JP4901496B2 - Operation method for unit when coal boiler has increased unburned in ash - Google Patents

Description

  The present invention relates to a unit-compatible operation method when an unburned amount in ash of a coal boiler of a thermal power plant is increased.

  The increase in the unburned content in the ash of coal boilers at thermal power plants is likely to occur when the boiler tube and furnace are clean after regular inspections, improving heat absorption in the furnace and lowering the combustion temperature. When the unburned amount in the ash increases after regular inspection, as a unit operation measure, increase the O2 setting to improve the flammability without any such operation procedure and judgment criteria, or increase the number of mills to be crushed The vehicle was operated with increased performance, and the unburned content was actually measured to confirm the reduction.

  Thus, since the operation procedure of unburned matter reduction was not established, there existed problems, such as reduction in boiler efficiency, increase in power in a power plant, and ineffective use of ash.

  Therefore, as described in claim 1, the present invention provides a means for comparing the analysis result of the unburned ash in the target unit with the reference value, and the unburned boiler constituting the unit when the reference value is exceeded. Means for comparing the minute average value with the reference value, means for increasing the oxygen supply set value from the optimum set value to the maximum set value when the average value exceeds the reference value, and setting the oxygen supply set value to the maximum set value The present invention provides a unit-compatible operation method for increasing the unburned amount in ash of a coal boiler, comprising means for increasing the number of mills to be operated when the unburned amount in ash exceeds a reference value even if the increase operation is performed.

  Further, according to the present invention, as described in claim 2, the means for comparing the analysis result of the unburned ash in the target unit with the reference value, and the unburned boiler constituting the unit when the reference value is exceeded. Means for comparing the minute average value with the reference value, means for increasing the oxygen supply set value from the optimum set value to the maximum set value when the average value exceeds the reference value, and setting the oxygen supply set value to the maximum set value Unit operation method for increasing the unburned content in ash of coal boilers, comprising means for gradually reducing the oxygen supply set value to the optimal set value when the unburned content in ash is below the reference value after increasing operation Is to provide.

  Further, according to the present invention, as described in claim 3, the means for comparing the analysis result of the unburned ash content of the target unit with the reference value, and the unburned boiler constituting the unit when the reference value is exceeded. Means for comparing the minute average value with the reference value, means for increasing the oxygen supply set value from the optimum set value to the maximum set value when the average value exceeds the reference value, and setting the oxygen supply set value to the maximum set value A means to increase the number of mill operations when the unburned amount in ash exceeds the reference value even if the increase operation is performed, and a decrease in the number of mill operations when the unburned amount in ash falls below the reference value by increasing the number of mill operations The unit corresponding operation method at the time of the unburned part increase in the ash of the coal boiler which consists of means to perform is provided.

  Further, according to the present invention, as described in claim 4, in the operation method corresponding to the unit when the unburned amount in the ash of the coal boiler according to claim 3 is increased, the unburned in ash is obtained by means for reducing the number of mills operated. The present invention provides a unit-compatible operation method for increasing the unburned fraction in ash of a coal boiler having means for gradually decreasing the oxygen supply set value from the maximum set value when the minute is below the reference value.

  Further, according to the present invention, as described in claim 5, in the unit corresponding operation method when the unburned amount in the ash of the coal boiler according to claims 1 to 4 is increased, the reference value of the unburned amount in the ash is almost equal. The operation method corresponding to the unit at the time when the unburned content in the ash of the coal boiler which is 5% increases is provided.

  Further, according to the present invention, as set forth in claim 6, in the unit-corresponding operation method when the unburned amount in the ash of the coal boiler according to claims 1 to 5 is increased, the optimum oxygen supply set value is 3.3 to The unit operation method when the unburned content of coal boiler in ash is 3.4% is provided.

  Further, according to the present invention, as set forth in claim 7, the maximum oxygen supply set value is about 3.6 in the unit corresponding operation method when the unburned amount in the ash of the coal boiler according to claims 1 to 6 is increased. It provides a unit-compatible operation method when unburned coal in ash is increased.

  Further, according to the present invention, in the operation method corresponding to the unit when the unburned fraction in the ash of the coal boiler according to claim 8 is increased, the oxygen supply set value is changed from 3.6% to 0.1% of the maximum oxygen supply set value. It is intended to provide a unit-compatible operation method for increasing the unburned amount in ash of a coal boiler, which consists of lowering toward an optimum oxygen supply set value.

  Further, according to the present invention, as described in claim 9, in the operation method corresponding to the unit when the unburned amount in the ash of the coal boiler according to any one of claims 1 to 8 is increased, the optimum mill operation number is increased by five. The unit corresponding operation method at the time of the unburned part increase in the ash of the coal boiler whose number of mill operation is six is provided.

  According to the unit corresponding operation method at the time of increase of unburned in ash of the coal boiler according to the present invention, means for comparing the analysis result of unburned in ash of the target unit with the reference value, and when exceeding the reference value Means for comparing the unburned fuel average value of the boiler constituting the unit with the reference value, means for increasing the oxygen supply set value from the optimum set value to the maximum set value when the average value exceeds the reference value, and oxygen Even if the supply set value is increased to the maximum set value, if the unburned amount in the ash exceeds the reference value, it has a structure consisting of means for increasing the number of mill operations, so that the target unit can be ashed at any time. Compare the analysis result of unburned matter with the reference value.If the reference value is exceeded, compare the unburned average value of the individual boilers constituting the unit with the reference value. It is only necessary to continue the measurement and watch the situation. When the value exceeds the reference value, the oxygen supply set value is increased from the optimal set value to the maximum set value to improve the combustibility and reduce the unburned amount, and the oxygen supply set value is set to the maximum set value. If the unburned amount in ash exceeds the reference value even if the operation is increased, the mill grindability of coal can be improved and the unburned amount can be reduced by increasing the number of mills operated. There is an effect that an early reduction of unburned matter can be achieved when the unburned amount of coal boiler in ash is increased.

  Further, according to the present invention, as described in claim 2, the means for comparing the analysis result of the unburned ash in the target unit with the reference value, and the unburned boiler constituting the unit when the reference value is exceeded. Means for comparing the minute average value with the reference value, means for increasing the oxygen supply set value from the optimum set value to the maximum set value when the average value exceeds the reference value, and setting the oxygen supply set value to the maximum set value When the operation is increased and the unburned ash content is below the reference value, the oxygen supply set value is gradually reduced to the optimum set value. There is an effect that the oxygen supply set value can be gradually reduced to the optimum set value step by step so as not to exceed.

  Further, according to the present invention, as described in claim 3, the means for comparing the analysis result of the unburned ash content of the target unit with the reference value, and the unburned boiler constituting the unit when the reference value is exceeded. Means for comparing the minute average value with the reference value, means for increasing the oxygen supply set value from the optimum set value to the maximum set value when the average value exceeds the reference value, and setting the oxygen supply set value to the maximum set value A means to increase the number of mill operations when the unburned amount in ash exceeds the reference value even if the increase operation is performed, and a decrease in the number of mill operations when the unburned amount in ash falls below the reference value by increasing the number of mill operations Therefore, the number of mill operation units can be reduced to the optimum number so that the unburned ash content does not exceed the reference value.

  Further, according to the fourth aspect of the present invention, in the operation method corresponding to the unit when the unburned portion in the ash of the coal boiler according to the third aspect is increased as described in the fourth aspect, the ash is reduced even if the number of mill operations is reduced to the optimum number. By having a means to gradually reduce the oxygen supply set value from the maximum set value to the optimal set value when the unburned content in the coal is below the reference value, the coal boiler can be quickly There is an effect that the unburned component can be reduced to an appropriate reference value in an appropriate operating state.

  Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

In FIG. 1, Step 1 is an analysis value input means for inputting the analysis result of unburned matter in the ash of the electric dust collector of the target unit to the reference value comparison means in Step 2.
In the case of the embodiment, the reference value is approximately 5%. If the analysis value is less than 5% in the reference value comparison means in step 2, the determination in step 2 is NO, and the optimum mill based on the optimum oxygen concentration in step 3 is determined. The operation of the boiler by the number of operating units will continue. In the case of the examples, the optimum oxygen concentration in the furnace is 3.3 to 3.4%, and the optimum number of mills is five.

If the analysis value is 5% or more in the reference value comparison means in step 2, the determination in step 2 is YES, and the average value comparison means in step 4 determines the average value of unburned ash in each boiler as the reference value. Will be compared.
In the average value comparison means in step 4, if the average value is less than 5%, the determination in step 4 is NO, and the operation of the boiler by the optimum number of mills operated by the optimum oxygen concentration is continued by the state observation means in step 5, Considering the influence of the coal condition of the fuel, the situation will be observed for about a week.

Thereafter, if the analysis value is less than 5% by the reference value comparison means for comparing the analysis value of the unburned portion of the target unit in step 6 with the reference value, the determination in step 2 is NO and the optimum oxygen concentration in step 7 The operation of the boiler with the optimal number of mills operated by will continue.
If the average value is 5% or more in the average value comparison means in step 4 above, the determination in step 4 is YES, and the oxygen concentration is set to 3.6% by the oxygen concentration maximum operation means in step 8. And improve the combustibility.

In step 8, after the oxygen supply set value is increased to the maximum set value, the analysis value is less than 5% by the reference value comparison means for comparing the analysis value of the unburned portion of the target unit in step 9 with the reference value. If there is, the determination in step 9 is NO, and the means for gradually reducing the oxygen supply set value in step 10 to the optimum set value is 0.1% in a cycle of about one week toward the optimum oxygen concentration by 0.1%. Decrease gradually and continue to operate the boiler with the optimal number of mills.
In addition, even if the oxygen supply set value is increased to the maximum set value by the reference value comparing means in step 9, if the unburned in ash exceeds the reference value 5%, the determination in step 9 is YES, In the case of this embodiment, the mill operation number increasing means in step 11 increases the number of mill operation from the optimum 5 to 6 to improve the mill grindability of coal supplied to the boiler.

Thereafter, if the analysis value is less than 5% by the reference value comparison means for comparing the analysis value of the unburned portion of the target unit in step 12 with the reference value, the determination in step 12 is NO, and the number of mill operations in step 13 By reducing the number of mills, the operation number of mills is reduced to the optimal number of five, and the analysis value is less than 5% by the reference value comparison means for comparing the analysis value of the unburned portion of the target unit in step 14 with the reference value. If so, the determination in step 14 is NO, and the means for gradually reducing the oxygen supply set value in step 10 to the optimum set value is 0.1 to bring O2 to the optimum oxygen concentration in a cycle of about one week. It is possible to continue the operation of the boiler with the optimum number of mill operation units at the optimum oxygen concentration of 3.3 to 3.4%.
Here, in step 12 or 14, if the analysis value is 5% or more, the operation returns to step 11 and the operation with 6 units with the increased number of mills is repeated, and the optimum of step 10 is obtained through steps 12, 13, and 14. The aim is to continue the operation of the boiler with an optimal mill operation number of 5 at an oxygen concentration of 3.3 to 3.4%.

If the average value is 5% or more in the average value comparison means in step 6 above, the determination in step 6 is YES, and the oxygen concentration is set to 3.6% by the oxygen concentration maximum operation means in step 15. And improve the combustibility.
In step 15, after the oxygen supply set value is increased to the maximum set value, it may take 2 to 4 months after the previous step 8. If the analysis value is less than 5% by the reference value comparison means for comparing with the reference value, the determination in step 16 is NO, and the means for gradually decreasing the oxygen supply set value in step 17 to the optimum set value In a cycle of about one week, O2 is gradually decreased by 0.1% toward 3.3% of the optimal oxygen concentration, and the operation of the boiler with the optimal number of mills is continued.

  If the analysis value is 5% or more in the reference value comparison means in step 16, the determination in step 16 is YES, and the average value comparison means in step 18 determines the average value of unburned ash in each boiler as the reference value. If the average value is less than 5% of the reference value, the process returns to the operating means for increasing the oxygen supply set value in step 15 to the maximum set value.

  If the average value exceeds 5% by the average value comparison means in step 18, the determination in step 18 is YES, and in this embodiment, the number of mill operations is determined by the means for increasing the number of mill operations in step 11 above. Increased to 6 units, the mill grindability of coal supplied to the boiler will be improved. After that, through steps 12, 13, and 14, the operation of the boiler with the optimum number of mills operated at the optimum oxygen concentration of 3.3 to 3.4% in step 10 is continued.

The flowchart of one Example in the method of this invention.

Claims (9)

Means to compare the analysis result of unburned ash in the target unit with the reference value, and if the reference value is exceeded, compare the unburned average value of the individual boilers constituting the unit with the reference value for a certain measurement period Means for increasing the oxygen supply set value from the optimum set value to the maximum set value when the average value exceeds the reference value, and unburned in ash even if the oxygen supply set value is increased to the maximum set value. An operation method corresponding to a unit when an unburned portion in ash of a coal boiler is increased, comprising means for increasing the number of mill operation from the optimum operation number when the minute exceeds a reference value. Means to compare the analysis result of unburned ash in the target unit with the reference value, and if the reference value is exceeded, compare the unburned average value of the individual boilers constituting the unit with the reference value for a certain measurement period Means for increasing the oxygen supply set value from the optimum set value to the maximum set value when the average value exceeds the reference value, and increasing the oxygen supply set value to the maximum set value to increase the oxygen supply set value to the maximum set value. The unit corresponding operation method at the time of the increase in the unburned part in the ash of the coal boiler, comprising means for gradually decreasing the oxygen supply set value to the optimum set value when the value is lower than the reference value. Means to compare the analysis result of unburned ash in the target unit with the reference value, and if the reference value is exceeded, compare the unburned average value of the individual boilers constituting the unit with the reference value for a certain measurement period Means for increasing the oxygen supply set value from the optimum set value to the maximum set value when the average value exceeds the reference value, and unburned in ash even if the oxygen supply set value is increased to the maximum set value. It consists of means to increase the number of mill operations when the minute exceeds the reference value, and means to increase the number of mill operations and decrease the mill operation number to the optimum operation number when the unburned ash content is below the reference value. Operation method for units when coal boilers have increased the amount of unburned ash. In the unit corresponding operation method at the time of increase in unburned in ash of a coal boiler according to claim 3, when oxygen unburned in ash falls below a reference value by means of decreasing the number of mills operated, the oxygen supply set value is set to the maximum. The unit corresponding operation method at the time of the increase in the unburned content in the ash of the coal boiler having means for gradually decreasing the value from the value to the optimum set value. In the unit corresponding | compatible operation method at the time of the unburned part increase in the ash of the coal boiler of Claims 1 thru | or 4, the reference value of the unburned part in the ash is about 5%, and the unburned part in the ash of the coal boiler is increased. Unit compatible operation method. In the unit corresponding | compatible operation method at the time of the unburned part increase in the ash of the coal boiler of Claims 1 thru | or 5, the oxygen concentration in a furnace by the optimal oxygen supply setting value is 3.3 to 3.4%. Unit-compatible operation method when unburned ash increases. 7. The operation method corresponding to a unit when the unburned portion of ash in a coal boiler is increased according to claim 1 , wherein the oxygen concentration in the furnace according to the maximum oxygen supply set value is approximately 3.6%. Unit-compatible operation method when fuel is increased.

In the unit corresponding | compatible operation method at the time of the unburned part increase in the ash of the coal boiler of Claim 6 or 7, an oxygen supply setting value is optimal oxygen supply setting 0.1% from 3.6% of a maximum oxygen supply setting value. The unit operation method when the unburned content in the ash of the coal boiler increases, which consists of lowering toward the value. In the operation method corresponding to the unit when the unburned amount in the ash of the coal boiler according to any one of claims 1 to 8 is increased, the unburned coal in the ash of the coal boiler having the optimum number of mill operation units of 5 and the increased number of mill operation units of 6 units. Unit-compatible operation method when increasing minutes.

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