Getting Contaminants Out of Your Bales

Getting Contaminants Out of Your Bales

The processing of recyclables has come a long way.

Twenty years ago, the “processing” of recyclables may have consisted of simply dumping a pile of material onto a tip floor and having workers pick through the pile to recover items such as metals and cardboard. Today, the newest recycling centers comprise sophisticated machinery that effectively sorts and separates various recyclables.  

Operators of modern recycling centers need to have keen focus on the quality of the bales of recyclables that are being produced at the facility. To improve the quality of bales, three things are necessary:

  1. Education
  2. Enhancements and adjustments to processing lines
  3. Preservation of quality during storage and transportation


Producing high-quality bales of recyclables starts with a strong education effort aimed at residents. The goal is to get generators to place the “right” material into the right container. A regular review of the inbound material that lands on the tip floor will allow an operator to determine if the educational efforts are sufficient. Too much contamination should trigger an enhanced educational effort to better instruct people how to be good recyclers.

The best educational programs are simple and clear. Importantly, education about recycling needs to be an on-going effort so that you can reinforce good behaviors, change bad recycling habits and ultimately ensure a steady stream of good, inbound material.

In addition to educating residents, it’s equally important to educate drivers and helpers who are collecting the recyclables. Drivers and helpers play a critical role in the recycling process, and they need to use some common sense when placing material into a collection vehicle. Material that is not recyclable should not be delivered to a recycling center.

Processing at the Recycling Center

Good recycling starts with a well-designed and logical process for sorting and separating recyclables. Sorting stations, screens, magnets, optical sorting machines and other equipment must be properly laid out in the proper sequence to allow for the effective recovery of the various commodities. If a system has some design flaws, operators should make the necessary changes to get it right.

A quality assurance/quality control review of the segregated material prior to being fed into a baler is another important step in the process to ensure quality bales.

Another vital function with a modern recycling center is maintenance–making sure all of the equipment is in good working order. With hundreds, even thousands of moving parts, proper maintenance requires a daily commitment. Screens that are clogged and wrapped with plastic bags, wires and strings are not as effective as clean screens; therefore, the screens need to be cleaned daily. Worn-out parts need to be replaced, conveyor belts need to be adjusted and moving parts need to be lubricated–all of which will help make sure the plant is running efficiently.

And remember: Nothing is cheap at a recycling center. Some replacement of parts can cost tens of thousands of dollars, so it’s important to have realistic maintenance expense lines in your budget.

Managers and supervisors should regularly spend time watching every aspect of the recycling process. Carefully evaluating the effectiveness of each piece of equipment and each sorting station will help identify areas that need to be improved. It’s also a good practice to watch the residue line and see what materials are being discarded, thereby allowing you to investigate and make adjustments to stop certain recyclables from ending up in the residue stream.

Inspecting bales is another good practice to look for contamination and analyze moisture content in bales. A manager should periodically break open a bale of final material and carefully comb through the recyclables in search of contaminants. The findings from the bale review process will give you clues on where to improve or change the processing of materials to further eliminate contamination.

Storage and shipping of finished bales

Once a bale of quality material is made, it will most likely be placed in a storage area to await shipment. Bales of recyclables should be stored in a clean and dry area to ensure the material is protected from water and sun damage. An inventory management system should be used to move bales in a timely manner and also to maintain an accurate count of the bales that are in storage and ready for sale.

Finally, the bale storage area should have security systems in place to provide protection from fire and theft.

Shipping material is another component of the recycling process that can cause contamination issues. Forklift operators should do a quick inspection of the trailer that he or she is loading to ensure it is clean, waterproof and free of lingering odors. Dirty, leaking and/or smelly containers and trailers can result in downgrades at the mill due to excessive moisture or poor quality of the bales.

All of these steps will improve the bales that are being pumped out of recycling centers and provide a steady stream of quality recyclables heading to plastic manufacturers, paper mills, metal foundries and other outlets.

Will Flower is president of Green Stream Recycling in Long Island, N.Y. The company is focused on advancing recycling throughout Long Island.

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