Research on Gas Stringer Automatic Deliquification in Sulige Gas Field

Abstract

Managing numerous gas stringers reasonably and effectively is an arduous work. A system of gas stringer automatic deliquification is presented that uses simulation of opening wells manually and automatic liquid loading identification as its basis for control logic. Technical effects of automatic deliquification in field test are compared to the operations of manual intermittent production and using foam. The new approaches are based on the research on the intermittency of the gas stringer. It considers the factors of tubing pressure, casing pressure, gas production rate, liquid producing, etc. Three algorithms are provided to reach a better effect of deliquification including operation of intermittency, operation of using foam, and operation of combination. Accordingly, reasonable intermittent rules can be set according to the characteristics of pressure and production rate. Simultaneously, fair concentration and amount can be determined as well. Furthermore, the mode of self-diagnosis of upper computer is described. Hardware and software for automatic opening well and automatic injecting foam are development, as well as remote control platform. The effects of using system of gas stringer automatic deliquification are compared to manual intermittent production and manual foam that have been traditionally applied. Four field case studies are presented. Field test in Sulige gas field shows that the average difference between tubing pressure and casing pressure decrease by 0.8MPa and gas production rate increase by 0.2×104m3/d. Meanwhile, the effects of liquid loading are reduced. The most significant effect is that automatic deliquification can make the operations timely and even finely. This is important because in some cases the proper rules are hard to execute for manpower. Besides, costs and labor intensity are reduced. The novelty of system of gas stringer automatic deliquification is in the ability to improve the accuracy and timeliness of operations. Through the research of gas stringer automatic deliquification, fine management of the gas well could be achieved, and the automation level of the gas field could be promoted. It will benefit tens of thousands of gas stringers in the world.