JP5416486B2 - Method for producing zeolite-containing cured body - Google Patents

Description

  The present invention relates to a method for producing a zeolite-containing cured body. More specifically, the present invention relates to a method for producing a zeolite-containing cured body suitable for use as a substitute for brick and precast concrete or as a building material.

  Various techniques for producing block- and column-shaped zeolite-containing hardened bodies that can be used as substitutes for concrete products have been proposed.

  For example, there has been proposed a method for producing a cured product containing zeolite by subjecting a granular material of an amorphous material containing silica and alumina to dehydration after alkali treatment and hydrothermal treatment after pressure molding (Patent Document). 1). Specifically, as a granular material of amorphous material containing silica and alumina, coal ash, rock wool or slag slag, etc., which is a waste material, is used, and this granular material is immersed in an aqueous alkali hydroxide solution for a certain period of time. (Alkaline treatment), dehydrated press treatment of the alkali-treated powder particles to remove excess alkali hydroxide aqueous solution, press forming and then hydrothermal treatment (steam curing) using an autoclave to form a block A columnar zeolite-containing cured body is produced. In addition, a calcium compound such as calcium hydroxide, calcium oxide, or calcium chloride is added to the aqueous alkali hydroxide solution used as the immersion liquid during the alkali treatment.

  In the above production method, the calcium compound is added to the aqueous alkali hydroxide solution for the following purposes. That is, the viscosity of the immersion liquid increases with an increase in the concentration of the aqueous alkali hydroxide solution used as the immersion liquid and an increase in the immersion time of the granular material in the immersion liquid. Due to this, drainage resistance increases during the dehydrating press process, and the dehydrating press process cannot sufficiently dehydrate. If sufficient dehydration is not performed, excess water remains in the pressure-molded body, the amount of voids in the zeolite-containing cured body increases, and as a result, the strength of the zeolite-containing cured body decreases. Therefore, in the above production method, a calcium compound is added to the aqueous alkali hydroxide solution for the purpose of suppressing the increase in viscosity of the immersion liquid and ensuring the strength of the zeolite-containing cured body.

  In addition, a method for producing a zeolite-containing cured body by subjecting a waste pulverized product to an alkali treatment and then dehydrating and subjecting it to hydrothermal treatment after pressure molding has been proposed (Patent Document 2). Specifically, as a granular material of amorphous material containing silica and alumina, by using a pulverized product of a specific waste material called waste insulator, calcium hydroxide is used as an aqueous solution for immersion in an alkaline treatment. Without adding a compound, the viscosity increase of the immersion liquid can be suppressed, and the strength of the zeolite-containing cured body can be ensured without adding a calcium compound as in the production method described in Patent Document 1. Is.

JP-A-9-124315 JP2001-172015

  However, even if the strength of the zeolite-containing cured product obtained by the production methods described in Patent Document 1 and Patent Document 2 is the best, the compressive strength is 30 to 35 MPa and the bending strength is only about 6 to 7 MPa. Therefore, the method for producing a zeolite-containing cured body described in Patent Document 1 and Patent Document 2 has a problem that it cannot cope with a case where a zeolite-containing cured body having a higher strength than the above is required as an alternative material for a concrete product. .

  Moreover, in the manufacturing method of the zeolite containing hardened | cured material of patent document 1 and 2, since the granular material and waste insulator of the amorphous material containing a silica and an alumina are immersed in aqueous alkali hydroxide solution, an alkali treatment is performed. There is a problem that a large amount of an aqueous alkali hydroxide solution is required and the production cost increases. Furthermore, since the excess alkali hydroxide aqueous solution is removed by the dehydration press treatment, the entire amount of the alkali hydroxide aqueous solution charged at the initial stage of production cannot be used effectively, and there is a problem in that it is wasteful. Moreover, the strength of the molded body itself is sufficient to the extent that the dehydration press and pressure molding are performed on the amorphous material containing silica and alumina and the waste insulators immersed in an alkali hydroxide aqueous solution. However, it was feared that when the hydrothermal treatment was applied, cracks and the like were generated, and the zeolite-containing cured product contained defects.

  Furthermore, in the manufacturing method described in Patent Document 1, it is necessary to add a calcium compound in order to secure the strength of the zeolite-containing cured body, and there is a problem that the manufacturing cost is further increased.

  In addition, the manufacturing method described in Patent Document 2 does not require the addition of a calcium compound, so that the manufacturing cost can be reduced. From the viewpoint of promoting the use of industrial by-products and restricting the disposal site, such as fly ash discharged in large quantities from thermal power plants, it is desirable to actively increase the proportion of effective use. There was a problem that the waste that cannot be used.

  Then, an object of this invention is to provide the method which makes it possible to manufacture a zeolite containing hardened | cured material higher intensity | strength than the zeolite containing hardened | cured material manufactured with the conventional manufacturing method.

  Moreover, an object of this invention is to provide the manufacturing method of the zeolite containing hardening body which makes it possible to hold down manufacturing cost rather than the conventional manufacturing method.

  Furthermore, the present invention provides a zeolite that can use fly ash as a raw material, which is a waste for which it is desired to actively increase the proportion of effective use, while suppressing the production cost as compared with the conventional production method. It aims at providing the manufacturing method of a containing hardening body.

In order to solve such a problem, the inventors of the present application have intensively studied and developed a novel manufacturing method that is completely different from the conventional manufacturing method of zeolite-containing cured bodies. That is, after kneading the amorphous material granular material containing silica and alumina, sodium hydroxide or potassium hydroxide and water, and integrating them as a kneaded material, the moisture and shape of the kneaded material are maintained. A new method for producing a zeolite-containing cured body has been developed, in which the kneaded material is allowed to stand and hardened, and water vapor is brought into direct contact with the hardened kneaded material. And when a zeolite containing hardened | cured material is manufactured with this novel manufacturing method, it compares with the intensity | strength of the zeolite containing hardened | cured material manufactured with the conventional manufacturing method that a compressive strength is 63.7 MPa and a bending strength is 8.8 MPa. Thus, the inventors have found that a zeolite-containing cured body having a remarkably high strength can be produced, leading to the present invention.

That is, the method for producing a zeolite-containing cured product according to the present invention comprises a powdered amorphous material containing silica and alumina, an alkali hydroxide and water, kneaded into a slurry without performing a dehydration press treatment. A first step for obtaining a lump of kneaded material, a second step for allowing the kneaded material to stand and solidify while maintaining the moisture and shape of the kneaded material, and a third step for bringing water vapor into direct contact with the solidified kneaded material seen including, it is characterized in that the alkali hydroxide is sodium hydroxide or potassium hydroxide.

  By kneading and integrating a kneaded material obtained by kneading an amorphous material granular material containing silica and alumina, alkali hydroxide and water, while maintaining the moisture and shape of the kneaded material, The strength can be improved to such an extent that shape destruction due to water vapor does not occur. Therefore, in the third step, the zeolite production reaction can proceed without causing the shape of the kneaded material to be destroyed by water vapor.

  Here, the second step is preferably performed while a physical restraining pressure is applied to the kneaded material. When the amorphous material containing silica and alumina constituting the granular material comes into contact with the alkali hydroxide, the amorphous phase is eroded. When this erosion reaction occurs in the presence of water, elution of ions such as silicon and aluminum from the amorphous phase is promoted, and regularity is obtained in the process of rearranging the eluted ions. Minerals are easily generated. By applying a physical restraining pressure to a kneaded material obtained by kneading an amorphous material granular material containing silica and alumina, an alkali hydroxide, and water, the physical restraining pressure is reduced to a zeolite type. The strength of the zeolite-containing hardened body is increased by acting to reduce the distance between crystals in the process of mineral formation.

  The third step is preferably a hydrothermal treatment under saturated vapor pressure. As described above, in the second step, the strength of the kneaded material is improved to such an extent that shape destruction due to water vapor does not occur. Therefore, even if the kneaded material is subjected to hydrothermal treatment under saturated vapor pressure, the shape may be destroyed. Absent. Therefore, it is possible to accelerate the zeolite production reaction and shorten the period of production of the zeolite-containing cured body.

  Furthermore, it is preferable to use fly ash as the granular material of amorphous material containing silica and alumina. Since the fly ash particles have a particle size distribution of 1 to 200 μm, many adhesion points can be secured between the fly ash particles. Therefore, the strength of the zeolite-containing cured body can be reliably increased.

  According to the method for producing a zeolite-containing cured body according to claim 1, as in the conventional method for producing a zeolite-containing cured body, hydroxylation is performed to immerse the amorphous material granular material containing silica and alumina. There is no need to use a large amount of an alkaline aqueous solution, and there is no need to perform a dehydration press treatment. Further, it is not necessary to add a calcium compound in order to suppress an increase in the viscosity of the immersion liquid. Therefore, it is possible to greatly reduce the manufacturing cost as compared with the conventional method for producing a zeolite-containing cured body. In addition, it is possible to produce a high-strength zeolite-containing cured product as compared with conventional production methods.

  Further, according to the method for producing a zeolite-containing cured body according to claim 2, the physical restraint pressure applied to the kneaded material in the second step reduces the distance between crystals in the process of producing the zeolitic mineral. Thus, the strength of the zeolite-containing cured body can be increased.

  Furthermore, according to the method for producing a zeolite-containing cured product according to claim 3, since the hydrothermal treatment under saturated vapor pressure is performed on the kneaded material in the third step, the zeolite formation reaction is promoted to accelerate the zeolite-containing curing. It becomes possible to shorten the period for manufacturing the body.

  In addition, according to the method for producing a zeolite-containing cured product according to claim 4, fly ash is used as the powder of amorphous material containing silica and alumina. Many adhesion points can be secured, and the strength of the zeolite-containing cured body can be reliably increased. Moreover, since fly ash can be used as a raw material, it becomes possible to promote the use of fly ash discharged in large quantities from a thermal power plant. Therefore, it becomes possible to contribute to the demand for industrial use promotion of fly ash.

It is a figure which shows the mineral species identification result by XRD when an alkali is sodium hydroxide. It is a figure which shows the mineral species identification result by XRD at the time of using alkali as potassium hydroxide. It is a figure which shows the influence which the kind of alkali hydroxide has on pore diameter distribution. It is a figure which shows the apparatus which provides the physical restraint pressure in this embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  The method for producing a zeolite-containing cured body of the present invention comprises a first step of kneading an amorphous material-containing granular material containing silica and alumina, an alkali hydroxide and water to obtain a kneaded material, A second step of allowing the kneaded material to stand and solidify while maintaining the shape and a third step of directly bringing water vapor into contact with the hardened kneaded material are included.

  First, in the first step, a kneaded material is obtained by kneading an amorphous material granular material containing silica and alumina, an alkali hydroxide and water.

  As the granular material of amorphous material containing silica and alumina used in the present invention (hereinafter also referred to simply as granular material), for example, clinker ash, cinder ash, fly ash generated from a coal-fired power plant Coal ash such as can be used. In addition, rock wool, blast furnace slag generated from steelworks, ore slag such as converter slag, and waste iron or the like processed into powder can be used. However, the granular material of the amorphous material containing silica and alumina used in the present invention is not limited to these, and the granular material of the material containing silica and alumina and being substantially amorphous. Can be used. That is, the inclusion of crystals in a range that does not hinder the production of the zeolite-containing cured product is also allowed.

  Here, it is particularly preferable to use fly ash as the amorphous material containing silica and alumina used in the present invention. Since fly ash has a particle size distribution of 1 to 200 μm, many adhesion points can be secured between the fly ash particles. Therefore, it is easy to increase the strength of the zeolite-containing cured body. In addition, by increasing the reactivity of fly ash to alkali, the amorphous phase increases in the zeolite-containing cured body, and as a result of this amorphous phase acting like an adhesive, the strength of the zeolite-containing cured body It is thought that the effect which improves is obtained. The reactivity of fly ash to alkali can be improved by increasing the fineness of fly ash. In addition, by processing coal ash other than fly ash, rock wool, slag slag, waste slag, etc. into a granular material having a particle size distribution of 1 to 200 μm, it has the same strength as when fly ash is used. It is estimated that a zeolite-containing cured product can be obtained.

  Examples of the alkali hydroxide used in the present invention include sodium hydroxide and potassium hydroxide. When sodium hydroxide is used, a zeolite-containing hardened body containing, for example, gmelinite-Na, calcite (Analcime-C), and zeolite P1 can be produced. In addition, when potassium hydroxide is used, a zeolite-containing hardened body containing, for example, merlinite, philipsite-K, chabazite-Ca can be produced. In addition, the alkali hydroxide reagent used in the present invention is not limited to a high-purity product, and an industrially inexpensive reagent can be used.

  In the present invention, the amorphous material powder containing silica and alumina, the alkali hydroxide and water are kneaded by uniformly dispersing the alkali hydroxide and water in the kneaded material to produce zeolite in the kneaded material. The reaction is carried out uniformly to produce a homogeneous zeolite-containing cured product. It is noted that the powder, alkali hydroxide and water may be added separately and kneaded, but the alkali hydroxide is dissolved in water in advance to obtain an alkali hydroxide aqueous solution, and the alkali hydroxide aqueous solution and the powder are added. It is preferable to knead the granules to obtain a kneaded material. When the alkali hydroxide is dissolved in water and then kneaded with the granular material, the alkali hydroxide and water can be easily dispersed uniformly in the kneaded material, and the kneading time can be shortened.

  The amount of water mixed with the granular material may be an amount that allows the kneaded material to be a lump and has a viscosity that does not have fluidity. For example, it is preferable to set it as 200g-300g with respect to 1000g of granular materials, and it is more preferable to set it as about 250g. If the amount of water mixed is too small, it will not be possible to knead the powder particles into one lump. On the other hand, when the amount is too large, the amount of voids generated in the zeolite-containing cured body increases, and the strength of the zeolite-containing cured body cannot be secured. In the production method of the present invention, since the amount of water with respect to the granular material is small, it is preferable to knead using a forced kneading type mixer with strong stirring power. For example, the MT series manufactured by AICOH can be used, but is not limited thereto. By this kneading step, a so-called kneaded slurry kneaded material is obtained.

In the present specification, “ensuring the strength of the zeolite-containing hardened body” means securing the strength required as an alternative material for the zeolite-containing hardened concrete member or as a building material. For example, according to the present invention, a zeolite-containing cured body having a compressive strength of 29.6 MPa (29.6 N / mm ² ) or more and a bending strength of 4 MPa (4 N / mm ² ) or more can be obtained.

  The amount of alkali hydroxide mixed with the granular material is preferably as much as possible in order to accelerate the zeolite formation reaction and increase the amount of zeolitic mineral produced. In the production method of the present invention, the alkali hydroxide is kneaded. Since it is uniformly dispersed in the material, the zeolite formation reaction can sufficiently proceed even if the amount of alkali hydroxide mixed with the powder is small. According to the experiment of the present inventor, when sodium hydroxide is used as the alkali hydroxide, the zeolite formation reaction can proceed sufficiently even if the amount of sodium hydroxide mixed is 47 g with respect to 1000 g of the granular material. It has been confirmed. In addition, when potassium hydroxide is used as the alkali hydroxide, it has been confirmed that the zeolite formation reaction proceeds sufficiently even when the amount of potassium hydroxide mixed is 44 g with respect to 1000 g of the granular material.

  Next, in the second step, the kneaded material is allowed to stand and harden while maintaining the moisture and shape of the kneaded material. By this treatment, the strength of the kneaded material can be improved to such an extent that shape destruction due to water vapor does not occur.

  Specifically, the maintenance of the moisture and shape of the kneaded material does not cause the water contained in the kneaded material to evaporate or the amount of water vapor corresponding to the evaporated amount does not destroy the shape of the kneaded material. The conditions are such that the kneaded material can be replenished. More specifically, the temperature is, for example, more than 0 ° C to 80 ° C, preferably 10 ° C to 30 ° C, more preferably 20 ° C to 25 ° C. The humidity is, for example, 20% to 90%, preferably 40% to 70%, and more preferably 50% to 60%. The processing time is appropriately determined depending on the temperature and humidity conditions. That is, if the temperature and humidity are increased, the zeolite production reaction is likely to proceed, so the period required to harden the kneaded material is shortened. On the other hand, if the temperature and humidity are lowered, the zeolite production reaction becomes difficult to proceed, so that the period required for solidifying the kneaded material becomes longer. Specifically, when the kneaded material is allowed to stand under conditions of a temperature of 20 ° C. and a humidity of 60%, the shape does not change even if the kneaded material is pushed with a finger in about 10 to 14 days, and the shape is not destroyed by water vapor. This has been confirmed by experiments of the present inventors.

  Here, in the second step, it is preferable to harden the kneaded material while applying a physical restraining pressure to the kneaded material. In addition, the physical restraint pressure said here is introduce | transduced when performing steam curing at the pressure derived from the saturated steam pressure at the time of performing steam curing at the curing temperature of 100 degreeC or more, and the curing temperature of less than 100 degreeC. In addition to the pressure derived from steam, it means the pressure applied to the kneaded material.

  When the amorphous material containing silica and alumina constituting the granular material comes into contact with the alkali hydroxide, the amorphous phase is eroded. When this erosion reaction occurs in the presence of water, elution of ions such as silicon and aluminum from the amorphous phase is promoted, and regularity is obtained in the process of rearranging the eluted ions. Minerals are easily generated. By applying a physical restraining pressure to a kneaded material obtained by kneading an amorphous material granular material containing silica and alumina, an alkali hydroxide, and water, the physical restraining pressure is reduced to a zeolite type. The strength of the zeolite-containing hardened body is increased by acting to reduce the distance between crystals in the process of mineral formation.

  The physical restraint pressure can be applied by, for example, the restraint pressure applying device 1 shown in FIG. This apparatus is roughly divided into a mold 2 that contains the kneaded material 6, an upper lid 5 that covers the opening of the mold 2, and an inner lid 3 that is accommodated between the kneaded material 6 and the upper lid 5. Composed. The kneaded material 6 is defoamed and compacted after it is accommodated in the mold 2 and the inner lid 3 is closed.

  The material of the mold 2, the inner lid 3, and the upper lid 5 is, for example, stainless steel, but is not limited thereto as long as the material has alkali resistance.

  The physical restraint pressure is controlled as follows, for example. That is, the inner lid 3 is provided with a spring 4, and the unloaded position of the spring 4 (position in a state where no force is applied to the spring 4) is set higher than the height of the inner lid 3. . Then, when the upper lid 5 is fixed to the mold 2, the spring 4 can be contracted by the upper lid 5. By configuring in this manner, the spring constant of the spring 4 itself, the bottom area of the inner lid 3 (the area of the kneaded material and the grounding surface of the inner lid 3), and the deviation of the spring 4 from the unloaded position, The physical restraining pressure applied to the kneaded material 6 can be controlled.

  Further, the deviation of the spring 4 from the unloaded position can be controlled by a method other than the above method, and is not limited to applying a physical restraining pressure by the above method. For example, in this embodiment, the spring 4 is fixed to the bottom surface of the inner lid 3, and the upper surface of the inner lid 3 is used as an opening surface, and the spring 4 is projected from the opening surface. The spring 4 may be fixed to the upper surface instead of the surface. In this case, since the spring 4 can be contracted compared to the case of the present embodiment, the displacement of the spring 4 from the unloaded position can be made larger than in the case of the present embodiment, and the stronger physical A constraining pressure can be applied. That is, when springs having the same spring constant are used, the physical restraint pressure can be increased by increasing the displacement of the spring 4 from the unloaded position, and conversely, when the spring 4 is unloaded. By reducing the deviation from the position, the physical restraining pressure can be reduced.

  Moreover, it is not limited to the application method of the physical restraint pressure using the above springs. For example, the kneading material may be accommodated in a container, and a physical restraining pressure may be applied by fixing the kneading material to the container in a state where the kneading material is pressed with the lid. The method of fixing the upper lid 5 to the mold 2 is, for example, screw tightening. However, the method is not limited to this method, and the upper lid 5 is fixed to the mold 2 using a band-type fixture. It may be.

  Further, the shape of the mold 2 is not limited to the shape of the rectangular parallelepiped shown in FIG. 4 and may be, for example, a cylindrical shape.

  The value of the physical restraining pressure is not particularly limited as long as it is a value that acts to reduce the distance between crystals in the production process of the zeolitic mineral in the kneaded material. The pressure is preferably set to 02 to 0.3 MPa. Even if the restraining pressure is increased too much, the action of reducing the distance between crystals in the process of producing the zeolitic mineral is considered to be saturated.

  Here, when the kneaded material is hardened while applying a physical restraint pressure to the kneaded material by the restraint pressure applying device 1 shown in FIG. 4, the moisture and the shape of the kneaded material are maintained inside the device 1. Become. That is, in the case where accommodation of the kneaded material 6 in a completely sealed state is achievable, water contained in the kneaded material 6 does not leak out of the apparatus 1, and the amount of water vapor is so large that the shape is destroyed. The kneaded material 6 is not exposed. Further, even when the restraint pressure applying device 1 shown in FIG. 4 is in a substantially sealed state, there is almost no possibility that water contained in the kneading material 6 leaks out of the device 1 and the kneading material 6 is dried, and its shape As a result, the kneaded material 6 is not exposed to a large amount of water vapor so as to be destroyed. That is, the restraint pressure applying device 1 shown in FIG. 4 not only facilitates increasing the strength of the zeolite-containing cured body, but also suppresses the release of moisture from the kneaded material. Therefore, in addition to the above temperature range of more than 0 ° C. to 80 ° C., it is also possible to heat at a temperature higher than 80 ° C. (for example, 80 to 100 ° C.). There is also an advantage that it can be. For example, when the apparatus 1 is heated at 80 ° C., the kneaded material is sufficiently hardened in about 1 to 2 days. Therefore, it is possible to shorten the time necessary for further solidifying the kneaded material by raising the temperature. Here, the gap in the substantially sealed state is a gap where excessive moisture is supplied to the kneaded material and the shape thereof is not destroyed, specifically, the container containing the kneaded material and the periphery of the lid of the container Or a gap of several millimeters between the container containing the kneaded material and the corners of the lid of the container (for example, the four corners of the lid when the container is a rectangular parallelepiped). .

  The kneaded material is hardened while being applied with a physical restraining pressure by the restraining pressure applying device 1 shown in FIG. 4, and then taken out from the device 1 and used for the third step.

  In the third step, the kneaded material is brought into direct contact with water vapor.

  The shape of the kneaded material hardened in the second step is not destroyed by water vapor. Therefore, even when exposed to saturated vapor pressure, the shape is not destroyed, and hydrothermal treatment under saturated vapor pressure suitable for accelerating the zeolite formation reaction is performed using, for example, a steam autoclave apparatus, and the zeolite-containing cured product is converted into a short-term. It becomes possible to manufacture in between. However, the third step is not limited to hydrothermal treatment under saturated vapor pressure. That is, if it is allowed to stand for a long period of time under the same conditions as in the second step, it is possible to produce a zeolite-containing cured body, so the same conditions as in the second step, that is, the moisture and shape of the kneaded material. The kneaded material may be brought into contact with water vapor under a condition that can maintain the heat resistance, for example, water vapor present in the atmosphere. For example, if it is allowed to stand for 2 to 3 months in an environment of a temperature of 20 ° C. and a humidity of 60%, it is possible to produce a zeolite-containing cured product. Therefore, when it is desired to produce a zeolite-containing cured product in a short period of time, the third step may be performed under hydrothermal treatment under saturated vapor pressure or a condition close thereto, and the period required for production of the zeolite-containing cured product may be increased. If there is no particular problem even if it is a long period of time, and it is desired to focus on reducing the production cost, it is preferable that the zeolite formation reaction proceeds under mild conditions (for example, temperature 20 ° C., humidity 60%). You may make it perform a 3rd process on the conditions which maintain the conditions of a process as it is.

  The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without departing from the scope of the present invention. For example, in the above-described embodiment, the case where the second step is performed while applying the physical restraint pressure to the kneaded material by the physical restraint pressure applying device 1 illustrated in FIG. 4 has been described as an example. The kneaded material may simply be accommodated by the physical restraint pressure applying device 1 shown in FIG. 5 and the second step may be performed without applying a physical restraint pressure to the kneaded material. Also in this case, the moisture and shape of the kneaded material are maintained in the apparatus 1, and in addition to over 0 ° C. to 80 ° C., heating is performed at a temperature higher than 80 ° C. (for example, 80 to 100 ° C.). Even so, the moisture of the kneaded material is maintained. Therefore, it is possible to obtain a benefit due to the advantage that the period necessary for solidifying the kneaded material can be shortened.

  The kneaded material may be further kneaded with reinforcing fibers as long as the progress of zeolite production of the kneaded material is not hindered. In this case, both the compressive strength and bending strength of the zeolite-containing cured body can be increased, and in particular, there is an effect of remarkably improving the bending strength. As the reinforcing fiber, steel fiber, polypropylene fiber, or the like can be used, but is not limited thereto. Further, the amount of the reinforcing fiber mixed with the granular material is not particularly limited as long as it does not impede the production of the zeolite-containing cured body. For example, if 30 g of the reinforcing fiber is mixed with 1000 g of the granular material, The effect of increasing the strength of the cured body is sufficiently exhibited.

  Examples of the method for producing a zeolite-containing cured body of the present invention will be described below, but the present invention is not limited to these examples.

(1) Blending conditions of powder material, alkali hydroxide, and mixed water Fly ash corresponding to type II in JIS A 6201 was used as a powder particle. The loss on ignition of this fly ash was 2.9% by weight. The SiO ₂ content was 53.9% by weight, and the CaO content was 7.2% by weight. Sodium hydroxide (Wako Pure Chemical) or potassium hydroxide (Wako Pure Chemical) was used as the alkali hydroxide. Tap water was used as mixing water. The alkali hydroxide was dissolved in water and used as an alkali hydroxide solution.

  In the present Example, the compounding 1-6 shown in Table 1 and the compounding 7-13 shown in Table 2 were set as the compounding conditions of a zeolite containing hardening body manufacturing raw material. In the formulation shown in Table 1, sodium hydroxide was used as the alkali hydroxide, and in the formulation shown in Table 2, potassium hydroxide was used as the alkali hydroxide. The units in Tables 1 and 2 are all “g”, and the NaOH addition rate and the KOH addition rate are expressed as a mass ratio of alkali hydroxide to fly ash in%.

(2) Manufacturing conditions for zeolite-containing cured body According to the formulation shown in Tables 1 and 2, each material was weighed with 1400 g of fly ash, and an aqueous alkali hydroxide solution was added to the fly ash to produce a forced kneading mixer with strong stirring power. Kneaded homogeneously (MT series manufactured by AICOH) to obtain a kneaded material. This mixer has two stirrers that move in a planetary motion, and by mixing for about 5 minutes, a homogeneous kneaded material could be obtained.

Next, this kneaded material is placed in a general mold without a lid (4 × 4 × 16 cm per piece, triple mold for mortar test) and placed in a room (temperature 20 ° C., humidity 60 ° C.). It was allowed to stand for a week and hardened to such an extent that its shape did not change when pressed with a finger (compressive strength 3N / mm ² ). In addition, when this kneaded material was directly put into a steam autoclave apparatus and processed without performing this treatment, the kneaded material was flowed into the vapor in the process, and its shape could not be maintained.

  The kneaded material that had been allowed to stand for 2 weeks was placed in a steam autoclave and hydrothermally treated under general curing conditions (220 ° C., 24 hours, 2.3 MPa saturated condition).

(3) Characteristic evaluation item of zeolite-containing hardened body The zeolite-containing hardened body produced as described above was subjected to compressive strength measurement, bending strength measurement, synthetic mineral phase identification, and pore size distribution measurement, and its characteristics were evaluated.

  The compressive strength measurement was performed on the produced zeolite-containing cured body (4 × 4 × 16 cm) according to the mortar test method described in JIS R 5201.

  The bending strength was measured in accordance with the mortar test method shown in JIS R 5201 for the produced zeolite-containing cured product (4 × 4 × 16 cm).

  The identification of the synthetic mineral phase was performed by powder X-ray diffraction (XRD), and the main mineral species constituting the zeolite-containing hardened body were identified based on the identification result.

  The pore size distribution was measured with a mercury intrusion pore size distribution measuring device.

(4) Experimental results (4-1) Effect of sodium hydroxide compounding amount In order to clarify the effect of sodium hydroxide compounding amount on the properties of the zeolite-containing cured product, the sodium hydroxide compounding amount is different in Table 1. Zeolite-containing cured bodies were produced under the conditions of Formulation 1 to Formulation 6, and the characteristics of these zeolite-containing cured bodies were compared and examined. The results are shown in Table 3. The unit of compressive strength and bending strength in Table 3 is N / mm ² .

As shown in Table 3, it became clear that a zeolite-containing cured product having good compressive strength and bending strength can be obtained under any blending conditions. In particular, when Formulation 3 is applied, the compressive strength is 63.7 N / mm ² and the bending strength is 8.8 N / mm ² , and a zeolite-containing cured body having extremely good compressive strength and bending strength can be manufactured. Became clear. Moreover, the tendency which the compressive strength declines gradually was shown, so that the amount of sodium hydroxide addition was increased and it was decreased with the mixing | blending 3 as a boundary.

  Next, the result of having analyzed the main component mineral contained in a zeolite containing hardening body by XRD is shown in FIG. When the NaOH addition rate was 7.8% or more, formation of zeolitic minerals gmelinite-Na and calcite (Analcime-C) was confirmed. Moreover, it became clear that the production amounts of gmelinite-Na and calcite (Analcime-C) increase as the NaOH addition rate increases. Furthermore, in all cases of Formulations 1 to 6, formation of zeolite P1, which is a zeolitic mineral, was confirmed. Moreover, it became clear that the production amount of zeolite P1 increases particularly when the NaOH addition rate is 4.7 to 9.4%.

  Moreover, when the experimental results on compressive strength and bending strength shown in Table 3 and the identification results of the zeolitic mineral species shown in FIG. 1 are comprehensively judged, gmelinite-Na, calcite (Analcime-C) It was revealed that the most excellent compressive strength and flexural strength can be obtained when the NaOH addition rate is 9.4%, which contains a large amount of the three types of zeolite minerals Z) and zeolite P1.

  From the above results, when sodium hydroxide is used as the alkali hydroxide, in order to contain gmelinite-Na and calcite (Analcime-C), the alkali hydroxide addition rate to the granular material is 7.8% or more is preferable, and it has been found that the content can be increased as the alkali hydroxide addition ratio is increased in this range. Moreover, about the zeolite P1, it turned out that the content can be increased especially by setting the alkali hydroxide addition rate to 9.4% or less, preferably 4.7 to 9.4%. The compressive strength and flexural strength tend to increase as the zeolite content increases. Alkali hydroxide addition rate in the range where gmelinite-Na, calcite (Analcime-C), and zeolite P1 coexist. In particular, it has become clear that this can be enhanced.

(4-2) Effect of potassium hydroxide content In order to clarify the effect of the amount of potassium hydroxide on the properties of the zeolite-containing cured body, the content of potassium hydroxide is different from Formulation 7 to Formulation 13 in Table 2. The zeolite-containing cured bodies were produced under the conditions described above, and the characteristics of these zeolite-containing cured bodies were compared and examined. The results are shown in Table 4. The unit of compressive strength and bending strength in Table 4 is N / mm ² .

As shown in Table 4, it became clear that a zeolite-containing cured body having good compressive strength and bending strength can be obtained under any blending conditions. In particular, when Formulation 10 is applied, the compressive strength is 56.1 N / mm ² and the flexural strength is 10.2 N / mm ² , and a zeolite-containing cured body having extremely good compressive strength and flexural strength can be manufactured. Became clear.

  Next, the result of having analyzed the main constituent mineral contained in a zeolite containing hardening body by XRD is shown in FIG. When the KOH addition rate was 6.6% or more, the formation of zeolitic minerals Merlinoite and philipsite-K was confirmed. Moreover, it became clear that the production amount of merlinolite (Merlinoite) and philipite (philipsite-K) increases as the KOH addition rate increases. Furthermore, when the KOH addition rate is 8.8% or less, the formation of the zeolite mineral chabazite-Ca is confirmed, and when the KOH addition rate is 6.6%, the chabazite-Ca is generated. ) Was found to increase the most.

  In addition, when the results shown in Table 4 and the experimental results shown in FIG. 2 are comprehensively judged, the most excellent compression is achieved at a KOH addition rate of 11.0% which is a boundary region where chabazite-Ca is not generated. It was found that strength and bending strength can be obtained.

  From the above results, when potassium hydroxide is used as the alkali hydroxide, in order to contain merlinite and philipsite-K, the alkali hydroxide addition ratio to the granular material is 6.6. It was found that the content can be increased as the alkali hydroxide addition ratio is increased in this range. In order to contain chabazite-Ca, the alkali hydroxide addition rate is preferably 8.8% or less, more preferably 4.4% to 8.8%, more preferably 6 It was found that the content of chabazite-Ca can be increased most by setting the content to 6%. Compressive strength and flexural strength tend to increase as the zeolite content increases, and water in the range where merlinite (Merlinoite) and phillipsite (K) and chabazite-Ca coexist. It has been clarified that the alkali oxide addition rate can be particularly increased by setting the alkali oxide addition rate.

(4-3) Influence of blended alkali species In order to clarify the effect of blended alkali species on the properties of the zeolite-containing cured body, a zeolite-containing cured body was produced under the conditions of blending 1 and blending 7 with different alkali species. The pore size distribution of these zeolite-containing cured bodies was compared and examined. The results are shown in FIG. Table 5 shows the results of comparing the pore characteristics of Formulation 1 and Formulation 7.

  As shown in FIG. 3, when the alkali hydroxide is potassium hydroxide, the total pore volume ratio increases, but the maximum frequency diameter decreases. It is considered that the smaller the maximum frequency diameter is, the more advantageous the strength characteristics are. Therefore, it has been found that it is superior to the case where the alkali hydroxide is sodium hydroxide.

(4-4) Effect of presence or absence of physical restraint pressure In order to clarify the influence of the presence or absence of physical restraint pressure in the second step on the properties of the zeolite-containing cured body, two kneaded materials were prepared under the conditions of Formulation 7. On the other hand, the second step was carried out under the same conditions as in (2) above, and the other was carried out while applying a physical restraint pressure. The kneaded material that had been allowed to stand for 2 weeks was placed in a steam autoclave and hydrothermally treated under general curing conditions (220 ° C., 24 hours, 2.3 MPa saturated condition). In this experiment, fly ash having a lot different from that in (2) was used.

  The physical restraint pressure was applied as follows. The kneaded material was accommodated in the mold 2 of the restraint pressure applying apparatus 1 shown in FIG. 4 (inner dimensions: 20 cm × 20 cm cross section, height 35 cm). A PEEK release plate (not shown) was installed on the inner surface of the mold 2 in order to facilitate removal of the zeolite-containing cured body after completion of steam curing. Moreover, the height of the kneaded material accommodated was 15 cm. After the kneaded material is stored in the mold 2, the mold 2 on which the inner lid 3 is placed is placed on a vibration table (TV series manufactured by EXEN), and vibrations with a frequency of 2500 Hz and an amplitude of 1.5 mm are kneaded. The material was defoamed and compacted for 4 minutes. Next, the upper lid 5 was fixed to the frame mold 2 by screwing. Then, the displacement of the spring 4 accommodated in the inner lid 3 from the equilibrium position (the difference in length of the spring 4 before and after the upper lid 5 is screwed), the spring constant of the spring 4 itself, and the bottom area of the inner lid 3 From this, the magnitude of the physical restraining pressure applied to the kneaded material was calculated to be 0.13 MPa. Then, the kneaded material was allowed to stand for 2 weeks in a state where a restraining pressure was applied. The material of the mold 2, the inner lid 3 and the upper lid 5 was stainless steel. The compressive strength measurement was performed according to JIS R 5201 using a test body obtained by cutting the produced zeolite-containing cured body into a cylindrical shape having a diameter of 35 mm and a height of 70 mm.

Results of compressive strength of the resulting zeolite-containing cured product was measured, whereas when not impart physical restraint pressure was 81N / mm ^2, when provided with physical confining pressure is 92N / mm ² Thus, it was clarified that the strength can be increased by applying a physical restraining pressure. As a result of XRD analysis, there was no difference in the type of generated mineral depending on the presence or absence of physical restraint pressure.

Here, as shown in Table 4, in the experiment of (4-2) above, the compression strength when the kneaded material was produced under the condition of Formulation 7 was 48.2 N / mm ² , In this experiment, it was 81 N / mm ² and the compressive strength was greatly improved. Since the experimental condition (4-2) and the experimental condition were all the same except for the difference in the fly ash lot, there was a possibility that some parameters of fly ash affected the magnitude of the compressive strength. Was suggested. Therefore, as a result of examining the difference in the fly ash lot, the fly ash used in this experiment has a higher degree of fineness than the fly ash used in (4-2) above (the fly ash used in this experiment). (The average particle size was 12 μm, whereas the average particle size of the fly ash used in (4-2) above was 16 μm). From the qualitative evaluation results, it was confirmed that the amorphous amount was large. . In addition, although the difference was not seen in the produced | generated mineral seed | species, the amount of zeolite production was less with the zeolite containing hardening body obtained by this experiment.

  From these results, the factors that improve the compressive strength of the zeolite-containing cured body were considered as follows. In other words, when fly ash having a high degree of fineness, a large amount of amorphous material, and a high reactivity is used, a large amount of amorphous phase is formed in the zeolite-containing cured body before the zeolite is formed, As a result, the amount of the amorphous phase is increased, and the amorphous phase plays a role like an adhesive in the zeolite-containing cured body. As a result, it is considered that the compressive strength is increased.

  The zeolite-containing cured product obtained by the production method of the present invention can be used as a substitute material for a concrete member that is desired to be used stably for a very long period of time, and as a block material such as brick. Moreover, since zeolite has a deodorizing, moisture absorption, humidity control, and moisture releasing function, it can also be used as a building material having these functions. As a specific example, it can be used as a building material having a function of adsorbing organic molecules that cause sick house syndrome. Further, it can be used as a solid adsorbent, an ion exchange material, a catalyst, and the like. It can also be used as an adsorbent for carbon dioxide, which is a greenhouse gas.

Claims (4)

A first step of kneading an amorphous material-containing granular material containing silica and alumina, an alkali hydroxide, and water to obtain a solid kneaded lump of kneaded material without performing dehydration press treatment, and the kneaded material a second step and, seen including a third step of contacting the water vapor directly into the mixing materials that are hardened, the sodium alkali hydroxide hydroxide to harden by the standing water and the kneaded material while maintaining the shape Or the manufacturing method of the zeolite containing hardening body characterized by being potassium hydroxide . The method for producing a zeolite-containing cured body according to claim 1, wherein the second step is performed while a physical restraining pressure is applied to the kneaded material. The method for producing a zeolite-containing cured body according to claim 1 or 2 , wherein the third step is a hydrothermal treatment under saturated vapor pressure. The method for producing a zeolite-containing cured body according to any one of claims 1 to 3, wherein fly ash is used as the powder of amorphous material containing silica and alumina.