JPH0427361A - Production of granulated salt - Google Patents

Abstract

PURPOSE:To obtain the title salt containing calcium as mineral, resistant to moisture and caking by melting a mixture comprising common salt and a calcium compound at elevated temperatures and by injecting the melt through a nozzle into a granular product. CONSTITUTION:A mixture comprising >=70 pts.wt. of common salt and >=30 pts.wt. of a calcium compound (e.g. calcium carbonate) is melted at 650-850 deg.C, and the resulting melt is injected through a nozzle into a granular product, thus giving the objective granulated salt.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing granulated salt, and in particular, a method for producing granulated salt, in which powder particles of a calcium compound such as calcium carbonate are dispersed inside fine granular solids of common salt. The present invention relates to a method for producing granulated salt.

[Prior Art] Minerals are called inorganic substances or ash, and are important elements constituting the human body. Examples of these minerals include phosphorus, calcium, iron, iodine, copper, manganese, magnesium, fluorine, cobalt, zinc, and molybdenum. These minerals in the body, like other nutrients, are constantly metabolized. For example, sodium, potassium, magnesium, calcium, etc. are secreted and excreted every day as hydrochlorides, sulfates, and phosphates in fixed amounts through urine, sweat, etc. Intake is required.

In particular, calcium and iron are minerals that are easily deficient in daily life, and adults have CaO, 6g/day, and F.
ed, otg/day is required. Therefore, among minerals, it is especially important to efficiently ingest calcium and iron, especially calcium.

Calcium is contained in large amounts in bone-in fish, dairy products, and vegetables. Therefore, it is desirable to intake calcium evenly from these foods, and recently the intake of bone-in fish and vegetables has been decreasing. Therefore, if common salt containing calcium is provided, calcium can be ingested at the same time as common salt is used, which is very advantageous.

By the way, the current method of manufacturing salt in Japan is as follows:
A method is used in which seawater is concentrated using an ion exchange membrane and then concentrated and crystallized using an evaporator. On the other hand, in other countries, rock salt is mined, seawater is concentrated by the sun,
A method of crystallization has also been adopted. Furthermore, in order to obtain higher purity common salt, it is purified by dissolving rock salt or salt obtained by concentration or crystallization and recrystallizing it.

The crystal form of the purified salt obtained by this recrystallization is cubic. Note that in some cases, minerals are added during such purification.

[Problem to be solved by the invention] Conventionally, refined salt produced by adding minerals has a high purity of salt, mostly composed of sodium chloride (NaCl2). ■ Calcium, iron. It contains only small amounts of minerals such as , magnesium, and potassium.

■ Easy to absorb moisture and solidify.

There were drawbacks such as.

The object of the present invention is to solve the above-mentioned conventional problems and provide a method for producing a granulated salt that contains a large amount of minerals, has low hygroscopicity, and is solidified and granulated.

[Means for Solving the Problems] The method for producing granulated salt of the present invention comprises preparing a mixture containing 70 parts by weight or more of common salt and 30 parts by weight or less of a calcium compound.
It is characterized by melting at a temperature of ~850'C and injecting the melt through a nozzle to form granules.

The present invention will be explained in detail below.

There are no particular restrictions on the salt used in the present invention,
It may be ordinary table salt or its purified salt, or table salt whose ingredients have been prepared.

Further, examples of the calcium compound include calcium carbonate, calcium phosphate, etc., or substances containing these calcium compounds. These may be natural products or synthetic products. For example, since calcium carbonate is contained in limestone, shells, coral, blue powder, etc., pulverized products of these materials may be used. Alternatively, it may be synthesized by chemically reacting with the reaction of 1. Ca (OH) 2 + CO 2 - CaCO 3 + H 20. As calcium phosphate, in addition to synthetic products, bone powder can also be used. If the particle size of these calcium compounds or calcium compound-containing substances is too large, it will be difficult to contain them in a well-dispersed state in the resulting granulated salt. Therefore, it is desirable that the particle size of the calcium compound or calcium compound-containing substance be 10 μm or less, preferably 0.1 to 5 μm.

In the present invention, 70 parts by weight or more of common salt and 30 parts by weight or less of a calcium compound are mixed. Here, if the amount of common salt is less than 70 parts by weight, it is difficult to form granulated salt. However, if the proportion of common salt is too high, the purpose of the present invention, which is to contain a large amount of calcium compounds, cannot be achieved. It is preferable to mix.

In addition, in the present invention, other additives may be mixed in addition to the common salt and the calcium compound within a range that does not impair the purpose of the present invention.

6. A mixture containing a predetermined amount of common salt and a calcium compound.
Melts at temperatures between 50 and 850'C. This melting temperature varies depending on the NaCJ2 purity of the salt used, and the NaCJ
2 Those with lower purity can be melted at lower temperatures. In this melting, it is important that only the common salt is melted and the calcium compound is neither melted nor decomposed. In particular, when calcium carbonate is used as the calcium compound, 83
Preferably, it is melted at a temperature below 0'C.

The melt is sprayed using a high-pressure nozzle to form fine granulated salt. Although the particle size of this granulated salt varies depending on the type of nozzle and the pressure of the high-pressure fluid (high-pressure air) used for spraying, it is usually preferable to use a granulated salt with a particle size of 100 to 500 μm.

[Effect] Common salt differs depending on its composition, but most salt has 804
Melts at temperatures below °C. That is, sodium chloride (Na
The melting point of CJ2) is 804°C, and in table salt containing a small amount of potassium chloride (KCJ2), etc., this Na
It melts at a temperature lower than the melting point of CJ2, 804°C. On the other hand, the melting point of mineral components such as calcium carbonate is higher than that of common salt.

In the present invention, by utilizing the difference in melting point between common salt and a calcium compound, a mixture containing common salt and a calcium compound is melted at a temperature of 650 to 850°C, where common salt melts but calcium compounds do not melt or decompose. Then, by spraying this from a nozzle, granulated salt is produced in which salt is encapsulated in calcium compound powder, specifically, calcium compound powder particles are dispersed and contained inside the fine granular solids of salt. Manufacture granulated salt.

In the method of the present invention, a larger amount of calcium compound can be contained in the granulated salt than in the conventional method.

Furthermore, because it melts at high temperatures, unlike conventional common salt, it is difficult to absorb moisture and hard to solidify. Moreover, since the grains are approximately spherical in shape, they have good fluidity in handling and have high commercial value.

[Example] The present invention will be described in more detail with reference to Examples and Experimental Examples below.

Examples 1 to 5 Salt, calcium carbonate, etc. were mixed to obtain mixed raw materials having the formulations shown in Table 1. This was melted in a melting furnace at the temperatures shown in Table 1, and the melt was sprayed from a nozzle (fluid nozzle type) using high-pressure air to obtain granulated salt with the particle size shown in Table 1. . In addition, calcium carbonate (CaCO
For 3), shells with a particle size of 0.6 to 2 μm were used, and primary tricalcium phosphate was used as the calcium phosphate.

The obtained granulated salts each contained powder particles of minerals such as calcium and phosphorus in a dispersed state inside the fine granular solids of common salt, and the shape was approximately spherical.

Experimental Example 1 Granulated salt produced in Example 1 (particle size 200-500 μm)
, silk salt (table salt) (particle size 150-500 μm) and bittern-containing salt (normal salt dried at 100°C) (particle size 15
0 to 600 μm), the hygroscopicity was investigated by measuring the moisture absorption rate.

To measure the moisture absorption rate, put a weighing bottle containing 15 g of winter water into a desiccator containing saturated saline, and set the temperature at 20 to 25°C.
The weight change due to moisture absorption of the salt was measured over time at a humidity of 70%.

The results are shown in Table 2.

From Table 2, it is clear that the granulated salt produced according to the present invention has low hygroscopicity, is difficult to consolidate, and has excellent handling properties.

[Effects of the Invention] As detailed above, according to the method for producing granulated salt of the present invention, it contains a large amount of calcium, which is the most essential mineral among minerals, and has a substantially spherical shape that is resistant to moisture. Since it is difficult to caking, it provides a granulated salt that is very easy to use and has a high commercial value.

Claims (1)

[Claims] (1) Granulation characterized by melting a mixture containing 70 parts by weight or more of common salt and 30 parts by weight or less of a calcium compound at a temperature of 650 to 850°C, and injecting the melted material from a nozzle to form a granulated product. Method of manufacturing salt.