| Epoxy resin waste;water is a high-concentration organic salt-containing industrial wastewater.Its composition is complex,and it is difficult to effectively treat it by conventional treatment processes.In this paper,the combined iron-carbon micro-electrolysis-Fenton oxidation technology was used to pretreat the wastewater from the production of epoxy resin,and then UASB-SBR were used for biological treatment.At the same time,the two strains of halophilic bacteria screened were made into a composite bacterial agent at a certain ratio and added to the SBR reactor for biological enhancement treatment.In this dissertation,the main influencing factors of iron carbon micro-electrolysis-Fenton oxidation pretreatment of epoxy resin wastewater were investigated,and the process parameters were optimized.The results demonstrate that the optimal process conditions for iron-carbon micro-electrolysis were:iron-carbon volume ratio is 1:1,the initial pH of the wastewater was 2.0,and the reaction time was 120 min.At this time,the CODCr removal rate was 2.1%,and the Fe2+ concentration in the effluent was 7.24 mmol·L-1,which could meet tho demand of Fe2+ in the subsequent Fenton oxidation method.The optimal process conditions of the Fenton oxidation method were:Fe2+concentration was 7.24 mmol·L-1,pH value was 3.0,H2O2 was added in four doses,and the total amount was 190 mmol·L-1,at room,temperature.After 60 minutes of reaction,the CODCr removal rate was 69.3%.The removal rate of CODCr by iron carbon micro-electrolysis-Fenton oxidation pretreatment could reach about 75%,the effluent CODCr was about 2200 mg·L-1,and the B/C of wastewater was increased from 0.21 to 0,43,which significantly improved the biochemical performance of wastewater and reduce the load for subsequent biological treatment.Mud samples from the water wells of the second settling pond of epoxy resin production enterprises were collected,and two strains of haloph ilic bacteria HO2 and HO3 were obtained through enrichment,domestication screening,separation and purification,According to the bacterial morphology analysis,physiological and biochemical characterization and 16S rDNA gene sequencing results in NCBI database,HO2 was a Corynebacterium sp.;and H03 was a Shewanella sp.Optimal growth conditions for HO2 and HO3 were:temperature 35? and 30?,sh aker speed 120 r·min-1,pH 7.0?8.0.In addition,both strains can grow normally in the NaCl concentration range of 10 to 80 g·L-1 and 10 to 60 g·L-1,respectively,indicating that they can adapt to changes in salinity.UASB combined with SBR was used as a biological treatment process to further treat the pretreated effluent,and the effects of different salinity and hydraulic residence time(HRT)were studied.When the chloride ion concentration was 25 g·L-1,the CODCr concentration of the pretreated effluent was 2200 mg·L-1,the pH of the inlet water was adjusted to neutral,the removal rate of CODCr was about 57%when HRT was 48 h.The SBR reactor was used to further process the UASB effluent,and the CODCr removal rate was 49.6%.The culture solution of two strains of halophilic bacteria HO2 and HO3 were made into a bactericide in a volume ratio of 1:2.When the dosage was 12%,the removal rate of organic matter in the epoxy resin production wastewater could reach 80.8%,and the CODCr concentration of the final effluent was about 198 mg·L-1,which can meet the takeover standard of the industrial park sewage treatment plant. |
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