Area: Circular Materials · TRL: 3 of 9 (proof of concept on paper; TRL 4 on hold by Amish's instruction) · Stage: P3 · Value-engineering target: USD 25,000 for the equipment (playbook repo, no hardware budget) · Difficulty: 2 of 5
Open playbook for local micro-factories that recover and remanufacture materials safely at small scale: a feasibility matrix by material, process recipes, a micro-factory economics model, safety rules, and a material passport data standard so buyers can trust recycled feedstock. Machines live in their own repos. The guiding principle is to recover and remanufacture locally and export only what needs industrial refining.
Interactive 3D model · Floor plan GA (PDF) · STEM check · Concept options · User requirements · Product requirements · Traceability · Calculation note · Prototype build plan · Design decisions · Concept blueprint (PDF) · Material flow · Review note
Most of the value in collected waste is lost at the first step: scrap is baled and shipped away, or burned to get at the metal. ReflowEconomy starts from the other end. It asks which materials a small team can recover and remanufacture safely with open machines, and which must leave for industrial refining, and it writes the answer down as a playbook: a feasibility matrix, process recipes, an economics model, safety rules and a material passport, all tied to one reference micro-factory that has been sized on paper.
The playbook is open and garage-buildable because the people who would run it are cooperatives and small workshops, not plant operators. The machines are open designs that a local fabricator can build and repair, the layout fits a rented shed of about 60 m², the line runs on a single-phase supply, and the economics model is a CSV file that an operator can change to local prices. Anyone can copy it, adapt it and publish what they learn.
The World Bank estimated 2.01 billion tonnes of municipal solid waste in 2016, rising to about 3.40 billion tonnes by 2050, with the fastest growth in lower-income regions (World Bank, What a Waste 2.0, 2018). Only about 9 % of plastic waste was recycled worldwide in 2019 after losses (OECD, Global Plastics Outlook, 2022).
Where value is recovered, it is often recovered at a cost to health. The world generated 62 million tonnes of e-waste in 2022, and only 22.3 % was documented as formally collected and recycled (ITU and UNITAR, Global E-waste Monitor 2024). WHO reports that up to 12.9 million women work in the informal waste sector, where unsafe recovery can expose workers to lead, mercury and dioxins (WHO, Children and digital dumpsites, 2021).
| Industry | Use |
|---|---|
| Waste-picker cooperatives | Move from selling baled scrap to selling clean flake and products, with a passport that earns a better price |
| Municipal solid waste services | A permittable model for local recovery that reduces open burning and landfill volume |
| Construction and furniture making | Local supply of recycled HDPE and PP sheets and beams of known grade and origin |
| Manufacturers buying recycled feedstock | Clean PET flake with a traceable record and a recycled content statement |
| Metal and e-waste refiners | Correctly identified, packed export lots of metals, boards and cells from small sites |
| Makerspaces and technical schools | A reference layout and recipes for teaching safe small-scale recycling |
| Country or region | Why it matters there |
|---|---|
| Brazil | The National Solid Waste Policy (Law 12.305 of 2010) directs municipalities to prioritize selective collection with waste-picker cooperatives and to fund them (Lei 12.305/2010); a cooperative that also processes keeps more of the value |
| East Asia and Pacific | Higher-income OECD countries have exported plastic waste to lower-income countries in this region for decades (Brooks, Wang and Jambeck, Science Advances, 2018); local processing of their own waste is the alternative to importing others' |
| West Africa (for example Ghana) | Informal e-waste recovery by open burning and acid leaching harms workers and children (WHO, 2021); the playbook's rule is to dismantle and sort locally and export boards and cells to licensed refiners |
| India | The Solid Waste Management Rules, 2016 direct local bodies to recognize organizations of waste pickers, issue identity cards and integrate them into door-to-door collection (MoEFCC, SWM Rules 2016, Rule 15); organized groups of waste pickers could add washing, flaking and pressing on a single-phase supply |
| European Union | Digital product passports under the Ecodesign for Sustainable Products Regulation (EU 2024/1781) will raise the bar for traceable recycled content; a simple open passport helps small recyclers and repair workshops keep up |
The starting point was China's ban on imports of most plastic waste, which took effect in 2018. China had taken in a cumulative 45 % of the world's plastic waste imports since 1992, and Brooks, Wang and Jambeck estimated that about 111 million tonnes of plastic waste would be displaced by 2030 (Science Advances, 2018). The same study found that 89 % of historical exports were polyethylene, polypropylene and PET, the three polymers that small open machines handle best. Countries that had relied on shipping scrap abroad were left holding material they had never learned to process. ReflowEconomy takes that lesson at the smallest useful scale: recover and remanufacture the common polymers locally, and export only what needs industrial refining.
Smaller and lower-income countries export scrap and import finished goods, losing the value of their own materials. Most recycling know-how assumes industrial scale, and unsafe informal recovery (open burning, acid leaching of e-waste) harms workers and communities.
The playbook is built around one reference design: a plastics micro-factory on 59.4 m² (a rented shed, or two 40 ft container footprints where no shed is available) with a central aisle, intake and sorting, washing and float-sink, an enclosed shredder, drying, a hot zone with an extruder and a sheet press under enclosing hoods, a product store, a passport desk and a safety station. Per 100 kg of collected input, the calculation note (RFE-CAL-001) gives on paper 32.3 kg of HDPE and PP products and 19.3 kg of clean PET flake kept local (51.6 %), 10 kg exported for industrial refining (metals, circuit boards, cells), 10 kg of paper sold locally and 28.4 kg to licensed disposal, using 0.88 kWh per kilogram of output. The equipment costs $25,505 (indicative, outside any hardware budget; $505 over the $25,000 value-engineering target), and the site only breaks even at the assumed prices (+$0.17 per shift before rent). Counted as currents, its morning loads draw about 55 A from the 40 A single-phase supply it was designed for, so how a site gets its power is with Amish (three-phase recommended). Keeping disposal at 20 % needs deliveries with about 10 % residue or less, so the playbook adds an intake quality rule. A material passport (schema v0.2) opens at intake and travels with every lot that leaves.
Full design precis: docs/02-concept.md
Every physical, chemical, biological and mathematical claim the micro-factory makes was checked against known science, and a second, independent reviewer tried to refute each verdict (RFE-STM-001). Nothing fails outright. Two details were fixed in the design under Amish's standing instruction: motor energy is now counted at the electrical input (0.88 kWh/kg instead of 0.83), and the shredder's feed slot is 120 mm high so the ISO 13857 reach distance applies to it. One finding goes to Amish: counted as currents rather than kilowatts, the morning loads need more than a 40 A single-phase supply. Air quality and noise can only be confirmed by measurements on a running site.
Two working principles were compared against the user requirements (RFE-OPT-001): A, the reference micro-factory that washes, shreds and melts HDPE and PP into sheets and beams, and B, a sort-and-bale hub that sorts and bales for a regional reprocessor. B scores higher on power, capital and safety; A is the only one that keeps remanufacturing, and its value, local. The recommendation, awaiting Amish, is to keep A as the reference and let a site start as a sort-and-bale hub before it adds the melt line. Both options are modelled in detail in cad/src/model.py.
- Material feasibility matrix: docs/playbook/feasibility-matrix.md
- Process recipes for PET flake, HDPE, PP and aluminium (add-on bay): docs/playbook/recipes/
- Operator-editable economics model per kg and per shift: docs/playbook/economics_model.py with economics_inputs.csv
- Safety and environmental rules: docs/playbook/safety.md
- Reference micro-factory: detailed model cad/src/model.py (container shell and seam fit-out, every machine, panel, rack, fastener and weld; 1,005 parts in option A), floor plan RFE-DWG-001, sizing RFE-CAL-001 and equipment list bom/bom.csv
- Material passport schema v0.2 (JSON): standards/material-passport-v0.2.schema.json, with example records; v0.1 kept at standards/material-passport.schema.json
- Links to machine repos (WasteWise Scan, WasteWise-ml, planned shredder, foundry and cell tester)
The prototype is the reference micro-factory itself, fitted out in a rented shed or in two 40 ft containers joined side by side. The build plan (docs/05-build-plan.md) takes it component by component in build order: the shell and seam beam, the safety station and electrical board, the hot zone with its booth and fume duct, the enclosed shredder and the front row, then racking, desk and the export cage. Eleven parts are made in a local workshop from steel angle, sheet, mesh and plywood, each with its own making sketch; the machines are built to their published open designs or bought. Writing the plan made the layout buildable: the parts added and moved are recorded in RFE-DDR-003, and decisions still open are in the design decisions register.
Chemical refining of metals, battery black mass and e-waste is out of scope for small-scale operations; the playbook limits itself to safe dismantling, sorting, remelting and re-forming.
A micro-factory has moving machinery (shredder), hot surfaces (extruder and press at about 190 to 200 °C), melt fumes, water near electricity, sharp and contaminated input, lithium cells in the waste stream and a high fire load. No open burning, no heating of PVC, fume extraction on every melt process, and a review by a qualified safety professional before any site operates. See the safety section of docs/02-concept.md.
| Folder | Contents |
|---|---|
docs/ |
Problem, STEM check, concept and concept options, user and product requirements, traceability, calculation note (04-calcs/), build plan, design decisions, regulatory, feasibility, risk, market and plan |
docs/playbook/ |
Feasibility matrix, process recipes, economics model, safety |
standards/ |
Material passport schema and examples |
bom/ |
Reference micro-factory equipment list with indicative costs |
cad/src/ |
build123d source of all geometry: model.py (parameters, layout envelopes, the kit 1.9 interface), detail_a.py and detail_b.py (both concept options at D3), detail_common.py and rfe_parts.py (shared builders), drawing sheet (sheets.py), build plan pictures, media and product render scripts |
cad/step/, cad/stl/ |
STEP per made or bought part of option A (cad/step/A/) and an assembly STEP per option; STL of option A (equipment and shell) |
cad/drawings/ |
Floor plan general arrangement RFE-DWG-001 |
media/ |
Concept renders, blueprint, 3D viewer, exploded view and material flow |
build-log/ |
Dated notes |
- wastewise-scan: identify plastic resin type at intake
- WasteWise-ml: image classifier for material class and grade
- Planned: cell tester and grader for battery reuse, plastic shredder, aluminum micro-foundry
| Document | ID |
|---|---|
| Problem statement | RFE-PRB-001 |
| STEM check | RFE-STM-001 |
| Design precis | RFE-PRC-001 |
| Concept options | RFE-OPT-001 |
| User requirements | RFE-URS-001 |
| Product requirements and specifications | RFE-PRS-001 |
| Traceability matrix | RFE-RTM-001 |
| Calculation note | RFE-CAL-001 |
| Prototype build plan | RFE-BLD-001 |
| Design decisions register | RFE-DEC-001 |
| Regulatory and standards register | RFE-REG-001 |
| Feasibility | RFE-FEA-001 |
| Risk register, hazard analysis and design FMEA | RFE-RSK-001 |
| Market and viability | RFE-MKT-001 |
| Project plan | RFE-PLN-001 |
| Decision records | RFE-DDR-001 to 005 |
Pipeline stage: P3 of P0 to P6 (the portfolio cap). Controlled documents follow the portfolio documentation standard. Each carries a document ID, a version and a revision history. Branded PDFs are built with python .kit/render.py; run python .kit/render.py --check to validate them.
Designed by Amish Chadha. See CONTRIBUTORS.md for roles. To cite this design, use CITATION.cff (GitHub shows it as "Cite this repository").
AI assistance (Claude) was used to accelerate concept renders, prototype documentation and first-pass sizing calculations. Design direction and all decisions are Amish Chadha's, recorded in this repository's decision records (docs/decisions/).
- Hardware (CAD, drawings, BOM, electronics): CERN-OHL-S v2
- Software (firmware, scripts, notebooks): MIT
- Documents: from the first tagged release, the playbook text moves to CC BY-SA 4.0 (RFE-DDR-002). Until then the licenses above apply.
A project of the Design Molecule lab.