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In the context of China's urban sewage sludge increased dramatically and the increasing scarcity of energy, anaerobic digestion biogas sewage sludge quickly stabilized and an important resource. However, due to hinder and methanogenic bacteria cell wall sludge demanding requirements of conditions, conventional anaerobic digestion process biogas conversion rate is lower. Therefore, for the above two issues, to carry out hot alkali pretreatment of anaerobic digestion, biological additives enhanced anaerobic methanogenic and optimization of the anaerobic digestion process parameters, such as a series of anaerobic digestion to promote technology research, so as to sludge engineering application of anaerobic digestion technology reserves and theoretical guidance. The main conclusions of the study include: (1) using a combination of single factor and orthogonal experiments investigated sludge thermal alkaline pretreatment process parameters (temperature, pH, reaction time) as well as heat treatment and pH adjustment sludge cells the effect of the dissolution process. The results show that: the sludge soluble chemical oxygen demand (SCOD) and reaction temperature, solution pH, reaction time, a positive correlation, in which the pH of SCOD reaction time has minimal impact on. Sludge the lysis optimal conditions: reaction temperature of 120 ℃, pH = 11, the reaction time was 15min, under this condition, the sludge supernatant SCOD up to 14810 mg / L, and total chemical oxygen demand (TCOD ratio) ratio of 49.29% up to 4560 mg / L, a 27% increase in total nitrogen (TN), total organic carbon (TOC), total suspended solids (TSS) and volatile suspended solids (VSS) removal rates of 22.85% and 40.93%. Supernatant molecular weight distribution (MWD): hot alkaline treatment sludge gt; 1000KDa MW matter content with increasing pH and temperature increase, when pH = 11, the portion of the material from the original sludge 20.94% increased to 31.70%; When the temperature of 120 ° C, the portion of the material up to 49.83%. Hot alkaline pretreated sludge under optimized conditions, anaerobic digestion experiments units VSS 166.23mL/g-VSS sludge accumulated methane production reached the original mud as 130.01 mL / g-VSS 27.86%. Hot alkali treatment the sludge gas production methane content of 68.14%, 64.18% of the the relatively original mud methane content, six days in advance, in order to effectively promote the rate and yield of anaerobic sludge biogas. (2) examined the different microbial activity enhancer: Reduced coenzyme II (NADPH), acetyl coenzyme A (Acetyl Coenzyme A), amino benzoic acid (Para-aminobenzonic), sodium dodecyl sulfate (SDS) and 16 alkyl trimethyl ammonium chloride (1631) the influence of the sludge in the anaerobic biogas process. The study found: II promoting effects of reduced coenzyme most significant 15.90% the methanogenic amount higher than the control. 50mg / L, containing solid rate of 3%, 35 ° C and 300mL of sludge in the reaction system, NADPH dosage anaerobic to promote the best results in the experimental cycle, the cumulative amount of methane production for 127.13mL / g-VSS, compared to controls the 114.40mL/g-VSS, an increase of 11.12%. VSS amount of Methane gas production rate and methane content of sludge units through comprehensive comparison of various anaerobic conditions, SCOD change, pH change and VSS removal rate derived when the initial pH of alkaline (pH = 8.5 ), temperature (55 ℃) and solids ratio of 3%, its unit VSS anaerobic gas effect. (3) Finally, the development of the constant KH kinetic model based on the hydrolysis of the rate-limiting step of anaerobic degradation of the gas production, and solving out the organic matter in the kinetic parameters of the model of the conversion rate and the rate of hydrolysis of the gas production. The actual anaerobic gas production in conjunction with various conditions, fitting gas dynamics model equations, based on the size of the parameters of the model equations to verify the the anaerobic gas effect of various operating conditions. Comprehensive comparison with different amounts of kinetic model: dosage 50mg / L and kh are were 223.978mL/g-VSS, and 0.14218d -1 . The conditions multiple sets of data show that: to characterize the degree of hydrolysis, gas production and use of a hydrolytic kinetic model to approximate the reaction process of anaerobic dynamics rationality and feasibility. Through the sludge each of The Turbine degree of hydrolysis and anaerobic methane yield calculated 203.40mL/g-VSS total gas production 403.64mL/g-VSS.
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