Need for
Energy
India is growing economically, and it is heavily
dependent on petroleum imports. It has been hit very badly due to the recent
surge in crude prices and uncertainty over future supplies on account of
proposed American sanctions on Iranian crude.
Coal
Liquefication
There are various ways to tackle such problems like
Methane use, CTL techonoly etc. Coal
liquefication, also called Coal to Liquid (CTL) technology is an alternative
route to produce diesel and gasoline and makes economic sense only
in a world of high crude oil prices.
Fischer –
Tropsch Method
CTL was through the Fischer-Tropsch Method that was
implemented in Nazi Germany in the 1940s to meet much of the country’s demand
for diesel during World War II, when oil supplies were limited. CTL
technologies have steadily improved since the war. Technical development has
resulted in a variety of systems capable of handling a wide array of coal
types.
Global
Scenario
South Africa has been producing liquid fuels from coal
since 1955, using the indirect conversion process. The South African company
Sasol has three CTL plants that together produce more than 160, 000 barrels of
liquid fuel per day from coal, which provides for about 30 per cent of South
Africa’s transport fuel requirements.
Despite the high, up-front capital investment costs,
interest in CTL is now growing worldwide, especially in coal-rich countries.
Geographically, most active projects and recently commissioned
operations are located in Asia, mainly in China. This is driven by the
low cost and large reserves of coal in many of these countries.
Benefits of
Technology
Increasing oil prices are increasing fiscal deficit. The
high demand for energy independence and security in energy fields is needed. The
potential for co-development of carbon capture and storage (CCS) technology
will reduce greenhouse gas emissions,
which is again needed.
The Process
It involves gasification of coal, which in turn will produce
synthetic gas (a mix of CO+H2). The synthetic gas can be liquefied to its
fuel equivalent in presence of cobalt/iron-based catalysts at higher pressure
and temperature. However, liquefied coal emits twice as much CO2 as burning
oil. It also emits a large volume of SO2. There is however, a solution to this
today.
One of the benefits of CTL is that the CO2 emissions are
more readily and cheaply captured from CTL plants than from conventional
coal-fired power stations. The captured CO2 can be transported and injected
into underground storage reservoirs (a procedure known as “carbon capture and
storage”—CCS—or “geosequestration”). Without CCS, the carbon footprint of CTL
is at least 150–175 per cent higher than that of conventional petrol/diesel
production from oil.
The International Energy Agency Coal Industry Advisory
Board
The International Energy Agency Coal Industry Advisory
Board supports development of CTL plants with CCS. With
sequestration, powering a car with liquid coal is approximately 30 per cent
cleaner than using petrol. Another benefit of CTL technology is that the
engines of cars need no modification to use the liquid fuel.
The Opinion
of Critics
Critics argue that because of the high costs involved,
and the environmental implications, CTL processes would only be used in the
long term, where there is substantial government support for strategic reasons,
and also where the extra CO2 produced can be effectively sequestered. There are
approximately 30 large-scale CTL plants under construction or in the final
planning stages around the world.
According to a US study, CTL commercialisation is likely
to remain limited to niche markets in coal-producing states offering regional
incentives or strategic markets such as the military with specific fuel and
security requirements.
Conclusion
India has significant coal reserves. CTL plants could be
an alternative source of liquid fuels in India. Based on R&D activities
undertaken for the development of liquid fuels from coal, the CSIR-CIMFR has
successfully installed and commissioned an integrated pilot plant. The pilot
plant produces 5L per day liquid hydro carbon and the institute is seeking
partnership in scaling up the developed technology and commercialising it.
