Combustion Fundamentals

Introduction Combustion is the controlled release of heat due to the chemical reaction between a fuel and an oxygen source. The incineration of sludge cake is a combustion process. The volatile fraction of the total solids in sludge cake is the fuel that ultimately reacts with oxygen and releases heat. The feature that makes the combustion of sludge cake different from the more common fuels is its high moisture content. The amount of heat required to convert water from liquid to vapor is very high. A major portion of the heat released when sludge cake is combusted must be used to evaporate cake moisture. Thus, only the smaller remaining fraction is available to raise the temperature of the products of combustion to proper levels.