The ANDRITZ HQ-Press bark press processes bark at an approximately 5%-units higher dry solids content than any other competitive unit. While conventional presses typically achieve an annual average of 40% dry solids, the HQ-Press is able to deliver an annual average of 45% dry solids in normal operation. This can increase the net green energy value of the bark up to 15%.
Unlike competitive units which have enclosed structures, the HQ-Press has an open, simple design. The components are easily accessible for maintenance. As a side benefit, the open design helps with housekeeping activities. The design of the HQ-Press features a self-orienting drum with two-phase pressing to achieve the higher dryness. Advanced controls on the unit maximize the output under a variety of operating conditions.
Bark processing systems
ANDRITZ offers several systems for preparing bark for combustion or other downstream uses.
Maximizing bark as a fuel source
ANDRITZ has developed equipment to maximize bark quality so that it can serve as a valuable biomass energy source for boilers or gasifiers. This includes:
- Bark presses
ANDRITZ BioCrushers utilize their whole width for the crushing of the raw materials. This significantly reduces plugging due to variations in material quality and/or feed consistency. It also results in more even wear on the crusher knives, which means less frequent maintenance and knife changes. The enclosed design, no exposed moving parts, improves work safety while also reducing dust. The rugged construction also helps reduce noise and vibration.
Vertically-fed BioCrusher (BSX)
The vertically-fed BioCrusher BSX is designed for high capacity crushing of bark and breakage from the debarking process, including difficult-to-handle wood species like eucalyptus and acacia. The unit crushes the wood material to uniform particle sizes.
Horizontally-fed BioCrusher (BSY)
The horizontally-fed BioCrusher BSY is designed for crushing forest residuals, waste from sawmills and panelboard plants, as well as round wood and branch bundles into uniform particle sizes. The unit is also suitable for crushing other pre-crushed wood-based material into smaller, uniform particle sizes.
BMV bark shredder
This sturdy bark shredder is right at home in the automated wood room. It is not sensitive to foreign objects and it produces a homogeneous bark supply. The BMV is designed to produce optimum bark particle size for burning. Bark is fed into the shredder from a conveyor and processed with a combination of hammers and knives. Most foreign objects are crushed by the hammers, but the swiveling rotor knives will swing away if a large uncrushable object enters the unit. As an added precaution, the upper stator hammers are flex-mounted, with an overload pin for safety.
Hooper bark shredder
The Hooper model shredder is been proven in over 150 installations worldwide. It has a wide range of capacities to ensure that it can be applied in virtually all bark shredding processes. The construction is rugged to ensure reliability. The infeed design allows the Hooper shredder to shred large pieces of bark and occasional small pieces of solid wood for use as boiler fuel or mulch. Pivoting knives swing out of the shredding zone when they hit rocks or metal, allowing the tramp material to discharge with minimum consequences.
Biomass screen oversize shredder (BSB) – ATEX design
The BSB shredder is designed to be used in biomass screening applications where a slow rotating shredder is required due to a potentially explosive environment (ATEX). Two rolls in the shredder crush and shred frozen lumps, oversize fuel particles, and occasional logs and stumps to suitable particle size for burning.