How much fossil carbon do the Intergovernmental Panel on Climate Change defaults give for rubber scrap or waste tyres that are burnt?

The Intergovernmental Panel on Climate Change (IPCC) 2006 guide has two rubber rows that agree on total carbon, about 0.56 tonne per tonne burnt, but split it differently: 20 percent fossil in the municipal table and 17 of 56 in the industrial one. A tonne gives 0.41 or 0.62 tonnes of fossil carbon dioxide (CO2).

The two rubber rows

• Table 2.4, municipal solid waste components, "Rubber and Leather": dry matter 84 percent of wet weight, total carbon 67 percent of dry weight, fossil carbon fraction 20 percent of the carbon.
• Table 2.5, industrial process waste, in percent of wet waste: "Rubber" has total carbon 56, fossil carbon 17 and water content 16. The degradable carbon figure of 39 is in brackets with a note that natural rubber would likely not degrade under anaerobic conditions at a dump.
• The guide's text adds that a certain amount of tire waste is also considered a source of fossil carbon, since tires can be composed of synthetic rubbers or carbon black.

They agree on carbon and differ on its origin

Table 2.4 works out to 0.84 x 0.67 = 0.563 tonne of carbon per tonne of wet rubber, of which 20 percent is fossil. Table 2.5 gives 0.56 tonne, of which 17 is fossil, so 30 percent of the carbon. The totals match. The fossil share is 30 percent in Table 2.5 against 20 in Table 2.4.

The rest of the carbon is non-fossil; the guide does not call it biogenic for rubber, so do not treat it as biomass without a source. For national inventories the guide says CO2 from biomass material in waste should not be included in national total estimates. How a company reports it depends on the reporting standard it follows.

Using them for a rubber unit

Our reading: vulcanised offcuts, flash and trimmings are process waste from a rubber industry, so the Table 2.5 row fits by wording, and Table 2.4 is a municipal waste line (rubber and leather). Neither knows your compound. The Pune rubber cluster profile says natural rubber is 25 to 40 percent of raw material consumption, the other main inputs being synthetic rubbers such as nitrile, styrene butadiene, butyl and EPDM (ethylene propylene diene monomer), plus curing, protective and reinforcing agents. A compound heavy in synthetic rubber can hold a different fossil share from either default. If your compounding sheet gives the natural and synthetic shares, use it.

The tyre-derived fuel page already says to ask the fuel supplier or a laboratory for the fossil fraction. These defaults are the fallback when neither answers.

50 tonnes of cured rubber scrap burnt in a year (example quantity)

• Table 2.4: 50,000 kg x 0.84 x 0.67 x 0.20 x 1.0 x 44/12 = 20,636 kg, 20.6 t of fossil CO2
• Table 2.5: 50,000 kg x 0.17 x 44/12 = 31,167 kg, 31.2 t of fossil CO2
• Gap: 10.5 t, with Table 2.5 about 51 percent higher
• Non-fossil carbon in the same burn: Table 2.4 22,512 kg of carbon, 82.5 t of CO2; Table 2.5 19,500 kg, 71.5 t of CO2

Quantity is an example. Oxidation is taken as 1.0, the incineration value in Table 5.2.

What Senseible does here

Senseible reads fuel invoices and electricity bills into dated, fingerprinted records, so your kilowatt-hours and litres are on file by date. It does not measure scrap carbon content. Your scrap register and compound sheet are the inputs.

• Tyre-derived fuel: biogenic share
• CO2 from incinerating waste
• Moulded rubber part CO2 per kg
• Waste tyre rules and the tyre footprint
• Your MSME carbon number

Sources: IPCC 2006 Guidelines, Volume 5, Chapter 2: Waste data (Tables 2.4 and 2.5), IPCC 2006 Guidelines, Volume 5, Chapter 5: Incineration and open burning of waste (section 5.4.1.2, Table 5.2), TERI, Energy profile: Pune rubber cluster (raw materials)

Last reviewed 2026-11-06. Defaults are from the 2006 guidelines. A measured fossil fraction for your own compound replaces both.