摘要
承压堵漏技术主要应用于孔隙和裂缝比较发育的多套压力体系并存的长裸眼井段,塔河油田盐膏层上部长裸眼地层承压堵漏困难,多数表现在承压堵漏施工周期长,堵漏需反复多次。针对深井盐膏层地质特点,开发出适合塔河地质特点的巨厚纯盐层、复合膏盐层的承压堵漏工艺:针对粗砂岩、砂砾岩为主的高渗透层,以高浓度细、超细颗粒复合堵剂为主,配合中粗颗粒,以便在出现压裂时起架桥作用;针对以细砂岩、粉砂岩为主的中低渗透层,以适当浓度细、超细颗粒复合堵剂为主,也可加入一定量的中粗颗粒堵剂,以便出现压裂时起架桥作用;对于以泥岩为主的超低渗透层,其破漏压力(当量密度)一般可达1.80g/cm3以上,以适当浓度细、中粗颗粒复合堵剂为主,作预防压裂时堵漏;对于裂隙、破碎地层或地质不整合面,易发生裂缝性漏失,应以高浓度中粗颗粒堵剂架桥,细、超细颗粒复合堵剂作充填,并合理搭配。该承压堵漏工艺先后在塔河油田主体区块的膏盐层井S105、S112-1等井进行了应用。
The technology of mud loss control under pressure is mainly used in long open hole sections with multiple developed pore and fractures pressure systems.But the application of the technology has some difficulties in the upper formations of salt-gypsum of Tahe Oilfield： long operation cycle for many times.According to the geological characteristics of the salt-gypsum layers in the deep well,the technology suitable for tremendous-thick net salt layer and composite salt-gypsum layers in Tahe Oilfield is developed.For the high-permeability formations dominated by gritrock and glutenite,composite seepage control material of high-concentration fine-super fine grain may be used mainly together with middle-coarse grain,which will put up bridge when fracturing.For middle-low permeability formations dominated by fine sandstone and silt,composite seepage control material of moderate-concentration fine-super fine grain may be used mainly together with middle-coarse grain.For the super-low permeability formations dominated by shale,mud loss pressure is usually more than 1.80g/cm3,composite seepage control material of moderate-concentration fine-middle grain may be used mainly for mud loss control in time.For cracked formations or unconformity surface,composite seepage control material of high-concentration middle-coarse grain may be used mainly together with fine-super fine grain so as to prevent loss by fractures.The technology is applied in well S105,S112-1,AT5 and others in the salt-gypsum layer of main blocks in Tahe Oilfield.
出处
《中外能源》
CAS
2011年第1期74-79,共6页
Sino-Global Energy
关键词
堵漏
长裸眼
盐膏层
复合桥塞
颗粒配比
mud loss control
long open hole
salt-gypsum layer
composite bridge plug
particle ratio
