Alleima provides stainless steel tubes for lime kiln lances. Our lance tubes provide long service life and reduced maintenance costs, particularly under the severe high-temperature corrosion conditions encountered in lime kilns. Our stainless steel lance tubes are therefore a cost-effective alternative to lance tubes in conventional grades of, for example, ASTM 310H and 316H types.
| Alleima grade (UNS) |
Description |
|---|---|
| Alleima® 253 MA* (UNS S30815) |
Austenitic stainless steel alloyed with nitrogen and REM (rare earth metals). A multi-purpose grade suitable for temperatures from 600 to 1000ºC (1112 to 1832ºF). |
| Alleima® 353 MA* (UNS S35315) |
Austenitic stainless steel alloyed with nitrogen and REM (rare earth metals). Suitable for oxidizing, carburizing and nitriding conditions. Suitable for temperatures from 800 to 1150ºC (1472 to 2102ºF). |
| Alleima® 4C54** (UNS S44600) |
Ferritic stainless steel with a high chromium content (26.5%) suitable for sulphudizing conditions. Suitable for temperatures from 600 to 1000ºC (1112 to 1832ºF). |
class="table-notes">* 253 MA® and 353 MA® are trademarks owned by Outokumpu OY.
** Alleima® 4C54 performs well also under sulphidizing conditions.
Different types of kilns
Often referred to as "quicklime", lime is the product obtained by burning limestone and other calcium-rich substances. Limestone is comprised of calcium carbonate (CaCO3), which breaks down during the burning process to produce calcium oxide (CaO) or lime, and carbon dioxide (CO2), which is released, leaving the lime in a lumpy or powdery form which is usually white. Both weight and volume losses occur during the process.
| Main types of kiln (%) | Typical energy efficiency |
|---|---|
| Rotary (18%) | 45% (pre-heated 60%) |
| Shaft (13%) | 75% |
| Parallel Flow Regenerative (51%) | 85% |