液氨与成品油顺序输送过程两相流动规律研究  

Study on the two-phase flow behavior in batch transportation of liquid ammonia and product oil

作　　者：黄鑫[1] 施鸿翔 李逸龙 李卫东 尹鹏博 李臻超 滕霖 江莉龙[1] HUANG Xin;SHI Hongxiang;LI Yilong;LI Weidong;YIN Pengbo;LI Zhenchao;TENG Lin;JIANG Lilong(College of Chemical Engineering,Fuzhou University)

机构地区：[1]福州大学化工学院

出　　处：《油气储运》2024年第10期1099-1108,共10页Oil & Gas Storage and Transportation

基　　金：国家重点研发计划“氢能技术”专项资助项目“高效热化学合成氨催化剂的创制及其批量制备技术”,2021YFB4000403;国家自然科学基金创新研究群体项目“氨能源催化工程”,22221005;国家自然科学基金重点项目“基于缔合加氢机理的高性能亚纳米Ru基合成氨催化剂设计制备及应用基础研究”,22038002;国家自然科学基金青年科学基金项目“电场作用下双液滴不聚并与多液滴成链机理研究”,52204073;国家自然科学基金青年科学基金项目“干冰颗粒碰撞聚并行为的微尺度界面演化机制研究”,52204072;福建省自然科学基金项目“高强电场下复杂液滴破裂与聚并动力学机理研究”,2022J05130。

摘　　要：【目的】利用成品油管道顺序输送液氨,能够拓宽液氨的运输途径,削减运输成本,也可提高管道输送效率,以应对成品油管道低输量问题。但目前鲜有关于成品油管道顺序输送液氨工艺研究,且液氨与成品油的互不相溶性导致其混液规律与传统成品油混油规律存在差异,这给混液界面的预测和控制带来挑战。【方法】应用耦合相场法与流体控制方程,建立液氨/成品油顺序输送两相流模型,重点探究输送次序、管道流速以及管道倾角对液氨/成品油顺序输送过程两相流动规律的影响。【结果】在水平管道中,由于密度差异影响,成品油前行、液氨后行的输送次序会导致界面处出现RT(Rayleigh-Taylor)不稳定现象,两相流动易形成不连续的相分布。该工况下,流速较低时界面稳定性提高,但混液段长度较长。而在液氨前行、成品油后行的输送次序下,界面稳定性较好,即使流速较高,界面也能保持相对稳定且混液段长度较短。此外,在上坡管道中重力作用方向与流动方向相反,抑制了后行成品油嵌入液氨,界面稳定且混液段长度较短;而在下坡管道中,重力作用与流动方向相同,增强了RT不稳定性,导致界面易破裂,混液段显著增长。【结论】研究结果可为成品油管道顺序输送液氨中混液界面的预测与跟踪提供理论基础。[Objective]Batch transportation of liquid ammonia via product oil pipelines can expand transportation routes,reduce costs,and enhance pipeline efficiency to address the low throughput of existing product oil pipelines.Currently,there is little research on the batch transportation of liquid ammonia via product oil pipelines.In addition,due to the mutual insolubility of liquid ammonia and product oil,the blending behavior differs from traditional product oil blending,posing challenges for predicting and controlling the liquid blending interface.[Methods]By coupling the phase-field method with fluid control equations,a two-phase flow model for batch transportation of liquid ammonia and product oil was developed to examine how transportation sequence,pipeline flow rate,and pipeline dip angle affect the two-phase flow behavior during batch transportation.[Results]In the horizontal pipeline,the sequence of transporting“product oil before liquid ammonia”would cause Rayleigh-Taylor(RT)instability at the interface due to density difference,resulting in a discontinuous phase distribution in the two-phase flow.Under this condition,the stability at the interface was improved at low flow rates,but the length of the blending section was long.However,in the transportation sequence of“liquid ammonia before product oil”,the stability at the interface could be maintained even at high flow rates,resulting in a shorter blending section.In addition,in the up-dip pipeline,gravity opposed the flow,inhibiting the entrainment of product oil into liquid ammonia,thus maintaining a stable interface and a short blending section.In contrast,in the down-dip pipeline,gravity aligned with the flow,increasing RT instability and leading to interface fractures and a significant increase of the blending section.[Conclusion]The results provide a theoretical basis for predicting and tracking the blending interface during the batch transportation of liquid ammonia in product oil pipelines.

关 键 词：液氨管输 成品油管道 混液界面 相场法 

分 类 号：TE832[石油与天然气工程—油气储运工程]