摘要
克拉玛依—东区低渗透砾岩油藏经过多年开采之后,油井产量明显下降,主要原因是油井的近井地带出现堵塞,降低了油井原油向底的运移能力,堵塞物成份多以有机物和无机物为主,生产时间较短的油井堵塞物主要以有机物为主,其中蜡质、胶质、沥青的含量占60%以上;而生产时间较长的油井堵塞物以有机物和无机物并存,其中垢物的主要成分为CaCO3、Ca SO4、BaSO4和SiO2,堵塞主要集中在近井地带3~5 m内。对于注水井中造成注水效率下降的堵塞物,主要以铁盐、亚铁盐和细菌以及由水敏、速敏共同作用形成的,并且堵塞半径达到5 m以上。针对不同井况的堵塞特征,室内筛选一种以ZJ-UB生物酸为主体的解堵配方体系,具有溶蜡溶垢、降低油层孔隙表界张力等多项功能,经过一系列现场实验,取得了良好的现场应用效果。
The oil well production in the low-permeability conglomerate reservoirs in east Karamay has obviously dropped after years of production. The main reason is the plugging appeared near the wellbore,reducing the oil flowing into the well bottom. The plugging is mainly composed of organic and inorganic materials. For wells with fewer production years,the plugging is mainly consisted of organic materials,wax,colloid and asphaltene accounting for over 60%. For wells with more years of production,the plugging materials include both organic and inorganic materials,the major composition of the scales are CaCO_3,CaSO_4,BaSO_4 and SiO. The plugging mostly is centered 3 ~ 5 m around the hole. The plugging formed in water injection wells is the combined effects of ferric salts,ferrites,bacteria,water-sensitive and velocity-sensitive reactions,plugging radium over 5m.For plugging under different well conditions,a plugging-removal system mainly composed of ZJ-UB biologic acid was experimented and developed,able to dissolve wax,scales,reduce surface tension of payzone pores,etc. The field tests show it has good application results.
出处
《钻采工艺》
CAS
北大核心
2016年第5期83-86,105,共4页
Drilling & Production Technology
关键词
低渗透砾岩油藏
堵塞特征
生物酸
解堵技术
low permeability conglomerate reservoir
plugging features
Biological acid
plugging removal technology
