JPH0674143B2 - Method and apparatus for removing deposits and inclusions of natural zeolite - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICATION Field of the invention The present invention relates to a natural zeolite pulverized to a particle size of 0.2 to 10.0 mm.
The present invention relates to a method and an apparatus for promoting the enhancement of compression strength and activation by heating in an air atmosphere in a temperature range of 00 to 600 ° C. to remove adhered and / or contained water and adhered solid fine particles. .

As is well known in the prior art, natural zeolite has high-quality deposits in many parts of Japan, has a large reserve, and can be easily mined. It is used for processing.

A rotary kiln is generally used as a processing device for activating natural zeolite, but its processing technology is insufficient, and technical information and exchanges are insufficient because the demand area is limited to the production area. is doing.

For this reason, it is known that natural zeolite has high heat resistance and chemical resistance, but no treatment method to make use of these characteristics is known, and expensive activated carbon or synthetic zeolite was used. .

On the other hand, it is widely known that the adsorbents that are often used nowadays mainly include activated carbon and have an excellent adsorption ability. As the capacity of the adsorbent, it is strongly required that it can be manufactured at a low cost, that it has excellent adsorption performance, that it has high activity and can be reused, and that it has high heat resistance and chemical resistance. However, activated carbon is relatively expensive, and there is a limit to the adsorbed material because it has only physical properties, and heat resistance is a constant temperature of up to 300 ° C, and regeneration is expensive. On the other hand, in general, when using natural zeolite for industrial purposes, the biggest concern is that adhered solid fine particles generate sludge when they come into contact with water and lose transparency of water, and when gas is passed, the adhered solid fine particles become atmospheric. There is a problem that they scatter inside and become dust and generate secondary pollution. Therefore, conventionally, there has been a problem in that it is necessary to immerse the natural zeolite in water or a solvent in advance to remove the adhered solid fine particles and impurities and then to calcinate, which is costly.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention As a result of repeated investigations on various treatment methods and apparatuses for compensating the drawbacks of activated carbon and the like, the present inventors carried out a simple treatment of a large amount of natural zeolite buried in Japan. It is active as an adsorbent by performing dehydration of adhering and / or water content contained therein and removing adhering solid fine particles by treatment with a method and a treating device, and physical and chemical adsorption can be exerted, high heat resistance, and recycle use The present invention has been achieved based on the finding that a substance capable of achieving the above can be obtained.

Means for Solving the Problems The present invention solves the above problems by heating a natural zeolite having a particle size of 0.2 to 10.0 mm to 400 to 600 ° C. in an air atmosphere to cause adhesion and / or
Or, a method for removing deposits and inclusions of natural zeolite, characterized by performing dehydration of contained water and separation of adhered solid fine particles, and a raw material supply unit for supplying natural zeolite having a particle size of 0.2 to 10.0 mm, and this raw material 400 packed bed in air atmosphere
A reaction tube that heats up to ~ 600 ° C to dehydrate adhered and / or contained water and separate adhered solid fine particles, a dispersion plate that introduces air to the bottom of the packed bed, and a fired product that removes the fired product from the center of the dispersion plate An explanation will be given using a device for removing the deposits and inclusions of natural zeolite, which is composed of a take-out section.

Operation The present invention is intended for clinoptilolol fluorstone and morden fluorstone, which are inexpensive and easily obtainable among natural zeolites, and have a simple treatment method and apparatus for adhering and / or containing water and adhering solid fine particles in an air atmosphere. It is heated to 400-600 ℃ and dehydration and separation of solid fine particles are carried out at the same time. That is, removing the natural zeolite adhesion and water content increases the pore diameter by removing the water content present in the pores without destroying the crystal structure. Separation of adhered solid particles is to make the surface of natural zeolite a material rich in ridges. In the method according to the present invention, natural zeolite pulverized to a particle size of 0.2 to 10.0 mm is filled in a cylindrical container, and the outer periphery thereof is heated by a heat heater or the like.
The sample is supplied and discharged while keeping the packed bed height and the residence time constant in an air atmosphere while heating at 0 to 600 ° C.

As a result, the supplied natural zeolite packed bed undergoes a three-stage thermal covering history from the top to become an activated material.

The first stage occurs in the first zone from the top of the packed bed of natural zeolite up to about 25% of the packed bed height. In this region, the supplied natural zeolite is heated to about 120 ° C in the lower part of the packed bed by preheating accompanying heating. As a result, water adhering to the natural zeolite and solid fine particles are dehydrated. Subsequently, the second step is carried out in the second area 38% downward from the first area. At this stage, the natural zeolite is heated to 380 ° C. and dried by preheating from the lower part of the packed bed as in the first stage, and the water content is dehydrated and the solid fine particles are separated. Further, in the third region, which is 37% downward from the second region, the separated solid fine particles serve as a heat medium while flowing between the natural zeolite particles, thereby keeping the natural zeolite particles at 400 to 600 ° C.
A third firing step of heating to 100 ° C. is performed.

In order to explain each step below in more detail,
In the area, the waste heat in the air stream with a linear velocity of 40 cm / sec (20 ° C) supplied from the third baking area and the second drying area is effectively used to disperse the adhering water as vapor into the atmosphere. Let In the second region, the contained water is dehydrated and the attached solid fine particles are separated without destroying the pore structure inside the natural zeolite itself, and the natural zeolite is changed into a porous state. Further, in the third calcination zone, the surface ridges of the dried natural zeolite and the voids and pores inside thereof are strengthened to promote the activation.

Thus, according to the present invention, the height of the packed bed of natural zeolite is kept constant, the raw material is continuously supplied in the air atmosphere, the deposit is dehydrated,
(EN) A series of treatment methods for drying, separating and firing adherents, activating and then discharging, and a treatment apparatus therefor.

Example Hereinafter, the apparatus of the present invention will be described based on an illustrated example.

In FIG. 1, reference numeral 1 is a natural zeolite adhesion / inclusion removal apparatus, and a raw material supply unit 2 is provided above the adhesion / inclusion removal container 1. The natural zeolite supplied from the raw material supply unit 2 forms the packed bed 3 having a height of about 400 mm. In this packed bed 3, about 25% of the height of the packed bed from the upper end forms the dehydration part 4 of the deposits, and about 38% below the dehydration part 4 is formed.
% Is the area of the drying section 5 where the water content is dehydrated and the solid fine particles are separated, and about 37% below the drying section 5 is the baking section 6.

The heating of the packed bed 3 of natural zeolite is carried out from the heat heater 7 and the air inlet 8 provided on the outer wall of the apparatus at a flow rate of 40 ml / min.
It is introduced at (20 ° C.) and heated to a set temperature and is made by an air flow passing through the dispersion plate 9, which promotes the role of separating and dewatering solid particles. The separated solid fine particles hardly scatter at the introduced air flow rate, but the dehydrated water vapor is collected as water together with a few fine particles discharged from the cyclone 10.

On the other hand, the natural zeolite fired in the firing unit 6 is
An activated natural zeolite is obtained which is discharged through a discharge pipe 12 connected to 11.

A thermocouple 13 controls the temperature of the firing section 6 in the packed bed 3 of natural zeolite.

The calcined natural zeolite can be sieved to a particle size suitable for the intended use.

That is, the natural zeolite packed in one cylinder is repeatedly supplied and discharged while always maintaining a constant height of the packed bed, and the water and solid particles adhering from the upper surface of the packed bed are dehydrated. The dehydration step of the water content and the drying step in which the solid fine particles are separated, and the firing step of heating the dried material by raising the temperature are continuously performed.

The heat source for heating is also used to heat the natural zeolite in the calcination zone and at the same time to heat the introduced air. Therefore, after the firing step, the heat quantity is effectively utilized for heating in the drying step and the dehydration step in order.

EFFECTS OF THE INVENTION Next, the experimental results of treating natural zeolite adhesion / inclusions using the adhesion / inclusion removing apparatus according to the present invention will be shown.

1) Adhesion / inclusion removal device for natural zeolite This is a steel adhesion / inclusion removal device having a structure similar to that of the illustrated embodiment, wherein the height of the deposit and inclusion removal device container is 700 mm, and the inside diameter is 110 mm. And the height of the packed bed of natural zeolite is 4
It was set to 00 mm.

2) Raw material used Natural zeolite (clinoptyrolite) having a particle size of 0.2 to 10.00 mm was charged into the raw material supply unit 2 at a treatment rate of 2.0 kg / h. The charged raw materials are supplied to the packed bed 3 in the adhesion / inclusion removal device 1, where they are sequentially dehydrated, dried, and fired to become products. The analysis results of the obtained natural zeolite are shown below.

(1) Outflow rate of adhered solid fine particles In this device, natural zeolite is calcined for 1 hour at each temperature, and 300 g of particles of 0.2 mm or more is soaked in 1 water for 20 hours. Was measured.

The outflow rate changed as shown in Table 1.

From Table 1, it is confirmed that the proportion of solid fine particles flowing out as a result of the treatment according to the present invention is significantly reduced. In other words, it can be seen that the fine particles are effectively separated from the natural zeolite supplied by the treatment according to the present invention.

Furthermore, the baking time and the measurement conditions of the outflow rate are the same,
At a firing temperature of 500 ° C, the heating device was changed to an electric furnace and the outflow rate was measured.

The outflow rate changed as shown in Table 2.

From Table 2, it is confirmed that the treatment in this apparatus can separate the solid fine particles more effectively than the treatment using the ordinary electric furnace.

(2) Compressive strength A natural zeolite sample processed into a rectangular body of 10 mm × 10 mm × 20 mm in this device was calcined for 1 hour at each temperature, and the compressive strength was measured by an Instron tester.

The compressive strength changed as shown in Table 3.

From Table 3, it can be seen that, as a result of the treatment according to the present invention, the compressive strength of the obtained natural zeolite is significantly improved.

(3) Comparison of CO ₂ adsorption retention time In this device, natural zeolite calcined at each temperature was pulverized to 0.1 to 0.5 mm, packed into a column, and CO ₂ adsorption retention time was measured by gas chromatography. . However, the measurement conditions are column content: 4 mm, length: 360 mm, analysis temperature: 30
C, carrier gas: helium, flow rate: 25 ml / min, CO ₂ purity: 99.5% or more, injection amount: 5 cc.

Further, the same method was used for comparison with activated carbon (in this case, the packing amount in the column was the same).

The CO ₂ adsorption retention time changed as shown in Table 4.

As can be seen from Table 4, it has been found that the best, in other words, the longest CO ₂ adsorption time is obtained at the firing temperature of 500 to 570 ° C.

Natural zeolite (calcination temperature 500-570 ℃) and activated carbon CO ₂
The adsorption retention time of each was compared. The results are shown in Table 5.

As is clear from Table 5, the natural zeolite treated by the method and apparatus of the present invention has a significantly higher CO 2 than activated carbon.
₂ Adsorption retention time is shown.

According to the present invention, a natural zeolite having a particle size of 0.2 to 10.0 mm is heated to 400 to 600 ° C. in an air atmosphere, and adhesion and / or dehydration of contained water and separation of adhered solid particles are carried out to obtain adhered solid particles. Is small, the compression strength is large, CO
Long ₂ adsorption retention time, it is possible to obtain a natural zeolite having the excellent CO ₂ adsorption retention properties than the activated carbon.

[Brief description of drawings]

FIG. 1 is a schematic view of a zeolite adhering and inclusion removing apparatus according to the present invention. 1 ... Container, 2 ... Raw material supply section, 3 ... Packed layer, 4 ...
Dehydration part, 5 ... Drying part, 6 ... Firing part, 7 ... Heater, 8 ... Air inlet, 9 ... Dispersion plate, 10 ... Cyclone.

Claims (2)

[Claims] 1. A natural zeolite characterized by heating natural zeolite having a particle size of 0.2 to 10.0 mm to 400 to 600 ° C. in an air atmosphere to dehydrate adhering and / or contained water and separate adhering solid fine particles. Method for removing adhered substances and inclusions. 2. A raw material supply section for supplying natural zeolite having a particle size of 0.2 to 10.0 mm and a packed bed of this raw material in an air atmosphere.
A reaction tube that heats to 400 to 600 ° C to dehydrate the adhering and / or water content and separate the adhering solid fine particles, a dispersion plate that introduces air to the bottom of the packed bed, and take out the calcined product from the center of the dispersion plate. An apparatus for removing deposits and inclusions of natural zeolite, which comprises a calcined product take-out section.