ISKA® Percolation

The organics rich stream remaining from the sorting process is transferred to the ISKA® Percolation section of the Facility.

The Percolator and associated equipment, including the anaerobic digester, sand separator, sludge screen and water denitrifier form part of the patented ISKA Percolation unit process. The ISKA Percolation process design is based on many years of research and development effort and two operational facilities in Germany, with a further facility currently under construction. Global Renewables has secured exclusive licence arrangements for ISKA Percolation in Australasia and the United Kingdom.

ISKA Percolation achieves five key outcomes:

• Reduces the odour profile of the organic waste
• Reduces the mass of the organic waste
• Recovers energy from the organic waste
• Cleans the organic waste of contaminants (such as fine glass, sand silt, ceramics)
• Homogenises the waste stream (organic).

The organic rich stream from separation and sorting is fed into the Percolators. The Percolator uses wash water from the digester and operates in a semi-continuous fashion, loading fresh material and discharging washed and percolated solid residue during the operating schedule of the sorting facility.

The wash water is sprayed over the organic material in the Percolator. As the solution percolates through the stirred bulk waste, the volatile organic component of the MSW, colloidal material and sands are discharged to the sand washer. After passing through the sand washing and sludge removal circuits, the percolate solution is processed through the anaerobic digestion circuit. This produces biogas and excess water, which is then used in the composting operation.