Study On Treament Of Dyeing Wastewater By Using Conbination Process Of Anaerobic Hydrolysis Acidification And BSBR

According to the characteristics of dyeing wastewater-high concentration of organism, high pH,heaved color and poor biodegradability,an anaerobic hydrolysis acidification is used as a pre-treatment technique to reduce pH,accommodate the quality and quantity of water, and enhance the ratio of BOD₅ and COD_cr,which is propitious to the aerobic bio-treatment latter.Furthermore,the effects of temperature,HRT and the oganic loading to the process are studied to confirm the parameters of the anaerobic hydrolysis acidification in treating dyeing wastewater.The parameters are as foltowing:T=25℃,pH(7.0～8.0),HRT=8h,the volume loading=3.0 kg COD_cr/(m³Â·d)～3.5 kg COD_cr/(m³Â·d),the sludge loading=0.3 kg COD_cr /(kgMLSS.d)～0.35 kg COD_cr/(kgMLSS·d).A BSBR(Bio-Membrane Sequencing Batch Reactor) is used to treat the effluent of anaerobic hydrolysis acidification as a latter treatment technique,and most of COD_cr,BOD₅ and NH₃-N of dyeing wastewater are mainly treated by it.What is more,the way of aeration, the time of aeration,the organic loading are investigated particularly and their parameters are as following:T=25℃,pH=8.0,the time of nonrestrictive aeration=6h,the time of precipitation =1h,the volume loading=0.75kgCOD_cr/(m³Â·d)～4.5 kgCOD_cr/(m³Â·d),the sludge loading=0.10kgCOD_cr/(kgMLSS·d)～0.50 kgCOD_cr/(kgMLSS·d).By experimentation research,it approves that the combination process of hydrolysis acidification and BSBR is compatible in the treatment of dyeing wastewater with high concentration,heaved chromaticity,high PH,and poor biodegradability,The removal rates of COD_cr,BOD₅,NH₃-N and chromaticity are up to 92.06%,94.85%,89.93%and 85.18% respectively,and the final effluent COD_cr,BOD₅,NH₃-N reach Gradeâ… of Discharged Standard of Water Pollutants for Dyeing-Printing of Textile Industry(GB4287-92),the chromaticity also meets the criteria of Gradeâ…¡of Discharged Standard for wastewater of Dyeing-Printing of Textile Industry(GB4287-92).Therefore,the method is effective and feasible in the treatment of dyeing wastewater.Based on the comprehensive analysis of a number of testing data,the mathmatical models of hydrolysis acidification and BSBR have been obtained,which have enriched the theories of treatment of dyeing wastewater and provide some references for further testing, engineering application.It will be also a guidance to other similar industrial sewages.