生物基页岩气压裂用降阻剂的制备与表征

Synthesis and characterization of bio-friction reducer for slickwater fracturing of shale gas reservoirs

采用氧化还原体系,通过反相乳液法,制备了页岩气压裂用黄原胶-丙烯酰胺-2-丙烯酰胺基-2-甲基丙磺酸钠接枝共聚型降阻剂。考察了单体浓度、引发剂用量、反应温度及单体配比对产物接枝率和接枝效率的影响,确定最优条件为:单体质量浓度0.25 kg/L、引发剂质量浓度0.5 g/L、反应温度50℃、单体配比0.3时,接枝率可达490.0%,接枝效率达91.2%,红外、X射线衍射及扫描电镜微观形貌观察证明了接枝共聚反应的发生,在质量分数为0.15%、剪切速率3879 s-1时,降阻剂室内降阻率可达61.7%。

A grafting polymer [XG-g-( AM-co-AMPSNa) ]has been synthesized by inverse emulsion polymerization of xanthan gum( XG),acrylamide( AM),2-acrylamide-2-methylpropanesulfonic acid( AMPS) and sodium hydroxide( Na OH) with a redox initiator. The effects of varying the monomer concentration,initiator content,reaction temperature and monomer feed ratio on the grafting rate and efficiency were investigated,and the optimal conditions were found to be as follows: a monomer concentration of 0. 25 kg / L,an initiator content of 0. 5 g / L,a reaction temperature of 50 ℃ and a monomer feed ratio of 0. 3. Under the optimum conditions,the maximum grafting ratio and efficiency were 490. 0% and 91. 2%,respectively. When used as a friction reducer in slick water fracturing of shale gas reservoirs,the reduction resistance of a solution of [XG-g-( AM-co-AMPSNa) ]with a concentration of 0. 15% reached 61. 7% at a shearing rate of 3879 s- 1.