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Hydrogen biomass

Biomass may be a low cost renewable source of hydrogen in the near future. It could be a major renewable source of hydrogen. Biomass can be gasified and converted into hydrogen and electric power. The process is similar to coal gasification. [Pg.113]

Forsberg, C. (2008), Meeting US Liquid Transport Fuel Needs with a Nuclear Hydrogen Biomass System , International Journal of Hydrogen Energy (2008), doi 10.1016/j.ijhydene.2008.07.110. [Pg.97]

With all components in the ideal gas state, the standard enthalpy of the process is exothermic by —165 kJ (—39.4 kcal) per mole of methane formed. Biomass can serve as the original source of hydrogen, which then effectively acts as an energy carrier from the biomass to carbon dioxide, to produce substitute (or synthetic) natural gas (SNG) (see Euels, synthetic). [Pg.9]

Steam also is blended with air in some gasification units to promote the overall process via the endothermic steam—carbon reaction to form carbon monoxide and hydrogen. This was common practice at the turn of the nineteenth century, when so-called producer gasifiers were employed to manufacture LHV gas from different types of biomass and wastes. The producer gas from biomass and wastes had heating values around 5.9 MJ /mr at... [Pg.24]

Another hydrogenation process utilizes internally generated hydrogen for hydroconversion in a single-stage, noncatalytic, fluidized-bed reactor (41). Biomass is converted in the reactor, which is operated at about 2.1 kPa, 800°C, and residence times of a few minutes with steam-oxygen injection. About 95% carbon conversion is anticipated to produce a medium heat value (MHV) gas which is subjected to the shift reaction, scmbbing, and methanation to form SNG. The cold gas thermal efficiencies are estimated to be about 60%. [Pg.25]

Direct hydrohquefaction of biomass or wastes can be achieved by direct hydrogenation of wood chips on treatment at 10,132 kPa and 340 to 350°C with water and Raney nickel catalyst (45). The wood is completely converted to an oily Hquid, methane, and other hydrocarbon gases. Batch reaction times of 4 hours give oil yields of about 35 wt % of the feed the oil contains about 12 wt % oxygen and has a heating value of about 37.2 MJ /kg (16,000 Btu/lb). Distillation yields a significant fraction that boils in the same range as diesel fuel and is completely miscible with it. [Pg.26]

An early source of glycols was from hydrogenation of sugars obtained from formaldehyde condensation (18,19). Selectivities to ethylene glycol were low with a number of other glycols and polyols produced. Biomass continues to be evaluated as a feedstock for glycol production (20). [Pg.359]

There is a general understanding of the reasons why nutrients are critical to the productive capacity of biological systems. The dry biomass of plants and animals comprises some 20 elements, the predominant atoms being those of carbon, hydrogen, oxygen, and nitrogen. Moreover, ideally they are required in fairly... [Pg.28]

Hydrogen is the most abundant element in the universe and is found in a variety of compounds, including hydrocarbons (e.g., fossil fuels or biomass) and water. Since free hydrogen does not occur naturally on earth in large quantities, it must be produced from hydrogen-containing compounds. [Pg.653]

If hydrogen is made from decarbonized fossil fuels, fuel-cycle emissions can be cut by up to 80 percent. With renewable energy sources such as biomass, solar, or wind, the fuel cycle greenhouse gas emissions are virtually eliminated. It is possible to envision a future energy system based on hydrogen and fuel cells with little or no emissions of pollutants or greenhouse gases in fuel production, distribution, or use. [Pg.657]

Robert Boyle, an Irish chemist noted for his pioneering experiments on the properties of gases, discovered methanol (CH3OH) in 1661. For many years methanol, known as wood alcohol, was produced by heating hardwoods such as maple, birch, and hickory to high temperatures m the absence of air. The most popular modern method of producing methanol, which IS also the least costly, is from natural gas (methane) by the direct combination of carbon monoxide gas and hydrogen in the presence of a catalyst. Methanol also can be produced more expensively from oil, coal, and biomass. [Pg.794]


See other pages where Hydrogen biomass is mentioned: [Pg.618]    [Pg.177]    [Pg.23]    [Pg.345]    [Pg.279]    [Pg.72]    [Pg.213]    [Pg.618]    [Pg.177]    [Pg.23]    [Pg.345]    [Pg.279]    [Pg.72]    [Pg.213]    [Pg.210]    [Pg.30]    [Pg.9]    [Pg.21]    [Pg.22]    [Pg.24]    [Pg.25]    [Pg.25]    [Pg.27]    [Pg.32]    [Pg.37]    [Pg.426]    [Pg.427]    [Pg.495]    [Pg.238]    [Pg.238]    [Pg.215]    [Pg.2216]    [Pg.126]    [Pg.16]    [Pg.160]    [Pg.652]    [Pg.653]    [Pg.657]    [Pg.659]    [Pg.1052]    [Pg.1114]    [Pg.1181]    [Pg.367]    [Pg.894]    [Pg.290]   
See also in sourсe #XX -- [ Pg.40 , Pg.41 , Pg.42 , Pg.51 ]




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