Simulation of natural gas transmission pipeline network system performance

Simulation has proven to be an effective tool for analyzing pipeline network systems （PNS） in order to determine the design and operational variables which are essential for evaluating the performance of the system. This paper discusses the use of simulation for performance analysis of transmission PNS. A simulation model was developed for determining flow and pressure variables for different configuration of PNS. The mathematical formulation for the simulation model was derived based on the principles of energy conservation, mass balance, and compressor characteristics. For the determination of the pressure and flow variables, solution procedure was developed based on iterative Newton Raphson scheme and implemented using visual C＋＋6. Evaluations of the simulation model with the existing pipeline network system showed that the model enabled to determine the operational variables with less than ten iterations. The performances of the compressor working in the pipeline network system xvhich includes energy consumption, compression ratio and discharge pressure were evaluated to meet pressure requirements ranging from 4000-5000 kPa at various speed. Results of the analyses from the simulation indicated that the model could be used for performance analysis to assist decisions regarding the design and optimal operations of transmission PNS.

塔河油田集气总站计量输差分析及控制

天然气输差是控制输气成本的一个关键指标,可分为计量输差和漏失输差两大类。在实际生产中,由于产生输差的原因非常复杂多变,往往导致天然气计量交接不能满足精度要求。因此,找出影响其计量误差和提出改进措施有着重要的意义。以塔河油田集气总站为例,从旋进旋涡流量计和超声流量计的原理特点、现场应用情况、用户负荷、外部干扰等4个主要方面对引起计量输差的因素进行了探讨,并提出了6项控制措施。其中包括通过现场流程改造,有效解决了FT301超声流量计反向计量不准确的问题,使该站的站输差从5.26%降低到了0.68%,取得了较好的效果。

基于智能监控的天然气场站火灾防控系统

结合天然气泄漏智能监控技术、自动控制技术及雨雾炮稀释降温技术,设计了一套天然气集输场站火灾主动防控系统。系统由现场监测装置、控制中心和雨雾炮组成,其中现场监测装置由催化燃烧式传感器和火灾探测器组成。雨雾炮性能测试和系统响应时间测试结果表明,监控装置反应灵敏,系统响应时间快,雨雾利用率高,能够有效保障天然气集输场站人员安全及天然气正常集输,具有良好的应用前景。