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Contamination in compost streams is weighing heavy on processors’ costs, with glass, plastics, and specifically food packaging being among the most burdensome. These and other unwanted materials can be expensive to remove and lower the value of the finished compost product.
“The limitations posed by the need to remove contamination from compost feedstocks is an economic one, not a technical one. A successful composter needs to generate revenue from selling a quality product. Contamination in feedstocks makes that more challenging and increases processing costs,” says Matt Cotton, owner of Integrated Waste Management Consulting.
Removing contaminants early in the process is the biggest challenge. One plastic bag, or one glass bottle, once in the organics stream can become thousands of smaller particles that need to be removed.