Performance And Functional Bacteria Community Characteristics Of A New Anaerobic Reactor Treating Papermaking Wastewater

Internal Circulation（IC）Anaerobic Reactor, with large rising velocity, efficient mudmixture, stable performance and resistance to shock loading ability and other characteristics,is being used widely to treat pulp and paper industry wastewater with high content ofsuspended solid particles and strong toxicity. Hence there is important significance in theresearch of IC anaerobic reactor optimization and anaerobic granular sludge.But the traditional IC reactor, with high difficulty in making and maintenance, is limitedto popularize in the treatment of pulp and paper industry wastewater. Therefore this subjectbased on a new anaerobic reactor discussed the treatment efficiency and anaerobic functionalflora distribution in start-up procedure by OCC wastewater, of reactor impacted by OCCwastewater VLR fluctuation, in procedure of degrading papermaking black liquid. And itprovided theory and practical foundation in further optimization of reactor in the future and itspractical popularization in papermaking effluent degradation. It was found that:After the start-up was success, compared with the seed sludge, the abundance ofSyntrophomonas spp. increased by30.76%, Acetobacterium species E. limosum increased by52.63%, and Methanomicrobiales increased by276%, in traditional IC reactor(R1). And theabundance of Syntrophomonas spp. increased by33.74%, Acetobacterium species E. limosumincreased by116%, and Methanomicrobiales increased by267%, in the new anaerobicreactor(R2). Although R2cost a long period to be started up, it reduced the difficulty ofmachining and maintenance greatly by reducing the effective height. And R2can match R1interms of treatment efficiency.R1and R2fed by OCC effluent was handled with increasing VLR, from3,6to12kgCOD/(m3d). After45days, the abundance of Syntrophomonas spp. attained(15.00±0.18)%, Acetobacterium species E. limosum attained (7.65±0.19)%,Methanomicrobiales attained (15.71±0.50)%, the SMA was139.99mLCH4/(d g) and CODremoval rate was47.70%, in R1. The abundance of Syntrophomonas spp. attained(20.76±0.51)%,38.40%more than that of R1, Acetobacterium species E. limosum attained(15.55±0.12)%,103%more than that of R1, Methanomicrobiales attained (60.05±0.53)%,282%more than that of R1, the SMA was237.26mLCH4/(d g),69.48%more than that of R1 and COD removal rate was87.20%,82.81%more than that of R1, in R2. It was demonstratedthat the new anaerobic reactor was effectively capable of the VLR fluctuation, and theanaerobic sludge granulation has more activity in R2.The new lab-scale anaerobic reactor fed by black liquid acid precipitation wastewaterwas operated with increasing VLR, under25℃. Eventually InCOD was8700mg/L. The CODremoval rate was49.46%. The Hydraulic Retention Time was37.38h. The VLR was5.59kgCOD/(m3d) and the SMA was355.36mLCH4/(d g). Compared with the seed sludge, theabundance of Syntrophomonas spp. increased by50.87%, Acetobacterium species E. limosumincreased by214%, Methanomicrobiales increased by26.39%, after71days. It wasdemonstrated that the anaerobic sludge granulation was significant in the new anaerobicreactor and such wastewater with high concentration and toxic like black liquid can be treatedeffectively by using the new anaerobic reactor.