EP1385614A2

EP1385614A2 - System for the production of granulates consisting of biopolymers and mineral raw materials

Info

Publication number: EP1385614A2
Application number: EP02737831A
Authority: EP
Inventors: Peter Kretschmer; Reinhard Schmidt
Original assignee: Romonta Ceralith GmbH
Current assignee: Romonta Ceralith GmbH
Priority date: 2001-05-10
Filing date: 2002-05-07
Publication date: 2004-02-04
Also published as: DE10122615A1; WO2002089968A3; WO2002089968A2

Abstract

The invention relates to a system for the production of granulates consisting of biopolymers and mineral raw materials. Said granulates are products which can be used in a large variety of ways i.e. as heat insulating materials, sound proofing materials, compensating insulating materials, for micro-air-conditioning in living areas, work areas, and as filling materials in furniture, furniture elements, packaging and similar. Said granulates can also be used as additives in light construction elements and other light building materials. They can also be used as adsorption agents in the purification of waste gas or waste water and can be used in a modified form as soil enhancers. The inventive system can be used to carry out a method for the production of extrudates made of biopolymer and mineral raw materials according to DE 43 21 627, EP 0 632 101 and US 5,498,384. The method is characterized in that the biopolymer raw materials and mineral additives are mixed with a waterproofing agent and are subsequently processed in an extruder. The inventive system essentially comprises storage areas and storage capacities for solid and liquid products which are to be used and the same for a manufactured product and the fine proportion of manufactured product thus produced, an extruder, a granulator, means of conveyance for the products which are used and those which are manufactured, in addition to an outgoing air/waste gas system, a tempering device for the extruder and other measuring, control and adjusting devices. The device is characterized by a combination of all system parts and the use of an endless paddle screw as a post-reaction area with an integrated fine grain sieve function and a connected waste gas system. All operations and units are process-controlled.

Description

description

Plant for the production of granules from biopolymer and mineral raw materials

The invention relates to a plant for producing granules from biopolymeric and mineral raw materials.

Said granules are extremely versatile products, which are suitable as thermal insulation, soundproofing, compensating insulation, for microclimatisation of living and working spaces in particular, and also as a filler in furniture, furnishing elements, packaging and the like. Furthermore, possible uses as an additive are seen, for example, in lightweight elements and other lightweight materials. They can also be used, for example, as adsorbents in exhaust gas or wastewater purification, as well as in modified form as valuable soil materials.

With the plant according to the invention, a process for the production of extrudates from biopolymer and mineral raw materials according to DE 43 21 627, EP 0632 101 and US 5,498,384 is to be implemented in terms of plant technology. The essential feature of this process is that biopolymer raw materials and mineral additives are mixed with a water repellent and then processed in an extruder.

In particular, cereals such as wheat, rye, maize, triticale, rice, barley and buckwheat, oilseed extraction meal such as rapeseed, cottonseed, soybean, sunflower and linseed extraction meal, animal wool, preferably sheep's wool, vegetable fibers, especially cotton, are suitable as biopolymer raw materials. Flax and flax, wood flour, Chinese reed, straw and dried grass are provided. Limestone powder, hydrated lime, Portland cement, marl, clay powder, perlite, diatomaceous earth, glass and plaster are preferred mineral raw materials. Sodium and potassium water glass, silica gel, sodium aluminate and organic acids, in particular acetic acid, are provided as water repellents. The hydrophobizing agent or agents are added at a suitable point in the process sequence, ie before and / or during the extrusion. With regard to the specific product composition, reference is made to the specified information in the patent literature mentioned.

With regard to the implementation of the process, the apparatus must first be based on a mixing process with subsequent extrusion.

Both processes are both procedural and plant-side in the patent and other

Technical literature as well as extensively described in relevant reference works.

However, a practical system concept could not be used for the production of extrudates in granular form from biopolymer and mineral raw materials.

To develop such is therefore the object of the invention.

On the plant to be proposed according to the invention, granules of different

Composition can be produced. The granules should be as dust-free as possible

To be available.

The object was achieved according to the features of main claim 1.

Appropriate configurations are specified in the subclaims.

The main material components for a granulated end product produced in the extrusion process with the possible uses described at the beginning are, on the one hand, vegetable raw materials, for example fine rye meal, fine rye bran, and

Other mineral additives, preferably white lime hydrate and water glass, plus

Water.

Depending on the intended use and the parameters of the end product to be set, other biopolymeric, mineral or hydrophobic substances can be added or used alternatively.

The manufacturing process itself is described in DE 43 21 627, EP 0 632 101 and US 5,498,384. According to the invention, this is implemented in terms of plant technology as described below. The main components of a system complex with which granules of the type in question can be produced are:

- storage areas for solid and liquid feed products,

- conveyor systems for solid feed products, - feed pumps for liquid feed products,

- dosing devices for solid and liquid feed products,

Extruders, preferably twin-screw extruders,

- granulator,

- paddle screw with facilities for screening fine grain and as a post-reaction space for strengthening and surface treatment,

- conveyor systems for the removal of the finished product,

- storage area for the finished product,

- assembly line,

- Exhaust air / exhaust gas cleaning system, - Means for the removal and further processing of the fine grain,

- electrical switchgear,

- Process control system.

In addition, the following system areas should be provided: - Direct connection for water,

- intermediate storage for solid and liquid feed products,

- Bulk density measurement.

The various biopolymer and mineral components are available as silo goods, provided they are solid components.

Liquid components are stored frost-free in suitable tanks. The solid components as well as the liquid components are fed via conveying devices, for example screw conveyors for solids and constant feed pumps for liquids and suspensions, if necessary using additional interim storage facilities, correspondingly assigned metering devices, the arrangement of intermediate containers directly above the individual metering devices making sense. Differential dosing scales can advantageously be used for dosing the solid components. The liquid components are dosed, for example, by frequency-controlled dosing pumps. It is dosed directly into the extruder.

In the extruder, the individual components are mixed intensively and with the addition of heat from the outside. With regard to a constant end product quality, it is important that the individual components are added in defined, reproducible ratios to one another and as a function of the extruder screw speed at appropriate temperature conditions.

The feed materials are mixed intensively by means of the extruder screws, transported in the direction of the tool, which is designed as a perforated plate, and pressed through it. When exiting the perforated plate, the extruded strands pass a granulator, which is designed, for example, as a rotating knife. The strands are cut into individual granules and transported to a downstream paddle screw. For this purpose, the forces released during cutting are advantageously used.

The granulate is transported further inside the paddle screw and cools down in the process. Post-reactions to form amylo-aminobiological complexes also take place here. At the same time, fine particles that have formed due to abrasion or during the cutting process are separated by means of an integrated sieve.

The paddle screw is dust-tight and arranged in an inclined position in an increasing direction in the conveying direction. A spur gear motor is provided as the drive. Other types of drives are possible.

The granulate is fed from the extruder in the lower area.

Control openings can be provided at a suitable point. In the bottom of the paddle screw in front of the granulate outlet there is an interchangeable sieve for screening off the fine fraction from the granulate. The mesh size depends on the grain spectrum of the granulate.

The removal of the fine fraction takes place via a trough screw conveyor located directly under the paddle screw or another suitable conveying device. After leaving the paddle screw, the granulate is fed to a finished product silo by means of suitable conveying devices and can be removed from it for assembly.

During the extrusion, a water vapor-gas mixture is created as a by-product. The gas-tight design of the extruder and the constant suction of the vapor from the paddle screw ensure that the water vapor / gas mixture does not escape into the room air. It flows at a temperature of approx. 100 ° C and approximately atmospheric pressure together with the granulate into the paddle screw below. In the area of the sieve bottom of the paddle screw, the slightly cooled water vapor / gas mixture, which has been completely absorbed by the ambient air, is mixed with the ambient air that has been sucked in, thereby further cooling. This now saturated air-gas mixture is cleaned of entrained dust particles in an air filter. The cleaned air-gas mixture is then cooled below the dew point. The condensed water can thus be removed via a siphon.

The air-gas mixture, which is still saturated, is heated by a reheater. It flows outside via an adsorber.

All processes and units are electronically monitored and operated and controlled by an electrical switchgear. For this purpose, the electrical switchgear consists of the low-voltage system, the control system, the process control system, an uninterruptible power supply and the corresponding cabling. Using the example of a system for producing insulating material granules for blowing or pouring into cavities in roofs, ceilings and walls and the like, consisting of solid and liquid insert components or suspensions, the invention is explained in more detail with the aid of a flow diagram. The feedstocks are biopolymeric, mineral and hydrophobic components, plus water.

The reference symbols used in the flow diagram have the following meaning:

1 bulk silo for a biopolymer solid component, 2 bulk silo for a further biopolymer solid component,

3 bulk material silo for a mineral solid component,

4 tank for a hydrophobic liquid component,

5 tank for a biopolymer liquid component,

6 water connection, 7 conveyor system for the biopolymer solid component from the bulk goods silo 1,

8 conveyor system for the biopolymer solid component from the bulk goods silo 2,

9 conveyor system for the mineral solid component from the bulk material silo 3, 10 intermediate container for the biopolymer solid component from the

Bulk material silo 1, 11 intermediate container for the biopolymer solid component from the bulk material silo 2,

12 intermediate containers for the mineral solid component from the bulk material silo 3,

13 dosing scales for the biopolymer solid component from the bulk silo 1, 14 dosing scales for the biopolymer solid component from the bulk silo 2,

15 dosing scales for the mineral solid component from the bulk material silo 3,

16 intermediate containers with dosing pump for the hydrophobic liquid component,

17 intermediate container with dosing pump for the biopolymer liquid component, 8 intermediate container with dosing pump for water, 19 extruders, twin-screw extruder, 0 granulator, 1 paddle screw, 22 trough screw conveyor,

23 conveyor system for finished product,

24 silo for finished product,

25 Exhaust / exhaust system.

The solid components are stored in bulk silos 1, 2 and 3. Tankers take care of the delivery. The bulk goods silos 1, 2 and 3 are filled from these by means of compressed air conveyance via blow-in pipes. Due to the fact that the solid components tend to form mixtures that are at risk of dust explosion during loading, the bulk goods silos 1, 2 and 3 are designed to be pressure shock-proof and explosion-proof.

Assigned conveyor systems 7 and 8 are each loaded with a biopolymeric solid component via cellular wheel locks. The conveyor system 9 is fed directly from the bulk material silo 3 with a mineral solid component without the interposition of a cellular wheel sluice. The conveyor systems 7, 8 and 9 mentioned are spiral conveyors. Depending on the local conditions, the conveyor path can be bridged by connecting several conveyors in series. In the example, two spiral conveyors with different inclinations are arranged one after the other. The conveyor systems 7, 8 and 9 transport the solid components into intermediate containers 10, 11 and 12, which are located directly above dosing scales 13, 14 and 15.

The intermediate containers 10, 11 and 12 are PVC-coated and provided with an antistatic polyester fabric. The discharge takes place via fulling floors. The dosing scale 15 for the mineral solid component from the bulk material silo 3 is provided with an agitator. The dosing scales 13, 14 and 15 are differential dosing scales with a 3-point weighing system. The bulk material is in each case discharged from it by means of a horizontally arranged screw with an infinitely variable speed and fed to the twin-screw extruder 19.

The material flows of the solid components from the bulk goods silos 1, 2 and 3 to the twin-screw extruder 19 are each carried out separately in parallel. The hydrophobic liquid component is in a tank 4, the biopolymers

Liquid component stored in a tank 5. A water connection 6 is also available

Available.

For the liquid components and water, intermediate containers 16, 17 and 18 are provided in each case, which by means of feed pumps or by the pressure in the

Drinking water network can be filled.

The required amount of liquid is obtained from the respective by means of dosing pumps

Intermediate container 16, 17 and 18 suctioned off and fed to the twin-screw extrader 19. All of the feed materials mentioned are added in defined recipe ratios depending on the extruder screw speed and the others

Process conditions.

The screws of the twin-screw extruder 19 rotate in the same direction.

This ensures good mixing of the insert components. The twin-screw extrader 19 is designed so that the process engineering

Sub-tasks such as drawing in, mixing, kneading, shearing and conveying can be optimally implemented. For this purpose, the screw geometry is adapted to the process engineering requirements. The screws advantageously consist of shaft shafts with exchangeable screw bushes. In the twin-screw extrader 19 with main drive, gearbox, temperature control unit for several

Temperature zones and the tool heating are warmed up by the external components (cylinder heating), mixed intensively by means of the screws, transported in the direction of the tool and finally pressed through the perforated plate. This is followed by a granulator 20 in which the strands emerging from the tool are cut into granules by rotating knives. The knife drive is a frequency-controlled AC motor with a control range of 1:20.

Using the tangential forces that occur during the pelletizing process, the pellets are fed directly to the loading area of a paddle screw 21. The paddle screw 21 is for reactions to form mechanical / chemical

Properties of the granulate required. It is still for the removal and the

Cooling of the granules as well as for the separation of fine grain, which has formed through abrasion or during the cutting process, is necessary. The paddle screw 21 is dust-proof and is made by one

Helical gear motor driven. The speed is infinitely adjustable. In the example, the installation position of the paddle screw 21 rises 15 ° in the conveying direction. It has two covered control flaps.

In the bottom of the paddle screw 21 there is advantageously an interchangeable sieve for sieving the fine grain out of the granulate over a length of approximately 2000 mm in front of the granulate outlet.

The mesh size of the sieve depends on the grain spectrum of the granulate. In the example this is <2 mm

To remove the fine grain, a foldable trough conveyor screw 22 is arranged directly under the paddle screw 21. The granulate is fed to a silo 24 via a conveyor system 23.

A finishing area follows.

The water vapor-gas mixture created during the extrusion is

Exhaust system 25 treated. This separates it in the area of the sieve plate

Paddle screw 21 slightly cooled now saturated air-gas mixture in an air filter of entrained dust particles. The cleaned air-gas mixture is then cooled below the dew point. The condensed water is discharged through a siphon.

The air / gas mixture, which is still saturated, is heated by a reheater, and the relative humidity drops. It then flows outside via an adsorber.

Suitable measuring, control and regulating devices are also provided, which are designed in a manner customary in the art.

Claims

Plant for the production of granules from biopolymer and mineral raw materials

1.System for the production of granules from biopolymer and mineral raw materials, consisting of storage areas and storage capacities for solid and liquid feed components as well as for the finished product and resulting fine parts of the finished product, an extruder, a granulator, conveying agents for feed and finished products as well as dosing devices for solid and Liquid insert components, further consisting of an exhaust system, a temperature control device for the extruder and measuring, control and regulating devices, characterized in that the above-mentioned parts of the system also have a post-reaction chamber for the formation of mechanical / chemical properties of the granules in the form of a paddle screw (21) integrated fine coma screening and connected exhaust / exhaust system (25) are added, resulting in the following flow diagram:

- storage of the biopolymer and mineral solid components,

Storage or provision of the biopolymeric and other liquid components, metering and supplying of all solid and liquid components to the extruder (19) with the interposition of suitable conveying systems and devices, if appropriate with integration of additional storage options,

Processing of the metered-in insert components in the extrader (19) to form the finished product in the form of a strand, - pelletizing the strands in the downstream granulator (20) to form the granulate from the finished product and feeding the same to the paddle screw (21),

- After-reactions of the granulate to form amylo-aminobiological complexes, transport and cooling of the finished product with simultaneous separation of the fine grain from the granulate within the paddle screw (21) with separate discharge, - Storage and packaging of the granulate.

2. Plant for the production of granules from biopolymer and mineral raw materials according to spoke 1, characterized in that a plant for the production of insulation granules for blowing or pouring into cavities of roofs, ceilings and walls and the like, consisting of solid and liquid insert components or Suspensions, constructed as follows:

- Storage of a biopolymer solid component in a bulk material silo (1);

- Storage of a second biopolymer solid component in a bulk silo (2);

- Storage of a mineral solid component in a bulk silo (3);

- Storage of a hydrophobic liquid component in a tank (4); - Storage of a biopolymer liquid component in a tank (5);

- water connection (6);

- Loading a conveyor system (7) with the biopolymer solid component from the bulk material silo (1) or a conveyor system (8) with the second biopolymer solid component from the bulk material silo (2) in each case by means of cellular wheel locks; - Loading a conveyor system (9) with the mineral solid component from the bulk material silo (3) without the interposition of a cellular wheel sluice;

Transport of the solid components by means of the conveyor systems (7, 8 and 9) into correspondingly assigned intermediate containers (10, 11 or 12), which are equipped with dosing scales (13, 14 or 15), preferably designed as differential dosing scales with a 3-point weighing system, are coupled, the bulk material being discharged directly from them by means of horizontally arranged screws with an infinitely variable speed and being able to be metered into the downstream twin-screw extrader (19);

- Transport of the hydrophobic and biopolymeric liquid components by means of feed pumps and water by means of the existing pressure in the drinking water network into correspondingly assigned intermediate containers (16, 17 and 18), which are provided with metering pumps, whereby the liquid components can be added to the twin-screw extrader (19);

- Extrusion of all insert components in the twin-screw extrader (19), which essentially consists of the main drive, gear, co-rotating screws, cylinder and tool heating with temperature control unit for several temperature zones and the tool, the latter designed as a perforated plate; - Subsequent pelletizing of the strands of finished product leaving the perforated plate in a pelletizer (20), which is advantageously formed by rotating knives with frequency-controlled AC drive in the control range of 1:20, and transfer of the pellets using the tangential forces generated during cutting directly into the Loading area of a paddle screw (21);

- Transport of the granules with simultaneous post-reaction to form amylo-aminobiological complexes, as well as cooling and sieving of the fine grain from the granules within the paddle screw (21);

- Removal of the fine grain by means of a foldable trough conveyor screw (22) arranged directly under the paddle screw (21);

- Transporting the granules cleaned of fine particles by means of a conveyor system (23) to a silo (24);

- Subsequent assembly if necessary.

3. Plant for the production of granules from biopolymeric and mineral raw materials according to claim 2, characterized in that the paddle screw (21) is dust-tight, has covered control flaps, driven by a helical geared motor with a continuously adjustable speed and increasing in the conveying direction, preferably with a gradient of approx. 15 °, it is installed that means for receiving the granules from the twin-screw extrader (19) are arranged in the lower area, that in the bottom of the paddle screw (21) there is an interchangeable sieve with a mesh size defined as a function of the grain spectrum of the granules, for example <2 mm, for sifting off the fine fraction from the granulate, advantageously over a length of approx. 2000 mm before the discharge, and that the paddle screw (21) in the higher area provides suction for the water vapor gas produced during the extraction Mixture.

4. Plant for the production of granules from biopolymer and mineral raw materials according to claims 2 and 3, characterized in that an exhaust air / exhaust system (25) for treating the water vapor / gas mixture is connected to the suction of the paddle screw (21).

5. Plant for the production of granules from biopolymer and mineral raw materials according to claims 1 and 2, respectively, characterized in that the intermediate containers (10, 11 and 12) are coated with PVC and provided with an antistatic polyester fabric, which the pourable insert components in each case can be discharged by means of mill floors and that the dosing scale (15) has an agitator for the mineral solid component from the bulk material silo (3).

6. Plant for the production of granules from biopolymer and mineral raw materials according to claims 1 and 2, respectively, characterized in that the conveyor systems (7, 8 and 9) are spiral conveyors, these depending on the local conditions by connecting several conveyors in series if necessary can be formed with different inclinations.

Here is a page drawing!