Attachment 3B - Process Design Strategy - OREZ · 132005.638.06

PR25001 Noosa Composting Facility
Process Design Strategy




   1. Option 1 – Second screening step downstream of the drum screen, splitting the
      oversize into a graded mulch product and a coarse fraction disposed of or returned
      to the process as bulking agent when space is available within a tunnel and
      depended on seasonal fluctuations. This adds a screening step, a further conveyor
      and an additional storage bay / using one of the existing ones.
   2. Option 2 – Secondary screening of the oversize on a campaign basis using mobile
      plant, avoiding fixed capital but adding operating cost and plant hire, and requiring
      additional hardstand for the campaign.
   3. Option 3 – Secondary screening on a campaign basis using NSC-owned mobile
      plant, avoiding both fixed capital and plant hire, subject to NSC holding suitable
      screening plant with available capacity, and still requiring additional hardstand for
      the campaign.

Recovering a graded mulch product from the oversize fraction reduces the tonnage leaving
site as low to no value material. Progressing any option requires a market view of what
graded mulch achieves per tonne in the Noosa catchment against the current oversize
disposition. The achievable product specification and price for each grade, should be
developed by NRC to enable assessment.




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