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Parreire Almond Processing Company N-1082706,N-1337-1-6,2-7,6-1, 7-0,8-0 As can be seen in the syngas analysis in Appendix C, the syngas produced by this type of gasifier and feedstock contains approximately 19% hydrogen gas and 3% methane as the primary components.Although the combustion of pure hydrogen produces higher flame temperatures, and therefore more thermal NOx, than combustion of natural gas, the components of this sort of syngas are overwhelmingly non-combustible.These non-combustible components act as a quench gas, producing lower temperatures and NOx emissions.According to Figure 13 in the paper Research and Development of a low-BTU Gas- DHven Engine thr Waste Gasiffcat7on and Power Generation(Tokyo Institute of Technology, included as Appendix H), NO.emissions from the combustion of this sort of synthetic gas were below 1 g/kW hr in comparison with NOx emissions in excess of 15 g/kW hr from combustion of methane in the some engine. This means that, for a given engine, using this sort of syngas as the fuel can be expected to result in NOx emissions no greater than 10%of the NO,, emissions when using natural gas as the fuel. The proposed electrical generating system uses a rich-bum IC engine equipped with an air-to- fuel irto- fuel ratio (AFR) controller and a three-way catalyst. The AFR controller utilizes an oxygen sensor in the exhaust stack to measure the exhaust concentration.The oxygen sensor reports to a processing unit that employs proportionaWntegrai-derivative (PID)control logic to regulate an output signal, in this case to a valve regulating fuel flow to the engine, in a way that is both proportional to the existing error(the difference between the reading and the set point)and that reflects the rate at which that error is changing, allowing the output signal (and influent fuel flow) to "get ahead"of an input signal (and effluent 02 concentration)that is accelerating in an out-of-control direction. The combination of sensor, processor, and output signal allow the influent fuel flow to be regulated in such a way that the exhaust oxygen concentration is maintained at a rich-bum set point.This set point is precisely calibrated to allow optimum operation of the three-way catalyst, which is the other part of the emissions control system. The three-way catalyst functions by simultaneously catalyzing a reducing environment for NO, and an oxidizing environment for CO and VOC. In-general, a three-way catalyst reduces NOx emissions via the following series of chemical reactions(2): NOx+ CO -+ N2 + CO2 NO,+ CH4 N2 + CO2 + H2O NO,+ H2 N2 + H2O When combusting natural gas In the Caterpillar model G 3516 TA HCR engine, the catalyst manufacturer guarantees emissions at 5 ppmvd for NOx, 56 ppmvd for CO, and 25 ppmvd for VOC, all referenced at 15% 02. However, as previously mentioned, N%emissions resulting from syngas combustion will be lower than NOx emissions from natural gas combustion,and there is no data available from which to predict what impact the lower NO.concentration entering the catalyst will have on the overall control efficiency and resulting effluent NO, concentration. Yolo-Solano Air Quality Management District(YSAQMD) is currently working on an application for a similar electrical generating system using a gasifier and a rich-bum ergine with an AFR and three-way catalyst, and test data was submitted by that applicant in support x S E Southern California Gas Company,October 2002, page 1. 6