Solids handling equipment specialist, Ajax Equipment, has supplied one of the UK’s leading providers of resource management with three ash handling systems and a large ash conditioner for the processing of Air Pollution Control Residues (APCr).
Each system consists of a modified silo and quadruple screw feeder, as well as the associated collecting conveyors and elevators. The handling systems provide a reliable feed of material to the ash conditioner.
Following flow property testing of the ash, Ajax Equipment found that the customer’s site did not have the headroom required for the material’s ideal silo design.
As a result, Ajax devised, designed and carried out a range of modifications to the existing silos as well as introducing multi-screw feeders below to ensure flow reliability and achieve the performance desired.
Each of the three quadruple screw feeders provides active extraction of APCr from the silo above as well as delivering a reliable feed to the system’s collecting screws. Ash is then transferred to the twin screw ash conditioner via two screw elevators.
Based on Ajax Equipment’s continuous mixer technology, the conditioner’s design ensures the thorough mixing of ash with the acidic liquid by using spray bars to deliver a controlled supply of liquor directly to where the mixing action is greatest, converting it from hazardous to a material appropriate for storage.
In addition to its nature, APCr also requires considered handling as it is likely to set in the conditioner if allowed, affecting performance.
To prevent the ash and liquor mixture setting and minimise operator exposure, a clean in place system was devised for the conditioner. Swivelling spray bars with profiled spray nozzles provide good cleaning coverage, while the conditioner’s counterbalanced covers allow easy inspection and maintenance.
“From Ajax’s involvement in effective continuous conditioning of ash to our experience and expertise in feeding and transport of powder, each was called on to ensure maximum production capability and reliability,” commented Eddie McGee, managing director, Ajax Equipment.
