Paper mills and converters produce large quantities of waste paper. Paper trim fromthe process, roll ends, off-quality product and overruns are all sources of waste. Wherefeasible, process scraps are re-pulped and blended back into the feedstock. Converting paperto its final product sometimes produces wastes that are difficult if not impossible to re-pulpwith conventional technology. For example, many paper products are laminated with plastic.Many mills either process laminated waste paper into pellets for boiler fuel or pay to have thewastes land filled. This paper describes a new technology that cost-effectively recoversquality fiber from papers currently being sent to landfill.Fiber Recycling Technologies, Inc. (FRT) has developed a low-energy, mechanicalre-pulping method that gently separates fibers while leaving contaminants largely whole, sothat fiber can be readily screened from contaminants. Trials were run on a range ofrecovered papers and landfill waste, including poly-laminated paper trimmings, multilaminatedfood packaging, and unsorted municipal solid waste. Success from the trialsencouraged FRT to start a commercial re-pulping operation using their own technology. Thisexpanding new business re-pulps high-grade landfill waste papers, creating 18 new jobs.Recovered papers can use considerably less energy in pulping than wood-based pulp,so making secondary fibers competitive with virgin ones can save significant energy. A 20-ton per day FRT pulper now operating commercially annually saves about 7,000 tons ofwaste fiber from being land filled, and requires 11 to 30 kWh per ton for pulping. Bycomparison, refiner-mechanical pulping of virgin wood requires about 1,972 kWh per ton(Martin, N., et al 2000). Other mechanical and kraft pulping processes have similar orgreater energy intensities.
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