Chippers and grinders are used in the processing of organic materials, such as those commonly found in municipal biomass or in waste-to-fuel operations. Chippers typically produce a thin, uniform, rectangular-shape product. The machines are not tolerant of non-wood contaminants and can be damaged when exposed to those materials. Small chippers process items such as branches and large chippers can process whole trees but generally not waste materials.
Grinders, usually high-speed hammermills, break wood into various sizes, resulting in a shredded appearance. Unlike chippers, grinders tend to be quite tolerant of non-wood items such as dirt, rocks or nails. The machines are typically available in vertical or horizontal feed designs, and in stationary or portable configurations.
Art Murphy is the marketing manager at Continental Biomass Industries (CBI). The company manufactures equipment for a variety of grinding, chipping and shredding needs. After the success of CBI’s Magnum Force 6800 grinder, the company went back to the drawing board to apply the same principles to a machine designed for lower production needs or transportation restrictions. The end result of that effort is the Magnum Force 5800 – a mid-sized, strong, upswing grinder.
“The offset helix rotor, anvil and screen designs and dimensions remain similar to the 6800 to retain its superior grinding performance, however, the rotor width is decreased to produce a machine with a total width under 8’6”. Each component was scrutinized, weight was engineered out where it wasn’t needed and engineered in where it was. The 5800 weighs 64,850 lbs. with the capability of producing up to 100 tons per hour,” Murphy stated.
The grinder is engineered for land clearing and logging companies and yard waste and demolition wood processors, and mulch yard customers who demand high-volume throughput and maximum reliability. The 5800 features a high lift upper roll for ease of maintenance; high torque, hydrostatic feed system; PT Tech hydraulic PTO; and a Caterpillar engine. High strength drum rotor and screen system are shear pin protected. The entire system is controlled by CBI’s IntelliGrind logic, incorporating a variable infeed speed that automatically adjusts to engine load and an optional modem communications system that provides for real-time system diagnostics. Murphy noted, “The 5800 meets specific size constraints but still provides all of the design features and ingenuity that makes strength and performance of CBI machines legendary.”
Vecoplan designs, engineers, and manufactures drum chippers, and both vertically fed and horizontally fed rotary wood grinders. Their VTH Series drum chippers produce high quality chips for the production of fuel, chipboard, paper and wood pulp.
According to Kim James, marketing/communications director, “The production of alternative and renewable fuels from any type of biomass, but especially wood is one of the biggest trends in this industry.” He said the most common application in the U.S. for their VTH drum chippers is in plants producing wood pellets for export.
“Disk chippers are more commonly used in the U.S. Drum chippers differ from traditional disk chippers because drum chippers are more universal. They can handle all different types and shapes of wood without any change to the machine while disk chippers are only useful for straight logs without branches. When comparing similarly sized machines, drum chippers can handle larger diameters than disk chippers,” explained James.
Vecoplan’s VAZ series rotary wood grinders are used in a wide variety of applications from simple volume reduction of wood waste prior to land-filling or composting, to preparing wood and other biomass for conversion to alternative fuels including pellets, cellulosic ethanol and other second generation bio-fuels. Grinders are also used to produce simple boiler fuel, animal bedding, mulch and material to be used in the production of particleboard or other composite materials such as wood or plastic decking. There are 12 grinder models to choose from, available in hundreds of configurations. The VAZ series grinders feature true dump and run operation. Fed vertically via a hopper positioned above the cutting chamber, the user can dump material into the hopper, push a button and walk away.
Vecoplan also offers the VTH-VU series horizontal wood grinders. The machines are designed specifically for size reduction of wood strips, edge rippings, slabs and all long wood scrap, as well as lineal plastic scrap such as siding and vinyl widow profiles. The VTH-VU series contains 6 different models, ranging from 40 to 125 hp. Infeed widths range from 12” to 33”. Larger, custom models are also available.
“The processing volume of our customers varies widely from the small woodworker processing a few hundred pounds of their own wood waste scrap in a year to the City of Edmonton which will produce 100,000 dry metric tons of refuse derived fuel per year, using their Vecoplan Alternative Fuel Feedstock Preparation system,” James noted.
Vecoplan was founded in 1969 as a manufacturer of innovative, high quality wood chippers. The company has a global array of agencies and there are over 10,000 Vecoplan machines and systems in operation throughout the world. “If you are involved in recycling, processing alternative fuel feedstocks, or any type of waste processing, Vecoplan is your best source for cutting-edge technologies to do it better and a partner to grow with,” said James.
West Salem Machinery (WSM) manufactures vertical and horizontal grinders, shredders, hammermills, trammel, disc and oscillating screens and vibrating conveyors/screens.
“WSM has over 65 years of experience designing and manufacturing the most rugged machinery and complete recycling systems available, with the application expertise and flexibility to customize the right solution for our customers,” said Mark Lyman, president.
Lyman reports that WSM grinder designs feature heavy steel housings, fully machined rotors, massive alloy steel hammers with replaceable/rebuildable tips, heavy-duty modular sizing screens and unique pivoting top cases for quick and easy maintenance to the inside of the grinder.
“One of our customers at a large, high-tech, recycling plant is processing C&D waste into value-added end products with two large WSM vertical grinders. The complete grinding systems include two 500-hp grinders with infeed chutes, support structures, access platforms, and motor starters to turn the pre-sorted C&D and urban wood waste into boiler fuel and mulch products – at 80 tons per hour,” Lyman said.
To help customers reduce operating costs and increase energy efficiency, WSM offers complete systems using screening and size reduction technologies. “These highly efficient systems are ideal for many types of materials including green waste, food waste, C&D waste and urban wood waste. WSM Grinders are part of a complete recycling system that can process RDF, MSW, land clearing, biofuels, wood energy, green waste, cellulosic ethanol, and fiber for densified fuel,” stated Lyman.
In response to the emerging trend in food waste recycling, WSM offers BioPrep™ Systems, specifically designed to provide complete fiber preparation of food waste and organic waste for anaerobic digestion. Lyman said BioPrep is unique in that it features mill duty screening, shredding and milling machinery to deliver properly sized feedstock for the biofuel/biochemical conversion process. In WSM’s screening and size reduction test lab, customers can have various feedstocks tested to improve their operations and help make informed machine purchases. Lyman noted that for green or dry wood fiber preparation; biomass fuel preparation; fiber prep for pellets, briquettes, or co-firing; converting ag-residuals for bio-fuels; mulch processing; animal bedding; or other fine-grind materials, the lab can simulate various size production settings and determine production rate and volume, and provide detailed screen analysis.