Method and apparatus for separating wood bark from gravel

Abstract

Abstract A bark and bedding gravel mixture is dumped into a hopper and moves along an inclined vibratory conveyor onto a screening section which screens limbs and other large chunks of wood from the bark-and-gravel mixture as well as sand-sized particles. The limbs and wood chunks are reduced to chips and stored for later use. The sand is conveyed to an aggregate storage site for reuse as bedding material. The bark-and-gravel mixture is dropped from an outlet of the screening section toward but short of the infeed end of a vibratory conveyor table through an air stream which blows the majority of the gravel and bark onto the table while oversize rocks fall short of the table. The bark-and-rock mixture moves through vibratory action along the table into a gravel channel which is separated from a second, bark channel by a transversely inclined rampway forming a ridge between the two channels. An air stream directed across the gravel channel toward the rampway induces the bark portion of the mixture, which forms a stratified layer over the gravel under vibration, to move up the rampway and into the bark channel as both the bark and gravel travel downstream on the table. Sand is screened from the bark near the downstream end of the bark channel after the bark has been dried. The cleaned and dried bark moves from the downstream end of the bark channel to a hog which reduces the bark chunks to a size suitable for use as fuel. The gravel moves from the downstream end of the gravel channel to the gravel storage area for reuse in bedding a log storage yard.

Inventors

• 👤 G Crow

Bibliographic Details