Syngas cleanup is a major challenge in any coal or biomass gasification application. A modified syngas cleanup process is under development to improve syngas from low rank coals for CTL (coal to liquids) applications. Novel steam reforming catalysts were developed to convert tars and light hydrocarbons and decompose ammonia in the presence of syngas contaminants such as H 2 S (< 500 ppm). Process goals are to improve syngas yield and H 2 :CO ratio while reducing water gas shift and downstream gas cleanup requirements. Laboratory reforming experiments were focused on developing information to support a techno-economic analysis using TRIG (transport reactor integrated gasifiers) or LURGI gasifiers. A CTL with carbon capture model was developed to compare the economics of the new process including the catalytic steam reforming to DOE (Department of Energy) baseline CTL. Reforming catalysts were developed that had high methane, tar, and ammonia conversion in presence of 90 ppm H 2 S. Higher concentrations of H 2 S affected conversion of methane but catalyst performance was fairly stable for the duration of testing. Results of modeling indicated that economics of the new process were nearly identical to the baseline CTL case, but greenhouse gas emissions for a given production of fuels were approximately 50% lower.

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The goal of this research program was to develop and demonstrate a novel gasification technology to produce substitute natural gas (SNG) from coal. The technology relies on a continuous sequential processing method that differs substantially from the historic methanation or hydro-gasification processing technologies. The thermo-chemistry relies on all the same reactions, but the processing sequences are different. The proposed concept is appropriate for western sub-bituminous coals, which tend to be composed of about half fixed carbon and about half volatile matter (dry ash-free basis.) In the most general terms the process requires four steps 1) separating the fixed carbon from the volatile matter (pyrolysis) 2) converting the volatile fraction into syngas (reforming) 3) reacting the syngas with heated carbon to make methane-rich fuel gas (methanation and hydro-gasification) and 4) generating process heat by combusting residual char (combustion). A key feature of this technology is that no oxygen plant is needed for char combustion iv

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Coal-cleaning processes have been utilized to increase the heating value of coal by extracting ash-forming minerals in the coal. These processes involve the crushing or grinding of raw coal followed by physical separation processes, taking advantage of the density difference between carbonaceous particles and mineral particles. In addition to the desired increase in the heating value of coal, a significant reduction of the sulfur content of the coal fed to a combustion unit is effected by the removal of pyrite and other sulfides found in the mineral matter.WRI is assisting PulseWave to develop an alternate, more efficient method of liberating and separating the undesirable mineral matter from the carbonaceous matter in coal. The approach is based on PulseWave's patented resonance disintegration technology that reduces that particle size of materials by application of destructive resonance, shock waves, and vortex generating forces.Illinois #5 coal, a Wyodak coal, and a Pittsburgh #8 coal were processed using the resonance disintegration apparatus then subjected to conventional density separations. Initial microscopic results indicate that up to 90% of the pyrite could be liberated from the coal in the machine, but limitations in the density separations reduced overall effectiveness of contaminant removal. Approximately 30-80% of the pyritic sulfur and 30-50% of the mercury was removed from the coal. The three coals (both with and without the pyritic phase separated out) were tested in WRI's 250,000 Btu/hr Combustion Test Facility, designed to replicate a coal-fired utility boiler. The flue gases were characterized for elemental, particle bound, and total mercury in addition to sulfur. The results indicated that pre-combustion cleaning could reduce a large fraction of the mercury emissions.iv