弱碱三元复合驱油井结垢影响因素的研究

Study on influential factors of carbonate scale in alkalescent alkaline / surfactant / polymer( ASP) flooding

研究了弱碱三元复合驱油井水结垢的主要影响因素和基本规律,并通过挂片试验考察了不同钢材的结垢差异。结果表明：碳酸盐垢是主要结垢类型,其成垢率受温度、CO_2浓度、矿化度等因素的影响较大。当反应6 h时,在25,45,65℃的成垢率分别为40.07%,57.12%,87%;密闭系统、敞口系统、鼓泡系统6 h结垢率分别为27%,57.12%,85%。矿化度试验结果表明：在5 g/L时成垢率达到最高值82.12%。同时,油管材质会影响模拟结垢水中碳酸钙的结垢,在6~24 h内,各材质加速模拟结垢水中钙结垢由大到小的顺序依次为铸铁、321不锈钢、P110钢、N80钢、45#碳钢。实际生产中应使用平滑的管材,可通过镀膜、涂层等方式对管材进行处理。

The main influential factors and basic rules of the carbonate scale in the alkalescent alkaline / surfactant / polymer（ ASP） flooding wells are studied. The formation of the scale with different material of steel is investigated. The results show that the major scale type is carbonate scale,whose scale formation rate is affected by temperature,the concentration of CO_2,salinity and other factors. When the reaction time is 6 h,the scale rate is 40. 07%,57. 12% and 87% at 25 ℃,45 ℃ and 65 ℃,respectively; the scaling rate respectively is 27%,57. 12% and 85% in closed system,exposure system and bubbling system. The mineralization test results show that the scale rate reaches the highest value of 82. 12% when the salinity is 5 g / L. At the same time,steel tube will affect the formation of calcium carbonate scale in simulation scale solution. The tube materials accelerate the formation of calcium carbonate scale within 6 h to 24 h from high to low is cast iron,321 stainless steel,P110 steel,N80 steel,and 45#carbon steel. Smooth materials should be used in practical production and the materials can be treated by coating film and paintcoat.