基于实时组分的天然气流量在线计量方法  

Online Measurement Method for Natural Gas Flow-rate Based on Real-time Composition

作　　者：王力 王寿喜 邓传忠[3] 李伟 高翔 WANG Li;WANG Shouxi;DENG Chuanzhong;LI Wei;GAO Xiang(School of Petroleum Engineering,Southwest Petroleum University,Chengdu,Sichuan 610500,China;College of Petroleum Engineering,Xi’an Shiyou University,Xi’an,Shaanxi 710065,China;Hainan Branch,CNOOC(China)Co.,Ltd.,Haikou,Hainan 570312,China;Xi’an PipePlus Technology Co.,Ltd.,Xi’an,Shaanxi 710065,China)

机构地区：[1]西南石油大学石油与天然气工程学院 [2]西安石油大学石油工程学院 [3]中海石油(中国)有限公司海南分公司 [4]西安石大派普特科技工程有限公司

出　　处：《西安石油大学学报（自然科学版）》2024年第4期117-123,共7页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：中海石油(中国)有限公司湛江分公司科研项目“湛江分公司南海多气源联网产供气在线仿真与调度决策系统建设(二期)”(CCL2021ZJFN0566)。

摘　　要：超声波流量计采用固定天然气组分计量标况流量,为解决与实时组分偏差影响计量精度的问题,针对SCADA系统中不同的计量实时数据条件,基于质量守恒原理,结合AGA8气体物性方程,确定了天然气标准状态体积流量和能量流量计算式,以及流量累积计量误差评价方法;设计开发了在线计量软件系统,应用于某海底管道陆上计量终端,在线分析6台超声波流量计,4个月共计15万余组计量数据。结果表明:采用固定天然气组分计量流量,导致的最大相对误差为1.02%,大于A级流量计的计量不确定度(0.85%),且计量误差与实时组分和固定组分密度差值成正比。计量相对误差分布近似满足正态分布,误差在-0.5%~0.5%的概率为98.79%。因此,采用固定天然气组分计量流量,对计量精度影响较大。提出的在线计量方法,有助于提高天然气标准状态体积流量的计量精度。In the absence of real-time composition data of natural gas,in order to improve the accuracy of ultrasonic flow meters in measuring the volume flow rate of natural gas in standard state,based on the principle of mass conservation and combined with the AGA8 gas property equation,the calculation formulas for the volume flow rate and energy flow rate of standard state natural gas,as well as the evaluation method for cumulative measurement error of the volume flow rate,were determined for different real-time measurement data conditions in the SCADA system.An online measurement software system was developed and applied to 6 ultrasonic flow meters in the onshore measurement terminal of a certain submarine pipeline.Over 150 000 sets of measurement data were obtained in 4 months.The application results show that the maximum relative error for measuring the flow rate of natural gas of fixed component using the software system is 1.02%,which is greater than the measurement uncertainty of A-level flow meters(0.85%),and the measurement error is directly proportional to the density difference of natural gas of real-time component and fixed component.The relative error is approximately a normal distribution,with a probability of 98.79% for an error between-0.5% and 0.5%.Therefore,the proposed online measurement method has lower measurement accuracy in measuring the flow rate of natural gas of fixed components,which helps to improve the measurement accuracy of the volume flow rate of standard state natural gas.

关 键 词：超声波流量计 实时天然气组分 在线计量 计量误差 误差概率分布 能量流量 

分 类 号：TE832[石油与天然气工程—油气储运工程]