Study on advanced treatment of alkali dyeing wastewater by continuous process of iron carbon micro-electrolysis-UASB-SBR

摘要

By use of iron-carbon micro-electrolysis-UASB-SBR continuous process, treatment of an actual alkali dyeing wastewater (pH 11.50-13.50) taken from a certain factory in Xian-Yang was studied. The results indicated that: (1) When the influent COD is 1000-1600 mg-L~(-1), chroma 250 times, firstly effluent COD reduced to 400-800 mg-L~(-1) and chroma 40 times by iron-carbon micro-electrolysis process, secondly effluent COD dropped to 250-500 mg-L~(-1) by UASB process, finally effluent COD dropped to 70-98 mg-L~(-1) by a SBR with loading PVA micro-gel beads, which meet the direct emission limits of water pollutants for dyeing and finishing of textile industry (GB 4287-2012);;(2) Effective combination process of iron-carbon micro-electrolysis with UASB-SBR can be obtained through HRT optimization of micro-electrolysis reaction (HRT=10), that not only meet the requirement influent pH of anaerobic reactor, but also greatly reduce the cost of alkaline in practical application of iron carbon micro-electrolysis.