Design and functioning of low pressure superheated steam processing unit
Tang, Hin Yat
Superheated steam (SS) drying of distillers’ spent grain (DSG) is a more energy efficient alternative to conventional hot air drying. SS drying at sub-atmospheric pressure (also referred to as low pressure) can prevent burning and lowering the quality of the food product. The objective of this study was to design, fabricate, and test a SS drying system that could operate at sub-atmospheric pressure for drying DSG. After the custom designed system was constructed, major problems associated with the system were identified. A number of tests were carried out and modifications were made to the system to resolve technical problems. Distillers’ spent grain was then successfully dried using the system under various levels of temperature from 95 to 115°C and pressure of either -25 or -20 kPa, with a SS velocity from 0.100 to 0.289 m/s.
Distillers' spent grain, Superheated steam, Vacuum, Low pressure, Sub-atmospheric pressure