超低浓度多元改性胍胶压裂液在煤层气井中的应用

为解决常规胍胶压裂液破胶后大量残渣对煤层气储层造成严重损害的问题,通过对常规胍胶进行碱化和醚化改性,研制了1种新型多元改性胍胶DX-HPG,并以此为主要处理剂制备了1套适合煤层气储层的超低浓度多元改性胍胶压裂液体系。该压裂液体系具有良好的耐剪切性能、携砂性能和破胶性能,体系破胶液的残渣含量和表面张力均低于常规羟丙基胍胶压裂液,并且其破胶液对煤岩心的渗透率损害率小于13%,远远小于常规羟丙基胍胶压裂液。现场应用结果表明:超低浓度多元改性胍胶压裂液体系的性能达到了现场施工设计的要求,且XS-1井压后产气量明显高于使用常规羟丙基胍胶压裂液的邻井,起到了良好的压裂增产效果。

Application of ultra-low concentration multi-component modified guar gum fracturing fluid in coalbed methane wells

In order to solve the problem of serious damage to coalbed methane reservoir caused by a large amount of residue after gel breaking of conventional guar gum fracturing fluid, a new type of multi-component modified guar gum DX-HPG was developed by alkalization and etherification of conventional guar gum, and a set of ultra-low concentration multi-component modified guar gum fracturing fluid system suitable for coalbed methane reservoir was prepared. The fracturing fluid system has good shear resistance, sand carrying performance and gel breaking performance. The residue content and surface tension of the gel breaking fluid are lower than those of the conventional hydroxypropyl guar gum fracturing fluid, and the permeability damage rate of the gel breaking fluid to coal core is less than 13%, which is far less than that of the conventional hydroxypropyl guar gum fracturing fluid. The field application results show that the performance of ultra-low concentration multi-component modified guar gum fracturing fluid system meets the requirements of field operation design, and the gas production of XS-1 well after fracturing is significantly higher than that of adjacent wells using conventional hydroxypropyl guar gum fracturing fluid, which has played a good fracturing stimulation effect.