ОҢТҮСТІК ҚАЗАҚСТАН МЕДИЦИНА АКАДЕМИЯСЫ, ХАБАРШЫ №4(942, 2021 жыл, ТОМ 2
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The main problems associated with the quality car are:
• Low octane rating of gasoline sold mostly ;
• Low production of winter varieties of diesel fuel.
The search for alternative fuels to reduce dependence on petroleum and emission of pollutants into the
atmosphere has stimulated many scientific studies. The goal is to develop fuels that can be used in existing
vehicles without the need for major changes in their engines. A term often used for fuel derived from
renewable sources is 'biofuel', which has strong links with the concept of sustainability, whereby the use of
natural resources to meet current needs should not compromise the needs of future generations. of this
handbook describes different biofuels in detail. All transport fuels can be
classified
in fossil fuels and
renewable fuels. The process chains for all transport fuels are shown in Figure 7. For the production of fossil
and renewable transport fuels different primary energy sources are needed. Although mainly crude oil is used
for the production
of transport fuels today, the figure shows various opportunities for the production of
biofuels. Thereby the utilization of biomass as feedstock source does not necessarily create a different fuel
type than today. For instance, biodiesel is similar to fossil diesel and bioethanol has similar properties as
petrol. This is a great advantage, since existing infrastructure does not have to be intensively modified.
However, there exists a large variety of different
feedstock sources, biofuels, process technologies and
utilizations of biofuels. Thus, PPO and biodiesel (FAME, FAEE) can be produced directly from oil
containing plants. Ethanol can be processed from sugar, starch and cellulose. In addition, biomass can be
liquefied to yield “bio crude” or gasified. A promising application for the future is the utilization of
biomethane for transport.
In contrast, the use of other renewable energies, like electricity from wind or photovoltaic, is more
complicated to use with today’s infrastructure. Hydrogen can be used in very different ways, directly for
vehicle propulsion in a combustion engine or preferably in a fuel cell or indirectly as a component for the
production of other fuels. However, hydrogen requires far-reaching changes in technology and infrastructure.
In particular, energy effective use of hydrogen requires the introduction of fuel
cells instead of internal
combustion engines. This presents another technology and cost challenge. According to the vision report of
the EC, hydrogen from renewables for fuel cell driven vehicles might be a long term option (EC 2006a
p. 20).
Feedstock sources can be divided into animal fats, oil crops, sugar plants,
starchy plants, cellulosic
biomass and wet biomass. During processing theses feedstocks, they can be transformed into liquid and
gaseous biofuels. Another classification of biofuels can be applied to first generation and second generation
biofuels. PPO, biodiesel, ETBE and bioethanol are
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