极限工况下的管网“互联互通”改进方案

An improvement scheme of "interconnected" pipeline network under extreme working conditions

在全国天然气管道“主干互联、区域成网”(以下简称“互联互通”)基础格局逐渐形成的背景下,天然气管网规模日益扩大、管道分支和气源增加,并且分布不集中、输送方向可变,使得输气方案更加灵活,可以更好地解决某些地域的供气紧张问题;但受现有站场和设备的限制,暂不能满足某些多线组合极限工况,使得“互联互通”的初衷难以全部实现。为了使得现有的各输气干线在实现“互联互通”之后可以满足更多的多线组合工况,在分析“互联互通”背景下M管网工况变化的基础上,研发了可以进行水力仿真和压气站方案制订的计算软件,并对3种极限工况下的不同输气量情况进行了可行性试算,进而基于试算结果提出了相应的管网改进建议。研究结果表明:(1)经验证,软件计算误差满足要求;(2)在M管道某处增设压气站或在某些输气站场配置压缩机组;(3) M管网改进调整后,可以完成大部分的多线组合极限工况,真正实现“互联互通”的输气方案。结论认为,该研究成果有助于推进全国天然气管网早日实现“互联互通”。

In the background that the basic pattern of "trunk interconnection and regional network formation" of the national natural gas pipeline is formed gradually, the scale of natural gas pipeline network is expanding increasingly, and branch pipelines and gas sources is increasing. In addition, the distribution is not concentrated and the transportation direction is variable. Thus, gas transportation is more flexible and the problem of gas supply shortage in some areas can be better solved. Due to the limitation of existing stations and equipment, however, some extreme working conditions of multi-trunk combination cannot be satisfied, consequently the original intention of "inter- connection" cannot be realized completely. In order to satisfy more working conditions of multi-trunk combination after the "interconnec- tion" of existing gas transportation trunks is realized, this paper researched and developed the calculation software which can be used for hydraulic simulation and compressor station plan preparation after analyzing the change of the working conditions of the M pipeline net- work under the background of "interconnection". In addition, feasibility calculation was carried out on three extreme working conditions at different gas transportation rates. And based on the calculation results, the corresponding pipeline network improvement suggestions were proposed. And the following research results were obtained. First, it is verified that the calculation error of the software is in the required range. Second, it is suggested to add a compressor station at one certain position of M pipeline or set a compressor set at some gas stations. Third, after improvement and modification, the extreme working conditions of multi-trunk combination can be mostly completed and the "interconnected" gas transportation scheme is realized practically in the M pipeline network. In conclusion, the research results are condu- cive to promoting the realization of "interconnected" natural gas pipeline network all over the country as early as possible.