Stadler, based in Altshausen, Germany, designed and built a dry-mixed recyclables sorting plant in Hartlepool, UK, for J&B Recycling in 2008 and has since supported the company in continuous improvement of the factory.
“We are continually improving the plant and our goal is to produce the best material possible,” says Matt Tyrie, Operations Manager at J&B recycling.
The composition and density of the material flow is constantly changing. “Over the years, the amount of cardboard has increased significantly,” says Benjamin Eule, director of Stadler UK Ltd. “Sorting centers receive greater volumes of packaging generated by the growth of online purchases and deliveries. Another impactful change is the shift to different printing techniques in magazines, which makes it more difficult to separate the ink from the fiber. Plastic packaging is also changing, with multilayers and bottles with different types of sleeves, making detection increasingly difficult. Metals have also evolved since the plant was designed in 2008, with the switch from aluminum to ferrous metal in beverage packaging and increased volumes of aluminum-containing coffee capsules.
For this reason, sorting plants must be able to process multiple materials flexibly while delivering the consistently high purity levels demanded by the recycling industry, Stadler says. Plant designs must also be flexible enough to accommodate future upgrades and modifications to meet changing requirements.
Eule says, “The J&B Recycling plant was originally designed to process 12 [metric tons per] hour, with Stadler trommel screens, conveyors and a ballistic separator supporting mechanical pre-sorting, preparing the material flow for efficient downstream processing. Conveyors ensure that material is efficiently sent to the next sorting process and hopper storage conveyors hold product before it is baled. »
In 2017, J&B Recycling and Stadler worked together on a concept to eliminate paper and aluminum, adding a Tomra Autosort optical sorter and an eddy current separator.
Since then, six additional upgrades have further optimized the plant to meet changing market demands. The latest upgrade, completed in March, aimed to achieve even higher paper purity and increase capacity to 15 metric tons per hour.
“We have installed another optical sorter, the latest Autosort sorter, to remove film, plastic bottles and cardboard from the PAMS fraction (newspapers, periodicals and magazines) to obtain paper with a purity of 95 %”, explains Eule. “We recirculate the materials that we have removed in the plant to be reprocessed in their respective streams, thereby increasing plant recovery.”
“The upgrade achieved the goals we set out to improve quality, reduce labor costs and increase throughput,” says Matt Tyrie, operations manager at J&B Recycling. “We have improved the quality of our hard mix grade by adding a laser object detection (LOD) system to the Autosort optical sorter to remove more non-fibrous contamination. This technology allows each shift to operate with reduced labor and has allowed for increased throughput, as hard mix quality was a bottleneck for the plant.
“In all the years we’ve worked with Stadler, their product quality and ability to meet installation deadlines stand out,” adds Tyrie. “We really appreciate the excellent planning of the projects and their ability to bring ideas and designs to fruition.”
A metering drum feeds the material, which passes through a pre-sorting platform for manual disposal of old corrugated containers (OCC) and large films. A Stadler screen drum separates the remaining material into three fractions: fine, medium and oversized.
Oversized materials, measuring more than 170 millimeters, or 7 inches, pass through a quality control booth and Autosort to remove paper, cardboard and mixed plastics and produce a PAMS fraction.
The medium size fraction, less than 17 millimeters or 7 inches, is separated into fine, 2D and 3D fractions by the Stadler STT2000 ballistic separator. The flat 2D fraction is processed through eddy current separators and an Autosort optical sorter before final quality control to produce two streams: mixed paper and metals. 3D lamination fractions follow a similar process, which begins with an overband magnet, to produce mixed fractions of plastic, high density polyethylene and polyethylene terephthalate. The fines are processed to remove contaminants to create a glass product. All output fractions except glass are baled and sold, according to Stalder.