The Process Optimization Of Anaerobic Fermentative Hydrogen Production And Reactor Design

With the development of society and technology, the problem of environmentalpollution and energy crisis caused by the large-scale use of fossil fuels is becomingmore serious so the world focus on the development of clean, renewable energy.Hydrogen is considered to be the best fossil fuel alternative energy for itsadvantages of high energy density, clean and pollutionless, and the high thermalconversion efficiency. Biohydrogen production is a new method for hydrogenproduction that converts the water or organic energy to hydrogen by hydrogenproducing bacteria. Compared with the traditional methods of hydrogen production,bio-fermentation hydrogen production is considered to be a new hydrogenproduction technology with its high stability and environmentally friendlyadvantages.The main factors affecting anaerobic fermentative hydrogen production(including pre-heated treatment temperature and duration of anaerobic activatedsludge, initial pH of the fermentation broth, the concentration of ammonium sulfate,ferrous sulfate and magnesium sulfate) were studied by single factor experiments,and the optimal operating conditions of fermentative hydrogen production wereobtained by orthogonal experiments.The study results showed that initial pH was the most significant facter onanaerobic fermentation hydrogen production, and the optimal hydrogen productionoperating conditions were: pre-heat treatment temperature80°C, pre-heat treatmentduration40min, initial pH8.0, ammonium sulfate3.0g/L, ferrous sulfate0.10g/Land magnesium sulfate0.03g/L. With the optimal conditions, the best hydrogenproduction volumn was630mL and the maximum hydrogen yield was1.92mol-H2/mol-glucose.The SiC structured packings were applied in an up-flow packed bio-reactor tofix microbial by the character of rough surface and high porosity. In the continuousbiohydrogen fermentation experiments, startup time of SiC structured packingup-flow was short, and the reactor could adapt to the change of external conditionsand operated stable. With the initial pH about8.0, the best hydrogen production was0.42L-H2/g-COD. The reactor kept a stable hyodrogen production level of (4.8±0.2)L-H2/(L2d) with COD loading rate of72g-COD/(L2d).