Glossary
KPIs and measurements
Mass loading
Also known as dust loading, particulate loading, PM loading.
Mass loading is the particulate mass concentration in flue gas, typically expressed in g/Nm³ (boiler inlet) or mg/Nm³ (cleaned outlet). Mass loading at the inlet of an ESP or baghouse is the basis for sizing the equipment — higher inlet loading demands greater collecting area or more bag area to meet the same outlet target.
Typical inlet mass loadings
| Source | Approximate inlet loading |
|---|---|
| Coal-fired utility boiler | 10–40 g/Nm³ |
| Cement kiln | 15–80 g/Nm³ |
| Iron-ore sintering | 5–15 g/Nm³ |
| WtE boiler | 4–10 g/Nm³ |
| Biomass boiler | 3–8 g/Nm³ |
| Gas-fired combined cycle | < 0.05 g/Nm³ |
Outlet loadings after particulate control are typically 5–30 mg/Nm³ (ESP) or 1–10 mg/Nm³ (baghouse), often with sub-1 mg/Nm³ achievable on tight-emission applications using PTFE membrane bags.
Related terms
Related terms
- Particulate matterParticulate matter is regulated airborne particulate. PM10 = below 10 µm aerodynamic diameter; PM2.5 = below 2.5 µm; PM1 = below 1 µm. Smaller is more health-significant and harder to capture.
- Electrostatic precipitatorAn ESP removes particulate from flue gas by charging dust and collecting it on plate electrodes. Sonic horns are widely used to dislodge ash from plates and to keep hoppers from bridging.
- BaghouseA baghouse is the structural enclosure that holds the bags, cages, tubesheet, cleaning system and hoppers of a fabric-filter dust collector. Sized in compartments for online isolation.
- Collection efficiencyCollection efficiency is the fraction of inlet particulate captured by an ESP, baghouse or cyclone. Reported as a percentage; modern ESPs achieve 99.5%+, baghouses 99.9%+.