The Research Of Phenolic Resin Wastewter Treatment In Membrane Bioreactor With Polyester Nonwoven Fabrics

Phenolic resin wastewater produced in the production process of phenolic resin contains highly toxic substance such as phenolic compounds,formaldehyde and so on. Through the pretreatment in prophase,biological toxicity and COD, etc greatly reduce,but phenolic resin wastewater still can't reach emission standard. What this topic research is phenolic resin simulation wastewater. With its unique advantages, MBR process has been widely studied and used in the degradation of high concentrations and high toxic organic wastewater.In order to overcome problem of high cost of membrane modules, in this paper, low cost nonwoven polyester material which has superior performance was used as membrane to degrade simulated phenolic resin wastewater to achieve the purpose of water reuse.In this work,the membrane filtration property of polyester nonwoven material and the effect of phenolic resin wastewater treatment in submerged MBR(membrane bioreactor)system was investigated under the same conditions. The results showed that the system of A/O-DMBR with polyester nonwoven fabrics adapted to the impact of high concentrations of organic wastewater well.and had a better treatment for simulated wastewater of phenolic resin. Average removal of total organic carbon(TOC),chemical oxygen demang(COD)and ammonium (NH4+-N) in the effluent were maintained above 95%.The system had a stable operation with low turbldity in effluent under a condintion of membrane flux of 0.4L/h, a mixed liquor suspended solid(MLss) of 1000 mg/L, and aeration intensity of 0.4 m3/h,and in the moment the removal of phenol and formaldehyde is above 99%, which meets the living standard of miscellaneous water.In this experiment,the SEM images showed that the membrane aperture of the polyester nonwoven fabrics was in the range of 20-50μm, the membrane surface of effluent side did not find significant pollution after continuous operation of 60 days,but the surface of contaminated membrane formed a thick filter cake.Via the research of the membrane fouling pollutant,it was discovered that the the membrane fouling of polyester nonwoven fabrics has a significant relationship with extracellular polymeric(EPS). In addition, composition of membrane fouling has a certain correlation with the EPS in the irreversible pollution layer.Further research found that EPS mainly consists of protein and polysaccharide, among which the polysaccharide of EPS in the irreversible fouling layer are more closely associated with pollution.In summary,the research proved that nonwoven polyester had practical value in eng -ineering. As a membrane filter material,it can ensure effluent water quality. Effluent water meet the requirements of water reuse.At the same time, the issue revealed the deep-seated links between the nonwoven MBR membrane fouling and the EPS.