2020-11-10 Services & Organisation Committee Agenda

SERVICES & ORGANISATION COMMITTEE MEETING AGENDA                             10 NOVEMBER 2020


    Thermally destroy residual waste in a moving grate incinerator and use heat from the
      incineration process to generate electricity for sale to offset some of the operational costs.
      (Capital costs for this facility could exceed $400 million).
    Establish a separate governance model to manage the construction and operation of the
      regional treatment facilities through Unitywater or some other governance structure
      acceptable to the participating MOU members.
4.    Local Government Response to The Report Recommendations
4.1   Anaerobic Digestion (AD)
A regional anaerobic digester would require local governments to:
    Implement or expand existing garden waste collection services to a weekly FOGO
      collection
    Transport the waste to a regional AD facility.
    Reduce the red lidded general waste bin to a fortnightly collection, typical of what occurs
      when this service operates in other area of Australia.
Benefits:
A regional anaerobic digestor provides a cost-effective solution for both Unitywater and Councils,
without each entity building separate treatment facilities unique to their own operations. Other
benefits:
    A weekly FOGO collection service is an economic solution as the costs for the increased
      (weeky) servicing frequency of the FOGO bin is offset by the reduced collection costs of
      the red lidded general waste bin, (serviced fortnightly).
    AD reduces the generation and escape of methane from landfill.
    AD reduces the volume of landfill air space consumed and extend the landfill life.
    The sealed treatment process facilitates capturing methane and generate electricity for a
      revenue stream to offset costs.
    Improves the marketability of sewage sludge after treatment thought AD.
Concerns:
Organic Waste (FOGO) bin contents for treatment in a wet AD process when mixed with bio
solids to generate electricity cannot take branches larger than about 25mm thick or palm fronds.
The available options considered:
    Pre-sort the collected FOGO bin before inclusion in the AD to remove larger branches and
      palm fronds. This would require two treatment processes and potentially increase costs,
      which is undesirable compared to the current low-cost system of mulching all garden
      waste, branches and fronds for reuse.
    Larger branches from 25mm up and palm fronds, which are currently mulched and recycled
      could go into the red lidded bin to landfill but this would be undesirable.
    Provide 4 waste bins – waste, recycling, garden waste, and food only waste. The GW bin
      could be locally mulched and 4th food only bin sent to a central AD for inclusion with
      sewage sludge.
The consensus of local government representatives was that a 4th bin for food only would
significantly increase service costs and there would be limited acceptance by residents for
various reasons e.g. bin storage space at domestic premises.
4.2   Moving Grate Incinerator for Residual Combustible Waste
A moving grate incinerator is a technology that has been implemented internationally for many
years. It can accept a wide range of material, with mechanical pre-sorting before incineration to
remove some non-combustibles. The technology produces residual ash from the combustion
process and this may require landfilling. Heat from the combustion process is used to power a
generator to produce electricity for sale.

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