Material level measuring method for straight-blowing double-inlet and double-outlet steel ball coal mill

Abstract

The invention discloses a method for measuring material level of a direct firing dual-inlet and dual-outlet ball mill system, which comprises the following steps of: 1. temperature measurement, in which signals are input into a DCS system; 2. coal supply characteristic test, in which obtained data are arrayed from low to high, and the highest temperature T1max and the lowest temperature T1min are obtained; 3. data acquisition, in which the maximum value of the entrance temperature T2max and the minimum value of the entrance temperature T2min and the average entrance temperature T2 are recorded; and 4. algorithm configuration, in which the data obtained in step 2 and step 3 are substituted for in functions, the sum of function 1 and function 2 is a simulated material level value, and the simulated material level can be regarded as an actual material level for implementing automatic material feeding. The method has the advantages of solving the problem of difficult measurement of the material level, accurately reflecting the change of the material level, meeting the requirement of rapid and substantial load change of a machine set, having stable performance and little maintenance workload, saving equipment investment and having obvious effect of energy conservation.

Description

technical field [0001] The invention belongs to the technical field of thermal power generation, and relates to a method for measuring the material level of a direct blowing type double-inlet and double-outlet steel ball coal mill. Background technique [0002] At present, the direct-blowing double-inlet and double-outlet steel ball coal mill widely used in thermal power plants uses steel balls, coal lumps, coal particles and coal powder as its working medium, and the material level is difficult to measure. The known electric ear material level measuring device and differential pressure material level measuring device are still difficult to achieve the effect of automatic input of material level, which often leads to the load scheduling capacity of this type of unit not keeping up. Among them, the signal of the electric ear material level measuring device is often interfered by the noise of the adjacent running coal mill. The pollution of the microphone caused by the powder...

AI Technical Summary

Problems solved by technology

The pollution of the microphone caused by the dust leakage of the coal mill running under positive pressure will cause measurement errors

Changes in the amount of balls loaded in the coal mill will also cause changes in the noise signal of the coal mill, making the signal unstable and prone to drift

The pressure pipe and peripheral measuring pipe of the differential pressure material level measurement device are prone to leakage, once this happens, it will cause serious errors in material level measurement

Furthermore, the differential pressure material level measurement device uses a lot of equipment, such as gas storage tanks, solenoid valves, pressure transmitters, PLC (programmable logic controller), etc., one needs to be purged regularly, and the other is sometimes malfunctioning. Affect the accuracy of measurement; moreover, due to the wear of steel balls, steel balls need to be added, and the addition of steel balls also affects the accuracy of measurement; in addition, the humid air in rainy areas will also increase the moisture content of raw coal, affecting the coal mill Outlet temperature, maintaining a constant material level is not conducive to stable combustion of the boiler