# Bagasse and black-liquor cogeneration

Sugar and paper mills burning their own residues for steam and power.

Source page: https://www.materialinsights.org/energy/e_bio_cogen/

Recovery and reuse · Heat to power and cogeneration · No. 129

- Recovery and reuse
- Heat grade: Process heat
 Recovery and reuse · Heat to power and cogeneration · Foundation · Energy

India's sugar mills burn their own crushed cane fibre to run about 9.8 GW of power plants.

Chart: Illustration: Bagasse and black-liquor cogeneration

##### Where it comes from

Chart: Map of where it comes from

Sugar and pulp mills burn their own residues, bagasse and black liquor, then pass the steam through turbines before using it in the process. Black liquor alone holds about 2 EJ of energy a year.

##### Three things to know

1. A 22 bar back-pressure sugar mill exports 0-10 kWh per tonne of cane, while a 67 bar condensing plant exports 90-120.
2. Recovery boilers also recover pulping chemicals as molten smelt, which can explode violently if it meets water.
3. Maharashtra (2,907 MW), Uttar Pradesh (1,986 MW) and Karnataka (1,869 MW) hold most of India's bagasse cogeneration.

##### The journey

1. 1 **Mill residue**Bagasse fibre or black pulping liquor
2. 2 **Boiler**Burns residue to raise high-pressure steam
3. 3 **Back-pressure turbine**Makes power while lowering steam pressure
4. 4 **Process steam**Feeds evaporators, dryers and juice heaters
5. 5 **Grid export**Surplus power sold to the utility
 Covered in [The laws of energy: conservation, entropy and efficiencyEnergy](https://www.materialinsights.org/learn/energy/laws-of-energy/)[Earth's energy flows: sun, wind, water, heat and lifeEnergy](https://www.materialinsights.org/learn/energy/earths-energy-flows/)

##### Go deeper pick a tab to open it in full

## Other sections

- [Overview](https://www.materialinsights.org/energy/e_bio_cogen/overview/index.md)
- [Correlation](https://www.materialinsights.org/energy/e_bio_cogen/correlation/index.md)
- [Science and thermodynamics](https://www.materialinsights.org/energy/e_bio_cogen/rc-sci/index.md)
- [Engineering and integration](https://www.materialinsights.org/energy/e_bio_cogen/rc-eng/index.md)
- [Economics and contracts](https://www.materialinsights.org/energy/e_bio_cogen/rc-econ/index.md)
- [Impact and additionality](https://www.materialinsights.org/energy/e_bio_cogen/rc-impact/index.md)
- [What to track](https://www.materialinsights.org/energy/e_bio_cogen/tracking/index.md)
- [Relationships](https://www.materialinsights.org/energy/e_bio_cogen/links/index.md)