摘要
塔里木盆地库车坳陷山前构造带高密度钻井液漏失非常严重,其性质都属于人为压裂诱导裂缝性漏失,不存在砂、泥岩渗透性漏失;过去采用桥接堵漏技术堵漏成功率低的主要原因是配方中缺少大的架桥颗粒,堵漏材料浓度不够所致。该地区发生井漏特点:漏失最浅在井深2150 m处的上第三系,最深在白垩系的井深6862．m 处;满失地层岩性主要为膏岩层上部的泥岩、膏泥岩、泥膏岩和盐膏层下部的粉砂岩及细砂岩;75％的漏失发生在钻进过程中,开始漏速为2 m3/h左右,继而增大到10 m3左右,漏失量多数在20 m3以上;由于压破泥岩类地层而造成的裂缝漏失,漏速一般在20 m3以上直到有进无出,总漏量多为50 m3甚至上百立方米。由实验研究得知,高密度钻井液在低渗透性砂岩和泥岩地层不会发生渗漏,若发生漏失,都是压成小缝漏失,在砂岩、砂泥岩地层发生较小漏失时,采用小颗粒堵漏剂或降滤失剂随钻堵漏的办法是堵不住的。通过室内实验,结合库车坳陷山前构造带高密度钻井液现场堵漏成功与失败的经验教训,研究出了一套适合不同地层不同漏速的高密度桥接堵漏配方。在却勒101、群6井堵漏和提高地层承压能力挤堵,施工5次,一次成功率为100％。MTC浆使用温度分别为95℃和110℃,稠化时间为240-300 min,养护48 h后抗压达5-10 MPa。
Considering the fact that the squeezed liquid of the west WBM after the regular solidification method can not meet the environment protection requirements particular the COD value, the technique of solidification after degradation. Two degradation agents-SW-A and SW-B and one solidification agent have been developed and a series of formulations of combination of degradation agents and solidification a-gent were figured out by the research work. SW A is adapted to waste WBM of high density (>2 g/cm3) and the dosage is about 60 kg/t and SW-B to WBM of density lower than 1. 50 g/cm3 and the dosage is 40 kg/t. By using this technique, the contents of the liquid squeezed after solidification meet the first class state standard for the discarding waste water GB 8978-1996 as if the mechanic strength of the solidification product is higher than 0. 5 MPa.
出处
《钻井液与完井液》
CAS
北大核心
2006年第1期76-77,共2页
Drilling Fluid & Completion Fluid
关键词
井漏
高密度钻井液
堵漏浆
桥堵
MTC技术
Waste water base drilling fluid
Solidification treatment
Degradation
Environment protec tionFirst author's address: PetroChina Tarim Oilfield Branch Company, Kuerle, Xinjiang
