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• <br />Product Stream Service for Emission <br />Calculations Percent VOC in Stream <br /> <br />Product Gas <br />Gas _ <br />33% <br /> <br />Na htha <br />Light Oil _ <br />100% <br /> <br />Gas Oil <br />Heavy Oil _ <br />100% <br /> <br />Sour Water <br />Water/Oil _ <br />6% <br />For product gas, the emissions factor was adjusted to account for the VOC level <br />in the stream (33%), as the EPA emission factor represents to total gas loss through <br />fiigitive leaks. Non-VOCs in the product gas include methane, ethane, carbon dioxide:, <br />hydrogen sulfide, and ammonia. However, for sour water, the EPA eni nissions factor <br />already accounts for some fraction of water in the liquid stream so further adjustments for <br />VOC concentration of the stream were unnecessary. <br />The component count (valves, flanges, others) was estimated for each servic,:? <br />from project design data plus an additional multiplier of 1.25. Also, these emissions do <br />not include any reduction for an active leak detection and repair (LDAR) program. <br />Based on the calculations, the only reportable non-criteria air pollutant is hydrogen <br />sulfide (H,-,S), which exists primarily in the product gas stream. <br />Storage Tank Emissions <br />Storage tank emissions were estimated for the gas oil, naphtha, and slop oil fixed <br />roof tanks. The sour water tank will be vented to the thermal oxidizer, so these emissions <br />were not calculated separately. <br />The EPA TANKS Program (Tanks 4.0.9d) was used for the emission calculations. <br />Since AMSO's retort products are not listed in the TANKS database, a surrogate product <br />was chosen for the calculations based on having similar vapor pressures to the retort <br />products. For the gas oil product, the calculations used #6 oil as the surrogate, while the <br />naphtha product used gasoline (RVP 13.5) as the surrogate. Slop oil, which is a mixtur+-. <br />of naphtha and gas oil, was assumed to be naphtha (RVP 13.5 gasoline) as worst-case. <br />Because the vapor pressures of the surrogate are similar to the product of interest, this <br />procedure should reproduce the storage tank emissions for each retort product within a <br />reasonable accuracy. <br />The calculations for tank emissions will result in some "double counting" of <br />emissions. For throughputs, the calculations assuine all of the naphtha and all of the gas <br />oil will be routed to the storage tank. Also, it is assumed that up to 20% of these product; <br />will go through the slop oil tank. In fact, any product routed through the slop oil tank will • <br />Page 22 of 46