COMPRESSOR DRIVING DEVICE FOR NATURAL GAS LIQUEFYING PLANT

摘要

PURPOSE: To achieve a reduction in operation cost and equipment costs by converting an excess of power of a gas turbine to electric power by a motor when the power generated by a gas turbine is greater in operating conditions as compared with a necessary power of a compressor. CONSTITUTION: A gas turbine 4 and a synchronous motor 5 doubling an AC power generator as auxiliary motor are linked to a propane compressor 1 which pressurizes two kinds of refrigerants circulating through closed loops independent of each other. A gas turbine 6 and a synchronous motor 7 are linked to two mixed refrigerant compressors 2 and 3 connected in series. In operating conditions under which the power generated by the gas turbines 4 and 6 is larger as compared with the necessary power of the compressors 1-3 in, an excess of power of the gas turbines 4 and 6 is converted to a power by the synchronous motors 5 and 7. This enables spare parts for countering troubles involved in the gas turbines 4 and 6 thereby lowering equipment costs.