How ballast affects the heat transfer in the intense combustion zone of boilers

The paper reviews the process of preparing and feeding the combustibles in the context of how combustion occurs in the furnaces of boiler units; the review helps define the requirements to the fuel flow and composition. At various steps, the fuel flow is mixed with excess air and ballast water, which affects heat transfer and combustion processes occurring in the boiler. The role of ballast is analyzed in two steps: first the paper finds how excess air affects the flow and the radiation properties of the products resultant from the combustion of fuels of three different compositions. Then the paper calculates the combined effects of excess air and ballast water on the eigen-radiation flux in the combustion of coal, sulfuric fuel oil, natural and industrial gases. Estimates use the fundamental coefficients of conservation laws as well as the reference data on the properties of the considered fuels. Analysis has found the complex reduction in gas temperature which we herein refer to as the coefficient of thermal depression. Given that coefficient, the paper presents the eigen-radiation fluxes for four model fuels and discusses the applicability of research results.