Lime industry
Quicklime production necessitates high-temperature kilns to perform the calcination reaction, converting limestone into quicklime and CO₂. This analysis compares several lime production configurations based on energy demand and CO₂ emissions. These alternatives differ in terms of:
- Energy vector for heat supply – natural gas, biomethane, solid biomass, hydrogen, electricity
- Kiln technology – conventional air-fired kiln, oxy-fired kiln for concentrated flue gases, electrified kiln (plasma torches)
- Carbon capture technology – chemical absorption (MEA, for air-fired kilns) or cryogenic CO₂ compression and purification (CPU, for concentrated flue gases (electrified and oxy-fired kilns))
- Post-capture options – CO₂ is typically stored (CCS) but can also be reused for e-methane production (CCU)
Want to explore the emissions in more detail?
Click below to access the detailed assessment to examine how the different technologies and energy vectors contribute to overall CO₂ emissions.
Energy demand components (GJ/t lime):
- Q-Process – Thermal energy for limestone calcination
- EL-Process – Electrical demand for kiln operation
- EL-ASU – Electricity for oxygen production in oxy-fuel systems
- Q-CCS – Heat required by chemical absorption-based CO₂ capture
- EL-CCS – Power required by absorption-based CO₂ capture (Ch.Abs.) or cryogenic CO₂ capture (CO2CPU)
- EL-Electrolyzer – Electricity for green hydrogen production
Carbon capture (CC) impact:
Switch the toggle on to observe the impact of CC implementation.
CCS increases energy demand due to CO₂ separation and compression but reduces overall total emissions (emitted during calcination reaction, fossil fuel combustion, and upstream energy carriers production) per ton of lime.