基于IOW的高含硫气田集输管网操作风险评估

Operation risk assessment based on IOW of flow and gathering lines in a high-sulfur natural gas field

高含硫气田开发安全风险极大,确保其集输管网安全经济稳定运行具有重要意义。为此,利用完整性操作窗口(IOW)技术对其集输管网进行了操作风险分析,首先,把管网输入输出空间划分为正常操作、安全警戒、安全危险、灾难4个区域,并根据管道承受强度、天然气水合物生成温度、管道腐蚀影响等因素确定出了管道中天然气压力、温度、流速为输出区域敏感变量,集气站供气压力、供气温度、供气量为输入区域敏感变量;然后以相关标准规范、工程实践成果等来确定输出区域敏感变量不同输出区域的边界;最后,利用HYSYS软件建立集输系统的工艺模型,基于确定的输出区域变量边界,按管网输入输出区域的映射关系得到了输入区域变量的边界,从而可根据集输管网运行参数进行操作风险等级评估。结果表明:采用IOW技术能够对集输管网工艺状态进行危险等级划分,可为制定集输管网运行策略提供参考。

To ensure the safe,steady and cost-effective operation of gathering and flow lines is of great significance to the prevention of high risks in the development of a high-sulfur gas field.Therefore,we applied the IOW（integrity operating window）technology to the operation risk assessment in this subject.First,all the involved input and output space in the gathering and flow lines was divided into normal operation,safety alarm,safety hazard,and disaster-prone areas.Then,according to the pipeline strength,natural gas hydrate formation temperature and pipeline corrosion factors,the gas pressure,gas temperature,and gas flow rate in the lines were identified as the sensitive variables of output zones,while the gas pressure,gas temperature,and gas flow volume from natural gas gathering stations were identified as the sensitive variables of input zones.Furthermore,in light of the relevant standards and specifications,engineering practices,etc.,different output zone boundaries of sensitive variables were classified.Finally,the process model of gathering and flow line system was established by use of HYSYS software.Based on the determined output zone boundaries,the input zone boundaries of the sensitive variables were also determined upon the mapping between input and output zones of the line system.The results showed that the IOW technology can be used to assess the risk levels of process status of lines,which provides helpful information for developing appropriate operation strategies of gathering and flow line systems in a gas field.