WO2014051187A1

WO2014051187A1 - Method for molding pellet-shaped catalyst or ceramic by using pressing apparatus

Info

Publication number: WO2014051187A1
Application number: PCT/KR2012/008029
Authority: WO
Inventors: 이승주; 정유식; 조종훈; 정희영
Original assignee: (주) 뉴웰
Priority date: 2012-09-28
Filing date: 2012-10-04
Publication date: 2014-04-03
Also published as: KR101297415B1

Abstract

The present invention relates to a method for molding a pellet-shaped catalyst or ceramic by using a pressing apparatus, and more specifically, to a method for molding a pellet-shaped catalyst or ceramic by using a pressing apparatus, which inserts a mixture of the catalyst or ceramic into a mold provided with a plurality of through-holes, and then dries and molds same into pellet shapes, thereby changing the shape of pellets without expensive equipment while providing pellets having a uniform size.

Description

Pellet-type catalyst or ceramic forming method using a press device

The present invention relates to a pellet-type catalyst or ceramic molding method using a press device, and more particularly, by inserting a catalyst or ceramic dough into a mold having a plurality of through-holes by pressing and drying them to form a pellet. The present invention relates to a pellet-type catalyst or ceramic molding method capable of providing pellets of uniform size while variously changing the shape of the pellets without expensive equipment.

Catalyst and ceramic production are usually made in powder form. These powdered catalysts and ceramics must be shaped to the desired shape required under practical conditions. Particularly, if the catalyst is provided in the form of powder, it is difficult to control the reaction of the catalyst in the reactor, a large pressure loss appears, and may cause contamination of the reactor and other devices due to the catalyst powder.

The catalyst and the ceramic are generally molded into pellets using a tableting machine or an extruder.

The tableting machine is mainly used to make a pellet catalyst or ceramic, and has the advantage of providing a strong mechanical strength. Such a tablet press is a machine that injects powder into a molding mold using a high pressure molding machine and then continuously forms a catalyst and a ceramic using a strong pressure. The tableting machine can perform a continuous molding operation, the catalyst and the ceramic powder can be used directly, the pretreatment is relatively easy, and the molded catalyst and ceramic are often not required to remove the binder or foreign matter. However, the value of the machine and accessories are expensive, the processing of the molding die is difficult, and once manufactured molding die has a disadvantage that it is difficult to provide a variety of molding forms because it is difficult to rework in a different shape.

Next, the extruder includes a screw extruder of a continuous type and a press extruder of a batch type. The screw extruder enables the extrusion process by continuously performing the kneading process and the extrusion process of the catalyst and the ceramic powder at the same time. However, in order to mold the catalyst and the ceramic in the screw extruder, a binder must be used, and since the binder is removed by the binder, the mechanical strength may be lower than that of the catalyst and the ceramic prepared by the tablet. In spite of these disadvantages, the screw extruder can be formed into pellets in various forms by changing the nozzle, and is one of the molding methods that are widely used because the nozzle processing is inexpensive.

However, the catalyst and ceramic extruded from the extruder are generally continuously formed into a long rod shape, and it is difficult to manufacture a cutter that cuts it to a desired length. At present, a cutting machine capable of cutting the extruded catalyst and ceramic includes a chopping machine that randomly cuts the machine, which does not control the length of the catalyst and the ceramic constantly. In addition, there is a defibrillator to make a certain spherical shape, which has the disadvantage that can only make a spherical shape. Therefore, if necessary, the extruded catalyst and ceramics may be dried well after extrusion for a long time, and then the length may be cut by hand manually. However, this task is manual and it is very difficult to work with a large amount constantly.

In the extrusion method of the catalyst for internal reforming of a molten carbonate fuel cell of Patent Application No. 10-2009-0090208, a method of cutting the extruded catalyst by a string. In the known patent, the catalyst is molded in a straight form during extrusion and then cut into thin wires such as a piano wire or a fishing line by putting it in a cutter frame. This method can cut the catalyst to the desired length, but the operation time is very slow because it is manual.

In spherical solid fuel pellets and a method of manufacturing the patent application of the patent application 10-2010-0045591, a method of forming a solid fuel in the form of a spherical pellets using a recirculator, the recirculator used can quickly produce a large amount of pellets If the shape is formed on the ventilation surface, for example spherical, only spherical shape can be produced. Of course, if the roll of the machine is changed to a roll formed with a groove of a different shape, it is possible to produce different types of pellets, it is difficult to provide in various forms because the roll itself is expensive.

As described above, the pelletizing machine and the extruder used to manufacture the catalyst and the ceramic in the pellet form are expensive equipments and are difficult to use.In the case of the tableting machine, there are disadvantages in that the machine is complicated and the mold processing is difficult. In this case, continuous operation is possible, but it is difficult to fit a certain size due to the lack of a technology for cutting the extruded catalyst or ceramic.

Therefore, there is a need for a method for producing a pellet-type catalyst and ceramic having a uniform size without using such an expensive tabletting machine and an extruder.

In the pellet-type catalyst or ceramic molding method using the press apparatus of the present invention,

Providing a method for producing various types of pellets at a low cost by forming a pellet shape by using a mold of a plate that is easily formed through various types of holes, and adding a catalyst or ceramic dough into the holes. The purpose.

Another object of the present invention is to provide a method of reducing the production cost by minimizing the amount of dough residue during the manufacturing process while providing pellets having a thin and high strength which cannot be manufactured by tableting. .

Pellet-type catalyst or ceramic molding method using the press apparatus of the present invention for solving the above problems,

Catalyst or ceramic pellets using a press made of a press located in a table and an upper part spaced apart from the table surface by pressing, and a forming mold placed on the table of the press and having a plurality of holes formed therein. 1. A method of molding a method comprising: mixing a catalyst or a ceramic powder and a binder and kneading the same to prepare a dough; Placing the prepared dough on an upper part of a mold formed with a plurality of through holes; Operating the press to press the dough into a pressurized dough so that the dough is introduced into the through hole of the mold; Returning the press presser to press to the original position, and removing the residual dough placed outside the through hole of the mold by a scraper; A drying pellet receiving step of drying the molding mold from which the residual dough is removed, wherein the dough material of the through-hole of the molding mold is separated from the molding mold by moisture evaporation and received in pellet form; It comprises a baking step of removing the binder by applying heat to the dried pellets.

Pellet-type catalyst or ceramic molding method using the press apparatus of the present invention by the above solution means,

The catalyst or ceramic dough is pressed into a plurality of holes formed in the mold while pressing to form a dense structure of the dough in the hole, and the volume decreases due to water evaporation during the drying process, so that the inner wall of the hole of the mold is naturally formed. The separation allows the production of catalysts or ceramic pellets at low cost.

In addition, even when the pellet is formed to a thin thickness it is possible to provide a useful method to be used in a variety of fields by maintaining a high strength by the press is made by the press.

1 is a block diagram showing a pellet forming process according to an embodiment of the present invention.

2 to 6 is a schematic diagram showing a pellet forming process according to an embodiment of the present invention.

7 is a plan view showing a mold according to an embodiment of the present invention.

10: forming mold

11: through-hole

20: table

30: pressurizing table

40: dough

50: scraper

60: pellet

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings. However, the accompanying drawings are only examples for easily describing the content and scope of the technical idea of the present invention, and thus the technical scope of the present invention is not limited or changed. In addition, it will be apparent to those skilled in the art that various modifications and changes can be made within the scope of the present invention based on these examples.

1 is a block diagram showing a pellet forming process according to an embodiment of the present invention, Figures 2 to 6 is a schematic diagram showing a pellet forming process according to an embodiment of the present invention, Figure 7 is an embodiment of the present invention It is a top view which shows the shaping | molding die which concerns on this.

As shown, the pellet forming process according to the present invention is preceded by a step of preparing a dough by mixing a catalyst or a ceramic powder and a binder and kneading it.

In this step, the catalyst or ceramic is pulverized into a powder of fine powder by using a mixer and mixed with a binder.

Here, the binder is a polymer selected from the group consisting of methyl cellulose (MC), polyvinyl alcohol (PVA), ethylene vinyl acetate (EVA), carboxymethyl cellulose (CMC) mixed in distilled water at 40 ~ 100 ℃ To prepare a liquid phase. At this time, the mixed amount of the polymer and distilled water may be used by mixing 1 to 50 parts by weight of the polymer to 100 parts by weight of distilled water. When the polymer is mixed in an amount of 1 part by weight or less, the bonding force is lowered. When the mixture is mixed in an amount of 50 parts by weight or more, the mixing of the powder and the polymer is not performed well, and the polymer is agglomerated, so the powder is not uniformly distributed. It is preferable to mix in the range.

In addition, the dough by the mixing of the powder and the binder is prepared by mixing in the range of 50 to 150 parts by weight of the binder with respect to 100 parts by weight of the powder, the dough using a high-speed mixer or a screw extrusion type kneader or press type kneader It is preferable to mix uniformly.

The step of placing the prepared dough 40 in the upper part of the mold 10, the plurality of through-holes 11 are formed.

The mold 10 in this step is preferably made of a plate material of a metal material or a polymer material that is not deformed by pressurization in a plate shape. For example, typical metallic materials include stainless steel, steel, and aluminum. Such a mold is preferably formed in a plate shape having a top and a bottom formed in a plane so that pressurization of the press is evenly received and the through hole forming operation can be easily performed, rather than the top and bottom being curved.

In addition, the through hole 11 formed in the forming mold 10 may be formed in a cylindrical shape or may be variously formed in a polygonal shape or other shape by controlling the shape of the pellet 60 to be described later, and the inner surface of the through hole also in the axial direction. It is possible to increase the surface area by forming a large number of fine grooves in the molding frame thickness direction so that the inner surface of the through hole is formed by bending rather than a smooth surface.

In addition, the mold 10 may be formed to have a variety of thickness to take the length of the required pellet. For example, the tableting method can be formed to a thickness of less than 3mm that can not produce a high-strength pellets can be molded.

And the size of the mold can be provided in a variety of sizes within the range that the pressurization of the press can be evenly transmitted, the number of internal through-holes can be formed to be used in various numbers as needed.

Next, the step of pressurizing the dough 40 with the pressing table 30 by operating the press to be put into the through-hole 11 of the molding die 10 is performed.

The press uses a table 20, which is a general configuration, and a press table 30 positioned at an upper portion spaced apart from the upper surface of the table and pressurized downward. In addition to the above structure, It is possible to use a press of a structure that is fixed and pressurized while the lower table is raised. Here, the table and the pressure bar is formed in a plate shape of a polygon such as a circle or a square, detachably mounted from the press main body, the table or pressure bar is formed of a metallic material and is selected through the front surface without being deformed by the applied pressure. It is desirable to allow pressure to be delivered.

By operating the press configured as described above, when the pressure zone 30 is lowered, the dough is pressurized, and the pressurized dough 40 is introduced into the through hole 11 formed in the molding die 10. Here, the pressing force of the press is to press the dough 40 at a strong pressure in the range of 1kg ~ 100ton per unit area, the dough kneaded into the through-hole 11 also receives a strong pressure to form a tight gap between tissues to increase the strength do.

When the pressurization is completed, the press presser 30 is returned to its original position, and the step of removing the remaining dough material located outside the through-hole 11 of the molding die with the scraper 50 is performed. That is, by scraping the upper surface of the mold 10 with a scraper or other knife to remove the dough other than the dough filled in the through hole of the mold. The kneaded material removed here can be collected and reused to minimize the amount discarded during pellet manufacturing.

By drying the mold 10 from which the residual dough is removed, the dough of the mold through-hole 11 is separated from the mold by moisture evaporation, and a drying pellet receiving step is received in the form of pellets 60. The drying is carried out through a dryer, the drying conditions are made for 10 to 30 minutes at a temperature of 50 ~ 150 ℃. If the drying temperature is low, the time required for drying is increased, and if it is higher than the temperature, it is preferable to dry in the above range because cracks are generated due to rapid drying and the pellets are broken.

In the drying process, the dried dough (pellets) is naturally separated from the through-hole of the molding die due to the volume reduction due to moisture evaporation, and even those attached to some molds can be easily separated by hitting the molding die.

The dried pellets received by the drying are subjected to a calcination step in which a binder is removed by applying heat to prepare final pellets. The firing is made for 3 to 10 hours at a temperature of 500 ~ 800 ℃ to completely remove the binder.

Hereinafter, the present invention will be described through examples.

Example 1 Preparation of Pellet-shaped Ni-Al ₂ O ₃ Catalyst

First, the Ni-Al ₂ O ₃ catalyst (Ni content: 50% by weight) powder is stirred well with a binder and kneaded through a screw extruder.

The binder was prepared by mixing 5 g of methyl cellulose (Methyl cellulose: MC) as a polymer in 100 g of distilled water at 50 to 60 ^° C. Here, the mixture of distilled water and the polymer was used a high speed stirrer. Together with the foam, the polymer is evenly mixed with distilled water. After aging for about 10 hours, the foam almost disappears and a clear binder solution is produced.

In addition, the dough was prepared by mixing 22 g of binder with 20 g of powder.

The hole diameter of the catalyst mold is processed to about 2 mm.

The catalyst batter is evenly spread over the catalyst mold and then installed in the press apparatus.

Here, in order to prevent contamination of the press apparatus by the kneaded catalyst, a plate (table, press table) of a size equal to or larger than the size of the catalyst mold is installed up and down. The material is the same as the catalyst mold, and the thickness does not matter.

Pressure is applied to the press apparatus to allow the catalyst batter to fully enter the catalyst forming mold. At this time, the pressure is about 3 to 4 ton.

After about one minute, the pressure was released, and then the plate installed above and below the catalyst mold was removed, and the catalyst dough remaining on the catalyst mold was removed with a scraper.

The catalyst mold is dried for 20 minutes at about 100 ^° C. in a drying oven so that most of the catalyst is pelletized and separated from the catalyst mold.

Some undivided catalyst is separated by pressing with a needle or hitting the mold.

The received dried pellets were calcined for 6 hours in a kiln at 650 ^° C. to remove the contained binder components, and finally the pellets were received.

The strength of the catalyst prepared by this method is shown in Table 1 below. In Comparative Example 1, a catalyst in pellet form molded by tableting manufactured by Sud-chemie was used.

TABLE 1

As shown in Table 1, it can be seen that the catalyst strength of Example 1 is 8 times higher than that of Comparative Example 1 prepared by tableting. This is because the preparation of the catalyst by the tablet press does not sufficiently transfer the striking force, but the strength is lowered. In contrast, the first embodiment of the present invention is press-pressing, so that even if the mold is thin, sufficient pressure can be delivered to form a compact structure. Therefore, it can be seen that the production method of the present invention is more suitable than the tableting method when forming a short catalyst.

Claims

A press consisting of a table 20 and a press table 30 positioned at an upper part spaced apart from the table surface and pressurized downward by an operation, and a plurality of through holes 11 settled on the table of the press, In the method for molding the catalyst or ceramic pellets using the formed mold 10,

Mixing a catalyst or ceramic powder and a binder and kneading the same to prepare a dough;

Placing the prepared dough on an upper part of a mold formed with a plurality of through holes;

Operating the press to press the dough into a pressurized dough so that the dough is introduced into the through hole of the mold;

Returning the press presser to press to the original position, and removing the residual dough placed outside the through hole of the mold by a scraper;

A drying pellet receiving step of drying the molding mold from which the residual dough is removed, wherein the dough material of the through-hole of the molding mold is separated from the molding mold by moisture evaporation and received in pellet form;

And a baking step of removing the binder by applying heat to the dried pellets.
The method of claim 1,

The binder is selected from the group consisting of methyl cellulose (MC), polyvinyl alcohol (PVA), ethylene vinyl acetate resin (EVA), carboxymethyl cellulose (CMC) in 100 parts by weight of distilled water at 40 ~ 100 ℃ Pellet molding method characterized in that the polymer is prepared by mixing 1 to 50 parts by weight.
The method of claim 1,

The molding die is a pellet forming method, characterized in that made of a plate of metal or polymer material which is not deformed upon pressurization of the press.
The method of claim 1,

The pressing force of the press is pellet forming method, characterized in that made in the range of 1kg ~ 100ton per unit area.
The method of claim 1,

The drying is pellet molding method, characterized in that made for 10 to 30 minutes at a temperature of 50 ~ 150 ℃.
The method of claim 1,

The firing is pellet forming method, characterized in that for 3 to 10 hours at a temperature of 500 ~ 800 ℃.