In the last several decades, the recycling industry has seen a steady rise in demand for recycled materials as well as an increase in the number of end-user items and materials facilities are capable of recycling. Businesses, retail locations and manufacturers are realizing the financial and environmental benefits of recuperating lost material, energy and investment by participating in recycling programs and purchasing reconstituted raw materials. Recycling facilities are key in this process, providing a variety of sorting, shredding, baling and refining services. Because recycling processes require many specialized types of equipment, recycling facilities tend to specialize in sorting and baling materials to be shipped out for further processes, or facilities specialize in reclaiming one type of material, such as PET, aluminum cans or cardboard.
Different types of industrial equipment are used for metal recovery, plastic recovery, pulp recovery and other reclamation processes. Initial sorting stages for material recovery use conveyors, vibratory feeders, magnet assemblies and downstream trommel screens or mixers which separate parts by size and material. While machine vision systems may be employed for robotic sorting, the most cost-effective methods of sorting materials involve both conveyorized screening and manual sorting. Once sorted, materials are reduced in size by shredders, grinders or pulverizers, mixed with water and/or refining chemicals, melted, extracted and re-extruded, rolled or forged into raw plastic pellets, metal ingots or paper rolls.
Aside from traditional paper, plastic, glass and metal recycling, there are facilities capable of recycling consumer items such as ink cartridges, batteries, light bulbs, carpet and computers as well. Recycling may also be employed on a smaller scale within manufacturing facilities for the reclamation of materials and energy lost during processing. Dust collectors or downdraft tables, for example, may collect fine metal shavings lost during metal parts machining; heat exchangers capture the heat energy lost from one process and re-uses it in other processes. Many non-recyclable materials may still be recycled for energy through incineration and waste heat recovery systems.
Useful Recycling Equipment Resources
Sorting & Handling Equipment (Cont.)
Crane Manufacturers Hydraulic Lifts Industrial Loaders Magnets
Vibratory Feeders & Recycling Screens
Size Reduction Equipment
Balers Compactors Pulverizers Shredders
Equipment Used in Recycling
Because material reclamation is seldom performed at receiving and sorting facilities, sorted materials must be baled and compacted into manageable units before they are shipped from sorting facilities to reclamation facilities. Baled materials are often further sorted once they have reached material recovery facilities; bales of polyethylene may be sorted into HDPE and PET, or bales of metal may be sorted into tin, aluminum and steel. Baling and compacting materials for transportation is essential for lowering material transportation costs, as well as for handling within facilities.
Conveyors move plastic bottles, metal scrap, newspaper, cardboard or mixtures of all of these items from receiving stations to sorting stations. Sorting stations are often built in to recycling facility conveyor systems with the help of manual sorting, magnets and non-shearing mixers.
Metal Separator Image Provided by Eriez Manufacturing Co.
Hydraulic power is one of the strongest power sources available, for which reason hydraulic power applications are commonly found in industrial manufacturing and recycling. Metal scrap, cardboard bales, plastic briquettes and other heavy mass quantities of materials are moved from receiving to sorting, from sorting to shredding and/or baling and from baling to reprocessing with the help of hydraulic lifts and hydraulic equipment. The heavy equipment used to transport and load recycling scrap materials typically use hydraulic power; types of lifts may include bulldozers, loaders, scissor lifts, aerial lifts and rotary lifts.
Small amounts of materials which cannot be reclaimed nor disposed of sustainably are usually incinerated. Air pollution control equipment remove volatile organic compounds that may have been released during incineration with fixed bed or fluid bed systems. Heat exchangers are commonly used to reclaim the energy which is released during incineration; this energy may be re-used as thermal heat energy or electricity. This is a process known as waste heat recovery.
A large part of the recycling process involves material handling. Heavy bales and loads of loose materials must be transported to and from sorting and recycling facilities; forklift trucks, overhead cranes and gantry cranes of a variety of sizes and load capacities are used to transport materials to and from collection areas, sorting facilities, recycling facilities and remanufacturing facilities. Grapples and grapple cranes, or loaders, manage large material handling in scrapyards, mines and other outdoor facilities with long, hydraulic arms. Grapple attachments are designed differently depending on what type of scrap material is being handled.
Plastic, paper and cardboard must be mixed and heated with refining chemicals and/or water after shredding in order to be reduced back into raw materials. Large industrial mixers play an important role in this process by refining materials through heating and mixing. Mixers are especially essential for pulp and paper recycling, as all recycled printed papers must undergo a “deinking” process, during which fibers must be mixed and kneaded with chemicals and water for the removal of contaminating inks.
Magnets, magnetic grates and other magnetic assemblies are incorporated into metal recovery systems in order to separate metals from other materials and to separate ferrous metals from non-ferrous metals. This is often called an “induction sorting system”. Rare earth, alnico and ceramic magnets are used in lifting magnets, magnetic sweepers and eddy current separators during sorting processes and for lifting scrap metal bales.
Magnetic Trap and Magnetic Separator Images Provided by Eriez Manufacturing Co.
Size reduction equipment is used between the sorting and refining stages of the recycling process. Once properly sorted by material and, as with glass, by color, materials must be broken down into small fragments to be melted or pulped, refined and remanufactured. Shredders can reduce paper, cardboard, metal and textiles, while grinders and pulverizers handle friable materials such as glass.
Steel holding, mixing and decontaminating chambers are used during the reclamation process of nearly every type of material. As excellent heat conductors, steel tanks and stainless steel tanks are more heat and chemical resistant than plastic tanks, and steel tank manufacturers can fabricate customized capacities and shapes to fit individual facilities.
Vibratory conveyors and feeding troughs are an alternative to belt conveyors and are specifically designed to handle bulk materials. Vibratory conveyors can not only move recyclable materials along towards their destination, but they can also sort and clean through vibration, causing smaller, lighter particles to fall to the bottom. Vibrating screens, trommel screens and rotary trommels may be integrated into conveyor systems as a means of sorting materials.
Recycling Process Diagrams
Waste Heat Recovery