Continuous Kilns

Continuous Kilns
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American Wood Dryers offers a unique and patented type of Continuous Dry Kiln (CDK) referred to as a Single Pass™ . Compared to the older technology of the counter flow design where wood enters the kiln on opposite ends and on opposite tracks, the Single Pass kiln design allows all wood to enter at one end and discharge at the opposite.

Single Pass CDK advantages are:

• Improved Mill Flow with dedicated green and dry ends like batch kiln operations
• Reduced material handling labor and equipment costs
• Reduced drying energy cost
• Improved grade recovery

Continuous
Counterflow Kilns
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The Single Pass kiln is divided into three sections and partitioned by baffles mounted on hinges and tensioned with springs. The first section is a preheat chamber where wood is brought up to operating temperature. The second or center section is outfitted with a heat source and is where the actual drying takes place. The third and final section conditions the dry wood to equalize moisture content and relieve the drying stresses.

Air circulation fans are mounted along the entire length of the kiln. Fan motors are mounted on the kiln exterior to facilitate maintenance without shutting the kiln down.

Exhaust hoods are provided at each end of the kiln to disperse wet air and reduce water condensing and accumulating on the ground.

Lumber is transported through the kiln on carts. Carts are moved by a Pusher with a hydraulic cylinder and pawl arrangement located below and between the cart rails. The cylinder is fitted with a transducer and advances the load incrementally by the PLC control system. Speeds are typically in the 3’ to 8’ feet per hour range and adjusted depending on incoming and target moisture content. The 2 tracks can be operated a different speeds to accommodate different moisture profiles.

Kiln Heat Energy Systems for Direct Fired Kilns

• Green Sawdust burners
• Dry Shavings burners
• Natural Gas burners
• Steam and thermal oil