Research on boiler operation monitoring and optimization based on real-time measurement of furnace water-cooled wall H2S atmosphere field
In order to reveal the concentration distribution of H2S in the boiler water wall at different loads,the change of the atmosphere when the load changes,the relationship between H2S and the furnace components CO and SO2,the dis-tribution of H2S in the coking area and the influence of operation adjustment on H2S and NOx,and to guide the operation of the boiler,an on-line monitoring device for the water wall atmosphere was installed on a 300 MW level power plant boiler.The formation law of reducing components such as H2S and CO near the furnace wall and the influence of opera-tion adjustment on the atmosphere in the furnace were systematically studied.The results show that:(1)The overall con-centration of H2S and CO in the furnace is higher at high load,and the higher the load,the more serious the corrosion tendency.(2)When the load decreases from high to low,there is a critical load(40%BMCR).When the load decreases to this critical load,the wall atmosphere begins to change from reducing atmosphere to oxidizing atmosphere.The fur-nace is prone to high temperature corrosion load range of 60%～100%.(3)On the whole,H2S and CO on the wall showed a positive correlation,while H2S and SO2 showed a negative correlation,but at the same time showed a certain degree of independence.(4)The average concentration of H2S in coking area is 537×10-6 higher than that in non-coking area,which is consistent with the phenomenon that the corrosion of water wall in coking area is more serious than that in non-coking area.(5)Turning off the number of over-fire air layers and increasing the operating oxygen can significant-ly reduce the concentration of H2S,with a maximum decrease of 91.4%.However,the decrease of H2S concentration will cause the increase of NOx.Turning off one layer of over-fire air can increase NOx by an average of 109 mg/m3.It is suggested that this contradiction needs to be balanced in actual operation.
High temperature corrosionboilerhydrogen sulfideH2Sreducing atmosphere
国家科技期刊平台
NSTL
万方数据
