METHOD OF CONTROLLING COMBUSTION IN A CFB BOILER PLANT

摘要

A method of controlling combustion in the furnace of a circulating fluidized bed boiler plant, the method comprising in first stable load conditions the steps of: feeding fuel at a first fuel feeding rate, proportional to the first load, into the furnace;feeding a feed stream of oxygen at a first oxygen feeding rate, adjusted to maintain a predetermined first oxygen/fuel ratio, into the furnace, so as to combust the fuel at the first fuel feeding rate, whereby a bed char inventory is being maintained in the furnace, and in conditions of increasing the load from the first stable load conditions, the steps of : feeding fuel at a second fuel feeding rate into the furnace, wherein the second fuel feeding rate is higher than the first fuel feeding rate, and feeding a feed stream of oxygen at a second oxygen feeding rate into the furnace, wherein in the conditions of increasing the load the oxygen/fuel ratio is higher than the first oxygen/fuel ratio, so as to combust the fuel at the second fuel feeding rate and to decrease the bed char inventory by combusting char of the bed char inventory.