CHARACTERISTICS OF NATURAL GAS LIQUEFIERS FOR AUTOMOBILES FILLING STATIONS OF A NEW TYPE

Abstract

In the near future it is expected increasing a demand for liquefied natural gas (LNG) as the universal gas fuel for motor transport and agricultural machinery.  Its efficient production can be organized on the basis of an automobile gas filling compressor station (AGFCS). To do this a station should be reconstructed to include in its composition of a natural gas liquefier (NGL). In NGL some equipment can use of the station as own operating time ratio is sometimes less than 40 %. However, the automobile filling stations can be created and based on independent NGS. At these stations, motor vehicles will be refueled or compressed NG (CNG) or LNG at presence of cryogenic fuel tanks. Several technological schemes of NGL with the work of their cycles by medium or high pressure have been considered. The analysis of the characteristics of NGL of medium pressure showed that for NGL regasification of obtained LNG for refueling of a natural gas of the motor cars specific costs in NGL will be 1,3 kWh/kg. NGL efficiency can be greatly improved with the organization of its work on a cycle of high pressure. In it the work of the turbo expander is used in a compressor stage of the unit for compressing the entire return flow of gas liquefier to the pressure of its absorption of 1,0 MPa in the high-pressure compressor. The specific costs in NGL of a high pressure can be reduced by two times, that is to 0,65 kWh/kg.The advantage of such NGL is the absence in their schemes of refrigerating machines.