JP4535823B2 - Production method of granular slaked lime - Google Patents

Description

The present invention is a granular material suitable for soil conditioners, acid rain neutralizers, wire drawing materials, livestock excreta and virus and bacteria disinfectants, bottom sediment improvers such as sea bottom and lake bottom, etc. it relates to the slaked lime of production how.

  Quicklime and slaked lime are used for agricultural soil modification, livestock excreta, and virus and bacterial disinfection. Further, slaked lime is generally used as a line drawing material for displaying a competition track or the like on a ground such as a school. Quicklime is in danger of generating high temperatures due to contact with water and moisture in the air during storage and spraying. Slaked lime is synthesized by bringing quick lime and water into contact with each other to cause a digestion reaction. For this reason, it does not generate heat like quicklime even when stored in the air, but slaked lime is difficult to handle because it is obtained in the form of fine powder and is scattered by the wind during and after application to the soil. As a result, the spraying effect was reduced and there was a problem of harming human livestock. Similarly, when slaked lime powder is put into a line drawing device, the slaked lime powder is scattered by the wind during drawing and adheres to the operator's body, or the edges of the drawn line are lightly blurred. Therefore, various attempts have been made to improve the working environment by granulating slaked lime. Usually, this granular slaked lime is produced only in a small amount at the time of the production of slaked lime, specifically only 30% or less, and most of the remainder was obtained in the form of fine powder, so that stable production It was difficult.

As a measure to solve this problem, a granulating agent containing organic matter such as stefen wastewater concentrate, alcohol fermentation waste concentrate, lignin sulfonate solution and the like is added to slaked lime and kneaded under a pressure of 25 to 70 kg / cm ^2. A kneading step, an extrusion granulation step in which the kneaded slaked lime is passed through a screen having a thickness of 3 mm or less at a pressure of 5 to 40 kg / cm ² , and a drying step in which the extruded granulated slaked lime is statically dried. A method for producing granular slaked lime, which is characterized by being sequentially processed, is disclosed (for example, see Patent Document 1). By the manufacturing method shown in Patent Document 1, a space is formed by drying the moisture of the granulating agent in the internal structure, facilitating moisture absorption and facilitating disintegration.
Moreover, after kneading slaked lime powder with an aqueous methyl alcohol solution, a method for producing slaked lime is disclosed in which the kneaded product is pressed against a perforated plate and small pieces discharged from each hole are dried to obtain granulated slaked lime. (For example, refer to Patent Document 2). According to the manufacturing method shown in Patent Document 2, in order to obtain slaked lime with less scattering and excellent fluidity, it can be formed into granules or granules and can be easily produced and produced in large quantities. .

In addition, when synthesizing slaked lime by reaction of quicklime and water, slaked lime is granulated by granulating means using the coexisting moisture as a binder, and high-strength grains are produced using the chemical reaction that occurs at that time The manufacturing method of the granular slaked lime characterized by doing is disclosed (for example, refer patent document 3). In Patent Document 3, granular slaked lime having a high strength can be obtained by an economical and simplified method.
Furthermore, by spraying a slurry prepared by adding water to slaked lime in a spray drying chamber in which quick lime powder was allowed to flow, the sprayed water-containing slaked lime particles collide with quick lime, and by hydration reaction, There is disclosed a method for producing granular slaked lime, which generates heat at the same time as dehydration, removes moisture in slaked lime grains, and dries (see, for example, Patent Document 4). By the production method shown in Patent Document 4, the particle size is relatively uniform, the water content in the granules is small, the water disintegration is excellent, the drying cost can be reduced, the quality is excellent, and the production cost is low. Granular slaked lime can be obtained.
Japanese Patent Publication No. 63-8047 Japanese Patent Publication No. 63-16332 Japanese Unexamined Patent Publication No. 63-123812 JP-A 63-297251

However, the granular slaked lime shown in Patent Documents 1 to 4 is obtained by a method such as granulating and drying by adding water or additives to powdered slaked lime, so that it is a secondary product. The production efficiency was extremely poor.
On the other hand, the bottom of closed sea areas such as bays, fish farms, lakes, dam lakes, canals, moats, etc. have little water flow, accumulation of residual food, fish excrement, and human wastewater. Organic matter is likely to accumulate due to the inflow of water, and when the natural purification capacity is exceeded, the organic matter deposited on the bottom oxidizes and decomposes to produce organic acids such as lactic acid, propionic acid and acetic acid, and anaerobic bacteria grow. As sulfur oxides are reduced, toxic hydrogen sulfide will surface and cause damage. As a method for preventing this, a method is known in which a lime-based alkaline substance is added to form an alkaline film on the bottom surface, and the activity of anaerobic bacteria is lowered to suppress the generation of hydrogen sulfide. Has been implemented for many years. However, when powdered slaked lime is sprayed on the sea or lake, it is easily washed away by waves, so a large amount of slaked lime must be sprayed in order to reach the intended sea or lake bottom. There was a problem that had to be done. In addition, when quick lime is sprayed on the sea or lake, a heat-generating digestive reaction occurs rapidly, and the water temperature and pH of the sprayed portion rapidly increase, contributing to deterioration of the environment.

Quicklime and slaked lime are used to sterilize barns in livestock such as chickens, pigs, and cattle. However, there was a problem that scattered as dust. In addition, when slaked lime is used, there has been a problem that livestock and workers sucked floating dust generated when opening a bag enclosing slaked lime or during work.
Also, when disposing of livestock due to the occurrence of bird flu, disinfection work was carried out by spraying slaked lime, but since slaked lime is easily wound up in the wind, workability is poor, and slaked lime wound up in this wind However, there was a problem that it accumulated as falling dust in the houses around the disinfection work.
Furthermore, slaked lime is sprayed as a measure to improve soil and acid rain. Conventionally, when slaked lime is sprayed, it is difficult to spray slaked lime evenly when the wind blows, and it accumulates as falling dust in the surrounding houses. There was a problem. Moreover, in the forest where slaked lime is sprayed, slaked lime accumulates on the skin of the leaves of the trees, which not only makes the landscape white, but also has an adverse effect on vegetation.

The object of the present invention is suitable for soil conditioners used for agricultural soil reforming, acid rain neutralizers, line drawing materials, livestock excreta and virus and bacteria disinfectants, bottom sediment improving agents such as seabed and lake bottom, etc. It is to provide a manufacturing how such particulate slaked lime.

Invention, pressurized particle size 0.5Mm～11.2Mm, a coarse quicklime apparent specific gravity is adjusted to 0.8 to 1.3 in the range of 0.12MPa~0.6MPa according to claim 1 It is the manufacturing method of the granular slaked lime characterized by making it contact with water vapor | steam in the performed atmosphere, and digesting partially within the range of 20%-85%.
In the invention which concerns on Claim 1, according to the said manufacturing method, partial digestion is carried out from coarse-grain quicklime to granular slaked lime, without an apparent change. Specifically, in the conventional method for producing granular slaked lime, in the process of total digestion of coarse slaked lime and powdered slaked lime, only natural slaked lime that has been naturally sized to a predetermined particle size using a sieve is used. Granular slaked lime was obtained by subjecting the powdered slaked lime obtained by total digestion of quick lime to granulation and the like. While maintaining the particle size of the coarse quicklime by bringing into partial digestion in contact with, first, digest the decalcified pores, pores, etc. formed in the course of the coarse quicklime surface, the coarse quicklime, Subsequently, granular slaked lime is obtained by digesting the vicinity of the periphery. Partial digestion is performed so that the digestibility is within a range of 20% to 85% by bringing coarse quicklime into contact with water vapor. Generation of slaked lime powder does not occur in the partial digestion reaction in which coarse lime is brought into contact with water vapor. That is, even if it does not give a granulation process etc., it has a desired particle size and the surface vicinity has the granular slaked lime of the slaked lime area | region. In addition, with this production method, water hydration can be controlled to some extent. The granular slaked lime obtained by the production method of the present invention has a structure in which the raw coarse lime as a raw material is not digested but partially digested, and the quick lime region and the slaked lime region are distributed at a predetermined ratio. I'm taking it.

Invention, pressurized particle size 0.5Mm～11.2Mm, a coarse quicklime apparent specific gravity is adjusted to 0.8 to 1.3 in the range of 0.12MPa~0.6MPa according to claim 2 It is the manufacturing method of the granular slaked lime characterized by making it contact with the mixed vapor | steam which each contains alcohol vapor | steam and water vapor | steam in the performed atmosphere, and digesting partially within the range of 20%-85%.
In the invention which concerns on Claim 2, according to the said manufacturing method, partial digestion is carried out from coarse-grain quicklime to granular slaked lime, without an apparent change. That is, the coarse quicklime is first formed on the coarse quicklime surface or in the baking process of the quicklime while maintaining the particle size of the coarse quicklime by partially digesting it by bringing it into contact with the mixed steam containing alcohol vapor and water vapor. The decarboxylated pores, pores, etc., are digested, and then the vicinity of the periphery is digested. Partial digestion is performed so that the digestibility is in the range of 20% to 85% by bringing coarse-grained quicklime into contact with mixed steam containing alcohol vapor and water vapor. Generation of slaked lime powder does not occur in the partial digestion reaction in which coarse-grained quicklime is brought into contact with mixed steam containing alcohol vapor and water vapor, respectively. In addition, with this production method, water hydration can be controlled to some extent.

In addition, it is possible to produce granular slaked lime in a short time compared to production under atmospheric pressure by pressurizing within the range of 0.12 MPa to 0.6 MPa ( 1.2 atm to 6 atm), Products that easily control the reactivity with water can be manufactured. In addition, it is particularly effective for quick lime having a large particle size because it uniformly digests the surface of quick lime, decarbonation pores, pores and the like.

The invention according to claim 3 is the method according to claim 2 , wherein the alcohol is one or more lower alcohols selected from the group consisting of methyl alcohol, ethyl alcohol and propyl alcohol. .

As shown in FIG. 1, the particle-like hydrated lime that is obtained by the method according to claim 1 to 3, the particle size of the particulate slaked lime 0.5Mm～11.2Mm, apparent specific gravity 0.7 to 1.3 And the digestibility is 20% to 85%, and it is possible to obtain a desired particle size without performing a process such as granulation , so that the production efficiency is high. Unlike quick lime, the granular slaked lime of the present invention hardly generates heat even when in contact with water, so that it can be handled safely and does not generate dust due to heat. Since the particle size or is larger granular and 0.5Mm～11.2Mm, never particulate slaked lime according to the invention are dust even when or working time of bag opening a bag which is sealed. Further, when the disposal and disinfection of livestock due to the occurrence of such avian influenza, when a particulate slaked lime present invention, since the particle size is larger granular and 0.5Mm～11.2Mm, be rolled up wind The working environment is greatly improved. Also, when using a particulate slaked lime present invention for soil amendment or acid rain measures, since the particle size is large granular with 0.5Mm～11.2Mm, performs a uniform sprayed from the air without scattering due to wind It becomes possible. Also, unlike powdered slaked lime, the forest sprayed with the granular slaked lime of the present invention is not environmentally friendly because it does not accumulate excessively on the skin of tree leaves. Furthermore, since the apparent specific gravity of the granular slaked lime of the present invention is increased to 0.7 to 1.3 as compared with conventional slaked lime and granular slaked lime, an equivalent amount of alkali can be supplied with a small volume. There is also an advantage that the amount of spraying per unit area can be reduced. In particular, in the case of spraying from the air, such as soil improvement and acid rain countermeasures, and improving the bottom of the sea and lake bottoms, it is possible to spread a wide range with the same loading tank quantity such as airplanes, helicopters, agricultural machines, ships, etc. Also excellent. Moreover, since the granular slaked lime of the present invention has a particle size of 0.5 mm to 11.2 mm when sprayed on the sea bottom or lake bottom as a bottom sediment improving agent, it reaches the target location without being swept away by waves or the like. In addition, since the vicinity of the surface is a slaked lime region and the inside is a quick lime region, a rapid digestion reaction does not occur. Furthermore, it does not disintegrate moderately with respect to water and remains as a lump, so it is environmentally friendly. Thus, having the above properties, soil modifiers used for agricultural soil modification, acid rain neutralizers, wire drawing materials, livestock excreta and virus and bacteria disinfectants, seabed and lake bottom sediment improvement It becomes a material suitable for an agent or the like.

As described above, the production method of the particulate slaked lime of the present invention, particle size 0.5Mm～11.2Mm, a coarse quicklime apparent specific gravity is adjusted to 0.8 to 1.3 0.12MPa～0 Digestion by contacting with water vapor in an atmosphere pressurized within a range of 0.6 MPa , or contacting with mixed vapor containing alcohol vapor and water vapor in an atmosphere pressurized within a range of 0.12 MPa to 0.6 MPa. Particulate digestion within a range of 20% to 85% yields granular slaked lime. By this manufacturing method, it is possible to partially digest coarse coarse lime into granular slaked lime without any apparent change. In addition, it is possible to produce granular slaked lime in a short time compared to the production under atmospheric pressure by pressurizing the partial digestion atmosphere within the above range, and the production of products that can easily control the reactivity with water It becomes possible. In addition, it is particularly effective for quick lime having a large particle size because it uniformly digests the surface of quick lime, decarbonation pores, pores and the like.

Particulate slaked lime obtained by the method of or the invention, the granular particle size of the hydrated lime 0.5Mm～11.2Mm, the apparent specific gravity 0.7 to 1.3, and digestibility of 20% to 85% It is characterized by that. The production efficiency is high because a desired particle size can be obtained without performing a process such as granulation. Unlike quick lime, the granular slaked lime of the present invention hardly generates heat even when in contact with water, so that it can be handled safely and does not generate dust due to heat. Since the particle size or is larger granular and 0.5Mm～11.2Mm, never particulate slaked lime according to the invention are dust even when or working time of bag opening a bag which is sealed. Further, when the disposal and disinfection of livestock due to the occurrence of such avian influenza, when a particulate slaked lime present invention, since the particle size is larger granular and 0.5Mm～11.2Mm, be rolled up wind The working environment is greatly improved. Also, when using a particulate slaked lime present invention for soil amendment or acid rain measures, since the particle size is large granular with 0.5Mm～11.2Mm, performs a uniform sprayed from the air without scattering due to wind It becomes possible. Also, unlike powdered slaked lime, the forest sprayed with the granular slaked lime of the present invention is not environmentally friendly because it does not accumulate excessively on the skin of tree leaves. Furthermore, since the apparent specific gravity of the granular slaked lime of the present invention is increased to 0.7 to 1.3 as compared with conventional slaked lime and granular slaked lime, an equivalent amount of alkali can be supplied with a small volume. There is also an advantage that the amount of spraying per unit area can be reduced. In particular, in the case of spraying from the air, such as soil improvement and acid rain countermeasures, and improving the bottom of the sea and lake bottoms, it is possible to spread a wide range with the same loading tank quantity such as airplanes, helicopters, agricultural machines, ships, etc. Also excellent. Moreover, since the granular slaked lime of the present invention has a particle size of 0.5 mm to 11.2 mm when sprayed on the sea bottom or lake bottom as a bottom sediment improving agent, it reaches the target location without being swept away by waves or the like. It is also possible that the raw coarse lime as a raw material is not digested but partially digested, the surface vicinity is a slaked lime region, the inside is a quick lime region, and takes a configuration distributed at a predetermined ratio, Does not cause a rapid digestive reaction. Furthermore, it is environmentally friendly because it does not disintegrate moderately to water and remains in a lump. Thus, the granular slaked lime having the above physical properties is a soil modifier, an acid rain neutralizer, a line drawing material, livestock excreta and virus and bacteria disinfectant used for agricultural soil reforming, bottoms such as sea bottom and lake bottom. It becomes a material suitable for a quality improving agent and the like.

The 1st manufacturing method of the granular slaked lime of this invention is demonstrated.
As shown to Fig.1 (a), the quicklime 11 which is the raw material of the granular slaked lime of this invention is obtained by baking a limestone and removing the carbonic acid component in a limestone like the normal manufacturing method of quicklime. In this manufacturing process, quick lime powders aggregate to form pores that are gaps formed between the aggregated particles, and decarbonation holes 11a that are generated by the removal of carbonic acid components. Resulting quicklime, crushed to a certain size, by controlling the particle size at sieve or the like, suitable particle size as a raw material of the particulate slaked lime present invention 0.5Mm～11.2Mm, apparent specific gravity 0 Adjusted to coarse lime of 8 to 1.3 . Particle size 1 mm to 5 mm, apparent specific gravity preferably 0.9 to 1.1.
The characteristic structure of the manufacturing method of the granular slaked lime of this invention exists in the place which makes this coarse grain quick lime contact water vapor | steam, and digestes partially within the range of 20%-85%. The temperature of the water vapor is preferably in the range of 70 ° C to 100 ° C at atmospheric pressure. If the steam is less than 70 ° C, the exothermic energy generated from quicklime and water due to the latent heat is lost to the temperature rise of the steam, so it becomes a liquid phase reaction temporarily and easily causes pulverization. Because.

  The digestibility in the present invention refers to a ratio obtained by dividing the weight increase of slaked lime before and after partial digestion by the theoretical amount of digested water with respect to the weight of slaked lime before partial digestion. When the obtained granular slaked lime is used as a soil conditioner used for agricultural soil modification, the particle size is 0.5 to 4 mm and the digestibility is 40% to 85%. When used as a drawn wire, the particle size is 0.5 to 1 mm. The digestion rate is 60% to 80%, the digestion rate is 20 to 60% with a particle size of 2 to 4 mm when used for livestock excrement and virus or bacteria disinfectant, and the particle size of 0. The digestibility is 5% to 2mm and the digestibility is 60% to 85%. When used as a bottom sediment improving agent such as the seabed or lake bottom, the digestibility is 40% to 85% with a particle size of 0.5 to 11.2mm. It is preferable to appropriately adjust the production conditions. By changing this manufacturing condition, the hydration property to water can be controlled to some extent freely. The digestion rate is partially digested within the range of 20% to 85% under the above production conditions. If the digestibility is less than 20%, the rate of digestion film in the decarbonation pores and pores is low, and the property of quicklime is strong, so there is a risk of generating high temperature by absorbing moisture and moisture. If the digestibility exceeds 85%, the generation rate of powdered slaked lime increases, so that a sufficient effect as granular slaked lime cannot be obtained, and the yield also deteriorates. The digestibility is preferably 25% to 70%.

  As shown in FIG. 1 (b), by contacting the coarse quicklime with water vapor and partially digesting it into granular slaked lime, while maintaining the particle size of the coarse quicklime, first, the coarse quicklime surface and coarse granules Decarboxylation pores, pores, etc. formed in the production process of quicklime are digested, and then the vicinity of the periphery is digested. In addition, the broken line shown in FIG.1 (b) shows the surface position of coarse grain quicklime. Reference numeral 11b in FIG. 1 (b) indicates the position where the decarbonation holes and pores were formed. Partial digestion is performed so that the digestibility is within a range of 20% to 85% by bringing coarse quicklime into contact with water vapor. In the partial digestion reaction in which the coarse lime is brought into contact with water vapor, slaked lime powder is hardly generated. As shown in FIG. 1B, the granular slaked lime obtained by the production method of the present invention is partially digested instead of digesting the raw coarse lime as a raw material. The region 13 and the region 13 are distributed at a predetermined rate. The granular slaked lime obtained by the first production method of the present invention is a slaked lime in which the granular slaked lime is obtained while maintaining the particle size of the raw coarse lime, and the apparent specific gravity, which is the ratio of volume to weight, is obtained by a normal production method. About 2 to 3 times, and approximately the same as the apparent specific gravity of the raw coarse lime. For this reason, compared with conventional slaked lime and granular slaked lime, since the apparent specific gravity is increased to 0.7 to 1.3, an equivalent amount of alkali can be supplied with a small volume. There is also an advantage that the amount of application is small. In particular, when used for soil modifiers, acid rain neutralizers, disinfection, etc., the amount of spraying per unit area is small, and when transporting in the same loading tank, a substantial amount of alkali is transported. Cost reduction can be expected.

Next, the 2nd manufacturing method of the granular slaked lime of this invention is demonstrated.
In the second production method, the coarse-grained quick lime that is the raw material of the first production method is brought into contact with a mixed vapor containing alcohol vapor and water vapor, respectively, so that the digestibility is partially digested within a range of 20% to 85%. Features. The ratio of the mixed steam containing alcohol vapor and water vapor (alcohol vapor / water vapor) is supplied at a ratio of 1/100 to 15/100. If it is less than 1/100, that is, if the proportion of alcohol vapor is low, the effectiveness of alcohol vapor addition is not recognized, and if it exceeds 15/100, that is, if the proportion of alcohol vapor is high, not only handling becomes difficult, but also the cost increases. It becomes. A ratio of 3/100 to 10/100 is more preferable. The effect of shortening the production time can be expected by bringing coarse quicklime into contact with mixed steam containing alcohol vapor and water vapor, respectively. The temperature of the mixed vapor containing alcohol vapor and water vapor is preferably in the range of 70 ° C. to 100 ° C. at atmospheric pressure.

  In the first manufacturing method and the second manufacturing method, it is preferable to pressurize the partially digesting atmosphere within a range of 0.1 MPa to 0.6 MPa (1 atm to 6 atm). By applying pressure, granular slaked lime having a larger apparent specific gravity than that of the production method under atmospheric pressure can be obtained, and a significant reduction in production time can be expected. The reason why the pressurizing condition is defined within the above range is that if the upper limit value is exceeded, the pressure resistance of the manufacturing apparatus must be increased more than necessary, which increases the cost. Moreover, since manufacture in an extremely short time is possible, it becomes difficult to control the digestibility of granular slaked lime. The pressure condition is more preferably 0.12 MPa to 0.2 MPa (1.2 atm to 2 atm). In the case of partial digestion while applying pressure, since it is necessary to make the digesting atmosphere a sealed space, the continuous flow type is not suitable, and the batch type is preferable. Examples of the alcohol used in the second production method include one or more lower alcohols selected from the group consisting of methyl alcohol, ethyl alcohol, and propyl alcohol. The temperature of the water vapor in the first production method and the temperature of the mixed vapor containing alcohol vapor and water vapor in the second production method are such that the partially digested atmosphere is added within the range of 0.1 MPa to 0.6 MPa (1 atm to 6 atm). When pressurized, it is preferable to use water vapor at a higher temperature than atmospheric pressure, depending on the pressure range. The steam temperature when the partially digested atmosphere is pressurized to an upper limit of 0.6 MPa (6 atm) is preferably in the range of 160 to 180 ° C.

The granular slaked lime of the present invention is granular slaked lime obtained by the first and second production methods of the present invention, and its characteristic configuration is that the particle size of the granular slaked lime is 0.5 mm to 11.2 mm and the apparent specific gravity is 0. 0.7 to 1.3, and the digestibility is 20% to 85%. The production efficiency is high because a desired particle size can be obtained without performing a process such as granulation. Moreover, since the granular slaked lime of the present invention has a particle size of 0.5 mm to 11.2 mm when sprayed on the sea bottom or lake bottom as a bottom sediment improving agent, it reaches the target location without being swept away by waves or the like. Moreover, as shown in FIG.1 (b), not all the coarse-grain quicklime used as a raw material is digested, but is partially digested, the surface vicinity becomes the slaked lime area | region 13, and the inside becomes the quicklime area | region 12, and quicklime is obtained. Since the slaked lime film is formed on the decarbonation pores and pores while the decarbonation pores and pores are present, the composition is distributed at a predetermined ratio, so that a rapid digestion reaction does not occur. Furthermore, it is environmentally friendly because it does not disintegrate moderately to water and remains in a lump. Thus, the granular slaked lime having the above physical properties is a soil modifier, an acid rain neutralizer, a line drawing material, livestock excreta and virus and bacteria disinfectant used for agricultural soil reforming, bottoms such as sea bottom and lake bottom. It becomes a material suitable for a quality improving agent and the like.

Next, examples of the present invention will be described in detail together with comparative examples.
<Examples 1-3>
Particle size 0.5 mm to 2 mm, the coarse quicklime apparent specific gravity is adjusted to 1.02 under a pressure of 0.1 MPa (1 atm), moiety as digestibility in contact with water vapor of 20% digestion The granular slaked lime with an apparent specific gravity of 1.02 was produced (Example 1).
In addition, granular slaked lime having an apparent specific gravity of 0.96 and an apparent specific gravity of 0.88 was prepared in the same manner as in Example 1 except that the digestion rates were 40% and 80%, respectively (Example) 2 and 3).
<Examples 4 to 6>
Particle size 0.5 mm to 2 mm, the coarse quicklime apparent specific gravity is adjusted to 1.02 at a pressure of 0.2 MPa (2 atm), moiety as digestibility in contact with water vapor of 20% digestion To produce granular slaked lime having an apparent specific gravity of 1.02 (Example 4).
Further, granular slaked lime having an apparent specific gravity of 0.98 and an apparent specific gravity of 0.91 was prepared in the same manner as in Example 4 except that the digestion rates were 40% and 80%, respectively (Example) 5 and 6).
<Example 7>
Particle size 0.5 mm to 2 mm, the coarse quicklime apparent specific gravity is adjusted to 1.02 under a pressure of 0.6 MPa (6 atm), moiety as digestibility in contact with the water vapor is 40% digested The granular slaked lime with an apparent specific gravity of 1.00 was produced.

<Examples 8 to 10>
Particle size 2 mm to 4 mm, the coarse quicklime apparent specific gravity is adjusted to 0.97 under a pressure of 0.1 MPa (1 atm), performs partial digestion as digestibility in contact with the water vapor is 40% A granular slaked lime having an apparent specific gravity of 0.84 was prepared (Example 8).
Further, granular slaked lime having an apparent specific gravity of 0.88 and an apparent specific gravity of 0.91 in the same manner as in Example 8 except that the pressure of the partially digested atmosphere was changed to 0.2 MPa (2 atm) and 0.6 MPa (6 atm). Were prepared respectively (Examples 9 and 10).
<Examples 11 to 13>
Particle size 4Mm～11.2Mm, under the pressure of an apparent specific gravity of 0.1MPa the coarse quicklime adjusted to 0.84 (1 atm), the partial digestion so that 40% digestibility in contact with the water vapor This was done to produce granular slaked lime having an apparent specific gravity of 0.79 (Example 11).
Further, granular slaked lime having an apparent specific gravity of 0.81 and an apparent specific gravity of 0.82 in the same manner as in Example 11 except that the pressure of the partially digested atmosphere was changed to 0.2 MPa (2 atm) and 0.6 MPa (6 atm). Were produced respectively (Examples 12 and 13).
<Examples 14 and 15>
Particle size 0.5 mm to 2 mm, the coarse quicklime apparent specific gravity is adjusted to 1.02 under a pressure of 0.1 MPa (1 atm), it is brought into contact with a mixed vapor containing respectively 95% of steam and 5% ethanol vapor Thus, partial digestion was performed so that the digestibility was 40%, and granular slaked lime having an apparent specific gravity of 0.92 was produced (Example 14).
Further, granular slaked lime having an apparent specific gravity of 0.95 was prepared in the same manner as in Example 14 except that the pressure in the partially digested atmosphere was changed to 0.2 MPa (2 atm) (Example 15).
<Examples 16 and 17>
Particle size 2 mm to 4 mm, under a pressure of an apparent specific gravity of 0.97 to the adjusted coarse quicklime to 0.1 MPa (1 atm), in contact with the mixed vapor containing respectively 95% of steam and 5% ethanol vapor digestibility Partial digestion was performed to obtain 40% to produce granular slaked lime having an apparent specific gravity of 0.83 (Example 16).
Further, granular slaked lime having an apparent specific gravity of 0.87 was produced in the same manner as in Example 16 except that the pressure in the partially digested atmosphere was changed to 0.2 MPa (2 atm) (Example 17).
<Examples 18 and 19>
Particle size 4Mm～11.2Mm, under the pressure of an apparent specific gravity 0.84 to adjusted coarse quicklime to 0.1 MPa (1 atm), in contact with the mixed vapor containing respectively 95% of steam and 5% ethanol vapor Partial digestion was performed so that the digestibility was 40%, and granular slaked lime having an apparent specific gravity of 0.77 was produced (Example 18).
Further, granular slaked lime having an apparent specific gravity of 0.78 was produced in the same manner as in Example 18 except that the pressure in the partially digested atmosphere was changed to 0.2 MPa (2 atm) (Example 19).

<Examples 20 and 21>
Particle size 0.5 mm to 2 mm, under a pressure of an apparent specific gravity of 0.1MPa the coarse quicklime adjusted to 1.26 (1 atm), the partial digestion so that 40% digestibility in contact with the water vapor A granular slaked lime having an apparent specific gravity of 1.19 was prepared (Example 20).
Further, granular slaked lime having an apparent specific gravity of 1.23 was produced in the same manner as in Example 20 except that the pressure in the partially digested atmosphere was changed to 0.2 MPa (2 atm) (Example 21).
<Examples 22 and 23>
Particle size 2 mm to 4 mm, and under a pressure of an apparent specific gravity of 0.1MPa the coarse quicklime adjusted to 1.18 (1 atm), it is brought into contact with a mixed vapor containing respectively 95% of steam and 5% ethanol vapor digestion Partial digestion was performed so that the rate was 40%, and granular slaked lime having an apparent specific gravity of 1.06 was produced (Example 22).
Further, granular slaked lime having an apparent specific gravity of 1.10 was produced in the same manner as in Example 22 except that the pressure in the partially digested atmosphere was changed to 0.2 MPa (2 atm) (Example 23).
<Examples 24 and 25>
Particle size 4Mm～11.2Mm, a coarse quicklime apparent specific gravity is adjusted to 1.05 under a pressure of 0.1 MPa (1 atm), is brought into contact with a mixed vapor containing respectively 95% of steam and 5% ethanol vapor Thus, partial digestion was performed so that the digestibility was 40%, and granular slaked lime having an apparent specific gravity of 0.96 was produced (Example 24).
Further, granular slaked lime having an apparent specific gravity of 0.97 was prepared in the same manner as in Example 24 except that the pressure in the partially digested atmosphere was changed to 0.2 MPa (2 atm) (Example 25).

<Comparative Example 1>
Particle size 0.5Mm～4mm, apparent specific gravity 0.70 and digestibility were prepared adjusted granules slaked lime 100%.
<Comparative example 2>
A 50% by weight ethyl alcohol aqueous solution was kneaded at a rate of 300 g with respect to 600 g of slaked lime powder having a digestibility of 100%, and this kneaded product was extruded from a 3 mm circular hole and molded. The molded product was dried for 1 hour in a drier maintained at 105 ° C. The resulting dry product to adjust the particle size to 0.5~4mm obtain a granulated slaked lime.
<Comparative Example 3>
Water was kneaded at a rate of 120 g to 600 g of slaked lime powder having a digestibility of 100%, and a pressure of 45 kg / cm ² was applied to the kneaded product to form a plate-like slaked lime having a thickness of 3 mm. The plate-like slaked lime was dried for 1 hour 30 minutes in a drier maintained at 105 ° C. And crushing the dried plate slaked lime to yield a granulated slaked lime to adjust the particle size to 0.5 to 4 mm.

<Comparative Examples 4-6>
Particle size 0.5 mm to 2 mm, was prepared soft baking quick lime which is adjusted to an apparent specific gravity of 1.02 (Comparative Example 4).
The particle size of 2 mm to 4 mm, apparent specific gravity 0.97及beauty particle size 4Mm～11.2Mm, was prepared soft baking quicklime adjusted respectively to an apparent specific gravity 0.84 (Comparative Examples 5 and 6).

<Comparative Examples 7-9>
Particle size 0.5 mm to 2 mm, were prepared hard baked lime adjusted to an apparent specific gravity 1.26 (Comparative Example 7).
The particle size of 2 mm to 4 mm, apparent specific gravity 1.18及beauty particle size 4Mm～11.2Mm, was prepared hard baked lime adjusted respectively to an apparent specific gravity 1.05 (Comparative Examples 8 and 9).

<Comparison test 1>
Granular slaked lime obtained in Examples 1 to 25 and granular slaked lime of Comparative Example 1, granulated slaked lime of Comparative Examples 2 and 3, soft calcined quick lime of Comparative Examples 4 to 6, and hard calcined quick lime of Comparative Examples 7 to 9 The ignition loss and R-CO ₂ (rest CO ₂ ) were determined. In addition, the ignition loss (ignition loss) in this invention is the ratio reduced when a 1-g sample was heated at 1050 degreeC for 1 hour. As the main weight-reducing substance, calcium carbonate, bound water and adhering water contained in the sample can be considered. R—CO ₂ is the proportion of CO ₂ contained in the sample.

Moreover, about the granular slaked lime obtained in Examples 1-25, the granular slaked lime of Comparative Example 1, the granulated slaked lime of Comparative Examples 2 and 3, and the soft burned quicklime of Comparative Examples 4-9, the following activity tests and An underwater disintegration resistance test was conducted.
(1) Activity test Among the methods (coarse titration method) in which quick lime with a fixed particle size is put into warm water and neutralized with HCl and the consumption of HCl is measured, the activity 50 g method was used. Specifically, first, 50 g of quicklime sample was put into 2 liters of water maintained at a water temperature of 40 ° C. Subsequently, neutralization titration was performed using 4N HCl, and the amount of HCl consumed in 5 minutes was read. The larger the value, the greater the activity with water and the faster the reaction.

(2) Underwater disintegration resistance test First, after placing a predetermined amount of sample on a sieve having a sieve mesh of 0.5 m / m, the sieve was left still in water. Next, the sieve was allowed to stand in water for a predetermined time (1 hour and 24 hours), and after sieving the sample in water, the sieve was pulled up from the water. Next, the residue remaining on the sieve was dried at 105 ° C. for 1 hour, and its weight was measured. Subsequently, the residual rate was determined from the amount of sample placed on the sieve and the residual amount. It shows that the swelling collapse | disintegration in water is so small that this figure is large.

Table 1 shows the ignition loss of granular slaked lime of Examples 1 to 25, R-CO ₂ and evaluation test results. Granular slaked lime of Comparative Example 1, granulated slaked lime of Comparative Examples 2 and 3, softness of Comparative Examples 4 to 9 Table 2 shows the ignition loss of burnt lime, R-CO ₂ and evaluation test results.

As is apparent from Table 2, the granulated slaked lime of Comparative Example 1 that has been mainly used for improving the acidity of soil conventionally has an apparent specific gravity that is too small to be used as a bottom sediment improving agent for the seabed or lake bottom. There is a problem that it is easy to be swept away by waves and water currents and difficult to reach the intended bottom. Moreover, even if it reaches the target bottom, the specific gravity is lighter than sludge, so it is difficult to reform the inside of the bottom. Moreover, since the granular slaked lime of the comparative example 1 has high activity, when sprayed to rivers, oceans, lakes, etc., the water is alkalized before reaching the target bottom, and adversely affects the ecosystem that inhabits the water. There is a fear.
In addition, the granulated slaked lime of Comparative Example 2, like the granular slaked lime of Comparative Example 1, has an apparent specific gravity that is too small to be used as a bottom improving agent such as the seabed or lake bottom, and thus is easily washed away by waves and water currents. There is a problem that it is difficult to reach the bottom. Moreover, even if it reaches the target bottom, the specific gravity is lighter than sludge, so it is difficult to reform the inside of the bottom. In addition, the granulated slaked lime of Comparative Example 2 is not suitable for acid neutralization in soil reforming because of its low activity and too high resistance to disintegration in water after standing for 24 hours. Furthermore, since a large amount of ethyl alcohol is used as a drug and a drying process is required, there is a problem of high cost. Like the granulated slaked lime of Comparative Example 2, the granulated slaked lime of Comparative Example 3 is not suitable for acidic neutralization in soil reforming because of its low activity and too high resistance to disintegration in water after standing for 24 hours. Furthermore, since a drying process is required, there is a problem of high cost.
In addition, the soft calcined lime of Comparative Examples 4 to 6 has very high activity and low resistance to underwater collapse, so when sprayed on rivers, oceans, lakes, etc., the water is alkalized before reaching the target bottom. And may adversely affect the ecosystems that live in the water. Moreover, since it is quicklime, there exists a possibility of generating heat | fever with water and moisture, and it is not suitable for uses, such as soil improvement. Since the soft calcined lime of Comparative Examples 7 to 9 has low underwater collapse resistance, when sprayed on rivers, oceans, lakes, etc., ecosystems that inhabit the water by alkalizing the water before reaching the target bottom May be adversely affected. Moreover, since it is quicklime, there exists a possibility of generating heat | fever with water and moisture, and it is not suitable for uses, such as soil improvement.

  On the other hand, as apparent from Table 1, with the granular slaked lime of Examples 1 to 25, apparent specific gravity, activity, and resistance to disintegration in water are well balanced, and Examples 2 to 10, Examples 14 to 17, and Examples 20 to 23 are balanced. The granular slaked lime is particularly suitable for use as a soil modifier, and the granular slaked lime of Examples 3 and 6 is particularly suitable for use as a drawn wire. Examples 8 to 10, Examples 16 to 17 and Examples The granular slaked lime of Examples 22 to 23 is particularly suitable for the use as a stool disinfectant, and Examples 3 and 6 are particularly suitable for the use as an acid rain neutralizer. It turns out that the granular slaked lime of Examples 2-25 is especially suitable for the use of a bottom improvement agent.

  Specifically, in the granular slaked lime of Examples 1 to 3, when the digestibility increases, the loss on ignition of the granular slaked lime increases, and the apparent specific gravity tends to be smaller than the apparent specific gravity of the raw coarse lime. It was. In addition, the resistance to disintegration in water tended to increase as the digestibility increased. In addition, the activity was the smallest in Example 2 with a digestibility of 40%. In the granular slaked lime of Examples 4 to 7, there was a tendency that the apparent specific gravity was higher than those of Examples 1 to 3. Although not shown in Table 1, there was a tendency that the time required to reach a predetermined digestion rate was shortened by increasing the pressure of the partial digestion atmosphere.

Further, in the particulate slaked lime examples 8 to 13, is a coarse quicklime coarse quicklime as a raw material of not the magnitude particle size than the coarse particle quicklime as a raw material for Example 1-7, Example 1-7 Compared with, the apparent specific gravity decreased and the activity tended to decrease. In addition, the water disintegration resistance was slightly inferior to Examples 1-7.

  Moreover, in the granular slaked lime of Examples 14-19, although it was the granular slaked lime which carried out partial digestion by making coarse-granulated lime contact each with the mixed vapor | steam containing alcohol vapor | steam and water vapor | steam, the tendency for the apparent specific gravity of granular slaked lime to become small was seen. . Although not shown in Table 1, there was a tendency for the time to reach a predetermined digestibility to be shortened compared to contact with water vapor alone.

  In addition, the granular slaked lime of Examples 20 to 25 is a granular slaked lime made from hard-fired quicklime having a larger apparent specific gravity than the soft-fired quicklime having a smaller apparent specific gravity as the raw material in Examples 1 to 19, but the activity is small. As a result, the resistance to underwater collapse tended to increase.

The following tendency was seen from various condition changes in the process of producing granular slaked lime of Examples 1 to 25.
・ When digestibility is increased, (a1) loss on ignition increases and (a2) apparent specific gravity of granular slaked lime decreases. In addition, (a3) the degree of activity is the smallest at a digestibility of 40%, and thereafter the activity increases as the digestibility increases. (a4) Resistance to underwater collapse increases.
・ When the pressure in the partial digestion atmosphere is increased, the apparent specific gravity of (b1) granular slaked lime becomes larger than in the atmospheric digestion atmosphere. (b2) The activity is reduced. (b3) Digestion time can be shortened. (b4) Underwater collapse resistance increases.
-When the particle size of coarse quicklime is increased, the apparent specific gravity of (c1) coarse quicklime is reduced, so the apparent specific gravity of granular slaked lime is reduced. (c2) activity particle diameter 2mm~4mm decreases. (c3) Digestion time can be shortened. (c4) becomes the particle size 2mm~4mm is water disintegration resistance decreases.
・ In the case of partial digestion in contact with mixed steam containing alcohol vapor, the apparent specific gravity of (d1) granular slaked lime is smaller than that of water vapor alone. (d2) Increased activity. (d3) The digestion time can be shortened. (d4) Resistance to underwater collapse increases.

The granular slaked lime obtained by the production method of the present invention is a soil modifier, an acid rain neutralizer, a drawing wire, a livestock excrement and a virus or bacteria disinfectant used for agricultural soil modification, a bottom such as a seabed or a lake bottom. It can be applied to uses such as quality improvers.

(a) Sectional drawing of the coarse-grain quicklime used as the raw material of the granular slaked lime of this invention.

 (b) Sectional drawing of the granular slaked lime of this invention obtained by partially digesting the coarse-grain quicklime of Fig.1 (a).

10 Granulated slaked lime 11 Quick lime 11a Pore, decarbonation 12 Quick lime region 13 Slaked lime region

Claims (3)

And particle size 0.5Mm～11.2Mm, contacting the coarse quicklime apparent specific gravity is adjusted to 0.8 to 1.3 to the water vapor in the atmosphere was pressurized to within the range of 0.12MPa~0.6MPa A method for producing granular slaked lime, wherein the digestibility is partially digested within a range of 20% to 85%. Particle size 0.5Mm～11.2Mm, a coarse quicklime adjusted to an apparent specific gravity of 0.8 to 1.3 in an atmosphere pressurized to within the range of 0.12MPa~0.6MPa the alcohol vapor and water vapor A method for producing granular slaked lime, wherein the digestion rate is partially digested within a range of 20% to 85% by contacting with each of the mixed steams. The process according to claim 2, wherein the alcohol is one or more lower alcohols selected from the group consisting of methyl alcohol, ethyl alcohol and propyl alcohol.

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