Method for coloring wood chips using a screw conveyor
AssigneeKurtz Bros., Inc.
InventorGreg Rondy
Life of this patent
Estimating the term…
Abstract
Comminuted wood is converted to a colored wood product useful as a mulch by feeding the comminuted wood into the lower end of an angularly upward positioned screw conveyor having an internal auger. The comminuted wood is contacted in the lower end of the conveyor by a liquid color-imparting agent, preferably an aqueous solution containing iron oxide pigment, carbon black pigment or a mixture of both pigments. After contacting, rotation of the auger draws the moist colored wood product towards the upper end, permitting runoff of excess liquid agent, which returns by gravity to the basin for further contacting with newly-fed comminuted wood. Colored wood product discharges through a chute at the upper end of the conveyor for further drying, if necessary.
Claims12
A method of preparing a colored wood product, useful as mulch, comprising:
- a) feeding comminuted wood into a screw conveyor having a first end and a second end, said screw conveyor further having a helical auger disposed axially and in a close fitting relation to the internal surface within a generally closed channel with a feed port near said first end and a discharge port near said second end, said helical auger capable of being rotated by a drive means, wherein the comminuted wood is fed through the feed port into said first end of said conveyor;
- b) contacting said comminuted wood with an aqueous color-imparting solution containing at least one color-imparting agent therein for sufficient time to disperse said color-imparting solution upon the surfaces of said comminuted wood to create a colored wood product, said contact occurring at least at said feed port through a feed port nozzle means substantially traversing said feed port and providing a gravity feed sheet of said color imparting solution from a longitudinal slot formed therein:
- c) rotating the auger so that said colored wood product is drawn from said first end toward said second end, during which process any excess said color-imparting solution drains away from said colored wood product, effectively drying said colored wood product into a moist colored wood product;
- and
- d) discharging said moist colored wood product from said screw conveyor via said discharge chute and further drying said moist colored wood product, if necessary.
Dependencies are inferred from the claim text.