一种采用直井井组细分层压裂注热水开采天然气水合物的工艺方案  

Study on the Exploiting Technology of Natural Gas Hydrate Using Vertical Well Group with Separate Stratified Fracturing and Hot Water Injecting

作　　者：罗天雨[1] LUO Tian-yu(Guangdong University of Petrochemical Technology,Maoming 525000,Guangdong Province,China)

机构地区：[1]广东石油化工学院,广东茂名525000

出　　处：《海洋技术学报》2020年第2期98-104,共7页Journal of Ocean Technology

基　　金：广东石油化工学院人才引进资助项目“水溶性压裂暂堵剂研制及配套工艺研究”(517176)。

摘　　要：在海底的沉积物或冻土中,赋存有大量的天然气水合物,这是一种适于未来开发利用的能源,具有优质、洁净、资源量大等优势。由于开采对象的复杂性,在世界范围内,开采技术整体上尚无成熟配套,面临着单井产量低、连续时间短、经济效益差等缺陷,因此需要针对天然气水合物储层研究高效开采的工艺方法。本研究针对有一定渗流能力的水合物储层,提出了一种采用直井井组细分层压裂注热水开采的工艺技术:(1)依据地质资料,对目标储层布置直井井组,直井分为注水井与生产井,通过井组注入热水开采提高采收率;(2)采用套管射孔完井,套管内下入筛管防砂;(3)对注水井进行不加砂细分层压裂,采出井不压裂;(4)至生产效果变差时,开始通过注水井注入热水激发,从生产井生产天然气;(5)采用海水源热泵技术提供热水,就地取材,经济高效;(6)对采出井进行注入固结剂作业,采用系统防砂技术;(7)建立数学模型进行模拟,结果表明,细分层压裂注热水开发方案能大幅提高产量。该工艺能够提高储层的加热效率与受热体积,减少出砂的可能性,大幅提高储层生产天然气的产量与持续时间,进而提高经济效益。In the middle of undersea deposition or frozen soil,there is plenty of natural gas hydrate,which is deemed as a sort of high-quality and clean energy sources.Owing to the complexity of exploitation projects,the exploitation technologies are still immature in the world.Single well output is low,the run-on time is short,and economic performance is poor.Therefore,it is necessary to study advanced technological methods used to efficiently exploit natural gas hydrate reservoirs.Aiming at natural gas hydrate reservoirs with certain percolation capacity,this study proposes a technology with separate stratified fracturing and hot water injection using straight well groups.(1)According to the geological data,the target reservoir is exploited with straight well groups,which are divided into injection wells and production wells,so as to enhance recovery through injection of hot water.(2)The casing perforating completion method is adopted,and screen is used inside of casing for sand controlling.(3)Separate stratified hydraulic fracturing is carried out on the injection well.In this way,production wells will not be fractured.(4)When the production effect becomes worse,hot water is injected to stimulate the hydrate reservoir through the injection well,and natural gas is produced from the production well.(5)The technology of sea water source heating pump can be adopted to provide hot water with local materials,which is economical and efficient.(6)Systematic sand controlling technology is adopted for production.(7)A mathematical model is established for simulation,and the results show that the development scheme of fine stratified fracturing with hot water injection can greatly increase the productivity.This process can improve the heating efficiency and heated reservoir volume,reduce the possibility of sand production,and greatly improve the production and duration of natural gas,as well as improve economic benefits.

关 键 词：天然气水合物 开采技术 直井井组 细分层压裂 海水源热泵 储层固结 系统防砂 

分 类 号：TE355[石油与天然气工程—油气田开发工程]