| Using anaerobic digestion to achieve the reduction of residual sludge, stability, resources, with low energy consumption and sludge good stability, and kill the bacteria produce methane, and other advantages, the technology is widely used in urban sewage plant Sludge Disposal. Because sludge solids Biodegradability of low anaerobic digestion to complete a considerable length of time, even though the 20 to 30 d retention time (SRT) can be removed only part of the sludge volatile solid (VS). Effectively improve the sludge solids biodegradable, and improve the ability of the anaerobic sludge digestion rate and extent of the technology is currently facing a major problem. Because sludge floc and the role of the cell wall barriers exist, intracellular activity of extracellular organic difficulty in the role of the enzyme release and generate effective small molecules, which limits the anaerobic digestion rate and extent. Therefore, the realization of sludge cell decomposition of organic matter and release of intracellular anaerobic digestion is to improve performance, enhance the efficiency of key. The microwave pretreatment issues, resolve the remaining sludge, and to enhance anaerobic digestion performance.Major research: study different microwave energy, residence time, the moisture content of the sludge on the microwave effect of sludge crack the use of the test method uniform design analysis and comparison of various factors on the effects of cracked mud, and to determine the optimal conditions for microwave crack in the optimal design of microwave crack under anaerobic digestion test, the crack of microwave performance of anaerobic digestion (including organics removal, bio-gas production, pathogens and Huichongkun killing rate).The results show that: crack sludge microwave technology can be quickly destroyed sludge and sludge floc cells, intracellular material from the sludge into the water phase, resulting in increased value of aqueous phase SCOD. SCOD added value than with the microwave energy, microwave radiation, as well as the increase of moisture content of the sludge to reduce the increase. Role in the microwave, VS removal curve than with the increase in energy consumption, microwave radiation and the extension of water and reduce the rate of upward trend. The microwave radiation to a certain extent, can promote the reduction of sludge.Microwave break through the uniform design sludge testing, the various factors on the rate of increase of sludge SCOD chronological order: water content> microwave energy than> microwave irradiation time, the removal of sludge VS order: Microwave energy than> microwave irradiation time> moisture. Comprehensive energy consumption and consider the effects of crack, crack sludge effect of microwave optimal conditions were as follows: 97% moisture, microwave energy than 4 W / mL, 180 s microwave irradiation time.Optimal conditions in the microwave crack under the temperature anaerobic digestion experiments, compared with the reference group, a microwave pretreatment sludge after anaerobic digestion can be greatly enhanced anaerobic digestion of organic reactions, and the degradation rate of biogas production. Sludge retention time of 8 days, compared with the reference group, other groups of anaerobic digestion reactor gas production increase: 288%, 434%, 443% and 451%. Microwave break after anaerobic digestion can reduce the anaerobic digestion of sludge retention time. Compared with the reference group, the microwave sludge can be cracked after the anaerobic digestion tank sludge retention time of 20 days from the general shortened to eight days. After microwave break after dealing with the anaerobic digestion reactor from the mud significantly reduce the number of E. coli, sludge retention time of up to 8 d after the break after microwave treatment of anaerobic digestion reactor from the mud in full compliance with E. coli GB GB8172 -87 (farm towns refuse controlstandards) of the sludge farm coliform value> 10-1 to 10-2 requirements.
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