还原性铁和硫离子对聚合物性能的影响

Effect of Fe^(2+) and S^(2-) on Performance of Polymer Solution

为了考察大庆油田聚合物溶液黏损的影响因素,对注入井井口的聚合物溶液进行全离子分析,研究还原性Fe^(2+)和S^(2-)离子对聚合物溶液性能的影响。结果表明,在厌氧条件下,Fe^(2+)和S^(2-)浓度对聚合物溶液的性质影响不大。在曝氧条件下,聚合物体系黏度随着Fe^(2+)和S^(2-)浓度增加而急剧下降,含1.18mg/L Fe^(2+)的聚合物溶液和含2.49 mg/L S^(2-)的聚合物溶液的黏度分别下降了42.49%和49.42%;随着:Fe^(2+)和S^(2-)浓度增加,聚合物分子线团尺寸也大幅减小,聚合物溶液的触变性变差。在Fe^(2+)和S^(2-)存在时,Fe^(2+)和S^(2-)使部分水解聚丙烯酰胺降解引起聚合物链断裂,是造成部分水解聚丙烯酰胺溶液黏度下降的主要原因。针对现场实际提出多种工程措施,以降低还原性物质对聚合物溶液的影响,减少聚合物溶液黏损。

In order to study the viscosity reducing effect of the polymer solution in Daqing oilfield,the totally ion analysis of the polymer solution from the wellhead of the injection well was conducted,the effect of reducing substances,Fe^2＋ and S^2-,on the properties of polymer solution was researched.The results showed that the concentration of Fe^2＋ and S^2- ions had little effects on the properties of the polymer solution under anaerobic conditions,while the viscosity of the polymer solution droped sharply with increase of the concentration of Fe^2＋ and S^2- ions under the condition of oxygen exposure.The viscosity of the polymer solution with1.18 mg/L Fe^2＋ions dropped by 42.49%,while the viscosity of the polymer solution with 2.49 mg/L S^2- dropped by 49.42%.With the increase of concentration of Fe^2＋ and S^2-,the polymer molecules line size also sharply reduced,the thixotropy of the polymer solution degraded.Fe^2＋ and S^2- ions made HPAM degradation,which was the main cause of HPAM solution viscosity decreased.In the field,several measurements were proposed in order to reduce the effects of reducing substances on the polymer solution.