The Engineeirng Application Study Of Orgianic Wastewater Treatment By BLR Anaerobic Reactor

In this paper we finished the pilot test treating sorbitol production wastewater and a projecttreating leachate from a trash incineration plant with the high-rate anaerobic which wasdesigned and made by ourselves. This kind of anaerobic reactor of which the waterdistribution system, three-phase separator, gas-liquid separator and gas lifting device had beenoptimized, was developed from the third generation anaerobic reactor. We also selected anddesigned the controlling rules for sorbitol production wastewater and leachate based on theirdifferent features. We hope this paper can provide some information for designing, controllingand operating of anaerobic reactor treating sorbitol production wastewater or leachate fromtrash incineration plant.We did a on-site polit test treating sorbitol wastewater in sorbitol plant by a high-rateanaerobic reactor with effective volume of18L. The startup condition of sorbitol wastewatertreatment by high performance anaerobic reactor at mesophilic temperature was indicated inthis study. The results showed that it was practicable to treat sorbitol wastewater by anaerobicreactor at35±1℃. When the volumetric loading rate of reactor kept at15kgCOD/(m3.d), theeffluent COD concentration was between300and350mg/L, the ammonia nitrogenconcentration was lower than10mg/L.0.33m3biogas with the methane concentration of70%to80%(v/v) was obtained from each kilogram of COD degradation. The effluent volatile fattyacid (VFA) concentration was between50and100mg/L and the alkalinity was about2000mg/L, which showed that the anaerobic system was operated well. It also found that theconcentration of SO2-4could influence the degradation of COD. The COD removing ratedeclined from80%to74%when the concentration of SO2-4increased.BLR(Biogas-lift Reactor) anaerobic reactor was used to disposal the leachate fromincineration plant, the inoculated sludge was digested sludge and the temperature kept at33±2℃,the volume loading rate increased from1kgCOD/(m3.d) to10kgCOD/(m3.d) after120days’ operation and it kept stable, the effluent COD concentration was4500~6500mg/L withthe removal rate of88~92%, effluent VFA concentration was200~600mg/L, pH was7.4~7.6,effluent SS concentration was about1g/L, granular sludge could be observed in the reactor.The reactor didn’t acidified in early running phase when VFA/ALK was less than1.6, it couldmaintain steady when VFA/ALK was lower than0.3. The ammonia inhibition effect was notfound in the operation phase when ammonia concentration increased from400mg/L to2200mg/L. The biogas generation was stable with0.32m3/kg COD removal.After the anaerobic pilot test and project study. We designed two control rules for sorbitolwastewater anaerobic system, one of them was simple and easily adjusted which based on themethane content in the biogas, the other one was a fuzzy controlling based on pH and biogasproduction which was able to incorporate experience of human operators when lack ofdetailed experimental data or elaborate reaction mechanism. We designed a multi-dimensionalintelligent expert system controlling the anaerobic reactor treating leachate from trashincineration plant. It would provide operation recommendations or alarm information whenacquired and analyzed the on-line date of biogas production, methane content in biogas, VFA concentration, pH and ALK in effluent. This system could help make timely adjustments,reduce labor costs and most important improve the stability of the system.