Intent:
To mitigate post-sorting contamination or residue rates for the successful recirculation of recovered materials
Requirements:
Demonstrate that material recovery facilities (MRFs) operated by the municipality, or operated by companies contracted by the municipality, or operated by companies subcontracted by franchise haulers, achieve the following post-sorting contamination/residue rates:
Mixed Waste MRFs
Tier 1: Achieve post sorting contamination/residue rates below 10%
Tier 2: Achieve post sorting contamination/residue rates below 5%
Tier 3: Achieve post sorting contamination/residue rates below 3%
Paper/Paperboard <10% Moisture | Metal | “MRF Glass” | Plastic Bale Contamination | |
Tier 1 | Outhrows + Prohibited 90% of maximum allowed for each grade | 90% of maximum allowed for each grade | Non-glass residue & Fines < 10% |
|
Tier 2 | 70% of maximum | 70% of maximum | <7% |
|
Tier 3 | 50% of maximum | 50% of maximum | <4% |
|
Single Stream MRFs
Tier 1: Achieve post sorting contamination/residue rates below 5%
Tier 2: Achieve post sorting contamination/residue rates below 3%
Tier 3: Achieve post sorting contamination/residue rates below 1%
Paper/Paperboard <10% Moisture | Metal | “MRF Glass” | Plastic Bale Contamination | |
Tier 1 | Outhrows + Prohibited: 80% of maximum allowed for each grade | 80% of maximum allowed for each grade | Non-glass residue & Fines < 7% |
|
Tier 2 | 60% of maximum | 60% of maximum | <5% |
|
| Tier 3 | 40% of maximum | 40% of maximum | <3% |
|
Dual Stream MRFs
Tier 1: Achieve post sorting contamination/residue rates below 3%
Tier 2: Achieve post sorting contamination/residue rates below 2%
Tier 3: Achieve post sorting contamination/residue rates below 1%
Paper/Paperboard <10% Moisture | Metal | “MRF Glass” | Plastic Bale Contamination | |
| Tier 1 | Outhrows + Prohibited: 60% of maximum allowed for each grade | 70% of maximum allowed for each grade | Non-glass residue & Fines < 6% |
|
| Tier 2 | 50% of maximum | 50% of maximum | <4% |
|
| Tier 3 | 30% of maximum | 30% of maximum | <2% |
|
Potential Strategies:
- Utilize contamination/residue rate calculation methodology in SWEEP Certification Manual
- Material grading of inbound material
- Inbound volume metric collection (for calculation)
- Sorting on the tipping floor
- Metering drums and conveyor speeds
- Film removal (vacuum)
- Manual sorting (pick line)
- Density sorting technology (ballistic separators, conventional disc screening, etc.)
- 2-D vs. 3-D sort
- Eddy Current (Aluminum)
- Magnets (Ferrous and other metals)
- Optical sorting (glass by colors, plastics by types, etc.)
- Sorted stream metrics collection
- Residual metrics collection
Note that contamination rates are determined by visual “Counts of Contamination” where both the amount and variety of contaminants is factored in.
Clarify this is for bale quality, not inbound quality.
There is a wide variety of specs by end material type. May need to qualify this by materials.
Instead, implement a Tier 1, 2, 3 matrix that shows the bale contamination rates by material by type of MRF