New vacuum coater for better liquids addition

Coating is an industrial process that consists of applying a liquid or a powder onto the surface of a product of any possible shape to convey new properties.

Liquid addition to pellets was previously done in standard drum coaters under atmospheric pressure. It was possible to add minor amounts of liquid to pellets, but some of the problems were uneven dispersion onto the pellets or the pellets had a wet surface and therefore started “sweating” during storage, etc. Last 90s vacuum coating was introduced into feed industry as an answer to the challenge of creating least possible leak points. It used vacuum technology to create a sub-atmospheric pressure environment and an atomic or molecular condensable vapor source to deposit thin films and coatings. The new and innovative technology gives more advantages than the existing technology.

Principle of vacuum coating process

After loading pellets, the preset level of vacuum is obtained in the coater vessel. Liquids then are added through nozzles on the machine, while the rotor is running to allow all pellets to be exposed in atomized liquids. After the distributing of liquids onto the surface of pellets, pressure inside the process vessel is controlled back to atmospheric and is pressing the liquid inside the pores of the pellets, leaving the surface dry. It allows for a deep penetration of liquid and equal distribution onto pellet products (see Fig.1).
 
Vacuum Liquid Coater now is widely used in the application of oil or fat, pigments, flavors, functional improver, vitamins, etc. onto pellets after drying and/or cooling, in order to improve the energy, the palatability and the functionality of feed products, especially aquafeed and pet food. It offers a possible and flexible tool for production of a wide variety of high quality products within a single production line.

FAMSUN new vacuum coater

There are many similarities between coating processes and numerous examples of technology transfer to and from the feed and food industry. FAMSUN PTZL3000 Vacuum Coater is developed by Muyang America R&D Institute for high addition of liquids, no product damage and highly profitable long term performance, which is in compliance with modern production requirements.

The vacuum coater system consists of a closed mixing vessel with a vertical screw rotor, an efficient spraying system, the vacuum system and control elements (see Fig.2). It is possible to increase liquid addition quantities up to 36% of dry matter weight with 6-12TPH capacity and low energy input.
 
Important features

The vacuum coater is a simple design with distinguished technical and functional advantages:

Strong vacuum creation and control ability, liquid addition up to 36%

With excellent sealing performance, vacuum created in the mixing vessel can be controlled within -950~0mbar. By switching the vacuum on, or regulating the valve to obtain different vacuum level, and turning the vacuum back to atmosphere, it is possible to ensure that liquids penetrate more deeply or less deeply into the granule. The liquid addition is ranging from 6% to 36% of dry material weight.

High mixing homogeneity, low product damage and free of contamination

Thanks to the vertical transport screw rotor and the efficient spraying system, all pellets are able to expose to atomized liquids or powders sufficiently and uniformly, which brings in a coating uniformity level up to 93%.

In addition, the low energy input of the rotor, the smooth profile of screw rotor, and the vessel chamber of no death corner assure that mixing is carried out with very low wear and breaking of the pellets and minimum residues when discharging, contributing to no product damage and thoroughly cleaning. It also allows for easy changing of formulas without the risk of cross contamination.

Precise process control for flexible production

The application of liquids is simple and flexible with the new PTZL3000 Vacuum Coater. The number of nozzles that installed on the top of coater for injecting and atomizing liquids is customizable and could be up to five groups. Thanks to the sophisticated control program, users can add several liquids onto feed pellets in combination with different vacuum levels (Table 2 is an example). Configuration for adding powders is also an option for the system. This makes it possible to use the vacuum coater, within a single production line, for the production of a wide variety of products, while quickly and easily switching from one recipe to another, which in turn enables users to effectively deal with a wide range of challenges.

The system is available of both manual and automatic control, with the liquids adding accuracy of 0.4% and pellets batching accuracy of 0.8%.

Profitable long term performance

In addition to the high quality feed products achieved and the flexible productions, the simple structure design and the precise automatic control as well as the long lifecycle of wear parts contribute to simple operation and easy maintenance. The unique discharge door structure ensures that there is no relative motion between door body and sealing elements, and it also facilitates door seal replacement.
 

More products like grinding machinery, pellet machine, extruding machine, feed mixer and other feed machines are available at Machineryshops.com.