三气合采固态流化气举分层调控工具设计与实验  

Design and experimental study of stratified control tool for solid fluidization and gas lift in three-gas combined mining

作　　者：唐洋[1,2,3] 张玉林 付强 王国荣[1,2] TANG Yang;ZHANG Yulin;FU Qiang;WANG Guorong(School of Mechatronic Engineering,Southwest Petroleum University,Chengdu,Sichuan 610500,China;Energy Equipment Institute,Southwest Petroleum University,Chengdu,Sichuan 610500,China;National Key Laboratory of Oil&Gas Reservoir Geology and Exploitation//Southwest Petroleum University,Chengdu,Sichuan 610500,China;CNOOC Research Institute Co.,Ltd.,Beijing 100028,China)

机构地区：[1]西南石油大学机电工程学院,四川省成都市610500 [2]西南石油大学能源装备研究院,四川省成都市610500 [3]油气藏地质及开发工程全国重点实验室·西南石油大学,四川省成都市610500 [4]中国海油研究总院有限责任公司

出　　处：《天然气工业》2024年第12期94-104,共11页Natural Gas Industry

基　　金：国家重点研发计划项目“多气分层合采及调控机制”(编号:2021YFC2800903);四川省科技计划项目“深水双层管动力学研究及应用”(编号:2023NSFSC1980)。

摘　　要：三气合采是实现海域天然气水合物(以下简称水合物)早期商业性开发的有效途径之一,但现有海洋油气井下配产工具无法实现对三气合采中各层位产出天然气压力及流量的分层与精细调控,无法满足三气合采中高效气举助排固态流化水合物浆液的需求。为此,针对井下配产工具难以满足该工艺中对不同层位天然气进行分层调控的需求问题,提出了一种水合物固态流化气举分层调控工程实施方案,发明了一种采用笼套段与固定油嘴组成的二级节流结构的井下分层调控工具,可实现根据生产需求通过调节分层调控工具阀芯模块对天然气压力、流量的精确调控。研究结果表明:①井下分层调控工具阀芯模块采用笼套端与固定油嘴组成的多级节流结构,具有降压性能好和降温幅度适中的优点;②随着出口压力的增大,出口气体质量流量在13.0 kg/s的小范围内波动,当出口压力达到13 MPa,阀芯内部天然气最低温度低于水合物生成温度阈值;③随着阀芯开度变化,阀芯内部气体质量流量和体积流量变化接近线性变化,调控工具能够在高压环境下实现对天然气流量的精细调控。结论认为,发明的井下分层调控工具能够满足对天然气流量进行线性精细调控的需求,满足了三气合采中对固态流化水合物浆液高效气举助排的技术需求,并可为我国实现水合物商业化开发提供工程技术装备的支撑。Three-gas combined mining is one of the effective ways to realize early commercial development of offshore natural gas hydrate.However,the existing downhole production allocators used for offshore oil and gas wells are unable to realize the stratified and precise control of the pressure and flow rate of natural gas produced from each layer in three-gas combined mining,and nor can meet the need of efficient gas lift assisted drainage of solid fluidized hydrate slurry.To solve the problem that downhole production allocators can hardly meet the need of stratified control of natural gas in different layers,this paper proposes an implementation plan of stratified control engineering for solid fluidization and gas lift of natural gas hydrate,and invents a downhole stratified control tool with two-stage throttling structure composed of cage section and fixed choke,which can realize the accurate control of natural gas pressure and flow rate by regulating the spool module of stratified control tool according to the production demand.And the following research results are obtained.First,the multi-stage throttling structure consisting of cage section and fixed choke in the spool module of downhole stratified control tool has the advantages of good depressurization performance and moderate cooling range.Second,with the increase of outlet pressure,the gas mass flow rate at the outlet fluctuates within a small range of 13.0 kg/s.When the outlet pressure reaches 13 MPa,the lowest temperature of natural gas inside the valve core is lower than the threshold hydrate formation temperature.Third,with the change of spool opening,the change of gas mass flow rate and volume flow rate inside the valve core is approximately linear,so that the control tool can achieve an accurate control of natural gas flow rate under a high pressure environment.In conclusion,the downhole stratified control tool invented in this study can meet the need of linear accurate control of natural gas flow rate,as well as the technical need of efficient gas lift

关 键 词：海洋油气井 天然气水合物 三气合采 分层调控 调控工具 

分 类 号：TE931[石油与天然气工程—石油机械设备]