北京拟建六环天然气管道储气能力计算及调峰问题探讨

CALCULATION OF STORAGE CAPACITY AND DISCUSSION OF PEAK-SHAVING ISSUE FOR PLANNED GAS PIPELINE ALONG SIXTH RING ROAD IN BEIJING

北京规划建设管道总长度超过 10 0km的高压六环天然气管网 ,对这样高压力、长距离和多点供气管线的储气量计算和储气调峰能力进行准确计算与分析十分重要。根据城市高压外环供气特点建立了管道储气与用气负荷耦合模型 ,采用解析法求解 ,得到高压管道储气量与用气负荷关系的计算公式。又据北京市目前天然气负荷的波动规律 ,对拟建北京市高压天然气六环管道在不同压力和管径下的储气能力 ,以及门站定压和定流工况下的可用储气量进行了分析。经分析认为 ,若建设设计压力为 4 .0MPa、管径为DN80 0的六环管道 ,在保证末端工作压力、门站按定流量供气的条件下 ,能用于城市负荷调峰的天然气量约为 180× 10 4m3 ,相当于少建储气压力变化范围为 1.0～ 0 .4MPa、拥有 4个几何容积为 1× 10 4m3 球罐的储罐站 6座 。

The high-pressure pipeline system, the total length more than 1000 km., is planned to build along the sixth ring road in Beijing. It is very important to calculate and analyze the storage and peak-shaving capacity of the pipeline system accurately. According to the characteristics of high-pressure gas delivering along the ring road, the coupling model of gas storage and load is set up. With the analytical method, the calculating formula is made for the relation between gas storage and load of the high-pressure pipeline. Also, according to the recent wave law of gas load in Beijing, the storage capacity under different pressures and different pipe diameters, and the active storage volume under the conditions of constant pressure and flow at the gate station are analyzed for the planned high-pressure pipeline along the sixth ring road in Beijing. The results show if the design pressure is 4. 0 MPa. and the pipe diameter is DN 800 for the pipeline, under the conditions to guarantee the working pressure at the end and the constant gas delivering at the gate station, 180×104 m3 of gas volume can be used for the load peak - shaving, which is equivalent to 6 storage stations, each with 4 spherical tanks of 1×104 m3 whose pressure can change from 1. 0 MPa. to 0. 4 MPa. So, it can save investment and land if the design program is taken.