| Anoxic-anaerobic denitrification and methanogenesis combined bed used anoxic-anaerobic combined bed as segment A of A/O technics,to treat wastewater containing high concentrations of organic matter and nitrogen, which made the nitrification liquid in effluent of segment O back flow to the bottom of the combined bed, which made simultaneous denitrification and methanogenesis come ture.The dynamic experiment of this study was done in anoxic-anaerobic denitrification and methanogenesis combined bed in the conditions of 35±1℃, the anaerobic granular sludge cultured in previous experiment was used as seed sludge, and the landfill leachate which taken from adjusting tank of the sewage treatment station in Taiyuan Hou Village Landfill was used as processing object (Influent COD around 2000-6000mg/L), on the foundation of the previous experiment, to study the treatment effect of landfill leachate in denitrification and methanogenesis combined bed, in the condition that the influent COD load was more than 30gCOD·(L·d)-1; The static experiment which used little bottle as static reactor and the granular sludge taken from the bottom of combined bed as seed sludge was done in a constant temperature chest, the landfill leachate which kept COD concentration around 2000-6000mg/L and NO3-N concentration around 300mg/L breathe into the reactor intermittently. This study investigated the dynamic experiment and combined with the analysis of static experiment and dynamic parameter, resulted as follow: 1. NO3-N load kept unaltered, only COD load increased to 30 gCOD·(L·d)-1-36gCOD·(L·d)-1, denitrification and methanogenesis in the combined bed was destroyed. Recovery COD load to 30gCOD·(L·d)-1 below in time, effects of operation could recover in about a week's time.2. COD load kept unaltered, only N03-N load increased to 2.0g NO3-N·(L·d)-1 above, denitrification and methanogenesis in the combined bed was destroyed, treatment effect reduced. Restored NO3-N load to 1.0 g NO3-N-(L·d)-1, operation effect couldn't restore.3. To denitrification/methanogenesis technics, organic matter content adding was thought to be excessive, so organic matter content couldn't be the limiting factor of denitrifying reaction rate, denitrifying dynamics accorded with the single substrate restricted model.4. COD removal of the main reactor was used to provide denitrification carbon sources in earlier stage, mainly controlled by NO3-N concentration control; in later period mainly used for methanogenesis, mainly controlled by COD concentration. Therefore, COD degradation accorded with the single substrate restricted model, could be analyzed according to the single substrate biodegradation dynamic model.5. Methanogenesis reactions predominantly occured after NO3-N in the reaction bottles were basicly consumped, gas production of reaction bottles mainly provided by methanogenesis reaction of COD removal. The faster the substrate biodegradated, the higher methanogenesis reacted.6. Contrasted substrate biodegradation rate with methanogenesis rate and linear regression, educed a significant correlation between methanogenesis rate and substrate biodegradation rate. The modulus of methane production rate was Y=0.344 mL/mg, the result was close to the theoretical data (0.35mL/mg), this experiment is static reactor denitrification and methanogenesis function of the granular sludge produced by ability and general anaerobic digestion reactor closer, methanogenesis ability of denitrification and methanogenesis granular sludge in the static reactor of the experiment was close togeneral anaerobic digestion reactor.7. The modulus of methane production rate of dynamic reactor was 0.250mL/mg, lower than that in static reactor, it was because of the dynamic reactor continued to keep concentration of nitrate about 400mg/L-800mg/L, this was higher than static reactor which kept concentration of nitrate about 300 mg/L...
|
PDF Full Text Request