阳离子聚合物对聚合物驱污水中HPAM的去除作用及机理

Function and Mechanism of Cationic Polymer for HPAM Removal in Produced Water of Polymer Flooding

研究了阳离子高分子聚合物对污水中HPAM的去除作用,并用扫描电镜和透射电镜研究了阳离子聚合物对HPAM存在形态的影响。研究发现,阳离子高分子聚合物对HPAM有去除作用,其中CJSG阳离子聚合物效果最优。室内与现场试验表明,气浮条件下,CJSG(3mg/L)可使河南油田下二门区块聚合物驱污水中HPAM去除率高于64%,其处理水经混凝沉降后透光率近90%。电镜分析表明,在水中HPAM和CJSG具有不同的存在形态,且与水的矿化度无关;HPAM在水中呈线性链束(团)形态,CJSG则呈串珠(颗粒)形态;两者(HPAM/CJSG)在水中混合均呈串珠(颗粒状)形态。添加CJSG使HPAM流体力学尺寸和溶液粘度下降,HPAM去除率增高。CJSG去除HPAM的机理为:CJSG改变了HPAM在水中的存在形态,降低了其流体力学尺寸、增粘性和溶解性,有利于气浮去除。

HPAM removal of cationic macro-polymer in produced water was studied,effect of cationic polymer on HPAM shape in produced water was investigated by means of scanning electron microscope(SEM) and transmission electron microscope(TEM).The research found cationic macro-polymer could remove HPAM,and the effect of CJSG-cationic polymer was the best.Laboratory and oilfield experiments show 3mg/L CJSG can achieve over 64% of HPAM removal ratio in polymer flooding produced water in Xiaermen Area of Henan Oilfield,and light penetrating ratio of water treated by floc-settling technique can achieve approximately 90%.The electron microscopic analysis indicates HPAM and CJSG in water exist in different shapes,and the shapes are independent of water saliferous quantity.HPAM exists in line-type chain(sheaf) shape,and CJSG has a string beads(granule) shape,but admixture of HPAM and CJSG exist in a string beads(granule).HPAM hydrodynamics dimension and HPAM solution viscosity reduce by adding CJSG,and HPAM removal ratio in water goes up.The mechanism of CJSG removing HPAM is that CJSG changes the shape of HPAM in water,decreases hydrodynamics dimension of HPAM and the solution viscosity as well as its dissolving ability,and enhances HPAM removal ratio in air-floatation.