Systems designed specifically for chipping, grinding or shredding scrap rubber into clean-cut nominal pieces has become a solution both in cost savings and increased production for many alternative fuel (AF) companies such as cement kilns, steel mills, pulp and paper mills, electric arc furnaces and waste-to-energy facilities. Discarded tires are known for collecting water, which is the perfect breeding ground for mosquitoes and associated diseases they can transmit. Recycling tires can also help eliminate unsightly and hazardous tire piles. Co-processing tire-derived fuel (TDF) as an alternative energy source at facilities not only lowers fuel costs in a sustainable manner, but has direct benefits for the environment.
Columbus McKinnon (CM) has been manufacturing tire recycling equipment since 1982 and has installations in place at many of the largest AF corporations worldwide. “The CM-patented Holman knife design separates the firm from the competition, as CM is known for the extremely close knife tolerances which provide clean-cut material with minimal exposed tire wire. Chips can then be fed easily and cleanly into the kiln feed of a cement company or other high heat furnace without chance of ‘bird nesting’ or clogging where the TDF is introduced into the system,” said Kaytee Moran, equipment sales.
Depending on the volume and size of TDF required on one side, and the operational and market constraints on the other, CM can provide the proper equipment to meet the AF user’s specifications. CM tire recycling equipment can process a wide array of tire sizes from passenger car tires up to OTR tires 1,525 mm in diameter producing 2” nominal, clean-cut tire chip production rates of approximately 10 to 12 tons per hour.
CM’s four different shredders include: a primary shredder that processes passenger car, SUV, truck and super singles along with some smaller OTRs and provides initial size reduction for further processing; a dual speed shredder, which is an all in one system for processing passenger car, SUV, light truck and semi-truck tires whole into clean-cut chips in a variety of sizes ranging from 4” to 1” in size; a single speed shredder and a chip shredder that can process whole passenger car, SUV and light truck tires into clean-cut chips – or that can be used after a primary shredder to further chip pre-shredded material into final product such as clean-cut TDF.
Cumberland’s total product array of granulators, shredders, pulverizers, briquetters and integrated reclamation systems include low and standard speed operations, and a variety of rotor styles: screenless, open rotor, hog rotor and helical shredder rotors. Their most popular granulator models are the X Series units, T500 Series units, and beside-the-press units. “Our annual production volume is approximately 600 units per year,” reported John Farney, national sales manager.
He said the 74-year-old company has the largest installed equipment base in North America. All anticipated and to-date compliance regulations for safety and machine functionality are met in units supplied to operations ranging from the smallest volume medical molding facility, to the largest recycling operations.
“The most important challenges for users are timely and safe maintenance, maximum throughput and high quality regrind. Our units address these concerns with the safest maintenance procedures, the largest capacity performance units and our chamber/rotor designs, which offer the best granulate after processing. We’re leaders in design technologies and are dedicated to optimizing material processing and safety for users and maintenance technicians,” Farney said.
He noted that the market demands quality final material, the lowest possible energy consumption and the lowest possible sound level creation. “Design elements are stressed for maximum effect in each of these areas. With the most thorough and complete product array in the market, there is virtually no application for which we cannot provide a solution. With designs that stress durability, long life and high performance, we are proud to be the market solution provider for routine and complicated applications,” stated Farney. Cumberland provides equipment to injection molding, recycling, thermoforming, extrusion and rotational molding industry sectors.
Granutech-Saturn manufactures a wide range of products for processing scrap rubber, including tires, all the way down to a fine powder, if required. Primary reduction equipment includes rotary shear shredders that handle tires or other rubber that may be contaminated with steel, and a roto-grind single shaft grinder, which reduces clean rubber down to less than 1” in size.
Secondary reduction equipment includes the new Super 80 Grizzly, which can reduce up to 10 tons per hour of tire shreds to a less than 1” product size – and separate out nearly all steel content. Their third-stage G3 granulator reduces less than 1” size material to less than 1/4”, and their fourth stage reducer is a powderizer. The machine takes in material under 1/4” in size and reduces it down to sizes ranging from 10 to 30 mesh.
Granutech’s Refinermill product reduces 1/4” and under material to sizes between 10 and 60 mesh, if needed. Depending on the final size product needed, typical production volumes may fall in the 2 to 10 tons per hour range. Greg Wright, sales director, discussed some industry trends he’s noticed. “Working with uncured rubber is a challenge due to its sticky and gummy nature. Also, our customers sometimes run into permitting issues at the local level, especially when air systems are involved. Final product cleanliness – when working with tires – is important to our customers. They want a fiber and steel-free end-product. Our solution for that is a complete system with equipment that effectively removes steel, fiber and other contaminants. The end result is an extremely clean final product. Rubberized asphalt is a market that has been around for a while but still has plenty of room for growth. We talk to people all the time that are working on de-vulcanization and pyrolysis methods. An economics versus efficiency challenge exists, but it is coming along.”
Established in 1982, Rotogran is a manufacturer of size reduction equipment for the recycling industry. The firm provides single-pass, high-capacity granulators capable of reprocessing scrap into valuable regrind, regardless of its original shape or size. According to Mike Cyr, vice president of sales, “Rubber tire recycling is an evolving market in which technological changes emerge almost daily. Rotogran designs and builds specialized granulators to work in conjunction with rasping machines to produce a viable final product. Recently we built a granulator that is producing 4,500 lbs. of rubber granules per hour, between 8 and 30 mesh, through a 1/8” diameter hole classifying screen. The rubber is introduced into our granulator after it has been pre-sized by a rasper to approximately 1/2” pieces. This process can eliminate the need for a cracker mill – a considerable savings in cost.”
Cyr also noted that high throughputs are achieved with Rotogran design features like an offset cutting chamber, double scissor cut blade design, and a nine-row multi-blade open rotor. The water-cooled chamber of the unit, bearing flanges, stationary bed blocks and rotor manage the heat often generated via rubber granulation. He said that factory-mounted heat sensors allow full process control for optimum granulator efficiency and performance. “Our internal chamber mounted pathway deflector is an innovation which guides the particles around the cutting circle and directly back into the first stationary bed blade. This unique feature provides maximum throughput, as opposed to the random and inefficient scattering of regrind common to most granulators,” added Cyr.
All wear surfaces of the Rotogran granulator are protected with easily replaceable wear inserts which can also be tungsten carbide coated or made from high grade alloys for extended wear life and protection of the initial investment.
Cyr said, “Recyclers demand rugged, solidly-built equipment that will withstand extremely harsh conditions and they seem to prefer the durability and value of North American-built equipment over risking the failure often associated with products built offshore. When a disaster strikes, the ability to source parts and quickly return to production is crucial to survival in this market. Rotogran International supplies heavy-duty equipment that exceeds customer expectations in durability and reliability, but we are also sensitive to today’s economic reality. All of our products are 100 percent designed and manufactured in North America.”