CONTROL OF EXHAUST EMISSIONS OF LOW GRADE LOW HEAT REJECTION DIESEL ENGINE WITH COTTONSEED OIL BLENDED WITH BUTANOL

Abstract

In the context of depletion of fossil fuels, search for alternative fuels has become necessary. Alcohols and vegetable oils are important substitutes for diesel fuel as they are renewable in nature. Neat vegetable oils produce high particulate emissions in diesel engine as they contain fatty acids. Neat alcohol causes combustion problems as it has low cetane number and low energy content. Hence they call for low heat rejection (LHR) engine, which can give high heat release rate and burn low calorific value fuel. They are many methods to induct alcohol in diesel engine out of which blending of alcohol with vegetable oil is simple technique. Butanol has higher calorific value than ethanol and methanol. Hence use of butanol is finding favor in diesel engine. Exhaust emissions from diesel engine once they inhaled cause heat hazards and also environmental impact. Hence control of these emissions is an important and urgent task. Investigations were carried out to determine exhaust emissions of particulate emissions and oxides of nitrogen (NOx) from a low grade low heat rejection (LHR) diesel engine or LHR–1 engine consisting of ceramic coated cylinder head with crude cottonseed oil blended with butanol with varied injector opening pressure. Conventional engine (CE) showed drastic increase of particulate emissions, while LHR engine showed reduction of particulate emissions with crude vegetable oil, in comparison with neat diesel operation on conventional engine (CE). CEshowed reduction of NOx levels while LHR engine showed drastic increase of NOx emissions with crude vegetable oil, in comparison with neat diesel operation on CE. However, exhaust emissions reduced drastically with crude vegetable oil blended with butanol with both versions of the engine.