Combustion control method in refuse incineration furnace

摘要

A combustion control method in a refuse incineration furnace utilizing the combustion heat of refuse for producing steam power, in which the state of combustion is stabilized so that a predetermined quantity of produced stream can be obtained. In the method, the weight of introduced refuse and the level change between levels before and after introduction of refuse are obtained on the basis of values measured by means of a refuse gravimeter attached to a refuse-introduction crane and a refuse level meter 12 for measuring the surface height of refuse in a refuse incineration furnace hopper; and the speed of a drying fire grate 3a for feeding refuse into the furnace is controlled on the basis of a result of comparison of the thus obtained weight and level change of refuse with those obtained in a plurality of times in the past up to the preceding time. Further, a quantity of steam produced in the refuse incineration furnace and a concentration of O2 in exhaust gas are measured; a target quantity of combustion air required for making the quantity of produced steam coincident with a target quantity of produced steam is calculated; the target quantity of combustion air calculated when the measured value of the concentration of O2 in exhaust gas first reaches a predetermined upper limit value is made to be a temporarily set quantity of combustion air; the quantity of combustion air is controlled so as to be coincident with the target quantity of combustion air when the measured value of the concentration of O2 in exhaust gas is not larger than the upper limit value; and the quantity of combustion air is controlled so as to be coincident with smaller one of the target quantity of combustion air and the temporarily set quantity of combustion air when the measured value of the concentration of O2 in exhaust gas is larger than the upper limit value.