Abattoir wastewater is a mixture of

  • water generated by cleaning of holding areas,
  • processing water from both the evisceration and slaughtering lines, and
  • water used for cleaning the slaughtering equipment and facilities.


The ever-changing mix of the above wastewater sources causes a large variation of the main pollutant, namely organic matter. The contributors of organic load to these effluents are paunch, faeces, fat, oil, grease, undigested food, blood, suspended material, urine, condemned meat, soluble proteins, manure, grit and colloidal particles.


Abattoir wastewater is characterised as high strength (high COD), high volume wastewater with relatively low suspended solids. For example a medium size poultry abattoir will process 20,000 chickens per day using roughly 17 litres of water per bird. After screening, the daily discharge is 340,000 litres of pink fatty water.


The most widely used route for disposal of abattoir waste is municipal sewers. Discharge costs due to the high organic strength of untreated abattoir waste is relatively high. Abattoirs traditionally have difficulty in meeting municipal by-laws for discharge of fats, oils, greases and suspended solids.





  • Discharge to the environment that meets General Discharge Standard
    • High process efficiency - >90% destruction of organic loading.
    • Nitrates and Nitrites reduced through the AD process and ion exchange
    • Pathogens are largely destroyed by anaerobic digestion.


  • Reduced CAPEX Cost
    • Feedstock concentration to improve organic loading of wastewater sent to AD plant thereby reducing plant size.
    • Less than 10 day HRT, depending on individual circumstances.
    • Smaller footprint, at least 70% smaller than a traditional plug-flow systems, resulting in greatly reduced excavation and containment costs.


  • Reduced OPEX Cost
    • Collection and use of biogas can result in a negative operating cost with system payback of approximately 5 years.
    • High system efficiency results in high energy yield
    • More organics treated (> 90% destruction of organics) combined with high methane content biogas (typical methane content 75-85%) results in a superior energy yield.
    • Plant requires low parasitic load thereby allowing for greater energy export
    • Treated water can be recycled for general plant use thereby saving on water costs
    • Discharge to municipal system does not incur surcharges for not meeting specification.


  • Little or no organic sludge
    • Mineral sludge has high value and is an effective nutrient recovery system


  • Unsurpassed process stability with the addition of Biocomplex bio-activator
    • Enhanced biological reaction that improves biological wastewater processes
    • Prevents the generation of anaerobic odours
      • Stops the production of hydrogen sulphide through natural ion exchange capacity
      • Increases the rate of nitrogen cycling by promoting the conversion of ammonia to ammonium


    • Greatly increases bacterial metabolic rate by supplying essential nutrients and trace elements
    • Improves the ability to handle shock loads as microbes have less die-off in their restive state
    • Improves bacterial breakdown of organic material as microbe activity is enhanced




Selectra’s sustainable architecture for treating abattoir waste streams is centred on producing energy, discharge standard effluent, and water for re-use. Treatment costs are recouped through the reduction in municipal surcharges associated by not discharging high COD wastewater into the municipal system, reduction in energy costs, sales of tallow, and water reuse. Energy costs are reduced by production of high quality biogas, a natural by-product of the H2E anaerobic wastewater treatment system. The biogas fuels a CHP generator thereby supplying the facility with electricity and hot water.


Selectra’s sustainable abattoir architecture successfully addresses the main obstacles that has limited technology uptake in the past, by effectively concentrating the organic solids in a smaller waste stream to reduce plant size and subsequent treatment of the wastewater to allow for reuse in the plant.

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