中国石油大学学报（自然科学版）2018，Vol.42Issue(4)：100-110,11.DOI:10.3969/j.issn.1673-5005.2018.04.012
胍胶降解菌对地层压裂液伤害的修复机制
Remediation mechanism of guar degrading bacteria on hydraulic fracturing fluid damage
摘要
Abstract
Aiming at the pollution and damage of the fracturing fluid on the reservoir in low-permeability or tight reservoir, the mechanism of using microbial method to remediate the formation damage caused by guar gum fracturing fluid was studied. Guar gum degrading strains were isolated and screened by dilution-plate method using guar gum as sole carbon source.Then the bacterial strain was identified through the colony morphology, physiological-biochemical tests and 16S rDNA sequence a-nalysis.And the effect of bacterial degradation on the guar gum fracturing fluid was investigated by the apparent viscosity, av-erage molecular weight change, as well as the degradation of fracturing fluid residueand particle size..In addition, the effec-tiveness of microbial remediation was researched through the artificial sand pack.It is found that 7 bacterial strains are isola-ted and one strain of them is screened for the follow-up tests, which is identified as Bacillus paralicheniformis (CGS).After using this bacterial strain to degrade the guar-based fracturing fluid, the apparent viscosity decreases from 117 mPa· s to 3.3 mPa· s with the degradation rate of 97.00%and the average molecular weight reduces from 119062 to 28089.CO2and N2O are produced in the biodegradation and the active substrate can be synthesized by CGS to degrade the guar gum.And the in-soluble residue of guar gum changes from 81.67 mg to 51.67 mg with the reduction rate of 36.73%.The particle size of the insoluble residue decreases from 78.598 μm to 59.905 μm with the reduction rate of 23.78%.The original permeability of sand packs are 108.70×10-3and 16.90×10-3μm2, respectively, and the permeability decreases to 5.18×10-3and 7.93× 10-3μm2due to the fracturing fluid damage.However, the permeability can be recovered to 92.58×10-3and 16.32×10-3 μm2with recovery rates of 85.17%and 96.57%after the microbial remediation.关键词
水力压裂/胍胶/细菌/地层伤害Key words
hydraulic fracturing/guar gum/bacteria/formation damage分类
能源科技引用本文复制引用
马鑫,雷光伦,王志惠,达祺安,张鑫,宋萍,姚传进..胍胶降解菌对地层压裂液伤害的修复机制[J].中国石油大学学报（自然科学版）,2018,42(4):100-110,11.基金项目
国家自然科学基金项目(51604291) （51604291）
山东省自然科学基金项目(ZR2016EEB05, ZR2017MEE074) （ZR2016EEB05, ZR2017MEE074）
青岛市源头创新计划应用基础研究项目(17-1-1-34-jch) （17-1-1-34-jch）
中央高校基本科研业务费专项(17CX02010A) （17CX02010A）
中国石油大学(华东)研究生创新工程项目(YCX2017023) （华东）
