气相管壁水合物沉积层分解破裂特性研究  

Study on decomposition and fracture characteristics of hydrate deposition layer on gas-phase pipeline wall

作　　者：张佳璐 景红 魏江东[2] 徐悦[3] 朱弘宇 王武昌[3] 李玉星[3] ZHANG Jialu;JING Hong;WEI Jiangdong;XU Yue;ZHU Hongyu;WANG Wuchang;LI Yuxing(Petroleum Engineering Technology Research Institute,SINOPEC Shanghai Offshore Oil&Gas Branch,Shanghai 200120,China;PetroChina Planning and Engineering Institute,Beijing 100083,China;Shandong Key Laboratory of Oil Gas Storage and Transportation safety,College of Pipeline and Civil Engineering,China University of Petroleum(East China),Qingdao 266580,Shandong,China)

机构地区：[1]中国石油化工股份有限公司上海海洋油气分公司石油工程技术研究院,上海200120 [2]中国石油天然气股份有限公司规划总院,北京100083 [3]中国石油大学(华东)山东省油气储运安全省级重点实验室,储运与建筑工程学院,山东青岛266580

出　　处：《低碳化学与化工》2023年第6期163-169,共7页Low-Carbon Chemistry and Chemical Engineering

基　　金：国家自然科学基金重大项目(51991363);国家自然科学基金(51974349);国家自然科学基金联合基金(U19B2012)。

摘　　要：针对流道内气相管壁天然气水合物(以下简称“水合物”)沉积层的分解破裂特性进行研究,明确其分解破裂机制,进而为水合物流动安全控制提供依据。实验中,在摇晃测试段中生成沉积层之后,采取降压法对其分解。观察宏观形态变化并计算分解速率,同时通过探针采集到的电压信号的变化来反映局部的分解情况。实验结果表明,基于电压信号的检测方法可以作为一种新型监测分解的手段。降压分解时沉积层以存在脱落现象的消融模式分解,在3种降压速率(0.010 MPa/s、0.026 MPa/s和0.056 MPa/s)下沉积层分解时都会有冰生成,当降压速率增大到0.026~0.056 MPa/s时,冰-水合物混合沉积层会从壁面随机位置处脱落,冰-水合物混合沉积层的脱落速率随着降压速率的增大而增大,存在冰堵塞的危险。最后根据实验现象总结出了沉积层破裂脱落的原因是分解过程中沉积层结构变化和气体冲击,而气体冲击是造成破裂脱落的主要原因。The decomposition and fracture characteristics of the natural gas hydrate(hereinafter referred to as“hydrate”)deposit layer in the gas phase tube wall in the flow channel were studied,and its decomposition and fracture mechanism was defined,so as to provide a basis for the safety control of hydrate flow.In the process of the experiment,after the deposition layer was formed in the shaking test section,it was decomposed by depressurization method.The macroscopic morphological changes was observed and the decomposition rate was calculated,and the local decomposition was reflected by the change of the voltage signal collected by the probe.The experimental results show that the electrical signal-based detection method can be used as a novel means of monitoring decomposition.The deposition layer is decomposed in an ablation mode with shedding phenomena during depressurisation.During decompression,the sediment is decomposed in ablative mode with ablative phenomenon,and the ice is formed when the sediment decomposes at three decompression rates(0.010 MPa/s,0.026 MPa/s and 0.056 MPa/s).When the depressurization rates increase to 0.026 MPa/s to 0.056 MPa/s,the ice-hydrate mixed deposition layer falls off from the random location of the pipe wall.The shedding rate of the ice-hydrate mixed deposition layer increases with the depressurisation rate,bringing a risk of ice jamming.Finally,based on the experimental phenomena,the causes of shedding are summarized.One is the change of the structure of the deposition layer during the decomposition process.The other is the gas impact,which is the main reason for the shedding.

关 键 词：天然气水合物 水合物沉积层 分解破裂特性 破裂脱落机制 

分 类 号：TE832[石油与天然气工程—油气储运工程]