Kilning Technology Flashcards
What is the primary purpose of modern kilns?
To produce high quality malt using the minimum amount of energy.
Describe the design of early kiln models.
Often rectangular boxes in a double deck arrangement, where exhaust from the first layer is directed to the second layer.
How do modern kiln designs differ from early designs?
Many have a single floor similar to circular germination vessels.
What is the role of the beam in modern kilns?
It loads the green malt in an even layer on a perforated floor.
What is the importance of a level bed in a kiln?
It allows an even air passage through the bed.
What is the typical bed depth in a kiln?
0.75 m.
What is the bed depth of a germinating vessel?
Approximately 1 m.
What type of fans are used in modern kilns?
Large centrifugal fans.
What is the function of the pressure chamber in a kiln?
It forces air through the malt bed.
How much air is required when kilning starts?
About 4000-5000 m3 of air per ton of malt per hour.
Through what mechanism is air heated in a kiln?
An indirect heat exchanger, often a gas or high temperature water heat exchanger.
What does the grain bed’s permeability to air do as it dries?
It increases.
What happens to warm, moist air leaving the grain bed?
Most of it is vented to the atmosphere, but energy is recovered through heat exchangers.
What materials are the heat exchangers made of?
Glass or stainless steel.
What is the purpose of the heat exchangers at the kiln fresh-air intake?
To pre-heat the incoming fresh air.
How is malt discharged from the kiln?
Through the bottom of the kiln deck for final processing.
