Pollution Reduction by Adding Gaseous Fuels in the Diesel Engine

Abstract

With the air pollution problem attracting more and more people's attention the exhaust gas emitted by diesel vehicles occupies a certain proportion of the total pollution sources And the oil crisis is also one of the hot topics nowadays At the same time it has become the most important issue for diesel vehicles to reduce the pollution they emit and the development of alternative fuels In this study four kinds of gases were used to be adding fuel namely hydrogen (H2) imported natural gas (CH4) domestic natural gas (90% CH4 10% CO2) and biogas (70% CH4 30% CO2) as a heavy-duty diesel engine to release total particle matters and other pollutants control technology and to investigate the effect of various gaseous fuels on the total particulate matters and chemical properties of heavy-duty diesel engines after being added at a ratio of 10% and 20% (heating value) respectively The results show that compared to the diesel engine with pure diesel after adding gaseous fuels the reduction rate of total particulate matter is about 42 3% and 58 2% respectively and the reduction effect is similar In the case of polycyclic aromatic hydrocarbons (PAHs) the addition of hydrogen reduces the PAHs mass and toxicity emission by 87 7% to 84 4% and 50 0% to 59 0% respectively Adding imported natural gas will result in increased PAHs toxicity emissions especially when adding 20% of imported natural gas the PAHs toxicity emission will increase 73 8% compared to pure diesel And adding domestic natural gas and biomass gas will reduce the PAHs toxicity emissions The main composition of dioxin exhaust by diesel engine is PCDF In addition adding hydrogen the PCDD/Fs mass emission and toxicity emissions increased by 16 7% to 103% and 32 8% to 104% respectively while the imported natural gas reduced the PCDD/Fs toxicity emissions of by 10 9% to 27 7% and the remaining gaseous fuels did not change significantly It is concluded that after the adding gaseous fuel the reduction effect of hydrogen on TPM and PAHs is the best but the dioxin emissions increase However if the problem of dioxin emission can be solved using hydrogen-blended diesel fuel can be an alternative to energy in the future Although the gaseous fuel equipment costs are higher but the price of gaseous added fuel is low compared to other diesel engine control technology In addition if the adding gaseous fuels is to be widely used in the future the reduction rate of pollutants should be enhanced through the optimization of engine operation and combustion conditions so as to ensure the reduction rate

Date of Award	2018 Jan 31
Original language	English
Supervisor	Yee-Lin Wu (Supervisor)