城市燃气门站压力能回收热力学分析

Thermodynamic Analysis on Recovery of Pressure Energy at the City Gas Gate Station

长输来气需在门站内经调压过程将高压燃气降到较低的压力方可送入城市燃气输配系统,节流降压过程存在压力能的损失。采用能量系统的(火用)分析法对城市门站调压过程进行热力学分析,结果表明节流阀节流降压虽能满足工艺要求,但过程的(火用)损较大,(火用)效率低,应考虑可代替节流阀的其它压力能回收设备,如透平膨胀机、涡轮机等,从而有效回收城市门站调压过程损失的压力能。

The gas from long-distance pipeline should be regulated to lower pressure before it enters the city gas distribution system.This throttling process causes a loss of pressure energy.In this paper,the exergy analysis method was adopted to carry out thermodynamic analysis of the pressure regulation at the city gas gate station.The result shows that reducing pressure by throttle valve can meet the technological requirements,but exergy loss is great and exergy efficiency is low in throttling process.So it is necessary to consider other equipments for pressure energy recovery to replace throttle valve in order to recovery the pressure energy lost in pressure regulation process.The equipments include turbo expander,turbine and so on.