Republic Services is tackling head-on the crisis of overly contaminated waste streams in today’s MRFs. With current residential contamination levels reaching as high as 30% or more, it is critical that processors send a clear message to the community about what is accepted in the recycling program, while also employing the most advanced, flexible technology on the market to separate this evolving stream.
The company’s Plano, TX facility, which opened in April 2019, has put community education at the forefront. A 5,000 square foot Learning Center features interactive games aimed to educate the public on what materials are properly recyclable, as well as an observation deck overlooking the 77,000 square foot recycling facility itself. A video campaign called Recycling Simplified breaks down recycling into simple steps with easily remembered tips, such as common items that do or don’t belong in the bin, and to never bag items in plastic film.
An engaged approach toward the community helps eliminate some common and problematic habits that residents can have when it comes to their curbside bin. Phenomena like “wishcycling” (a misguided hope that the recycling facility will know what to do with questionable items) are discouraged with the simple phrase “when in doubt, throw it out.” A popular industry webinar from last year addressed the destructive impact of consumer behaviors that arise when the public is not provided with a clear and united message. Republic Plano works to solve part of the problem that begins with community guidance.
When it comes to dealing with the material the plant does receive, which serves more than 510,000 residents and 2,500 commercial customers throughout the Dallas-Fort Worth metro area, Republic takes a unique approach with the technology on its sorting line. Equipment that makes intelligent sorting decisions with high degree of flexibility prepares the facility for the future.
To achieve extremely high recovery of all mix paper that is clean and sellable with minimal QC sorting, Republic uses equipment supplied by Van Dyk Recycling Solutions, along with the supplier’s “Positive Sorting” method. The unique method uses a combination of non-wrapping screens and optical sorters to intelligently separate and improve the quality of the fiber recovered from the stream. Optical units shoot positively on paper at the front end by identifying its material characteristics and positively separating it from the stream. Traditional methods of removing contaminants from paper based on size, shape, and density create too much collateral damage for today’s high purity standards. With a higher purity fiber stream headed to quality control, the plant will need fewer manual sorters to remove nonfibrous materials.
To prepare the material for positive sorting (optical units perform best when the material is properly pre-sorted and evenly spread on the belt), a non-wrapping ONP screen separates paper from containers. Traditional inclining screens meant to do the same job are notorious for getting so clogged with plastic films and other contaminants that everything goes up and over the screen and separation ceases to occur. Severely clogged screens are known to take well over an hour to clean after each shift. Stars take a beating and need to be replaced frequently.
Van Dyk’s non-wrapping screen has a larger shaft with specially shaped and spaced stars. Because of this design, it incurs virtually no film wrapping and continues to separate materials at peak ability for an entire shift at full capacity. Reportedly the screen takes as little as ten minutes to clean. And because the screen has larger and fewer stars, the need for replacement parts is significantly reduced.
This non-wrapping screen to optical setup gives Republic’s facility an unprecedented degree of flexibility. With the ever-evolving ton, many facilities are constantly facing changes in their stream’s composition, which brings new challenges. Traditional screening approaches struggle to adapt to a changing stream and will continue to produce degrading fiber quality and require high maintenance costs. But having multiple sensor optical sorting units on primary separation prepares a plant for the future. The optical units can be reprogrammed on the spot to recognize and recover a different commodity, should the incoming stream undergo drastic changes. There are also 4 separate fiber storage bunkers to make OCC and 3 different grades of mix paper that can be baled separately or blended.
The design incorporates a mono-platform and second-level system access, which allows sorting personnel to safely access all QC lines on a central platform, without walking on the operating floor. The system also features an elliptical screen for film removal, another series of optical sorters to separate plastics, a system-wide dust collection network, and a glass cleanup system proven to recover over 95% of clean glass via a specialized vibratory screen and density separator. A Bollegraaf HBC-120S baler is intended for baling fiber and OCC, but is capable of baling all commodities for full baler redundancy.