Lignin is made by plants from carbon dioxide taken from the air, so lignin products are often linked to carbon sequestration. Some of those claims go further than the evidence. This page explains what lignin-based products do with carbon, and what Green Agrochem can and cannot claim today.
What carbon sequestration means
Carbon sequestration is the long-term storage of carbon that would otherwise be in the atmosphere as CO₂. To count, the carbon has to stay stored for a long time, and the amount has to be measured against a baseline.
Where the carbon in lignin goes
| Use | What happens to the carbon | Long-term storage? |
|---|---|---|
| Concrete and gypsum admixtures | A small dose is bound in the hardened material for its service life | Possibly, but the amount per tonne of concrete is small and has not been measured |
| Soil, fertiliser and lignohumates | Applied to soil, where it is expected to degrade over time; part may contribute to soil organic matter | Not established for our products; it depends on soil, climate and time |
| Dust control | Applied to roads and gradually broken down or washed off | No |
| Feed binders | Eaten and digested or excreted | No |
| Burned for energy at the pulp mill (the alternative) | Released as CO₂ immediately | No |
What we can claim
- Our lignosulfonates are made from lignin, a bio-based material, recovered from a pulp-mill side stream.
- Using that stream as a product, rather than burning it, keeps its carbon in a product for the product’s service life.
What we do not claim
- We do not claim our products sequester a measured amount of carbon.
- We do not take part in carbon-credit or carbon-removal projects.
- We do not publish a carbon footprint, because no life-cycle assessment (LCA) has been completed.
If your project needs a carbon figure for a lignin product, it has to come from an LCA or a measured soil-carbon study. For the documents we can provide now, see ESG documents.
Frequently Asked Questions
Does lignin sequester carbon?
Lignin contains carbon that plants took from the air. Whether a lignin product stores it long-term depends on the use: bound in concrete it may stay for the material’s life, but in soil, roads or feed it is expected to degrade.
Do lignosulfonates reduce carbon emissions?
They use a pulp-mill side stream that would otherwise be burned, but no life-cycle assessment has been completed, so we cannot state an emissions reduction for our products.
Does Green Agrochem take part in carbon-removal projects?
No. We do not take part in carbon-credit or carbon-removal projects and do not claim a measured sequestration amount.