管网设施公平开放下的LNG管道代输模式问题及对策

Problems in LNG Pipeline Transportation Mode under Fair Opening of Pipeline Network Facilities and Their Countermeasures

随着天然气管网设施公平开放的持续深入和LNG贸易的兴盛,LNG消费企业直接采购LNG,使用管道企业的LNG接收站卸货、气化,通过管道外输至下载点的LNG管道代输模式将成为天然气运输的重要方式之一。此模式能够充分利用管道运输的优势,实现LNG消费企业、管道企业以及天然气用户三方共赢。LNG管道代输模式下,LNG气化后天然气气质应满足相关规范标准的要求。通过分析认为,LNG管道代输存在3个计量交接界面,并对每个计量交接界面推荐计量交接方式。针对LNG代输管输费计费方式,提出管输距离应以LNG接收站与天然气下载点的管道距离来测算,管输流向应服从天然气大管网整体流向。管道企业应通过优化工艺流向、压缩机组运行方式等,在保证包括LNG代输在内供给侧天然气顺利上载、需求侧顺利下载的同时,实现管网总耗能最低。

With the continuous deepening of the fair opening of natural gas pipeline network facilities and the prosperity of LNG trade,it will become one of the important ways of natural gas transportation that LNG consumer enterprises directly purchase LNG,use the LNG receiving station of pipeline enterprises to unload and gasify.This mode can make full use of the advantages of pipeline transporta⁃tion to achieve a co-win of LNG consumers,pipeline enterprises and natural gas users.Under the LNG pipeline transportation mode,the natural gas quality after LNG gasification should meet the requirements of relevant specifications and standards.Through analysis,it is considered that there are three metering interfaces for LNG pipeline transportation,and the metering mode is recommended for each metering interface.According to the charging method of LNG pipeline transportation fee,it is proposed that the pipeline transpor⁃tation distance should be calculated by the distance between LNG receiving station and NG download point,and the pipeline transporta⁃tion flow direction should follow the overall flow direction of large natural gas pipeline network.Pipeline enterprises should optimize the process flow direction and the operation mode of compressor units to ensure the smooth loading of natural gas(including LNG)on the supply side and the smooth downloading of natural gas on the demand side,while minimize the total energy consumption of pipeline network.