低渗透油藏回注污水的深度处理中试研究

Pilot-plant of oily wastewater treatment for reinjection of low permeability oilfield

为达到将油田采出水回注低渗透油藏的水质要求,在辽河油田进行含油污水处理试验:先在油田来水进入沉降罐前加入除油剂,使水中油的含量从20g/L降至约0.15g/L,悬浮物含量从10g/L降至3g/L左右;再采用气液多相泵气浮技术净水,使水中油的含量降至约0.005g/L,悬浮物含量降至约0.03g/L;进行初级过滤后,采用硅藻土动态膜超滤工艺精密过滤,最终使水中油和悬浮物含量均小于0.002g/L,悬浮物粒径控制在1μm左右。硅藻土动态膜超滤工艺集中了填充床过滤技术易再生和超滤膜过滤技术高水质的优点,运行费用低,应用前景很好。

In order to meet the strict water quality standards, a pilot plant examination of oil wastewater treatment for reinjection to low permeability oil field was carried out in Liaohe Oilfield. Oil remover was added to the wastewater before it went into the precipitation tank. Then, the oil content of oily wastewater dropped from 20g/L to 150mg/L, as well as the suspended solid from 10g/L to 3g/L. EDUR multiphase pump air floatation was applied, which could reduce the contents of oil and suspend solid to 5mg/L and 30mg/L, respectively. Finally, after a novel technology of guhr dynamic membrane ultra filtration, the content of oil and suspended solid in oily wastewater was all lower than 2mg/L, and the average diameter of suspended solid was about 1μm. Guhr filter that has a low operational cost is in possession of the merits of both packed bed and ultra filtration membrane.