Since its development, the AshTech mixer-unloader system has been installed at hundreds of industrial and utility facilities to solve dust control problems.

  • Unit capacities range from under 5TPH to over 300TPH with multiple unit installations providing unloading capabilities of over 1000TPH.
  • Systems are in operation on fly ash from all types of coal-firing, wood, and refuse combustion; on pulverized, stoker, and fluid bed boilers; with cement, lime, coal dust, and other abrasive powders; on coal and biomass gasification plants.
  • Totally automated systems provide continuous, unattended conditioning, discharging to trucks, storage containers or take-away conveyors.
  • Customized designs have been developed to solve difficult retrofit situations.
Moisture Control Mixing Chamber System Design Material Feed

Material Feed Control
A variable-speed rotary feeder provides precise control of the material feed rate into the mixer.
Moisture Control
Multiple spray headers deliver a uniform curtain of water near the mixer inlet.
Mixing Chamber
The intersecting mixer paddle design insures a thorough blending of dust and moisture, producing a uniform distribution prior to discharge.
System Design
AshTech can provide complete integrated materials conditioning systems.


The AshTech mixer-unloader is a totally enclosed, twin-shaft paddle mixer designed to thoroughly condition and blend ash and other dusty, abrasive materials. Material feed rate into the mixer chamber is precisely controlled by a variable-speed rotary feeder. Water spray feed rate is adjusted by control valves. As material enters the mixer tub, inclined mixer paddles, mounted on the counter-rotating shafts, blend and mix the materials as it is conveyed forward. As the material is moistened by the wetting sprays, the interposing mixing paddles cause all dry surfaces to be exposed, resulting in a forced mixing and wetting of all material. The positive conveying action of the mixer paddles controls the material residence time as it is mixed and as it passes through the mixer and out the discharge chute. The result is a continuous flow of uniformly mixed product with no excess water and no dusting.

Mixer Unloader Systems

For Wetting and Mixing of Ash and
Other Dusty, Abrasive Materials.

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Bottom Ash Conveyors

Continuous Collection & Dewatering of
Bottom Ash & Coarse Abrasive Materials

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Dry Ash Conveyors

Dust-Tight, Air-Tight Conveying
of Dry Abrasive Material.

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Integrated Systems

Custom Designed, Integrated
Mechanical Ash Handling Systems.

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