The year 2074 will have been hydrogen society by the magic number of hydrogen. Biohydrogen will contribute to the hydrogen society, because we should produce the hydrogen from renewable energy as solar power, wind and biomass. The development of BioHydrogen from 2 stages system, H2 fermentor and CH4 fermentor, is progressing well with the midget plant study using the non-edible biomass, which is expected to be commercialized in the near future.
Methane fermentation is an attractive process to recovery energy as biogas from various kinds of biomass. In this process, hydrogen can be also recovered prior to methane production, named as hydrogen-methane two-step fermentation process. Biological hydrogen has some advantages to apply to fuel cells such as no contamination of CO and less hydrogen sulfide. In this article, after microbial and process aspects of methane fermentation were explained, why hydrogen can produced during methane fermentation was described. Then, our attempt for development of the process to treat organic waste discharged from bread manufacturing factory was also introduced.
Aomori prefecture, in which Hirosaki University is located, has a low average annual number of hours of sunshine (1541.9 h in 2011) and a large amount of agricultural residues such as apple pomace, pruned branches from apple trees, and rice straw that consist of various sugars. Therefore, we selected a fermentation process for biological H2 production. Apple pomace is one of the major agricultural residues in Aomori, and it would be useful to develop an effective application for it. In this article, we report that the insoluble material from apple pomace stimulated H2 production by a newly isolated Clostridium beijerinckii strain, HU-1. HU-1 produced H2 with a production rate of 14.5 mmol of H2/L/h in a fed-batch culture at 37°C, pH 6.0, and we determined that HU-1 was one of the highest H2-producing strains in Clostridia. When HU-1 was cultivated in a culture containing the insoluble material from apple pomace, HU-1 produced H2 at a rate approximately 1.2-fold greater than that observed without the addition of the insoluble material from apple pomace.
The development of a sustainable, new energy source that replaces energy that uses the dryness type resources such as oil and coal is hoped for. It should be a method easily accepted to the negative environmental impact decrease type such an energy source and the society. It is expected as clean energy for the citizens to accept sunlight, the force of the wind, and natural energy for can the reproduction of the biomass etc. it easily now. We paid attention to the biomass. In such a current state, sunlight, the force of the wind, and the natural energy such as biomasses are expected as clean energy that accepts easily for the citizens. The biomass is unused wood, excrement of the living thing, an abolition plant, garbage, and an organic wastewater etc. These most is materials abandoned in the past. The source of the biomass energy is solar energy originally taken by the plant. And, it is a carbon neutral. Then, this studying aimed at the efficiency gain of the method of producing the hydrogen gases by using an organic wastewater that was a kind of the biomass. The hydrogen gases are produced with an organic wastewater by the action of sunlight and phototropic bacteria, and it is possible to use it as a hydrogen source of the fuel cell. The hydrogen production efficiency at the practical use level is not achieved though real large-scale experiment for the hydrogen production by the phototroph such as algae has been conducted after it enters the 21st century. That is, the cost performance for practical use is not obtained. We proposed the method for the efficiency gain by using the sunlight wave length conversion material (net) and the aluminum foil light reflection material and did an experimental examination. As a result, the design parameter of the system to produce hydrogen with the wastewater by photosynthesis by using the purple non-sulfur microorganism was decided. A new finding was able to be obtained simultaneously with this about the effectiveness of the method of the proposal for the photosynthesis efficiency improvement. The highest hydrogen production rate was able to be obtained at 0.08mg/100kcells*day of the amount of substrate (The sugar manufacture wastewater: Molases) . Moreover, the improvement of the hydrogen production efficiency of about 15% was obtained in the maximum with a light wave length conversion net. The design parameter of the biomass hydrogen energy production system when the sugar manufacture wastewater was assumed to be a substrate from the above-mentioned result was decided. And, basic data concerning effective use for the wavelength conversion net was able to be obtained.
Photosynthesis bacteria convert light energy into hydrogen. The mechanism of the photo-hydrogen conversion is described. A high efficiency of ca. 7% was achieved. Combination with anaerobic bacteria enables much efficient conversion from carbohydrates as vegetable wastes, bagasse, municipal wastes etc. For utilization of biomass to electricity, hydrogen is an appropriate material to storage the energy.
Charge separation, in the first process of photosynthesis, could be used for solar cells. The potential of the application of photosynthetic proteins and hydrogenase taken from the bacteria is discussed.
Photobiological production of H2 by cyanobacteria and eukaryotic microalgae that use water as the electron donor has the potential to produc e renewable clean energy on a scale sufficient to meet much of the world energy demand. We are proposing large large-scale photobiological H2 production by mariculture mariculture-raised cyanobacteria where the microbes capture part of the huge amount of solar energy receiv ed on Earth’s surface. The H2 production system is based on photosynthetic and nitrogenase activities of cyanobacteria, using uptake hydrogenase mutants that can accumulate H2 for extended periods even in the presence of evolved O2. This review summarizes photobiological H2 production by microalgae (i.e. cyanobacteria and green algae) and our efforts to improve the rate of H2 production by cyanobacteria through genetic engineering. The challenges yet to be overcome to further increase the conversion efficie ncy of solar energy to H2 also are discussed.
Suitable substrates for dark fermentative hydrogen production include food industry waste and carbohydrate-rich crops. The aim of this report is to show the effectiveness of the membraneless bioelectrochemical system using three electrodes on construction of hydrogen fermentation from the artificial garbage slurry. The potential on the working electrode was regulated to -1.0 V or -0.9 V (versus Ag/AgCl) to avoid water electrolysis with a carbon electrode in the pHout range 5.5-6.4. Hydrogen production reached 2445±815 mL/L/day, and productions of methane and lactate were negligible. In this system, setting the potential on the working electrode through the operation was the operation necessary for stable hydrogen production under relatively acidic pH condition. Methane production from the fermentation end products was possible.
Higher plants, algae and cyanobacteria use oxygenic photosynthesis to convert sunlight energy into chemical energy. Especially, oxygenic photosynthesis uses water as the electron donor. By using molecular device based on the oxygenic photosynthesis organ, epoch-making hydrogen production and photovoltaic conversion system that water can be used as an electron media. In this paper, biohydrogen production and photochemical biofuel cell based on the molecular device using photosynthesis organ chloroplast or photosynthesis protein from Spinach are introduced.
The United Nation Framework Convention on Climate Change: UNFCCC said “Climate change is a complex problem, which, although environmental in nature, has consequences for all spheres of existence on our planet. It either impacts on- or is impacted by- global issues, including poverty, economic development, population growth, sustainable development and resource management.” For the correspondence of the climate change, the Intergovernmental Panel on Climate Change: IPCC provides the basics of scientific knowledge. This article explains the current status and trend of the UNFCCC and the IPCC.