Flow Field And Pressure Field, Temperature Field Simulation Of Flue Gas In The Chimney After The Desulphurization

At present wet flue gas desulfurization used in power plant has played an important role in SO₂ emission reduction, at the same time it brings secure hidden trouble on safe function of power plant. Desulphurizing engineering practice indicates that, through the process of wet flue gas desulphurization in power plant, the flue gas's temperature would be below acid dew point, and it results in the seriously corrosion . In view of the above questions, this paper carried out research on three aspects. Acid dew point is the measurement of the important parameters of low temperature corrosion. After wet flue gas desulfurization by the change in the composition of the flue gas, acid dew point will be occurred certain change. The paper selects the various types of coal and calculates acid dew point using foreign variety of acid dew point calculation formulas separately. The calculation results show that, taking the chimney anticorrosive into consideration, the Verhoff formula is advisable for forecasting the acid dew point of flue gas after desulfurization. In addition variety of acid dew point calculation formula hints that whatever fixing GGH or not, the temperature after flue gas desulfurization will be below acid dew point, and FGD tail equipment must be taken anticorrosion measures. By installing the GGH or not and different ways that flue gas flows into chimney, the paper made flow field and pressure field, temperature field simulation of flue gas in the chimney after desulphurization using Fluent software. Calculation results show that pressure of the flue gas which goes through GGH is less than the flue gas's pressure without GGH, which can reduce the corrosion of inner chimney. Compared the way which chimney have a single entry, the flue gas that flows into chimney by the bilateral symmetry entrance wears slightly to the inner chimney,this way can extend the chimney running lifetime. Simulation can be used to guide chimney anticorrosive engineering. Using the fixed fugacity equation and matlab software to simulate condensation acid solution's concentration, the paper reveals that three factors which are flue gas water vapor concentration, surface temperature, gas absolute pressure have the effect on the condensation acid solution's concentration, and finds out that the concentration of condensation acid solution is the key for determining the corrosion rate and acid deposition rate of low-tempera. The predicted value and the related literature value tally.