The purpose of drying is to reduce the moisture content of the raw material or processed product.
By providing heat and gas flow over the dried substance, we are able to reduce the amount of a given solvent (usually water) in the product. Drying in industry changes the physicochemical, organoleptic and microbiological properties of the substance. It is used to reduce mass and size. It is one of the oldest methods of preserving food products. A properly conducted drying process can preserve most of the original features of the product. In order to correctly conduct the drying process, it is always necessary to select the appropriate drying method in terms of technology, and then the device so as to obtain the optimal energy and economic effect.
Fluidization is a process of creating a so-called dynamic suspension (fluidized bed) – small particles of a solid in a gas stream moving from the bottom to the top. Particles in the fluidized phase are in constant motion, constantly moving throughout the entire volume of the vessel, which gives the impression that this layer behaves like a “boiling liquid”. The phenomenon of fluidization is used to conduct technological processes requiring a large interphase surface and rapid heat exchange.
Fluidized bed dryer technology is mainly intended for drying bulk products, but not only. Such dryers allow for changing the moisture level of products and raw materials. A feature of fluidized bed drying is the high efficiency of processed materials. Fluidization allows for the creation of a large contact surface between the solid and gas phases, the so-called interphase contact). Fluidized bed dryer is the most energy-efficient solution, especially in the case of a continuous work system.
The operation of a fluidized bed dryer involves supplying warm gas/air to a perforated deck where the raw material or product being processed is located. The supplied medium creates a so-called fluidized bed, which, by acting on the product, causes its drying. A high temperature and increased pressure are created in the deck of the fluidized bed dryer. Additionally, for difficult products, the appropriate vibration movement provided by the fluidized bed dryer causes controlled movement of the product in order to obtain an optimal fluidization process. In this drying method, the product is intensively mixed with the gas, which guarantees high heat exchange and optimal speed of physical processes. Fluidized bed dryers are suitable for drying temperature-sensitive products and products with increased viscosity. The vibrations of the fluidized bed dryer help to break up oversized particles of the raw material, which could not be fluidized before, especially brittle and delicate materials. Fluidized bed dryers can create pre-fluidization conditions, preventing burn-through and discoloration of the material subjected to the drying process.
The feature of BIKO-SERWIS dryers is their design that allows for easy cleaning and maintenance. There is also a version available with a gas recirculation system and closed circuit for improved efficiency and recovery? The materials used in production ensure durability and functionality in use, while meeting even the most stringent technological and sanitary requirements. All the size and functional parameters of our fluidized bed dryers are adapted to the requirements set by our Customers.
Often we are dealing with a product in which the size of individual particles varies significantly and the moisture content is high. By combining the right gas flow rate and mechanical movement, bulk products with a wide range of particle sizes can be processed while generating negligible amounts of dust.
The fluidized bed dryer is also used in the treatment and refinement of waste products for reuse, e.g. in the production of animal feed or processing of grain sludge from breweries. Another application is the drying of coarse minerals such as sand and gravel. Our engineers have developed fluidized bed dryers in such a way that they provide optimal results while minimizing abrasion. The unique drive means that we can create a fluidized bed as large as the product requires.
