| Combusting in furnace, pulverized coal releases radiant energy immediately, which could reflect the exothermal change in the furnace swiftly, viz. the change of fuel quantity and coal combustion ratio from the physical point. By investigating the relationships between radiant energy signal and the heat absorption of boiler, the rule of change between the heat release and the heat absorption of boiler could be revealed, in order to provide guidance for monitoring and diagnosing and optimal controlling of boiler operation. Besides, there are two steam temperature control methods: one is to mount the cooling spray equipment on steam pipe; the other one is to change the heat of the heat transfer surface in flue gas side. It has indicated that by studying the relation of radiant energy signal and the heat absorption of boiler, instructions of how to introduce radiant energy signal into cooling spray system can be made and there is the possibility to adjust steam temperature through regulating the ratio of the heat absorption of flue gas side and the total heat by the radiant energy.The essay introduces the experimental research system and the principle and method of radiant energy signal acquisition. By carrying out experiments under variant working conditions, qualitative analysis is made on the rule of change of radiant energy inside the furnace and endothermal amount of the heat transfer surfaces such as water wall, superheater, reheater, economizer and air preheater. Thereafter, based on this analysis a static mathematical model of radiant energy signal and heat absorption of boiler is set up by processing experimental data under certain conditions. Furthermore, radiant energy signal is introduced into the control system of the superheated steam temperature in the boiler of the power plant using the inner relationship between the radiant energy and the heat absorption of superheater to make the cooling spray equipment work in advance, and the control effect has proved good.
|
PDF Full Text Request