JP2003515452A - Compression molding equipment for bulky items - Google Patents

Abstract

(57) Abstract The present invention relates to a compression molding apparatus for bulky materials. It is an object of the present invention to produce a highly homogeneous scab. For this purpose, bulky material is fed via a feed screw 5 to a roller press (4). The roller press (4) is fed with bulky material of different properties from two shafts (7, 9) arranged in series. The feed screw (5) is unsuitable for the process and is formed on the downstream side of the roller press (4), the shaft (9) on the upstream side in the transport direction to be partially filled with granules. From the downstream side in the transport direction.

Description

Detailed Description of the Invention

The present invention comprises a roller press, a supply hopper as a supply device for bulk goods, which is mounted on the upper side, and a screw conveyor arranged upstream from the roller press. A compression device for items with

[0002] Crude produc supplied as a powder, granulate or a mixture thereof.
t) is sometimes not suitable for further processes such as tabletting in the pharmaceutical industry. This is because the raw product has a very high proportion of air and / or is not sufficiently fluid. Compression molding of the green products prior to further processing and subsequent granulation thereof has been described in patents (DE 3431865 (Ge)).
It is known in rman Patent 3431865 C2)) but is not particularly practical. For example, a roller press with a screw conveyor for compression molding is installed before use. Using a screw conveyor, the raw product is fed from the feed hopper into the roller gap under a certain pressure.

Since the roller press is sealed on both sides and the conveyor is hermetically connected to the gap of the rollers, the air expelled from the raw product during compression passes through the raw material in the screw housing and into the raw material. It must move opposite to the carrying direction. The air may subsequently flow out through a feed column located in the feed hopper, which feed column becomes a resistance to the air as a function of height and density. However, some of the air also passes "explosively" through the gaps of the rollers, which causes the roller press to operate under load and generate nozzles.

In compression molding, it is desirable that the flakes formed during compression molding be as homogeneous as possible. This property has a direct impact on the final product. If the raw product in the feed hopper is not evenly distributed with respect to grain size or other properties, heterogeneous flakes will occur. This occurs especially when a portion of the compression molded raw material that does not have the desired grain size after granulation is recirculated to the feed hopper. Direct recycling of this compression molded raw material is not without problems. This is because the bulk specific gravity of this compression molded raw product is very different from the bulk specific gravity of the untreated raw product.

An untreated raw product with a bulk specific gravity of 200 g / l may have a bulk specific gravity of 800 g / l as a recycled feedstock after compression molding. This causes large fluctuations in the mass flow rate of the recycled product. In soft flakes, the proportion of the mass flow rate of the recycled product fed to the roller press is large, which has a positive effect on the homogeneous quality of the flakes, but the mass flow rate of the recycled material is Will result in being lost. Therefore, stabilization of flake quality is provided by a slow process only.

For this reason, to date, the mass flow rate of the recycled material has gone through a corrective mixing process with the raw product before it is compression molded.

The object of the present invention is to provide an apparatus for compression-molding granulated and granulated products, which apparatus produces a compression-molded product as homogeneous as possible. To do.

This object has been achieved by the compression-molding device described below according to the invention. In a compression molding device: The feed hopper has at least two shafts located one behind the other in the conveying direction of the screw conveyor, from which the screw conveyor is fed with bulky items of various types. In addition, it is supplied from the lower part to the shaft of the latter stage in the conveying direction; a granulating device having a granulating material separating device is connected to the downstream side of the roller press, and the granulating material is separated by a grain size. Yes; recirculation of the granules, which is not suitable for the next process, is being carried out from the separator in the conveying direction to the prestage shaft.

By using the compression molding apparatus in the present invention, a homogeneous flake quality is guaranteed throughout the manufacturing process. For this purpose, raw products and further constituent materials are initially fed parallel to the screw conveyor from various shafts. This makes it possible to feed only part of the constituent material to the screw conveyor from the preceding shaft (s) in the conveying direction, while allowing the raw product to be loaded from the latter shaft into the screw conveyor. ing. The optimum mixing of the raw materials to be compression-molded by the feeding of the respective raw materials, which comprises the granulate recirculated by the separating device, in the conveying direction of the screw conveyor, and the multi-thread screw conveyor acting as a mixer. It is brought about by the cooperation of. With respect to degassing, the following are preferred, as the expelled air does not have to pass through the generally full feed column in the rear shaft, but rather in either of the upstream shafts. Only a small, generally empty, raw material column needs to be passed through.

The proportion of feedstock that is unsuitable for the next process and has to be recycled is generally small, and the feed hopper shaft containing this feedstock is only partially filled anyway. So it is possible to degas through this shaft without great resistance.

Preferably, the upstream first shaft is fed with granules having larger grains. By "larger grain" is meant a larger grain compared to the raw product. It has been found that this material is suitable for screw cleaning and also serves as a feed aid in roller presses. The present invention will be described in detail below with reference to the drawings.

The compression molding apparatus includes a raw product compression molding portion 1, a granulation portion 2, and a granule separation portion 3.

The first part 1 comprises a roller press 4 having a horizontal material supply device. The material to be compression-molded is supplied under pressure to the roller gap of the roller press 4 via a screw conveyor 5, which screw conveyor 5 mixes the supplied material with a screw housing 5a and a multiple thread 5b. And have. The screw conveyor 5 is hermetically connected to the roller gap.

The roller press 4 is laterally sealed by a cover plate 6. A supply hopper for the granulated / granulated product, which is divided into a front shaft 7 and a rear shaft 9, is arranged above the screw conveyor 5. The rotor 8 is mounted inside the shaft 7 in order to move the raw product so as not to stay in the shaft 7.

The granulated raw product is introduced into the shaft 7. The screw conveyor 5 is feeding the green product under pressure into the roller gap of the roller press 4,
There, the raw product is compression molded into flakes S. The flakes S are subsequently granulated in part 2 of the device. Since the granulated product G is usually a wide granular pallet, it is not suitable for the subsequent processes. Therefore, in a continuous part 3 of the device, the granular pallet is separated into a granulate G1 suitable for the subsequent process and a granulate G2 which is recycled to the shaft 9 of the feed hopper. Granulated product G
Due to the low mass flow rate of 2, the screw conveyor 5 is only partially supplied with it. The balance of the feed is raw material in shaft 7. Thus, even in the early stages of the production process, the screw conveyor is fed from both shafts 7, 9 in parallel with material of different properties. This has a positive effect on the desired homogeneous flake quality.

[Brief description of drawings]

[Figure 1]   FIG. 1 is a partial schematic view of a compression molding device.

[Procedure for Amendment] Submission for translation of Article 34 Amendment of Patent Cooperation Treaty

[Submission date] September 15, 2001 (2001.15)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Contents of correction]

For this reason, to date, the mass flow rate of the recycled material has gone through a corrective mixing process with the raw product before it is compression molded. Further, a known compression molding apparatus of the items with a bulk (DE 3806398A1 (German Patent Application 3806398A1)) , the supply hopper has two shafts is not disposed above the roller press Te, goods bulky various types from the shaft to the roller gap may be fed in parallel to test. The proportion of bulky items of different types fed from different shafts into the roller gap may be adjusted by the metering element. The bulky articles that have passed through the roller gap are crushed and partially agglomerated or compressed into flakes . Are generally flakes, is ground up in a ball mill for final processing, are supplied to the mobile device to al, a fine particle product inferior production products of its quality, the shaft has a supply device for fine products Is recycled. Degassing of items bulky is via a feed column in the shaft for items with a bulk of raw products.

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Claims (3)

[Claims] 1. A screw conveyor comprising a roller press (4) and a supply hopper (7, 9) arranged upstream of the roller press (4) and serving as a supply device for bulky articles. (5) with a compression molding apparatus for bulky articles comprising: at least two feed hoppers (7, 9) arranged one behind the other in the conveying direction of the screw conveyor (5). Has two shafts (7, 9) from which the screw conveyor (5) is fed with bulky items of various types and is downstream in the conveying direction (7). A granulator (2) having a granulator (G) separator (3) is connected to the downstream side of the roller press (4), Cleans things (G) That the granules (G2) that are not suitable for the next process are recirculated from the separating device (3) to the preceding shaft (9) in the conveying direction. And compression molding equipment. 2. A compression molding device according to claim 1, characterized in that the screw conveyor (5) is a multi-thread screw for mixing bulky items. 3. The compression molding device according to claim 1, wherein the first shaft (9) in the carrying direction is supplied with granules (G) having larger grains.