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Shredders and grinders

These are used to reduce wood fuel material to small pieces for easier handling, volume reduction, or as a feed for conversion processes.

Shredders and grinders are designed for low grade hogfuel production. Hogfuel is unlikely to be suitable for most small and medium sized wood fuel systems, which generally use even-sized high quality wood chip. However, use of a screen can help to remove oversize pieces.

Shredders, grinders and hammermills can be high power, high throughput units, suitable for handling low quality, mixed material, particularly if it might be contaminated with stones or soil.


Has one or more rotating axles with teeth that tear apart wood material through a screen.

Stump grinder

Consist of a fast rotating tool which can pivot around an axle when too much resistance is met. Grinders are used to grind down large tree stumps such as during land clearance operations.


Material is forced through holes in a screen using hammers. Hammermills can be used to reduce woody biomass to small pieces prior to forming pellets.

Tub grinder

A general purpose grinder for use on a wide range of waste, including construction and demolition waste.