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Parreira Almond Processing Company N-1082706, N-1337-1-e,2-7,6-1. 7-0, 8-0 outer door is fully dosed is the inner door opened, allowing the feedstock to fall into the gasifier reaction area. The only openings in the gasifier, besides the double feestodk doors, are a similar set of double doors for ash removal, the combustion air ports, and the syngas exhaust port. Since a high-pressure blower located downstream of the syngas exhaust port is applying negative pressure on the gasifier(causing the pressure inside the gasifier vessel to be lower than the pressure outside the vessel by 2-8 Inches of water column), it is apparent that any potential emissions will be routed through the syngas exhaust port and there will be no emissions through the other doors or ports. Within the gasifier,four distinct processes take place as feedstock passes through the system. Since the gasifier is arranged vertically and the feedstock is added at the top, with ash and syngas removed at the bottom, it is apparent that these processes are gravity fed and occur in order as feedstock descends through the gasifier vessel. The first process is drying, in which moisture in the feedstock is driven off by the heat from processes occurring lower down in the gasifier vessel. The second process Is pyrolysis, in which organic material is heated with much less oxygen than is required for combustion. This reaction produces some of the synthetic gas as hydrogen and methane are released from the feedstock. The heat for the pyrolysis reaction comes from the third process, which is combustion. In the combustion zone, small air ports allow some outside air to enter the gasper and provide oxygen for combustion of the feedstock, but not enough air for full combustion. As the feedstock descends further in the gasifier vessel, it enters the reduction zone, in which final decomposition of solid material takes place. At the bottom of the gasifier, a grate supports the solid feedstock while allowing gases and ash to pass through. Gases are drawn by the high-pressure blower into the scrubbing filters,while ash Is removed by a screw conveyor equipped with double doors similar to the feedstock doors for disposal. When starting up the gasifier,feedstock is added to the combustion zone and Ignited using a hand-held propane torch.After ignition, the reaction is self-sustaining as long as sufficlent fuel and air are available. Therefore, no permanent natural gas or LPG burner is used to start up or sustain the gasifier. The principal advantage of this downdraft arrangement is that tars, which are complex organic molecules that haven't been fully broken down and which are normally a substantial problem when burning biomass, are drawn through all reaction zones to be broken down or burned. This results in approximately 99% reduction in tars In the syngas in comparison with updraft or fluid-bed gasification units'. Since the tars are the principal potentially hazardous emission, and the principal potential source of VOC emissions, such a reduction in tar, even before the filtering system, is extremely useful in reducing emissions and health risks. After the syngas is removed from the gasifier, it passes through a venturi scrubber, and then a series of filters, for removal of particulate matter.Water from the scrubber is cooled in a _ding tower at a rate of less than 10,000 gallons per minute,which mattes the cooling tower -- --— - exempt from permits pursuant to District Rule 2020, Section 6.2. The filer media is sawdust and wood chips, allowing the filter media to be used as feedstock when it is no longer useful as filter media. 'Application supplementary material, Section 3, Process and Equipment Description. 3