By: Dr. Ripudaman Singh (Special Correspondent ICN Group) & Hemant Kumar ( Agriculture Correspondent ICN Group)
NEW DELHI: Electricity is the only zero-emission option now available for vehicles, although emissions in the generation of electricity at the power plant are unavoidable. The issue of blending of ethanol with petrol in the country has been under examination for more than two decades.
All the reports had confirmed the technical viability of blending ethanol with petrol for use lowering harmful engine emissions and reducing environmental pollutions the Supreme Court had made a beginning for clean environment by enforcing utilization of Compressed Natural Gas (CNG) instead of petrol in public transport in Delhi, with effect from April, 2001.
At present, ethanol is mainly produced from sugar molasses. The Indian sugar industries have an installed capacity to produce 300 billion liters of ethanol. This quantity is enough to meet the 4% blend with petrol. However, as ethanol can be produced from wide range of raw materials that has either cellulose or starch or sugar, there is ample scope for increasing the production of ethanol and increasing the production of ethanol and increasing the blend to 10%. When there is an assured demand for ethanol can be stepped up using sugarcane juice on Brazilian model. Ethanol blend is eco-friendly and has proved to be safe as motor blend when compared to CNG.
In India oil consumption has been increasing very rapidly with almost stagnant indigenous production of around 33m mt only. More than 67% of countries oil needs are being met through imports resulting in a major portion of its limited foreign earnings getting diverted on oil imports.
Environmental Damage
Apart from the problem of last depleting resources and irreplaceable nature of petroleum fuels, nature of environmental pollution caused by their combustion in automotive and stationary engines. Motor vehicles discharge carbon monoxide, hydro carbons and nitrogen oxides in addition to huge quantities of particulate matter, sulphur dioxide etc. they account for 86% carbon monoxide and 96% of hydro carbon pollution in the city.
Ethanol Source
In India ethanol is mainly produced from molasses, a by product of sugar industry. India is one of the largest producers of sugar in the world and produces 1.8 billion liters of ethanol from its 278 and odd distilleries having an installed capacity of 300 billion liters. Cassava, another very good raw material for ethanol production grows widely in south India and Khandsari molasses can be tapped for production of additional quantities if required in large quantities for use as fuel.
Ethanol’s use as fuel may be regarded as a direct method of obtaining energy. As long as the sun shines, plants will perform their synthesis of starch from the abundant carbon dioxide and water that bathe our planet. From this annually reserved store of raw materials, ethanol can be readily produced. It is a renewal source of energy.
Antiknock characteristics
The principle interest in ethanol as fuel lies in its use as blends with gasoline. It has high antiknock quality and its blends permit higher compression ratio increase with increase of ethanol percentage in the blend.
Engine Emissions
The addition of ethanol to gasoline decrease the carbon monoxide and hydrocarbons in the exhaust effluent, for a given air-fuel ratio. Changing to ethanol blends without mixture adjustments results in less carbon monoxide from the engine exhaust by more addition of ethanol to gasoline. Ethanol addition upto 20% removed even traces of carbon monoxide in the exhaust gas, at the best power ratio for gasoline, when under similar condition of operation would result in about 3% carbon monoxide in the untreated exhaust effluent. Addition of ethanol also reduces exhaust hydrocarbons by substantial amount. Ethanol is an environmentally friendly oxygenate that helps gasoline bum completely. It also displays benzene found in conventional gasoline, which reduces emissions of carcinogens as well.
Safety and Cleanliness
Ethanol is safer than gasoline due to its higher flash point. Its vapors are not half as heavy as that of gasoline, so that it does not flow and accumulate in dangerous quantities at low levels. It has higher proportion to form as explosive mixture with air. Hence, the fuel is less likely to catch fire in case of accidents. It tends to produce less carbon deposit than normal gasoline and the deposits are softer and easier to remove.
Vehicle application
Use of ethanol in heavy vehicles powered by compression ignition engine is beneficial since it reduces the vehicular exhaust smoke density. It improves thermal efficiency as well as the air utilization factor. By including ethanol as bi-fuel engine deposits are reduced and there is no increase of wear of the engine components. Fumigation of ethanol in heavy duty vehicles powered by compression ignition can increase their power rating by 20% to 50% depending on the engine design. This has added attraction for road transport engines in that it reduces engine noise level and smoke density by 30-50%.
Conclusions
- Ethanol can provide a low knock fuel, with power to withstand high compression ratio and give reduced exhaust emissions.
- Capable of being produced within the country from a wide range of raw materials. This “Home grown” fuel provides satisfactory motor spirit at minimum cost in imported low knock fuels.
- The vital advantage in ethanol’s use is that we will be able to grow our own fuel, in our own country. Research investigations reveal that the country has potentials to produce as high as 300 billion liters of ethanol through sugarcane. Millions of farmers who produce sugarcane and other agriculture produces will stand to benefit.
