Beehive burner

A wood waste burner, known as a teepee burner or wigwam burner in the United States and a beehive burner in Canada, is a free-standing conical steel structure ranging from 30 to 60 feet in height. They are named for their resemblance to beehives, teepees or wigwams. A sawdust burner is cylindrical. They have an opening at the top that is covered with a steel grill or mesh to keep sparks and glowing embers from escaping. Sawdust and wood scraps are delivered to an opening near the top of the cone by means of a conveyor belt or Archimedes' screw, whereupon they fall onto the fire near the center of the structure.

Teepee or beehive burners are used to dispose of waste wood in logging yards and sawdust from sawmills by burning. As a result they produce a large quantity of smoke and ash, which is vented directly into the atmosphere without any sort of scrubbing or cleaning, contributing to poor air conditions wherever they are used. The burners are considered to be a major source of air pollution and are being phased out in most areas.

Teepee burners went out of general use in the Northwestern United States in the early 1970s, and are prohibited from operation in Oregon, as well as southwest Washington state. The wood waste is now used as a component in various forest products, such as pellet fuel, particle board and mulch.

Sawdust burner in Balaclava, Ontario, Canada

Wigwam burner in Halfway, Oregon

Wigwam burner in Drain, Oregon

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