Updated: July 2002

1. Outline

Okawara's fluidized-bed incinerator was developed based upon the experience and technical know-how acquired at circular incinerator (model ACE). The fluidized-bed incinerator has such wide application that not only the sludges but screen residues and other wastes can be incinerated. Furthermore, a low air ratio combustion difficult with this type of incinerator is possible with our fluidized-bed incinerator.
Due to high thermal capacitance of sand and excellent thermal conductance of fluidized-bed, the water is instantly evaporated from the sludges or screen residues.
Then, the product temperature is increased and the chemical reaction occurs, Incineration process is thus completed.
There is no local overheating area and a uniform temperature is kept in the incinerator furnace, and thus the fear for generation of ash clinker is reduced and energy can be saved, which are required for any types of incinerators.

2. Principle

In order to form a stabled fluidized-bed at a high temperature, the silica sand is filled in the incinerator furnace with optimum quantity.
When the fluidizing air heated with waste heat exchanger is blown from the bottom of the furnace, the fluidized-bed is actively formed in the sand layer. The product to be incinerated is supplied on the sand fluidized-bed and mixed with the sand while the sand particles are actively moving.
The water is instantly evaporated from the product and the product temperature is increased by the contact with hot air. The product is incinerated through these processes.
The ash produced by incineration is crushed into small pieces and discharged out of the system accompanies with the exhaust gas. Finally, the ash is collected with dust collecting system.

3. Structural Outline

4. Features

- Even the sludges or screen residues with high moisture content can be completely incinerated due to high thermal capacitance of sand and excellent thermal conductance of fluidized-bed.
- Small consumption of auxiliary fuel
- Extremely low ignition loss of ash
- Little fear for breakdown and durable construction
- Quick start-up
- Small site requirement

5. Applications

- Human waste sludge and sewage sludge
- Industrial wastewater sludge
- Waste less from industrial processes

6. Specifications

             Incineration                      Incineration
Model        Capacity kg/h         Model       Capacity kg/h
            (Water:80%W.B.)                   (Water:80%W.B.)
IFS-25           100              IFS-300          1,300
IFS-40           170              IFS-400          1,700
IFS-60           260              IFS-500          2,100
IFS-100          430              IFS-600          2,600
IFS-150          650              IFS-750          3,200
IFS-200          870              IFS-900          3,900

Note: The amount of sludge to be treated fluctuates, depending on the heating value of the sludge. This list indicates that the higher heating value, (Hh) of-solids is 3,800 kcal/kgds.