Research On The Treatment Technology Of ASH Pollution On The Heating Surface Of Boiler In Power Station

As for the boiler in power station,during the process of its operation,ash deposit and slagging will occur and even coking when seriously.Regular blowing of ash deposit can effectively reduce the accumulation of ash pollution and the probability of slagging and coking,and then improve the operation efficiency of the boiler.However,ash blowing is closely related to the actual operation of the boiler unit,therefore,it is very important to establish the monitoring model of ash deposition trend for the heating surface and instruct ash blowing in practice according to the monitoring situation.Based on the background,significance and the research status of ash deposition in domestic and foreign,firstly,a 660MW boiler in power station is selected as the research object,then analyzed the characteristics of the traditional thermodynamic model.Secondly,the whole boiler modeling technology is studied,treating all heating surfaces as a whole,and then establish the whole boiler thermodynamic model,through iterative checking,finally obtain the accurate and objective operational data.Thirdly,in order to analyze the characteristics of the fouling tendency and ash blowing in boiler heating surfaces effectively,according to the signal characteristics of each heating surface,a filter based on Fourier transform and a wavelet analysis filter are designed.Through comparative experiments,the results show that the wavelet analysis filter is more reliable and accurate,it has the advantage of characterizing the local features of the signal in both time and frequency domain.At the same time,the technology of using wavelet packet analysis to reflect the high frequency details in the signal is studied.Finally,based on the denoised signal,the model of ash deposition trend for heating surface in the boiler is established,and the equivalent enthalpy drop method is used to analyze the difference of economic benefits after change the ash blowing mode.The rationality and reliability of the whole boiler modeling are proved by ash blowing test and model validation test,and through the filter noise reduction of the monitoring signal,the feasibility of the heating surface ash treatment technology of the power station boiler is been confirmed,that is blowing ash on demand.Finally,the equivalent enthalpy drop method is used to calculate and analyze the change of economic profit caused by the adjustment of ash blowing mode on a single heating surface.