Our small drying system is a simple belt dryer, but is unique in terms of hygienic design, “easy to cleane” and the great variety of applications it can be used for. All materials directly in contact with the product, are so-called Food Contact Materials (FCM), which means that the dryer is particularly suitable for drying, of foods and semilar products, which require maximum hygienic standard. Overall the dryer can be used for drying and heat treatment of all products, which can be contained by the belt. However, not liquid products, and products that can exhaust flammable gases.
The dryer is designed specifically for testdrying and smaller productions, wherefore the capacity is limited to 40 kg water evaporation per hour. If you need more capacity, you can connect several dryers in series with each other. The drying chamber is equipped with three inspection sections, wherein one can see the product all the way through the dryer.
The entire front of the dryer can be opened via the control panel that activates two electrical actuators. In this mode the conveyer can easily be lifted out for possible service and the entire drying chamber can be cleaned easily. Below is a picture of the dryer with the front door open. Here you can also see the infrared heating module in the erect position.
The dryer is a convective belt dryer with the possibility of supplying infrared heat. The convective drying is carried out by recirculating warm and dry air through the belt, and the product lying on the belt to be dried. The belt is woven from Teflon coated glass fiber strands, which can be ordered with mesh sizes of 1, 2, 3, 4 and 5 mm. There are two semi-independent temperature zones in the dryer. The first one in first half of the dryer and the second in the last half of the dryer. In the front and the rear quarter of the dryer the drying air flows upward and in the middle half the drying air flows downward. This dries the product efficiently and uniformly. This is illustrated in the drawing below.
In order to ensure sufficient drying capacity of the drying air, fresh outside air is fed continuously into the drying chamber, and semilarly moist air is sucked out of the drying chamber. The two air streams exchange heat in a regenerative heat exchanger. Both the recirculation, the fresh air and exhaust air is continuously filtered, so the risk of accumulation of dust is eliminated. All three fans are controlled by frequenzy converters and adjusted via the control panel. If you want to use the 24 kW powerful infrared heating module, it should be lowered in a horizontal position so that the product can be heated evenly over the entire belt surface. Infrared heat penetrates a small distance into the product surface where the heat is dissipated. So depending on the product characteristics and geometry, infrared heat be a highly effective way to add heat, and especially in thin products.
In the front door a surface temperature sensor is located which continuously measures the surface temperature of the product at the outlet of the dryer. This is used as an input for controlling the infrared heat output.
You can store all the settings you want, so you can quickly restore some settings suited to a specific product. For further information download the data sheet below or contact us.
The dryer is designed for educational purposes at the Academy of Business in Aarhus, and is also suitable for mini-scale product development tests. The dryer can both dry with hot air up to 200 degrees and furthermore with superheated steam at atmospheric pressure. The dryer also has a coating function, so that you can both dry and subsequently coate the test product. Below is a picture of the drying chamber itself. The product is placed in a product holder, which is an D80 x 100 tube with a funnel that prevents the products from being blown out of the pipe.
The product holder hangs in a road cell so you can follow the weight of the product during the drying process. When registering the weight, turn off the airflow so that the weight is not disturbed by the air’s dynamic pressure. Below the product holder is a spray nozzle used for coating. Download data sheet below: