Efficiency Evaluation and Experiment of Natural Gas Reciprocating Compressor

Abstract

To evaluate the efficiency level of natural gas reciprocating compressor, the various kinds of energy and efficiencies for an integral engine compressor and a separable compressor are studied on basis of its energy balance equation. The experiment setup and parameters required for calculating the energy efficiencies are provided. Experimental tests on an integral engine compressor and six separable compressors are conducted to verify the correctness of these methods. The results show two methods, that are direct procedure and indirect procedure, could be applicable to obtaining the various efficiencies of an integral engine compressor owing to their slight relative errors. In general, the efficiency of integral engine compressor is lower than that of separable compressor owing to large exhaust loss and heat rejection on gas engine, and efficient electric motor. According to the 4D rule and the principal of average, three efficiency levels of natural gas reciprocating compressor are recommended, of which the limited efficiency value of gas engine is 25%, compressor unit 85%, electric motor 60%, integral engine compressor 16% and separable compressor 45%.