Michael Bambridge of CST Wastewater Solutions and a leading wastewater treatment authority observes that underperforming open industrial wastewater treatment lagoons are on the way out as industry counts the cost of their pollution, odours, leakage, energy wastage and relative inefficiency.
According to Mr Bambridge, open lagoon wastewater treatment systems were popular with industry for most of the 20th Century due to their cost-effectiveness and operational simplicity. However, these systems are now recognised for their environmental downsides including their poor ability to control algae and suspended solids in warm weather, and poor efficiency in removing pollution load.
The advent of increasingly global carbon taxes, community activism, and greater legislative awareness of environmental shortcomings are driving change that will see industry searching for better ways to reduce problems created by effluent from uncovered lagoons.
Besides polluting the air and groundwater, open lagoon systems also waste energy in processing and oxygenation, when better designs could use the waste to produce green energy. CST Wastewater Solutions is one of Australia’s foremost exponents of anaerobic technologies that generate green energy from waste.
Proven by green energy pioneer Global Water Engineering in more than 75 industry plants worldwide, these cost-efficient and user-friendly technologies were most recently used in Australia to reduce the dependence of the $120 million Bluetongue brewery on fossil fuels and ultimately cut its overall energy needs by 15%.
Mr Bambridge believes leading companies such as those in the partnership that built Bluetongue (Coca Cola Amatil and SAB Miller) are acutely aware of industry’s responsibility towards implementing more efficient technologies that are globally sustainable and will position companies as a responsible partner in the sharing of community resources including clean water and clean environments.
Challenges facing industry in the treatment of its wastewater:
- Old and worn wastewater treatment and collection facilities employing obsolete technologies need to be improved or replaced to treat more complex pollutants
- Population growth taxing reserves of shared community resources such as clean water, clean air and land for urban development and sustainable agricultural uses is also leading to conflict between land uses
- Environmental awareness becoming a mainstream voting issue that spreads up from the level of individual communities confronting polluters through to local, State and Federal governments regulating for change
- A satisfactory first step is to cover lagoons and incorporate anaerobic processes with properly designed feed and recycle systems, which will not only solve many odour emission problems, but also generate green energy in the form of captured methane that can be burned to power industrial processes or generate electricity while also reducing carbon emissions
- A second progressive step can involve the use of tanks to contain anaerobic and other processes, minimising land use, reducing plant footprints and providing high security against leaks and groundwater contamination while simultaneously controlling anaerobic processes efficiently to optimise water purification and green energy production
- A third optimum stage can be the eventual incorporation of advanced anaerobic technologies into sealed tank environments, such as GWE’s RAPTOR treatment system for organic residues, which can convert almost any organic residue or energy crop into biogas, valuable electricity or heat
Its RAPTOR technology (Rapid Transformation of Organic Residues) is a powerful liquid-state anaerobic digestion process that consists of enhanced pre-treatment followed by multi-step biological fermentation. The removal efficiency of GWE’s anaerobic wastewater treatment installations has been demonstrated globally to be as high as 90-95%, bringing the organic load down to regulatory discharge standards for some types of wastewater. RAPTOR can be used on food wastes, agro-industry wastes, industrial residues and energy crops.
Anaerobic digestion facilities have been recognised by the United Nations Development Programme as one of the most useful decentralised sources of energy supply, as they are less capital-intensive than large power plants. They can also benefit local communities by providing local energy supplies and eliminate the need for large and often smelly and environmentally challenging settling lagoons.