It is estimated that electricity consumed to treat sewage in industrialised countries represents 1.0 to1.5% of total electricity consumed in these countries. In Australia, this represents between 2.2 billion and 3.3 billion kilowatt hours of electricity. This represents CO2 emissions of 2 to 3 million tonnes per annum
BiOWiSH technology can offer the potential to reduce the energy required for aeration in modern sewage treatment plants by up to 50%. As per the summary data for Sydney, Melbourne, SEQ and SW Western Australia (largely Perth), the volume of bio-solids produced in Australia is 163,500 tonnes (dry weight). (Source: Advanced Water Management Centre, University of QLD, Australia (April 2009)
Over the past eight months, Bathurst Regional Council have been conducting a world first trial of a new technology that promises to offer significant improvements in energy consumption and the production of bio-solids from sewage treatment.
The new technology promises to reduce greenhouse emissions from waste water treatment operations globally. It will also help to decrease the volume of bio-solids produced. Bio-solids are recognised as a hazardous waste with a high cost of disposal.
The Bathurst Regional Council have offered their sewage treatment plant over several decades to participate in trials that have assisted the waste water industry to develop new plant designs and technologies.
According to David Swan, Bathurst Regional Council Manager, Water and Waste Authority, the work done at the Bathurst plant over the years has given rise to a design of sewage treatment plant known as the ‘Bathurst Box’, which is now widely adopted in Australia and overseas. The adoption of this new technology, which could reduce energy cost and therefore greenhouse gas emissions as well as bio-solids, would be a good innovation for the waste water industry, regional councils and the environment.
BiOWiSH Technologies have been participating in trials with Bathurst Regional Council with a revolutionary enzyme based approach to waste water treatment.
Using high speed enzymes that were discovered in natural mangrove environments, the technology promises to reduce the reliance on bacteria and other micro-organisms to breakdown sewage and reduce nutrient levels prior to discharge into the environment. This will result in lower energy requirement for aeration of the waste water, and a reduction in the final bio-solids produced through the process of sewage treatment. There is also a benefit of less odour emissions, thereby improving conditions for local residents.
According to Rod Vautier, Chief Executive Officer, BiOWiSH Technologies, the technology will assist the environment, waste water treatment industry and governments in many ways. Any contribution to reduce energy consumption and therefore greenhouse gas emissions is highly valuable and the adoption of this technology offers the potential for reductions in electricity for aeration of up to 50%.
The BiOWiSH enzymes rapidly breakdown the waste matter and therefore less bio-solid material is theoretically produced in the plant. This is also good for the environment. The technology can be applied to any existing biological treatment plant at low cost, and in the developing world, it could meet growing capacity needs without increasing capital expenditure. This means public health outcomes can be improved as untreated sewage is a major cause of disease in the developing world.
When the first collection and treatment works were constructed at Bathurst, in the late 19th century, the levels of infectious disease and infant mortality dropped by 90%. Early indications were encouraging with the strength of the sewage being reduced by up to 83% and the solids by up to 90% prior to entering the aeration chamber for traditional biological treatment. This should translate to substantial energy reductions and potential plant capacity increases without the requirement for significant capital equipment.
Further trial work is to be considered for later this year to verify the actual reductions in aeration energy and final bio-solids production.