Coal-fired boilers used for production and domestic heating are mostly coal-fired boilers under 4 ton. Starting from the transformation of the coal-fired boiler hearth, furnace arch, furnace wall, waste heat recovery, dust removal device, feeding system, control system, etc., the coal-fired boiler is transformed into a fully automatic biomass boiler, so that the energy efficiency is increased to 80% -85% .
Analysis of wood pellet fuel combustion characteristics
Sawdust particles are a renewable carbon source, featuring huge output, wide distribution, low sulfur, low nitrogen, fast growth, and low carbon dioxide emissions.
Wood pellet combustion is mainly controlled by the following conditions:
(1) A certain temperature;
(2) A certain amount of air (oxygen);
(3) The degree of mixing of fuel and air (oxygen);
(4) Combustibles in fuel Time of intense chemical reaction with oxygen in the air.
The ignition temperature of the biomass fuel wood pellets is 250-400 ° C, which is lower than that of coal (the ignition temperature of coal is 400-500 ° C), and the increase in temperature is supplied by the ignition heat. The combustion process of biomass fuel is a process in which volatile and combustible components and oxygen in the air are violently combined to release heat, so the supply of oxygen determines the process of the combustion reaction. By controlling the amount of oxygen supplied, its combustion reaction can be well controlled. If the structure of the currently operating domestic and industrial boilers is directly used without biomass particulate fuel, the boiler will have serious smoke emission, low efficiency, and dust pollution. Therefore, the use of biomass particulate fuel boilers needs to be equipped with special secondary air supply equipment to enhance the oxygen supply so that it can fully burn, effectively increase the temperature of the furnace, reduce carbon monoxide and smoke emissions and heat loss.