Design and testing of a sawdust dryer and a suspension sawdust burner

The objectives of this research were to modify and test a prototype sawdust dryer designed by Arrowhead Forest Products and a sawdust-fueled suspension burner developed at Virginia Tech. The dryer was designed to process green sawdust at small to medium-sized sawmills and pallet mills. The sawdust burner was designed to be the heat source for the dryer and serve more general needs.

A series of trials were conducted to develop the operating parameters of the dryer and measure the dryer's effectiveness at reducing moisture content to 0%. Separate tests were conducted on the burner to determine maximum heat outputs and combustor efficiencies using sawdust fuel of various moisture contents and particle sizes.

The sawdust dryer proved capable of reducing the moisture content to 0% after several passes through the system. The sawdust burner produced close to 400,000 BTU's/HR at calculated efficiencies over 90% and proved relatively insensitive to ranges of fuel moisture contents and particle sizes.