Treatment of the oil extractionwastewater by plate ceramic membranes

Abstract:

To achieve the water standard of low-permeability reinjection for secondary oil wastewater treatment, this experiment took the oil-field wastewater as the processing object, and an experimental device which took plate ceramic membranes as the core processing unit in the production site was set up. The study mainly focused on the effects of the membrane flux, reaction temperature and aeration rate on treatment by monitoring the changes in transmembrane pressure difference. On the premise of normal operation of the experimental device, the optimum membrane, reaction temperature flux and aeration rate was set as 22.5 L／(m²·h), 50 ℃ and 1 L／min, respectively. Filtration performance of membrane could be better recovered after immersing the membrane in 0.05 mol／L HCl or HNO₃ solution for 12 h, and membrane flux recovery rate reached above 96％. As the results show, oil content and SS of effluenttreated by plate ceramic membrane are less than 1 mg／L, and all indexes of injection water are better than the A1 class standards in SY5329—94. It demonstrates that plate ceramic membranes can replace traditional steps in the oily wastewater treatment, such as flotation, rough filtration and fine filtration.