Study On The Combustion Characteristics Of Gasified Char In Fluidized Bed Experimental Rig

Coal is one of the most important primary energy all of the world, Clean coal technologies will be paid a high degree of attention and rapid developed under the current energy situation in our country. However, at present the development of technology of coal gasification encountered many technical problems, Including pressurized ash agglomerating fluidized bed Coal Gasification system to produce high carbon gasified char is difficult to be used by the conventional combustion technologies, Therefore, research on the combustion of gasified char and utilize the coal in a better way is important.In this paper, we will research on burnout rate, pollutant emissions and other combustion characteristics of gasified char under different furnace temperature ,excess air ratio and air velocity in fluidized bed, The results show that: Furnace temperature increased to 900℃from 800℃, carbon content of fly ash decline, burnout rate of fly ash was significantly increased about 12 percentage points. Excess air ratio increased to 1.3 from 1.1, burnout rate of fly ash significantly increase; At the same time by the flow of the wind speed 3.25m/s down to 2.25m/s, the burn rate was increased about 10%. carbon content of gasified char is lower near the dense;Gas measurement results show that: With the furnace temperature and excess air ratio increases, NOx emissions increase, both of the largest increase is among 50 ~ 100ppm; Along the furnace height NOx concentration decreased, the largest decrease is aboat 100ppm; SO2 emission of fly ash combustion in a fluidized bed is very low(20ppm), there is no need desulfurization treatment , the SO2 emission achieve emission requirements.Researching on the influence of the amount of co-combustion of gasified char on circulating fluidized bed boiler thermodynamic performance by thermodynamic calculation and other related calculation, we found that: With the increase in amount of fly ash, the heat loss of incomplete carbon combustion significant increase, and boiler efficiency decreased; Little change in exports of flue gas flow rate, within a reasonable range. Consider the maximum capacity of the bag filter in the boiler, Ultimately we determine the largest mixing amount of Gasified char is 2.5t/h,On this basis, we propose adding fly ash on position of the secondary air finally.