# How does a paper mill pulping bagasse or wheat straw report biogenic CO2?

Canonical: https://senseible.earth/answers/agro-residue-paper-mill-biogenic-co2

CO2 from burning bagasse, straw, pith or black liquor in the boiler is biogenic: report it separately, outside the scopes. Methane and nitrous oxide from that burning, and all CO2 from coal or oil, stay in Scope 1.

## Three buckets

- Scope 1 fossil: coal, lignite, petcoke or oil burnt in boilers and lime kilns.
- Scope 1 non CO2: methane and nitrous oxide from biomass and black liquor combustion, from IPCC defaults per TJ.
- Biogenic CO2: reported separately, not added to the Scope 1 total.

## Lime kiln

CO2 from calcining lime mud in a kraft style recovery cycle is biogenic too when the carbonate comes from the pulping chemistry, but fuel burnt in the kiln is counted by fuel type.

## Evidence

Keep purchase records for bagasse and straw, and black liquor solids fired. Buyers and verifiers ask how biomass quantities were measured.

## What Senseible does here

Senseible reads electricity bills (CEA grid factor 0.710 kg CO2 per kWh, CO2 Baseline Database version 21.0) and diesel, LPG and gas invoices (IPCC 2006 defaults) into a dated, fingerprinted Scope 1 and 2 record for each site. Intensity per unit uses the activity count you enter, and estimates are labelled as estimates.

- [ISO 14064 biogenic CO2 reporting](https://senseible.earth/answers/iso-14064-1-biogenic-co2-reporting)
- [Paper mill per tonne](https://senseible.earth/answers/paper-mill-carbon-footprint-per-tonne)
- [Sugar mill bagasse cogeneration](https://senseible.earth/answers/sugar-mill-bagasse-cogeneration-emissions)

Sources: [GHG Protocol Corporate Standard](https://ghgprotocol.org/corporate-standard), [IPCC 2006 Guidelines, Volume 2 Energy](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html)

Last reviewed 2026-10-21.