WO2022050407A1

WO2022050407A1 - Cement production method, production method for kneaded cement product, and biomass ash powdery material

Info

Publication number: WO2022050407A1
Application number: PCT/JP2021/032653
Authority: WO
Inventors: 裕介桐野; 美育 ▲高▼野; 建佑林; 俊一郎内田
Original assignee: 太平洋セメント株式会社
Priority date: 2020-09-07
Filing date: 2021-09-06
Publication date: 2022-03-10

Abstract

Provided is a technique that enable effective utilization of biomass ash while inhibiting a reduction in the strength of a produced cured cement product.　This method has: a step (a) for classifying biomass ash into rough powder and fine powder; and a step (b) for adding the rough powder obtained in step (a) at least to a cement clinker raw material to be put into a cement kiln, to a cement clinker obtained from the cement kiln, or to a cement obtained after a process of pulverizing the cement clinker.

Description

Cement manufacturing method, cement kneaded body manufacturing method, biomass ash powder granules

The present invention relates to a method for producing a cement and a method for producing a cement kneaded product, and more particularly to a method for producing a cement using biomass ash as a raw material for cement and a method for producing a cement kneaded product. The present invention also relates to biomass ash powder granules suitable for producing cement or a cement kneaded product.

Incinerator ash generated by incinerator of urban waste is desired to be recycled as a raw material for cement, etc. against the background of the tightness of disposal sites in recent years. In addition, the construction and operation of biomass power generation facilities are progressing due to various efforts toward the spread of renewable energy, and the amount of incineration ash (biomass ash) generated by biomass power generation is also increasing. Therefore, it is expected that biomass ash will be recycled as a raw material for cement as well as incineration ash such as municipal waste.

In relation to such a problem, for example, in Non-Patent Document 1 below, it is considered to apply biomass ash to a cement admixture.

In the above non-patent document 1, biomass ash is used as it is as a cement admixture. However, according to this method, there is a problem that the strength of a hardened cement product such as concrete or mortar using the obtained cement is significantly reduced.

An object of the present invention is to provide a technique capable of effectively utilizing biomass ash while suppressing a decrease in the strength of the produced cement hardened product.

The cement manufacturing method according to the present invention is
Step (a) of classifying biomass ash into coarse powder and fine powder,
The coarse powder obtained in the step (a) is applied to at least one of a cement clinker raw material to be charged into a cement kiln, a cement clinker obtained from the cement clinker, or a cement after crushing the cement clinker. It is characterized by having a step (b) of charging.

As described above, since the biomass ash has a high chlorine content, it is directly added to a cement clinker raw material, a cement clinker (hereinafter, both may be collectively referred to as “cement raw material”) or cement. In addition, the chlorine regulation value in cement may be exceeded, leading to reinforcement corrosion.

Of the biomass ash, the coarse powder with a relatively large particle size has a lower content of calcium, sulfur, chlorine, and carbon than the fine powder with a relatively small particle size, and is close to the composition of coal ash. Therefore, when used as a clinker raw material, homogeneity with that of a conventional clinker raw material can be ensured. In particular, since the content of sulfur and chlorine is low, it is difficult to generate coaching in the cement kiln, and it is difficult to increase the load on the chlorine bypass. Further, even when it is used as a mixed material of cement, it has an effect that the quality of cement can be homogenized because the content of calcium, sulfur, chlorine and carbon is low.

The step (a) is not particularly limited as long as it is an apparatus capable of classifying biomass ash at a classification point on the order of μm. Is preferably used, and particularly from the viewpoint of classification accuracy, it is preferable to use a cyclone type air separator, a vortex type centrifugal classification device, a sieving device, or the like.

As a specific method of the above step (b), it is put into the raw material mixing system equipment such as a mixer and a crusher for preparing the raw material of the cement cleaner, and to the preheater top and the calcination furnace before the cement kiln (rotary kiln). , Put into the cement kiln kiln butt, Put into the front of the cement kiln kiln, Put into the cleaner cooler to cool the cement clinker obtained by firing, Crushing device (mill) to crush the cement cleaner. It can be put into a mixing machine, put into a mixer for producing mixed cement, put into a concrete mixer, and the like. That is, the coarse powder of biomass ash obtained in the step (a) can be added to various stages during cement production, and can be suitably used as a raw material for cement clinker or a cement mixture.

In the following, when the term "mixed material" is used in the present specification, it means a material to be added to cement clinker or cement regardless of the cement manufacturing stage.

Utilizing the fact that the characteristics such as the chemical composition of the classified biomass ash (that is, coarse powder and fine powder) obtained through the step (a) are different, the influence on the clinker characteristics and the clinker manufacturing process and the influence on the cement characteristics. All or part of the coarse powder or fine powder can be added to the raw material or mixed material of cement clinker. As a result, the composition or characteristics of the cement clinker or cement will be different from the case where the biomass ash (raw ash) is added as it is.

It should be noted that at least a part of the coarse powder obtained in the step (a) may be added to the cement raw material or cement, and it is not always necessary that all the coarse powder is added to the cement raw material or cement. The residual coarse powder can also be used, for example, as a fine aggregate.

This step (a) is preferably carried out on biomass ash (preferably dry ash) in a state where water has not been added and the hydrate formation reaction has not progressed. More specifically, the biomass ash is preferably fly ash generated from a fluidized bed type combustion furnace and is preferably dry ash.

For example, when the biomass ash is wet ash and aggregates or hydrates are formed, there is a possibility that a large amount of chlorine is contained on the coarse powder side even when the classification is performed. ..

As used herein, the term "dry ash" refers to biomass ash that has been recovered in a dry state, has not been watered by the time it is classified, and has not aggregated or formed hydrates. Point to. Further, the dry ash is in a state where a large amount of water is added and dispersed even if water is added before the classification treatment, and a case where hydrate is not formed by long-term storage is also included. Further, in the present specification, "wet ash" is, for example, water-cooled or sprinkled with water-cooled or sprinkled with main ash which is an incineration residue discharged from the bottom of an incinerator or fly ash collected by a dust collector or the like. Refers to those collected in a state containing ash and those that have been dried. Generally, the wet ash has a water content of 15% by mass or more.

The step (a) is preferably a step of classifying with 20 μm to 100 μm as a classification point. This is particularly efficient because chlorine and sulfur are predominantly distributed to the fine powder side.

The step (b) may be a step of putting the coarse powder obtained in the step (a) into a cement clinker obtained from the cement kiln or the cement clinker after the crushing treatment.

The cement manufacturing method includes a step (c) of pulverizing at least a part of the coarse powder obtained in the step (a).
The step (b) is a step of putting the coarse powder after being crushed by the step (c) into a cement clinker obtained from the cement kiln or the cement clinker after the crushing treatment. It doesn't matter.

According to this method, the coarse powder is crushed and put into a cement clinker or cement in a state where the particle size is made fine, so that the strength of the cement can be increased. The crushing of the coarse powder may be performed at the same time as the crushing of the cement clinker.

The cement manufacturing method may include a step (d) of putting the fine powder obtained in the step (a) into the cement clinker raw material.

Biomass ash has low activity, but finer powder with smaller particle size has higher activity and higher alkali metal content. Therefore, as in the above method, the fine powder obtained after classifying the biomass ash is mixed with the cement clinker raw material to activate the pozzolan reaction. Therefore, the strength of the hardened cement product is higher than that in the case where the biomass ash before classification (hereinafter, may be referred to as “raw ash”) is added to the cement clinker raw material.

The step (b) may be a step of putting the coarse powder obtained in the step (a) into a cement clinker raw material to be put into a cement kiln.

The cement manufacturing method includes a step (d) of putting the fine powder obtained in the step (a) into a cement clinker obtained from the cement kiln or the cement clinker after the crushing treatment. It doesn't matter.

Biomass ash has low activity, but finer powder with smaller particle size has higher activity and higher alkali metal content. Therefore, as in the above method, the fine powder obtained after classifying the biomass ash is mixed with the cement clinker or cement to activate the pozzolan reaction. Therefore, the strength of the hardened cement product is higher than that in the case where the biomass ash before classification (hereinafter referred to as “raw ash”) is put into cement clinker or cement.

The cement manufacturing method includes a step (e) of washing the fine powder obtained in the step (a) with water.
The step (d) may be a step of adding the fine powder after being washed with water by the step (e).

According to the studies by the present inventors, biomass ash contains harmful components in cement and concrete, and the quality is not stable due to the presence of easily reactive calcium components. Therefore, cement raw materials and the like are used. There was a concern that it would be restricted by the recycling of resources. On the other hand, according to the above method, the biomass ash that has undergone the washing step (e) is charged into the cement raw material (cement clinker raw material, cement clinker) or cement, so that the charged biomass ash is chlorine, which is a cement repellent component. Is efficiently removed, and the corrosion of the reinforcing bars of concrete as a hardened cement product can be suppressed. In addition, heavy metals such as selenium and chromium, which may pollute the environment, and easily reactive calcium oxide and calcium hydroxide are removed, and the quality of cement can be homogenized. When the biomass ash that has undergone the water washing step (e) is used as a cleanser raw material, clogging due to adhesion of a low melting point substance to the preheater, the kiln butt, and the kiln is suppressed.

In particular, according to the study by the present inventors, it was confirmed that most of the chlorine content contained in the biomass ash is contained in the fine powder when the coarse powder obtained after classifying the biomass ash and the fine powder are compared. Therefore, according to the above method, chlorine contained in the biomass ash can be efficiently removed while suppressing the amount of water used for washing with water.

The water washing step (e) includes a step (e1) of adding water to biomass ash to form a slurry, a step of supplying water washing water to the slurry and washing it with water (e2), and dehydration of the slurry after washing with water. It is preferable to have the step (e3). Chlorine and heavy metals can be removed because the dehydrated product is obtained by washing the slurry with water and then dehydrating it.

The cement manufacturing method may include a step (f) of oxidizing the biomass ash during or after the execution of the step (e).

According to the above method, since the pH at the time of washing with water is adjusted to the acidic side, chlorine can be removed more efficiently. In addition, even if the biomass ash contains a large amount of easily reactive calcium oxide or calcium hydroxide, it can be replaced without omission in the form of calcium carbonate or calcium sulfate, so that the quality such as the fluidity of cement is uniform. Can be transformed into.

In the step (f), an acid solution may be added during washing of the biomass ash, or a carbon dioxide (CO ₂ ) -containing gas may be blown into the biomass ash, or the CO ₂ -containing gas may be added to the biomass ash after the washing treatment. It does not matter if it is blown into it. In particular, by using the combustion exhaust gas of cement kiln, the bleed gas of chlorine bypass, and the combustion exhaust gas of biomass incineration equipment and biomass power plant as CO ₂ containing gas, CO ₂ contained in these gases can be changed to calcium carbonate. Since it can be fixed to biomass ash, it can be expected to reduce CO ₂ emissions. In addition, harmful gases such as sulfur acid substances (SO _x ) contained in the exhaust gas can be converted into calcium sulfate and immobilized on biomass ash.

Further, especially in the step (f), by carbonating the biomass ash during the washing with water according to the step (e), the calcium content contained in a large amount in the waste liquid after washing with water can be precipitated as calcium carbonate, so that scale is generated. It is suppressed. As a result, it is possible to prevent the piping for wastewater treatment from being blocked.

The cement manufacturing method may include a step of removing unburned carbon contained in the biomass ash during the execution of the step (e).

Biomass ash may contain a lot of unburned carbon. For this reason, when biomass ash containing a large amount of carbon is used as a raw material for cement clinker, the temperature of the preheater may rise, and when used as a mixed material, darkening of concrete and a water reducing agent may be adsorbed on carbon. May cause a decrease in liquidity.

On the other hand, according to the above method, unburned carbon can be removed during washing with water, so that the above-mentioned problems can be suppressed. Specifically, the amount of unburned carbon contained may be reduced by performing flotation by mixing a decombustible carbon agent such as oil or a surfactant.

Further, in the method for producing a cement kneaded body according to the present invention, the step (a) of classifying biomass ash into coarse powder and fine powder and the coarse powder obtained in the step (a) are cemented without crushing. It is characterized by having a step (g) of mixing with water.

In the present specification, the "cement kneaded body" is a concept including concrete and mortar, and includes the state before hardening and the state after hardening. Further, the "hardened cement product" refers to a state after the cement kneaded product is hardened.

In recent years, from the viewpoint of environmental protection, a material that replaces mountain sand and river sand has been desired as an aggregate used in the production of concrete. On the other hand, biomass such as palm palm pattern is attracting attention as a carbon-neutral fuel, and the amount used is increasing. Along with this tendency, a large amount of biomass ash is generated. Therefore, in order to prevent the tightness of the biomass ash disposal site, the utilization of biomass ash is required. Therefore, the present inventors have also studied the use of biomass ash as a substitute material for aggregates.

In Non-Patent Document 1 above, incinerated ash obtained by burning woody biomass alone is classified by a sieve with 90 μm as a classification point, and then the residual portion (coarse powder) of the sieve is replaced by 10% with respect to the amount of fine bone material. The compressive strength of the obtained mortar specimen has been verified.

However, biomass ash contains a lot of chlorine. When concrete is manufactured using the fine aggregate substitute obtained by the method described in Non-Patent Document 1, the chlorine content of the concrete may exceed the regulation value, and in some cases, rebar corrosion may occur. be.

On the other hand, according to the above method, since the coarse powder classified in the step (a) has a relatively large particle size among the biomass ash, the chlorine content is lower than that of the fine powder. There is. This makes it possible to keep the amount of chlorine contained in the obtained cement kneaded product within the regulated value even when the cement kneaded product is produced by using it as an alternative material to the fine aggregate.

This step (a) is preferably carried out on biomass ash (preferably dry ash) in a state where water has not been added and the hydrate formation reaction has not progressed. For example, when the biomass ash is wet ash and aggregates or hydrates are formed, there is a possibility that a large amount of chlorine is contained on the coarse powder side even when the classification is performed. ..

The step (a) is not particularly limited as long as it is an apparatus capable of classifying biomass ash at a classification point on the order of μm. Is preferably used, and particularly from the viewpoint of classification accuracy, it is preferable to use a cyclone type air separator, a vortex type centrifugal classification device, a sieving device, or the like. At this time, it is preferable to classify using a reference value in the range of 30 μm to 100 μm as a classification point.

In the step (g), the adjusting powder is mixed with the coarse powder, so that the proportion of amorphous material in the mixture of the coarse powder and the adjusting powder is adjusted to be 60% by mass or less. It may be a step of mixing with cement and water in a state of being.

For example, when the amorphous ratio of the crude powder obtained after classification exceeds 60% by mass, a mixture is mixed by mixing an adjusting powder (other biomass ash, etc.) having a low amorphous ratio. The total amorphous ratio can be 60% by mass or less. By utilizing this mixture as a partial substitute material for the fine aggregate, expansion due to the alkali-silica reaction is less likely to occur.

The coarse powder classified in the step (a) may be mixed in the step (g) after being washed with water. This makes it possible to further reduce the chlorine, alkali metal, and sulfur components contained in the crude powder. In addition, it is possible to reduce the amounts of heavy metals such as selenium and chromium, which may pollute the environment, and easily reactive calcium oxide and calcium hydroxide.

In the method for producing the cement kneaded body, the fine powder obtained in the step (a) is crushed into a cement clinker raw material to be charged into a cement kiln, a cement clinker obtained from the cement kiln, or the cement clinker. It may have a step (d) of putting it into at least one of the cements obtained later.

Biomass ash has low activity, but finer powder with smaller particle size has higher activity and higher alkali metal content. Therefore, as in the above method, the fine powder obtained after classifying the biomass ash is the cement clinker raw material, the cement clinker (hereinafter, both may be collectively referred to as "cement raw material"), or cement. The reaction is activated by mixing with the cement. Therefore, the strength of the hardened cement product is higher than that in the case where the biomass ash before classification is put into the cement raw material or cement.

That is, according to the above method, the coarse powder having a relatively low chlorine content is used as a partial substitute material for the fine aggregate, and the fine powder having a relatively high chlorine content is one of the cement raw materials and the cement mixture. Used as a substitute material for parts. This makes it possible to effectively utilize the biomass ash without leaving it.

When fine powder after classification of biomass ash is added during cement production, cement with a high alkali metal content can be produced. When this cement and aggregate are mixed to form a hardened cement (concrete), an alkali-silica reaction may occur. On the other hand, by adding latent water-hardening substances such as blast furnace slag and pozzolan (including natural pozzolan such as silica stone powder and stone powder, and artificial pozzolan such as fly ash and calcined clay) together with fine powder, it is alkaline. The silica reaction can be suppressed.

When the amorphous ratio of the biomass ash powder granules (coarse powder) exceeds 60% by mass, or when the substitution rate of the fine aggregate of the biomass ash powder granules exceeds 40% by mass, alkaline silica is similarly applied. From the viewpoint of suppressing the reaction, at least one of the latent water-hardening substance and the pozzolan may be mixed as an admixture in the step (g).

The biomass ash powder granules according to the present invention are characterized in that the value (D10) of the cumulative volume percentage of the particle size distribution of 10% is 35 μm or more.

According to the above configuration, a biomass ash powder granule having a suppressed chlorine (Cl) content is realized. When a cement kneaded product is produced by using the biomass ash powder granules as a partial substitute material for the fine aggregate, it is possible to suppress an increase in the amount of chlorine contained in the obtained cement kneaded product. That is, the biomass ash powder granules may be used for replacement with fine aggregates for hardened cement products.

In this case, it is preferable that 5% by mass to 40% by mass of the fine aggregate contained in the hardened cement (cement kneaded body) is composed of the biomass ash powder granules. According to the above configuration, a cement kneaded product in which an increase in chlorine content is suppressed while replacing a part of the fine aggregate with biomass ash powder granules is realized.

However, the biomass ash powder granules are finer than the particle size of general fine aggregate specified in JIS A5005 "Crushed stone and crushed sand for concrete". Therefore, when the biomass ash powder granules are mixed in a proportion exceeding 40% by mass of the total fine aggregate, the proportion of the fine powder contained in the fine aggregate becomes too high, which affects the fluidity of the cement kneaded body. It can occur. On the other hand, when the biomass ash powder granules are mixed at a ratio of less than 5% by mass of the whole fine aggregate, the biomass ash whose amount is increasing cannot be fully utilized.

Of the biomass ash, the coarse powder with a relatively large particle size has a lower content of calcium, sulfur, chlorine, and carbon than the fine powder with a relatively small particle size. Therefore, by setting D10 to 35 μm or more, biomass ash powder granules having a low chlorine content (chlorine concentration) can be obtained. More preferably, the D10 of the biomass ash powder is 50 μm to 115 μm. By setting the D10 of the biomass ash powder granules to 115 μm or less, the action as a binder (pozzolan reaction) can be expected, so that the strength of the hardened cement product can be ensured. From the same viewpoint, the value (D90) in which the cumulative volume percentage of the particle size distribution of the biomass ash powder is 90% is preferably 80 μm to 400 μm.

The value (D50) of the cumulative volume percentage of the particle size distribution of the biomass ash powder is preferably 100 μm to 300 μm, more preferably 150 μm to 250 μm, and 175 μm to 200 μm. Is particularly preferable.

The particle size distribution of the biomass ash powder can be measured by, for example, a laser diffraction / scattering type particle size distribution measuring device.

The chlorine (Cl) content of the biomass ash powder granules is preferably 0.1% by mass or less, and more preferably 0.05% by mass or less.

The proportion of chlorine contained in the biomass ash powder granules can be measured by a well-known method, and for example, wet quantitative analysis, calibration curve method using a fluorescent X-ray apparatus, and the like are preferably exemplified.

The biomass ash powder is preferably a powder having an amorphous content of 60% by mass or less.

As described above, the biomass ash powder granules have a D10 of 35 μm or more, and have a larger particle size than the cement used in the production of the cement kneaded product. When the proportion of amorphous material contained in the biomass ash powder granules having such a particle size increases, when a cement kneaded body is produced using the biomass ash powder granules, it becomes possible to combine with alkali metals (Na, K). The reactivity increases and the amount of alkaline silica gel generated increases, and a phenomenon (alkali silica reaction) in which durability is lowered due to water absorption expansion accompanying this reaction is likely to occur. By setting the proportion of amorphous material contained in the biomass ash powder to 60% by mass or less, the reactivity with the alkali metal is lowered and the alkali silica reaction is less likely to occur. The alkali-silica reaction is also referred to as "alkali-aggregate reaction".

From the above viewpoint, the proportion of amorphous material contained in the biomass ash powder granules is more preferably 50% by mass or less, further preferably 40% by mass or less, and particularly preferably 30% by mass or less. preferable.

In measuring the proportion of amorphous material contained in the biomass ash powder, for example, a method of calculating the measurement result of X-ray diffraction by Rietveld analysis (XRD-Rietveld method) can be used.

The content of SO ₃ contained in the biomass ash powder is preferably 1% by mass or less, more preferably 0.5% by mass or less, and particularly preferably 0.2% by mass or less. If the content of SO ₃ contained in the biomass ash powder exceeds 1% by mass, it affects the quality of the hardened cement product, such as showing abnormal expansion when used in the production of a cement kneaded product. there is a possibility.

The method for measuring the content of SO ₃ contained in the biomass ash powder can be measured by a well-known method, and for example, wet quantitative analysis, calibration curve using a fluorescent X-ray apparatus, and the like are preferably exemplified. ..

The ignition loss of the biomass ash powder is preferably 3% by mass or less, and particularly preferably 2% by mass or less. When the ignition loss of the biomass ash powder granules exceeds 3% by mass, the amount of unburned carbon increases, and when used for the production of a cement kneaded body, the chemical admixture added to the kneaded body is adsorbed. It may adversely affect the fluidity and air volume, and may cause darkening of the obtained hardened cement product.

The method for measuring the ignition loss of the biomass ash powder granules can be measured by a well-known method, and for example, a method based on JIS R5202 "Cement Chemical Analysis Method" is preferably exemplified.

The biomass ash powder granules may be used for partial replacement with a cement clinker raw material to be put into a cement kiln.

The biomass ash powder granules may be used for partial replacement of cement clinker or a cement mixture to be charged into cement after crushing the cement clinker.

In particular, when the proportion of amorphous material contained in the coarse powder obtained after the classification of biomass ash is high to the extent of exceeding 60% by mass, if this coarse powder is used as a partial substitute material for fine aggregate, an alkaline silica reaction will occur. May occur. On the other hand, the crude powder obtained after classifying the biomass ash has a low content of calcium, sulfur, chlorine, and carbon and is close to the composition of coal ash. Uniformity can be ensured. Since this coarse powder has a particularly low content of sulfur and chlorine, it has the effect that coaching in the cement kiln is less likely to occur and the load on the chlorine bypass is less likely to increase. Further, even when it is used as a mixing material, it can be used as a cement mixing material or a concrete admixture having a low content of sulfur, chlorine, and carbon, which affect the quality of concrete, and whose reactivity is enhanced by pulverization. ..

According to the present invention, it is possible to effectively utilize biomass ash during cement production while suppressing a decrease in the strength of the produced hardened cement product.

It is a figure which shows typically the processing flow of the cement manufacturing method in 1st Embodiment. It is a block diagram which shows typically the structure of the processing system for carrying out the cement manufacturing method in 1st Embodiment. It is a graph which shows the particle size distribution of the incinerator fly ash obtained from the biomass power generation facility P1 used in the verification 1. It is a block diagram schematically showing another configuration of the processing system. It is a figure which shows typically the processing flow of the cement manufacturing method in 2nd Embodiment. It is a figure which shows typically an example of the detailed processing flow of a water washing process. It is a block diagram which shows typically the structure of the processing system for carrying out the cement manufacturing method in 2nd Embodiment. It is a block diagram schematically showing an example of the structure of the washing equipment provided in the processing system shown in FIG. 7. It is a figure which shows an example of the processing flow when the oxidation process and the unburned carbon removal process are executed together with a water washing process. It is a block diagram schematically showing another example of the structure of the water washing facility in FIG. 7. It is a block diagram schematically showing another configuration of the treatment system for carrying out the cement manufacturing method in the second embodiment. It is a block diagram schematically showing another configuration of the treatment system for carrying out the cement manufacturing method in the second embodiment. It is a figure which shows typically another processing flow of the cement manufacturing method in 2nd Embodiment. It is a block diagram schematically showing another configuration of the treatment system for carrying out the cement manufacturing method in the second embodiment. It is a figure which shows typically the process flow of the manufacturing method of a cement and a cement kneaded body in 3rd Embodiment. It is a block diagram which shows typically the structure of the processing system for carrying out the manufacturing method of cement and a cement kneaded body in 3rd Embodiment. It is a drawing which shows another processing flow schematically of the manufacturing method of a cement and a cement kneaded body in 3rd Embodiment. It is a block diagram schematically showing another configuration of the treatment system for carrying out the method of manufacturing a cement and a cement kneaded body in a third embodiment. It is a drawing which shows another processing flow schematically of the manufacturing method of a cement and a cement kneaded body in 3rd Embodiment. It is a block diagram schematically showing another configuration of the treatment system for carrying out the method of manufacturing a cement and a cement kneaded body in a third embodiment. It is a block diagram schematically showing another configuration of the treatment system for carrying out the method of manufacturing a cement and a cement kneaded body in a third embodiment. It is a drawing which shows another processing flow schematically of the manufacturing method of a cement and a cement kneaded body in 3rd Embodiment. It is a block diagram schematically showing another configuration of the treatment system for carrying out the method of manufacturing a cement and a cement kneaded body in a third embodiment. It is a polarizing microscope observation image of biomass ash.

[Biomass ash]
The present invention relates to a technique for using biomass ash in the production of cement or a cement kneaded product (hardened cement product). First, the biomass ash to which the present invention is applied will be described.

The biomass ash to which the present invention is applied generally includes incinerator ash of biomass, and includes, for example, incinerator ash of plants and bamboo and incinerator ash of food residue. The biomass ash contains water-soluble alkali metal chloride, alkali metal sulfate, and alkali metal carbonate. Compared to municipal waste incineration ash and chlorine bypass dust, biomass ash has the advantage that the proportion of alkali metal sulfate and alkali metal carbonate is large and the concentration of alkaline chlorine is low.

Since the biomass ash is an incinerator ash, it contains a glass component having pozzolan reactivity like coal ash. Among the biomass ash, the incinerated ash of vegetation and bamboo has a relatively high content of K ₂ O, and more than half of potassium (K ₂ O) is contained in the glass phase. Therefore, since biomass ash has high activity when used as a mixed material, it is preferable to use it at the time of cement production.

The content of K ₂ O in the biomass ash is preferably 2% by mass to 10% by mass, more preferably 3% by mass to 8% by mass, and further preferably 3% by mass to 5% by mass. More preferred. If the K ₂ O content of the biomass ash is less than 2% by mass, the strength of the cement when used as a mixed material may be low, and the required amount as a material to be added to the cement is secured in the first place. It may not be possible. On the other hand, when the K ₂ O content of biomass ash exceeds 10% by mass, the amount used as a raw material for cement clinker is limited, and the occurrence of alkaline aggregate reaction when used as a mixed material increases. There is a risk.

The total alkali concentration contained in the biomass ash is preferably 2% by mass to 11% by mass, more preferably 3% by mass to 6% by mass in terms of R ₂ O (R ₂ O = Na ₂ O + 0.658 × K ₂ O). .. The sulfur oxide (SO ₃ ) concentration contained in the biomass ash is preferably 0.5% by mass to 6% by mass, more preferably 1% by mass to 5% by mass.

In a biomass power plant, co-firing of biomass and coal may be carried out, and the biomass ash to which the present invention is applied includes ash generated when such co-firing is carried out. However, since coal ash obtained by burning coal generally has a low K ₂ O content, the activity of biomass ash differs depending on the amount of coal used during co-firing. Therefore, from the viewpoint of recycling as a mixed material at the time of cement production, in the case of co-firing with coal, it is preferable that the ash is obtained from a fuel having a biomass ratio of 50% by mass or more.

As the biomass ash to which the present invention is applied, palm coconut ash (PKS ash) obtained by using palm coconut husk as fuel is also preferably exemplified among the incinerated ash of vegetation and bamboo. Palm palm husks are a by-product of palm oil production and are primarily used in the natural biomass energy industry. Palm coconut shell is a yellowish brown fibrous substance with low ash content, its particle size is about 5 mm to 40 mm, and its calorific value is about 4000 Kcal / kg. Therefore, in energy production using renewable resources, palm coconut husks. In recent years, shells have been increasingly used as fuel for biomass power generation.

Generally, there are stoker type and fluidized bed type combustion furnaces for biomass power generation, but in fluidized bed type and pressurized fluidized bed type combustion furnaces, limestone is added to perform desulfurization in the furnace. Will be done. Therefore, the biomass ash from such a combustion furnace contains a large amount of calcium component and sulfur component, and for example, the CaO content is generally 5% by mass to 45% by mass. The morphology of the Ca compound derived from the added limestone includes forms such as CaO (quick lime), Ca (OH) ₂ (slaked lime), CaCO ₃ (limestone), and CaSO ₄ (plaster).

The CaO content of the biomass ash to which the present invention is applied is preferably 10% by mass to 40% by mass, preferably 15% by mass to 30% by mass, from the viewpoint of the strength of cement when recycled as a mixed material. It is more preferable to have.

The ash type of the biomass ash to which the present invention is applied may be the main ash that remains unburned at the bottom of the combustion furnace of biomass power generation, or soot dust that is contained in the combustion exhaust gas and floats as a gas is collected by a dust collector. It does not matter if it is the fly ash obtained by the above. Of these, fly ash is preferable because it has a higher concentration of alkali metal and chlorine, and chlorine is easily separated by washing with water, which is efficient.

Further, the biomass ash is preferably dry ash. Biomass ash that has been sprayed with water once may become granular, or chlorine may be incorporated into the produced hydrate, making it difficult to separate chlorine by classification or washing with water. As the dry ash, for example, it is preferable that Friedel's salt or ettringite, which is a hydrate, is not detected by powder X-ray diffraction. Further, the dry ash preferably has a water content of 10% by mass or less, and more preferably 5% by mass or less. Alternatively, the ignition loss is preferably 10% or less. The water content can be determined as the mass reduction rate when dried at 105 ° C. The ignition loss can be determined as the mass loss rate when the object dried at 105 ° C. is heated at 975 ° C.

Alternatively, the amount of structural water of the hydrate in the biomass ash may be obtained as the amount of hydrate produced by subtracting the amount of decarbonization by calcium carbonate from the loss on ignition. The amount of hydrate produced is preferably 5% or less, more preferably 3% or less.

The particle size of the biomass ash is, for example, preferably 200 μm or less, more preferably 150 μm or less, and further preferably ₉₀ μm or less, which increases the strength of the cement. The particle size can be measured by using a laser diffraction / scattering type particle size distribution measuring device, for example, by using ethanol as a dispersion medium with MW3300EXII manufactured by Microtrac Bell, and measuring after ultrasonic dispersion for 1 minute. can. The D ₅₀ value means the particle size at a cumulative 50% in the volume-based particle size distribution.

[First Embodiment]
The cement manufacturing method, the cement kneaded body manufacturing method, and the first embodiment of the biomass ash powder granules according to the present invention will be described. FIG. 1 is a drawing schematically showing a processing flow of the cement manufacturing method in the present embodiment. FIG. 2 is a block diagram schematically showing a configuration of a treatment system for implementing the cement manufacturing method in the present embodiment.

The processing system 1 shown in FIG. 2 includes a raw material tank 3 in which the cement clinker raw material Y1 is stored, a powder storage tank 5 in which the biomass ash B1 is stored, a clinker production facility 10, a classification facility 20, and a first crushing facility. 30 and. The clinker manufacturing facility 10 is a facility for firing the cement clinker raw material Y1 to generate the cement clinker Cn1, and is a preheater that preheats the cement clinker 12 for firing and the cement clinker raw material Y1 before being charged into the cement kiln 12. 11 and a clinker cooler 13 for cooling the cement clinker Cn1 after firing. The treatment system 1 in the present embodiment can also be referred to as a "cement manufacturing system".

As shown in FIG. 1, the cement manufacturing method of the present embodiment includes a step S10 for classifying the biomass ash B1 and a step S20 for adding or adding the classified biomass ash B1 to a cement raw material or the like. In the following, the charging or adding process is collectively referred to as a “loading” process.

(Classification step S10)
The biomass ash B1 stored in the powder storage tank 5 is classified into coarse powder B1C having a coarse particle size and fine powder B1F having a fine particle size based on a predetermined classification point by the classification equipment 20. The classification point defined in the classification step S10 is preferably 20 μm to 100 μm, more preferably 30 μm to 90 μm, and particularly preferably 38 μm to 75 μm or less.

The classification equipment 20 is not particularly limited as long as it can classify the biomass ash B1 at the classification points on the order of μm as described above, and for example, a sieve, an inertial classification device, a centrifugal classification device, a gravity type classification device, or the like is suitable. From the viewpoint of classification accuracy, it is preferable to use a cyclone type air separator, a sieving device, or the like. However, when the water washing step S30 described later is performed, it is efficient to perform the classification in a wet manner.

In the fluidized bed type incinerator, sand mainly composed of quartz as a fluidized medium and limestone for desulfurization are put into the incinerator. The fly ash of biomass ash from such an incinerator includes relatively coarse-grained melt-solidified and aggregated glass and sand-derived substances, relatively fine-grained volatile alkali metal salts, and the above-mentioned limestone-derived substances, and fine particles. Includes glass particles. Therefore, when the particle size distribution of biomass ash is expressed by frequency, if the classification point is set between the peaks on the fine grain side and the peaks on the coarse grain side, chlorine, sulfur, and calcium can be efficiently separated. ..

FIG. 3 is a graph showing the particle size distribution of incinerated fly ash obtained from the biomass power generation facility P1 used in the verification 1 described later. According to the graph of FIG. 3, it is confirmed that peaks having high frequency values appear on the fine powder side having a relatively fine particle size and the coarse powder side having a relatively coarse particle size. It is considered that the fine powder side is derived from limes and alkali metal salts, and the coarse powder side is derived from quartz and feldspar. Therefore, it can be seen that chlorine, sulfur, and calcium can be efficiently separated by classifying the particle size of the region between these mountains (the region of the valley) as the classification point. When the incinerator that is a fluidized bed type is equipped with equipment for recovering incinerator ash that has settled in boilers, air preheaters, high-temperature gas channels, etc., and equipment for recovering incinerator ash such as cyclones and bag filters. There is. Since the particle size of the incinerator ash collected by these collection facilities is different, it is possible to replace them with a classification device by separating and collecting them.

The classification equipment 20 may be equipped with a storage tank for biomass ash B1. Further, a supply device for quantitatively supplying the biomass ash B1 from this storage tank to the classification facility 20 may be attached. These storage tanks and supply devices may be appropriately used depending on the state of the received biomass ash B1.

As a guideline for classification in the classification step S10, first, the particle size of the coarse powder B1C obtained after classification can be mentioned. Specifically, the coarse powder B1C obtained after the classification is classified in the classification step S10 so that the D10 value of the particle size is 35 μm or more. More preferably, the D10 value of the crude powder B1C after classification is 50 μm to 115 μm.

The median value (D50) of the particle size of the coarse powder B1C is preferably 100 μm to 300 μm, more preferably 150 μm to 250 μm, and particularly preferably 175 μm to 200 μm. The D90 value of the particle size of the coarse powder B1C is preferably 80 μm to 400 μm.

According to the coarse powder B1C showing the above particle size distribution, the chlorine (Cl) content is typically reduced to 0.2% by mass or less. The chlorine content of the crude powder B1C is preferably 0.01% by mass to 0.1% by mass, and more preferably 0.01% by mass to 0.05% by mass.

The chlorine concentration ratio (ratio of chlorine content) of the fine powder B1F to the coarse powder B1C is preferably 4 or more, more preferably 8 or more, and further preferably 12 or more. The chlorine content of the fine powder B1F is, for example, typically 0.2% by mass to 2% by mass, and more typically 0.3% by mass to 1.5% by mass. That is, by this classification step S10, the biomass ash B1 (raw ash) is separated into a coarse powder B1C having a relatively low chlorine content and a fine powder B1F having a relatively high chlorine content.

The activity index of the fine powder B1F obtained in the classification step S10 is higher than that of biomass ash (raw ash) B1, typically 70% or more in 7 days, 65% or more in 28 days, and more typically. Will be 75% or more in 7 days and 70% or more in 28 days. The activity index contained in the biomass ash B1 (B1C, B1F) can be measured by a well-known method, and for example, a method based on JIS A 6201: 2015 “Fly ash for concrete” is preferably exemplified.

The yield of the fine powder B1F is preferably 10% by mass to 80% by mass, more preferably 20% by mass to 70% by mass, and further preferably 30% by mass to 60% by mass. The yield of the fine powder B1F may be the ratio of the total mass of the obtained fine powder B1F to the total mass of the biomass ash B1 before the execution of the classification step S10. On the other hand, the yield of the crude powder B1C is preferably 20% by mass to 90% by mass, more preferably 30% by mass to 80% by mass, and further preferably 40% by mass to 70% by mass. ..

The total alkali concentration ratio of the fine powder B1F to the coarse powder B1C is preferably 1.05 or more, preferably 1.1 or more in terms of R ₂ O (R ₂ O = Na ₂ O + 0.658 × K ₂ O). More preferably, it is more preferably 1.2 or more. The total alkali concentration of the fine powder B1F is, for example, typically 2% by mass to 10% by mass, and more typically 3% by mass to 8% by mass. On the other hand, the total alkali concentration of the crude powder B1C is typically reduced to 0.5% by mass to 6% by mass, and more typically to 2% by mass to 5% by mass. The total alkali concentration contained in the biomass ash B1 (B1C, B1F) can be measured by a well-known method, and for example, wet quantitative analysis, calibration curve using a fluorescent X-ray apparatus, and the like are preferably exemplified. A similar method can be used for measuring the concentrations of chlorine, sulfur oxides, calcium oxide and the like.

The ratio of the sulfur oxide (SO ₃ ) content of the fine powder B1F to the coarse powder B1C is preferably 5 or more, more preferably 10 or more, and further preferably 20 or more. The sulfur oxide content of the fine powder B1F is, for example, typically 1% by mass to 6% by mass, and more typically 2% by mass to 5% by mass. On the other hand, the sulfur oxide content of the crude powder B1C is typically reduced to 1% by mass or less, more preferably 0.5% by mass or less, and particularly preferably 0.2% by mass or less. ..

The calcium oxide concentration ratio of the fine powder B1F to the coarse powder B1C is preferably 1.5 or more, more preferably 2 or more, and further preferably 3 or more. The calcium oxide concentration of the fine powder B1F is, for example, typically 8% by mass to 40% by mass, and more typically 15% by mass to 35% by mass. On the other hand, the calcium oxide concentration of the crude powder B1C is typically reduced to 3% by mass to 15% by mass, and more typically reduced to 5% by mass to 10% by mass.

The ignition loss of the crude powder B1C is preferably 3% by mass or less, and particularly preferably 2% by mass or less. On the other hand, the ignition loss of the fine powder B1F is typically 5% by mass to 15% by mass, and more typically 5% by mass to 10% by mass. That is, by this classification step S10, the coarse powder B1C having a relatively low ignition loss and the fine powder B1F having a relatively high ignition loss are separated. The method for measuring the ignition loss of biomass ash B1 (B1C, B1F) can be measured by a well-known method, and for example, a method based on JIS R5202 "Chemical analysis method for cement" is preferably exemplified.

This classification step S10 corresponds to the step (a).

(Injection step S20)
The crude powder B1C obtained in the classification step S10 is added (added) as a raw material for cement clinker or as a mixed material to cement clinker or cement. In the example of FIG. 2, the coarse powder B1C is charged into the clinker manufacturing facility 10, and the cement clinker Cn1 obtained from the clinker manufacturing facility 10 is mixed with gypsum as needed and crushed into the first crushing facility 30. The case of being thrown in is illustrated. In the latter case, the coarse powder B1C is pulverized together with the cement clinker Cn1 to produce mixed cement. At that time, watering and crushing aids are added as needed. However, the coarse powder B1C may be charged into either the clinker production facility 10 or the first crushing facility 30.

As the first crushing equipment 30, a general mill used in the finishing process such as a tube mill can be used. The mill is also called a finish crusher, and in a cylindrical drum, a steel ball, cement clinker Cn1, and gypsum added as needed are crushed while colliding with each other by the rotation of the drum. When gypsum is used, the gypsum is not particularly limited, and examples thereof include natural dihydrate gypsum, flue gas desulfurized gypsum, phosphoric acid gypsum, titanium gypsum, and phosphoric acid gypsum. These may be used alone or in combination of two or more.

The crude powder B1C replaces a part of the cement raw material, and it is preferable to add 0.5% by mass to 30% by mass with respect to the mass of the cement raw material. Further, it is preferable to add gypsum in an SO ₃ equivalent of 1.5% by mass to 5.0% by mass in order to improve the strength development and fluidity of the cement.

As another method, the coarse powder B1C obtained in the classification step S10 may be directly charged into the clinker cooler 13. Examples of the charging method include a method of dropping from the upper part of the clinker cooler 13 at a position of a desired temperature in the clinker cooler 13. The input amount is preferably set to be about 0.5% by mass to 20% by mass with respect to the mass of the cement. If an air-quenching cooler is used as the clinker cooler 13, the coarse powder B1C can be charged at a predetermined position in the clinker cooler 13, which is preferable.

When the coarse powder B1C is washed with water and then put into the clinker cooler 13, it is convenient because the water can be evaporated and removed by using heat energy which is not directly related to the production of the cement clinker Cn1. Further, in order to prevent a large amount of dust from being generated in the clinker cooler 13, the coarse powder B1C preferably has a water content of 50% by mass or less, and is preferably added in the form of lumps or granules.

The crude powder B1C obtained after the classification step S10 is also reduced in alkali metal concentration, calcium concentration, chlorine concentration, and sulfur concentration as compared with the fine powder B1F. Therefore, as shown in FIG. 2, it can be used in the clinker manufacturing facility 10 together with the cement clinker raw material Y1. For example, in the clinker manufacturing facility 10, it is possible to put the cement clinker raw material Y1 into a mixer for preparation, put it into a preheater 11 or a calcination furnace, put the cement kiln 12 into a kiln butt or a kiln front, and the like. It can be suitably used as a raw material for cement clinker Cn1 that can be put into various cement manufacturing stages.

As another example, as shown in FIG. 4, even if the processing system 1 is provided with a crushing facility (second crushing facility 35) different from the first crushing facility 30 for crushing the cement clinker Cn1. I do not care. The coarse powder B1C classified in the classification facility 20 may be crushed in the second crushing facility 35 and then charged into the clinker cooler 13 or the first crushing facility 30. The second crushing equipment 35 can be realized by the same equipment as the first crushing equipment 30. The step of crushing the coarse powder B1C in the second crushing facility 35 corresponds to the step (c). The strength of cement is enhanced by putting it into a cement clinker or cement in a state where the particle size is made finer by crushing.

Further, the coarse powder B1C after crushing may be mixed with the cement obtained after the cement clinker Cn1 is crushed in the first crushing equipment 30. The timing of this mixing may be on the route to the cement silo in which the cement is stored in the subsequent stage of the first crushing facility 30, may be in the cement silo, and further, when the cement is used. It does not matter even during the cement mixing process. Since the crude powder B1C has a low chlorine content, the effect of suppressing an increase in the chlorine content of the hardened cement product can be obtained while using the biomass ash B1 regardless of the timing of mixing the crude powder B1C.

The crude powder ^{B1C is preferably pulverized so that the specific surface area of the brain is 4000 cm 2} ^/ g or more in order to activate the pozzolan reaction and increase the strength of the hardened cement product. It is particularly preferable to do so. The activity index of the coarse powder B1C after pulverization is higher than that of biomass ash (raw ash) B1, typically 65% or more in 7 days, 70% or more in 28 days, and more typically. It will be 68% or more in 7 days and 70% or more in 28 days.

Further, as described above, the chlorine concentration of the crude powder B1C is greatly reduced by the classification step S10, and the sulfur content is also greatly reduced, so that clogging due to the adhesion of the low melting point substance to the preheater, the kiln bottom, and the kiln is suppressed. To. Further, the coarse powder B1C in a state where the reactivity is enhanced by being crushed by the second crushing equipment 35 may be used as a cement mixture.

As described above, the step S20 in which the coarse powder B1C after classification or the coarse powder B1C after pulverization treatment is put into the cement manufacturing process corresponds to the step (b).

In the processing system 1 of the present embodiment, the use of the fine powder B1F classified in the classification facility 20 is not restricted. For example, as will be described later, like the coarse powder B1C, it may be used as a raw material for cement clinker, or may be added (added) to cement clinker or cement as a mixed material, and may be used as fertilizer or fine aggregate. It doesn't matter if it is a thing. In particular, the fine powder B1F has a finer particle size and exhibits higher reactivity than the coarse powder B1C. Therefore, by recovering the fine powder B1F and using it as a cement mixture, the pozzolan reaction is activated and the cement cured product is obtained. The effect of increasing the strength is expected. When the obtained fine powder B1F is directly added to the same place as the coarse powder B1C at the same amount ratio, it is the same as adding the raw powder of biomass ash (raw ash B1). Therefore, taking advantage of the different characteristics such as the chemical composition of the classified biomass ash (that is, coarse powder B1C and fine powder B1F), it is possible to put it in different places, change the amount ratio, wash it with water, etc. It may be put in after going.

[Second Embodiment]
The cement manufacturing method and the second embodiment of the cement manufacturing system will be described focusing on the parts different from the first embodiment. FIG. 5 is a drawing schematically showing a processing flow of the cement manufacturing method in the present embodiment. FIG. 6 is a drawing schematically showing an example of a detailed processing flow of the water washing step S30 described later. FIG. 7 is a block diagram schematically showing the structure of the processing system 1 that implements the cement manufacturing method of the present embodiment, following FIG. 2.

The treatment system 1 of the present embodiment shown in FIG. 7 is different from the first embodiment in that it is provided with a water washing facility 40. The water washing facility 40 is a facility for washing the biomass ash B1 with water, and is provided for the purpose of reducing the concentration of cement repellent components such as chlorine contained in the biomass ash B1. An example of the detailed structure of the water washing facility 40 will be described later with reference to FIG. The treatment system 1 in the present embodiment can also be referred to as a "cement manufacturing system" as in the first embodiment.

Note that, according to FIGS. 5 and 7, in the present embodiment, it is shown that the water washing step S30 is performed only on the fine powder B1F obtained after the classification step S10. This is because, as described above in the first embodiment, the biomass ash (raw ash) B1 is classified by the classification step S10, so that the chlorine content of the crude powder B1C is lowered, while that of the fine powder B1F is reduced. This is because the chlorine content is relatively high. However, as will be described later, the water washing step S30 may be executed for the coarse powder B1C, or the water washing step S30 may be executed together with the classification step S10. When the classification step S10 and the water washing step S30 are executed at the same time, the wet classification may be performed.

(Water washing step S30)
In the present embodiment, the fine powder B1F obtained by classifying the biomass ash (raw ash) B1 in the classification step S10 is subjected to a water washing treatment by the water washing equipment 40. More specifically, as shown in FIG. 6, a step S31 for slurrying the fine powder B1F, a step S32 for washing the slurry with water, and a step S33 for dehydrating are executed.

As an example, in the water washing facility 40 shown in FIG. 8, a powder dissolving tank 43 for adding water W2 to the fine powder B1F obtained after classification to form a slurry Lr1 and washing with water, and a powder dissolving tank 43 after washing with water It is provided with a solid-liquid separation device 46 for dehydrating the discharged slurry Lr2 and a transfer device 47 for transporting the dehydrated product Ck1 separated by the solid-liquid separation device 46.

Further, in the example of the water washing facility 40 shown in FIG. 8, a liquid supply device 42 for supplying water W2 is attached. Further, a slurry stirring device 44 equipped with a stirring blade is attached for mixing the fine powder B1F and water W2 and stirring the slurry Lr1 generated by the mixing.

In the powder dissolution tank 43, a slurrying step S31 for mixing and stirring fine powder B1F and water W2 to generate a slurry Lr1 and a water washing step S32 for eluting a cement repellent component such as chlorine into the liquid phase in the slurry Lr1 are performed. Will be done. As the slurry agitator 44 for that purpose, for example, a paddle type or screw type general agitator can be used.

The mass ratio (W2 / B1F) of the fine powder B1F and water W2 in the slurrying step S31 is preferably 2 to 10, more preferably 3 to 7, and particularly preferably 4 to 5. If the mass ratio (W2 / B1F) is smaller than 2, the reforming effect may be insufficient, such as insufficient elution of water-soluble components such as chlorine from the fine powder B1F. Further, if the mass ratio (W2 / B1F) is larger than 10, the amount of wastewater W4 becomes large.

The water washing step S32 is performed by allowing the slurry Lr1 to stand or stir for a predetermined time. As a result, slurry Lr2 in which the soluble component of the fine powder B1F is eluted in the liquid phase of the slurry can be obtained.

The time required for the water washing step S32 is preferably 30 minutes or more, more preferably 45 minutes or more, because the fine powder B1F is sufficiently reformed with water W2. The higher the temperature at the time of executing the water washing step S32, the better the elution efficiency of water-soluble components such as chlorine from the fine powder B1F, but from the viewpoint of the cost related to the treatment, the temperature should be 5 ° C to 50 ° C. Is preferable, and 25 ° C to 50 ° C is more preferable.

After the water washing step S32, the slurry Lr2 in which the cement repellent component such as chlorine is eluted in the liquid phase in the slurry is discharged from the powder dissolution tank 43 and transferred to the solid-liquid separation device 46. For the transfer of the slurry Lr2, a normal slurry liquid transport device (not shown) such as a centrifugal pump for slurry, a piston pump, and a mono pump may be used.

The solid-liquid separation device 46 separates the slurry Lr2 into solid and liquid to obtain a dehydrated product Ck1 (dehydration step S33). As the solid-liquid separation device 46, a filter press, a pressurized leaf filter device, a screw press, a belt press, a belt filter, a normal filtration device such as sedimentation separation, or the like can be used.

In the dehydration step S33, in order to prevent water-soluble components such as chlorine contained in the slurry Lr2 from remaining together with the liquid phase, the water content of the dehydrated product is preferably 20% by mass to 90% by mass, preferably 30% by mass. It is more preferably to be about 70% by mass.

Since the components eluted in the liquid phase of the slurry Lr2 are removed to the waste water W4, the amount of the cement repellent component such as chlorine is reduced in the obtained dehydrated product Ck1 as compared with the fine powder B1F before the execution of the washing step S30. Ru. On the other hand, since heavy metals and the like contained in the biomass ash B1 are also eluted in the wastewater W4, they may be discharged into the environment after being appropriately treated for water quality.

As shown in FIG. 7, a water cleaning device 49 may be attached to the solid-liquid separation device 46, and water W3 may be added to the dehydrated product Ck1 and then dehydrated again. According to this, since the liquid phase of the slurry Lr2 is almost replaced with water, the eluted components can be removed more reliably.

This water washing step S30 corresponds to the step (e).

The dehydrated product Ck1 obtained through the washing step S30 has a reduced content of cement repellent components such as chlorine, and contains easily reactive calcium oxide and calcium hydroxide that affect the strength development and fluidity of cement Cn2. Is sufficiently reduced. Therefore, the quality of the cement Cn2 obtained by using the dehydrated anhydride Ck1 derived from the fine powder B1F is uniformly added to the raw material of the cement clinker Cn1 or to the cement clinker Cn1 or the cement Cn2. It will be easier to keep. In the example of FIG. 7, an example in which the fine powder B1F after washing with water is put into the cement clinker Cn1 is shown. This step corresponds to step (d).

In particular, when the biomass ash B1 discharged from the fluidized bed type combustion furnace into which the limestone containing a calcium component is charged is used as the raw ash, the above effect can be remarkably realized.

Further, the dehydrated product Ck1 derived from the fine powder B1F obtained through the washing step S30 may contain water as compared with the fine powder B1F obtained in the first embodiment. Therefore, by putting this dehydrated product Ck1 into the first crushing equipment 30, it can also be used for temperature control in the first crushing equipment 30. If the water content in the dehydrated product Ck1 is excessive, it can be easily dehydrated by sedimentation separation or the like, and conversely, if the water content is insufficient, an appropriate amount is sprinkled on the first crushing facility 30. Just do it.

The wastewater W4 obtained in the dehydration step S33 may be mixed with cement clinker Cn1 in a state where the contained chlorine ions are reduced by a well-known method such as ion exchange resin, membrane separation, and precipitation formation by silver or lead ions. This makes it possible to effectively utilize the alkali metal contained in the wastewater W4, which has a strength-enhancing effect, while removing chlorine that causes corrosion of the reinforcing bars. As in the present embodiment, the dehydrated product Ck1 derived from the fine powder B1F obtained by executing the water washing step S30 becomes less active by washing with water. Therefore, the activity is increased by adding the waste water W4 after washing with water as a cement additive. Can be compensated for.

Biomass ash B1 has a lower chlorine content than municipal waste incinerator ash. Therefore, the chlorine contained in the wastewater W4 can be easily separated, and a large amount of alkali metal sulfates and carbonates can be obtained in the wastewater W4. Therefore, by charging the wastewater W4 on the route from the clinker cooler 13 to the first crushing facility 30, more alkali metals can be utilized as the cement additive.

By inputting the wastewater W4 on the route from the clinker cooler 13 to the first crushing facility 30, water for cooling the cement clinker Cn1 and for adjusting the temperature in the first crushing facility 30 can be sprinkled without drying or solidifying. It can also be used. More specific charging points include a clinker cooler 13 having a temperature of 400 ° C. or lower in the clinker manufacturing facility 10, a transport device for transporting from the clinker cooler 13 to a subsequent stage, and a first crushing facility 30. When the temperature of the charging point exceeds 400 ° C., it evaporates instantly, so that the alkali metal as a cement additive is less likely to be contained in the cement Cn2. Further, if the wastewater W4 is introduced after the first crushing facility 30, water remains in the cement Cn2, and the quality may deteriorate due to the influence of weathering and hydration.

The wastewater W4 may be drained between the clinker cooler 13 and the first crushing facility 30 in a state where the water content has been reduced by performing a drying treatment or the like. According to this, more alkali metals can be utilized as a cement additive without weathering the cement Cn2. In particular, if the wastewater W4 is dried and solidified, it can be added to the cement Cn2 obtained after crushing in the first crushing facility 30, or can be added to the kneading step at the time of manufacturing the cement kneaded body. Therefore, any amount can be easily added.

As a means for reducing the contained chlorine ions, an amphoteric ion exchange resin or a nanofiltration membrane is particularly preferable. According to this, sulfate ion / carbonate ion and chlorine ion can be selectively separated, and water having a high sulfate ion / carbonate ion concentration and a low chlorine ion concentration and water having a low sulfate ion / carbonate ion concentration and a chlorine ion can be separated. Highly concentrated water can be obtained.

The wastewater W4 obtained after washing the fine powder B1F with water often contains selenium and hexavalent chromium. By using the above-mentioned amphoteric ion exchange resin and nanofiltration membrane, selenium and hexavalent chromium, which have the same morphology as sulfate ions, are separated on the water side with a low chlorine concentration. Water with a high chlorine concentration is disposed of, but the water has a low concentration of selenium and hexavalent chromium, which facilitates wastewater treatment. In addition, the amount of water can be reduced (increasing the concentration of alkali metal) without drying, and when charged between the clinker cooler 13 and the first crushing facility 30, more alkali metal can be used as a cement additive with the same amount of water sprinkled. Can be utilized.

As described above, both the wastewater W4 (cement additive) obtained from the washing water and the dehydrated product Ck1 obtained after washing the fine powder B1F with water can be used in the manufacturing process of the cement Cn2. Further, as described above in the first embodiment, the crude powder B1C can also be used as a raw material for cement clinker or as a mixed material for cement clinker or cement. That is, according to the present embodiment, the biomass ash B1 can be fully utilized for the production of cement Cn2. In addition, the effect of reducing the amount of wastewater to be disposed of and the load of wastewater treatment can be expected.

In the present embodiment, it is also possible to execute the oxidation step S41 and the unburned carbon removing step S42 together with the water washing step S30 (see FIGS. 9 and 10). These steps may be performed in parallel with the execution of the water washing step S30, or may be performed after the execution of the water washing step S30. In addition, only one of the oxidation step S41 and the unburned carbon removal step S42 may be performed.

FIG. 9 is a drawing schematically showing a processing flow when both the oxidation step S41 and the unburned carbon removing step S42 are executed in the present embodiment. FIG. 10 is a drawing schematically showing the structure of the water washing facility 40 when these steps S41 and S42 are executed, following FIG. 8. Note that FIG. 10 shows the gas supply device 51 and the flotation device 53 as well as the water washing facility 40.

(Oxidation step S41)
The oxidation step S41 is a step of oxidizing the fine powder B1F. As an example, in the washing step S30, it can be carried out by adding a pH adjuster to the powder dissolving tank 43 and washing with water. As a result, the washing step S30 and the oxidizing step S41 are performed in parallel.

By reducing the pH at the time of washing with water, chlorine contained in the fine powder B1F can be water-soluble more efficiently than when the pH is not adjusted. In addition, the calcium component contained in the fine powder B1F can be easily changed into the form of slow-reactive calcium carbonate or calcium sulfate added to the cement clinker Cn1 during the production of the cement Cn2. As a result, the dehydrated product Ck1 derived from the fine powder B1F obtained after the washing step S30 is suitable as a cement mixed material having a small quality variation.

The pH condition of the slurry Lr1 in the oxidation step S41 is preferably pH 4 to 13, and more preferably pH 5 to 12.

The pH adjuster is not particularly limited as long as it can reduce the pH of the slurry Lr1, and examples thereof include an acid solution such as sulfuric acid and a _CO2 -containing gas. As the CO2 _- containing gas, the combustion exhaust gas of the cement kiln 12 and the combustion exhaust gas of a biomass incineration facility or a biomass power plant can be used. Since these exhaust gases contain carbon dioxide ( _CO2 ), the pH can be adjusted from neutral to weakly alkaline by blowing the combustion exhaust gas into the slurry Lr1. According to this, the calcium component contained in the fine powder B1F is carbonated, and it becomes easier to react with the form of calcium carbonate.

In FIG. 10, as an example, a case where the _CO2 -containing gas G1 is supplied from the gas supply device 51 to the slurry Lr1 in the powder dissolution tank 43 is shown. In this case, the gas supply device 51 corresponds to the above-mentioned device for supplying the combustion exhaust gas of the cement kiln 12, the combustion exhaust gas of the biomass incineration facility, the biomass power plant, and the like to the powder melting tank 43.

The CO2 _- containing gas G1 may contain carbon dioxide, but in order to promote efficient carbonation, the carbon dioxide concentration is preferably 10% or more, more preferably 20% or more. In addition, among the combustion exhaust gas, the gas after collecting the chlorine bypass dust of the clinker manufacturing facility 10 contains harmful gas such as sulfur oxide (SO _x ), so by blowing this gas into the slurry Lr1. , The effect of immobilizing sulfur oxides can also be expected.

By using the combustion exhaust gas of the clinker production facility 10 in this way, the combustion exhaust gas containing carbon dioxide can be obtained on the spot and used for reforming the fine powder B1F, and the reformed fine powder B1F (dehydrated product Ck1) can be obtained. It can be used as a cement mixture. Further, if the combustion exhaust gas of the biomass incineration facility or the biomass power plant is used, the fine powder B1F can be reformed by using the combustion exhaust gas containing carbon dioxide obtained on the spot, and this can be reformed by the clinker production facility 10 or the first crushing. If it is transported to equipment 30 or the like, it can be immediately used as a cement mixture.

Further, in the water washing step S30, the waste liquid obtained from the amine-based carbon dioxide recovery device may be added to the powder dissolution tank 43 and washed with water. In an amine-based carbon dioxide recovery device for recovering carbon dioxide from exhaust gas of a factory or the like, a liquid containing deteriorated amines is usually discarded, but according to this method, the waste liquid can be effectively utilized.

Amines are known to have the effect of promoting the production of carbonate ions by reacting with carbon dioxide, and can efficiently promote the carbonation of calcium components. It is also known that amines function as a pulverizing aid when pulverizing cement clinker Cn1 in the first pulverizing equipment 30. The amines have an amino group and a hydroxyl group in the molecule, and in particular, the amines used as a grinding aid include, for example, monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine. (TEA), diglycolamine (DGA), diisopropanolamine (DIPA), methyldiethanolamine (MDEA), triisopropanolamine (TIPA) and the like can be mentioned. Therefore, the dehydrated Ck1 derived from the fine powder B1F in the state where the amines brought in from the added waste liquid are taken in can be expected to impart functionality as a pulverizing aid in the subsequent process, and thus can be used as a cement mixture. It becomes suitable.

The dehydrated product Ck1 obtained through the dehydration step S33 may be blown with the _CO2 -containing gas G1. According to this, since the easily reactive calcium component remaining in the dehydrated product Ck1 is carbonated, it is possible to further enhance the homogenization of the quality of the cement Cn2 produced by using the dehydrated product Ck1. can. Further, according to this method, the effect of drying the water contained in the dehydrated product Ck1 is also expected.

As the gas blowing means (gas supply device 51), any method may be used as long as the dehydrated anhydride Ck1 can be brought into contact with the _CO2 -containing gas. For example, means such as circulating the _CO2 -containing gas in a container filled with the dehydrated product Ck1 or passing the dehydrated product Ck1 through the exhaust gas flue can be used. Further, similarly to the above-mentioned blowing into the slurry Lr1, the combustion exhaust gas of the cement kiln 12 or the combustion exhaust gas of the biomass incineration facility or the biomass power plant may be blown into the dehydrated product Ck1.

This oxidation step S41 corresponds to the step (f).

(Unburned carbon removal step S42)
The unburned carbon removing step S42 is a step of removing unburned carbon contained in the fine powder B1F. As described above, the fine powder B1F obtained after classification has a high ignition loss as compared with the coarse powder B1C and contains a large amount of unburned carbon. Therefore, when the fine powder B1F is used as a raw material for the cement clinker Cn1, the temperature of the preheater 11 may increase, and when it is used as a mixed material, the concrete may darken or the fluidity may decrease. be.

Specifically, at the time of executing the washing step S30, stirring or the like is performed with the deburned carbon agent D1 such as oil or a surfactant added from the deburned carbon agent supply device 52 into the powder dissolution tank 43. A method of processing can be adopted. The obtained slurry Lr2a is subjected to a flotation treatment by adding a predetermined foaming agent, for example, in a flotation apparatus 53 to form a floss containing unburned carbon and a tail from which unburned carbon has been removed or reduced. Be separated. Then, the slurry Lr2b as a tail is sent to the solid-liquid separation device 46 for solid-liquid separation.

As a result, the washing step S30 and the unburned carbon removing step S42 are performed in parallel and continuously.

By executing the water washing step S30, the chlorine concentration (chlorine content) contained in the fine powder B1F is typically reduced to, for example, 0.01% by mass to 0.2% by mass, and more typically. It is reduced from 0.02% by mass to 0.1% by mass.

By executing the water washing step S30, the total alkali metal concentration contained in the fine powder B1F is typically reduced to, for example, 1% by mass to 8% by mass, and more typically 3% by mass to 6% by mass. Is reduced to.

By executing the water washing step S30, the sulfur oxide concentration contained in the fine powder B1F is typically reduced to, for example, 0.5% by mass to 4% by mass, and more typically 1% by mass to 3%. It is reduced to mass%.

By executing the washing step S30, the elution amount of selenium (Se) of the fine powder B1F is typically 0.002 mg / L to 0.02 mg / L, and more typically 0.005 mg / L. It is reduced to ~ 0.01 mg / L. The amount of hexavalent chromium (Cr ⁶⁺ ) eluted from the fine powder B1F is typically 0.01 mg / L to 0.1 mg / L, more typically 0.02 mg / L to 0.05 mg / L. It is reduced to L. The elution amount of these selenium and hexavalent chromium can be measured by a well-known method. As a suitable example of the measurement method, after preparing the test solution in accordance with JISK 0058-1 "Test method for chemical substances of slag-Part 1: Dissolution test method 5. Test by actual use", for selenium Examples thereof include a method of measuring hexavalent chromium by the ICP mass analysis method and a method of measuring the hexavalent chromium by the diphenylcarbazide absorptiometry method.

Although the alkali metal content of the dehydrated product Ck1 derived from the fine powder B1F obtained by the method of the present embodiment is reduced by executing the washing step S30, the alkali metal content is still higher than that of coal ash. It is expected to be high. Therefore, when the dehydrated product Ck1 is used as a raw material for the cement clinker Cn1, cement Cn2 having a high alkali metal content may be produced. The main component of the cement additive obtained from the wastewater W4 is an alkali metal salt. Therefore, if these are contained in a large amount in concrete (cement kneaded body), an alkali-silica reaction may occur depending on the aggregate (CA, FA) used.

Therefore, when the dehydrated product Ck1 derived from fine powder B1F is added in the cement Cn2 manufacturing process, latent hydraulic substances such as blast furnace slag, fly ash, volcanic ash, and volcanic rock are used to reduce the possibility of alkali silica reaction. , Pozzolan substances such as calcined clay may also be added (added) as a cement mixture or a concrete admixture. It should be noted that such addition (addition) of a latent hydraulic substance or a pozzolan substance can also be applied to the case where the fine powder B1F in which the water washing step S30 has not been carried out is used.

(Modification example)
In this embodiment, some variations are possible.

<1> As shown in FIG. 11, the fine powder B1F after being washed with water in the water washing equipment 40 is charged into the clinker manufacturing equipment 10, and the coarse powder B1C is charged into the clinker manufacturing equipment 10 or the first crushing equipment 30. It doesn't matter.

<2> As shown in FIG. 12, of the coarse powder B1C and the fine powder B1F obtained by classifying the biomass ash B1 in the classification equipment 20, the coarse powder B1C is to be washed with water by the water washing equipment 40. It doesn't matter. The content concentrations of chlorine and sulfur in the crude powder B1C are reduced by the classification step S10, but these concentrations are further reduced by performing the washing step S30. Therefore, it can be used as a raw material for cement clinker Cn1. As shown in FIG. 12, the crude powder B1C after the washing treatment may be added to the clinker production facility 10 and charged into the first crushing facility 30. Further, as in the example shown in FIG. 4, the coarse powder B1C after the washing treatment may be crushed by the second crushing facility 35 and then charged into the clinker manufacturing facility 10.

In the embodiment shown in FIG. 12, the contents related to the water washing step S30 described above with reference to FIGS. 8 to 10 are similarly described after the description regarding the fine powder B1F is replaced with the description regarding the coarse powder B1C.

The wastewater W4 obtained in the water washing step S30 was originally obtained after washing with water for the coarse powder B1C having a small amount of chlorine, so that the chlorine content is low. Therefore, the waste water W4 may be mixed with the cement clinker Cn1 without taking measures for reducing the contained chlorine ions as described above.

On the other hand, the fine powder B1F may be mixed with cement clinker Cn1 or cement after being separately washed with water as necessary, or may be used as fertilizer or fine aggregate. do not have.

<3> In the present embodiment, it is assumed that the washing step S30 is executed after the biomass ash (raw ash B1) is classified. However, the classification step S10 may be executed after the water washing step S30 is performed on the raw ash B1 or at the same time as the water washing step S30. FIG. 13 is a drawing schematically showing a processing flow of a modified example of the cement manufacturing method in the present embodiment. Further, FIG. 14 is a block diagram schematically showing the configuration of a treatment system for carrying out the cement manufacturing method based on the treatment flow shown in FIG. 13, following FIG. 7.

In the embodiment shown in FIG. 14, the contents related to the water washing step S30 described above with reference to FIGS. 8 to 10 will be similarly described after the description regarding the fine powder B1F is replaced with the description regarding the raw ash B1.

The water washing step S30 and the classification step S10 may be performed simultaneously by the wet classifying machine. Specific examples thereof include methods such as water sieving, liquid cyclone, and centrifugation.

[Third Embodiment]
The cement manufacturing method, the cement kneaded body manufacturing method, and the third embodiment of the biomass ash powder granules according to the present invention will be described focusing on the parts different from the above embodiments. FIG. 15 is a drawing schematically showing a processing flow of a method for producing cement and a cement kneaded body in the present embodiment. FIG. 16 is a block diagram schematically showing the structure of a system that implements this manufacturing method.

The processing system 1 shown in FIG. 16 includes a raw material tank 3 in which the cement clinker raw material Y1 is stored, a powder storage tank 5 in which the biomass ash B1 is stored, a clinker production facility 10, a classification facility 20, and a first crushing facility. 30 and mixing equipment 33 are provided.

In the present embodiment, after the biomass ash (raw ash) B1 is classified, it is added in the cement Cn2 manufacturing process (including the cement clinker Cn1 manufacturing process) as described later, or the cement kneaded body Cn3 is manufactured. It is expected to be introduced at. That is, the treatment system 1 in the present embodiment can also be referred to as a "cement and cement kneaded body manufacturing system".

The preferred conditions for the biomass ash B1 used in this embodiment are the same as those described above. That is, from the viewpoint of increasing the strength of the cement Cn2 or the cement kneaded body Cn3, the biomass ash B1 preferably has a particle size median diameter (D50) of 200 μm or less, more preferably 150 μm or less, and 90 μm or less. It is more preferable to have.

The mixing facility 33 is a facility for kneading cement Cn2, water W1, fine aggregate FA, and coarse aggregate CA to produce a cement kneaded body Cn3, and is composed of a known mixer. The mixing equipment 33 is installed in, for example, a concrete factory. Here, the cement kneaded body Cn3 is concrete.

As shown in FIG. 15, the production method of the present embodiment includes a step S10 for classifying the biomass ash B1, a step S20 for charging the classified fine powder B1F in the production process for cement Cn2, and a classified coarse powder B1C. S60, which is added in the manufacturing process of the cement kneaded body Cn3.

The step S10 for classifying the biomass ash B1 and the step S20 for charging the classified biomass ash (here, fine powder B1F) in the manufacturing step of the cement Cn2 are the same as those described above in the first embodiment or the second embodiment. Since it is common, detailed explanation is omitted.

(Classification step S10)
However, in the present embodiment, it is also assumed that the biomass ash (here, coarse powder B1C) obtained after classification is used as a substitute material for the fine aggregate FA. Therefore, as a guideline item for classification in the classification step S10, in addition to the contents described above in each of the above embodiments, an amorphous content rate can be mentioned.

The crude powder B1C obtained after classification typically has an amorphous content of 60% by mass or less. The amorphous content of the crude powder B1C is preferably 50% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less. The content of the amorphous substance contained in the fine powder B1F is typically 50% by mass to 80% by mass, and more typically 60% by mass to 70% by mass. That is, by this classification step S10, the coarse powder B1C having a relatively low amorphous content and the fine powder B1F having a relatively high amorphous content are separated. This point will be described later with reference to Examples.

This classification step S10 corresponds to the step (a), and the coarse powder B1C obtained in this classification step S10 corresponds to the “biomass ash powder granules”.

(Charging step S20: At the time of manufacturing cement Cn2)
The fine powder B1F obtained in the classification step S10 is added (added) to the raw material of the cement clinker Cn1 or to the cement clinker Cn1 or the cement Cn2. In the example of FIG. 16, the case where the fine powder B1F is charged into the clinker production equipment 10 and the case where the fine powder B1F is charged into the first crushing equipment 30 for producing cement Cn2 are illustrated. In the latter case, mixed cement is produced by pulverizing the fine powder B1F together with the cement clinker Cn1. At that time, watering and crushing aids are added as needed. However, the fine powder B1F may be charged into either the clinker production facility 10 or the first crushing facility 30. When all the obtained fine powder B1F is added, it is the same as adding the raw powder of biomass ash (raw ash B1) as it is. Therefore, by utilizing the difference in characteristics such as the chemical composition of the classified biomass ash (that is, coarse powder B1C and fine powder B1F), the fine powder B1F can be used as a raw material for cement clinker Cn1, a cement mixture, or a concrete admixture. It may be partially added or washed with water as described later before being added.

It should be noted that the fine powder B1F may be added after washing with water in the same manner as described above in the second embodiment. In this case, it is convenient because the water can be evaporated and removed by using the heat energy which is not directly related to the production of the cement clinker Cn1 by putting it in the clinker cooler 13. Further, in order to prevent a large amount of dust from being generated in the clinker cooler 13, the fine powder B1F preferably has a water content of 50% by mass or less, and is preferably added in the form of lumps or granules.

Although not shown in FIG. 16, fine powder B1F may be added to the cement Cn2 obtained by crushing in the first crushing equipment 30. Specifically, the timing of this charging may be on the route to the cement silo in which the cement is stored in the subsequent stage of the first crushing facility 30, or may be in the cement silo. However, more strictly speaking, the fine powder B1F is added to the cement clinker Cn1 or the first crushing equipment 30 rather than being mixed with the cement Cn2 obtained after the cement clinker Cn1 is crushed in the first crushing equipment 30. The case of charging is preferable because the particle size is finer and the reactivity is higher.

The above-mentioned charging step S20 in the cement Cn2 manufacturing process corresponds to the step (d).

(Charging step S60: At the time of manufacturing the cement kneaded body)
The coarse powder B1C obtained in the classification step S10 is added as a partial substitute material for the fine aggregate FA at the time of manufacturing the cement kneaded body Cn3 such as concrete. In the example of FIG. 16, the case where the coarse powder B1C is mixed together with the cement Cn2, the water W1, the fine aggregate FA, and the coarse aggregate CA is shown in the mixing facility 33. As the mixing equipment 33, a general mixer is used as described above.

In the production of the cement kneaded body Cn3, the substitution rate of the coarse powder B1C with respect to the fine aggregate FA is preferably 5% by mass to 40% by mass, more preferably 10% by mass to 30% by mass, and 15% by mass. It is particularly preferable to use% to 25% by mass.

As described above, the crude powder B1C separated from the biomass ash (raw ash) B1 in the classification step S10 has a low chlorine content. Therefore, even if the cement kneaded body Cn3 is mixed with the cement Cn2 as a partial substitute material for the fine aggregate FA, the amount of chlorine contained in the cement kneaded body Cn3 can be kept within the regulated value.

As described above, the coarse powder B1C separated from the biomass ash (raw ash) B1 in the classification step S10 has a relatively low amorphous content. Therefore, even if the cement kneaded body Cn3 is mixed with the cement Cn2 as a partial substitute material for the fine aggregate FA, expansion due to the alkali-silica reaction is unlikely to occur.

As described above, the crude powder B1C separated from the biomass ash (raw ash) B1 in the classification step S10 has a relatively low sulfur oxide content. Therefore, even if the cement kneaded body Cn3 is mixed with the cement Cn2 as a partial substitute material for the fine aggregate FA at the time of manufacturing, the cement kneaded body Cn3 is not promoted from the desired state, and the cement hardened product is not promoted. The quality of can be homogenized.

As described above, the crude powder B1C separated from the biomass ash (raw ash) B1 in the classification step S10 has a relatively low ignition loss and a small amount of unburned carbon. Therefore, even if the cement kneaded body Cn3 is mixed with the cement Cn2 as a partial substitute material for the fine aggregate FA, it is unlikely that the obtained hardened cement product will be darkened.

The charging step S60 in the manufacturing process of the cement kneaded body Cn3 described above corresponds to the step (g).

(Modification example)
In this embodiment, some variations are possible.

<1> As shown in FIG. 17, the fine powder B1F classified by the classification step S10 may be charged in the cement manufacturing step after the washing step S30 is executed. FIG. 18 is a block diagram schematically showing an example of the configuration of the processing system 1 that implements the flow of FIG. 17 following FIG.

Since this water washing step S30 has the same contents as those described above in the second embodiment, detailed description thereof will be omitted. It should be noted that the point that the water washing step S30 corresponds to the step (e) is also as described above.

According to this method, as in the second embodiment, both the wastewater W4 (cement additive) obtained from the washing water and the dehydrated product Ck1 obtained after washing the fine powder B1F with water are used in the process of producing the cement Cn2. Available. Further, as described above in the present embodiment, the coarse powder B1C can be used as a partial substitute material for the fine aggregate FA at the time of producing the cement kneaded body Cn3. As a result, the biomass ash B1 can be fully used in the production of cement Cn2 and cement kneaded product Cn3. In addition, the effect of reducing the amount of wastewater to be disposed of and the load of wastewater treatment can be expected.

<2> As shown in FIG. 19, a water washing step may be executed on the coarse powder B1C obtained after the classification step S10 (water washing step S30a). In this case, as shown in FIG. 20, the treatment system 1 may be provided with a water washing facility 40a for washing the coarse powder B1C after classification with water. In executing the water washing step S30a for the coarse powder B1C, the same method as the water washing step S30 for the fine powder B1F described above can be used. The dehydrated product Ck1 obtained after washing the coarse powder B1C with water is charged as a partial substitute material for the fine aggregate FA during the production of the cement kneaded product Cn3 in the charging step S60.

As described above, although the chlorine content of the coarse powder B1C is lower than that of the fine powder B1F, it is expected that the chlorine content will be further reduced by performing the washing step S30a as in this embodiment. To.

<3> In the processing flow shown in FIG. 19, the classification step S10 and the water washing step (S30, S30a) may be executed in parallel. In this case, the treatment system 1 is provided with a classification facility 20 (40) equipped with a water washing function (see FIG. 21). In this case, a wet classifier is preferably used.

Further, the raw ash (biomass ash B1) before classification may be subjected to the water washing step S30 and then the classification step S10. In this case, wet classification is adopted in the classification step S10. This point is the same in each of the above embodiments.

<4> As shown in FIG. 22, the analysis step S61 may be executed on the crude powder B1C classified by the classification step S10. FIG. 23 is a block diagram schematically showing an example of the configuration of the processing system 1 that implements the flow of FIG. 22 following FIG. The processing system 1 shown in FIG. 23 is different from FIG. 16 in that it includes an analysis facility 61 and a second crushing facility 35.

(Analysis step S61)
The crude powder B1C obtained in the classification step S10 is analyzed in the analysis facility 61, and the proportion of amorphous material is measured. This measurement may be performed on a part extracted from the obtained crude powder B1C. The analysis equipment 61 includes an X-ray diffractometer and an arithmetic processing unit, and as a measurement method, a method of calculating the measurement result of X-ray diffraction by Rietveld analysis (XRD-Rietveld method) can be preferably used.

(Crushing step S62)
As described above in the first embodiment, the crude powder B1C obtained in the classification step S10 typically has an amorphous ratio of 60% by mass or less. The proportion of the amorphous material is preferably 50% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less. However, depending on the properties of the biomass ash (raw ash) B1, the proportion of amorphous crude powder B1C obtained in the classification step S10 may be relatively high.

Based on the analysis result in the analysis step S61, when the amorphous ratio of the crude powder B1C is higher than the reference value, it is crushed by the second crushing equipment 35. The point that the second crushing equipment 35 can use the same equipment as the first crushing equipment 30 is as described above in the first embodiment.

If the coarse powder B1C having an amorphous ratio exceeding the standard value is used as a partial substitute material for the fine aggregate FA during the production of the cement kneaded body Cn3, the cement kneaded body Cn3 may cause an alkali-silica reaction. There is. On the other hand, this crude powder B1C is obtained after the biomass ash B1 is classified, and has a low content of calcium, sulfur, chlorine, and carbon, and has a composition close to that of coal ash. Therefore, it can be used as a raw material for cement clinker Cn1 or as a mixed material for manufacturing cement Cn2.

Since the coarse powder B1C has a large particle size as it is, it is crushed in the crushing step S62, and then the obtained crushed coarse powder B2C is added in the cement Cn2 manufacturing process. This crushing step S62 corresponds to the step (c), and the step S20 in which the crushed coarse powder B2C is added in the manufacturing process of the cement Cn2 corresponds to the step (b).

However, when the coarse powder B1C is put into the first crushing equipment 30, the second crushing equipment 35 is not always necessary. When the coarse powder B1C is used as a raw material for the cement clinker Cn1, the crushing facility 62 may be a raw material crusher in the clinker manufacturing facility 10.

<5> In the present embodiment, as long as the crude powder B1C obtained after classifying the biomass ash B1 is used at least during the production of the cement kneaded product Cn3, the fine powder B1F may be used for other purposes. do not have.

[Another Embodiment]
The contents of each of the above-described embodiments may be combined as appropriate.

[Verification 1]
Incinerator fly ash BA-1 (grain size D50 is 47.2 μm, ignition loss (ig.loss) at 975 ° C. is 4 from the biomass power generation facility P1 that uses palm coconut shells as fuel to generate electricity with a circulating fluidized bed furnace. .17%) was obtained (biomass ash B1), and the effect of classifying it on the composition of biomass ash was investigated. The content of coal in the mixed fuel of palm coconut shell and coal was 10% by mass. The particle size distribution of this incinerated fly ash BA-1 (laser diffraction type particle size distribution measuring device: using MT3300EX II manufactured by Microtrac Bell) is as shown in FIG.

"Test method"
The test method will be described below.

<1. Classification>
Sieve the biomass ash B1 using an open sieve (spin air sheave: SAR-75 / 200 manufactured by Seishin Enterprise Co., Ltd.) set to be the classification point shown in Table 1, and use the fine powder B1F as the sieve passing component. , Crude powder B1C was obtained as a sieve residue. This process corresponds to the classification step S10. This classification point is set based on the particle size distribution shown in FIG. In the test, biomass ash B1 was classified at three classification points of 32 μm, 45 μm, and 90 μm, respectively. In the following, in order to clarify that the biomass ash B1 is before classification, it may be referred to as "raw ash B1".

Table 1 shows the particle size distribution of biomass ash after classification. Table 1 also shows the crude powder B1C obtained after classifying the incinerated fly ash BA-2 obtained from the biomass power generation facility P2, which is different from the biomass power generation facility P1, with a classification point of 45 μm. It is shown. The particle size distribution was measured by a laser diffraction type particle size distribution measuring device (MT3300EXII manufactured by Microtrac Bell).

<2. Mineral composition analysis>
Raw ash B1 (reference numeral # 1) derived from incinerated fly ash BA-1, coarse powder B1C (reference numeral # 2) obtained by classifying raw ash B1 by 45 μm, and fine powder B1F (reference numeral # 3) obtained by classifying raw ash B1 by 45 μm. The mineral composition of the crude powder B1C (reference numeral # 6) obtained by classifying the raw ash B1 at 90 μm and the crude powder B1C (reference numeral # 8) derived from the incinerated fly ash BA-2 was measured using the XRD / Rietbelt method.

The raw ash B1 (reference numeral # 1) derived from incinerated fly ash BA-1 is further stored at 20 ° C. for 3 days after adding 20% by mass (water content 16.7% by mass) of water by external percentage. The mineral composition was measured by the same method after making a wet ash by drying at 105 ° C. This biomass ash is described as "reference numeral # 1W". Further, the mineral composition of the crude powder B1C (denoted as "reference numeral # 2W") obtained by classifying the wet ashized raw ash B1 (# 1W) by 45 μm was measured by the same method. When classifying the wet ash raw ash B1 (# 1W), an air jet sheave (manufactured by Hosokawa Micron Corporation, e200LS) was used.

First, corundum (Al ₂ O ₃ ) is internally divided as an internal standard substance for the biomass ash corresponding to each of the above codes (# 1, # 2, # 3, # 6, # 8, # 1W, # 2W). The X-ray diffraction pattern was measured by an X-ray diffractometer (D8 ADVANCE A-25 manufactured by Bruker AXS Co., Ltd.) using a sample to which 10% was added. The measurement conditions for X-ray diffraction were CuKα ray, tube voltage 50 kV, tube current 40 mA, scanning range 5 ° to 65 ° (2θ), step width 0.0234, and scanning speed 0.13 sec / step. Next, Rietveld analysis was performed using software (TOPAS Ver.6.0 manufactured by Bruker AEX Co., Ltd.) using the obtained diffraction pattern, and quantitative results of the mineral composition were obtained.

From the obtained results, the amorphous amount was calculated from the corundum quantitative value using the following formula (1).
G = 100 · (AR) / {A · (100-R) / 100} ... (1)
In the formula (1), G is an amorphous amount (%), R is a ₃ mixing ratio (%) of Al ₂ O ₃ , and A is a quantitative value (%) of Al ₂ O ₃ .

In addition, the quantification results obtained from the Rietbelt analysis were standardized so that the total amount of the composition excluding the quantified value of corundum was 100%, and then standardized at the ratio obtained by subtracting the amorphous amount from this value. The value was used as the mineral composition of each biomass ash (# 1, # 2, # 3, # 6, # 8, # 1W, # 2W).

Table 2 shows the results of the mineral composition analysis.

According to Table 2, from the comparison results of # 1 to # 3, it is confirmed that the coarse powder B1C obtained by the classification step S10 has a lower amorphous ratio than the fine powder B1F. According to the comparison results of # 1W and # 2W, it is confirmed that the coarse powder B1C obtained by the classification step S10 also has a lower amorphous ratio than the fine powder B1F in the wet ash.

Note that FIG. 24 is a polarizing microscope observation image of the raw ash B1 derived from the incinerated fly ash BA-1. Specifically, after extracting the raw ash B1 and hardening it with an epoxy resin, a chip having a size of about 20 mm × 30 mm was cut out to prepare a mirror-polished slice having a thickness of about 20 μm. The mirror-polished flakes were observed under a polarizing microscope to confirm the substances constituting the sample.

According to the image shown in FIG. 24, it is confirmed that only a part around the quartz particles is melted and vitrified (amorphized), and the coarse powder side having a relatively large particle size is confirmed. It can be seen that the proportion of amorphous contained is low.

<3. Compressive strength test, 4. Alkaline silica reaction test>
In accordance with JIS R 5201 "Physical test method for cement", ordinary Portland cement, water, and fine aggregate were mixed to produce a mortar as a specimen, and a compressive strength test was performed on this mortar. ..

In addition, in accordance with JIS A 1146 "Alkaline Silica Reactivity Test Method for Aggregate (Mortar Bar Method)", ordinary Portland cement, water, and fine aggregate were mixed to produce a mortar as a specimen. An alkali silica reactivity test was performed on this mortar.

In Comparative Example 1, only mountain sand was used as the fine aggregate. Further, in Examples 1 to 5, a part of the fine aggregate was replaced with the coarse powder B1C (# 2, # 6, # 8) of the biomass ash in Table 2 above from the mountain sand at a predetermined substitution rate. It was used. Table 3 shows the properties of the mountain sand NS used in the test. Table 4 shows the results of the compressive strength test and the alkali-silica reaction test in Examples 1 to 5 and Comparative Example 1.

According to Table 4, Examples 1 to 4 using the coarse powder B1C (# 2, # 6) derived from the incinerated fly ash BA-1 and the coarse powder B1C (# 8) derived from the incinerated fly ash BA-2 were used. In any of the 5 examples used, the result of the alkali silica reactivity test is Category A, and it is confirmed that the alkali silica reaction is unlikely to occur as in Comparative Example 1 using only the fly ash NS. This is because the amorphous ratio of any of the crude powders B1C (# 2, # 6, # 8) is suppressed to 60% by mass or less, so that the reactivity with the alkali metal is suppressed to be low. It is thought that this is the case. However, the proportion of amorphous material is relatively high in Examples 1 to 5 (48.2%), and in Example 5, the expansion rate in the mortar bar method is higher than in other Examples. ..

Further, comparing Examples 1 to 3 in which the substitution rates of the crude powder B1C (# 2) obtained by classification at the same classification point (45 μm) were changed, the compressive strength of the mortar of the specimen increased as the substitution rate increased. You can see that it has been enhanced. This is because the amount of amorphous increases within the range that does not promote the alkali-silica reaction due to the increased substitution rate, the reactivity with the cement paste increases, and the adhesion strength between the cement paste and the fine aggregate increases. It is presumed that this is due to the fact. In Example 4 in which D10 exceeds 110 μm, the expansion rate and the compressive strength are lower than those in the other examples.

<5. Chemical composition analysis>
Raw ash B1 (# 1) derived from incinerated fly ash BA-1, each coarse powder B1C (# 2, # 4), each fine powder B1F (# 3, # 5), and raw ash B1 are wet ashed ( The chemical composition was measured for each of # 1W) and the crude powder B1C (# 2W) obtained by classifying the wet ashed raw ash B1 (# 1W) at 45 μm. Further, coarse powder B1C (# 9) and fine powder B1F (# 10), which were classified by classifying the raw ash B1 with 20 μm as a classification point, were obtained, and the chemical components of these were also measured in the same manner. Further, for the raw ash B1 (# 1) and the fine powder B1F (# 3) classified by 45 μm, those which have been washed with water by the following method are prepared (# 1Wp, # 3Wp) and similarly chemicalized. The components were measured.

The method of moist ashing is as follows. Wet ash by adding 20% by mass (water content 16.7% by mass) of water to the raw ash B1 (reference numeral # 1), storing at 20 ° C for 3 days, and drying at 105 ° C. And said. The raw ash B1 moistened by this method corresponds to "reference numeral # 1W", and the crude powder B1C obtained by classifying the wet ashed raw ash # 1W corresponds to "reference numeral # 2W". .. When classifying the wet ash raw ash B1 (# 1W), an air jet sheave (manufactured by Hosokawa Micron Corporation, e200LS) was used.

The procedure for washing with water is as follows. This water washing process corresponds to step S30.
(Procedure 1) 100 g of biomass ash (B1, B1F) and 400 g of tap water were put into a beaker to make a slurry, which was stirred with a stirrer at 400 rpm for 30 minutes. At this time, when adjusting the pH by inflowing CO ₂ gas during washing with water, the flow rate was adjusted while monitoring the pH in the liquid with a pH meter.
(Procedure 2) After stopping stirring, filtration was performed using a Büchner funnel, and 400 g of tap water was further added to the obtained cake on the filter paper to wash the slurry and then recovered.
(Procedure 3) After the collected cake was naturally dried, the mass was measured and various analyzes were performed.

The obtained coarse powder was pulverized using a ball mill.

The measurement of the chemical composition was carried out by the following method.
For each prepared sample (# 1 to # 5, # 9 to # 10, # 1W, # 2W, # 1Wp, # 3Wp), a fluorescent X-ray apparatus (Rigaku, ZSX Primus II) was used. The chemical composition was measured by the calibration curve (coal ash) method. The results are shown in Table 5.

Each ignition loss was measured by a method according to JIS R5202 "Cement Chemical Analysis Method". The amount of incinerated fly ash and the amount of calcium carbonate in the obtained sample is about 600 ° C to 700 ° C when the temperature of the sample is about 50 mg in a nitrogen atmosphere and the temperature is raised to 1000 ° C at a heating rate of 20 ° C / min. The amount of decrease was calculated and calculated by the ratio of the weight reduction with the reagent (using TG-DTA2000SR manufactured by NETZSCH). As for the amount of calcium hydroxide in the incinerated fly ash and the obtained sample, the amount of heat absorption around 400 ° C. when the temperature of the sample is about 50 mg in a nitrogen atmosphere and the temperature is raised to 1000 ° C. at a heating rate of 10 ° C./min is obtained. , Determined by the ratio of weight loss with the reagent (using DSC404F3 manufactured by NETZSCH).

The amount of hydrate produced was the above-mentioned loss on ignition minus the amount of decarboxylation that volatilized from the amount of calcium carbonate. The amount of hydrate produced from the raw ash B1 was 1.8%, and that of the wet ash (# 1W) was 6.0%.

According to the results in Table 5, when the raw ash B1 which is a dry ash is classified with the peaks on the fine grain side and the peaks on the coarse grain side as the classification points when the particle size distribution is expressed in frequency, fine powder (B1F). ) Side contained most of the chlorine and sulfur components (SO ₃ ). In addition, it was confirmed that the chlorine component could be efficiently removed by washing this with water. Therefore, it can be seen that the fine powder after washing with water is particularly suitable as a cement mixture. On the other hand, it was confirmed that the crude powder B1C was able to efficiently remove the chlorine component only by classifying.

Although the amount of decrease in alkali metal on the crude powder (B1C) side obtained by classifying the raw ash is small, it contains almost no chlorine component and sulfur component, CaO is reduced and SiO ₂ is increased as compared with the raw ash. Therefore, it can be seen that the crude powder has a chemical composition close to that of coal ash and is suitable as a raw material for cement clinker.

On the other hand, when the raw ash B1 that has been moistened (# 1W) is compared with the crude powder B1C (# 2W) that has been classified by 45 μm, it is confirmed that the degree of decrease in chlorine concentration due to the classification is low. .. This is because the raw ash B1 was moistened to cause agglutination and hydration reaction, and chlorine (Cl) was incorporated into the produced hydrate, resulting in a decrease in the removal rate by classification. It is estimated to be. The wet ash of the raw ash B1 (# 1W) had a hydration reaction, and the ignition loss was increased as compared with the dry ash B1.

<6. Physical test>
For the raw ash B1 (# 1) derived from incinerated fly ash BA-1, the coarse powder B1C (# 2) and the fine powder B1F (# 3) obtained with a classification point of 45 μm, the brain specific surface area, flow value ratio, and The activity index was measured by a method according to Annex C of JIS A 6201 "Fly Ash for Concrete". Further, the coarse powder B1C (# 2) was pulverized with a mill so as to have a particle size equivalent to that of the fine powder B1F, and the brain specific surface area, flow value ratio, and activity index were measured in the same manner. The crushed product (# 2C) obtained by crushing the coarse powder B1C is a simulation of the reference numeral B2C in FIGS. 22 to 23. The measurement results are shown in Table 6.

According to Table 6, it was confirmed that when the fine powder B1F obtained by classifying the raw ash B1 was used as a mixed material, the activity index was higher than that when the raw ash B1 was used. It was clarified that the crude powder B1C can be used as a pozzolan mixture having higher reactivity than the raw ash B1 if it is pulverized until the brain specific surface area becomes 4000 cm ² / g or more. Therefore, it is suggested that the crushed coarse powder B1C having a relatively high amorphous ratio can be used as a mixed material of cement Cn2 having higher reactivity.

[Verification 2]
Fly ash (grain size D50 (frequency) 45.3 μm, ignition loss at 750 ° C) from biomass power generation facility P2 that uses woody biomass (thinned wood) as fuel to generate electricity with a circulating fluidized bed furnace. 2.3%) was obtained, and the effect of washing it with water and the presence or absence of an oxidation step (particularly a carbonation step) at the time of washing with water was examined. The washing method is the same as in Verification 1.

Table 7 below shows the level of each washing condition.

"analysis"
The obtained samples were analyzed by the following methods.
Quantification of Cl: After the sample was subjected to nitric acid decomposition treatment, it was measured by a potentiometric titration method.
Quantification of K and Na: After the sample was acid-decomposed, it was measured by ICP emission spectroscopy.
Dissolution test of Se, Cr ⁶⁺ : After preparing the test solution by the method based on JIS K 0058-1 "Test method for chemical substances of slag-Part 1: Dissolution test method 5. Test by appearance" Se was measured by the ICP mass analysis method, and Cr ⁶⁺ was measured by the diphenylcarbazide absorptiometry.
Quantification of C, Mg, Al, Si, P, S, Ca, Fe: The sample subjected to the drying treatment at 40 ° C. was measured by a fluorescent X-ray apparatus (FP method: fundamental parameter method).

The amount of calcium carbonate in the raw ash and the obtained sample decreased by about 600 ° C to 700 ° C when the temperature of the sample was raised to 1000 ° C at a heating rate of 20 ° C / min in a nitrogen atmosphere. The amount was calculated and calculated by the ratio of the weight reduction with the reagent (using TG-DTA2000SR manufactured by NETZSCH). The amount of calcium hydroxide contained in the raw ash (fly ash) and the obtained sample is around 400 ° C. when the temperature of the sample is about 50 mg in a nitrogen atmosphere and the temperature is raised to 1000 ° C. at a heating rate of 10 ° C./min. The amount of heat absorbed was determined by the ratio of the weight reduction with the reagent (using DSC404F3 manufactured by NETZSCH).

The measurement results are shown in Tables 8 and 9.

According to Table 8, most of the chlorine is effectively removed by washing the raw ash with water, and it is evaluated that there is no risk of corrosive action on the reinforcing bars, etc. after the cement is hydrohardened when used as a mixed material. It was confirmed that the allowable standard of 0.035% by mass or less was satisfied. That is, it can be seen that when the biomass ash after washing with water is classified, chlorine is hardly contained on both the fine powder side and the coarse powder side.

Further, according to Table 8, it is clear that water-soluble selenium and hexavalent chromium contained in the raw ash are also effectively removed by washing with water, and the risk of elution of heavy metals when used as a mixed material is reduced. became.

As shown in Table 9, it was clarified that this biomass ash contains SiO ₂ and CaO as main constituents and is useful as a highly reactive pozzolan mixture.

According to the results of Level 2-2, it was clarified that the CO ₂ content of the biomass ash after washing with water was increased by washing with water while blowing CO ₂ gas. Therefore, it is considered that at least a part of the component for pH adjustment was immobilized in the ash after the operation of washing with water to generate calcium carbonate. In addition, calcium hydroxide disappeared by washing with water while blowing CO ₂ gas. In Table 9, a calcium hydroxide content of less than 0.01% means below the detection limit.

Table 10 below shows the results of examining the existence form of the calcium component in the ash by the XRD method.

According to Tables 9 and 10, the presence of each Ca compound of CaO (quicklime), Ca (OH) ₂ (slaked lime), CaCO ₃ (calcium carbonate), and CaSO ₄ (plaster) as the form of calcium component in raw ash. Was confirmed. On the other hand, at level 2-1 washed with water without adjusting the pH, the presence of CaO (quick lime) disappeared, and the presence of Ca (OH) ₂ (slaked lime) was confirmed to decrease. In addition, it was confirmed that the presence of CaO (quick lime) and Ca (OH) ₂ (slaked lime) disappeared and calcium carbonate increased at level 2-2, which was washed with water under the condition of pH 9 while injecting CO ₂ gas. ..

[Verification 3]
Incinerator fly ash (grain size D50 (frequency) 20.0 μm, ignition loss at 750 ° C. (ig. Loss) 6 from a biomass power generation facility P3 that uses wood pellets and palm coconut shells as fuel to generate electricity with a stoker furnace. .1%) was obtained and the same test as the verification was performed. The results are shown in Tables 11 and 12. At level 3-2, sulfuric acid for pH adjustment is added at the time of washing with water.

According to Table 11, most of the chlorine is effectively removed by washing the raw ash with water as in Verification 2, and there is a risk of corrosive action on the reinforcing bars, etc. after the cement is water-cured when used as a mixed material. It was confirmed that it meets the permissible standard of 0.035% by mass or less, which is evaluated as not. That is, it can be seen that when the biomass ash after washing with water is classified, chlorine is hardly contained on both the fine powder side and the coarse powder side. It can be concluded that this point is the same when each of the coarse powder and the fine powder after classification is washed with water.

According to Table 12, it was clarified that this biomass ash contains SiO ₂ and CaO as main constituents and is useful as a highly reactive pozzolan mixture. Furthermore, it was clarified that the SO ₃ content was increased by adding sulfuric acid and washing with water. Therefore, it is considered that at least a part of the sulfuric acid component for pH adjustment is immobilized in the ash after the washing operation.

1: Processing system 3: Raw material tank 5: Powder storage tank 10: Cleaner manufacturing equipment 11: Preheater 12: Cement kiln 13: Cleaner cooler 20: Classification equipment 30: First crushing equipment 33: Mixing equipment 35:

Second crushing equipment

40 , 40a: Water washing equipment 42: Liquid supply device 43: Powder dissolution tank 44: Slurry stirring device 46: Solid-liquid separation device 47: Transfer device 49: Water washing device 51: Gas supply device 52: Decombustible carbon agent supply device 53: Floating beneficiation equipment 61: Analytical equipment 62: Crushing equipment B1: Biomass ash (raw ash)
B1C: Coarse powder B1F: Fine powder B2C: Crushed coarse powder CA: Coarse aggregate Ck1: Dehydrated product Cn1: Cement clinker Cn2: Cement Cn3: Cement kneaded body D1: Decombustible carbon agent FA: Fine aggregate G1: _CO2 Containing gas Lr1, Lr2, Lr2a, Lr2b: Slurry W1, W2, W3: Water W4: Drainage Y1: Cement clinker raw material

Claims

Step (a) of classifying biomass ash into coarse powder and fine powder,
The coarse powder obtained in the step (a) is applied to at least one of a cement clinker raw material to be charged into a cement kiln, a cement clinker obtained from the cement kiln, or a cement obtained by crushing the cement clinker. A cement manufacturing method comprising the step (b) of charging.
The cement manufacturing method according to claim 1, wherein the step (a) is a step of classifying with 20 μm to 100 μm as a classification point.
The cement manufacturing method according to claim 1 or 2, wherein the biomass ash is fly ash generated from a fluidized bed type combustion furnace and is dry ash.
The step (b) is characterized in that the coarse powder obtained in the step (a) is put into a cement clinker obtained from the cement kiln or the cement clinker is put into the cement after the pulverization treatment. The cement manufacturing method according to any one of claims 1 to 3.
It has the step (c) of pulverizing at least a part of the said coarse powder obtained in the said step (a), and has | said.
The step (b) is a step of putting the coarse powder after being crushed by the step (c) into a cement clinker obtained from the cement kiln or the cement clinker after the crushing treatment. The cement manufacturing method according to any one of claims 1 to 4, wherein the cement manufacturing method is characterized.
The cement manufacturing method according to any one of claims 1 to 5, further comprising a step (d) of feeding the fine powder obtained in the step (a) into the cement clinker raw material.
The step 1 or 2, wherein the step (b) is a step of putting the coarse powder obtained in the step (a) into a cement clinker raw material to be put into a cement kiln. Cement manufacturing method.
The present invention is characterized by having a step (d) of putting the fine powder obtained in the step (a) into a cement clinker obtained from the cement kiln or the cement clinker after the pulverization treatment. Item 7. The cement manufacturing method according to Item 7.
The step (e) of washing the fine powder obtained in the step (a) with water is provided.
The cement manufacturing method according to claim 6 or 8, wherein the step (d) is a step of adding the fine powder after being washed with water by the step (e).
The cement manufacturing method according to claim 9, further comprising a step (f) for oxidizing the biomass ash during or after the execution of the step (e).
Step (a) of classifying biomass ash into coarse powder and fine powder,
A method for producing a cement kneaded body, which comprises a step (g) of mixing the coarse powder obtained in the step (a) with cement and water without crushing.
At least one of a cement clinker raw material to be put into a cement kiln, a cement clinker obtained from the cement kiln, or a cement obtained after crushing the cement clinker from the fine powder obtained in the step (a). The method for producing a cement kneaded product according to claim 11, further comprising a step (d) of charging into the cement kneaded product.
Biomass ash powder granules characterized in that the cumulative volume percentage of the particle size distribution is 10% and the value (D10) is 35 μm or more.
The biomass ash powder granule according to claim 13, characterized in that it exhibits a chemical composition having a chlorine (Cl) content of 0.1% by mass or less.
The biomass ash powder granule according to claim 13 or 14, characterized in that it is used for replacement with a fine aggregate for a hardened cement product.
The biomass ash powder granule according to any one of claims 13 to 15, characterized in that the content of amorphous material is 60% by mass or less.
The biomass ash powder granule according to claim 13 or 14, which is used for partial replacement with a cement clinker raw material to be charged into a cement kiln.
The biomass ash powder granule according to claim 13 or 14, wherein the cement clinker or the cement clinker is used for partial replacement with a cement mixture to be charged into the cement after the pulverization treatment.