There is a common drum dryer working principle for using a single drum dryer. Generally, this is done by adding the slurry that will be drum-dried. This could be something like starch, flour, oats, or anything else you wish to use a drum dryer for. The starchy slurry is fed to the application rolls, which means that this starch-rich slurry will stick to the applicators.
Then, as the drum rotates, this will mean that the slurry gets stuck to the surface of the drum. As the drum continues to rotate and move around, the layer attached to it begins to dry completely. When finished, this can be extracted from the drum dryer simply by scraping it off and then placed into a breaker. Using a fan also helps to remove any vapour produced by the drier as it works; this is expended via a hood into the roof and out into the open air.
To ensure the best single-drum dryer working principle, the temperature is indirectly kept at a constant level. This is done by controlling the pressure level within the drum itself. Starch cells are transferred to the drying drum via the contact zones of the applicator. The layer being dropped onto the drum itself is then kept at a steady temperature thanks to constant contact with a heated surface. This means the drying time is extremely quick and simple compared to other methods.
This is one of the main reasons why using a drum dryer can lead to a dried product that retains its quality and taste. Other drying methods can almost burn the produce dry, leading to a drop-off in product quality. With a drum dryer, though, the technique mentioned above helps to make sure that nothing is burnt or overly dried.
Thanks to the single drum dryer acting as a separator, too, this helps to ensure that non-cooked starch fragments are not transferred into the drum itself. This means that they retain their position on the rotating layer on the applicator rolls. This helps to ensure that the applicator rollers – of which there can be anything from two to seven present in a single drum dryer – help keep the right balance.
The end result is that you are left with a product that dries out properly without impacting the quality, consistency, or usability of the food product itself. Ensuring that non-cooked fragments are not transferred into the drum helps ensure that the dried-out starch is good to be used once it has been scraped out of the drum dryer.
The general working principle of drum dryer appliances, then, is simple to follow along with and to use in your day-to-day operations. The drum dryer working principle explained above can provide useful information to understand precisely how your equipment operates.
By making sure that the heating process is as consistent as possible, there is a certainty that you can get the right level of heat and dryness applied to the starch goods that you wish to have dried out properly.