Biomass-derived transportation fuels

The European Commission wants to have a contribution of 12% energy from renewable sources to the energy budget within the EC in 2010. The relative amount of bio-fuels will increase to a level of 5.75%, this is more than twice the corresponding use of oil. The US Department of energy has set goals to replace 30% of the liquid petroleum transportation fuels with biofuels and to replace 25% of industrial organic chemicals with biomass-derived chemicals by 2025 [7]. 

Figure 2.13 did not include all the biomass conversion processes discussed above. It only considered those that produce transportation fuels. The processes that convert bio-feedstock into biocrude or electricity could not be included because their products have a different value than the transportation fuels. Such a comparison can be attempted by displaying the total manufacturing cost of biobased products in a graph that shows typical relationships between the price of crude and that its derivatives, i.e., of fuel oil, transportation fuel and electricity. This has been done in Fig. 2.14 for the lignocellulose conversion processes. 

The FTS converts synthesis gas into mostly liquid hydrocarbons [12-15]. Depending on the origin of the synthesis gas, the overall process from carbon feedstock to liquid product is called gas-to-liquids (GTL), coal to liquids (CTL), or biomass to liquids (BTL). The product spectrum, however, is broader than liquid hydrocarbons alone and can include methane and alkanes, C H2 +2 (with n from 1 — 100), alkenes or olefins (C H2 n > 2), and to a lesser extent, oxygenated products such as alcohols. Hence the FTS offers the opportunity to convert gas, coal, or biomass-derived syngas into transportation fuels, such as gasoline, jet fuel, and diesel oil, and chemicals, such as olefins, naphtha, and waxes. The reactions need a catalyst, which in commercial applications is either based on cobalt or iron. 

Fig. 33.11. Comparison of costs for gasoline and various biomass derived fuels for transportation.

ABSTRACT Biomass fast pyrolysis liquid is being developed for fuel and chemical applications, As these developments proceed, the liquid product is increasingly being transported by air, water, rail and road to satisfy user demands for products. This paper addresses the legislative requirements and regulations for the safe transport of this liquid. As biomass derived fast pyrolysis liquid is not on the UN approved carriage lists its own classification has been determined from the UN manual as ... 

Sharma, R.K., and Bakhshi, N.N. Catalytic Upgrading of Biomass-derived Oils to Transportation Fuels and Chemicals. Can. J. Chem. Eng. 69, 1991. 

The current ethanol supply is, in the large part, derived from starch. Nevertheless, vast amounts of agricultural residues and other lignocellulosic biomass can serve as the feedstock for ethanol production. Theoretically, enough ethanol can be produced from cellulosic biomass to meet most of the liquid fuel requirements in the US. The expanded utilization of lignocellulosic biomass for ethanol production can also free starchy crops for food and other uses. In addition, less carbon dioxide emission can be realized if more ethanol can be produced from lignocellulosic biomass and if the market for ethanol as a transportation fuel can be expanded beyond the current level. 

The introduction of biomass-derived components or even substitution fuels may help to alleviate the dependency on oil and to control fossil carbon dioxide emissions from transport, provided some conditions are respected ... 

With ever increasing requirements for clean transportation fuels and liquid hydrocarbon supplies, there is an opportunity to produce significant quantities of synthetic ultra-clean fuels that are essentially sulfur-free. These synthetic fuels can be produced from natural gas, coal, petroleum coke, biomass, and other non-traditional hydrocarbon sources. Most of these products are fungible and compatible with current products and distribution infrastructure and can be produced at costs competitive with conventional crude oil-derived products under certain market conditions. 

The OECD transport sector produced nearly three times as much carbon dioxide in 1990 as it did in 1960 (lEA, 1993). There is a growing concern that these increasing carbon dioxide emissions will create a greenhouse effect on our planet (Boer et al., 1990). One way of reducing the emissions of CO2 would be to introduce renewable fuels, such as alcohol fuels or biogas. Carbon dioxide, which is produced by combustion of biomass-derived fuels, is naturally recycled and consumed in the photosynthesis. This means that there will be no net increase of COj in the atmosphere when using, for example, ethanol produced from biomass. This is valid if biomass-derived fuels or chemicals are used in all parts of the production chain. 

Ethanol is being hailed as the fuel of the future. Interest in the production of fuel ethanol from renewable sources has increased significantly. For fuel ethanol production to become a practical reality, cheaper substrates and more efficient production processes are needed [1,2]. Biomass, which includes all plant and plant-derived material, forms a potential renewable source of sugars that can be fermented to produce fuel ethanol and a variety of other fuels and chemicals. In addition to the many benefits common to renewable energy, biomass is particularly attractive because it is currently the only renewable sustainable energy source for liquid transportation fuel. 

Alternative Fuels - A popular term for "non-conventional" transportation fuels derived from natural gas (propane, compressed natural gas, methanol, etc.) or biomass materials (ethanol, methanol). 

Ethanol derived from biomass, one of the modem forms of biomass energy, has the potential to be a sustainable transportation fuel, as well as a fuel oxygenate that can replace gasohne (14). In particular, ethanol used as a liquid transportation fuel could reduce domestic consumption of fossil fuels, particularly petroleum. 

Vennestr0m et al., 2011). In summary, an upgrading of biomass to higher-value products is a reasonable approach to replace crude oil. For electrical (on-grid) energy production alternative sources are simply conceivable. It is liquid transportation fuels where most problems occur for the judgment if they can or should be replaced by biomass-derived products or not. 

Huber GW, Chheda JN, Barrett CJ, Dumesic JA. Production of liquid alkanes for transportation fuel from biomass-derived carbohydrates. Science 2005 308 1446-50. 

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