Materials recovery facility
A materials recovery facility, materials reclamation facility, materials recycling facility or Multi re-use facility (MRF - pronounced "murf") is a specialized plant that receives, separates and prepares recyclable materials for marketing to end-user manufacturers. Generally, there are two different types: clean and dirty MRFs.
A clean MRF accepts recyclable commingled materials that have already been separated at the source from municipal solid waste generated by either residential or commercial sources. There are a variety of clean MRFs. The most common are single stream where all recyclable material is mixed, or dual stream MRFs, where source-separated recyclables are delivered in a mixed container stream (typically glass, ferrous metal, aluminum and other non-ferrous metals, PET [No.1] and HDPE [No.2] plastics) and a mixed paper stream (including OCC, ONP, OMG, Office packs, junk mail, etc.). Material is sorted to specifications, then baled, shredded, crushed, compacted, or otherwise prepared for shipment to market.
A dirty MRF accepts a mixed solid waste stream and then proceeds to separate out designated recyclable materials through a combination of manual and mechanical sorting. The sorted recyclable materials may undergo further processing required to meet technical specifications established by end-markets while the balance of the mixed waste stream is sent to a disposal facility such as a landfill.
The percentage of residuals (unrecoverable recyclable or non-program materials) from a properly operated clean MRF supported by an effective public outreach and education program should not exceed 10% by weight of the total delivered stream and in many cases it can be significantly below 5%. A dirty MRF recovers between 5% and 45% of the incoming material as recyclables, then the remainder is landfilled or otherwise disposed. A dirty MRF can be capable of higher recovery rates than a clean MRF, since it ensures that 100% of the waste stream is subjected to the sorting process, and can target a greater number of materials for recovery than can usually be accommodated by sorting at the source. However, the dirty MRF process is necessarily labor-intensive, and a facility that accepts mixed solid waste is usually more challenging and more expensive to site.
New mechanical biological treatment technologies are now beginning to utilise wet MRFs. This combines a dirty MRF with water, which acts to densify, separate and clean the output streams. It also hydrocrushes and dissolves biodegradable organics in solution to make them suitable for anaerobic digestion.
- ArrowBio Process Finstein, M. S., Zadik, Y., Marshall, A. T. & Brody, D. (2004) The ArrowBio Process for Mixed Municipal Solid Waste – Responses to “Requests for Information”, Proceedings for Biodegradable and Residual Waste Management, Proceedings. (Eds. E. K. Papadimitriou & E. I. Stentiford), Technology and Service Providers Forum, p. 407-413
- Mastermind of the MRF Logsdon, Gene. BioCycle. Emmaus: Apr 1993. Vol. 34, Iss. 4; pg. 49, ff. 
- Typical commercial recycling plant with information about recycling methods
- "Coming soon! van der Linde's amazing recycling machine"