MONITORING METHOD AND DEVICE OF FUEL-AIR MIXTURE DURING COMBUSTION OF FLOOR COAL IN FIRING SYSTEM OF COAL-FIRED POWER PLANT Russian patent published in 2013 - IPC F23N1/02 F23N5/18 F23K3/02 F23K1/00 G01P5/18 

FIELD: power industry.

SUBSTANCE: control device of ratio of fuel and air at combustion of ground coal in a firing device of a coal-fired power plant, which includes means for pneumatic supply of ground coal to burners of the firing device of the coal-fired power plant, as well as means for combustion air supply to burners (13) or to furnace chamber (12) of the firing device of the coal-fired power plant; at least the following devices are located in air flow direction: induced air fan (3) for suction of induced air from atmosphere, mill fan (4) for supply of some part of suction induced air as conveying air for saturation with ground coal, regenerative air pre-heater (5) for pre-heating of suction induced air and some part of conveying air using flue gas heat of the firing device of the coal-fired power plant; first, accumulating mass of regenerative air pre-heater (5) is heated with hot flue gases, and then, it is cooled with induced air or some part of conveying air, an air flow rate control device for control of the air flow rate supplied to furnace chamber (12), an air flow rate control device for control of conveying air flow rate, which is used for pneumatic supply of ground coal, as well as measuring devices (10, 17, 18) for measurement of flow rate of combustion air supplied to furnace chamber (12) and conveying air flow rate, which is used for pneumatic supply of ground coal, and device (8, 11) for dosed supply of pre-selected amount of ground coal to burners (13). For measurement (17, 18) of combustion airflow rate there provided is a correlation measuring device that analyses triboelectric effects on two sensors located in combustion air flow one after another in the flow direction; at that, sensors are located in a system of channels, which carriers combustion air, in the flow direction after regenerative air pre-heater (5), and that in combustion air flow direction before the specified sensors of the correlation measuring device there located is at least one device (2) of dosed supply of small-grained particles to an air flow.

EFFECT: invention allows providing uninterrupted control of the fuel and air ratio at combustion of ground coal in the firing plant.

13 cl, 2 dwg