高压含蜡油气集输管道蜡晶与水合物共存条件模拟分析  

Simulation analysis of the coexistence conditions of wax crystal and hydrate in high-pressure waxy oil and gas gathering and transportation pipeline

作　　者：宋学华 陈玲 吴燕 杨航 罗金华 敬加强[2] SONG Xuehua;CHEN Ling;WU Yan;YANG Hang;LUO Jinhua;JING Jiaqiang(Engineering Technology Research Institute of Xinjiang Oilfield Company,Karamay Xinjiang 834099,China;Oil&Gas Fire Protection Key Laboratory of Sichuan Province,Southwest Petroleum University,Chengdu,Sichuan 610500,China)

机构地区：[1]新疆油田公司工程技术研究院,新疆克拉玛依834099 [2]西南石油大学油气消防四川省重点实验室,四川成都610500

出　　处：《中国海上油气》2022年第5期221-228,共8页China Offshore Oil and Gas

基　　金：国家自然科学基金项目“深水蜡晶与水合物多相混输管道固相沉积与安全输运机制(U19B2012)”部分研究成果。

摘　　要：高压含蜡油气集输过程中,蜡晶和水合物等固相物可能同时出现并耦合堵塞管道,明确二者共存条件对集输安全运行至关重要。结合气固与液固相平衡最新理论,建立油气体系水合物生成与析蜡条件的预测模型,采用MATLAB编写相应的水合物生成条件预测PHFC与析蜡温度预测PWPT功能模块并验证模型的可靠性;以AGL油气集输海管为研究对象,计算并绘制水合物形成与蜡晶析出的温度-压力曲线,结合沿线温度与压力分布,由此直观地确定其固相生成条件。结果表明,功能模块PHFC与PWPT预测结果的相对误差分别为0.13%~1.55%与0.04%~1.14%;距AGL管线起点6.65 km的管段内无固相生成,但在距起点6.65 km和9.15 km处,先后开始出现蜡晶和水合物,在距起点9.15 km到终点的管段内有明显的水合物与蜡晶共存。高压油气集输管道理论上存在水合物与蜡共晶的安全隐患,应采取相应的防控措施,以保障其流动安全。本文研究理论及方法可供深水及陆地高压油气混输管道固相沉积风险识别与流动保障方案制定参考。During the gathering and transportation of high-pressure waxy oil and gas, solid phases such as wax crystals and hydrates may simultaneously appear and couple to block the pipeline, so it is very important to identify their coexistence conditions for safe operation of gathering and transportation. Combined with the latest theory of gas-solid and liquid-solid equilibrium, the prediction models of hydrate formation and wax precipitation conditions in oil and gas system are established. Their corresponding function modules of PHFC(Prediction of Hydrate Formation Conditions) and PWPT(Prediction of Wax Precipitation Temperature) are written by MATLAB, and their reliability is verified. Taking the AGL subsea pipeline of oil and gas gathering and transportation as a research project, the temperature-pressure curves of hydrate formation and wax crystal precipitation were calculated and drawn, and the solid phase formation conditions could be determined visually by combining with the temperature and pressure distribution along the pipeline. The results indicate that the relative prediction errors by PHFC and PWPT function modules are 0.13%~1.55% and 0.04%~1.14%, respectively;no solid phase appears from the inlet of AGL pipeline to the position of 6.65 km away from the inlet, but wax crystals and hydrates begin to appear successively at the positions of 6.65 km and 9.15 km away from the inlet, which means that hydrates and wax crystals obviously coexist in the section from the position of 9.15 km away from the inlet to the end of the pipeline. Therefore, a waxy oil and gas pipeline operated at high pressure theoretically has potential eutectic risks between paraffinic crystals and hydrate aggregations, and corresponding prevention and control measures should be taken for its flow assurance. The theory and method studied in this paper can be used as a reference for the risk identification of solid deposition and the formulation of flow guarantee scheme for deepwater and terrestrial high-pressure oil and gas mixed transporta

关 键 词：水合物生成 蜡析出 共存条件 含蜡油气流 高压集输 

分 类 号：TE86[石油与天然气工程—油气储运工程]