Stoker-fired boiler, method of modernization of the stoker-fired boiler and method for reducing emission of dusts in the process of burning solid fuels in the stoker-fired boiler

摘要

A boiler is provided with a travelling mechanical grate (4) located in its furnace zone, with blast zones (5) and with a main air duct (6), delivering an atmospheric air into these zones (5) with help of a blast fan (7). In the under-the-grate space located under end section of the grate (4), having the length equalling from 10 to 40% of the total active length of the grate (4), there is at least one suction zone (8) connected with the first end (9) of the first additional air duct (10) Second end (11) of the duct (10) is connected with a source for negative pressure (12), which generates in the suction zone (8) a pressure lower than the pressure existing above the grate (4) by a value of range form 5 to 100 Pa. A method of modernisation of a typical stoker-fired boiler consists in cutting off of the at least one last blast zone (8) from the main air duct (6) and connecting this zone (8) over an additional air duct (10) with an adjusted negative pressure source (12) generating in this zone (8) a pressure lower than the pressure existing above the grate (4) by a value of range form 5 to 100 Pa. The method for reducing the particle matter emission consists in that in the under-the-grate space located under the end section of the grate (4), having a length equalling from 10 to 40% of the entire active length of the grate (4), a pressure is lowered in relation to the pressure existing above the grate (4) and the pressure difference is maintained in the range from 5 to 100 Pa.