Municipal Solid Waste (MSW) Shredders

Yes. WEIMA builds shredders specifically designed for heterogeneous household and municipal waste streams that contain plastics, paper, textiles, wood, organics, and occasional metals. Twin-shaft pre-shredders such as the M8.28 are ideal for opening bulky items and handling irregular infeed, while single-shaft machines like the PreCut and PowerLine produce a stable output for sorting or RDF production. Optional wear protection packages and hydraulic drives help maintain performance even when stones or metal pieces are present. Additional metal separation units can be integrated to protect the cutting system and improve output quality.

Your choice depends on incoming material condition and the desired output size. For bulky, compacted, or highly mixed MSW, a pre-shredder such as the M8.28 or PreCut 2000 provides the first size reduction and stabilizes material flow. For defined particle sizes — especially for RDF — a single-shaft machine like the PowerLine 2500 or 3000 is typically used in a secondary stage. If the waste stream is already uniform, a single-shaft shredder may be sufficient in one pass. WEIMA engineers can match cutting geometry, screen size, and drive configuration to your exact requirements.

Many MSW facilities use a two-stage system for optimal results, but a single machine may be sufficient for simpler goals. A common configuration uses a pre-shredder (M8.28 or PreCut 2000) to open bags and break down bulky items, followed by a PowerLine unit as a secondary shredder to achieve the desired RDF or sorting fraction. If your goal is basic volume reduction or coarse output, one shredder may meet your needs. The right design depends on contamination, feed variability, and downstream equipment requirements.

After the initial shredding, the material passes through screening and separation steps to refine it into a consistent fuel stream. Lines commonly separate fines and coarse fractions, remove metals using magnetic systems, and apply air or optical sorting to eliminate inert materials. The coarse fraction — typically containing films, paper, rigid plastics, and wood — is preferred for RDF because of its higher calorific value. Typical values range from 10–15 MJ/kg, depending on composition. These steps help ensure stable performance in RDF combustion and co-processing systems.

They create a consistent, predictable particle size, which is essential for fuel preparation. When material is pre-shredded and then sized with a single-shaft shredder, downstream systems can remove fines, metals, and inerts more effectively. Uniform particle size improves mixing, drying, dosing, and combustion stability in RDF plants. The PowerLine 2500 and 3000 are commonly used as secondary shredders to refine output for fuel production.

Yes — WEIMA shredders are designed for the harsh conditions of mixed MSW, but pre- and post-shred metal separation is still strongly recommended. Municipal waste often contains stones, screws, bolts, and other contaminants that can increase wear. WEIMA uses heavy-duty rotors, hydraulic drives, and optional Vautid or Creusabro wear liners to manage abrasive loads. Adding magnets, eddy current separators, and protective screens around the shredder helps remove unwanted items and extend machine life.

The final particle size depends on the screen, the rotor type, and the moisture level of the material. PowerLine single-shaft shredders use interchangeable screens that allow operators to target the exact output needed. In RDF applications, these machines often serve as secondary shredders to produce a refined, uniform fuel fraction. A WEIMA specialist can recommend the ideal configuration after testing your specific MSW sample. Fine-tuning screen size ensures your output meets downstream specifications.

Expect regular wear checks, knife inspections, and scheduled service to maintain high uptime. Daily tasks often include cleaning the cutting chamber and visually inspecting knives and counter-knives. Routine service involves rotating or replacing knives, adjusting the cutting gap, checking hydraulic filters, and monitoring wear liners. These liners protect high-impact zones and can be replaced during planned maintenance stops. WEIMA machines are designed for straightforward access to minimize downtime during service.

A hydraulic drive provides high torque, smooth starts, and excellent load management. It can start, stop, and reverse under heavy load, which is valuable when processing mixed MSW where density and contaminants vary constantly. The system absorbs shocks from heavy or unexpected materials, helping protect the rotor and knives. WEIMA uses Hägglunds Bosch Rexroth hydraulic systems on models like the PreCut and PowerLine to ensure consistent, reliable operation.

Allocate space for safe feeding, discharge conveyors, service access, and dust control. These machines are large — some models have working widths of up to three meters — so consider layout for infeed and discharge belts, magnets, screens, and ventilation. Leave clear maintenance zones for knife changes and hydraulic access. WEIMA can integrate shredders into existing MSW lines or design complete upstream and downstream components to match your facility.