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* Rotary Rig Counts * Renewable Energy o Biofuels o Geothermal o Hydroelectric o Ocean, Tidal & Wave o Solar o Wind * Non-Renewable Energy o Coal o Nuclear o Oil & Natural Gas o Oil & Tar Sands o Oil Shale Researchers Develop Two-Stage Process For Optimal Biohydrogen Production Thursday, 17 July 2008 00:13:00 CDT Alternative-Energy-News.INFO - BioFuel News Researchers have combined the efforts of two kinds of bacteria to produce hydrogen in a bioreactor, with the product from one providing food for the other. According to an article [*.pdf] in the August issue of Microbiology Today , this technology has an added bonus: leftover enzymes can be used to scavenge precious metals from spent automotive catalysts to help make fuel cells that convert hydrogen into energy. Hydrogen has three times more potential energy by weight than petrol, making it the highest energy-content fuel available. Research into using bacteria to produce hydrogen from waste biomass has been revived thanks to the rising profile of energy issues. According to the researchers, the UK throws away a third of its food, wasting 7 million tonnes a year. The majority of this is currently sent to landfill where it produces gases like methane, which is a greenhouse gas 25 times more potent than carbon dioxide. Following some major advances in the technology used to make biohydrogen, this waste can now be turned into valuable energy. Two-stage process There are special and yet prevalent circumstances under which micro-organisms have no better way of gaining energy than to release hydrogen into their environment. Microbes such as heterotrophs, cyanobacteria, microalgae and purple bacteria all produce biohydrogen in different ways, says Dr Mark Redwood from the University of Birmingham. When there is no oxygen, fermentative bacteria use carbohydrates like sugar to produce hydrogen and

Patent number: 5658681 Filing date: Sep 27, 1995 Issue date: Aug 19, 1997 Abstract A fuel cell power generation system including a reforming reactor for reacting a fuel with water to produce a hydrogen-rich reformed gas including carbon monoxide; a CO shift reactor for carrying out a CO shift reaction to decrease the concentration of carbon monoxide in the reformed gas;... About this patent

hydrogen

CO-shift The processes described above produce gas with a high content of carbon monoxide - CO. It is therefore necessary to put the gas through the CO-shift process to increase the content of hydrogen. The shift reaction (see sidebar) is a two-step process to achieve the most complete reaction between CO and steam. Initially steam is added in a high-temperature step (300-500ºC), followed by a a low-temperature step (200ºC), with different catalysts in the two steps. Separation of CO2 Each of the processes described above produces CO2 in addition to H2. To separate hydrogen and CO2, it is common to use amine based absorption processes. This is conventional technology. Methods based on selective membranes or sorbents are under development.

arbon Dioxide Removal Print Page Fossil fuels are the primary sources of carbon dioxide emissions to the atmosphere. Much of the anticipated worldwide effort to reduce carbon dioxide emissions will focus on large point sources such as power plants and petroleum refineries. To contribute to this effort, RTI is actively engaged in a research and development project to develop a new process for removing carbon dioxide from industrial gas streams. RTI's process uses a solid, regenerable, sodium-based adsorbent to remove carbon dioxide from flue gases that fuel power plants. The regeneration of this sorbent produces a gas stream containing only carbon dioxide and water. Condensation separates the water out, leaving a pure carbon dioxide stream that can be used or sequestered. One of the relevant reactions based upon the use of sodium bicarbonate as the sorbent precursor is as follows: 2NaHCO3(s) Na2CO3(s) + CO2(g) + H2O(g) RTI has developed a 2-reactor system for removing the carbon dioxide. Both the adsorption of carbon dioxide and regeneration of the sorbent take place at low temperature (under 150°C). Laboratory experiments at RTI have demonstrated multiple cycles of the adsorption and regeneration phases. In addition, we have developed process information on * Effect of operating conditions * Effect of other feed stream components * Reaction kinetics * Heat and material balances from proc

Economical CO2, SOx, and NOx capture from fossil-fuel utilization with combined renewable hydrogen production and large-scale carbon sequestration Danny Daya, Corresponding Author Contact Information, E-mail The Corresponding Author, Robert J. Evansb, James W. Leec and Don Reicoskyd aEprida, Inc., 6300 Powers Ferry Road, Suite 307, Atlanta, GA 30339, USA bNational Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, USA cOak Ridge National Laboratory, 4500N, A16, MS-6194, Oak Ridge, TN 37831, USA dUSDA-Agricultural Research Service, 803 Iowa Avenue, Morris, MN 56267, USA Available online 17 November 2004. Purchase the full-text article References and further reading may be available for this article. To view references and further reading you must purchase this article. Abstract The objective of this project was to investigate and demonstrate production methods at a continuous, bench-scale level and generate sufficient material for an initial evaluation of a potentially profitable method of producing bioenergy and sequestering carbon. The novel process uses agricultural, forestry, and waste biomass to produce hydrogen using pyrolysis and reforming technologies conducted in a 50 kg/h pilot demonstration. The test runs produced a novel, nitrogen-enriched, slow-release, carbon-sequestering fertilizer. Seven kilograms of the material were produced for further plant growth response testing. A pyrolysis temperature profile was discovered that results in a carbon char with an affinity for capturing CO2 through gas phase reaction with mixed nitrogen-carrying nutrient compounds within the pore structures of the carbon char. A bench-scale project demonstrated a continuous process fluidized-bed agglomerating process. The total amount of CO2 sequestration was managed by controlling particle discharge rates based on density. The patent-pending process is particularly applicable to fossil-fuel power plants as it also removes SOx and NOx, does not require ene

Biohydrogen (gasification) Besides production of biohydrogen from biogas, it can also be produced through gasification of biomass, similar to the production of bio-SNG, which was discussed above. A gasification method has to be used that produces a gas w

thailandia , brazil , wood gas

Producing fuel alcohol via hydrolysis of lignocellulosic biomass leaves a considerable amount of residues waiting for treatment. A study was carried out on the preparation of hydrogen via catalytic gasification of residues from biomass hydrolysis with a novel Ni/modified dolomite binary catalyst, which was prepared by a two-step coprecipitation method and proved available for hydrogen production in terms of both activity and strength. The effects of four operation parameters, that is, the fluidized bed temperature, the catalytic fixed bed temperature, the particle size of the catalyst, and S/B (i.e., the mass ratio of steam to biomass material fed into the fluidized bed per unit time), on hydrogen yield were investigated. The results indicate that hydrogen yield increases with an increase in the temperature of either the fluidized bed or the downstream catalytic fixed bed or the S/B ratio or a reduction in the particle size of the catalyst. The optimum range for each of the four operation parameters from a comprehensive consideration is as follows: 800-850 °C for both the fluidized bed temperature and the catalytic fixed bed temperature, 1.5-2 for the S/B ratio, and 2.0-3.0 mm for the particle size of the catalyst. Furthermore, the gas product from catalytic gasification of residues from biomass hydrolysis contains less CO and CO2 and has a higher H2/CO ratio compared with that of the sawdust. The hydrogen yield of the former is also much higher than that of the latter. These suggest that residues from biomass hydrolysis are an even better gasification material than the original sawdust. This paper provides a novel effective method for modifying the calcined dolomite, which endows the catalyst with satisfactory strength while retaining high activity, and opens a new promising way for utilizing the residues from biomass hydrolysis. Download the full text: PDF | HTML

PDF] A Hybrid Gas Cleaning Process for Production of Ultraclean Syngas Formato do arquivo: PDF/Adobe Acrobat - Ver em HTML However, because activated carbon and molecular sieve. absorbents must be used at ambient .... desirable for our proposed syngas cleaning process. ... www.osti.gov/energycitations/servlets/purl/837307-eWgBqG/native/837307.pdf - Páginas Semelhantes

An improved process is provided for the removal of sulfur oxides from gas or vapor media containing oxygen and water by contacting said media with a catalytically-active carbonaceous char. The improvement is provided by the use of a catalytically-active carbonaceous char prepared by low-temperature carbonization and oxidation of a bituminous coal or bituminous coal-like material followed by exposure to a nitrogen-containing compound during the initial high-temperature exposure of the low-temperature oxidized char. Following this initial high-temperature treatment the material can be further calcined or activated as desired.

"ome University of Colorado students are working to reduce air pollution and put money back into the pockets of drivers in India with kits that turn gas-powered auto-rickshaws into hybrid vehicl"