Incinerator bottom ash consists of particles in the size range of 0-100mm and is commonly discharged wet from an incinerator. Processing plants recover Ferrous and Non-Ferrous (NF) metals, which can be divided into wet and dry operations. Modern wet systems can reliably cope with dry, moist or wet bottom ash.

Dry systems require dry input materials, but drying /curing of wet discharged bottom ash requires space, time and handling efforts. Fine particles (0-2mm) can’t be treated effectively by conventional eddy-current separators and when moist they cause sticking due to capillary forces in combination with high surface areas. Removal of fines from bottom ash prior to the treatment plant phase can be a solution to these problems.

Scrubbing brings fine particles into a slurry suspension, the subsequent drain screen removes the slurry from the coarse IBA (2-100mm), which can then directly be treated by an eddy-current separator plant without the presence of fines.

The benefits: No dust emissions, increased product qualities and separation efficiencies, reduced operations and maintenance efforts.

Sepro’s Fines Removal System (FRS) from IBA consists of a rotary scrubber and drain/dewatering screens. Fines from this system (0-2mm) can be processed in Sepro’s Fine Slag Treatment Plant (FSTP) for the recovery of precious metals.

Video: Sepro Scrubber Test on Incinerated Bottom Ash