JP2002114548A - Method for estimating property of coal ash and method for producing artificial lightweight aggregate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To grasp the properties of coal ash without analyzing the coal ash so that it becomes possible to start treatment immediately after the coal ash is received. SOLUTION: The method for estimating the properties of coal ash is an estimation method for estimating the properties of coal ash formed by combusting a mixed coal comprising plural kinds of coals having different compositions with an another. The properties of the coal ash are estimated according to property estimation formula: the property of the coal ash = Σ[S(i).M(i)]/ΣM(i)+α, where S(i) is the property of i-th coal of plural kinds of coals used in the mixed coal; M(i) is the use amount of i-th coal of plural kinds of coals; (α) is a correction value which is a difference between the theoretical average value of the coal ash properties calculated from the coal property of each kind of coal used in various kinds of mixed coals and the analytical average value of the coal ash properties obtained by analyzing coal ash formed by combusting various kinds of mixed coals.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for predicting the properties of coal ash produced by burning a coal blend and a method for producing an artificial lightweight aggregate.

[0002]

2. Description of the Related Art As one of effective techniques for utilizing coal ash discharged from a coal-fired boiler, there is an artificial lightweight aggregate applied to aggregate of lightweight concrete. The artificial lightweight aggregate using this coal ash is specified in JIS-A5002. For example, the absolute dry specific gravity, which is an index of weight reduction, is 1.0 to 1.0 for M class.
It is set to 1.5.

[0003] Therefore, conventionally, when producing artificial lightweight aggregates from coal ash, if the properties of the composition and melting temperature of the coal ash are unknown when the coal ash is received from a power plant or the like, Analyze the properties of coal ash, and determine the granulation and firing conditions that will result in artificial lightweight aggregate within the standard based on the analysis results. Then, the coal ash is classified into a coarse powder containing fine particles having a predetermined particle diameter, and the coarse powder is granulated and fired under the above-described granulation and firing conditions, thereby producing an artificial lightweight aggregate that conforms to the standard. are doing.

[0004]

However, as described above, in the conventional manufacturing method in which the coal ash is subjected to analysis such as classification or granulation after the coal ash is received and analyzed. Since a waiting time of up to several days occurs until the analysis result is obtained, the processing cannot be started immediately after acceptance. Therefore, it is necessary to store coal ash in large silos corresponding to the maximum waiting time so that production is not interrupted by the waiting time for analysis.

Further, when several types of coal are mixed and mixed (coal blended) in about one to two weeks as in a domestic power plant, the properties of coal ash also change with each change in coal blend. Therefore, it is necessary to introduce a plurality of large silos as described above so that coal ash having different properties are not mixed. As a result, in the conventional method, a large site for introducing a plurality of large silos is required, and the facility cost of the silo itself increases.

[0006] Such a problem occurs not only in the case of producing artificial lightweight aggregate, but also in the case of producing cement or the like using coal ash.

Accordingly, the present invention provides a method for predicting the properties of coal ash, which allows the properties of coal ash to be ascertained without analyzing the coal ash so that the treatment can be started immediately after receiving the coal ash. And a method for producing an artificial lightweight aggregate to which the property prediction method is applied.

[0008]

Means for Solving the Problems In order to solve the above problems, the invention of claim 1 predicts the properties of coal ash generated by burning a coal mixture composed of a plurality of types of coal having different compositions. Coal ash properties prediction method,
The coal properties of the i-th coal among the plurality of types used for the coal blend are S (i), and the usage amount of the i-th coal among the plurality of types is M (i). The theoretical average value of the coal ash properties obtained from the coal properties of each variety,
Coal ash property = Σ [S (i) · M (when the difference from the analysis average value of the coal ash property obtained by analyzing the coal ash generated by burning the above various types of coal is a correction value α) i)] / ΣM (i) +
The coal ash property is predicted based on a property prediction formula represented by a correction value α 2.

According to the above configuration, the actual coal ash properties of the coal ash can be grasped in a shorter time than in the case of analysis based on the property prediction formula. As a result, the production can be started immediately after receiving the coal ash and the production conditions can be determined. Therefore, it is not necessary to provide a large number of large silos in a production facility for artificial lightweight aggregate, cement, or the like. As a result, the site area of the silo can be reduced, and the facility cost of the silo itself can be reduced.

According to a second aspect of the present invention, there is provided the method for predicting the properties of coal ash according to the first aspect, wherein the coal properties include Si.
O ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , CaO, Na ₂ O, K
_It consists of a composition (%) composed of ₂ O, MgO and SO ₃ and a melting temperature (° C.). The correction value α is 0.71 for SiO ₂ , 3.05 for Al ₂ O ₃ , and Fe ₂ O ₃ Is 0.3
1, CaO is -0.29, Na ₂ O is 0.23, K ₂ O
Is 0.29, MgO is 0.02, SO ₃ is 0.71, and the melting temperature (° C.) is −43. According to the above configuration, the coal ash properties obtained by the property prediction formula can be made very close to the actual coal ash properties.

[0013] The invention of claim 3 is a method of manufacturing an artificial lightweight aggregate, which is based on the coal ash property obtained by the method for predicting the property of coal ash according to claim 1 or 2, and is within the standard. After the granulation and firing conditions are determined, the coal ash is classified into a coarse powder containing fine particles having a predetermined particle size, and the coarse powder is granulated and fired under the granulation and firing conditions to produce an artificial lightweight bone. It is characterized by using wood. According to the above configuration, an artificial lightweight aggregate can be manufactured immediately after receiving coal ash. Further, since the silo can be reduced in size, the manufacturing cost can be reduced.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention is shown in FIG.
This will be described below based on FIG. Stone according to the present embodiment
As shown in Fig. 1, the method for predicting the properties of coal ash
Coal-fired power plants, etc. that use multiple types of coal up to X types
Applies to coal ash discharged from burning facilities. Concrete
In general, facilities such as power plants have multiple types from Type A to Type X.
It consists of multiple pits 51 that store several types of coal individually.
A coal yard 52 is provided. Note that each pit 51
The coal contained is SiO_Two, Al_TwoO _Three, Fe_TwoO
_Three, CaO, Na_TwoO, K_TwoO, MgO and SO_ThreeOr
The coal properties of the composition and melting temperature of each component (%)
Analysis is required.

In the above-mentioned coal yard 52, each pit 51
Is provided with a charging device (not shown) capable of charging coal of a predetermined amount a to x. A boiler 53 is provided at the subsequent stage of the charging device.
Ｘx are burned while mixing the varieties A〜X of coal. An exhaust port of the boiler 53 has an air heater (AH) 54, a dust collector 55 for collecting coal ash, and a desulfurization / denitration facility for desulfurizing and denitrifying the exhaust gas from which the coal ash has been removed by the dust collector 55. 56 and a chimney 57 for dispersing the exhaust gas into the atmosphere are provided in this order. Note that the desulfurization / denitration equipment 56 may be provided in a stage preceding the air heater (AH) 54.

A cement related facility 58 and an artificial lightweight aggregate manufacturing plant 59 are provided downstream of the dust collector 55. These facilities 58 and 59 are provided with a dust collector 5.
The cement ash and artificial lightweight aggregate are manufactured using the coal ash collected in step 5 as a raw material. In the case of the cement-related facility 58, coal ash obtained from the boiler 53 or the air heater 54 is also used.

The coal combustion facility configured as described above is
It is monitored by a monitoring device 60 composed of an information processing device. The monitoring device 60 provides information on the amount of coal stored in each pit 51 of the coal yard 52, the lot number, the date and time of receipt, the coal information such as the properties of the coal, and the boiler 53 from each pit 51.
A recording unit for recording the input amounts a to x of the coals charged to the boiler, the operating status of each device such as the boiler 53, and the like, and calculating the properties of the coal ash as coal ash property data based on the following property prediction formula: And a communication unit for transmitting coal ash property data to the cement-related facility 58 and the artificial lightweight aggregate manufacturing plant 59.

Here, the property prediction formula is based on the property of coal ash = (A
Coal properties of varieties x input amount a + Coal properties of varieties x input amount
b + ... + Coal properties of X type × input amount x) ÷ (input amount
a + input amount b +... + input amount x) + correction value α
You. That is, the property prediction formula is based on the property of coal ash = Σ [S (i) ·
M (i)] / ΣM (i) + correction value α. Note that S
(I) is the i-th of multiple varieties used for coal blending
M (i) is the coal properties of coal,
It is the usage of the i-th coal. The correction value α will be described later.
Properties of each type of coal used in various coal blends
The theoretical average value of coal ash properties obtained from
Ash determined by analyzing coal ash generated by burning coal
This is the difference from the analytical average of the properties, and the composition (%) and
And the melting temperature (° C.). concrete
Contains SiO_TwoIs 0.71, Al _TwoO_ThreeIs 3.05, F
e_TwoO_Three0.31, CaO is -0.29, Na_TwoO
0.23, K_TwoO: 0.29, MgO: 0.02, SO
_ThreeIs 0.71 and the melting temperature (° C.) is −43, and the correction value α
Is set.

The artificial lightweight aggregate manufacturing plant 59 to which the coal ash property data is transmitted from the monitoring device 60 and the coal ash is supplied from the dust collector 55, as shown in FIG. A pit 61 is provided. These pits 61 are switched each time the coal mixture fed into the boiler 53 in FIG. 1 is changed, and individually store coal ash having different properties. In addition, the artificial lightweight aggregate manufacturing plant 59
Includes a control device (not shown). Before starting the production using the coal ash of each pit 61, the control device obtains the granulation and firing conditions so that the desired artificial lightweight aggregate is produced based on the coal ash property data of the coal ash. The processing operation of the manufacturing plant 59 is controlled under the conditions.

A classifier 11 for classifying coal ash by air sorting is provided downstream of the pit 61 described above. The classifier 11 is provided with a rotating body that rotates each particle of the coal ash to give a centrifugal force due to the rotational flow and a drag force due to the air flow to each particle, and blows the coarse particles toward the outer periphery of the rotating body by the centrifugal force. By sending the fine particles together with air in the inner circumferential direction of the rotating body, both particles are selected. The classifier 11 includes a coarse powder in which the weight ratio of the fine particles having a particle size of 10 μm or less in the coal ash is a predetermined value or less;
The rotation speed and size of the rotating body are set so as to classify the rotating body into other fine powder.

Here, when classifying coal ash, a particle size of 10
The reason for paying attention to the fine particles having a particle size of μm or less is that if there are many fine powders in the coarse powder, the fine powder enters between the coarse powders and fills the voids. Also, the amount of fine powder having a particle size of 10 μm or less greatly affects the absolute specific gravity, and even if the amount of fine powder having a particle size of more than 10 μm is specified, the absolute dry specific gravity does not change so much.
Furthermore, the classification efficiency when classifying coal ash is 10 μm in particle size.
If the ratio exceeds the limit, the efficiency of collecting the coarse powder is reduced, and the fine powder and the coarse powder cannot be separated. Especially in the case of coal ash, the fine powder is J
Since it can be sold as IS ash, it is necessary to separate fine particles having a particle size of 10 μm or less in order to set the selection ratio between coarse powder and fine powder within 50% ± 20%.

Classifier 11 for classifying coal ash as described above
The outlet 11a for coarse powder containing fine particles is connected to the first hopper 1 of the pellet forming system 43. The pellet forming system 43 includes first to fourth hoppers 1 to 4, a kneader 5, a crusher 6, a belt feeder 7, and a bread granulator 8 in this order from the upstream side. The first hopper 1 is a classifier 1
The coal ash sent from 1 is temporarily stored. The second to fourth hoppers 2 to 4 are provided side by side with the first hopper 1. These hoppers 2 to 4 respectively contain a low specific gravity agent, a foaming agent, and pulverized coal as fillers.
In addition, a filler means the material which reduces absolute dry specific gravity. The first to fourth hoppers 1 to 4 have supply ports at their lower ends connected to each other, and mix coal ash, a low specific gravity agent, a foaming agent, and pulverized coal at an arbitrary ratio. The mixture can be supplied to the kneading machine 5 at the subsequent stage.

Here, as the low specific gravity agent, a substance whose true specific gravity or apparent specific gravity is lighter than that of coal ash as a main raw material or any substance containing a component which burns and burns down can be used. Common low-specific-gravity agents include chaff, sawdust, chute, bacass, coal grains, coke grains, charcoal grains, wood chips, and crushed paper. In addition, the low specific gravity agent is a fluid bed boiler ash or sewage sludge incineration ash, construction mud, It is preferable to effectively use any one or more of heavy oil ash that contains residual carbon.

Sewage sludge incineration ash is a residue generated when burning sludge generated in a sewage treatment plant. Construction mud is waste mainly composed of earth and sand generated in construction and civil engineering work. is there. Fluidized bed boiler ash is a residue of coal burned in the fluidized bed boiler ash, and heavy oil ash is a residue generated when burning heavy oil. In particular, fluidized-bed boiler ash alone is not a lightweight aggregate and has more residual carbon than coal ash, so it is suitable for mixing with coal ash to lower the absolute dry specific gravity. However, waste-based low-specific-gravity agents such as fluidized-bed boiler ash mixed with 100 parts by weight of coal ash are mixed up to 40 parts by weight. If the amount exceeds 40 parts by weight, the yield rate at the time of firing is deteriorated due to the decrease in crushing strength, and the decrease in the absolute specific gravity is reduced.

As the foaming agent, at least one of foamable minerals such as perlite, shirasu, and zeolite and gypsum can be used. Shirasu, perlite and zeolite are naturally occurring minerals, and gypsum may be any of industrial products or those generated in a desulfurization process. The foaming agent is not limited to the above-mentioned materials, and may be any material that exhibits foaming properties in a high temperature range of 800 ° C. or higher. However, the amount of the foaming agent mixed with the coal ash is limited to 20 parts by weight with respect to 100 parts by weight of the coal ash or the coal ash and the low specific gravity agent. This is because even when the amount exceeds 20 parts by weight, a decrease in the absolute specific gravity is not observed.

A kneader 5 is disposed downstream of the first to fourth hoppers 1 to 4 containing various additives and coal ash as described above. The kneading machine 5 is configured to add water 5 ′ to a mixture of coal ash or coal ash and pulverized coal, or at least one of coal ash and pulverized coal and / or a low specific gravity agent and a foaming agent, and knead the mixture. ing. And kneading machine 5
Is connected to a crusher 6 for crushing the mixture, and the crusher 6 is connected to a bread granulator 8 via a belt feeder 7. The bread granulator 8 is set so as to form the mixture from the crusher 6 as raw pellets 65 having a predetermined particle size.

The above-mentioned pan type granulator 8 is connected to a self-combustion type linear moving sintering machine 12 using a grate.
The linear moving firing machine 12 is configured to sinter the raw pellets 65 supplied from the bread granulator 8 by performing a drying-ignition-firing-cooling process in a continuous operation.

That is, the firing machine 12 comprises an endless grate 21 which moves in the horizontal direction (arrow A in the figure), and this grate 21
Of the drying / preheating furnace 22, the ignition furnace 23 and the sintering / heat preserving furnace 24, the hot air tube 28 for feeding high-temperature air to each furnace 22, 23/24, and the sintering / heat preserving furnace 24. And a cooling zone 29 provided on the downstream side. Below the grate 21, a wind box 25 having an upper end opened toward the grate 21 is provided. The lower end of the wind box 25 is connected to a suction side of a blower 27 through an exhaust duct 26. ing. And
A chute 30 for leading out a sintered body of the raw pellets 65 generated by the firing machine 12 and a crusher 31 for separating the sintered body are provided downstream of the linear moving firing machine 12 configured as described above. And a sieving machine 32 for sifting the sintered body into product pellets having a predetermined shape.

In the above configuration, a method of predicting the properties of coal ash will be described, and a method of manufacturing an artificial lightweight aggregate based on the coal ash property data obtained by the prediction method will be described.

First, as shown in FIG. 1, when coal is carried into a coal yard 52, it is individually stored in each pit 51 for each type of coal. Then, the coal information such as the amount of stored coal, the lot number, the date and time of acceptance, the properties of the coal, and the pit number specifying the pit 51 are registered in the monitoring device 60. Thereafter, the input amounts a to x of the coals from the respective pits 51 to the boiler 53 are determined, and the coal mixture of the different types of coal mixed at a ratio of the input amounts a to x is input to the boiler 53 and burned. You.

When the mixed coal is burned in the boiler 53, the coal ash is discharged together with the exhaust gas, passes through the air heater 54, and is captured by the dust collector 55. And the dust collector 55
The coal ash collected in the above is supplied to a cement-related facility 58 and an artificial lightweight aggregate manufacturing plant 59, and is used as a raw material of the artificial lightweight aggregate in the artificial lightweight aggregate manufacturing plant 59, for example.

When the coal ash is sent to the subsequent facilities 58 and 59 as described above, the properties of the coal ash are obtained by the monitoring device 60 based on the property prediction formula.
That is, the monitoring device 60 is the first term of the property prediction formula (A
The coal properties of the varieties × input amount a + the coal properties of the B type × input amount b +... + Coal properties of the X type × input amount x) 量 (input amount a + input amount b +... + Input amount x) After calculating the theoretical properties of the coal ash by substituting the input amounts a to x of the coal ash, by adding the correction value α of the second term of the property prediction formula to the theoretical properties, the actual components of the coal ash can be obtained. Determine the coal ash properties consisting of the melting temperature. Then, the coal ash property determined by the property prediction formula is transmitted as coal ash property data from the transmission unit to, for example, the artificial lightweight aggregate manufacturing plant 59.

The coal ash property data is received and taken into the control device of the artificial lightweight aggregate manufacturing plant 59. The coal ash sent from the dust collector 55 is stored in the pit 61 of the artificial lightweight aggregate manufacturing plant 59, as shown in FIG. At this time, the control device recognizes the properties of the coal ash based on the coal ash property data, and stores the coal ash in the same pit 61 if the same ash is supplied if the same ash is supplied. If the coal ash has been supplied, the operator is instructed to store the coal ash in another pit 61 or the supply path to the pit 61 is switched. Thereby, the coal ash stored in each pit 61 maintains the same property as the coal ash sent from the dust collector 55.

Next, when the artificial lightweight aggregate is manufactured in the artificial lightweight aggregate manufacturing plant 59, before the coal ash of the pit 61 is fed to the classifier 11, the coal ash is stored in the pit 61 serving as a feed source. The coal ash property data of the obtained coal ash is read out, and the granulation and firing conditions are determined based on the coal ash property data so that a desired artificial lightweight aggregate can be manufactured. At this time, the granulation and firing conditions can be obtained in a very short time only by the information processing of the coal ash property data in the control device.
Then, various control signals are output to the pan-type granulator 8, the linear-type moving sintering machine 12, and the like so that the manufacturing plant 59 operates under these conditions (condition setting step).

When the setting of the granulation and firing conditions for the artificial lightweight aggregate manufacturing plant 59 is completed, the coal ash in the pit 61 is fed to the classifier 11. Then, in the classifier 11, as the coal ash is rotated, each particle of the coal ash is given a centrifugal force due to the rotational flow and a drag force due to the air flow. Thereby, while the coarse particles of the coal ash are blown outward by the centrifugal force, the fine particles of the coal ash are sent in the inner circumferential direction together with the air, whereby the coal ash is sorted (classification step). Then, when coal ash, which is a coarse powder in which the weight ratio of the fine particles having a particle size of 10 μm or less occupies a predetermined value or less, is obtained by the classification, the first stage of the subsequent stage is sent from the outlet 11a.
It is sent to the hopper 1.

Next, coal ash is supplied to the kneader 5 from the first hopper 1. The filler is fed to the kneader 5 from the second to third hoppers 2 to 4 as needed. And
Water 5 'is injected by the kneader 5, and the coal ash and the filler are kneaded. The kneaded material is pulverized in the pulverizer 6 and supplied to the bread granulator 8 by the belt feeder 7 at a constant supply amount. Then, after being formed into raw pellets 65 having a predetermined particle size in the bread granulator 8, the raw pellets are fed to the linear moving firing machine 12 (raw pellet forming step).

The raw pellets 65 fed to the linear moving firing machine 12 are sintered through a drying-ignition-firing-cooling process. That is, the raw pellets 65 are supplied in a fixed amount onto the grate 21, and when the raw pellets 65 move along with the grate 21 and pass through the furnaces 22, 23, 24, the hot air is supplied from the hot air tube 28. The raw pellets are supplied and sucked downward by the blower 27 toward the lower side of the raw pellet (arrow B in the figure). Note that sintered pellets are laid for the floor of the raw pellets 65. Then, sintering is performed by the high-temperature air. Specifically, the raw pellets 65 are dried and dried by the preheating furnace 22.
Is dried, and then the dried pellets 6
Unburned coal in 5 'ignites. Further, the burning of the unburned coal in the dry pellets 65 'is shifted downward by the sintering / heating furnace 24, and the entire sintering is completed to form sintered pellets 65''(firing step).

Thereafter, the sintered pellet 65 ″ is conveyed to the cooling zone 29, and a part of the suction air of the blower 27 passes downward through the layer of the sintered pellet 65 ″ (arrow C in the figure). Thus, the sintered pellet 65 ″ is cooled. The pellet mass of the cooled sintered pellet 65 ″ is sent to the crusher 31 via the chute 30 and separated. Then, the separated sintered pellet 6
5 ″ is sieved into product pellets having a predetermined shape by the sieving machine 32 to obtain an artificial lightweight aggregate having a specific gravity of 1.25 or less.

Incidentally, the correction value α of the property prediction formula in the present embodiment was obtained based on the test results in Table 1. Specifically, as shown in FIG. 1, with respect to the coal mixture supplied to the boiler 53, 24 kinds of samples having different compositions are extracted,
Coal properties of each sample, ie, SiO ₂ , Al ₂ O ₃ ,
Coal obtained by calculating each component consisting of Fe ₂ O ₃ , CaO, Na ₂ O, K ₂ O, MgO and SO ₃ and the calculated value (theoretical value) of the melting temperature, and actually burning the mixed coal of each sample Analytical values of each property were obtained by analyzing the ash. Then, the average value of the calculated values and the analytical values of the 24 samples were obtained, and the difference obtained by subtracting the average value of the analytical values (analytical average value) from the average value of the calculated values (theoretical average value) was defined as the correction value α. Table 1 shows the results.

[0038]

[Table 1]

[0039]

According to the first aspect of the present invention, there is provided a coal ash property prediction method for predicting a coal ash property of coal ash generated by burning a coal mixture composed of a plurality of types of coal having different compositions. The coal properties of the i-th coal among the plurality of varieties used for coal blending are S (i), and the usage of the ith coal of the plurality of varieties is M (i). The difference between the theoretical average value of the coal ash properties obtained from the coal properties of each type and the analysis average value of the coal ash properties obtained by analyzing the coal ash generated by burning the various types of mixed coal is a correction value α. Coal ash property = と し た [S (i) · M (i)] / ΣM (i) +
The coal ash property is predicted based on a property prediction formula represented by a correction value α 2.

According to the above configuration, the actual coal ash properties of coal ash can be grasped in a shorter time than in the case of analysis based on the property prediction formula. As a result, the production can be started immediately after receiving the coal ash and the production conditions can be determined. Therefore, it is not necessary to provide a large number of large silos in a production facility for artificial lightweight aggregate, cement, or the like. As a result, the site area of the silo can be reduced, and the facility cost of the silo itself can be reduced.

According to a second aspect of the present invention, there is provided the method for predicting the properties of coal ash according to the first aspect, wherein the coal properties include Si.
O ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , CaO, Na ₂ O, K
_It consists of a composition (%) composed of ₂ O, MgO and SO ₃ and a melting temperature (° C.). The correction value α is 0.71 for SiO ₂ , 3.05 for Al ₂ O ₃ , and Fe ₂ O ₃ Is 0.3
1, CaO is -0.29, Na ₂ O is 0.23, K ₂ O
Is 0.29, MgO is 0.02, SO ₃ is 0.71, and the melting temperature (° C.) is −43. According to the above configuration, the coal ash properties obtained by the property prediction formula can be made very close to the actual coal ash properties.

According to a third aspect of the present invention, there is provided a method for manufacturing an artificial lightweight aggregate, wherein the artificial lightweight aggregate is within a standard based on the coal ash properties obtained by the method for predicting the properties of coal ash according to the first or second aspect. After the granulation and firing conditions are determined, the coal ash is classified into a coarse powder containing fine particles having a predetermined particle size, and the coarse powder is granulated and fired under the granulation and firing conditions to produce an artificial lightweight bone. It is characterized by using wood. According to the above configuration, an artificial lightweight aggregate can be manufactured immediately after receiving coal ash. Further, since the silo can be reduced in size, the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a process diagram of a coal combustion facility.

FIG. 2 is a process diagram of a facility for manufacturing an artificial lightweight aggregate.

[Explanation of symbols]

 1-4 1st-4th hopper 5 Kneader 6 Crusher 7 Belt feeder 8 Bread granulator 8a Granulator 8b Coating unit 11 Classifier 12 Linear type mobile baking machine 43 Pellet forming system 51 Pit 52 Coal yard 53 Boiler 54 Air heater 55 Dust collector 56 Desulfurization / denitration equipment 57 Chimney 58 Cement-related facility 59 Artificial lightweight aggregate manufacturing plant 60 Monitoring device 61 Pit 65 Raw pellet

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Jiro Terokina 4-3-1, Bingo-cho, Chuo-ku, Osaka-shi, Osaka Prefecture Kobe Steel, Ltd. Osaka branch office (72) Inventor Kazunobu Exit Bingo, Chuo-ku, Osaka-shi, Osaka 1-3 1-3, Kobe Steel, Osaka Branch Office (72) Inventor Masaji Abe 2109-8 Yashima Nishimachi, Takamatsu City, Kagawa Prefecture Techno Resources Co., Ltd. (72) Inventor Kyoya Tamura Takamatsu, Kagawa Prefecture 2109-8, Ichiyajima-Nishimachi Techno-Resource Co., Ltd. (72) Inventor Tokuji Akiba 2-2-5 Yanaka, Taito-ku, Tokyo (72) Inventor Masami Kato Morigo Shinoda, Miwa-cho, Kaifu-gun, Aichi Prefecture 78

Claims (3)

[Claims] 1. A coal ash property prediction method for predicting a coal ash property of coal ash produced by burning a coal mixture composed of a plurality of types of coal having different compositions, wherein the plurality of types used for the coal blend The coal properties of the i-th coal among S (i) and the usage of the i-th coal among the plurality of kinds are M (i), and are obtained from the coal properties of each kind used in the various types of coal blending. Coal ash properties when the difference between the theoretical average value of the coal ash properties obtained above and the analysis average value of the coal ash properties obtained by analyzing the coal ash generated by burning the above various types of coal is used as the correction value α. = Σ [S (i) · M (i)] / ΣM (i) +
A property prediction method for coal ash, wherein the property of coal ash is predicted based on a property prediction formula represented by a correction value α 2. 2. The coal properties include SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , CaO, Na
Composition (%) consisting of ₂ O, K ₂ O, MgO and SO ₃
And the melting temperature (° C.). The correction value α is 0.71 for SiO ₂ , 3.05 for Al ₂ O ₃ , and Fe ₂ O
₃ 0.31, CaO is -0.29, Na ₂ O 0.2
3, K ₂ O is 0.29, MgO is 0.02, SO ₃ 0.71, property prediction method of coal ash according to claim 1, melting temperature (℃) is characterized in that it is a -43 . 3. A method for predicting the properties of coal ash according to claim 1 or 2, wherein granulation and firing conditions for an artificial lightweight aggregate within the standard are determined based on the properties of the coal ash, and then the coal ash is classified. A coarse powder containing fine particles having a predetermined particle size, and granulating and firing the coarse powder under the above-mentioned granulation and firing conditions to obtain an artificial lightweight aggregate.