天然气能量计量在我国应用的可行性与实践

天然气作为清洁能源的核心价值在于其供出的发热量。由于我国天然气贸易量逐年上升且随着GB/T 22723—2008《天然气能量的测定》正式实施,天然气交接将从体积计量方式逐步转向能量计量和结算。中国石油天然气股份有限公司于2011年开始在中国石油西南油气田公司建设天然气质量控制和能量计量重点实验室,致力于我国能量计量体系的建设和推广应用。为此,从设备配置和管理、检定规程、方法标准、标准参比条件、气体标准物质、体积流量,以及发热量直接测定量值量传溯源链等方面,深入分析了我国应用能量计量的可行性,并阐述了在西气东输一线和川渝管网的应用实践。结果表明:我国目前已基本具备了实施能量计量的技术条件,整体技术水平在不断提高,可初步满足能量计量应用要求;天然气分析用气体标准物质制备、发热量间接测定、流量原级标准装置水平有待进一步提高。最后提出了6个方面的发展设想来支撑天然气能量计量的全面实施。

Practicability and application of natural gas energy determination in China

The core value of natural gas as a clean energy source is its heating value output. At present natural gas trade volume keeps rising year by year in China. As the publication and implementation of the national standard of GB/T 22723 2008 〖WTBX〗the Energy Measurement of Natural Gas,〖WTBZ〗 natural gas commercial handover will be transferred to the energy measuring and clearing from present volume metering. In view of this, a detailed analysis was first made of the practicability of natural gas energy measuring in China in the aspects of equipment allocation and management, verification regulation, method standard, reference condition, gas reference material, volume flow, and heating value direct determination traceability and transferring chain. Also, the practices of gas energy measuring were introduced in Line Two of the West to East Pipeline and gas grids in Chongqing and Sichuan areas. It was concluded that China has basically possessed the technical conditions of implementing natural gas energy measuring; such an overall technology level is continuously improving and preliminarily meets the requirement of energy measuring application; however, gas reference material preparation for natural gas analysis, heating value indirect determination, and volume flow primary standard set up still need to be improved. On this basis, proposals were presented from six aspects to support the full implement of natural gas energy measuring all over China. The Key Laboratory for Natural Gas Quality Control and Energy Measurement started to be established in 2011 by the PetroChina Southwest Oil & Gasfield Company aiming at contributing to the construction and application of natural gas energy measuring system in China.