A unique sludge melting furnace is developed for the volume reduction and energy creation, Mitsubishi vertical type swirling slagging furnace, based on our technologies in sludge incinerator, boilers, oxygen enriched low NOx combustion and two-stage vertical swirling slag-tap combustor for coal gasification.

2. Characteristics

1) No more melting agent or aux. fuel

Oxygen enriched air by compact oxygen generator can incinerate and melt sludge at high temperature, which requires no melting agent or aux-fuel to get smaller slag volume and lower operation cost.

2) Stable operation

Vertical swirling furnace exhausts gas to top and extract slag at bottom center, achieving even distribution of temperature and slag layer alongside wall, and stable operation.

3) Highest controllability against load variation

Oxygen enriched combustion has realized easy control of furnace temperature by adjusting oxygen volume only, achieving stable slag out-flow.

4) Long-life construction

To fight with heavy condition of above 1,500 deg. C, the furnace wall is designed as refractory with water jacket which materialized even slag flow, forming solid and liquid layers for wall protection to longer life.

5) Low NOx emission level

Oxygen-enriched reduction combustion at melting furnace, and self denitrification of exhaust gas at secondary combustor, this has achieved low NOx emission, and no requirement of de-NOx equipment and its operation cost.

6) Small gas volume

Oxygen enriched combustion can reduce N₂ volume of combustion air, giving smaller exhaust gas volume, and compact gas treatment equipment.

Swirling slagging combustor oxgen enriched high rate burning (1400-1600 deg.C)

Stable slag flow from center-tap

Sludge slagging combustor

Slowly chilled slag

Pebbled slag

Fibered slag