摘要
海洋天然气水合物试采过程中存在水合物产量低,在射流破碎工况下沉沙严重、返出液极少甚至失返等问题。为提高水合物产量,充分利用开采设备的价值,基于天然气水合物、浅层气、天然气藏纵向立体开发思想,提出了一种三气合采分层调控工程实施方案。基于气液两相流理论,考虑水合物自分解行为以及固相颗粒有效运移条件,建立了天然气水合物固态流化不同开采阶段下天然气助排举升水合物浆液数学模型,并对气液流动机理相关数学模型进行求解和验证,最终得到了三气合采分层调控工艺中天然气助排举升水合物浆液工艺图版。在水平段钻进阶段,钻井液流量大于13 L/s时,不需要额外注入气相即可保证固相颗粒的有效运移,注入气体可加速固相颗粒的运移,根据钻井液的泵入量,气相注入量范围为0~67 L/s;水合物破碎回收阶段,破碎流量在49~55 L/s内,不需要额外注入气相即可保证固相颗粒的有效运移,在水合物破碎流量范围内,气相注入量范围为0~129 L/s。该研究为提高水合物开采产量,加快实现水合物早期商业化开采,推进中国“双碳”战略目标的实现提供了参考和帮助。
In offshore natural gas hydrate trial production,challenges such as low hydrate yield,severe sand setting under jet-breaking conditions,and minimal or even no liquid return are commonly encountered.To enhance hydrate production and maximize the utilization of extraction equipment,this study proposes a layered regulation engineering scheme for three-gas co-production,integrating the vertical and spatial exploitation of natural gas hydrate,shallow gas,and natural gas reservoirs.Based on the gas-liquid two-phase flow theory,and considering hydrate self-decomposition and effective transport of solid particles,a mathematical model of hydrate slurry lift assisted by natural gas is developed for different extraction stages of solid-state hydrate fluidization.The mathematical model for gas-liquid flow mechanisms is solved and validated,resulting in a technical chart for hydrate slurry assisted by natural gas drainage and lifting within the layered regulation process of three-gas co-production.In the horizontal drilling phase,when the drilling fluid flow exceeds 13 L/s,effective transport of solid particles is ensured without additional gas injection.Gas injection can be used to accelerate solid particle transport,with the gas injection volume ranging from 0 to 67 L/s depending on the drilling fluid pumping volume.During the hydrate fragmentation recovery phase,effective transport of solid particles is achieved within a fragmentation flow range of 49~55 L/s without additional gas injection.Within this range,the gas injection volume varies between 0 and 129 L/s.This research provides insights to improve hydrate production,expedite early-stage commercial hydrate exploitation,and support China’s“dual carbon”strategic goals.
作者
唐洋
徐嘉庆
付强
张吴镝
王国荣
TANG Yang;XU Jiaqing;FU Qiang;ZHANG Wudi;WANG Guorong(School of Mechanical Engineering,Southwest Petroleum University,Chengdu 610500,China;Energy Equipment Institute,Southwest Petroleum University,Chengdu 610500,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu 610500,China;Huairou Laboratory,Beijing 101407;CNOOC Research Institute Co.,Ltd.,Beijing 100028,China)
出处
《海洋工程》
北大核心
2025年第2期141-154,共14页
The Ocean Engineering
基金
国家重点研发计划资助项目(2021YFC2800903)
四川省自然科学基金项目(2025ZNSFSC0442)
国家自然科学基金资助项目(52004235)
天然气水合物国家重点实验室开放基金项目(2022-KFJJ-SHW)。
关键词
三气合采
天然气水合物
气液两相流
水合物浆液
注气量
three-gas co-production
natural gas hydrate
gas-liquid two-phase flow
hydrate slurry
gas injection volume
