ABSTRACT

The rate of carbon monoxide (CO) emission increase in Nigeria has become a global issue owing to the rate at which household and businesses use portable generator as an alternative to electricity dilemma. The study compares the CO exhaust emissions and fuel consumption of small internal combustion engines operated with SAE 40 oil and a Nigerian based gasoline. In this study, four models of the generator (Sumec Fireman, Elepaq, Tiger and Constant) with small portable combustion engines and a nominal power of 6.5 KVA equipped with a carburetor for fuel mixture preparation was studied in Ebonyi State University, Abakaliki located in Ebonyi State, the Southeast State of Nigeria. CO emissions rate and fuel consumption were measured with the gradual loading of the combustion engine. CrowconGasman(mode 19256h) CO exhaust emission analyzer was used for the emission measurement. The fuel analysis model was employed for the analysis. The result shows that the emission rate of CO at 75 %(1725W) load and no-load is  1438 g/h and 357.5g/h for Sumec fireman. Also 1031 g/h and 383.75 g/h for Elepaq, 1512 g/h and 684g/h for Tiger. Finally, 988 g/h and 347g/h for Constant generator. All the values obtained at both the highest load and no-load condition were above the permissible limit (75g/h) of emission standard proposed by the US Consumer Product Safety Commission for portable generator sets, powered by one cylinder generator having the highest rate of emission rate as well as fuel consumption. Fuel consumption rate is obtained to be 1.97 litre/h at 75% load and 0.98litre/h at no-load condition for Sumec fireman, same as 1.95 litre/h and 1.01litre/h for Elepaq, 2.05 litre/h and 1.08litre/h for Tiger, 0.66 litre/h and 0.49 litre/h for Constant generator model respectively. Production of carbon monoxide and hydrocarbons is high in the use of a generator engine due to lack of simple engine control emission system and absence of additional emission control device (catalytic converter).