VOL. MMXXVI · NO. 0319 A LIVING ENCYCLOPEDIA OF MATERIAL CYCLES PRICE: 0¢ · OPEN ACCESS

recycle.wiki

Wednesday, the 19th of March, MMXXVI · Edition Perpetual « Nihil Perdetur, Omnia Mutabuntur »
Filed under — Polymers

The Long Memory of Plastic

A polyethylene terephthalate molecule, once chained, remembers its origin in petroleum for centuries. Yet under the right thermal pressure it forgets, and remembers again as fibre, as bottle, as fleece.

By the Materials Desk

Lead Article — The Closed Loop

Why Aluminium Never Truly Dies, Only Sleeps Between Lives

A single aluminium can, melted and recast, returns to the supply chain in roughly sixty days—losing only a sliver of mass to oxidation. The metal that wrapped your soup at noon may seal a window-frame by autumn. This is the secret economy of materials: not consumption, but circulation.

In smelters from Reykjavik to Reykjanes, the same atoms have circulated for a century. To recycle is not to discard with conscience—it is to participate in a metabolism older than the city, slower than the river, more patient than the stone.

By the Editorial Board · with diagrams from the Plate Room

Filed under — Glass

The Furnace and the Cullet

Crushed glass, called cullet by the trade, lowers the melting point of fresh batches by a measurable margin—saving energy with each reincarnation of the bottle.

By the Mineral Desk

§ The motto, in clumsy Latin, intends: Nothing shall be lost, all shall be transformed.

Section II

The Knowledge Grid

A taxonomy of materials, processes, and the persons who attend them. Read in any order; cross-references are provided where the matter benefits from another angle.

No. 01 · Polymers

Polyethylene Terephthalate

A condensation polymer of terephthalic acid and ethylene glycol, prized for its clarity, dimensional stability, and willingness to be re-extruded. Its recycling code is the numeral 1 within the chasing arrows—a glyph more recognised than most national flags.

The polymer recovers nearly its original molecular weight after solid-state polymerisation, permitting bottle-to-bottle circuits indefinitely—in theory. In practice, dye contamination and adhesive residue limit the count to between five and seven turns of the loop.

No. 02 · Process

Optical Sortation

Near-infrared spectroscopy reads the molecular signature of each fragment as it passes a sensor; a precise puff of compressed air diverts the fragment into the correct bin. The sorter never tires, never blinks, and works at five tonnes per hour.

“A puff of air, calibrated to a milligram, decides whether the bottle becomes a bottle again or a fibre for fleece.”
No. 03 · Mineral

Cullet

Crushed glass intended for remelt. Each ten-percent addition of cullet to a furnace charge reduces energy consumption by approximately three percent—a small economy that compounds across the gigatonnes of glass produced annually.

No. 04 · Metal

Aluminium

Recycling expends roughly five percent of the energy required to smelt the metal from bauxite ore. The numerical asymmetry is the most persuasive argument the metal has ever made for itself.

cf. Hall–Héroult process, 1886.

No. 05 · Fibre

Pulp

A paper fibre survives between five and seven recyclings before its cellulose chains shorten beyond the threshold of useful tensile strength. After that, it is composted, burned, or buried.

No. 06 · Practice

Rinsing

A trivial domestic gesture with disproportionate downstream consequence: a clean container does not contaminate its bale, does not earn its lot a penalty at the buy-back, does not become landfill by association.

No. 07 · Concept

Embodied Energy

The cumulative energy invested in extracting, refining, transporting, and forming a material. To recycle is, more than anything else, to preserve embodied energy from oblivion.

No. 08 · Apparatus

The Materials Recovery Facility

A cathedral of conveyors. Mixed recyclables enter at one end and emerge at the other as graded bales of paper, cardboard, aluminium, steel, PET, and HDPE—each bale a future commodity, each transition mediated by trommels, eddy currents, magnets, optical readers, and the practiced hands of human pickers at the quality-control line.

“The facility does not destroy waste. It un-mixes it. The unmixing is the work.”

The throughput is measured in tonnes per hour; the residue—everything that cannot be sold to a remanufacturer—is measured in shame. A well-run facility recovers ninety-three percent of inbound mass; a poorly-run one, sixty-eight.

No. 09 · Chemistry

Glycolysis of PET

A depolymerisation pathway: ethylene glycol, applied at temperature, cleaves the polymer into its monomeric subunits, which can then be filtered, decoloured, and re-polymerised into virgin-grade resin—the rare second chance at being unblemished.

No. 10 · Term

Down-cycling

A recycling event that produces a material of inferior grade to its predecessor: a clear bottle becoming an opaque fibre, a sheet of writing paper becoming a corrugated liner. The arrow turns, but it does not close.

No. 11 · Term

Up-cycling

A recycling event that produces a material of superior grade or value, ordinarily by chemical refinement or design intervention. A rare event in industrial volume; a common event in studio practice.

No. 12 · Concept

The Loop

A closure not of geometry but of accounting. The loop closes when the output of the recycler equals the input of the manufacturer—not approximately, but precisely, in mass, in chemistry, in fitness for purpose.

No. 13 · Practice

Source Separation

The discipline of dividing waste at its origin—in the kitchen, the office, the factory floor—into streams compatible with the downstream apparatus. The first separation is the cheapest; every separation thereafter is paid for in capital and dignity.

Section III · Plate the First

The Anatomy of a Single Recycled Bottle

An illustration of the journey from discarded vessel to reborn vessel, annotated for the patient reader.

Pl. I. — The cycle of a single PET bottle, demonstrating the six stations of its journey: (1) the discarded vessel, recovered at kerb or container; (2) the optical sorter, which separates clear from coloured by spectroscopy; (3) the shredder, reducing the vessel to flake; (4) the glycolysis reactor, depolymerising the flake into monomer; (5) the extruder, which spins fresh pellets; (6) the new vessel, bottled and labelled, indistinguishable from virgin stock.

Section IV

The Index

A compressed lexicon of terms, persons, processes, and apparatus referred to throughout the gazette. Cross-references appear in small caps; page numbers are notional.

  1. Anaerobic digestionMicrobial decomposition of organic matter without oxygen, yielding biogas. see Methane.
  2. BauxiteSedimentary rock; principal ore of aluminium. cf. Hall–Héroult.
  3. BaleA compressed bundle of sorted material, the unit of trade between facility and remanufacturer.
  4. CellulosePolysaccharide; structural fibre of paper. Recyclable five to seven times.
  5. CulletCrushed glass for furnace remelt. see Glass.
  6. DepolymerisationChemical reduction of a polymer to its monomers. see Glycolysis.
  7. Down-cyclingA recycling event yielding inferior material grade.
  8. Eddy current separatorApparatus inducing a magnetic field to repel non-ferrous metals onto a separate stream.
  9. Embodied energyCumulative energy invested in a material's manufacture.
  10. Extended producer responsibilityPolicy doctrine requiring manufacturers to fund the end-of-life of their products.
  11. Ferrous metalIron-bearing alloys, separable by magnet.
  12. FlakeSmall fragments of plastic post-shredding, awaiting wash and remelt.
  13. GlycolysisSolvolysis of PET by ethylene glycol. A pathway to virgin-grade resin.
  14. Hall–HéroultElectrolytic process for primary aluminium production, 1886.
  15. HDPEHigh-density polyethylene; recycling code 2.
  16. Iron gall inkA historical ink of tannic and ferrous compounds, mentioned for the palette only.
  17. Kerbside collectionMunicipal scheme of source-separated household pickup.
  18. Loop, the closedAn accounting equality of recycled output to manufacturer input.
  19. Materials Recovery FacilityIndustrial cathedral of conveyors. Abbr. MRF.
  20. MethaneCH₄; principal yield of anaerobic digestion. A fuel and a hazard.
  21. Near-infraredSpectral band 700–2500 nm, used in optical sortation.
  22. Optical sorterApparatus separating fragments by NIR spectroscopy and air jet.
  23. PETPolyethylene terephthalate; recycling code 1. see Polymers.
  24. PolymerA long-chain molecule of repeating units; thermoplastic if remeltable.
  25. PulpSlurry of cellulose fibres; the matrix of recycled paper.
  26. Recycling codeNumeral within chasing arrows; identifies polymer family. 1–7.
  27. RemanufacturerBuyer of bales; converter of recovered material into new product.
  28. ResidueThe mass that escapes recovery and proceeds to landfill or incinerator.
  29. Solid-state polymerisationProcess restoring molecular weight to recycled PET. Abbr. SSP.
  30. Source separationDivision of waste at origin, prior to collection.
  31. Tetra PakComposite carton of paper, polyethylene, and aluminium. Recoverable, with effort.
  32. ThermoplasticA polymer family that softens upon heating and is therefore recyclable in principle.
  33. TrommelRotating cylindrical sieve; first apparatus on most MRF lines.
  34. Up-cyclingA recycling event yielding superior grade or value.
  35. Virgin resinPolymer freshly synthesised from feedstock. The benchmark of grade.
  36. WishcyclingThe hopeful, incorrect placement of non-recyclable items in the bin. A tax on the system.
  37. Zinc-plated steelGalvanised stock; recovered as ferrous via magnet, dezincified at the smelter.
Colophon

Set in cold type, printed in patient ink.

This gazette is composed of Playfair Display for its headlines, Libre Baskerville for its body, and IBM Plex Sans for its quieter labours. It is printed in Ink Black on Newsprint Cream, ruled in Column Rule Gray, and stamped, where necessary, in Archival Gold. No sentence has been written that did not need to be written; no rule drawn that did not need to divide.

Every material on Earth wishes to be neither used up nor thrown away, but to circulate—through fire, through reagent, through the practiced hands of the sorter—back into the next vessel that wants its body. We exist to record that wish, faithfully, and to give it a small library of its own.

— The Editors, Wednesday last — ❦

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