Experimental Investigations of the Effects of Secondary Air Injection on Gaseous Emission Profiles (NO<sub>x</sub>, NO, NO<sub>2</sub>, CO) and Hydrocarbons (C<sub>x</sub>H<sub>x</sub>) in Cookstoves Using Charcoal from <i>Eucalyptus glandis</i>
- 1 Institute of Energy and Environmental Technology, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya
- 2 Institute of Energy and Environmental Technology, Jomo Kenyatta University of Agriculture and Technology (JKUAT), Nairobi, Kenya
- 3 Department of Mechanical Engineering, JKUAT, Nairobi, Kenya
- 4 Department of Mechanical Engineering, JKUAT, Nairobi, Kenya
- 5 Department of Chemistry, JKUAT, Nairobi, Kenya
Abstract
Use of biomass in domestic cookstoves lead s to the release of oxides of nitrogen (NO x ), nitric oxide (NO), nitrogen dioxide (NO 2 ), carbon monoxide (CO) and hydrocarbons C x H x that can be detrimental to health of the public and the environment. Attainment of complete combustion is the best strategy for mitigating the release of these emissions. This study sought to experimentally determine the effects of secondary air injection on the emission profiles of NO x (NO & NO 2 ), CO and C x H x in a charcoal operated cookstove. Charcoal from Eucalyptus glandis was bought from Kakuzi PLC. Composites from three batches were analyzed for chemical composition and the stoichiometric air equivalent. Proximate analysis data show that the charcoal composed 58.72% ± 3.3% C, 15.95% ± 1.2% Volatile Matter, 4.69% ± 0.55% Moisture, 20.7% ± 0.8% Ash, High heat value (HHV) of 30.5 ± 1.1 and 29.3 ± 1.3 Low heat value (LHV) (MJ/kg) with a chemical formula of C 18 H 2 O and a stoichiometric air requirement of 5.28 ± 0.6 with a fuel flow rate of 1 kg fuel/hr. Emission profiles for CO and C x H x reduced significantly by 70% and 80% respectively with secondary air injection whereas those of NO x increased by between 15% and 20% for NO 2 and NO. The study reveal s that secondary air injection has potential to mitigate on emission release, however other measures are required to mitigate NO x emissions.
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