Re-circulating batch dryer
What is a re-circulating batch dryer?
A dryer is a mechanical device or machine that removes the water from wet grains by forcing either ambient air or heated air through the grain bulk. In a re-circulating dryer, the same quantity of grain is re-cycled through the dryer until the final moisture content is reached.
What are the advantages of a re-circulating batch dryer?
Re-circulating batch dryers have a number of advantages over the cheaper fixed-bed batch dryers:
The principle behind the re-circulating batch dryer?
As illustrated below, the grain is constantly moving through the drying bin from top to bottom, passing first the tempering section and then the drying section. Retention time for one pass is around 60 min. Drying rate is around 1−2% per hour. Drying air temperature is up to 55°C.
Types of re-circulating batch dryers
Depending on airflow relative to grain flow, there are two different types of re-circulating dryers (Fig. 1):
Components of a re-circulating batch dryers
A re-circulating batch dryer consists of:
Prepared by M Gummert with inputs from JF Rickman (2004); updated by M Gummert (2010)