天然气长输管道并行跨接方案比选

Comparison of the crossover schemes for the parallel long-distance natural gas pipeline

中石化石油工程设计有限公司新疆分公司

Xinjiang Branch, SINOPEC Petroleum Engineering Corporation

天然气管道; 站场跨接; 阀室跨接; 方案研究

natural gas pipeline; crossover between compressor stations; crossover between valve chambers; scheme research

针对我国天然气长距离管道日益增多,独立管道出现事故频繁、管道停输等问题,调研了国内外天然气长输管道并行跨接规范及管道跨接方案设置技术,在X 线与Y 线并行管道进行了4 种跨接方案应用,并进行了管道受损等效对比研究。结果表明:跨接阀数量与年系统降量呈反比,随着跨接阀数量的增加,系统年失效频率增加,年挽回的损失气量相应降低,导致挽回的损失气量与增加投资的比值变小。两座站间设置1 座跨接阀室的跨接方案性价比最高,这说明在设置跨接方案时,存在一个最优的跨接阀数量。建议在X 线与Y 线站间设置1 座跨接阀室,采用阀前、阀后均设跨接管的设计方案,该方案能提高管道事故应急调配能力,并能保障整个管道系统的供气可靠性,设计方案较为经济合理。

With the increase of long-distance natural gas pipelines in China, single pipeline is vulnerable to frequent accident, shutdown or other problems. Through reviewing the crossover specifications for long-distance parallel natural gas pipelines and related crossover techniques, this paper proposes four crossover schemes for the parallel X and Y Pipelines and makes equivalent contrast research on pipeline. The result shows that there is an inverse correlation between the number of crossover valves and the annual system failure reduction. With the increase of the number of crossover valves, the annual failure frequency of system increases and the redemptive lost gas volume per year decreases, which leads to a smaller ratio between the redemptive lost gas volume and the increased investment. The crossover scheme with 1 crossover valve chamber between 2 compressor stations reveals the best cost performance, which means that there are an optimum number of crossover valves under a crossover scheme. For the parallel X and Y Pipelines, a scheme of 1 valve chamber between compressor stations with both crossover pipes before and after valves is recommended. This scheme can improve the emergency allocation capability of the pipeline and guarantee the reliability of the whole system. It is economically reasonable.