Back to results
US 2026/0233268 A1Published application
Method for the separation and recovery of plastics and contaminants through multi-stage separation process
OwnerThomas A Valerioinventor
Life of this patent
Estimating the term…
Abstract
Methods and systems presented herein are designed for processing waste material to extract plastics. An system and method for separating and recovering plastics from mixed waste feedstock are disclosed. The process involves initial size reduction, moisture removal, and sequential sink-float density separation at different specific gravities to separate low-density plastics such as polypropylene (PP) and polyethylene (PE) from denser materials like acrylonitrile butadiene styrene (ABS) and polystyrene (PS). The system is adaptable to various waste streams and feedstock compositions.
Claims48
A method of separating and recovering materials from a mixed feedstock, the method comprising:
- introducing the mixed feedstock into a first gravity separation system operated at a selected specific gravity to separate a lighter fraction from a heavier fraction;
- removing metal contaminants from the mixed feedstock or from at least one of the lighter fraction and the heavier fraction using a magnetic separation process;
- shredding the lighter fraction to reduce particle size;
- screening the shredded lighter fraction into a plurality of size fractions and discarding fine material below a selected size threshold;
- dewatering a mid-size fraction of the plurality of size fractions;
- separating material from the dewatered mid-size fraction into a plurality of streams based on density differences;
- purifying at least one of the plurality of streams by a secondary separation process that removes fine contaminants;
- mechanically cleaning a selected fraction to remove surface contaminants and unwanted materials;
- and
- recovering a purified material fraction suitable for further processing or recycling.
7 more elements
A method of separating and recovering plastics from a mixed feedstock, the method comprising:
- introducing the mixed feedstock into a gravity separation unit operated at a first specific gravity of about 1.0 to separate a heavier fraction from a lighter plastic fraction;
- passing the lighter plastic fraction through a first screen having a selected opening size configured to liberate fibers and small debris;
- conducting a first sink-float separation at a specific gravity of about 1.0 to separate low-density plastics from denser materials;
- conducting a second sink-float separation at a specific gravity of about 1.15 to refine separation of acrylonitrile butadiene styrene (ABS) and polystyrene (PS) plastics from heavier contaminants;
- processing plastic material through a vacuum pressure separator to separate light, mid-range, and heavy materials;
- and
- applying friction separation to the mid-range materials to remove rubber and foam contaminants.
4 more elements
A system for separating and recovering high-grade plastics from a mixed material feedstock, the system comprising:
- a gravity separation unit operated at a specific gravity of about 1.0 to divide the feedstock into heavier and lighter fractions;
- a screen configured to agitate the lighter fraction and liberate fibers and fine materials;
- a shredder configured to reduce particle size and mechanically clean exterior surfaces of plastic particles;
- a trommel-style screening unit configured to remove small debris, wire particulates, and splinters;
- a first sink-float separation unit operated at a specific gravity of about 1.0 and a second sink-float separation unit operated at a specific gravity of about 1.15;
- a vacuum pressure separator configured to separate light, mid-range, and heavy materials;
- a friction separation device configured to remove rubber and foam contaminants from a mid-range plastic stream;
- and
- an electrostatic sorting system configured to distinguish ABS, PS, and filled PP/PE materials.
6 more elements
A method for recovering plastic material from mixed waste material, comprising:
- receiving a mixed waste feedstock comprising plastic and non-plastic material;
- subjecting the mixed waste feedstock to a first density-based separation stage to produce a first plastic-enriched fraction and a first contaminant-enriched fraction;
- reducing particle size of at least a portion of the first plastic-enriched fraction;
- classifying the reduced material into size fractions;
- conditioning at least one of the size fractions by removing moisture, fines, or both;
- and
- subjecting conditioned material from the at least one size fraction to one or more downstream physical separation stages based on density, aerodynamic response, surface friction, electrical property, or a combination thereof to remove residual contaminants and recover at least one cleaned plastic product fraction.
4 more elements
A system for recovering plastic material from mixed waste material, comprising:
- an input section configured to receive a mixed waste feedstock;
- a first density-based separator configured to separate the feedstock into a first plastic-enriched fraction and a first contaminant-enriched fraction;
- a size-reduction device arranged to receive at least a portion of the first plastic-enriched fraction;
- a size-classification device configured to separate material from the size-reduction device into size fractions;
- a conditioning section configured to remove moisture, fines, or both from at least one of the size fractions;
- and
- one or more downstream separators configured to separate conditioned material from the at least one size fraction based on density, aerodynamic response, surface friction, electrical property, or a combination thereof and to output at least one cleaned plastic product fraction.
4 more elements
Dependencies are inferred from the claim text.