Improving combustion air balance is crucial for optimizing the efficiency of a coal-fired boiler and reducing emissions. When combustion air is properly balanced, it ensures that the fuel (coal) burns completely, which minimizes the production of harmful emissions such as carbon monoxide, unburned hydrocarbons, and particulate matter. Adequate oxygen levels in the combustion process facilitate more complete combustion, leading to a cleaner exhaust.
When the air supply is too low, it can result in incomplete combustion, producing various pollutants. Conversely, too much air can lead to higher temperatures in the combustion chamber, which might increase nitrogen oxides (NOx) emissions. Therefore, achieving a precise combustion air balance helps enhance fuel efficiency and reduces the environmental impact of emissions.
Other options may lead to potential increases in emissions or inefficiencies. Reducing air supply can exacerbate incomplete combustion, while increasing the coal feed rate may lead to a linear increase in emissions if combustion conditions are not optimal. Using less coal could lessen emissions, but it may not be a practical or feasible long-term solution compared to optimizing the combustion process itself.