GB2086420A

GB2086420A - Briquetting coal by vibration without use of binders

Info

Publication number: GB2086420A
Application number: GB8131944A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-10-28
Filing date: 1981-10-22
Publication date: 1982-05-12
Also published as: NL8104887A; IE52573B1; WO1982001562A1; FR2492839A1; PL233605A1; GB2086420B; IE812481L; LU83721A1

Abstract

The Fuel briquette comprises up to 100% coal in particle and/or powder form compressed or compacted by vibration. By the production of the briquette coal in particle and/or powder form possibly mixed up with another material is poured into a mould cavity and the content thereof is vibrated to compaction and the fuel briquettes thereby Formed in the mould cavity are removed from the mould cavity. The apparatus comprises at least one mould cavity, a vibration means for the vibration of the walls thereof, means for filling the mould cavity with briquette material and means for removing the compressed or compacted content from the mould cavity. Thereby durable briquettes can be produced simply and at low costs without a binding agent being necessary. Furthermore apparatuses can be used being known for the production of concrete stones, tiles and sand mouldings.

Description

SPECIFICATION A fuel briquette and a method and an apparatus for manufacturing such briquettes The invention relates to a fuel briquette and a method and an apparatus for manufacturing such briquettes.

The fuel briquette according to the invention is characterized in that it comprises up to 100% coal in particle and/or powder form compacted or compressed by vibration. It appeared that said fuel briquette comprising 100% coal in particle and/or powder form compacted by vibration has adequate strength to resist stress occurring during transportation and handling from place of origin to the place of utility. Thereby coal in particle and/or powder form may be provided a higher value and a larger field of application that at present is the case for coal dust, screenings and slack.

Furthermore it appeared that such briquettes are also able to maintain a fair cohesive force although they contain other materials even without a binding agent which probably is due to the fact that coal in particle form per se during and after vibration acts as a binding agent.

Moreover the fuel briquette may be characterized by the means stated in claims 2, 3 and/or 4, whereby the fuel briquette may be provided with an increased cohesive force, larger heating value, durability and/or ease of inflammability, the materials other than coal which perhaps could not be used otherwise may serve to further reduction of the price or to the inprovement of the fuel briquette.

Screened coal such as coal dust or minor coal particles has at present a rather low market price as also is the case for several types of combustible refuse or waste whereby briquettes may be manufactured simply and at low costs.

In case of calcium chloride forming part of the briquette said material acts as an accelerator e.g.

if cement, lime or calcium oxide or fly ash also form part of the briquette, and where hydroxyethylcellulose or sodiumcarboxymethylcellulose form part of the briquette these substances act as thickening agents, while substances such as stearin and paraffin increase the strength and combustibility of the briquette. In cases where cement in a manner known per se forms part of the briquette the content of the cement is 1-8% by weight, preferably 6% by weight, whereby a satisfactory strength of the briquette is obtained, so that the briquettes are able to resist the effects imparted on them during storing and handling.

In cases where the briquette contains hydroxyethylcellulose the content of this is 0-0.05 %o by weight, preferably 0.03 %o of weight (weight per thousand), and in excess of acting as a thickening agent the cellulose also acts as a means for promoting of a perfect combustion of the inflammable components of the briquette especially by briquettes of a high humidity.

In cases where the briquettes contain calciumchloride the amount thereof is 1-3% by weight, preferably 2.5 %0 by weight of the briquettes.

In cases where the briquettes contain lime, calcium oxide and/or fly ash or fly dust these substances contribute in neutralizing the effects of the sulfur in the surroundings being subject to the flue gases of the briquettes having coal particles of a high sulfur content.

Some of the substances mentioned also contribute to an increased production rate of the briquettes. This is the case by several of the substances stated in claims 3 and 4.

The method according to the invention is characterized by the means stated in claim 7.

Thereby a method hitherto unknown for the manufacturing of the fuel briquettes is obtained, whereby coal dust or minor coal particles may be subjected to an ennobling or refinement and may achieve a higher value and a larger field of application at relatively low costs and in a simple manner. Hitherto it has not been realized that coal dust or small coal particles per se form a binding agent when vibrated only and which can provide an adequate cohesive force to the briquettes manufactured so that these can resist stress occurring during transportation and handling.

By the means stated in claim 8 a method is defined whereby high quality briquettes are guaranteed.

By the means stated in claim 9 an increase of utility of the method is obtained so that the method is not limited to a batchwise production of briquettes but may also take place by a continuous production thereof.

The invention also relates to an apparatus for production of fuel briquettes by the method, said apparatus being characterized by the means stated in claim 10. Thereby a hitherto unknown apparatus for the production of fuel briquettes comprising only coal dust or small coal particles is achieved, and, as will appear from claim 11, 12 and 13, the apparatus may comprise machines known per se being hitherto used or intended for other purposes than the production of fuel briqettes of the invention.

Examples of such apparatuses are casting machines for the concrete or brick making industry where the materials for casting hitherto used are replaced by coal dust possibly mixed up with suitable amounts of other materials.

In the iron industry as well machines are existing which may be used for the production of the briquettes such as machines for producing cores by vibration for casting moulds for iron or metal, or for the production of casting moulds for iron or metal per se where the cavities of the forming surfaces of the machines are complementary to the shapes of the fuel briquettes intended to be produced thereby. Thereby the briquettes may be provided with different shapes, with plane side faces as well as with rough side faces for increasing the burning surface of the briquettes during combustion.

The apparatus for production of the briquettes may also be a moulding machine of the kind manufactured by Dansk Industrisyndikat A/S, Copenhagen, a so-called DISAMATIC (iD moulding machine, said machine produces casting moulds with vertical joint surfaces, the modification of this machine for the production of briquettes according to the invention having a mould board with cavities being formed complementary to the shape of the fuel briquettes intended to be produced thereby, so that instead of providing casting moulds it produces fuel briquettes. Instead of using conventional moulding sand for the production of the casting moulds coal dust with or without minor coal particles is mainly used.

In a common machine for production of concrete slabs e.g. 50 m3 of fuel briquettes corresponding to a production of 100 ton may be moulded a day.

The fuel briquettes may also be produced by a continuous moulding in a shaking conveyor or by extrusion of the material to be moulded through a possibly vibrated moulding or forming tube or by vibration of an extruder spindle or an extruder plunger. In case the briquettes are produced continuously a cutting off device may be mounted in extension of the apparatus for the cutting off of the rod shaped material into briquettes.

In the following text and example of the use of an apparatus according to the invention for the manufacture of the briquettes is explained which apparatus originally was intended for production of concrete slabs.

1. Materials forming parts of the briquettes are weighed out and mixed together in a mixer or mixing machine.

2. Via a conveyor the mixed materials are taken to a silo in a concrete stone moulding machine.

3.The mixed materials are delivered to a mould filling carriage from the silo.

4. The mould filling carriage is displaced from the silo to the top of the mould and the materials are dropped in the mould cavities. The mould filling carriage is reciprocately displaced on top of the mould and simultaneously the materials in the mould cavities are vibrated by a vibrator, positioned below the mould. When the mould cavities are completely filled the mould filling carriage is returned to its initial position.

5. Piston plates above the mould cavities are lowered to abutment against the mould, the vibrators are activated again and are in function a predetermined number of seconds.

6. A steel plate forming the basis of the mould with the mould cavities is withdrawn and the mould and the briquette material in the mould are then supported by a wooden plate.

7. The mould is raised and at the same time the piston plates are maintained immovable relatively to the wooden plate whereby the briquettes are pressed downward out of the mould cavities and are thereby separated from the mould. During this operation the vibrators on the piston plates for removing of castings i.e. the briquettes are in function.

8. The wooden plate carrying the briquettes is removed and a next wooden plate together with the steel plate are displaced to their position below the mould.

9. The mould is lowered into abutment against the steel plate and simultaneously the piston plates are raised from the mould. Then the mould with its mould cavities is ready to be refilled with briquette material. Point 4-9 may be repeated.

10. Wooden plates carrying the briquettes are conveyed from the apparatus to a storing location.

1 After a predetermined storage time e.g. 24 hours the briquettes are removed from the wooden plates and are piled on carrying pallets.

Claims

1. A fuel briquette characterized in that it comprises up to 100% coal in particle and/or powder form compacted or compressed by vibration.

2. Briquette according to claim 1, characterized in that it also contains material chosen from the group: ground plastic waste, oil waste, ground and dried refuse or waste, epoxy adhesives, wooden chips, inflammable dust or particles of materials such as wood, peat and lignite.

3. Briquette according to claim 1 or 2, characterized in that it contains other materials chosen from the group: urea adhesive no. 1351 from Kemicasco, lye of sulphite (Wafolin), solid alcohol in particle form and alphatic (fatty) hydrocarbons in a liquid, particles or pastelike form.

4. Briquette according to claim 1, 2 or 3 characterized in that it also contains other materials chosen from the group: stearin, paraffin, hydroxyethylcellulose, sodiumcarboxymethylcellulose, lime or calcium oxide, fly ash and calcium chloride (CaCI2).

5. Briquette according to claim 1 2,3 or4, in which cement forms a part thereof, characterized in that the cement makes 1-8%, preferably 6% by weight thereof.

6. Briquette according to claim 1, 2, 3,4 or 5, characterized in that where it contains hydroxyethylcellulose this material makes at most 0.05 %o, preferably 0.03 %o by weight thereof, and that a possible content of calcium chloride makes 1-3 %o, preferably 2.5 %o by weight thereof

7.Method for production of fuel briquettes from coal, characterized in that coal in particle and/or powder form possibly mixed up with another powder or particle formed, liquid or pastelike preferably inflammable material is poured into a mould cavity and that the content of the mould cavity comprising up to 100% coal dust with or without coal particles is vibrated into compacted or compressed state and that the fuel briquette thereby formed in the mould cavity is removed from the mould cavity.

8. Method according to claim 7, characterized in -that the content of the mould cavity is vibrated by a constant frequency of vibration for a predetermined period of time, in which possibly also pressing occurs, before the content is removed from the mould cavity, and that the content compressed and removed from the mould cavity is stored preferably supported in a single layer for a predetermined period of time.

9. Method according to claim 7 or 8, characterized in that the vibration, the possible pressing and the removal is made discontinuously or continuously.

10. Apparatus for production of fuel briquettes by the method according to claim 7, characterized in that it comprises at least one mould cavity, a vibration means for the vibration of the walls of the mould cavity, means for filling of the mould cavity with briquette material and means for removal of the content of the mould cavity.

11. Apparatus according to claim 10, characterized in that it is a machine of the kind otherwise being used for the production of slabs or bricks of concrete or tile, or of the kind otherwise being used for producing cores by vibration for casting moulds for steel or metal or for production by vibration of casting moulds for steel or metal where the cavities of the mould board are shaped complementary to the shape of the briquettes intended to be produced thereby.

12. Apparatus according to claim 10 or 11, characterized in that it is formed as a formdry mould production machine for moulds with vertical mould joint surfaces, where the mould board is provided with cavities being complementary to the shape of the fuel briquettes intended to be produced thereby.

13. Apparatus according to claim 10, characterized in that it is an extruder with at least one vibratable part such as an extrusion spindle or an extrusion plunger and that a cutting off device is provided for the separation of the rod shaped extrusion product into fuel briquettes.