FILTERMAT® - combined spray dryer and belt dryer

The FILTERMAT® dryer for drying of hygroscopic, thermoplastic and slowly crystallizing food and dairy products

FILTERMAT® dryer 6.3 - combined spray dryer and belt dryer for small scale production and application development

Many dairy products, foodstuffs and food ingredients are required in powder form and yet some of them are difficult to spray dry due to their carbohydrate, fat or protein contents.

Continuous powder production of these types of products in conventional one- or two-stage spray dryers is often associated with product quality degradation, deposit losses and frequent cleaning procedures. Special technology is required to economically produce quality powders in an agglomerated, easy-to-handle form.

The FILTERMAT® spray dryer provides this special technology for:

• The most gentle product drying
• The most economical drying
• The greatest product application flexibility

The drying of hygroscopic, thermoplastic and slowly crystallising products involves handling of very sticky intermediate materials at a lower temperature level than that possible in conventional spray dryer layouts.

Completion of drying under these conditions requires the powder to be held within the dryer for a longer period of time.

The FILTERMAT® uses nozzle atomization in a co-current tower that directs the semi-dried particles downward onto a moving belt. The material is then gently conveyed as a porous layer through zones of post-drying and cooling, resulting in a crisp cake-like structure, that breaks up at the end of the belt and is discharged through a final particle size control system. The exhaust air streams pass through the material layer on the belt.

Product: Coarse or very coarse, agglomerated / granulated free-flowing dustless powders can be produced.

Production-scale FILTERMAT® dryer - microphoto: meat extract

The new version of the FILTERMAT® Dryer size 12.5, here shown with belt visible

How the FILTERMAT® Works

The feed liquid or concentrate is pumped to a high-pressure nozzle assembly and sprayed downward into drying air, entering at the top of the chamber. The air disperser creates an air flow pattern in the main drying chamber that directs the particles downward onto the moving belt. The first drying stage is completed during this phase.

Semi-dried particles accumulate on the belt as an agglomerated, porous powder layer. The drying air is exhausted through the powder layer and the belt, and thus drying continues while the powder is being conveyed (second drying stage).

Drying is completed in two chambers adjacent to the main chamber. Powder cooling and/or conditioning are carried out in the last chamber, where dehumidified air is used. The ability to control air temperature in chambers 2, 3 and 4 gives the FILTERMAT® much flexibility in the products that can be processed and the structure of the agglomerates.

After completion of drying and cooling, the powder falls off the belt, is milled if needed, and is sieved prior to being bagged or conveyed into silo storage.

The important feature of the FILTERMAT® is that, as the air flow flows down through the powder layer and belt, the finest of particles are thereby retained in the powder layer. Negligible powder passes with the exhaust air to the cyclones. Particulate emission levels are very low even though bag filters are not used.

The FILTERMAT® is equipped with full CIP equipment and meets the strictest sanitary design standards. Special attachments are also available, e.g., dry powder dosing.

Why FILTERMAT® Performance is Better

Investment involved in installing a FILTERMAT® spray dryer is extremely favorable since, compared with alternative spray dryers with fluid bed attachments that produce agglomerated powder, buildings of much lower height are required.

Download FILTERMAT® Data Sheet