JPS63283736A - Manufacture of globular granules of solidified chlorine agent - Google Patents

Abstract

PURPOSE:To eliminate pulverization in the manufacturing process and make the dissolving speed of granules faster, by extruding wet cake into column- shaped grains having described diameter, and then forming them in globular granules by a rolling granulator or a globular granule shaping machine. CONSTITUTION:After wet chlorine agent cakes are formed into column-shaped grains of 0.2-5mm diameter by extrusion, said column-shaped grains are granulated into globes of 0.2-5mm diameter by a rolling granulating machine or a globular granule shaping machine, and then dried to manufacture solidified globular granules of chlorine agent. As the chlorine agent, chlorinated isocyanuric acid compound such as trichloroisocyanuric acid, sodium dichloroisocyanurate or the like is suitable. A 0.5-0.9g/cm<3> bulk density of globular granulates of the chlorinated isocyanuric acid compound is suitable,.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing spherical granules of a solid chlorine agent having a low bulk density, a particle size of 0.2 to 5 mm, and a fast dissolution rate.

As solid chlorine agents, highly bleached powder, chlorinated isocyanuric acid compounds, etc. are used in various fields for sterilization, cleaning, or bleaching. It is also used as a disinfectant and disinfectant for tableware, cooking facilities, and utensils. Furthermore, it is also used to sterilize and bleach textiles.

(Prior Art) Solid chlorine agents come in the form of powders, granules, and even tablets, but powders are more commonly used in the form of granules or tablets than powders due to handling problems. Since this solid chlorine agent has low stability in a wet state, the slurry-like reaction product generated from the reaction system is usually dehydrated in the manufacturing process and immediately dried to form a wet cake to prevent the decomposition of the solid chlorine agent. Measures are being taken to suppress it.

Known examples of chlorinated isocyanuric acid compounds include trichloroisocyanuric acid, sodium dichloroisocyanurate anhydride or its hydrate, and potassium dichloroisocyanurate.

As a method for producing solid chlorine agent granules, the following method is known for chlorinated isocyanuric acid compounds, and is almost the same for highly bleached powder.

(1) A method of tabletting and pulverizing chlorinated incyanuric acid powder (Japanese Patent Publication No. 23198/1983).

(2) A method of compressing the powder using two rolls, forming it into a plate shape, and crushing it into granules (Japanese Patent Application Laid-Open No. 49-12538
No. 1, U.S. Pat. No. 3,985,744).

(3) After extruding and granulating the wet cake into somen shapes and fluidizing the extrusion granules, the dried product is formed into a plate shape using two rolls, crushed, and sieved to reduce bulk density. A method of making granules (Japanese Patent Application Laid-open No. 57576/1983).

(4) Furthermore, an anhydrous or hydrated alkali metal salt of dichloroisocyanuric acid, particularly a dihydrate of sodium dichloroisocyanurate, is obtained by spray granulation of an aqueous solution or slurry containing sodium dichloroisocyanurate (U.S. Pat. No. 4005087, No. 4182871), etc. have been proposed.

(Problems to be Solved by the Invention) The method of obtaining granules using the conventional method (1) described above is not economical, and powdered chlorinated isocyanuric acid adheres to the mold, resulting in binding, sticking, and caving. These problems tend to occur and are impractical. Method (2) is a dry granulation method, but the granules obtained by this method have a large bulk density and are hard, which tends to slow dissolution. (
In method 3), in order to improve the slow dissolution rate of the granules obtained by method (2), wet granulation is performed by extruding the wet cake into somen shapes before drying and powdering. After this extrusion granulation product is fluidized and dried, it is formed into a plate shape using two rolls (dry granulation), crushed, and sieved to produce granules with a low bulk density. The cylindrical granules that have been molded will collapse and turn into powder, and even if you adjust the extrusion pressure and screen diameter, or add a binder, they will turn into powder due to fluidized drying.
Furthermore, in order to prevent powdering during fluidized drying, even if you dry in place using a vacuum dryer or an electric dryer, the strength of somen-shaped or columnar molded products is extremely weak and the tendency to powder does not change.Normally, powder It takes a long time to dry in place, so fluidized drying is used for practical reasons. (4) is a method for obtaining anhydrous or hydrated alkali metal salts of dichloroisocyanuric acid, especially dihydrates of dichloroisocyanuric acid. Not only does it require a large amount of heat to evaporate water, but slurry is prone to problems such as clogging of the spray nozzle, wear and corrosion, and the material obtained by this method is semi-dry particles. They are a combination of comrades, that is, an aggregate of secondary particles, and the resulting granules tend to be easily powdered.

In order to solve the problems of the above-mentioned prior art, which are the problems of powdering in the method for producing granules of solid chlorine agent and the slow dissolution rate of the obtained solid chlorine agent,
As a result of evaluating the stability of solid chlorine agents in a wet state and examining various granulation methods, we found that after extrusion granulation of a wet cake, It has been found that when granulated into spherical granules, the spherical granules are strong, do not powder during granulation, drying, and transfer during use, and have a fast dissolution rate.

An object of the present invention is to provide a method for producing granules that eliminates powdering and has a high dissolution rate during the granulation process of solid chlorine agent into granules, the drying process, and the transfer of the granules.

(Means for Solving the Problems) The present invention provides a method for obtaining granules of a solid chlorine agent from a wet cake obtained in a manufacturing process of a solid chlorine agent, including: (a) extrusion granulation of a wet cake; Diameter 0.2
Granulate into a cylindrical shape with a diameter of ~5 mm, and (b) granulate the cylindrical granulated product into a spherical shape with a diameter of 0.2 to 5 mm using a rolling granulator or a spherical granulator, (c ) A method for producing spherical granules of a solid chlorine agent, characterized by comprising a drying step. The present invention will be further explained in detail below.

The solid chlorine agents used in the present invention include highly bleached powder and chlorinated isocyanuric acid compounds. The chlorinated isocyanuric acid compound is at least one compound selected from trichloroisocyanuric acid, sodium dichloroisocyanurate anhydride or its hydrate, potassium dichloroisocyanurate, and the like.

The raw material used in the present invention is a wet cake obtained by dehydration and separation from a slurry obtained in a conventional industrial process for producing solid chlorine agents. The moisture content of this wet cake usually ranges from 10 to 40% by weight.

In the method of the present invention, granules are formed into spherical shapes after extrusion granulation, but if the wet cake is directly granulated into spherical shapes, it becomes a lumpy, non-uniform mass. , it turns into powder. However, if a wet cake is extruded and then granulated into a spherical shape, it is possible to obtain spherical granules that are strong and do not powder at all, and also have almost no powdering during the subsequent drying process or during the transfer of the granules. It will be done. The obtained granules have a spherical shape with a uniform diameter that is desirable in appearance, have high free-flowing properties, and have a fast dissolution rate.

The diameter of the spherical granules of solid chlorine agent obtained by the method of the present invention is determined depending on the diameter of the small holes used in extrusion granulation. The diameter of the spherical granules is preferably 0.2 to 5 mm, and the more preferred diameter is 0.4 to 2 mm. Therefore, the diameter of the small holes of the extrusion granulator used is 0.2 to 5 mm, preferably 0.4 to 2 m.
It is m. A diameter of 0.2 to 5 mm obtained by this extrusion granulation,
The desired spherical granules can be obtained by granulating the wet columnar molded product, preferably 0.4 to 2 mm, into a spherical shape using a rolling granulator or a spherical granulator.

The extrusion granulator used includes a screw type extrusion granulator, a roll type extrusion granulator, a blade type granulator, etc., but a screw type extrusion granulator is preferable.

In addition, as a granulator for spherical granulation, a rolling granulator or
Examples include spherical sieving machines. As the rolling granulator, a drum-type and a plate-type granulator are preferred. The spherical granulator is sold under the name Marumerizer.

This is a horizontally rotating grooved plate that uses centrifugal force and frictional force due to the unevenness of the plate to turn wet granules into spheres, forming a doughnut-like shape on the inner wall of the casing and twisting it like a rope thread. It has a mechanism that allows it to rotate and become spherical.

The granules thus granulated into spherical shapes are dried, and although there are various drying methods, a fluidized drying method is preferred.

When obtaining dichloroisocyanuric acid dihydrate etc., this drying must be carried out at a temperature of 45 to 55°C, which is a temperature range that does not cause desorption of water of crystallization. For agents, the temperature may be higher than this, but the preferred temperature in this case is 70 to 110°C. It is desirable that the content of free water in the solid chlorine agent be 2% or less during this drying.

The bulk density of the spherical granules of the solid chlorine agent obtained in this way varies somewhat depending on the solid chlorine agent, but in the case of a chlorinated isocyanuric acid compound, it is 0.5 to 0.9 g/cm',
The bulk density of highly bleached powder is 0.7 to 1.0 g/cm', which is lower than the bulk density of granules obtained by dry granulation.

The granules obtained by the method of the present invention have a high surface hardness, but are porous inside, and therefore have a lower bulk density than dry granulated products, do not become powdery, and have a significantly faster dissolution rate in water. Become. Furthermore, because of the spherical shape, the granules have high fluidity and are extremely easy to transport, measure, and handle.

At the time of granulation, it is a preferable embodiment to add a commonly used binder to increase the hardness of the granules, or to add a lubricant such as stearate or orthoboric acid to reduce friction during extrusion molding. be.

Furthermore, when the particles are formed into spherical particles using a rolling granulator or a spherical granulator, by adding pigments, fragrances, coating agents, etc., the particles can be colored, coated, coated, or multilayered.

The present invention will be explained in more detail below with reference to Examples, but the technical scope of the present invention is not limited thereto.

Example 1 Sodium dichloroisocyanurate in a wet state with a water content of 21.6% by weight was extruded into an extrusion granulator (Pelletable EXD-60 manufactured by Fuji Paudal Co., Ltd.). This equipment was also used in the following Examples and Comparative Examples. ) using 50-60
At a granulation rate of kg/hour, about 20 kg of wet cylindrical core particles with a diameter of 1.0 mm and a length of 2 to 5 mm were obtained. The cylindrical grains were processed into 0.5k particles at a time using a spherical particle sizer (Marmerizer-Q-23 (manufactured by Fuji Paudal Co., Ltd.; this device was also used in the following Examples and Comparative Examples).
g was charged, and wet spherical particles with a diameter of 1.0 to 1.8 mmφ were obtained in about 2 minutes. The wet spherical particles are then dried in a fluidized dryer (Midget Dryer manufactured by Fuji Paudal Co., Ltd.).
MD-A-200 This fluidized dryer was also used in the following Examples and Comparative Examples.

), 0.8 kg was charged at a time in 5 to 15 minutes, and the hot air at the inlet was blown at a temperature of 85 to 95° C. for drying.

The drying was completed at the point where the temperature of the exhaust gas started to rise rapidly. 0 When the water content of the spherical particles was high, the temperature of the exhaust gas at the outlet was 30 to 40°C. There was almost no powdering during this drying.

Moisture content i10.7% by weight, bulk density 0.69g/cm3
, spherical particles of sodium dichloroisocyanurate with a diameter of 1.0 to 1.8 mmφ were obtained.

Example 2 The same procedure as in Example 1 was carried out using the same raw materials.

However, the diameter in extrusion granulation is 2.0 mmφ, and the length is 3
Cylindrical grains of 5-7 mm were produced. There was almost no powdering during fluidized drying. Moisture content 0.5% by weight, bulk density 0.
Spherical particles of sodium dichloroisocyanurate weighing 67 g/cm3 and having a diameter of 2.0 to 3.4 mm were obtained.

Example 3 Example 1 except that sodium dichloroisocyanurate in a wet state with a moisture content of 126.4% by weight was used as the raw material.
I did the same thing. There was almost no powdering during fluidized drying. Moisture content 10.7% by weight, bulk specific gravity 0.67 g/cm3,
Spherical particles of sodium dichloroisocyanurate with a diameter of 1.0-1.7 mmφ were obtained.

Comparative Example 1 The diameter obtained with the extrusion granulator used in Example 1 was 1.0 mmφ
Wet cylindrical grains with a length of 2 to 5 mm were directly air-dried at an inlet temperature of 85 to 95°C without granulation using a spherical granulator, but almost all of them were powdered. Ta.

Comparative Example 2 The raw material used in Example 1 was directly granulated using a spherical granulator without extrusion granulation. The granules adhered to the walls and bottom of the spherical granulator, and only agglomerated and non-uniform granules with a size of 2 to 50 mm were obtained.Furthermore, although it was dried at an inlet temperature of 85 to 95°C, almost all of the granules were powdered.

Example 4 The same procedure as in Example 1 was carried out using the same raw materials.

However, the inlet gas temperature during fluidized drying was 45 to 55°C. There was almost no powdering during fluidized drying. Bulk density 0゜78g/c
Spherical particles of sodium dichloroisocyanurate dihydrate having a diameter of 1.0 to 1.7 mm mφ were obtained. The water content was 13.9% by weight including crystal water.

Example 5 The same procedure as Example 4 was carried out. However, the diameter is 2.0 due to extrusion granulation.
Cylindrical grains with a length of 3.5 to 7 mm were produced. There was almost no powdering during fluidized drying. Bulk density 0.77
g/cm' and a diameter of 2.0 to 3.4 mm, spherical particles of sodium dichloroisocyanurate dihydrate were obtained. The water content was 13.5% by weight including crystallization water.

Comparative Example 4 The cylindrical granules obtained in Example 4 were directly fluidized and dried at an inlet temperature of 45 to 55°C without granulation using a spherical granulator to form granules of dichloroisocyanuric acid dihydrate. I tried to get it, but almost all of it turned into powder.

Example 6 The same procedure as in Example 1 was carried out except that trichloroisocyanuric acid in a wet state with a water content of 15.2% by weight was used. There was almost no powdering during fluidized drying. Bulk density 0.85g/c
m3, moisture content 0.3% by weight diameter 1.0 = 1.7
Spherical particles of trichloroisocyanuric acid of mm mm were obtained.

Example 7 The same procedure as in Example 1 was carried out except that potassium dichloroin cyanurate in a wet state with a water content of 20.7% by weight was used. There was almost no powdering during fluidized drying. Bulk density 0.7
9g/cm', moisture content 0.4% by weight, diameter 1.0~
Spherical particles of potassium dichloroisocyanurate with a diameter of 1.7 mm were obtained.

Example 8 The same procedure as in Example 1 was carried out except that highly bleached powder in a wet state with a water content of 22.4% by weight was used. There was almost no powdering during fluidized drying. Spherical grains of highly bleached powder having a bulk density of 0.85 g/cm3, a water content of 1.7% by weight, a diameter of 1.0 to 7 mm were obtained.

Comparative Examples 6-7 The cylindrical grains obtained in Example 6.7.8 were directly heated to an inlet temperature of 85 to 95°C without being granulated using a spherical granulator.
Although it was fluidized and dried, the entire amount turned into powder.

Comparative Examples 8 to 10 The wet cakes used in Examples 6, 7, and 8 were granulated in a spherical granulator without extrusion granulation. As in Comparative Example 2, only lumpy and non-uniform granules with a size of 2 to 50 mm were obtained, and the inlet temperature was 85 to 95 mm.
Although it was dried at ℃, the entire amount turned into powder.

[Evaluation of dissolution rate of granules]

(a) Preparation method of granules for dissolution rate measurement For comparison, granules were produced by a dry method as follows.

Powder of sodium dichloroisocyanurate (150 mesh bath product) with a water content of 1.4% by weight is processed using a roller compactor with a roll rotation speed of 15 times/min and an oil pressure of 75 kg.
/cm", a compression pressure (linear pressure) of 1°5 tons/cm, and a granulation rate of 90 kg/hour to obtain a plate-shaped molded product with a width of 60 mm and a thickness of 1.5 mm, which was further crushed and passed through a sieve. Sort the particles,
Granules of 990-1400μ were obtained.

In the same manner, granules of dichloroisocyanuric acid dihydrate, trichloroisocyanuric acid, potassium dichloroisocyanurate, and highly bleached powder were obtained by the dry method.

The thus obtained granules and the spherical granules obtained in the examples were placed in a 12 mesh (1400μ) bath and a 16 mesh (
The mixture was classified using a 990μ) Stop sieve to make the particle size uniform and used as a sample for measuring the dissolution rate.

(b) Method for evaluating dissolution rate 0.5 g of each granule shown in Table 1 was added to distilled water in step 11, stirred with a constant speed stirrer, and filtered at each time shown in Table 1. The available chlorine concentration was measured using the iodometry method.

The dissolution rate was determined from this measured value and the theoretical value of available chlorine at the time of complete dissolution. The results are also shown in Table-1.

As shown in Table 1, the solid chlorine agent granules obtained by the method of the present invention have a faster dissolution rate than the solid chlorine agent granules obtained by the conventional dry method.

Claims (7)

[Claims] (1) In a method for producing granules of a solid chlorine agent from a wet cake obtained in the manufacturing process of a solid chlorine agent, (a) a wet cake is extrusion granulated to have a diameter of 0.2 to
(c) After granulating the columnar granules into spherical particles with a diameter of 0.2 to 5 mm using a rolling granulator or a spherical granulator, (c) ) A method for producing spherical granules of a solid chlorine agent, comprising the step of drying. (2) The method for producing spherical granules of a solid chlorine agent according to claim 1, wherein the solid chlorine agent is a chlorinated isocyanuric acid compound. (3) Claim 2, wherein the chlorinated isocyanuric acid compound is at least one compound selected from trichloroisocyanuric acid, sodium dichloroisocyanurate anhydride or its hydrate, and potassium dichloroisocyanurate. A method for producing spherical granules of a solid chlorine agent as described in . (4) The method for producing spherical granules of a solid chlorine agent according to claim 2, wherein the spherical granules of the chlorinated isocyanuric acid compound have a bulk density of 0.5 to 0.9 g/cm^3. (5) Claim 1 in which the solid chlorine agent is highly bleached powder
A method for producing spherical granules of a solid chlorine agent as described in . (6) Bulk density of spherical granules of highly bleached powder is 0.7 to 1.0
The method for producing spherical granules of solid chlorine agent according to claim 5, wherein the solid chlorine agent has a particle size of 3 g/cm^3. (7) The method for producing spherical granules of solid chlorine agent according to claim 1, wherein the moisture content of the wet cake is 10 to 40% by weight.