钻井液用纳米复合乳液成膜剂NCJ-1的合成与评价

Synthesize and evaluation of nano-composite emulsion film-forming agent NCJ-1 for drilling fluid

关键词:  纳米  钻井液  成膜剂  合成  评价

Key words:  nanometer  drilling fluid  film-forming agent  synthesize  evaluation

摘要:

根据纳米复合乳液成膜的作用机理要求,以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、丙烯酰胺(AM)、丙烯酸(AA)和苯乙烯(St)为有机结构单体,以改性纳米SiO2为无机结构单体,利用超声波细乳化原理和水溶性自由基聚合的方法合成了纳米复合乳液成膜剂NCJ-1。以纳米复合乳液成膜剂在原浆中的降失水性能为评价标准,确定出了合成反应的条件:乳化剂用量为0.02mol,反应单体总浓度为10%(w),改性纳米SiO2用量为2%(w),细乳化超声为20min/400W,反应温度为60℃。结果 表明,添加10%NCJ-1的乳液在岩心表面能形成效率为58.2%的半透膜,体系在220℃下热滚16h后,粘度和切力变化较小,流变性稳定,其HTHP(200℃)滤失量仅为27mL,降滤失效果显著。

Abstract:

According to the request of action mechanism of nano-composite emulsion film formation,taking 2-acrylamide-2-methylpropane sulfonic acid(AMPS),acrylamide(AM),acrylic acid(AA),styrene(St) as organic texture monomers and modified nano-SiO 2 as inorganic texture monomers,a nano-composite emulsion film-forming agent NCJ-1was successfully synthesized by the principle of ultrasonic mini-emulsion and the method of water-soluble free radical polymerization reaction.Taking filtration rate of drilling fluid which contains film-forming as the evaluation criterion,the best polymerization conditions are optimized : the emulsor dosage is 0.02 mol,the mass concentration of total monomer concentration is 10%,modified nano-SiO 2 is 2%,ultrasonic time is 20mins under the power of 400W,reaction temperature is 60 ℃.The result shows that it can form a semi-permeable diaphragm on the surface of the core by adding 10% of NCJ-1,the membrane efficiency is 58.2%.The viscosity and shearing force showed little change,and rheology of drilling fluid system keeps stable after heated at 220℃,lasted for 16hours.The fluid system has remarkable fluid loss effect,and the HTHP filtration rate is only 27mL.