Wastewater treatment authority Michael Bambridge of CST Wastewater Solutions says that the environmental shortcomings of open lagoon wastewater treatment systems are putting them at risk of obsolescence.
Popular with industry for most of the 20th Century for their simplicity of operation and economy, 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.
Food and beverage processors will be in the frontline of change along with primary processors including meat and dairy processors as well as operators of any industrial manufacturing or processing plant that draws water from its surroundings and returns water to the environment.
Mr Bambridge, whose company, CST Wastewater Solutions is one of Australia’s foremost exponents of anaerobic technologies that generate green energy from waste explains open lagoons not only expose the air, groundwater and runoff to pollution resulting in fish kills, algal blooms and bacterial contamination, but also waste energy in processing and oxygenation, when better designs could use the waste to produce green energy.
These cost-efficient and user-friendly technologies, proven by green energy pioneer Global Water Engineering in more than 75 industry plants worldwide 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%.
According to Mr Bambridge, leading companies such as those in the partnership that built Bluetongue (Coca Cola Amatil and SAB Miller) are acutely aware industry has to provide a lead toward more efficient technologies that are globally sustainable and 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
- 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
Mr Bambridge believes that companies should be pro-active in taking progressive action as responsible corporate members of the community, rather than have change thrust upon them abruptly and expensively.
He adds that good solutions do not have to be expensive and can be staged:
- 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
GWE’s RAPTOR (Rapid Transformation of Organic Residues) technology is a powerful liquid-state anaerobic digestion process that consists of enhanced pre-treatment followed by multi-step biological fermentation. RAPTOR can be used on food wastes, agro-industry wastes, industrial residues and energy crops.