Preparation Of Fe/C Composite Material And Its Micro-Electrolysis Combined With Membrane Bioreactor For Dyeing Wastewater Treatment

With the continuous development of the textile industry, China has become the textile factory of world, but the dyeing wastewater coming from the productive process is one of the main sources of water pollution in China, which brings harmful effect on the environment and human. The domestic and foreign researchers pay attention to the treatment of dyeing wastewater. As an environmental friendly technology for wastewater treatment, membrane bioreactor (MBR) which integrates the traits of membrane filtration and microbe degradation exhibits incomparable advantages.This experiment investigated the technique which combines new micro-electrolysis and membrane bioreactor to treat the actual dyeing wastewater. Firstly, we prepared Fe/C composite materials using roasting method, and we also investigated optimum synthesis conditions of activated carbon from the aspects of iron carbon mass ratio (Fe/C), roasting temperature and roasting time. The results showed that the proper operating conditions of activated carbon was under Fe/C of 1:3, roasting temperature of 400℃, roasting time of 80 min, under which activated carbon the treatment of methylene blue using activated carbon solution was best.Secondly, compared with traditional carbon and iron system, Fe/C composite materials could receive a higher effect in new micro-electrolysis treating dyeing wastewater. We also investigated the effect of operating parameters on the degradation reaction, such as pH, hydraulic retention times (HRT), and aeration rate, on the degradation reaction. The results indicated that Optimal operating parameters was pH of 3.5, HRT of 35min, aeration of 6 m3/(m3.min).Finally, we analyzed the effect of treating MBR wastewater, membrane permeability and morphology and structure of microbial in bioreactor compared with adding pretreatment of new micro-electrolysis.After a long time running, the results indicated that Iron/modified activated carbon micro-electrolysis-MBR system showed a higher removal of COD of 94.8% and chromaticity of 91.0% in degrading dyeing wastewater comparing with traditional MBR. In membrane permeability, pretreatment of new micro-electrolysis enhanced flux of MBR, and final the flux maintained a value of 18.8 L/m3hbar which was about 5.3 times of Traditional submerged MBR. We found a large amount of zoogloea and organics on membrane surface using Scanning electron microscopy, but the flux could recover to above 93% after chemical cleaning.In addition, we also investigated the effect of on the morphology and structure of microbial new micro-electrolysis. The results shows that the effluent of micro-electrolysis could enhance sludge sedimentation properties and biological flocculation, enlarge Sludge particle size when the effluent of micro-electrolysis entered MBR system. Thus, it could reduce membrane fouling of cake layer.