采油污水反渗透淡化预处理试验研究

Experimental study on the pretreatment technology for reserve osmosis treatment of oilfield wastewater

为了验证"生化—絮凝—双介质过滤—超滤"作为油田采油污水反渗透淡化处理的预处理工艺的可行性,试验考察了处理工艺对降低污水含油量、COD、浊度等指标的效果.试验结果表明:当生化处理停留时间为10 h时,生化出水含油量、COD分别由处理前的30～60 mg/L和314～464mg/L下降到处理后的0.5～2.0 mg/L和86～122 mg/L.生化出水再经絮凝—双介质过滤—超滤工艺处理后,出水含油量小于0.5 mg/L,浊度小于0.2NTU,SDI值小于3.0,达到反渗透进水要求,且生化出水絮凝处理可以改善超滤膜运行状况.

In order to verify the feasibility of 'biological contact oxidation——flocculation-double media filtration-ultra-filtration' as the pretreatment technology for reverse osmosis treatment of oilfield wastewater,the pretreatment result of the treatment technology is investigated by experiments.The experimental results show that,when the biological contact oxidation treatment time is 10 h,the biological contact oxidation treatment can make the oil content and COD of oilfield wastewater reduce to 0.5～2 mg/L and 86～122 mg/L from 30～60 mg/L and 314～464 mg/L.After the wastewater treated by the biological contact oxidation is treated through 'flocculation-double media filtration-ultrafiltration',its average oil content is less than 0.5 mg/L,turbidity is below 0.2 NTU,and SDI is less than 2.0,which can meet the needs of reserve osmosis treatment technology to the quality of inlet water.Therefore,the 'biological contact oxidation-flocculation-double media filtration-ultra-filtration' can be as the pretreatment technology of reverse osmosis treatment of oilfield wastewater.