Required killing equipment & modern single deck kilning

Circular Double Deck Kiln Overview

  • A circular double deck kiln is essential for the malting process, regardless of batch size, kiln cycle, or vessel configuration.

  • Key components include:

    • Perforated kiln floor: Allows for necessary airflow through the grain bed.

    • Even grain bed: Distributes airflow evenly, creating resistance for airflow.

Airflow Requirements

  • **Kilning vs. Germination: **

    • Kilning requires approximately 10 times the airflow needed for germination.

  • Variable Speed Kiln Fans:

    • Located on the top of the kiln, these fans:

      • Pull heated air from kiln heaters through grain beds.

      • Discharge used air through heat exchangers to recover heat, enhancing efficiency.

Process Control and Cooling

  • Flexibility in Airflow Control:

    • The fans can adjust for varying humidity levels, maintaining temperature stability.

    • Reduced fan speed can help control and hold consistent temperatures.

  • Bypass Louvers:

    • Allows for adjustment of temperature between curing and withering decks, separating process influences.

  • Cooling Process:

    • Cool air is introduced post-curing to stabilize color and enzymes in the malt.

Ending the Kilning Cycle

  • At the end of curing:

    • Heaters are turned off.

    • Warm air is diverted through heat recovery systems.

    • Ambient air is then introduced for the cool-down phase.

  • Unloading Mechanism:

    • An unloading machine removes the finished malt via an auger from the outside to the center, facilitating efficient discharge.

Comparison to Single Deck Kilns

  • Double Deck Kilns:

    • Commonly used for producing pale malt in batches but lack flexibility for varying malt types.

  • Modern Single Deck Kilns:

    • Offer enhanced process flexibility for different malt types due to:

      • Heat recovery systems.

      • Air recycling from fan discharge back to kiln inlet.

    • While energy efficiency may not match double deck kilns, the adaptability makes single deck kilns increasingly popular in malting.