| In this study, multi-surface hollow ball packing and flexible three-dimensionalpacking was added into an Anaerobic Baffled Reactor (ABR) system respectively.Compared with a ABR without packing, the laboratory-scale Hybrid AnaerobicBaffled Reactors (HABRs) fed with containing high strength particulate organicmatter wastewater were designed to investigate the performance of pollution removal.Three reactors had the same structure and size. They all enlarged the firstcompartment to improve the removal effect. This study was mainly divided into threeparts. Firstly, to study the startup of reactors, increased the activity of anaerobicsludge and accomplished the growth of biofilm on the packing. Secondly, study theperformance of reactors when the loading was increased. With the continuousincreasing of the influent COD concentration and particulate organic matterconcentration and the reducing of Hydraulic retention time, the performance ofpollution removal was studied in three reactors. Thirdly, physical characteristics,structure characteristics and biodiversity of anaerobic sludge through the variousstages, especially the granular sludge, was studied to explore the activity of anaerobicsludge in the reactors. The conclusions of this study could be summarized as follows:(1)The experiment started up with low load. When volume loading was0.6kgCOD/(m~3·d) and HRT was30h, after73days, COD removal efficiency weremore than75%and SS removal efficiency reached90%in three reactors. The pH ofeffluent was stable. The experiment started up successfully. Reactors filled withpacking had a batter treatment effect than Reactor without packing. The initialcompartment played significant role in the removal of COD and SS. It demonstratedthat, with the increasing of HRT, the degradation and interception of pollutants was improved by anaerobic microorganism in the bigger compartment1.(2)In the start up stage, biofilm grew well on the packing, especially in reactorwith multi-surface hollow ball packing. Sludge performance was much more batterthan seeding sludge, which was more obvious in compartment1. With Enoughnutrition, anaerobic microorganisms grew, which made the value of VSS/SS increased.There was only a litter fine granular sludge formed in the startup stage.(3)In stable operation stage, organic loading and SS loading were finallyincreased to5.6COD/(m~3·d) and2.24SS/(m~3·d) respectively, by changing theconcentration of influent COD and particulate organic matter gradually. The removalrate of COD and SS were all above93%. It showed that both ABR and HABR had agood treatment effect in treating various concentrations of containing particulateorganic matter wastewater we tested in this experiment. In this stage, reactor withmulti-surface hollow ball packing still had a better treatment effect, while reactorwithout packing was the worst.(4) Along the length of reactor, concentration of COD, SS and VFA decreased ineach compartment, while the pH and alkalinity increased. When the loading was low,most COD and SS were removed in compartment1, which mainly play the role ofhydrolytic acidification. When the HRT reduced from30h to24h, reactor filled withmulti-surface hollow ball packing maintained in good working condition, whilereactors with no packing and flexible three-dimensional packing fluctuated a lot.Organic matter, which could not digested by compartment1in time, was digested bythe following compartments. It made the number of compartment playing the role ofhydrolytic acidification increased.(5) In loading-increasing stage, the sludge activity improved and the partical sizeincreased. Along the length of reactor, sludge activity of each compartment reduced,sludge activity of the first compartment was much better than the other compartments.Since loading progressively decreased down the reactor, big granular sludge firstformed in the initial compartments, and the partical size decreased along the length ofreactor. (6) The result of observation by scanning electron microscopy showed thatmicrobial gradually decreased in each compartment along the length of reactor. Whenthe influent loading was low, bacillus and coccus were predominant bacteria in theinitial compartments, while the number of filamentous bacteria increased in the lastcompartments. Methonasarcina was found in the middle compartments of the reactorin the later stable operation stage, which meant granular sludge was mature.Observing granular sludge by transmission electron microscope showed that therewere a lot of microbial communities in initial compartments and were rich inbiodiversity. In the last compartments, microorganism was scattered and only had afew microbial communities. Biodiversity was researched in each compartment byPCR-DGGE. The results were in agreement with the electron microscope observing. |
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