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Wildwood LNG Demonstration Facility 5.3 Liquefaction System The liquefaction system is the heart of the CFS technology. The proprietary cryogenic methodology that will be used for separating the nitrogen from the methane is still under development and will be tested in the proposed plant. Table 4 presents the design information used for the development of this system. The liquefaction system consists of a series of heat exchangers and separation vessels within a vacuum cold box. The purpose of the liquefaction system is to liquefy the (gaseous) natural gas to liquid natural gas through several steps of cooling and separation. This is strictly a physical process, and no chemicals or reactants are used. The two streams from the liquefaction process are the product LNG and vent gas produced during the separation steps. The vent gas generated during the separation process consists of approximately 45% nitrogen and 55% methane. The flow rate is approximately 100 scfin. The vent gas is used to regenerate the adsorbate beds in the TSA system. After regenerating the TSA beds, the gas is consumed as fuel in the engine-generator set. A closed loop refrigeration system provides the primarycooling,during the liquefaction process. After the natural gas is cooled to a liquid, it is further purified using separation vessels. After separation,the LNG product is transferred to the LNG storage tank by the system pressure. LNG product is produced at a rate of approximately four gallons per minute (gpm) at 20 psig. The proprietary elements of the CFS liquefaction system reduce the overall energy requirements by recovering a majority of the heat from the process and refrigeration streams. The streams are routed through a series of heat exchangers to either pre-cool or pre-heat the streams. This heat recovery system increases the operating efficiency and reduces the energy requirements of the system. The products from this system are the LNG product stream and the vent gas, which is used to regenerate the TSA beds and as a fuel supply for the engine-generator set. Vent gas is produced at a rate of about 100 scfm. No waste streams are produced from this system. In the event of an emergency, pressure relief valves designed to protect the vessels and piping from over pressurization may vent small quantities of natural gas into the atmosphere. Table 4 Design Information for the Liquefaction System Equipment,' Equipment Marne Pressure.(PSIG). Temperature (°F) Flow Rate Number Operatrng/Design Operating/Designscfm 40-3202 Process Gas Feed 350/400 20/100 i 600 Cooler AES Construction Group Page 7