Transportation fuels bioethanol

The first biodiesel initiatives were reported in 1981 in South Africa and in 1982 in Austria, Germany and New Zealand. Since then, the production of this alternative fuel has seen enormous developments, particularly in Europe, where it reached 5.7 millions tons in 2007. It is expected to increase further to fulfill the recent decision of the European Parliament to substitute 10% of transport fuels with biofuels by 2020. According to assessments of the European Community, to reach this target, the production of bioethanol, biodiesel and second-generation biofuels should reach 36 Mtep (tep = tonnes equivalents petrol) in 2020. 

Today, an international awareness of the increasing C02 concentration in the atmosphere has resulted in the formation of the Kyoto Protocol, which has led many countries to make the commitment to decrease the emission of C02. One way of decreasing C02 emissions could be substitution of fossil fuels with renewable energy sources. The net production of C02 is significantly lower when bioethanol produced from plant materials is used as transportation fuel instead of fossil fuels, since C02 is assimilated... 

Similarly to oil-based refineries, where many energy and chemical products are produced from crude oil, biorefineries will produce many different industrial products from biomass. These will include low-value, high-volume products, such as transportation fuels (e.g. biodiesel, bioethanol), commodity chemicals, as well as materials, and high-value, low-volume products or speciality chemicals, such as cosmetics or nutraceuticals. Energy is the driver for developments in this area, but as biorefineries become more and more sophisticated with time, other products will be developed. In some types of biorefinery, food and feed production may well also be incorporated. 

First generation bioethanol and biodiesel production, which mainly makes use of cereal grains and vegetable oils, represents a growing source of high quantities of protein as a valuable by-product. Sanders et al. (2007) estimated that a 10% substitution of fossil transportation fuels worldwide by first generation biofuels would result in an annual production of 100 million tonnes of protein - about four times the proteins requirement of the world s human population. A direct result of this would be the saturation of traditional protein markets. New opportunities would therefore emerge for chemical production from proteins. 

Bailey, B.K., Performance of ethanol as a transportation fuel, in Handbook on Bioethanol Production and Utilization, Wyman, C.E., Ed., Taylor Francis, Washington, DC, 1996, pp. 37-60. 

Bioethanol produced from pretreatment and microbial fermentation of biomass has great potential to become a sustainable transportation fuel in the near future [1]. Brazil and the United States are the largest producers of ethanol for transport, accounting for about 90% of world production. Both coimtries currently produce about 16 billion liters per year with a displacement of 40% of gasoline use in Brazil but only 3% in the United States with... 

It has been concluded that microalgal biodiesel is the only renewable biodiesel that has the potential to completely displace liquid transport fuels derived from petroleum. Existing demand for liquid transport fuels could be met sustainably with biodiesel from microalgae, but not with bioethanol from sugarcane (17). 

Numerous environmental and social benefits could result from the replacement of petroleum-based transport fuels with bioethanol converted from renewable biomass. 

For example, in a (thermochemical) biorefinery, biomass is converted into energy carriers such as transportation fuels (e.g., ethanol), heat, and power and/or chemicals. In terms of energy content, the amount of biomass for (transportation) fuels and CHP (e.g., by combustion) is much higher than the amount used for the production of chemicals. However, in terms of added value, chemicals can provide a significant contribution to the overall cost effeaiveness of the refinery. When the main product of a biorefinery is (hemi) cellulose bioethanol, the lignin ends up in a residue that mostly is used as a fuel to generate heat. The economics of the biorefinery will benefit much from the valorization of this lignin-rich residue to value-added aromatic chemicals. 

Many variations exist of pyrolysis-based biorefineries, and an early (1920s) example is the production of charcoal and various other products in the continuous wood distillation plant of the Ford Motor Company in Michigan, USA. This plant used 400 tons per day of scrap wood from the automobile body plant.The Ford plant not only produced make acetic acid (among charcoal and other products) but also ethyl acetate (via esterification with bioethanol), which the company required in its lacquer and artificial leather departments. The first T-Fords used bioethanol as their transportation fuel. Figure 8.2 gives a schematic overview of the plant that was completely self-sufficient with regard to its heat demand. 

The need to address the issue of global warming and fossil resource depletion has prompted research on the sustainable production of environmentally benign fuels and chemicals [ 1]. A biorefinery, which utilizes biomass as the starting material for the production of fuels and chemicals, can not only generate sustainable energy but also reduce CO2 emitted by fossil fuel combustion. For instance, bioethanol is one of the most promising alternatives to conventional petroleum-based transport fuels. The United States produced 52.6 billion liters of ethanol fuel in 2011, an increase from 49.2 billion liters in 2010 [2]. 

Because of the high demand of biofuels in the present situation, several biorefineries have been established based on the availability of agriculture and forest products and also in efforts to utilize wastes obtainable from the paper and pulp industry, sugar mills, etc. (Cherubini et al., 2009). This system yields transportation fuels such as biodiesel and bioethanol, platform chemicals, and some chemical intermediates for cosmetics and pharmaceuticals. Since the Phase III biorefineries are the ones that may be expected to serve as an all-in-one source of food, feed, and platform chemicals, the various known forms of Phase 111 biorefineries are discussed in some detail below. 

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