Efficient boiler combustion minimizes heat loss and reduces environmental impact by optimizing the use of fuel elements like carbon, hydrogen, and sulfur.

@Su_G #BoilerManual #UnitDescription #Section1 #Page18 COMBUSTION & HEAT TRANSFER A boiler requires a source of heat at a sufficient temperature level to produce steam. At Baldwin, coal is the fuel utilized for the generation of steam and it is burned directly for this purpose in the cyclones and boiler furnace. Combustion may be defined as the rapid chemical combination of oxygen with the combustible elements of fuel. There are just three combustible chemical elements of significance - carbon, hydrogen and sulfur. Sulfur is of minor significance as a heat source, but it can be of major significance in corrosion and environmental considerations. The objective of good combustion is to release all of the heat while minimizing losses from combustion imperfections and superfluous air. ------------------------------------------------- 18 ------------------------------------------------------

@Su_G #BoilerManual #UnitDescription #Section1 #Page19 The combustion of the combustible elements and compounds of the fuel with all the oxygen requires a temperature high enough to ignite the constituents, mixing or turbulence, and sufficient time for complete conbustion. These factors are referred to as the three T's of combustion. The heat released as a result of combustion is then transferred to the heat absorbing surfaces of the boiler. In boiler practice, the heat of combustion of a fuel is the amount of heat expressed in Btu, generated by the complete combustion, or oxydation, of a unit weight of fuel (1 lb.). There are three modes of heat transfer; radiation, convectin and conduction. All the varied phases of heat transfer involve one or more of these modes coupled with a temperature difference between a heat source and heat receiver. Radiation is the transfer of heat energy between bodies without dependence on the presence of water in the intervening space. All matter radiates, and the transfer of heat (thermal radiation) is one important manifestation of this phenomenon. Radiation occurs when a hot object gives off heat in a straight line away from itself. Radiation is considered the primary mechanism of heat transfer in a furnace, with heat radiating from the hot fire to the cooler furnace walls. Convection is the transfer of heat from one point to another within a fluid (gas or liquid) by the mixing of one part with another. Heat is transferred by convection when boiler flue gases pass over the tube surface and also when the steam or water pass over the internal surfaces of the tube. Convection is the primary mechanism of heat transfer which occurs in the convection pass of the boiler. Conduction is the transfer of heat from one part of a body to another part of the same body, or from one body to another when they are in physical contact. ------------------------------------------------- 19 ------------------------------------------------------