Kinetic Study Of The Anaerobic Fermentation Of Activated Sludge Wastewater Hydrogen Production

With the development of the world economy, demand for energy grows day by day in every country. However, that non-renewable fossil fuel energy is close to depletion. If new alternative sources of energy cannot be found, it will be a strait for our human beings to tide over the energy crisis. Hydrogen as a new type of clean energy, because of its high heat of combustion value, small size, completely pollution-free, and other characteristics, becomes the best alternative energy sources. Moreover, besides the use of fuel combustion, hydrogen can also be used for fuel cell manufacture and provide electrical energy, and be used as chemical raw materials and so on. Therefore, the development of hydrogen energy determined to win.After investigating the research status at home and abroad and the results of preliminary studies of our team in this field, this study used activated sludge as a hydrogen-producing strains of anaerobic fermentation and used simulating sucrose waste water as the substrate, studied the main ecological factors on the anaerobic fermentation of hydrogen production of intermittent operation conditions, as well as the dynamics under this conditions. Preliminary study of hydrogen production in continuous flow operating conditions has also be done.The study of the main ecological factors on the anaerobic fermentation of hydrogen production of intermittent operation conditions shows the result that, at the conditions of this study, when the initial substrate concentration is 6g-sugar/L, initial pH in the vicinity of 8.0, the fermentation temperature is 35±1℃, the best effect of hydrogen production can be obtained. The largest relative hydrogen production capacity is 139.65 ml-H2/g-sucrose.According to the study of dynamics on the anaerobic fermentation of hydrogen production of intermittent operation conditions,3 models had been obtained: microorganism growth model, hydrogen production model and substrate consumption model. The rate of hydrogen production model in this study has been revised to improve its fit the measured data. From the kinetics model analysis, hydrogen is mainly a product of growth-related type. In theory, the growth of micro-organisms for the delay was 7.828h, the largest growth concentration and rate of micro-organisms were 1.640g/L,0.2344g/(L ·h). The delayed time of hydrogen production was 9.156h in theory, the largest hydrogen production capacity was 6981mL, the largest hydrogen production rate was 845.7mL/h.According to the study of control conditions about hydrogen production through anaerobic fermentation and dynamics under batch operation condition, raise temperature to 36±1℃. Research on the basis of the fermentation time and stay on the fermentation of hydrogen production after the impact of the best basis for the fermentation time was 15h, the best residence time was 6h, fiting the result of dynamics analysis. In this study, the maximum rate of hydrogen production is 809.4 mL/h, close to the calculated data of the modle. The maximum relative rate of hydrogen production up to 3.24L-H2/(L-reactor·d), or 3.24L-H2/(g-sugar·d). The largest hydrogen content up to 58.48 percent, the reactor could run for more than 10 days.