JP6568420B2 - Boiler operation method and boiler equipment - Google Patents

Description

  The present invention relates to a boiler operation method and boiler equipment.

  The boiler includes a furnace that burns solid fuel using a burner or the like, and a heat transfer tube that is disposed in the furnace in the vertical direction and performs heat exchange. In addition, this heat transfer tube has a primary heater, a primary reheater, and a lower heat transfer unit provided with a economizer, and a secondary heater, a tertiary heater, and a final heater. It is comprised by the upper heat-transfer part provided with a heater and a secondary reheater.

  Among such boilers, for example, in a pulverized coal boiler using coal as a solid fuel, slagging or fouling occurs in which ash in the combustion gas generated by the combustion of coal adheres to and accumulates on the furnace wall and heat transfer tube of the furnace, An ash adhesion layer may be formed. When such ash adhesion occurs, the heat recovery rate at the heat transfer surface of the heat transfer tube is likely to be greatly reduced. Further, when the ash (clinker) adhering to the furnace wall becomes enormous, it may fall from the furnace wall or the like, resulting in a significant fluctuation in the furnace pressure, damage to the heat transfer tube, blockage of the gas flow path, or the like.

  In particular, the upper heat transfer section has a structure in which the combustion gas flows between the heat transfer tubes arranged at a narrower interval than the lower heat transfer section to exchange heat, so that ash is formed in the upper heat transfer section. If it adheres, a large fluctuation in the furnace pressure and a blockage of the gas flow path are likely to occur, and the stable operation of the boiler is hindered. Further, in the vicinity of the burner, the temperature in the vicinity of the furnace wall becomes high due to the radiant heat of the pulverized coal combustion flame, so that ash tends to melt and adhere to a relatively low temperature heat transfer tube, and the heat recovery rate of the furnace tends to decrease.

  Then, the possibility that this ash adhesion occurs is expressed as an index, and a boiler operation method that suppresses ash adhesion based on the index has been proposed (Japanese Patent No. 5342355). In this conventional operation method, focusing on slag, which is a component adhering to the furnace wall and heat transfer tube group, the mixing ratio of multiple types of solid fuel is determined based on the slag ratio calculated for each solid fuel and the composition of the ash component. Has been decided. Specifically, in the conventional boiler operation method, a slag ratio reference value is determined so that the ash adhesion rate is low, and the mixing ratio of a plurality of types of solid fuels is set so that the slag ratio is less than this reference value. By determining, adhesion of ash is suppressed.

  However, in the conventional boiler operation method, the heat recovery rate of the furnace may be lowered in spite of the suppression of ash adhesion. For this reason, a new boiler operation method that can suppress a decrease in the heat recovery rate of the furnace is desired.

Japanese Patent No. 5342355

  This invention is made | formed based on the above situations, and aims at provision of the operating method and boiler equipment of a boiler which can suppress the fall of the heat recovery rate of a furnace.

  As a result of intensive studies, the inventors of the present invention have found that when the adhesion of ash is similar, the use of solid fuel with a high content of hydrous mineral tends to cause a decrease in furnace heat recovery rate, so We focused on the content of hydrous minerals in the ash content of the solid fuel mixture. As a result, it was found that the heat recovery rate of the furnace decreased due to the heat-insulating layer of the ash adhesion layer due to the adhesion of the porous ash resulting from the release of crystal water from the hydrous mineral. Then, the present inventors can stably operate the boiler because it is possible to suppress the decrease in the furnace heat recovery rate by determining the mixing ratio of a plurality of types of solid fuel so that the content of the hydrous mineral is not more than the reference value. The present invention has been completed by finding that it is easy.

  That is, the invention made to solve the above-mentioned problems is a boiler operation method for mixing and burning a plurality of types of solid fuels, the ash content in the plurality of types of solid fuels and the ash content in the ash content Based on the step of acquiring the content of at least one hydrous mineral, the content of the ash and the content of the at least one hydrous mineral in each of the plurality of types of solid fuel obtained in the acquisition step, Determining the mixing ratio of the plurality of types of solid fuels so that the content of the at least one type of hydrous mineral in the ash content of the entire mixture of the plurality of types of solid fuels is equal to or less than a reference value. To do.

  Since the operation method of the boiler determines the mixing ratio of the plurality of types of solid fuel so that the content of the hydrous mineral is below the reference value, the porous ash caused by the release of crystal water from the hydrous mineral Adhesion can be suppressed. Thereby, since the heat insulation of adhesion ash is reduced, the operation method of the boiler can suppress the fall of the furnace heat recovery rate.

  The at least one water-containing mineral may be kaolin or gypsum. Kaolin and gypsum account for a large proportion of the hydrous minerals contained in the solid fuel used in boilers, and are likely to cause a decrease in furnace heat recovery rate. For this reason, the fall of a furnace heat recovery rate can be suppressed more reliably by making the said at least 1 sort (s) of hydrous mineral into kaolin or gypsum.

  As said reference value, 40 mass% is preferable. Thus, by making the said reference value into 40 mass%, the fall of a furnace heat recovery rate can be suppressed more reliably.

  The solid fuel may be coal. In boilers using solid fuel as coal, the furnace heat recovery rate is particularly likely to decrease. For this reason, the operation method of the said boiler which can suppress the fall of a furnace heat recovery rate can be used suitably.

  Therefore, the operation method of the boiler is suitably used for a thermal power plant using a boiler facility using coal as a solid fuel.

  Another invention made to solve the above problems is a boiler facility for mixing and burning a plurality of types of solid fuels, a plurality of mechanisms for respectively supplying the plurality of types of solid fuels, and the plurality of supplies A mechanism for mixing a plurality of types of solid fuel supplied from the mechanism, a mechanism for crushing the solid fuel mixed by the mixing mechanism, a boiler for burning the solid fuel crushed by the crushing mechanism, and the plurality of types of the above Based on the ash content of each solid fuel and the content of at least one hydrous mineral in the ash, the content of the at least one hydrous mineral in the ash of the entire mixture of the multiple types of solid fuel is A mechanism for determining the mixing ratio of the plurality of types of solid fuels to be equal to or lower than a reference value, and a mixing ratio from the supply mechanism so as to be the mixing ratio of the plurality of types of solid fuels determined by the determination mechanism. Characterized in that it comprises a mechanism for adjusting the plurality of types of solid fuel respectively supply quantity introduced into structure.

  The boiler facility adjusts the mixing ratio of the plurality of types of solid fuel so that the content of the at least one type of hydrous mineral in the ash content of the mixture of the plurality of types of solid fuel is not more than a reference value. Is supplied to the boiler. Therefore, the boiler equipment is easy to operate stably because the furnace heat recovery rate is unlikely to decrease.

Here, the “hydrated mineral” means a mineral containing a water molecule or a hydroxyl group (OH) as a component in the crystal structure and having a dehydration start temperature of 1000 ° C. or less. “Kaolin” is a group of clay minerals and is a generic name for kaolinite, nacrite, and dickite, and means a mineral whose chemical component is represented by Al ₂ Si ₂ O ₅ (OH) ₄ . “Gypsum” means a mineral whose chemical component is represented by CaSO ₄ .2H ₂ O.

  As described above, the boiler operating method and boiler equipment of the present invention can suppress a decrease in furnace heat recovery rate.

It is a key map showing boiler equipment of one embodiment of the present invention. It is a flowchart which shows the procedure of the operating method of the boiler of one Embodiment of this invention. It is a graph which shows the relationship between a kaolin content rate and a furnace heat recovery rate.

  Hereinafter, an embodiment of a boiler operation method and boiler equipment according to the present invention will be described using a thermal power plant.

  The thermal power plant includes the boiler equipment, the steam turbine generator equipment, and the condensate water supply equipment.

<Boiler equipment>
The boiler facility shown in FIG. 1 is a boiler facility that mixes and burns multiple types of solid fuel. The boiler equipment includes a hopper 1, a mixer 2, a pulverizer 3, a boiler 4, a calculator 5, and a supply amount adjusting device 6.

(hopper)
The hopper 1 is a mechanism for supplying solid fuel, and the boiler equipment includes the hopper 1 for supplying a plurality of types of solid fuel. Although FIG. 1 shows a case where two hoppers 1 for supplying two kinds of solid fuels are provided, three or more kinds of solid fuels may be provided. In that case, the boiler equipment includes the same number of hoppers 1 as the type of solid fuel.

  The hopper 1 has a storage tank for storing the solid fuel, and the solid fuel can be dropped and taken out from a bottom-open funnel-shaped mouth at the bottom of the storage tank.

(Mixer)
The mixer 2 is a mechanism for mixing the solid fuel supplied from the hopper 1. As the mixer 2, for example, a known drum mixer or the like can be used.

(Crusher)
The pulverizer 3 is a mechanism for pulverizing the solid fuel mixed in the mixer 2. As the pulverizer 3, a known vertical roller mill or the like can be used.

  The particle size of the solid fuel after pulverization is not particularly limited. For example, the solid fuel can be pulverized so that the proportion of the solid fuel having a particle size of 75 μm or less is 75% or more and 90% or less.

(boiler)
The boiler 4 burns the solid fuel pulverized by the pulverizer 3. The boiler 4 mainly includes a burner 7, a furnace, a heat transfer tube, and a chimney. The boiler 4 burns solid fuel blown together with air in a furnace with a burner 7 and performs heat exchange with a plurality of heat transfer tubes arranged in the vertical direction in the furnace. By this heat exchange, water supplied to the heat transfer tube is heated and pressurized to generate steam. Moreover, the combustion gas generated by the combustion is discharged from the chimney.

  The heat transfer tube is appropriately configured according to the required steam temperature and pressure, for example, a lower heater including a primary heater, a primary reheater, and a economizer disposed in the lower part of the furnace, It can comprise with the upper heat-transfer part provided with the secondary heater, the tertiary heater, the final heater, and the secondary reheater which are arrange | positioned at the furnace upper part. The lower heat transfer section mainly preheats the feed water supplied to the boiler 4, and the upper heat transfer section mainly generates high-temperature and high-pressure steam. In addition, the reheater reheats the steam that has worked in the steam turbine or the like, and creates steam that rotates the reheat cycle turbine. The economizer preheats the feed water of the boiler 4 with the heat of the combustion gas discharged.

(Calculator)
Based on the ash content of each of the plurality of types of solid fuel and the content of kaolin in the ash, the computing unit 5 is based on the content of the kaolin in the ash content of the mixture of the plurality of types of solid fuel. This is a mechanism for determining the mixing ratio of the plurality of types of solid fuels so as to be less than or equal to the value.

  The computing unit 5 calculates the mixing ratio of the plurality of types of solid fuels in the mixing ratio determining step (S2) of the boiler operation method described later. In addition, the calculator 5 controls the supply amount adjusting device 6 based on the calculated mixing ratio.

(Supply amount adjustment device)
The supply amount adjusting device 6 adjusts the supply amount of each of the plurality of types of solid fuel introduced from the hopper 1 to the mixer 2 so that the mixing ratio of the plurality of types of solid fuel determined by the calculator 5 is obtained. It is a mechanism to do. That is, the boiler equipment includes a supply amount adjusting device 6 having the same number as the type of solid fuel, one for each pipe connected to the mixer 2 from the same number of hoppers 1 as the type of solid fuel. The supply amount adjusting device 6 is not particularly limited, and for example, a chain conveyor that conveys solid fuel from the hopper 1 to the mixer 2 can be used. In this case, the supply amount is adjusted by adjusting the moving speed of the conveyor.

<Operation method of boiler>
FIG. 2 shows a boiler operation method using the boiler apparatus. The boiler operation method is a boiler operation method in which a plurality of types of solid fuels are mixed and burned. The operation method of the boiler includes the step (S1) of acquiring the content of ash in the plurality of types of solid fuel and the content of kaolin that is a hydrous mineral in the ash, and the plurality of obtained in the acquisition step. Based on the content of the ash and the content of the kaolin in each of the types of solid fuels, the content of the kaolin in the ash content of the entire mixture of the plurality of types of solid fuel is less than the reference value. A step (S2) of determining a mixing ratio of the solid fuel, and a step (S3) of mixing the plurality of kinds of solid fuels and supplying them to the furnace based on the determined mixing ratio.

  The solid fuel used for the operation method of the boiler is not particularly limited as long as it is a fuel used for the boiler, and examples thereof include coal, sludge carbide, biomass fuel, and the like. Among them, coal that generates a large amount of heat and is preferably used in a thermal power plant or the like is preferable.

  The type of coal is not particularly limited. In the operation method of the boiler, since the mixing ratio of the plurality of types of solid fuels is determined so that the content of the hydrous mineral in the ash is not more than the standard value, the porous shape due to the release of crystal water from the hydrous mineral is determined. Ashes can be prevented. For this reason, even coal containing a relatively large amount of crystal water can be mixed. Examples of coal containing a relatively large amount of crystal water include anthracite, bituminous coal, subbituminous coal, lignite, high silica coal, and high calcium coal.

(Content acquisition process)
In the content acquisition step (S1), the ash content of each of the multiple types of solid fuel and the kaolin content in the ash are acquired.

  Although the measuring method of the content rate of the ash content of each solid fuel is not particularly limited, for example, a measuring method based on JIS-M-8812: 2006 can be used.

  Kaolin is a kind of hydrous mineral, and the kaolin content can be determined by a method of measuring the hydrous mineral content in the ash. Although the measuring method of the content rate of the hydrous mineral in ash is not specifically limited, For example, it can measure using CCSEM (Computer Controlled Scanning Electron Microscopy) analysis. Specifically, in the CCSEM analysis, the mass proportion of the hydrous mineral is quantified by the following procedure. First, a reflected electron image of solid fuel is acquired, and ash particles are recognized by binarization processing. Next, for each recognized particle, the shape such as the length / shortness ratio and the roundness, the equivalent circle diameter calculated from the particle cross-sectional area, and the like are acquired, and the coordinate position of the center of gravity of the particle is recognized. Based on this information, elemental analysis is performed at the center of gravity of each particle, the water-containing mineral is discriminated from the elemental composition ratio, and the mass ratio is quantified. In CCSEM analysis, a series of these processes are automated by software, and a large amount of individual particle data can be acquired in a short time compared to the conventional analysis method for obtaining an average value, so that highly accurate measurement can be performed efficiently. . In this way, the content of hydrous minerals in the ash can be calculated.

  In addition, in the content acquisition step (S1), in addition to the measurement of the ash content, the calorific value of each solid fuel may be measured in advance. By measuring the calorific value of each solid fuel in this way, in the mixing and supplying step (S3) described later, the solid fuel is supplied so that the amount of heat of the mixed solid fuel to be introduced into the boiler becomes a desired amount. Since it is easy to adjust the amount, the boiler can be operated efficiently. Here, the calorific value of the solid fuel can be measured by burning the solid fuel, for example, according to a measurement method based on JIS-M-8814: 2003.

  In order to obtain the ash content, the kaolin content in the ash, the calorific value of the solid fuel, etc., it is necessary to burn the solid fuel in a boiler to generate ash. This combustion is not necessarily performed using an actual can boiler that is actually used, and may be performed, for example, in a combustion test furnace.

  The ash content of each obtained solid fuel, the kaolin content in the ash, the calorific value of the solid fuel, and the like may be recorded and stored as data in, for example, a storage device. By storing the data in this way, the data can be used thereafter. In addition, when using a solid fuel in which the above data is already stored, the acquisition of the ash content, the kaolin content in the ash, the calorific value of the solid fuel, etc. in the content acquisition step (S1) is performed. Measurement can be omitted by using

(Mixing ratio determination process)
In the mixing ratio determination step (S2), the ash content of the mixture of the plurality of types of solid fuels based on the ash content and the kaolin content of each of the types of solid fuel obtained in the acquisition step. The mixing ratio of the plurality of types of solid fuels is determined so that the content of kaolin in the mixture is below the reference value. This step is performed by the calculator 5 of the boiler facility.

Assuming that the ash content of each solid fuel is Ai, the kaolin content in the ash is Ki, and the ratio to the whole fuel is Wi, the kaolin content R in the ash of the entire mixture is expressed by the following formula (1). Can be calculated.

  In the mixing ratio determining step (S2), the mixing ratio of the plurality of types of solid fuels is determined so that the kaolin content R is not more than a reference value. The operation method of the boiler can suppress a decrease in the furnace heat recovery rate by setting the kaolin content R to a reference value or less.

  Here, the reason why the reduction in the furnace heat recovery rate can be suppressed by setting the kaolin content R below the reference value will be described. During boiler operation, the ash content of the burned solid fuel adheres to the furnace wall. The hydrated mineral contained in the ash adhering to the furnace wall releases crystal water in the mineral by the combustion heat of the furnace. The hydrous mineral particles from which crystal water has been released have a porous structure. The ash containing the hydrous mineral in such a porous shape has an extremely low effective thermal conductivity. Therefore, when the content rate of a hydrous mineral becomes high, it is thought that adhering ash becomes a heat insulation layer by the said porous structure, and heat transfer is inhibited, and a furnace heat recovery rate falls. On the other hand, if the content rate of the hydrous mineral is set to the reference value or less, the heat insulating property of the attached ash is reduced, so that it is considered that the decrease in the furnace heat recovery rate can be suppressed. Here, kaolin has a large mass ratio in the hydrous mineral contained in the solid fuel used in the boiler. For this reason, by making the said kaolin content rate R below a reference value, it is easy to obtain the suppression effect of the said furnace furnace heat rate fall.

  Based on the above theory, the present inventor conducted the following test to confirm the optimum reference value of the kaolin content R. First, three types of coal were prepared as solid fuels. Coal was burned using a pulverized coal fired boiler (power generation capacity 700 MW), and the ash content of these three types of coal and the kaolin content in the ash were obtained. In addition, the content rate of the ash content of coal was performed by the measuring method based on JIS-M-8812: 2006. Moreover, the content rate of the kaolin in ash was performed by the method of calculating using CCSEM analysis.

  Next, two or three kinds of these three kinds of coal were used, eight kinds of coal mixing ratios were determined, and the kaolin content R was calculated. Moreover, about 8 types of mixed coal which mixed coal so that it might become this mixing ratio, the actual can boiler was each operated for a fixed period, and the average value of the furnace heat recovery rate in the period was calculated | required.

  Thus, the graph of FIG. 3 which shows the relationship between a kaolin content rate and a furnace heat recovery rate was obtained. The furnace heat recovery rate is represented by a standard value where the furnace heat recovery rate under one condition of the eight types of blended coal is 1, and the larger the value, the higher the furnace heat recovery rate. As can be seen from the graph in FIG. 3, the kaolin content rate and the furnace heat recovery rate are correlated, and it can be seen that the decrease in the furnace heat recovery rate can be suppressed by setting the kaolin content rate to a certain value or less. That is, it can be seen that the mixing ratio of the solid fuel should be determined so that the kaolin content is below the reference value.

  As said reference value, 40 mass% is preferable, 38 mass% is more preferable, 35 mass% is further more preferable, 30 mass% is especially preferable. As can be seen from the graph of FIG. 3, when the reference value is made larger than the above value, the furnace heat recovery rate is excessively lowered, and thus there is a possibility that the decrease in the furnace heat recovery rate cannot be sufficiently suppressed.

(Mixed supply process)
In the mixing and supplying step (S3), the plurality of types of solid fuels are mixed and pulverized based on the mixing rate determined in the mixing rate determining step (S2), and then supplied to the furnace. Specifically, the supply amount adjusting device 6 is controlled by the calculator 5 of the boiler facility, and the amount of solid fuel sent from the hopper 1 to the mixer 2 is adjusted. The mixed solid fuel is pulverized by the pulverizer 3 and then blown into the boiler 4 together with air to be burned.

(advantage)
Since the operation method of the boiler determines the mixing ratio of the plurality of types of solid fuel so that the content of the hydrous mineral is below the reference value, the porous ash caused by the release of crystal water from the hydrous mineral Adhesion can be suppressed. Thereby, since the heat insulation of adhesion ash is reduced, the operation method of the boiler can suppress the fall of the furnace heat recovery rate.

<Steam turbine generator equipment>
The steam turbine generator facility mainly includes a steam turbine and a generator.

  The steam turbine is an external combustion engine that converts steam energy into rotational motion via a turbine (impeller) and a shaft, and is driven by steam generated by the boiler equipment.

  Although the said steam turbine is not specifically limited, For example, it can be comprised with a high temperature high pressure turbine, a high temperature reheat turbine, and a low pressure turbine. In this case, the steam generated in the boiler facility first drives the high-temperature and high-pressure turbine. The steam whose temperature and pressure has been lost due to the driving of the high-temperature and high-pressure turbine is heated again by the reheater of the boiler equipment. The high-temperature reheat turbine is driven by the high-temperature steam heated by the reheater. Further, the steam whose temperature and pressure have been lost due to the driving of the high-temperature reheat turbine is guided to the condensate water supply facility after driving the low-pressure turbine.

  The power of the high-temperature high-pressure turbine, high-temperature reheat turbine, and low-pressure turbine driven by the steam drives the generator to obtain an electrical output.

<Condensate water supply equipment>
The condensate water supply facility mainly includes a condenser, a pump, a heater, and a deaerator.

  The condensate water supply facility cools the steam that drives the steam turbine with a condenser and collects it as condensate. This condensate is pressurized by a pump, heated by a heater, and deaerated by a deaerator. The pressurized and heated condensate is supplied to the economizer of the boiler equipment as feed water for the boiler equipment.

<Advantages>
Since the thermal power plant using the boiler facility uses the operation method of the boiler, the furnace heat recovery rate is unlikely to decrease. For this reason, the thermal power plant using the boiler equipment is easy to operate stably.

[Other Embodiments]
In addition, the operation method and boiler equipment of the boiler of this invention are not limited to the said embodiment.

  In the above embodiment, the method of determining the mixing ratio of a plurality of types of solid fuel based on the content of kaolin as a boiler operation method and boiler equipment has been described, but the content of gypsum in ash and the content of other hydrous minerals The mixing ratio of the solid fuel may be determined based on the rate.

  Moreover, you may determine a mixing ratio based on the content rate of 2 or more types of hydrous minerals as a boiler operating method and boiler equipment. When determining the mixing ratio based on the content of two or more kinds of hydrous minerals, the mixing ratio may be determined so that the sum of the ratios of the hydrous minerals is less than the reference value. You may determine a mixing ratio so that a content rate ratio may become below a reference value. Moreover, when making the content rate of each water-containing mineral below a reference value, the reference value may differ for each water-containing mineral.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

(Solid fuel)
First, three types of coal were prepared as solid fuels. Coal was burned using a pulverized coal fired boiler (power generation capacity 700 MW), and the ash content of these three types of coal and the kaolin content in the ash were obtained. In addition, the content rate of the ash content of coal was performed by the measuring method based on JIS-M-8812: 2006. Moreover, the content rate of the kaolin in ash was computed based on the mass of the kaolin acquired using CCSEM analysis. The results are shown in Table 1.

(No. 1 to No. 7)
Next, among these three types of coal, two or three types of coal were used. 1-No. The mixing ratio of 7 coal was selected, and the kaolin content in the ash was calculated. Moreover, the actual can boiler was operated for a certain period using the coal blended with coal so that the mixing ratio shown in Table 2 was obtained, and the average value of the furnace heat recovery rate within that period was obtained. The results are shown in Table 2.

  In Table 2, the furnace heat recovery rate is No. The value normalized by the furnace heat recovery rate of 2.

  From Table 2, regardless of the type of coal to be mixed, the kaolin content in the ash and the furnace heat recovery rate are highly correlated, and by reducing the kaolin content rate below the reference value, it is possible to suppress a decrease in the furnace heat recovery rate. I understand.

  Moreover, the kaolin content rate in ash is 40% or less. 1-No. No. 6 has a furnace heat recovery rate exceeding 0.95, whereas the kaolin content exceeds 40%. In 7, the furnace heat recovery rate is less than 0.95. From this, it is understood that a high furnace heat recovery rate of 0.95 or more can be obtained by setting the reference value of the kaolin content rate to 40%.

  As described above, the boiler operating method of the present invention can suppress a decrease in the furnace heat recovery rate. Therefore, the boiler equipment using the boiler operation method is easy to operate stably. Moreover, the boiler using the operation method of the said boiler is used suitably for a thermal power plant.

DESCRIPTION OF SYMBOLS 1 Hopper 2 Mixer 3 Crusher 4 Boiler 5 Calculator 6 Supply amount adjusting device 7 Burner

Claims (6)

A method of operating a boiler that mixes and burns multiple types of solid fuel,
Obtaining the ash content in the plurality of types of solid fuel and the content of at least one hydrous mineral in the ash; and
Based on the content of the ash in each of the plurality of types of solid fuel obtained in the acquisition step and the content of the at least one type of hydrous mineral, the at least the ash in the mixture of the plurality of types of solid fuels. And a step of determining a mixing ratio of the plurality of types of solid fuels so that the content of one type of hydrous mineral is equal to or less than a reference value.   The boiler operation method according to claim 1, wherein the at least one hydrous mineral is kaolin or gypsum.   The boiler operating method according to claim 1 or 2, wherein the reference value is 40% by mass.   The method for operating a boiler according to claim 1, wherein the solid fuel is coal.   The operation method of the boiler of any one of Claims 1-4 used for a thermal power plant. A boiler facility that mixes and burns multiple types of solid fuel,
A plurality of mechanisms for supplying the plurality of types of solid fuels;
A mechanism for mixing a plurality of types of solid fuel supplied from the plurality of supply mechanisms;
A mechanism for pulverizing the solid fuel mixed by the mixing mechanism;
A boiler for burning the solid fuel pulverized by the pulverization mechanism;
Based on the ash content of each of the plurality of types of solid fuel and the content of at least one type of hydrous mineral in the ash, the at least one type of hydrous mineral in the ash of the entire mixture of the plurality of types of solid fuel A mechanism for determining the mixing ratio of the plurality of types of solid fuel so that the content of
A mechanism for adjusting the supply amount of each of the plurality of types of solid fuel introduced from the supply mechanism to the mixing mechanism so as to obtain a mixing ratio of the plurality of types of solid fuel determined by the determination mechanism. Boiler equipment.

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