Tyre pyrolysis and gasification technologies
Guide developed by ARUP and Rawtec, authorised and published by Tyre Stewardship Australia with Sustainability Victoria and the Department of Environment and Science. June 2018. The original is on the Tyre Stewardship Australia website.
Summary published
Australians discard about 56 million equivalent passenger tyres a year, 450,000 tonnes of them. Pyrolysis is regularly proposed as the answer. This guide tests that proposal. Its central finding:
“The authors are aware of no long term — that is, more than five years in operation — financially viable plants, anywhere in the world.” And on the pitch itself: claims that pyrolysis will solve large stockpile issues and that it is a well-established commercial practice “are currently unjustified and should be met with caution”.
The guide provides three question sets — one for government, one for funders, one for proponents.
Equivalent passenger tyres discarded annually in Australia
Annual end-of-life tyre tonnage
Plants worldwide financially viable beyond five years
R&D time European operators needed
What the evidence shows
Product mix, staffing and maintenance costs
Yields are about 45% oil, 30% char, 15% scrap steel and 10% syngas. Recovered carbon black spans AU$200 to about AU$3,000 a tonne, with roughly $900 to $1,000 needed for overseas sale. Unrefined oil fetches about AU$140 a tonne against up to AU$1,200 refined. Viability depends on refinement and carbon black quality.
10 to 20 full time staff for every 10,000 tonnes received per year, and “annual repair and maintenance costs should be factored at around 10% of the capital investment”. Capital runs from AU$1.5 million to AU$40 million depending on scale.Time to commercial scale, and how much capacity exists
Pyrolyx took 11 years of R&D, Black Bear Carbon seven, and the European plants generally 10 to 15. Pearl Global in Queensland has five. The guide’s assessment: “Australia remains five to 10 years behind Europe”.
Reklaim in Oregon opened in 2008 and closed in 2016 “due to excessive cost in transport of materials to markets”.
As at April 2018: two in NSW, three in Queensland, one in Tasmania, two in Victoria, two in Western Australia, zero in South Australia and the Northern Territory — against 450,000 tonnes a year of feedstock.
The largest Australian capacity named is Pearl Global at 10,000 tonnes a year rising to 20,000. Internationally, Scandinavian Enviro Systems runs about 27,000 and Pyrolyx’s Indiana plant 40,000 at AU$40 million. Combined, the plants in the set are well short of Australia’s annual arisings.
The evidence base, and pyrolysis versus gasification
“Much of the available information on the technology is provided by, or associated with, the proponents of the technology.” The guide flags its own evidence base as the core difficulty in assessing these projects.
Pyrolysis runs at 400 to 1,200°C in the absence of oxygen; gasification at 700 to 1,400°C with limited oxygen. Different end product mixes — and the guide warns government readers to watch for “technology rebranding that disguises pyrolysis”.
The three question sets
Demand evidence of secured end markets before approval. Examine full system costs including transport, gate fees, preparation and stockpiling. Scrutinise below-market gate rates. Restrict tyre accumulation without processing. Watch for rebranded pyrolysis.
Prioritise research and development funding over full-scale operations. Avoid funding stockpile remediation via pyrolysis when proven alternatives exist. Require controls demonstrating output quality. Verify end-market commitments and actual buyer prices. Expect multi-year returns.
Quality-assured feedstock at competitive gate rates. Partnerships with collectors and shredders. Product quality that meets market specifications. Verified current and projected selling prices. And understand preparation costs, which the gate fee does not cover.
The guide is “general only and is not intended to argue the case for or against the construction of tyre pyrolysis plants”, and is “not intended to be used as a sole decision-making tool”. Its case study plants are “demonstrations only” and the authors “do not sponsor, endorse or necessarily approve” them. The international plant table “does not include all tyre pyrolysis plants in operation globally” and “the commercial viability of these plants is unknown”. It reflects a point in time in June 2018 and recommends readers undertake further research, including the companion independent technology review.
Related work
Other technology and materials market assessments.
The full guide includes the state-by-state regulatory table, the Australian and international plant tables and all three stakeholder question sets.
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