Staged supply of fuel and air to the combustion chamber to reduce emissions of harmful substances

The paper presents the results of numerical experiments on the implementation of Over Fire Air (OFA) technology at a coal burning thermal power plant (TPP) in order to reduce emissions of harmful substances into the atmosphere. To implement the OFA technology, various options for supplying additional air through injectors in the upper part of the combustion chamber have been studied. For the first time, various heights (h = 8 m, 9 m, 10 m, 11 m, 12 m) of the location of OFA injectors in the combustion chamber at the kazakh TPP were studied. For the first time, different volumes of additional air supply through the injectors are simulated when OFA is 0% this is the base case (traditional combustion) and when OFA is 5%, 10%, 15%, 18%, 20%, 25% and 30% of the total volume air required for complete combustion of the fuel. It is shown that at the optimal location height of OFA injectors (h = 9 m), an increase in the volume of additional air to 18% leads to a decrease in the concentrations of carbon monoxide CO by about 36%, and nitrogen dioxide NO2 by 25% compared with the base case (OFA = 0%).