Immobilized Hydrogen-producing Sludge Degradation Of High Concentration Organic Wastewater Hydrogen Research

It is a trend of world development of energy for development of clean energy and replaceable new energy in the future,which hydrogen energy is the best choice.The method of obtaining hydrogen energy effectively by using microorganisms is one of the important ways.The first choice is the fermentation hydrogen production which has the advantages in high capacity,better stability,rational using of organics in the biological hydrogen production methods.There are two kinds of microbial hydrogen production methods which are suspended bacteria hydrogen production and immobilized microorganism hydrogen production in biological hydrogen production by microbial growth mode.Currently the domestic study is main in suspension bacteria hydrogen production and less in immobilized microorganism hydrogen production.Using hydrogen-producing microorganism embed in sodium alginate gel to deal with the high concentration simulated organic wastewater product hydrogen. Base on our research harvest previously,the different pretreatment methods for immobilizing sludge were compared in this study.The research work includes that how to enhance mass transfer performance of calcium alginate immobilized microorganism cell, and which influencing factors is main effect factor to produce hydrogen by immobilized microorganism,and a key influencing factor was also studied to the semi-continuous operation technology base on above-mentionedThe results of three pretreatment methods that acid treatment,alkali treatment and heat treatment of sludge for fermentation hydrogen production by immobilized microorganism showed that the immobilized microorganisms has higher capacity and accumulated hydrogen production rate in hydrogen production because heat treatment process can be effective against methane-producing bacteria.The different modified materials,such as CA(sodium alginate)/AC(Activated Carbon),CA/CaCO3,CA/Al2O3,were used to modify sodium alginate embed sludge for immobilized microorganism in order to enhance mass transfer performance,and capability of hydrogen production.The results showed that modification of abovementioned methods is effective,and the modified immobilized microorganism used CA/AC has the most quantity of hydrogen production which is 564.59ml and the highest rate of hydrogen production which is 40.35ml/h.The delay time of hydrogen production which used by modified immobilized microorganism by CA/AC is only 11.36 h,which has better application prospects.In the process of producing hydrogen by immobilized microbial anaerobic fermentation,the temperature and pH of fermentation system are the very important effect factors in bio-hydrogen production by anaerobic fermentation.The results showed that the cumulative quantity of hydrogen production reached maximal,496mL at 3.5℃of solution temperature,and the average of hydrogen producing rate is 15.8mLH₂/h·g(sugar),the cumulative quantity of hydrogen production reached maximal,460mL at the initial pH=8.0 of solution,and the average of hydrogen producing rate 14.36mLH₂/h·g(sugar).The best pH of sustained hydrogen production is 4.5～5.5.A suitable range of substrate concentration is needed by the process of hydrogen production by bacterial fermentation.Along with the increasing the concentration of substrate,the cumulative quantity of hydrogen production has been increased.But the delay time of hydrogen production increases significantly.The average rate of hydrogen production by microorganism fermentation becomes lower in the high concentration of substrate.When dosage of sludge is 50 ml,the time of anaerobic fermentation can be shortened and the hydrogen producing rate can be increased.Reactor start-up time and HRT are the key factors in a process of continuous hydrogen production.Experiments showed that the delay time of hydrogen production by immobilized microorganism has been shorten significantly using the method for fixing sludge domesticated different times.Fixed sludge after domesticated eight hours can improve to produce hydrogen rate and short the cycle of hydrogen production.The capacity of hydrogen production increases significantly by activating immobilized microorganism.Hydrogen production by immobilized microorganism has higher cumulative quantity and hydrogen producing rate under the condition of HRT for 2h,and the capability of hydrogen production by immobilized microorganism become better.All the result will provides some reference for producing hydrogen by immobilized microorganism continuously and industrializing producing hydrogen by immobilized microorganism.