Charalampos Arapatsakos

Environmental pollution from the use of alternative fuels in a four-stroke engine

This paper discusses the use of the fuels propane and butane–propane (80:20) in a four-stroke engine made to function with gasoline (petrol). The experiment covered gas emissions, emissions temperature and fuel consumption. It was observed that gas emissions were reduced compared with gasoline. The reduction for carbon monoxide emissions was greater when butane–propane was used. The same was true for hydrocarbon emissions when the electrical load was below 1500 W, but above 1500 W propane performed better. Higher emissions temperatures were observed with both alternative fuels. Under unloaded conditions the emissions from propane combustion have higher temperature, whereas under full load conditions the emissions from the combustion of the butane–propane mixture have higher temperature. The consumption of propane is lower than that of the mixture.

Catalyst regeneration via chemical treatment and emission tests at idle speeds

Abstract The present paper examines the possibility of chemical treatment of used catalysts for the purpose of improving catalytic efficiency. The proposed method inserts the catalyst in a bath of a strong organic solvent that dissolves oil, soot and fuel residues, cleaning the active surface of the catalyst. The tests were conducted at low (750 r/min) and high (3100 r/min) idle speeds. The experimental results based on CO, HC and catalyst inlet-outlet temperature difference measurements indicate that after treatment the catalytic efficiency improves considerably (>25 per cent) at low idle (750 r/min). The improvement is even higher at high idle (3100 r/min), exceeding 40 per cent. Therefore, there are strong indications that, if car catalysts underwent a similar treatment at regular service intervals, e.g. every 20 000 km, engine emissions could be considerably reduced and catalyst operational life extended.

The Fuel Temperature Variation Used as Fuel Diesel-Palm Oil Mixtures under Constant Fuel Consumption

This work examines the effect of fuel temperature in the gas emissions that is used in a four-stroke diesel engine under maximum constant fuel consumption. The fuel temperatures that were used are 20 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃ and 80 ℃. The engine was functioned under full load condition when it was using different mixtures of diesel-palm oil as fuel. For those fuel temperatures and for any mixture of fuel the gas emissions of carbon monoxide (CO), hydrocarbons (HC), nitrogen monoxide (NO) and rotate speed of engine are examined.