Experimental Study On The Pretreatment Of High Concentration Aniline And PASA Wastewater Using On Emulsion Liquid Membrane

High strength Aniline PASA-containning wastewater is mainly produced in dyestuff industry,due to its large scale and complex components, it is one of the severer contamination.Their high concentrations will inhibit the microbial growth, so this waste water is difficult to deal with and its treatment cost is high.Emulsion liquid membrane is a new technology of efficiency, low-cost and no secondary pollution,in recent years was widely used in environmental protection.In this paper, emulsion liquid membrane pretreatment of the high concentration Aniline and PASA simulated wastewater was studied. Firstly the main components of liquid membrane system were determined, then eight main factors including the surfactant dosage, liquid paraffin dosage, membrane inward concentration, the ratio between the volume of oil phase and the sulfuric acid, emulsion-water ratio, the external phase pH value and reaction time were studied by single factors anlysis. Their effect on the stability of emulsion liquid membrane, aniline and PASA removal efficiency were also analysed, according to orthogonal experiments results, the optimal operating conditions was determined.The most efficient removing Aniline conditions were as follows, surfactant mass ratio was 3%, the inner membrane phase was H2SO4 solution with of 2%, paraffin mass ratio was 11%, the ratio between the volume of oil phase and the sulfuric acid 1:1, emulsion-water volume ratio was 1:10, pH value was 10 and the reaction time was 20 minutes.The most efficient removing ammonia nitrogen conditions were as follows: surfactant mass ratio was 2%, the inner membrane phase was NaOH solution with of 10% mass concentration, paraffin mass ratio was 11%, the ratio between the volume of oil phase and the sulfuric acid was in 2:1, emulsion-water ratio volume was 1:5, pH value was 3 and the reaction time was 20 minutes.On these conditions, the removing aniline test was first carried out, the removing PASA experiment was followed, the simulated wastewater and dyestuff was treated by emulsion liquid membrane technology respectively.The results indicated this technology was efficient and had reproducibility, simulated wastewater test results were as follows, the aniline removing rates was more than 97%, PASA removing efficiency was also above 95%, the remaining aniline concentration was less than 35mg / L, the remaining PASA concentration was less than 150mg / L . these achieved the aim of experiment design, also this pretreatment would do good to subsequent biological treatment process.