A Study On A Time-Division Gas Flow Adjustment System Of Reciprocating Compressor

Piston compressors have a wide range of applications in the petrochemical industry, one of the pillar industries in the national economy. Along with the changes in the petro-chemical industry and the scarcity of energy, enterprises not only require the displacement piston compressor can be adjusted in a larger range, but also require the compressor can reduce energy consumption proportional to gas flow reduction. Many gas flow adjustment technologies has been developed rapidly for energy saving.Based on the analysis and study of the current reciprocating compressor structure, working principle and gas flow adjustment technology, together with consideration on the characteristics of the reciprocating compressor used in the petrochemical industry, with a view of saving energy, the author proposed a new technique - a time-division gas flow adjustment technique, which is an refinement of the full stroke suction-valve-open gas flow adjustment technique.In principle, this paper analyzed the feasibility of the time-division gas flow adjustment technique applied in high-power reciprocating compressor, compared this technique with other previous techniques. The author performed a structure design of the time-division gas flow adjustment system for a reciprocating compressor.The author made choice of the relevant hardware, designed a PLC based control system for a time-division gas flow adjustment system using Proportional-Integral-Derivative controllers, and implemented the control system using a SCADA (Supervision, Control and Data Acquisition) figuration software.This control system has been applied to a two piston, two stage gas reciprocating compressor and achieved control of gas flow rate, inter-stage pressure and out flow gas temperature.