Unidirectional multi-path lumber kilns

An apparatus for drying lumber charges, comprising:

• an elongated enclosure having a first chamber, a second chamber, first and second charge portals disposed in a proximal end of the elongated enclosure, third and fourth charge portals disposed in a generally opposite distal end of the elongated enclosure, and a longitudinal axis;
• a first guide member extending from the first charge portal to the third charge portal through a first side of the elongated enclosure, wherein the first guide member defines a first flow path;
• a second guide member extending from the second charge portal to the fourth charge portal through a generally opposite second side of the elongated enclosure, wherein the second guide member defines a second flow path oriented generally parallel to the first flow path, the first and second flow paths extend in a first direction through the elongated enclosure, and the first and second guide members are disposed on generally opposite sides of the longitudinal axis;
• and
• a first insulating member operatively coupled with the third charge portal, the first insulating member configured to reduce airflow through the third charge portal.

A method for converting an existing kiln to a unidirectional multi-path kiln, the method comprising:

• coupling at least a first chamber to at least a portion of the existing kiln to form an elongated enclosure with a first end, a generally opposite second end, and a longitudinal axis extending through the first and second ends, wherein the first end includes a first and a second charge portal and the second end includes a third and a fourth charge portal, and the longitudinal axis defines a first side and a generally opposite second side of the elongated enclosure;
• installing first and second guide members within the elongated enclosure such that the first guide member extends through the first side of the elongated enclosure from the first charge portal to the third charge portal along a first flow path, and the second guide member extends through the second side of the elongated enclosure from the second charge portal to the fourth charge portal along a second flow path;
• and
• operatively coupling a first insulating member with the third charge portal, wherein the first insulating member is configured to reduce airflow through the third charge portal.