Generally, there is no need of a binder for compaction-granulation of powders and the bonding of particles is ensured by the mechanical pressure exerted on the product being compacted. The compacts produced at low or high pressure are in flake form of variable thickness (up to 30 mm).
According to the material and the end-product required, the main stages of the process can be as follows :
A preparation unit for powders (screening-crushing, drying, sieving) A weighing and mixing unit of the components
A compaction unit transforming the powders into flakes
A granulation-screening unit converting the flakes into granules of the required size
And for some plants and in particular for the production of compacted fertilizers, a finishing unit with polishing and coating of granules for improved appearance, reduced amount of residual fines and easier storage
The capacity of a compaction-granulation line can range from 50 kg/h to 50 T/h of granules and for products up to 200° C or even more.
Briquetting (agglomerates, briquettes, compacts, ... ), and compaction-granulation (granules) processes are technologies of particle size enlargment using a dry process in which dusts or powders are formed into shapes.
A technical solution
- Obtain products of the same size, volume and weight: an agglomerate/a compact can represent the exact dose required in a process - Obtain a specified and constant product size-range - Reduce the volume of a powder - Stabilize mixtures of powders: during handling and transport, the heterogeneous mixtures of particles lose their uniformity because of the variation in density, shape and size of the particles. The problems of segregation disappear - Improve the flowability of the powders, thus preventing problems of feed, dosage or packaging - Improve the compactability of some powders - Eliminate the problems of dust generation during handling - Control the hardness and strength of products - Control the dispersion rate of granules - Solve the problems of powder caking during storage
A commercial solution - Marketing
- Increase the sales appeal of a product - Facilitate dosage use: an agglomerate can represent the exact dose required in a process for ease of exact dosage
An environmental solution
- Recycle industrial waste - Recycle beneficiated dust in an industrial process - Eliminate pollution problems caused by airborne dust: air and ground pollution
An economical solution
- Replace the wet process of agglomeration involving costly drying and binder addition techniques - Allow more flexibility in the choice of raw materials purchased at the most attractive price (compound fertilizers) - Adapt easily and quickly to a wider range of mixed fertilizer formulas - Granule products that cannot be granulated by means of other techniques (wet process) - Upgrade by-products - Reduce the packing, storage and transport costs thanks to a volume reduction and higher density of the product - Avoid loss of product in dust form
From a long experience of design and construction of double roll presses, SAHUT-CONREUR has developed a roller press specifically adapted for grinding. This machine can crush materials of variable size range. The material fed between the rollers is ground and comes out as friable flakes.
Compared with traditional techniques, the use of this process means:
> Energy savings up to 30% for some materials.
> Throughput increases of crushed end-product from 30 to 100% when the
process is fitted into an existing grinding circuit.
> A cost decrease of production and maintenance of these installations.
The grinding with Roller Press can be installed either in a new plant or an existing one by replacing old technologies.
Fields of application
You will find in this page, examples of industrial applications using our grinding technology. Of course this list is not exhaustive and we hope that you will not hesitate to contact us in order to obtain more technical information about ways to process your product:
The briquetting units shape fine materials into larger forms of varied shapes, sizes and volumes (from a few cc up to 600 cc and more) : these characteristics are defined according to the product end use.
If the cohesive forces (particulate cohesion, valence forces, recrystallization, van Der Waals forces…) between the particles are low, a binder has to be used before agglomeration. The physical properties of the feed material, the end use of the briquettes and the cost of binder addition have to be taken into account before a selection is made. A large variety of (liquid or solid) binders is offered: starch, bentonite, bitumen, lime, cement, water, flour, lignosulphonates, molasses, polymer, resin, sodium silicate, etc…
The briquettes are obtained at a low or high pressure and can undergo mechanical or thermal treatment according to the characteristics of the processed material, the binder used and the desired end product. Considering the large variety of products to be processed and the binders used, the range of mixers designed and proposed by SAHUT-CONREUR is specifically adapted to each type of briquetting:
Vertical mixers or pug mills, for instance for briquetting of coal with bitumen.
Twin screw mixers, for instance for briquetting of some chemicals with water ; these mixers can be equipped with heating or cooling jacket, as the case may be.
Horizontal or ploughshare mixers, for instance for briquetting of some minerals with molasses ; these mixers can also be equipped with heating or cooling jacket, as the case may be.
Fields of application
You will find in this page, examples of industrial applications using our briquetting technology. Of course this list is not exhaustive and we hope that you will not hesitate to contact us in order to obtain more technical information about ways to process your product: