Application of residual pressure power generation technology in dehydration process of natural gas J-T valve

Author of the article:LI Yinjian1, LIU Gang1, WANG Jianqin1, PU Yuanyang1, WANG Haibo1, XUE Wenqi1, LIU Wenguang1, LIN Pu1, LIU Tao2, YANG Yulin3

Author's Workplace：1. CPECC Southwest Company, Chengdu, Sichuan, 610041, China; 2. PetroChina Southwest Oil & Gasfield Company, Chengdu, Sichuan, 610051, China; 3. Shehong Oil and Gas Operation Zone in Central Sichuan, PetroChina Southwest Oil & Gasfield Company, Suining, Sichuan, 629200, China

Key Words：Utilization of residual pressure; J-T valve dehydration process; New energy; High pressure wet natural gas; Power generation

Abstract：In the natural gas dehydration process, the J-T expansion/throttling valve (hereinafter referred to as the J-T valve) is used to reduce the temperature of natural gas to meet the requirements of the dehydration process. In this process, there is a huge amount of unutilised pressure energy before and after the J-T valve. However, due to the presence of liquid in the high-pressure natural gas in the J-T valve dehydration process, the power generation technology using natural gas residual pressure has not been applied in the J-T valve dehydration process before. This article analyzes the process conversion to residual pressure power generation in the expansion project of the existing system for water and hydrocarbon dew point control. Relevant optimization measures are proposed to achieve energy conservation and emission reduction via the optimal utilization of pressure energy. This technology provides reference for the expansion of green energy utilization.