Microchips for Pellets
Pellet mill feedstock – the initial form and size of wood fiber for the start of the pellet making process, is primarily wood chips. Feedstock is often a blend of debarked chips and non-debarked chips in order to meet the pellet customer’s ash content specifications. Desired chip size varies depending on an individual mill’s secondary sizing and drying equipment and capabilities. The trend with most pellet mills has been to procure the smallest possible chips straight from the source. Overwhelmingly this has been from in-field microchips.
Microchips is a term used to describe very small wood chips ranging from 1/8” length to 3/8” length. These small chips can either bypass the first hammer mill processing or pass through the hammer mill increasing productive capacity. Smaller feedstock increased mill throughput for both hammer mill and drying operations. Microchips provide a range of fiber lengths and geometry needed to manufacture hard, durable wood pellets that can be effectively transported with a minimal amount of fines created from handling.
Peterson drum chippers have a proven track record in the industry for high productive capacity and reliable, uniformly sized microchips. In-field microchipping provides the highest possible utilization as most small stems, limbs, tops, and other logging residues are processed along with the traditional pulpwood sized stems. Loggers, landowners and timberland managers recognize economic and aesthetic benefits from increased utilization and fiber yield.
Portable microchippers have also proven to be effective backup for on-site pellet mill chipping (woodyard operations). If a mill chipper is down for maintenance or the mill needs extra chip production, a portable microchipper can be brought on site to process roundwood into the pellet mill’s required feedstock.
DRUM CHIPPER KNIVES & COUNTER KNIVES
A desired chip size can be attained by following our Knife Assembly Setup Guide for 6 and 12 pocket drum chippers. The guide recommends a particular combination of the Peterson Chipper Knife with a Peterson Counter Knife and Shim (if necessary) for chips ranging in size from 1/8” up to 1″. All Peterson chipper and counter knives are manufactured with an A8 Modified Steel which is heat-treated to balance hardness for maximum abrasion and impact resistance. The cutting surface maintains a razor-sharp edge throughout multiple chipped loads and then is re-honed and re-babbitted extending the service life of the knives.