A major waste-to-energy project in Queensland is being used by CST Wastewater Solutions at FoodTech Qld 2019 to show food and beverage producers how environmental responsibility can be a profit not a cost.
The technology involved in the green energy initiative by meat processor NH Foods Australia at their Oakey Beef Exports facility is already paying handsome dividends in terms of cleaner wastewater effluent, as well as a reduced fossil fuel environmental footprint and lower energy costs.
In addition to food and beverage processors, the technology can be applied to agribusiness operations including all forms of meat, livestock, poultry, fish and agribusiness, including fruit, sugar, vegetable, grains and other crops.
The Global Water & Energy (GWE) COHRAL(Covered High-Rate Anerobic Lagoon) plant involved was installed at Oakey by Australian environmental engineering and green energy authority CST Wastewater Solutions, which recently inspected the plant as it reaches its landmark fifth year of service in southern Queensland.
Replacement of fossil fuel
It found the clean, compact and robust plant is in outstanding condition, having required only routine maintenance over that time as it continuously produces 3000-4000 m3 of biogas a day, depending on plant throughput. The generated biogas is directly used in the plant’s existing boiler replacing natural gas. This leads to replacement of fossil fuels and sharpened cost-efficiencies at a time they are most needed during the current Australia-wide drought.
The anerobic digestion plant extracts green energy biogas from Oakey Beef Export’s wastewater streams to replace millions of dollars’ worth of natural gas over its operating life, in Queensland’s Darling Downs region.
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Instead of effluent being stored in energy-costly and extensive aerated lagoons used by many food and beverage business – with associated environmental, OH&S hazard, water and odour issues – waste at Oakey is converted to biogas by a clean, green and reliable anaerobic digestion process applicable to any food, beverage or primary processing plant with an organic waste stream.
The compact GWE COHRAL™ plant involved occupies just half the footprint of comparable covered anaerobic lagoons and a much smaller space required by typical energy-hungry and odorous open aeration lagoons in service globally, says CST Wastewater Solutions Managing Director Michael Bambridge.
The necessary pretreatment prior to the GWE COHRAL system lead also to better recoveries of valuable protein and fats, which would normally end up in the wastewater.
By transforming a wastewater effluent treatment and disposal problem into an ongoing productive asset, the plant has achieved a rare business and environmental ideal of cleaner, greener performance with stable, predictable and profitable supplies of biogas.
The Oakey plant is designed to produce biogas (primarily methane) which is stored for use in a 6000m3 capacity flexible PVC-coated polyester storage balloon from which biogas is drawn to fuel the boiler.
The new plant simultaneously delivers high quality wastewater by extracting organic content, which it converts into methane to replace fossil fuels. The GWE technology involved removes 80-90 per cent of organic waste content, to give cleaner effluent while also reducing odours.
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