输气管道气体置换的中间注氮方法
A middle nitrogen injection method in the gas displacement for gas pipeline
闵海鹏 1谢雪梅 1赵翔 1唐红军1
作者信息
- 1. 陕西省天然气股份有限公司,陕西西安710016
- 折叠
摘要
在役天然气长输管道停输检修或改线碰口动火作业中,为了确保动火施工的安全,需要对动火段管道内天然气放空后用氮气置换,但线路截断阀内漏会造成氮气置换天然气时发生混气,无法做到置换彻底.由此提出采用中间注氮方法,即在管道放空至微正压后,在碰口部位不动火开一注氮口,自管道中间向两端进行氮气置换.在陕西省天然气长输管道碰口作业中的实践应用,表明:与传统注氮置换方法工艺相比,中间注氮方法可以有效避免线路截断阀内漏带来的带气动火风险,做到置换彻底,动火安全.
Abstract
In the hot work of long-distance gas pipeline in service which is shut down for inspection or tie-in in route change,gas in the treated pipeline section should be vented and then displaced by nitrogen,for purpose of work safety.The inner leakage of block valve in the pipeline may cause gas mixing when the natural gas is displaced by nitrogen,so that the natural gas cannot be completely replaced.In this case,the middle nitrogen injection method is proposed,namely,after the pipeline is vented to slightly positive pressure,an injection nozzle is opened without hot work at the connection location,and then the nitrogen is injected to displace gas from the pipeline center to both ends.The practical application in a longdistance gas pipeline in Shaanxi Province shows that,comparing with conventional nitrogen injection method,the middle nitrogen injection method can effectively avoid the risk of on-line hot work caused by the inner leakage of block valve in the pipeline,and consequently realize thorough displacement under safe hot work.
关键词
天然气/管道/中间注氮/置换Key words
natural gas/pipeline/middle nitrogen injection/displacement引用本文复制引用
出版年
2015
NETL
NSTL
维普
万方数据