JPH08187484A - Deammonification treatment of coal ash and apparatus therefor - Google Patents

Abstract

PURPOSE: To simply achieve the enhancement of efficiency and the increase of capacity by dividing a process removing ammonia from coal ash into a water dispersing and humidifying process, a degassing process and a kneading process covering the surface of coal ash with water in a membrane form to uniformly wet coal ash. CONSTITUTION: Coal ash having an ammonium salt bonded thereto is humidified at a high speed under a stirring and rotation of 150-1000rpm while water is added to coal ash in an amt. equal to or less than the plastic limit thereof from a humidifier 12, and humidified coal ash is charged in a stagnation hopper 14 to be stagnated while air is supplied and discharged and subsequently kneaded at a high speed under a stirring and rotation of 150-1000rpm by a kneader 28 and this kneaded matter is charged in a separate stagnation hopper 30 to be stagnated while air is supplied and discharged. Generated ammonia is discharged from the stagnation hoppers 14, 30 along with air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coal ash deammonification treatment method and apparatus for efficiently removing ammonia from coal ash having an ammonium salt attached thereto.

[0002]

Exhaust gas generated from a coal-fired boiler contains nitrogen oxides (NOx), and it is necessary to remove this NOx. Conventionally, a system in which ammonia is injected into this exhaust gas to perform denitration treatment and then dust collection is generally adopted. In this system,
At the outlet of the denitration device, there is a leak of several to several tens of ppm of ammonia, which reacts with condensed anhydrous sulfuric acid in the exhaust gas to form ammonium salt and adheres to the ash. This attached ammonium salt is unstable and decomposes depending on temperature, liquid pH, etc.,
Releases ammonia. Therefore, when landfilling coal ash or using it as a cement admixture, the temperature,
Ammonia is generated due to changes in liquid pH, etc., and environmental quality due to odors and product quality deteriorate when used as cement admixture.

Conventionally, the following methods are known as methods for treating ammonium salts attached to coal ash. (1) A method in which 1/4 to 3/4 weight of ash weight water, ammonium salt adhering and lime in an equimolar amount or more of sulfuric anhydride are added, mixed at a low speed, and dried at 100 ° C. or higher (for example, Japanese Patent Publication No. 59- No. 41768). (2) Moisture content of fly ash is about 0.5
A method of adding 10 wt% of water or steam to remove liberated ammonia (see, for example, Japanese Patent Publication No. 60-18473). (3) A method in which an alkaline substance is added to coal ash, and 10 to 30 parts by weight of water is added to 100 parts by weight of coal ash, the mixture is stirred and mixed, and the generated ammonia is returned to the flue (for example, Japanese Patent Publication No.
1-53105). (4) If necessary, coal ash is mixed with alkaline substances such as lime and cement, and is kneaded at high speed with 5 to 20 less water or hot water than the plastic limit, and 90% or more has a particle size of 0.1 mm.
A method of removing ammonia by using a granular material of ˜2 mm and adjusting the pH of the granular material to 11.0 or more (for example,
(See Japanese Patent Publication No. 4-34478).

[0004]

The methods for removing the ammonium salt adhering to the coal ash include the above-mentioned methods, but all of them have low deammonification efficiency, require a large amount of energy, and have complicated treatment processes. Or the processing time becomes long. The present invention has been made in view of the above points, and an object thereof is a step of removing ammonia, a step in which water is uniformly dispersed and humidified in coal ash (water dispersion / humidification step), and a container such as a hopper ( Coal ash deammonification that can easily achieve high efficiency and large capacity by dividing it into a process (degassing process) in which air is supplied and discharged together with ammonia (hereinafter simply referred to as hopper). It is to provide a processing method and apparatus.

Another object of the present invention is to remove the ammonia from the above-mentioned water dispersion / humidification step and deaeration step.
Coal ash deammonification treatment that can achieve higher efficiency and larger capacity easily by uniformly moistening the coal ash by dividing it into a step of covering the surface of the coal ash with water in a thin film (kneading step). A method and apparatus are provided.

[0006] Still another object of the present invention is to provide the ammonia removal step described above in a preceding step of a high-concentration coal ash slurry preparation apparatus so as to meet the environmental regulations of nitrogen content and to have a simple and large capacity. It is an object of the present invention to provide a coal ash deammonification treatment method and apparatus capable of deammonifying coal ash and landfilling. Further, it can be used as a pretreatment operation when it is effectively used as a cement admixture.

[0007]

In order to achieve the above object, the coal ash deammonification treatment apparatus of the present invention, as shown in FIG. 1, comprises coal ash with an ammonium salt attached and an alkaline agent. Mixing / Supplying Mixer / Supplier 10
And a humidifier 12 for stirring and mixing the coal ash / alkaline agent mixture from the mixer / supplier 10 and water, and the humidifier 1
And a retention hopper 14 having an air supply / exhaust mechanism for retaining the humidified coal ash from 2. 1
6 is a conveyor for discharging the humidified deammonified coal ash from the retention hopper 14, 18 is a coal ash hopper, 20 is a coal ash quantitative feeder, 22 is an alkaline agent hopper, 24 is an alkaline agent quantitative feeder, 26 is water or heat A water tank that stores water.

In the apparatus shown in FIG. 1, 150 to 1000 rpm, preferably 250 to 700 rpm is added to coal ash to which ammonium salt adheres while adding water below its plastic limit.
After humidifying at a high speed with the stirring rotation speed of 1, the humidified coal ash is charged and retained in the retention hopper 14, and air is supplied and discharged. Ammonia generated in the retention hopper 14 is discharged from the retention hopper 14 together with the supplied air.
The plasticity limit is the lower limit of the water content which indicates the plasticity of the powder (the powder has an arbitrary shape according to an external force and retains the shape even if the external force is removed). In the humidifier 12, as described above, the humidification is performed at a high speed at a stirring rotation speed of 150 to 1000 rpm, preferably 250 to 700 rpm. 150 to 100, depending on the size of the stirring blade
0 rpm usually corresponds to a peripheral speed of 8 to 50 m / s, and 250 rpm
.About.700 rpm corresponds to a peripheral speed of 13 to 35 m / s. If the stirring rotation speed is less than 150 rpm, the contact state between water and coal ash deteriorates to cause uneven humidification, and the treatment time tends to be long. On the other hand, if it exceeds 1000 rpm, the particles are compacted. As a result, many particles are generated and the power of the humidifier tends to be too large.

In the above method, the amount of water added to the coal ash is 1/10 to 3/4 of the plastic limit, preferably 1/5.
It is preferable to halve it and the residence time in the retention hopper to be 1 to 180 minutes. When the amount of water is less than 1/10 of the plastic limit, the amount of water is too small to uniformly wet the coal ash,
Ammonia desorption tends not to progress, while 3/4
If it exceeds, the ammonia desorbed from the coal ash tends to be dissolved and fixed in water and not desorbed to the gas phase. Further, if the residence time is less than 1 minute, the deammonification efficiency is low, while if it exceeds 180 minutes, the apparatus becomes too large in scale, which causes a cost increase.

Depending on the amount of CaO contained in coal ash, quicklime,
An alkali agent selected from the group consisting of slaked lime, dolomite, cement and waste concrete is preferably added in an amount of 0.1 to 5% by weight with respect to the coal ash so that the alkali content in the coal ash becomes substantially constant. In addition, industrial water, boiler wastewater, desulfurization wastewater or seawater can be used as the added water. In this case, depending on the amount of CaO contained in the coal ash, 50-
It is more effective to use hot water adjusted to 98 ° C.

When the highly efficient deammonification is not necessary due to the environmental regulation value, or when the ash discharged does not contain much ammonia, the water dispersion step + hopper, etc. as shown in FIG. Since it is possible to sufficiently deal with the retention of, the kneading step can be omitted, and the cost can be significantly reduced. Moreover, since the deammonification rate varies depending on the amount of CaO in the coal ash, a mechanism that can adjust the amount of alkaline agent supplied and the temperature of the supplied water should be provided according to the amount of CaO in the ash of the coal used in the boiler. This enables highly efficient deammonification treatment of any type of coal ash. There is a correlation between the coal type and the CaO amount in the coal ash, and if the coal type is known, the CaO amount in the coal ash can be estimated. When the amount of CaO in the coal ash is small, the amount of alkali agent to be added is controlled to increase and the temperature of water to be added is controlled to increase. In addition, when the amount of the alkaline agent added is increased, the treated ash after humidification is likely to solidify, and it has an excellent feature of being used as a landfill at the time of landfill.

FIG. 2 shows another example of the device of the present invention. The apparatus of this example mixes and supplies a coal ash with an ammonium salt attached thereto and an alkaline agent, and agitates and mixes the coal ash / alkaline agent mixture from this mixer 10 and water. A humidifier 12, a retention hopper 14 having an air supply / discharge mechanism for retaining the humidified coal ash from the humidifier 12, and a kneader 28 for kneading the humidified coal ash from the retention hopper 14. A retention hopper 30 having an air supply / exhaust mechanism for retaining the kneaded material from the kneader 28. 32 is a stirring blade, 34
Is a conveyor for discharging the deammonified kneaded material from the retention hopper 30.

In the apparatus shown in FIG. 2, 150 to 1000 rpm, preferably 250 to 700 rpm is added to coal ash to which ammonium salt adheres while adding water below its plastic limit.
After humidifying at high speed with the stirring rotation speed of 1, the humidified coal ash is fed into and retained in the retention hopper 14, air is supplied and discharged, and then the humidified coal ash from the retention hopper 14 is discharged to 15 times.
After high-speed kneading at a stirring rotation speed of 0 to 1000 rpm, preferably 250 to 700 rpm, the kneaded material is introduced into and retained in another retention hopper 30, and air is supplied and discharged. Ammonia generated in the retention hoppers 14 and 30 is
It is discharged from the stay hoppers 14 and 30 together with the supplied air. The stirring rotation speed in the kneader 28 is 150 rpm
When the peripheral speed is less than 8 m 2 / s, the kneading power is insufficient and the surface of ash is not uniformly wetted, so that the deammonification efficiency tends to decrease, while 1000 rpm (usually,
When the peripheral speed exceeds 50 m 2 / s 2), the kneading force becomes too strong and the ash particles aggregate to form a granular body, so that the deammonification efficiency tends to decrease. Other configurations and operations are similar to those in the case of FIG.

FIG. 3 shows another example of the device of the present invention. The apparatus of this example mixes and supplies a coal ash with an ammonium salt attached thereto and an alkaline agent, and agitates and mixes the coal ash / alkaline agent mixture from this mixer 10 and water. A humidifier 12, a retention hopper 14 having an air supply / exhaust mechanism for retaining the humidified coal ash from the humidifier 12, and water added to the humidified coal ash from the retention hopper 14 with stirring to mix the coal. Slurry preparing apparatus 36 for preparing ash slurry, and this slurry preparing apparatus 36
And a slurry transport pipe 40 equipped with a high-pressure slurry pump 38 for pipe-transporting the coal ash slurry from

In the apparatus shown in FIG. 3, 150 to 1000 rpm, preferably 250 to 700 rpm is added to coal ash to which ammonium salt is attached while adding water below its plastic limit.
After high-speed humidification at a stirring rotation speed of 1, the humidified coal ash is charged and retained in the retention hopper 14, air is supplied and discharged, and then the liquid limit of the coal ash is 1.05 to 1.6.
Water is added to 0, preferably 1.10 to 1.40, 150 to 1000 rpm, preferably 250 to 700 rpm
High-speed kneading is carried out at a stirring rotation speed of 1 to produce a coal ash slurry, and this coal ash slurry is pipe-transported to the ash disposal site. The liquid limit refers to the upper limit of the water content at which the powder exhibits plasticity (the powder takes an arbitrary shape according to an external force and retains that shape even if the external force is removed). A powder containing more than the limit of water exhibits fluidity. The amount of water added is 1.0, which is the liquid limit
If it is less than 5, the fluidity of the slurry is insufficient and it cannot be transported by the slurry pump, or the power of the slurry pump tends to be very large, while if it exceeds 1.60, the concentration of the slurry is high. Is too low, transport efficiency is reduced, and landfill density tends to be low. If the stirring speed in the slurry preparation device 36 is less than 150 rpm (usually, the peripheral speed is 8 m 2 / s 2), the mixing will be insufficient and a homogeneous slurry will not be obtained. On the other hand, 100
When the speed exceeds 0 rpm (normally, the peripheral speed is 50 m / s), the power becomes too large, which causes a cost increase.
The life of the slurry preparation device tends to be short. Other configurations and operations are similar to those in the case of FIG.

FIG. 4 shows still another example of the device of the present invention. The apparatus of this example is a mixing / supplying machine 10 for mixing / supplying coal ash to which ammonium salt is attached and an alkaline agent.
And a humidifier 12 for stirring and mixing the coal ash / alkaline agent mixture from the mixer / supplier 10 and water, and the humidifier 1
2, a retention hopper 14 having an air supply / exhaust mechanism for retaining the humidified coal ash, a kneader 28 for kneading the humidified coal ash from the retention hopper 14, and a kneader 28
A retention hopper 30 having an air supply / exhaust mechanism for retaining the kneaded material from S., and a slurry preparation device 36 for preparing coal ash slurry by adding water to the humidified coal ash from the retention hopper 30 and stirring and mixing. This slurry preparation device 36
And a slurry transport pipe 40 equipped with a high-pressure slurry pump 38 for pipe-transporting the coal ash slurry from

In the apparatus shown in FIG. 4, 150 to 1000 rpm, preferably 250 to 700 rpm is added to coal ash to which ammonium salt adheres while adding water below its plastic limit.
After high-speed humidification at the stirring rotation speed of 1, the humidified coal ash is fed into and retained in the retention hopper, air is supplied and discharged, and then the humidified coal ash from the retention hopper is fed to 150 to 1
After kneading at a high speed of 000 rpm, preferably 250 to 700 rpm, the kneaded material is charged and retained in another retention hopper, and air is supplied and discharged, and then the liquid limit of coal ash is 1. 05-1.60, preferably 1.10-1.40, with water added to 150-1
High-speed kneading is carried out at a stirring rotation speed of 000 rpm, preferably 250 to 700 rpm to obtain a coal ash slurry, and the coal ash slurry is pipe-transported to an abandoned land. Other configurations and operations are similar to those in the case of FIGS.

[0018]

The present invention will be described in more detail based on the following examples and comparative examples. However, the present invention is not limited to the following examples, and can be appropriately modified and carried out. Is. In Examples and Comparative Examples of the present invention, coal ash (A) and (B) having the properties shown in Table 1 were used. The pH measurement of the coal ash elution water was carried out by the landfill disposal method (ash / water = 10%, shaking time = 6 hours) of Notification 13 of the Environment Agency. The plastic limit was measured according to JIS A 1206 (Plastic limit test method for soil). Ammonia was measured immediately after kneading on a wet basis and is indicated on a dry basis.

[0019]

[Table 1]

Example 1 30 kg of coal ash (A) was mixed with 3 kg of industrial water in a continuous humidifier (coal ash residence time of 1 second or less) with a stirring speed of 400 rpm.
The mixture was mixed with (1/3 of the plastic limit), put into a retention hopper, and the retention time was set to 5 minutes. During this period, air was supplied and discharged. Residual NH _{4 of} ash taken out from the retention hopper
The amount was 10 mg / kg.

Example 2 0.3 kg of slaked lime was added to 30 kg of coal ash (B) to give a pH of 11.
After adjusting to 2, it was mixed with 3 kg of industrial water (about 3/10 of the plastic limit) with a continuous humidifier (coal ash retention time of 1 second or less) with a stirring speed of 400 rpm, and the mixture was put in a retention hopper to set the retention time. 5 minutes. During this period, air was supplied and discharged. The amount of residual NH _{4 in} the ash taken out from the hopper was 11
It was mg / kg.

Example 3 After adding 0.3 kg of slaked lime to 30 kg of coal ash (B), a continuous humidifier having a stirring speed of 400 rpm (retention time of coal ash 1
(Less than a second), mixed with 3 kg of industrial water, put in a retention hopper,
The residence time was 5 minutes. During this period, air was supplied and discharged. The humidified coal ash taken out from the hopper was further kneaded at high speed at a stirring speed of 600 rpm for 1 minute, and then retained in the retention hopper for 5 minutes, during which air was supplied and discharged. The amount of residual NH _{4 in the} ash was 7 mg / kg.

Example 4 After adding 0.3 kg of slaked lime to 30 kg of coal ash (B), a continuous humidifier having a stirring speed of 400 rpm (retention time of coal ash 1
(Less than a second), mixed with 3 kg of industrial water, put in a retention hopper,
The residence time was 5 minutes. During this period, air was supplied and discharged. After that, add 10.5 kg of water to the humidified coal ash taken out from the hopper so that the liquid limit becomes 1.30 times.
In addition, a 67% concentrated slurry was produced. The amount of residual NH ₄ in the high-concentration slurry was 7 mg / kg based on dry ash.

Example 5 After adding 0.3 kg of slaked lime to 30 kg of coal ash (B), a continuous humidifier having a stirring speed of 400 rpm (retention time of coal ash 1
(3 seconds or less) was mixed with 3 kg of seawater, and the mixture was put into a retention hopper and the retention time was set to 5 minutes. During this period, air was supplied and discharged. The amount of residual NH _{4 in} the ash taken out from the hopper is 1
It was 4 mg / kg.

Example 6 After adding 0.3 kg of slaked lime to 30 kg of coal ash (B), a continuous humidifier having a stirring speed of 400 rpm (retention time of coal ash 1
(2 seconds or less) was mixed with 3 kg of industrial water at 95 ° C., put in a retention hopper, and the retention time was 5 minutes. During this period, air was supplied and discharged. The amount of residual NH _{4 in} the ash taken out from the hopper was 9 mg / kg.

Comparative Example 1 30 kg of coal ash (A) was charged into a kneader having a stirring speed of 100 rpm, and 3 kg of industrial water was charged for 30 seconds while stirring.
Mix for an additional 3 minutes. The amount of residual NH _{4 in the} ash was 25 mg / kg.

Comparative Example 2 After adding 0.3 kg of slaked lime to 30 kg of coal ash (B) and mixing for 1 minute with a kneader at a stirring speed of 100 rpm, 3 kg of industrial water was added for 30 seconds while stirring, and further, Mix for 3 minutes. The residual NH ₄ content of the ash was 22 mg / kg.

Comparative Example 3 30 kg of coal ash (A) was charged into a kneader having a stirring speed of 400 rpm, and 3 kg of industrial water was charged for 30 seconds while stirring.
Mix for an additional 3 minutes. 20 mg / kg of residual NH _{4 in} ash
Met.

Comparative Example 4 After adding 0.3 kg of slaked lime to 30 kg of coal ash (B) and mixing for 1 minute with a kneader at a stirring speed of 400 rpm, 3 kg of industrial water was added for 30 seconds while stirring, and Mix for 3 minutes. The amount of residual NH _{4 in the} ash was 18 mg / kg.

Comparative Example 5 Coal ash (A) (30 kg) was mixed with industrial water (3 kg) by a continuous humidifier having a stirring speed of 100 rpm, and the mixture was put into a retention hopper to have a retention time of 5 minutes. During this period, air was supplied and discharged. The amount of residual NH _{4 in} the ash taken out from the retention hopper was 23 mg / kg.

Comparative Example 6 To 30 kg of coal ash (B), 0.3 kg of slaked lime was added, and mixed with 3 kg of industrial water in a continuous humidifier having a stirring speed of 100 rpm,
It was placed in a retention hopper and the retention time was 5 minutes. During this period, air was supplied and discharged. The amount of residual NH _{4 in} the ash taken out from the hopper was 20 mg / kg.

[0032]

Since the present invention is configured as described above, it has the following effects. (1) Since the ammonia removal process is divided into a water dispersion / humidification process and a deaeration process by the retention hopper, even if the processing amount increases due to scale-up, it can be controlled by the retention time in the retention hopper. it can. Therefore, the deammonification rate does not decrease so much. Further, even if the ash processing amount increases, it can be dealt with by increasing the retention hopper capacity, and the device cost can be suppressed. (2) When the steps are divided into the water dispersion / humidification step and the deaeration step in the first step and the kneading step in the second step, the first step is to uniformly disperse the ash in water and the second step is to improve the wettability of ash. The ash can be uniformly wetted as a whole. Therefore, the deammonification efficiency can be improved, and a decrease in the deammonification rate during scale-up can be significantly suppressed. Further, even if the regulation of nitrogen content in the closed water area is strengthened, it is possible to carry out deammonification until it can sufficiently cope with it. (3) When combined with a high-concentration slurry ashing facility, it is possible to easily trash and landfill in a large capacity that complies with nitrogen content environmental regulations. (4) As landfill density increases, solidification is promoted,
It becomes easier to use the site. In addition, if it is used for pretreatment when it is effectively used as a cement admixture, etc., it can be promoted for use.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of a coal ash deammonification treatment apparatus of the present invention.

FIG. 2 is a system diagram showing another embodiment of the device of the present invention.

FIG. 3 is a system diagram showing another embodiment of the device of the present invention.

FIG. 4 is a system diagram showing still another embodiment of the device of the present invention.

[Explanation of symbols]

 10 Mixing / Supplying Machine 12 Humidifier 14 Retention Hopper 16 Conveyor 28 Kneader 30 Retention Hopper 34 Conveyor 36 Slurry Preparation Device 38 High Pressure Slurry Pump 40 Slurry Transport Pipe

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical display location B09B 5/00 ZAB N (72) Inventor Yukio Kubo 1-1 Kawasaki-cho, Akashi-shi, Hyogo Kawasaki Heavy Industries Akashi Plant Co., Ltd. (72) Inventor Tamotsu Nakagawa 2-11-1, Minamisuna, Koto-ku, Tokyo Kawasaki Heavy Industries Ltd. Tokyo Design Office

Claims (12)

[Claims] 1. A coal ash to which an ammonium salt adheres is moistened at a high speed at a stirring rotation speed of 150 to 1000 rpm while adding water below its plasticity limit, and then the moisturized coal ash is introduced into and retained in a retention hopper and air. A method for deammonification of coal ash characterized by supplying and discharging. 2. The coal ash to which the ammonium salt adheres is moistened at a high speed at a stirring rotational speed of 150 to 1000 rpm while adding water below its plasticity limit, and then the moisturized coal ash is added to and retained in a retention hopper and air is also added. Supply and discharge
Then, the humidified coal ash from the retention hopper is added to 150 to 100.
A method for deammonification of coal ash, characterized in that after kneading at a high rotation speed of 0 rpm, the kneaded material is charged / retained in another retention hopper and air is supplied / discharged. 3. The coal ash to which the ammonium salt adheres is moistened at high speed at a stirring rotation speed of 150 to 1000 rpm while adding water below its plasticity limit, and then the moisturized coal ash is added to and retained in a retention hopper and air is also added. Supply and discharge
Then, water is added so that the liquid limit of coal ash becomes 1.05 to 1.60, and the mixture is kneaded at a high speed at a stirring rotation speed of 150 to 1000 rpm to obtain a coal ash slurry. A method for deammonification of coal ash characterized by transporting. 4. The coal ash to which the ammonium salt adheres is moistened at high speed at a stirring rotation speed of 150 to 1000 rpm while adding water below its plasticity limit, and then the moisturized coal ash is introduced into and retained in a retention hopper and air is added. Supply and discharge
Then, the humidified coal ash from the retention hopper is added to 150 to 100.
After high-speed kneading at a stirring rotation speed of 0 rpm, this kneaded material is charged and retained in another retention hopper, air is supplied and discharged, and then the liquid limit of coal ash of 1.05-1.
A coal ash deammonification treatment method comprising adding water to 60 to knead the mixture at a high rotation speed of 150 to 1000 rpm to obtain a coal ash slurry, and pipe transport the coal ash slurry to an ash dump. 5. The amount of water added to the coal ash is 1 / the plastic limit.
10 to 3/4, retention time in the retention hopper is 1 to 1
It is 80 minutes, The coal ash deammonification processing method in any one of Claims 1-4. 6. An alkali agent selected from the group consisting of quick lime, slaked lime, dolomite, cement and waste concrete is added to the coal ash according to the amount of CaO contained in the coal ash so that the alkali content in the coal ash becomes substantially constant. The coal ash deammonification treatment method according to any one of claims 1 to 5, wherein 0.1 to 5% by weight is added to the ash. 7. The method for treating coal ash deammonification according to claim 1, wherein industrial water, boiler wastewater, desulfurization wastewater or seawater is used as the added water. 8. Depending on the amount of CaO contained in the coal ash, 50 to
The coal ash deammonification treatment method according to claim 7, wherein hot water adjusted to 98 ° C is used. 9. A mixing / supplying machine for mixing / supplying coal ash with an ammonium salt attached thereto and an alkali agent, and a humidifier for stirring and mixing the coal ash / alkali agent mixture from this mixing / supplying machine and water. A coal ash deammonification treatment apparatus comprising: a retention hopper having an air supply / discharge mechanism for retaining the humidified coal ash from the humidifier. 10. A mixing / supplying machine for mixing / supplying coal ash with an ammonium salt attached thereto and an alkaline agent, and a humidifier for stirring and mixing the coal ash / alkaline agent mixture from this mixing / supplying machine and water. , A staying hopper equipped with an air supply / exhaust mechanism for holding the humidified coal ash from the humidifier, a kneader for kneading the humidified coal ash from the staying hopper, and a kneaded material from the kneader A coal ash deammonification treatment apparatus comprising: a retention hopper equipped with an air supply / exhaust mechanism. 11. A mixing / supplying machine for mixing / supplying coal ash with an ammonium salt attached thereto and an alkali agent, and a humidifier for stirring and mixing the coal ash / alkali agent mixture from this mixing / supplying machine and water. A slurry hopper that retains the humidified coal ash from the humidifier and has a retention hopper equipped with an air supply / discharge mechanism, and water is added to the humidified coal ash from the retention hopper to stir and mix to prepare a slurry of coal ash. A coal ash deammonification treatment device comprising: a device; and a slurry transportation pipe equipped with a high-pressure slurry pump, for pipe-transporting the coal ash slurry from the slurry preparation device. 12. A mixing / supplying machine for mixing / supplying coal ash with an ammonium salt attached thereto and an alkali agent, and a humidifier for stirring / mixing the coal ash / alkali agent mixture from this mixing / supplying machine and water. , A staying hopper equipped with an air supply / exhaust mechanism for holding the humidified coal ash from the humidifier, a kneader for kneading the humidified coal ash from the staying hopper, and a kneaded material from the kneader A hopper provided with an air supply / exhaust mechanism, a slurry preparation device that prepares a coal ash slurry by adding water to the humidified coal ash from the retention hopper, and stirring and mixing, and a coal ash from this slurry preparation device. A coal ash deammonification treatment apparatus, comprising: a slurry transportation pipe equipped with a high-pressure slurry pump, for transporting the slurry by pipe.