低伤害改性植物胶压裂液体系

Low Damage Modified Vegetable Gum Fracturing Fluid System

在苏里格气田低伤害压裂液的应用越来越受到重视。研制出一种低伤害压裂液体系,该体系以改性植物胶为稠化剂,其是植物胶经过特殊的分子改性并引入了疏水基团,属于阴离子型瓜尔胶,相对分子量小(10万～20万),分散性好,水不溶物含量小于3%,增黏速度快,其适宜加量为0.2%～0.3%,破胶液残渣含量为羟丙基瓜胶的1/3～1/4;采用新型交联剂,并且为双交联体系,交联后形成牢固的十二面体结构。性能评价结果表明,该压裂液体系的携砂性能和耐温耐剪切性能好。在苏76-X井进行了施工试验,压裂后试气分类该井为一类井,地质分类该井为二类井,压裂效果显著。

Low damage fracturing fluid system is applied more and more widely in Sulige gas field.A kind of low damage fracturing fluid system is developed based on novel cross-linking agent forming deltohedron structure,and thickening agent of modified vegetable gum that has some characteristics of modified by hydrophobic groups,cation guar gum,molecular weight of 100,000 to 200,000,good water dispersion ability,content of water insoluble matter not more than 3%,viscosifying fast with concentration of 0.2% to 0.3%,and low content of breaking-gel residue.The application in well Su76-X show that,after fracturing,this well is of the first class in gas production testcategory,and it is of the second class in lithologycategory,which has good fracturing effect.