|
|
Abstract
|
A
novel technique was developed to improve the removal of fine particles by
electrostatic precipitation. The performance of a lab-scale ESP spraying
desulfurized wastewater was investigated under controlled conditions in a
coal-fired thermal system. The fine particles' properties, electric
performance, wet flue gas desulfurization efficiency and pH were analyzed.
Moreover, the factors that influence the removal efficiency of ESP, including
operating voltage, wastewater flow rate, and atomized droplets' diameter, were
also analyzed. It was found that the average diameter of particles increases
from 0.15 to 0.5 μm due to the evaporation of desulfurized wastewater, which
is confirmed by SEM. Fine particles removal efficiency by ESP was greatly
improved from 68% to 83%. Moreover, the ESP removal fine particle efficiency
could be affected by the wastewater flow rate, operating voltage, and
atomized droplet diameter. Finally, the influence of the WFGD system was
analyzed, indicating that the desulfurized wastewater evaporation had little
impact on the desulfurization system. This novel technique can improve the
removal efficiency of ESP with zero discharge by implementing the
desulfurization wastewater evaporation.
|
Institute for Combustion Science
Combustion Laboratory
The Combustion Laboratory, established in 1993, focuses on the behavior of chlorine, sulfur, and mercury during combustion. Since the construction of the 0.1MWth laboratory scale fluidized-bed combustor (FBC system) in 1995, over a half million dollars in research funding have been received from the U.S. Department of Energy, EPRI, the Illinois Clean Coal Institute, and the Tennessee Valley Authority. The FBC system has been involved in over 8000 hours of testing. This amount of testing time is the longest that has been conducted by any university FBC system in the United States.
The Combustion Laboratory was also awarded a two million dollar grant from the U.S. Department of Energy for their project on "Establishment of an Environmental Control Technology Laboratory with a Circulating Fluidized Bed Combustion System" in the year 2004. The primary objective of this project is to establish an Environmental Control Technology Laboratory (ECTL) using a multi-functional circulating fluidized bed combustion (CFBC) system. The system can be easily configured to make combustion runs with various fuels (such as coal, coal fine, biomass, solid wastes and RDF) under varying conditions to analyze and monitor air pollutant emissions, as requested by the lab’s industrial partners. The successful development of these technologies will provide scientific data on atmospheric pollutants resulting from combustion systems and the methodologies required to reduce the emission of these pollutants across the United States.
Since 2002, the Combustion Laboratory has been participating in an ongoing carbon dioxide (CO2) sequestration research project using an aqueous ammonia scrubbing technology with China and other countries. CO2 produced from combustion sources, such as fossil fuel-fired power plants, is captured from the flue gas. The CO2 reacts with aqueous ammonia to form ammonium bicarbonate (ABC), which can act as a “CO2 carrier” to “transport” CO2 from the combustion of fossil fuels to soil structure and crops in the farmlands due to its water solubility. ICSET scientists have investigated the fate of carbon distribution after the ABC fertilizer is applied to soil. It was found that a considerable amount (up to 10%) of the carbon source is absorbed by plants with increased biomass production. The majority of the unused carbon source (up to 76%) percolated into the aquifer to form stable carbonates. Of those 76% carbon, up to 88% was in the form of insoluble salts (i.e., CaCO3) in alkaline soils. Ammonia scrubbing in a slipstream reactor in real flue gas condition is under investigation at the Combustion Laboratory.
The Combustion Laboratory has investigated two approaches aimed at reducing the environmental impact and human health risk associated with animal confined feeding operations. They are (1) maximizing beneficial utilization of animal waste and (2) reducing ammonia emissions from animal feeding operations. Over the past year, ICSET at WKU developed processes for preparing activated carbon from chicken waste and coal for mercury capture. Low-cost activated carbon samples were prepared from a co-process of chicken wastes. Also, a continuous NH3 emission monitoring study of confined feeding operation (CFO) facilities was carried out using 4 commercially available NH3 monitoring systems. During a two-week monitoring period, it was found that the concentration of NH3 in the test poultry house showed an opposite trend to the ambient temperature. High ambient temperature affected the operation of the venting system, which brought air from outside of the test facility and resulted in the observed lowering in NH3 concentration due to dilution.
Kentucky is ranked second in the nation in installed flue gas desulfurization (FGD) scrubber capacity for coal-fired power plants. As a result, large amounts of FGD by-products are produced annually. An increase in the utilization of FGD by-products (e.g. agricultural land application) creates significant economic opportunities for the state of Kentucky. However, concerns about the release of hazardous elements have inhibited the usage. The Combustion Laboratory is evaluating the environmental impact associated with land application of the FGD by-product. In this project, the emission, leaching, and bioaccumulation of Mercury (Hg) and other environmentally-concerned trace elements (e.g. Arsenic (As), Selenium (Se), and Chromium (Cr)) from soil, which are amended using FGD by-products, will be quantitatively and mechanically determined. The benefit of using FGD by-products in improving plant growth and soil properties will also be systematically demonstrated.
A laboratory scale gasification unit has been constructed at the Combustion Laboratory. The gasification system has developed a number of important gasification programs, including Advanced Gasification Syngas Multi-Contaminant Cleanup Technologies and Novel Gasification Concepts (e.g. chemical looping gasification and co-gasifying coal with CBM to produce a synthesis gas with an adjustable H2/CO ratio). Additional benefits may include economical abatement of sulfur emissions and the production of a potential mercury sorbent. This process is based on some key chemical reaction mechanisms and their cooperative effects.
Other research projects, “Development for Clean Coal Technology-Horizontal Swirling Fluidized Bed Boiler,” and “Application of a Circulating Fluidized Bed Process for the Chemical Looping Combustion of Solid Fuels” are also conducted in this laboratory.
Current Research Projects:
One-step Bio-diesel Production by Synergetic Effect Using Cellulose Biomass and Bio-Oil
Emission Control in the Oxy-fuel Combustion Process
Production of Porous Materials from Waste Coals
Multiple-pollutants Control during Burning of Waste Coals and Solid Wastes in Circulating Fluidized Bed Process
Co-Gasification of High Sulfur Coal with Coal-bed Methane to Produce Synthesis Gas with Adjustable H2/CO Contents for Synthesis of Value Added Chemicals
Development of Clean Coal Technology: Horizontal Swirling Fluidized Bed Boiler
Study of Carbon Dioxide Removal from Flue Gas by Reaction with Aqueous Ammonia
Application of a Circulating Fluidized Bed Process for the Chemical Looping Combustion of Solid Fuels
Maximizing Co-Benefit from Multi-Utilization of Chicken Waste
The China Environmental Health Project
Instrumentation:
0.1MWth circulating fluidized bed combustion system
0.6MWth bench scale multi-functional circulation fluidized bed combustion (CFBC) system
2.5” ID multiple-purpose coal gasification unit (1100 0C)
Horizontal circulating fluidized bed cold and hot model
3” I.D. simulated fluidized bed combustor (up to 1100 0C)
2” I.D. tube flow reactor (up to 1100 0C)
1” Fixed Bed reactor (up to 1100 0C)
Simulated selective catalytically Reactor (SCR) system (0.1MW)
Simulated wet flue gas desulfurization system
1” Lab-scale supercritical higher pressure unit
Sulfur trioxide generator
Simulated flue gas generation system
Photoacoustic multi-gas monitor (NH3, CO2, N2O, SO2, HCl and H2O)
Combustion-gas Analyzers (O2, NO, NO2, CO, N2O, SO2, and H2O)
Gas Chromatography/Mass Spectrometry
Capabilities:
Study pyrolysis, combustion and gasification for different fuels, such as coal, biomass and solid wastes
Carbon dioxide reduction and sequestration
Conduct experiments of cracking reaction for different chemicals
Development and manufacture of lab-scale and pilot-scale reactor
Development and manufacture of cold-model of reactor
Investigate hydrodynamics heat and mass transfer in multiphase flow systems
Process integration on mercury emission control
Development and evaluation of adsorbents for combustion and gasification process
Erosion and corrosion of heat exchange tubes in combustion systems
Selected Publications:
Li, Songgeng; Wu, Andy; Deng, Shuang; Pan, Wei-Ping. “Effect of Co-combustion for Chicken Litter and Coal on Emissions in a Laboratory-scale Fluidized Bed Combustor,” Fuel Processing Technology, 2008 , 89, 7-12.
Cheng, Zhongxian; Ma, Youhua; Li, Xin; Zhang, Zhiming; Pan, Wei-Ping. “Investigation of Carbon Distribution with 14C as Tracer for Carbon Dioxide (CO2) Sequestration through NH4HC03 Production,” Energy & Fuels, 2007, 27, 3334-3340.
Cui, Hong; Cao, Yan; Pan, Wei-Ping. “Preparation of Activated Carbon for Mercury Capture from Chicken Waste and Coal,” J. Anal. Appl. Pyrolysis, 2007, 80(2), 319-324.
Lingchuan Li, Yufeng Duan, Yan Cao, Paul Chu, Ron Carty, and Wei-Ping Pan, “Field Corrosion Test for a Low Chromium Steel Carried out at Superheater Area of a Utility Boiler with Three Coals Containing Different Chlorine Contents,” Fuel Processing Technology, 2007, 88, 387-392.
Yan Cao and Wei-Ping Pan, “Investigation of Chemical Looping Combustion by Solid Fuels 1. Process Analysis,” Energy & Fuels, 2006, 20, 1836-1844.
Yan Cao, Bianca Casenas*,and Wei-Ping Pan, “Investigation of Chemical Looping Combustion by Solid Fuels 2. Redox Reaction Kinectics and Product Characterization with Coal, Biomass and Solid Waste as Solid Fuels and CuO as Oxygen Carrier,” Energy & Fuels, 2006, 20, 1845-1854.
Yan Cao, Yang Wang, John T. Riley, and Wei-Ping Pan, “A Novel Biomass Air Gasification Process for Producing Tar-free Higher Heating Value Fuel Gas,” Fuel Processing Technology, 2006, 87, 343-353.
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9ο ΠΕΣΧΜ: Η Συμβολή της Χημικής Μηχανικής στην Αειφόρο Ανάπτυξη
LIQUID-PHASE ADSORPTIVE DESULFURIZATION OF DIESEL FUEL (2013)
G. Karagiannakis, P. Baltzopoulou, I. Dolios and A.G. Konstandopoulos
Aerosol & Particle Technology Laboratory, CPERI/CERTH, P.O. Box 60361, 57001, Thessaloniki, Greece
A.G. Konstandopoulos
Department of Chemical Engineering, Aristotle University, P.O. Box 1517, 54006, Thessaloniki, Greece
ABSTRACT
The present work investigates the lab-scale liquid desulfurization (deS) of commercial diesel fuel via adsorption, under ambient conditions, employing a high-surface area activated carbon (AC) sorbent. The selected sorbent was able to desulfurize a commercial diesel fuel (total sulfur content: 7.1 ppmw) up to sub-ppm values. The breakthrough curves indicated that for a processed diesel fuel amount of up to about 20 ml⋅g-1 AC, the total sulfur content was maintained below or equal to 2 ppmw. Several strategies for the regeneration of the partially saturated sorbent were also investigated. The most promising one involved washing of the adsorption bed with an organic solvent and subsequent heating at 200oC under low vacuum. However, even in this case the initial performance of the material (i.e. in its fresh form) could not be fully restored. More specifically, the aforementioned value for the breakthrough content of 2 ppmw of total sulfur was decreased to approximately 11 ml⋅g-1 AC after four adsorption/regeneration cycles. Based on multi-cyclic experiments, the performance of the material remained stable for at least 7 cycles in total. After the 7th cycle, further degradation of sorbent’s performance was observed.
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Type
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Journal
Article
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Author
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G.
Karagiannakis
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Author
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P.
Baltzopoulou
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Author
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I.
Dolios
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Author
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A.
G. Konstandopoulos
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URL
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Low-temperature H 2 S removal for solid oxide fuel cell application with metal oxide adsorbents
Abstract
The desulfurization of biogas is essential for the successful operation of solid oxide fuel cells. H2S is one of the main components in biogas. In order to feed a solid oxide fuel cell, the contaminated gas has to be reduced to a certain degree. In this work, different parameters onto the desulfurization performance of commercially available desulfurization adsorbents were investigated. The experiments were carried out using a custom made lab-scale unit. Synthetic biogas was passed through the sorbent bed and the outlet H2S concentration was measured. Experimental runs in a fixed bed reactor were conducted to monitor H2S removal efficiency of a zinc oxide adsorbent, an adsorbent based on a mixture of manganese and copper oxide and a zeolite adsorbent. H2S removal efficiency was monitored under various operating conditions such as different temperatures, space velocities and inlet concentrations. This work provides useful data for adsorption tower design and process optimization.
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Type
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Journal
Article
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Author
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Christof
Weinlaender
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Author
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Raphael
Neubauer
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Author
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Christoph
Hochenauer
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URL
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Volume
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35
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Issue
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1-2
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Pages
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120-136
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Publication
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Adsorption
Science & Technology
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Date
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03/2017
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Microbiological analysis of the population of extremely haloalkaliphilic sulfur-oxidizing bacteria dominating in lab-scale sulfide-removing bioreactors
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Type
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Journal
Article
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Author
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D.
Y. Sorokin
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Author
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P.
L. F. van den Bosch
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Author
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B.
Abbas
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Author
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A.
J. H. Janssen
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Author
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G.
Muyzer
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URL
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Volume
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80
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Issue
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6
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Pages
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965-975
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Publication
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Applied
Microbiology and Biotechnology
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Abstract
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Thiopaq
biotechnology for partial sulfide oxidation to elemental sulfur is an
efficient way to remove H2S from biogases. However, its application for
high-pressure natural gas desulfurization needs upgrading. Particularly, an
increase in alkalinity of the scrubbing liquid is required. Therefore, the
feasibility of sulfide oxidation into elemental sulfur under oxygen
limitation was tested at extremely haloalkaline conditions in lab-scale
bioreactors using mix sediments from hypersaline soda lakes as inoculum. The
microbiological analysis, both culture dependent and independent, of the
successfully operating bioreactors revealed a domination of obligately
chemolithoautotrophic and extremely haloalkaliphilic sulfur-oxidizing
bacteria belonging to the genus Thioalkalivibrio. Two subgroups were
recognized among the isolates. The subgroup enriched from the reactors
operating at pH 10 clustered with Thioalkalivibrio
jannaschii–Thioalkalivibrio versutus core group of the genus
Thioalkalivibrio. Another subgroup, obtained mostly with sulfide as substrate
and at lower pH, belonged to the cluster of facultatively alkaliphilic
Thioalkalivibrio halophilus. Overall, the results clearly indicate a large
potential of the genus Thiolalkalivibrio to efficiently oxidize sulfide at
extremely haloalkaline conditions, which makes it suitable for application in
the natural gas desulfurization.
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Modeling, Simulation and Optimization of a Syngas Desulfurization Device
One of the critical areas of the IGCC technology is the sulfur removal from the syngas. Current processes are of the “cold” type: the syngas is cooled downstream of the gasifier, treated, and then reheated before combustion: this is scarcely an optimal procedure, and leads in fact to an important loss of global efficiency. A promising alternative is the HTHPD, a high-temperature/high-pressure desulfuration process based on a regenerable Zn/Ti sorbent. In the HTHPD the sulfur compounds are first adsorbed in a fluidized-bed reactor by sorbent pellets that are then transported to another reactor to be regenerated in an O2-rich stream: the sulfur is removed as SO2 or CaSO4. At present, the HTHPD technology is at pilot-scale demonstration stage, and the first results show a potential for improving the overall plant efficiency by about one percentage point. The Project ENEA/DMA foresaw the development of a physical-chemical model of a HTHPD device and its implementation in a simulation environment consisting of a modular process simulation software (CAMEL-Pro) that allows the user to solve and analyze plant configurations by using components and streams previously defined in the code’s libraries. In the work performed within the scope of the present project, we have modeled a hightemperature/ high-pressure desulfuration process (HTHPD) that employs a regenerable Zn/Ti based sorbent. The model is based on strongly simplified reaction kinetics, on a proper black-box schematization of the known phenomenological aspects of the problem, on published data about process schemes and on the few available experimental results. The desulfuration reactor model relates the reactor performance with the sorbent characteristics and the operating conditions: temperature, pressure, syngas mass flow, H2S concentration, etc., deriving real-scale reactor results from lab-scale experimental results. The performance curves obtained for the HTHPD do not make explicit use of reaction kinetics, but in a way “embed” it in an integral sense, in the same way a compressor operating map “embeds” the local thermo-fluiddynamics of the flow. As such, the general method described in this Report can be used to derive the performance maps of any chemical reactor, paving the way to a series of practical applications in the development of process simulators.
ENEA – Progetto CERSE
Dipartimento di Meccanica & Aeronautica – Gruppo
CIRCUS
TR ENEA/DMA/010509
Final Report
May 7, 2009
Enrico Sciubba
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Type
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Report
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Author
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Enrico
Sciubba
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URL
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Institution
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Report
RSE/2009/195
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Modeling studies of biological gas desulfurization under haloalkaline conditions
Biogas, synthesis and natural gas streams often require treatment because of the presence of gaseous hydrogen sulphide (H2S). About 25 years ago, a biotechnological gas treatment process was developed as an alternative to the conventionally applied technologies. This process is known as the Thiopaq process and offers a number of advantages compared to the existing physical-chemical processes. Depending on the process conditions, H2S is oxidized to elemental bio-sulfur (90-94 mol%) and sulphate (6-10 mol%). In order to enable cost effective large scale applications, the selectivity for sulfur production should be increased to more than 97 mol%. Hence, a better understanding of the combined effect of abiotic and biological reaction kinetics and the relation to hydrodynamic characteristics is required. The first part of this PhD study focuses on biological reaction kinetics and biological pathways for sulphide oxidation that occur in the process at haloalkaline conditions. It was found that two different sulfide oxidizing enzyme systems are present in haloalkaline sulfide oxidizing bacteria. It has been hypothesized that the different enzymatic routes are determined by the process conditions. Both enzyme systems were taken into account to propose and validate a new physiological mathematical model that can handle multi-substrates and multi-products. In the second part of the thesis, this model was evaluated via a normalized sensitivity method and it was demonstrated that certain key parameters affect the activity of the biomass at different substrate levels. Furthermore, from CSTR simulations it has been demonstrated that non-linear effects are of importance when scaling up from lab-scale to full-scale industrial units. Finally, the developed kinetic models have been incorporated in a full-scale biodesulfurization model that includes the effects of turbulent flow regimes and mass transfer of oxygen. This enables us to better understand the overall process. Moreover, the model can also be used as a tool to design model-based control strategies which will lead to better overall process performance, i.e. maximize sulfur production and minimize chemical consumption rates.
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Type
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Book
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Author
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J.B.M
Klok
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URL
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Place
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Wageningen
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Publisher
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Wageningen
University
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Date
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2015
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Operational aspects of the desulfurization process of energy gases mimics in biotrickling filters
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Type
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Journal
Article
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Author
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Marc
Fortuny
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Author
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Xavier
Gamisans
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Author
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Marc
A. Deshusses
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Author
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Javier
Lafuente
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Author
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Carles
Casas
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Author
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David
Gabriel
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URL
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Volume
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45
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Issue
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17
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Pages
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5665-5674
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Publication
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Water
Research
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Date
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Nov
01, 2011
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Abstract
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Biological
removal of reduced sulfur compounds in energy-rich gases is an increasingly
adopted alternative to conventional physicochemical processes, because of
economical and environmental benefits. A lab-scale biotrickling filter
reactor for the treatment of high-H(2)S-loaded gases was developed and
previously proven to effectively treat H(2)S concentrations up to 12,000
ppm(v) at gas contact times between 167 and 180 s. In the present work, a
detailed study on selected operational aspects affecting this system was
carried out with the objective to optimize performance. The start-up phase
was studied at an inlet H(2)S concentration of 1000 ppm(v) (loading of 28 g
H(2)S m(-3) h(-1)) and inoculation with sludge from a municipal wastewater
treatment plant. After reactor startup, the inlet H(2)S concentration was
doubled and the influence of different key process parameters was tested.
Results showed that there was a significant reduction of the removal
efficiency at gas contact times below 120 s. Also, mass transfer was found to
be the main factor limiting H(2)S elimination, whereas performance was not
influenced by the bacterial colonization of the packed column after the
initial startup. The effect of gas supply shutdowns for up to 5 days was
shown to be irrelevant on process performance if the trickling liquid
recirculation was kept on. Also, the trickling liquid velocity was
investigated and found to influence sulfate production through a better use
of the supplied dissolved oxygen. Finally, short-term pH changes revealed
that the system was quite insensitive to a pH drop, but was markedly affected
by a pH increase, affecting both the biological activity and the removal of
H(2)S. Altogether, the results presented and discussed herein provide new
insight and operational data on H(2)S removal from energy gases in
biotrickling filters.
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Optimization of adsorptive desulfurization process of jet fuels for application in fuel cell systems
Abstract
In order to remove the sulfur compounds in jet fuels to produce ultra-clean fuels e.g., for fuel cell applications in aircraft (auxiliary power units, APUs), an integrated desulfurization process was developed, which combines a fixed-bed adsorption with a membrane separation. The present study focuses on the optimizing the fixed-bed adsorption with an Al2O3-based adsorbent. A sulfur level of 10 ppmw is required by the fuel cell system. 1 g of the adsorbent is capable of processing 7.43 ml of a 50% (vol.) light fraction of Jet A-1 with 440 ppmw under optimum operating conditions. The maximum sulfur adsorption capacity is approximately 2.51 mg S/g of adsorbent. The sulfur-loaded adsorbent can be regenerated by air rather than by hydrogen-containing gasses at an elevated temperature of 500 °C. However, the regenerated adsorbent only maintains a stable cyclic capacity of 2.01 mg S/g-ads over 70 adsorption–desorption cycles. In addition, the adsorbent bed dimensions with regard to bed length, bed diameter and particle size were optimized to obtain the desired sulfur adsorption capacity without encountering a significant pressure drop across the adsorption column.
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Type
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Journal
Article
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Author
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Y.
Wang
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Author
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J.
Geder
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Author
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J.M.
Schubert
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Author
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R.
Dahl
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Author
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J.
Pasel
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Author
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R.
Peters
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URL
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Volume
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95
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Pages
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144-153
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Publication
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Fuel
Processing Technology
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Date
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3/2012
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Pervaporative desulfurization of gasoline – separation of thiophene/n-heptane mixture / Perwaporacyjne odsiarczanie benzyny – separacja mieszanin tiofen/n-heptan
Abstract
This paper presents the recent advances in pervaporative reduction of sulfur content in gasoline. Methods of preliminary selection of membrane active layer material are presented. Interactions between gasoline components (typical hydrocarbon and sulfur species) and membranes are showed. Influence of pervaporation process parameters i.e. feed temperature, downstream pressure and feed flow rate on the separation efficiency is discussed. Investigations of the influence of sulfur concentration in fluid catalytic cracking (FCC) gasoline on membrane performance have been conducted. A series of PV tests was carried out to investigate the separation properties of the commercial composite membrane with an active layer made of poly(dimethylsiloxane) and to determine the efficiency of organic sulphur compound (thiophene) removal from model thiophene/n-heptane mixture depending on its concentration.
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Type
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Journal
Article
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Author
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Katarzyna
Rychlewska
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Author
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Krystyna
Konieczny
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Author
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Michał
Bodzek
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URL
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Volume
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41
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Issue
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2
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Publication
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Archives
of Environmental Protection
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Date
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2015-01-1
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PhD THESIS PROPOSAL
Student’s Name and Surname: Ebrahim Tilahun Mohammed
PROGRAMME: Environmental Engineering
DESULFURIZATION OF BIOGAS USING A MEMBRANE BIO-SCRUBBER
INTRODUCTION:
Biogas is a renewable and sustainable energy source which is produced by anaerobic fermentation of organic matter. The nature of the raw materials and the operational conditions used during anaerobic digestion processes will determine the chemical composition of the biogas. The raw biogas consists mainly, 40-75% of CH4 and 15-60% CO2 and minor constituents such as H2S (Hagen et al., 2001, Krich et al., 2005). Due to its calorific value, biogas is a potential energy source and it can be used for many applications such as gas fuel for vehicles and heat and power generation, feedstock for chemical production, and natural gas replacement (Lau et al., 2011; Tippayawong, 2011).
H2S transfers into the gas phase as a minor component of the biogas and restricts the direct use of raw biogas as a fuel. In addition to its unpleasant odor, H2S gas is highly toxic (Syed, et al., 2006; Tang et al. 2009), accelerates the corrosion of utilities (combustors, compressors, engines, boilers, etc.) and reduces lifespan of pipe work and other installations. The concentration of H2S in biogas can range from 0.1 to 2% v/v (1000-20,000 ppmv) (Fortuny et al., 2011), whereas manufacturers of combined heat and power (CHP) production units recommend limiting values between 0.01 and 0.03% v/v (100-300 ppmv) to control corrosion problem in piping systems and equipment, rarely unexpected peaks are allowed (Ramous et al., 2014). Therefore, H2S concentration in the biogas has to be controlled in order to prevent the damage and fulfill the quality standards required according to the final usage of the biogas (Deublein et al., 2008).
There are several technologies available for biogas desulfurization; based on physical (Belmabkhout et al., 2009), chemical (Peiffer and Gade, 2007) or biological principles (Chung et al., 2007; Lin et al., 2013). Although the physical desulfurization technologies such as membrane separation, water scrubbing and activated carbon adsorption are quite effective, they are not economical because of periodical replacement/regeneration costs of the consumed media (Ryckebosch et al., 2011). Chemical processes have also high operating costs because of the consumption of significant amounts of chemicals such as caustic soda
and iron salts (Table 1). Besides they produce secondary chemical wastes that should be treated properly before disposal (Lin et al., 2013). Bio-desulfurization processes are more attractive than physical and chemical processes because they can be operated inexpensively and its eco-friendliness, energy-savings and low-operating costs (Sakuma et al., 2006; Dennis and John, 2000).
The most commonly used biological processes for H2S removal can be classified into two groups: Internal and external bio-desulfurization (Beil et al, 2010). External biodesulfurization processes may be further classified as single stage and two-stage combined systems.
Internal bio-desulfurization, which is accomplished inside the digester or the headspace, is the simplest and cheapest method that is commonly used in farm-type digesters (Beil et al., 2010). In this process, small amount of air is injected into the head space of the anaerobic reactor so that the sulfide-oxidizing bacteria (SOB) can use it to oxidize H2S (Botheju and Bakke, 2011). Because of its low cost and availability, air is commonly used as source of oxygen. Several studies have confirmed the effectiveness of microaeration in biogas desulfurization, a disadvantage of this process is that, it can result in the accidental formation of explosion risk due to oxygen-biogas mixtures. Moreover, it results in the dilution of biogas with nitrogen gas, which decreases the calorific value of the biogas. Biogas desulfurization efficiencies above 97% can be achieved by injecting air without any impact on the digestion performance (Díaz et al., 2010a). In contrast, Jenicek et al. (2010) stated that introduction of air for internal biodesulfurization may cause aerobic decomposition of substrates and as a result the methane production could decline.
In external single-stage bio-desulfurization processes, the H2S oxidation takes place outside the anaerobic digester. The raw biogas passes through a fixed bed reactor, filled with moist packing materials on which the sulfide oxidizing bacteria grow. As fixed bed reactor, typically biofilters (BF) and trickling filters (BTFs) are used (Burgess et al., 2001).
In both systems, the desulfurization takes place in one step in a single reactor. In this way, the investment cost reduces significantly. Difficulties in controlling the operational parameters and clogging of the packing material are the drawbacks of single-stage biodesulfurization process (Montebello et al., 2012; Rodríguez et al., 2014). However, the main problem is the dilution of the biogas with the inert N2 gas and excess O2 supplied to the system in the form of air. Therefore this process is not suitable if the biogas is to be used as vehicle fuel or for grid injection due to the remaining traces of especially O2 (Petersson and Wellinger, 2009). BTFs are more widely used in odor control (Kim et al., 2005).
Two stage bio-desulfurization systems are often called bio-scrubbers. In bio-scrubbers, the gas absorption and cleaning occur separately in a two-stage process: chemical H2S absorption with an alkaline solution followed by bio-oxidation in an aerobic bio-reactor (Gabriel et al., 2013). The major benefit of bio-scrubbers is their
ability to deal with high H2S concentrations and also severe fluctuation. By using these systems removal efficiencies as high as 99% can be achieved (Fernandez et al., 2013). When compared with the single stage biotrickling filters, in two stage bio-scrubbers air is injected to the second bio-reactor, not to the first scrubbing unit, therefore there is no risk of N2 and O2 accumulation in the biogas (Allegue and Hinge, 2014). On the contrary, these systems are complex and have high capital and operational costs; hence their application range is restricted to large-scale biogas plants (Papadias et al., 2012).
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Type
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Attachment
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URL
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Recent advances and applications of reductive desulfurization in organic synthesis
Introduction
While the reductive desulfurization of thiols, thioethers, and Scontaining heterocycles is performed on a multi-million ton scale in down-stream oil processing in the production of gasoline, kerosene and Diesel fuel using heterogeneous molybdenum, cobalt, tungsten, or nickel sulfide catalysts, the true potential of this reaction in the lab scale total synthesis of natural products, biologically active compounds, or new materials has not been exploited yet. In this report we want to give a summary about the opportunities offered by reductive desulfurization as a synthetic tool in organic synthesis and highlight its applications as carbon-synthons or for tuning the reactivity and selectivity of reactions. There have been comprehensive reviews about the desulfurization of thio compounds with Raney-nickel by van Tamelen1 and Hauptmann2 from 1962 and a book chapter by Gol’dfarb3 from 1986. This review article builds on these earlier review articles to describe the current state of this subject and complements review articles about reductive desulfonylation,4,5 which will not be covered in this report, as this article focuses on non-oxidized sulfur species, such as thiols, thioethers, and thiophenes. This review also will not discuss the metal-catalyzed C(sp2)-SR cleavage as it has found numerous applications for the removal of RS-substituents as a strategic transformation in heterocyclic chemistry and can be reliably accomplished by a variety of methods.6e10 We have structured the material according to the fields of application, using the following categories: 1) thiophenes and saturated S-heterocycles as carbon fragments, 2) assembly of organic frameworks using the linchpin strategy, 3) deoxygenation of carbonyl groups via thioketalization, 4) increasing the reactivity of reactions by tuning the electronic properties of reagents, 5) increasing the selectivity of reactions by conformational restriction, and 6) as functional handles in peptide chemistry (Scheme 1). Naturally, certain applications would fit into more than one category, sowe arbitrarily classified such application into a single category to avoid overlap. The first examples of desulfurization of thioethers (e.g., 1),11 Scontaining amino acids (e.g., 2e3),11,12 or biotin methyl ester (4)13e15 have been reported by Mozingo et al. from Merck & Co in the 1940’s establishing Raney-Ni as a reagent for reductive desulfurization. Soon the desulfurization of thioketals (e.g., 5)16 and thiophenes (e.g., 6)17,18 was realized by other groups (Scheme 2).
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Journal
Article
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Author
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Jana
Rentner
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Author
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Marko
Kljajic
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Author
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Lisa
Offner
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Author
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Rolf
Breinbauer
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Volume
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70
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Issue
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47
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Pages
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8983-9027
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Publication
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Tetrahedron
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Date
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11/2014
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Recent advances and applications of reductive desulfurization in organic synthesis.pdf
Removal of Sulfur Dioxide from Flue Gas Using the Sludge Sodium Humate
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Journal
Article
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Author
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Yu
Zhao
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Author
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Guoxin
Hu
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URL
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Volume
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2013
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Pages
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e573051
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Publication
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The
Scientific World Journal
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Date
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2013/12/25
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Abstract
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This
study shows the ability of sodium humate from alkaline treatment sludge on
removing sulfur dioxide (SO2) in the simulated flue gas. Experiments were
conducted to examine the effect of various operating parameters, like the inlet
SO2 concentration or temperature or O2, on the SO2 absorption efficiency and
desulfurization time in a lab-scale bubbling reactor. The sludge sodium
humate in the supernatant after alkaline sludge treatment shows great
performance in SO2 absorption, and such efficiency can be maintained above
98% with 100 mL of this absorption solution at 298 K (flue gas rate of
0.12 m3/h). The highest SO2 absorption by 1.63 g SHA-Na is 0.946 mmol in the
process, which is translated to 0.037 g SO2 g−1 SHA-Na. The experimental
results indicate that the inlet SO2 concentration slightly influences the SO2
absorption efficiency and significantly influences the desulfurization time.
The pH of the absorption solution should be above 3.5 in this process in
order to make an effective desulfurization. The products of this process were
characterized by Fourier transform infrared spectroscopy and X-ray
diffraction. It can be seen that the desulfurization products mainly contain
sludge humic acid sediment, which can be used as fertilizer components.
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New Developments in Biology, Biomedical & Chemical Engineering and Materials Science
Scaling-Up Liquid-Liquid Extraction Experiments with Deep Eutectic Solvents
Emad Ali, Sarwono Mulyono, Mohamed Hadj-Kali
Abstract—New generation of green solvents, known as Deep Eutectic Solvents, have emerged as potential alternatives to conventional solvents in many industrial applications. Among these applications, removing sulfuric compounds from fuel oil is receiving much interest because organic sulfides becoming a serious source of pollution. The separation of aromatic and aliphatic hydrocarbons having the same number of carbon atoms is also a challenging process especially at low aromatic concentration. Deep Eutectic Solvents were utilized for the separation of aromatics using liquid-liquid extraction method and both the distribution ratio and selectivity were higher than that for sulfolane which is the most used solvent in industry. Laboratory scale results demonstrated the benefits of DESs in this separation operation. In this work the use of a pilot plant scale centrifugal extraction multi-stage unit is studied for the separation of thiophene from a mixture of thiophene and heptane. The pilot plant is being used for the validation of previous laboratory scale results. This could constitute a very important step towards the implementation of this method in industrial scale.
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Journal
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Author
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Emad
Ali
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Author
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Sarwono
Mulyono
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Author
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Mohamed
Hadj-Kali
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URL
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Study on the Reaction Characteristics of Flue Gas Desulfurization by Magnesia
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Type
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Conference
Paper
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Author
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L.
Wang
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Author
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Y.
Ma
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Author
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G.
Yuan
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Author
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J.
Hao
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Pages
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1-3
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Date
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June
2009
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DOI
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IEEE
Xplore
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Conference
Name
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2009
3rd International Conference on Bioinformatics and Biomedical Engineering
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Abstract
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Desulfurization
technics has been popularly applied to reduce the harmfulness of sulfur
dioxide. The reaction characteristics of flue gas desulfurization by magnesia
were studied using a lab-scale bubbling apparatus. The effects of
concentration of the reagent, flux of the flue gas, concentration of sulfur
dioxide, temperature of the absorbent, and bubbling depth on the
desulfurization efficiency was investigated with the parameters close to the
practice. The experimental results indicate that the desulfurization
efficiency is greatly influenced by flue gas flux, sulfur dioxide
concentration and bubbling depth. The desulfurization reaction is controlled
by the mass transfer of sulfur dioxide from the gas to the reagent solution.
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Proceedings
Title
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2009
3rd International Conference on Bioinformatics and Biomedical Engineering
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Date
Added
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4/25/2017,
1:33:23 PM
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Modified
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4/25/2017,
1:33:23 PM
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Tags:
absorbent
air pollution control
Boilers
bubbles
bubbling depth
chemical exchanges
chemical technology
Flue gas desulfurization
flue gas desulphurisation
flue gases
flue gas flux
gas industry
Industrial control
Investments
lab-scale bubbling apparatus
magnesia
magnesium compounds
mass transfer
Mg(OH)2
Power generation
Rain
reaction characteristics
SO2
sulfur dioxide concentration
sulphur compounds
Temperature
Weight control
Attachments
IEEE Xplore Abstract Record
Sustainable wet flue gas desulfurization: from lab-scale batch reactor to pilot scrubber
absorbent
air pollution control
Boilers
bubbles
bubbling depth
chemical exchanges
chemical technology
Flue gas desulfurization
flue gas desulphurisation
flue gases
flue gas flux
gas industry
Industrial control
Investments
lab-scale bubbling apparatus
magnesia
magnesium compounds
mass transfer
Mg(OH)2
Power generation
Rain
reaction characteristics
SO2
sulfur dioxide concentration
sulphur compounds
Temperature
Weight control
Attachments
IEEE Xplore Abstract Record
Sustainable wet flue gas desulfurization: from lab-scale batch reactor to pilot scrubber
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Web
Page
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URL
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Accessed
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4/25/2017,
12:36:51 PM
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Abstract
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Sustainable
wet flue gas desulfurization: from lab-scale batch reactor to pilot scrubber
on ResearchGate, the professional network for scientists.
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The Degree of Desulphurization of a Limestone/Gypsum Wet FGD Spray Tower using Response Surface Methodology
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Type
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Journal
Article
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Author
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J.
Z. Zhao
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Author
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B.
S. Jin
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Author
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Z.
P. Zhong
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URL
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Volume
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30
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Issue
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4
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Pages
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517-522
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Publication
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Chemical
Engineering & Technology
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Date
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April
1, 2007
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Abstract
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The
degree of desulphurization was studied using response surface methodology
(RSM), which enables effect examinations of parameters with a moderate number
of experiments. All experiments were conducted in a lab-scale spray tower for
limestone/gypsum wet flue gas desulphurization (FGD). The model flue gas was
prepared from air and SO2 gas. The SO2 concentrations in the gas phase were
determined by a multi-method analyzer. The degree of desulphurization
correlated well with operating parameters, including pH, L/G, T, and v, with
a determination coefficient R–Sq of 0.964. Effect tests indicate that L/G has
the most significant influence on the degree of desulphurization. The
interactions of L/G with pH, and with v, both play important roles. The
result indicates that the evolutive response surface model is helpful to
describe the degree of desulphurization of the limestone/gypsum wet FGD spray
tower.
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The development of a novel, selective desulfurization process
THE DEVELOPMENT OF A NOVEL, SELECTIVE DESULFURIZATION PROCESS
PROEFSCHRIFT
ter verkrijging van
de graad van doctor aan de Universiteit Twente,
op gezag van de rector magnificus,
prof.dr. W.H.M. Zijm,
volgens besluit van het College voor Promoties
in het openbaar te verdedigen
op woensdag 13 september 2006 om 13.15 uur
door
Hendrik ter Maat
Geboren op 8 juni 1968
te Rijssen, Nederland
Summary
The removal of hydrogen sulfide from natural, industrial of bio gas is an operation that is frequently encountered in process industry. Driven by tight sulfur specifications and the everlasting need for cost reduction a considerable research effort is made in this field, sprouting numerous new developments in desulfurization technology. The procede desulfurization process is a regenerative process that is capable of removing H2S from a gas stream without the uptake of CO2. The removal of H2S is selective since the absorption process is based on the precipitation reaction of H2S with metal ions present in an aqueous solution under the formation of metal sulfide. The desulfurization of gas streams using aqueous iron(II)sulfate (Fe(II)SO4), zinc sulfate (ZnSO4) and copper sulfate (CuSO4) solutions as washing liquor is studied theoretically and experimentally (Chapter 2. A thermodynamic study has been used to determine a theoretical operating window, with respect to the pH of the scrubbing solution, in which the metal sulfate solution can react with hydrogen sulfide (H2S), but not with carbon dioxide (CO2) from the gas or hydroxide ions from the scrubbing solution. When the absorption is carried out in this window the proposed process should be capable of removing H2S from the gas stream without uptake of CO2 or the formation of metal hydroxides. The pH operating window increases in the order of iron, zinc to copper. Experimental verification showed that the proposed process indeed efficiently removes H2S when an aqueous Fe(II)SO4, ZnSO4 or CuSO4 solution is used as absorbent. However, for an efficient desulfurization the lower pH of the experimental pH operating window using the Fe(II)SO4 or ZnSO4 solution was higher than indicated by thermodynamics. The reason for this must probably be attributed to a reduced precipitation rate at decreasing pH. When a CuSO4 solution is used as washing liquor the solution can efficiently remove H2S over the entire pH range studied (as low as pH = 1.4). In this case only the upper pH boundary of the operating window (that indicates the possible formation of copper hydroxide or copper carbonates) seems to be a relevant limit in practice. The laboratory experiments indicate that the absorption of H2S in a CuSO4 solution, at the experimental conditions tested, is a gas phase mass transfer limited process. This allows a high degree of H2S removal in a relatively compact contactor. In addition to the lab scale experiments the potential of the new desulfurization process has also been successfully demonstrated for an industrial biogas using a pilot scale packed bed reactor operated with a fresh and regenerated CuSO4 solution. The desulfurization of gas streams using aqueous copper sulfate (CuSO4) solutions as washing liquor is subject of a more detailed investigation (Chapter 3). Absorption experiments of H2S in aqueous CuSO4 solutions were carried out in a Mechanically Agitated Gas Liquid Reactor. The experiments were conducted at a temperature of 293 K and CuSO4 concentrations between 0.01 and 0.1 M. These experiments showed that the process efficiently removes H2S. The experiments indicate that the absorption of H2S in a CuSO4 solution may typically be considered a mass transfer limited process at, for this type of industrial process, relevant conditions. The extended model developed by Al-Tarazi et al. has been used to predict the rate of H2S absorption. This model describes the absorption and accompanying precipitation process in terms of, among others, elementary reaction steps, particle nucleation and growth. The results from this extended model were compared to results obtained with a much simpler model, regarding the absorption of H2S in CuSO4 containing aqueous solutions as absorption of a gas accompanied by an instantaneous irreversible reaction. From this comparison it appeared that the absorption rate of H2S in a CuSO4 solution can, under certain conditions, be considered as a mass transfer rate controlled process. Under a much wider range of conditions the error that is made by assuming that the absorption process is a mass transfer controlled process, is still within engineering accuracy. This simplification allows for a considerable reduction of the theoretical effort needed for the design of a G/L contacting device, thereby still assuring that the desired gas specification can be met under a wide range of operating conditions. The oxidation of copper(II)sulfide to copper(II) oxide, required for the regeneration of copper sulfide is studied (Chapter 4). The possibilities for a selective and efficient method to convert copper(II)sulfide (CuS) into copper(II)oxide (CuO)of CuS are investigated. The reaction routes of the oxidation of copper sulfide as a function of reaction temperature and gas composition are established. The oxidation of copper sulfide is studied experimentally using a Thermo Gravimetric Analyzer (TGA) at temperatures ranging from 450ºC to 750 ºC and oxygen concentrations of 5 and 10 V%. It appeared that the products formed upon the oxidation of copper sulfide depend on the reaction temperature. However, in all cases the conversion time using the powdered samples was much shorter than expected based on literature results (typically 3 minutes versus 1-3 hours as mentioned in literature). The first reaction step in the oxidation of copper sulfide always was the fast decomposition of CuS into Cu2S and gaseous sulfur, which immediately is oxidized further to SO2. Subsequently, Cu2S is then oxidized, the route depending on the reaction conditions. Oxidation experiments carried out at various temperatures showed that Cu2S is oxidized selectively to CuO at temperatures above 650 ºC, while at temperatures below 650 ºC (basic) copper sulfate was also formed. The oxidation from Cu2S to CuO appeared to be the result of two consecutive reactions. Cu2S is first converted into Cu2O, which is subsequently oxidized to CuO. The experimental results allowed for the determination a rate expression and (Arrhenius) relation for the reaction rate constant of the conversion of Cu2S to Cu2O between 650 and 750 ºC and oxygen concentrations between 5 and 10 V%. The process design and economic potential of the procede desulfurization process were studied (Chapter 5). The high selectivity towards H2S of this process, along with the relatively high value of the obtained final products are key advantages. The economic performance of this process was studied using a Discounted Cash Flow analysis (DCF). The economic performance of the procede desulfurization process in comparison to its main, large scale, competitor: the amine based gas sweetening process was established. It was found that although both processes (logically) cost money when the product revenues were neglected, the economic performance of the novel process was substantially better than the economic performance of a conventional, amine based desulfurization unit. Owing to the relatively low operating costs, retrofitting an existing amine based desulfurization unit can be a very attractive option. It was also established that the competitive edge of the procede desulfurization process improved at higher CO2 or lower H2S concentrations in the feed gas, but decreases when copper losses during regeneration occur. Furthermore the economic advantage of the copper sulfate based process over the amine based process increased further when the product revenues were taken into account.
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Type
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Thesis
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Author
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H.
ter Maat
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URL
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Place
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S.l.
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Date
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2006
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Extra
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OCLC:
150249984
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Ultrasonically Assisted Oxidative Desulfurization (UAODS)
Ultrasonically Assisted Oxidative Desulfurization (UAODS) Sulfur-containing compounds in crude oil, petroleum, diesel and other fuel oils include sulfides, thiols, thiophenes, substituted benzo- and dibenzothiophenes (BTs and DBTs), benzonaphthothiophene (BNT), and many more complex molecules, in which the condensed thiophenes are the most common forms. Hielscher ultrasonic reactors assist the oxidative deep desulfurization process required to meet the today’s stringent environmental regulations and ultra-low sulfur diesel (ULSD, 10ppm sulfur) specifications. Oxidative Desulfurization (ODS) Oxidative desulfurization with hydrogen peroxide and subsequent solvent extraction is a two-stage deep desulfurization technology to reduce the amount of organosulfur compounds in fuel oils. Hielscher ultrasonic reactors are used at both stages to improve phase-transfer reaction kinetics and dissolving rates in liquid-liquid phase systems.
At the first stage of ultrasonically assisted oxidative desulfurization, hydrogen peroxide is used as an oxidant to selectively oxidize the sulfur-containing molecules that are present in fuel oils to their corresponding sulfoxides or sulfones under mild conditions to increase their solubility in polar solvents with an increase in their polarity. At this stage, the insolubility of the polar aqueous phase and the nonpolar organic phase is a significant problem in the process of oxidative desulfurization as both phases react with each other only at the interphase. Without ultrasonics, this results in a low reaction rate and a slow conversion of organosulfur in this two-phase system.
Ultrasonic Emulsification The oil phase and the aqueous phase are mixed are pumped into a static mixer to produce a basic emulsion of a constant volumetric ratio that is then fed to the ultrasonic mixing reactor. In there, ultrasonic cavitation produces high hydraulic shear and breaks the aqueous phase into sub-micron and nanosize droplets. As the specific surface area of the phase boundary is influential for the chemical rate of reaction this significant reduction in droplet diameter improves the reaction kinetics and reduces or eliminates the need for phase-transfer agents. Using ultrasonics, the volume percentage of the peroxide can be lowered, because finer emulsions need less volume to provide the same contact surface with the oil phase.
Ultrasonically Assisted Oxidation Ultrasonic cavitation produces intense local heating (~5000K), high pressures (~1000atm), enormous heating and cooling rates (>109 K/sec), and liquid jet streams (~1000 km/h). This extremely reactive environment oxidizes thiophenes in the oil phase faster and more completely to greater polar sulfoxide and sulfones. Catalyst can further support the oxidation process but they are not essential. Amphiphilic emulsion catalysts or phase-transfer catalysts (PTC), such as quaternary ammonium salts with their unique capability to dissolve in both aqueous and organic liquids have been shown to incorporate with the oxidant and transport it from the interface phase to the reaction phase, thereby enhancing the reaction rate. Fenton’s reagent can be added to enhance the oxidative desulfurization efficiency for diesel fuels and it shows a good synergetic effect with the sono-oxidation processing.
Enhanced Mass-Transfer When the organosulfur compounds react at a phase boundary, the sulfoxides and sulfones accumulate at the aqueous droplet surface and block other sulfur compounds from interacting at aqueous phase. The hydraulic shear caused by cavitational jet streams and acoustical streaming result in turbulent flow and material transport from and to droplet surfaces and leads to the repeated coalescence and subsequent formation of new droplets. As the oxidation progresses over time, sonication maximizes the exposure and interaction of the reagents. Phase Transfer Extraction of Sulfones After the oxidation and the separation from the aqueous phase (H2O2), the sulfones can be extracted using a polar solvent, such as acetonitrile at the second stage. The sulfones will transfer at the phase boundary between both phases to the solvent phase for their higher polarity. Much like at the first stage, Hielscher ultrasonic reactors boost the liquid-liquid extraction by making a fine-size turbulent emulsion of the solvent phase in the oil phase. This increases the phase contact surface and results extraction and reduced solvent usage.
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TIP: Save time … Combine the two terms, bench scale and lab scale into a single search statement …
desulfurization AND (bench OR “lab scale”) ]
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