Abstract Booklet 2006 - Swanson School of Engineering - University ...

The Aim of the project is the improvement of the collaboration in the gas production
and utilization (from various kinds of fuels, incl. biomass and their mixtures).
Collaboration between both universities (VŠB-TU Ostrava a SIU Carbondale) was
started at 1993 and there is interest on various themes. Presently is interest on the
“clean gas” production, the special aspect of this work is environmental improvement
(minimizing of negative people impact to the antroposphere). On the SIU (Southern
Illinois University) Carbondale ware gasification engine – pilot with various output –
which can be use for the experiments. Collaboration intensification in the sphere
“clean gas” production and utilization of the results in the praxis and teaching process
Special interest of the research is given to the estimation of main conditions for the gas
production.
22-1
SESSION 22
ENVIRONMENTAL CONTROL TECHNOLOGIES:
SO x , NO x , PARTICULATE AND MERCURY – 2
Effectiveness of Clean Coal Technology Provisions of EPAct in
Addressing Current Environmental Issues Facing Coal
Ben Yamagata, Coal Utilization Research Council, USA
The Energy Policy Act of 2005 (EPAct) includes the enactment of numerous programs
designed to encourage the research, development, demonstration and deployment of clean
coal technologies. Except for the enactment of certain tax incentives designed to benefit
taxpayers utilizing qualifying clean coal technologies all other clean coal programs included
in last year s national energy legislation are authorizations that require appropriations in
order to become effective. The paper will review the various clean coal technology programs
that are included in EPAct and comment upon the rationale and justification cited by
Congress and industry for enactment of these provisions. With respect to industry s, and
particularly CURC s, rationale for these various programs, a Clean Coal Technology
Roadmap, first developed by EPRI and CURC, in consultation with the Department of
Energy, was a guiding document to define what objectives EPAct programs should be
designed to achieve. The Roadmap will be described as well as a discussion as to how the
EPAct programs might support achievement of the goals and objectives set forth in the
Roadmap. In order to succeed in achieving the goals of EPAct related to clean coal
technologies and to successfully reach the objectives defined in the Roadmap it will be
necessary to fully support the clean coal authorizations of EPAct. That is not happening.
Why and what are the potential consequences of a lack of attention to technology
development especially in light of possible regulation of carbon dioxide The paper will seek
to answer these questions and particularly will focus on the need for successful technology
development if policy makers choose to create a national or international carbon
management regulatory scheme.
22-2
A Novel Ammonia-Based FGD Process: Experiences of a 60MW Demonstration
Wen-De Xiao, East China University of Science and Technology, P.R. CHINA
More than 70% of the energy requirements are met by coal combustion in China, resulting in
severe environmental pollution by huge flue SO 2 discharge over 25 million tones a year. The
well-established and effective procedures to scope with SO 2 and acid rain troubles are flue
gas desulfurization (FGD). But the well-accepted and widely-applied limestone-based FGD
methods have been increasingly blamed where considerable second-hand pollutions
produced. The author and coworkers have been for a decade carried out research for a novel
FGD method, based on ammonia and co-producing a useful fertilizer, ammonium sulfate, as
displayed by: 2NH 3 +SO 2 +H 2 O+0.5O 2 =(NH 4 ) 2 SO 4 It is especially suitable for the Chinese
situations of huge ammonia and fertilizer industry. Furthermore, ammonia-based method is,
but limestone-based one is not, accordant to the green chemical principles.
This paper presents the operation experiences with a 60MW demo of the newly-developed
ammonia-based FGD process, shown in Figure 1, characterized by a multiple functional
column for SO 2 absorption to ammonium sulfite, sulfite oxidation to sulfate, and sulfate
crystallization. It also overcame shortage of the NH 3 slip in the outlet purified gas commonly
appeared in the conventional ammonia-based FGD methods by using two stages in between
NH 3 introduced.
Figure 2 depicts the operational results during a period of 168 hours for the evaluation of the
method when the inlet flue gas SO 2 content fluctuated between 200 and 1200 ppmv as the
result of shifting combusted coal from different mines. The FGD column is very robust for
the SO 2 content variation. The ammonium sulfate resulted met the top-grade fertilizer
specifications.
22-3
Oxy-Firing Flue-Gas Character and Its Effect on FGD -
A Process Study for Integrated Pollutant Removal
Danylo Oryshchyn, Jake Armstrong, Steve Gerdemann, Thomas Ochs, Cathy
Summers, NETL-Albany, USA
The National Energy Technology Laboratory (NETL) is investigating combining oxyfiring
coal, using recirculated flue gas enriched with oxygen, with a unique Integrated
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Pollutant Removal (IPR) system. Oxy-firing coal produces an exhaust stream
composition dominated by CO 2 and water, with particulate matter and small
contributions of SO x , NO x , O 2 , N 2 , Ar, and Hg. This is followed by the IPR system
which uses compression and intercooling to produce a supercritical, transportationready
CO 2 fluid suitable for sequestration or for purification, as necessary, to obtain
CO 2 for industrial use. Recent theoretical and experimental work at NETL is
examining three aspects of IPR: acid gas and particulate removal with energy recovery;
water treatment for recycle and release; and the enhancement of Hg 0 capture through
oxidation. Because their combination is corrosive, water, associated acid gases and
particulate matter must be removed from the boiler flue gas in the initial stages of IPR
to enable compression of the remaining CO 2 fluid. This study compared air-fired
furnace exhaust and oxy-fired furnace exhaust in flue gas desulfurization experiments.
Tests indicate the largest effect is associated with the greater concentration of SO 2 in
oxy-fired exhaust, despite the high concentration of CO 2 in this flue-gas composition.
22-4
Photocatalytic Decomposition of NO Originated from Coal Analog Compound
Xue Hanling, Li Jianwei, Ge Lingmei, Zhous Anning, Xi’an University of Science &
Technology, P.R. CHINA
Nitric oxide (NO) is the major air pollutant that has to be removed before emitting flue
gas into the atmosphere. Various processes, such as the selective catalytic reduction
(SCR) and selective non-catalytic reduction (SNCR), are under operation to remove
NO from flue gas. However, these processes require high operating temperatures and
costs. Recently, a great deal of research work has been carried out on the
heterogeneous photocatalytic reactions due to lower energy consumption and operating
cost for treatment of polluted water and air. This photocatalytic process has the
advantage of complete breakdown of organic pollutants to yield CO 2 , H 2 O and the
mineral acid. And studies on photocatalytic decomposition of NO have been reported.
It has been found that Cu + /zeolite catalysts exhibit photocatalytic reactivities for the
decomposition of NO x into N 2 and O 2 at 275K. In addition, a mixture of TiO 2 and
activated carbon is found to be an appropriate photocatalyst for the removal of lowconcentration
NO x from air. In the study, the photocatalytic oxidation of nitric oxide,
which was the oxidation product stemed from the mold compound pyridine of azocycle
compound in coal structure, over mesoporous loaded nanometer photocatalyst
containing metal compounds (MCs) has been studied in a fluidized-bed photoreactor.
Stannic oxide (SnO 2 ), zinc oxide (ZnO), cadmium sulfide (CdS), were used as MCs.
Mesoporous molecule sieve MCM-41 was acted as carrier, and TiO 2 was the primary
photocatalyst. The TiO 2 treated with MC over support MCM-41 by sol-gel method and
dipping process, had the greater efficiency as a NO remover under UV irradiation
compared with monocomponent TiO 2 . It is believed that MCM-41 has a high
adsorptivity for nitric oxide (NO) to contribute to photocatalytic reaction. The amount
of NO removed by the loaded photocatalyst including MC showed a tendency to
increase with decreasing initial NO concentration. The reaction rate increased with
reducing UV light wavelength. The NO decomposition activity depended on the
amount of semiconductor photocatalysts deposited in channel of MCM-41, too, and the
TiO 2 loaded with only 10wt%, meanwhile CdS loaded with only 5%, the photocatalyst
had revealed the highest level of activity in the fluidized-bed photoreactor, NO
decomposition reached about 64% at the gas velocity of 200ml/min. Highly dispersed
semiconductor photocatalysts in channel of MCM-41 was effective for the
photocatalytic decomposition of NO.
23-1
SESSION 23
HYDROGEN FROM COAL: SHIFT CATALYST AND GASIFICATION
Robust, Low-Cost Water-Gas Shift Membrane Reactor for
High-Purity Hydrogen Production from Coal-Derived Syngas
Zhijiang Li, Neng Ye, James Torkelson, Aspen Products Group, Inc., USA
In an effort to develop a reliable, low-cost membrane water-gas-shift reactor (WGS)
for hydrogen generation from coal-derived syngas, a sulfur-tolerant transition metal
WGS catalyst and a low-cost, H 2 -selective membrane were developed. Tests conducted
with synthetic syngas containing 3000 ppm sulfur showed that the WGS catalyst is
highly active and capable of converting CO at equilibrium conversions at temperatures
from 300 to 500ºC and pressures from 300 to 500 psig. The catalyst displayed higher
WGS activity than a number of commercial catalysts, especially at lower temperatures.
The stability of the catalyst in the presence of 3000 ppm H 2 S and 350 ppm HCl was
demonstrated for >200 hours. The H 2 -selective, high-temperature membrane is based
on a low-cost, hydrogen-selective material. The surfaces of the membrane were
modified by deposition of catalyst layers of desired compositions. H 2 permeation tests
conducted at 300-500ºC and up to 200 psi H 2 partial pressure showed that the
membrane is highly selective to H 2 with a H 2 permeability in the range of 1×10 -8 to
1×10 -7 mol H 2 /(m·s·Pa 0.5 ), comparable to that of Pd-based membranes. Surface
modification increases not only the membrane’s H 2 permeability but also its tolerance
to H 2 S.