土库曼斯坦某气田清管工艺优化

Pigging process optimization in the gas field in Turkmenistan

关键词:  气田  集输  工艺  清管  优化 

Key words:  gas field  gathering and transmission  process  pigging  optimization

摘要:

土库曼斯坦某气田集输采用多井集气、气液混输工艺,在处理厂集气装置终端设置2台段塞流捕集器,单台容积150 m³,设2台缓冲沉降罐,单台容积100 m³。为确保气田集气干线清管过程的安全平稳,同时复核下游段塞流捕集器和缓冲沉降罐的有效性,利用目前较为先进的多相流动态模拟软件OLGA分别对各干线的100%、75%、50%和25%输量工况下的清管工况进行动态模拟。模拟结果表明: ①气田处理厂集气装置段塞流捕集器和缓冲沉降罐容积设计合理,能保证大部分清管工况的平稳安全；②低输量工况清管前,应临时增加产量,提高管道持液能力,减少清管液量；③小产量清管过程中,应降低输量,同时控制清管速度在0.3 m/s以上,延长清管时间,充分利用下游管道排液能力,减少液体在段塞流捕集器和缓冲沉降罐内的聚集。 

Abstract:

Multiple well gas gathering and two phase transmission process have been adopted in Turkmenistan gas field. Two slug captures with 150 m³ each and two buffer and sedimentation tanks with 100 m³ each were equipped. To ensure the safety of the trunk line pigging and the efficiency of slug captures and buffer tanks, OLGA, an advanced multiphase flow dynamics simulation software, was adopted to simulate pigging condition when the trunk line capacity is 100%, 75%, 50% and 25% of the design capacity especially. The result showed that:① the volume of slug captures and buffer tanks was reasonable and the pigging safety was ensured; ②the capacity should be increased temporarily to improve liquid holding capacity and decreased pigging liquid volume before pigging when the capacity was small; ③during pigging for small flow, the capacity should be decreased and the pigging rate should be more than 0.3 m/s to increase the pigging time and make full use of the downstream discharge capacity and decrease the liquid gathering volume in slug captures and buffer tanks.