一种环保型无泡防水锁剂

An Environmentally Friendly Non-foaming Anti-water Blocking Agent

为提高钻井液用防水锁剂的抑泡和环保性能,以海藻酸、羟乙基乙二胺(AEEA)、环氧氯丙烷(ECH)和季戊四醇(PETP)为原料,合成了一种天然改性产物作为防水锁剂SMFS-1。借助傅里叶红外光谱(FT-IR)仪进行了分子结构表征。防水锁性能测试结果显示,加入SMFS-1后水溶液的表面张力能够降低至25 mN/m以内,减小岩心自吸水体积,可促使岩石表面由亲水向中性转变,提高岩心渗透率恢复值至80%以上。SMFS-1抗温可达120℃,吸附性能优异,无起泡效应,对钻井液的流变性和滤失性能影响小。环保性能测试结果显示,SMFS-1的半致死浓度(EC50)为32250 mg/L,生物降解性评价指标(Y)为17.36,达到排放标准,易被生物降解。

In order to improve the bubble inhibition and environmental protection performance of the waterproof locking agent for drilling fluid,a natural modified product SMFS-1 was synthesized from alginic acid,2-(2-aminoethylamino)ethanol(AEEA),epichlorohydrin(ECH)and pentaerythritol(PETP)as raw materials.The molecular structure was characterized by Fourier infrared spectrometer(FT-IR).The test results of waterproof lock performance show that the surface tension of aqueous solution can be reduced to less than 25 mN/m after the addition of SMFS-1,which can reduce the volume of core self-absorption,promote the change of rock surface from hydrophilic to neutral,and increase the recovery value of core permeability to more than 80%.SMFS-1 is resistant to temperature up to 120℃,has excellent adsorption performance,no bubbling effect,and has little impact on rheological properties and filtration properties of drilling fluid.The environmental performance test results showed that the semi-lethal concentration(EC50)of SMFS-1 was 32,250 mg/L,and the biodegradability evaluation index(Y)was 17.36,which met the emission standard and was easy to biodegrade.