Despite being one of the driest continents in the world, Australians are among the biggest users of water globally. However local manufacturers are reversing this trend. Katherine Crichton looks at how.
AUSTRALIA has one of the lowest rates of rainfall of all the continents, and while two thirds of all the people on earth use less than 60L of water a day, the average Australian uses more than twice that amount during a single shower.
Unfortunately this casual attitude to water consumption also extends to Australia’s commercial sector, but with rapidly increasing water costs draining profits, companies are looking at innovative ways of reducing the consumption and cost of mains water in their operations.
A case in point is Melbourne-based water pump and pressure system manufacturer, Davey Water Products. In 2006, the company installed a rainwater capture system as a demonstration project at its pumps production plant in Scoresby, and in 2008, is literally reaping the rewards, both environmentally and financially.
Max Ekins, Davey Water Product’s market manager – water conservation and treatment, told Manufacturers’ Monthly while the company had long been enjoying market success with its water conservation products, they came to the realisation they needed to improve the company’s own water management practices.
“We believe in ‘walking the talk’ and after identifying a number of high water consumption processes in our new manufacturing plant, we initiated one of the first commercial rainwater harvesting projects on our own roof, not only to reduce our own consumption but to demonstrate the potential for this approach in an industrial setting,” he explained.
“We had all the necessary equipment, so it was basically a matter of retrofitting our guttering to a syphonic drainage system and then storing the water run-off from the plant’s 2,500m2 in three 45,000L above ground rainwater tanks for delivery to the paint line using the company’s new HM series multi-stage electric pump set,” he said.
After simple filtration, the rain water is also used in the factory and adjoining office area for non-mains water needs such as toilet flushing
Rainbank automatic controllers at each use point automatically switch the supply back to mains water should there be insufficient rain water in storage.
“As a result, we have reduced potable water use by 50% or one million litres per year.”
Ekins believes there are many drivers for companies to invest in this kind of technology, especially for inner city companies with large commercial usage of water and the company has also been working with the Queensland Water Authority to write regulations for rainwater harvesting and in January this year, the practice was mandated in all new commercial properties.
“Without a doubt water prices are going to rise in the future, so rainwater harvesting is a way of future-proofing your business, particularly if you are a high water user.”
Tapping into water savings
Queenland’s iconic Buderim Ginger factory at Yandina on the Sunshine Coast produces quality confectionary ginger products with a capacity to process in excess of 6,000t of raw ginger each year.
The company’s core objectives in establishing water and energy saving technology at the facility was to lessen the impact that ginger processing and production had on the local region’s natural resources.
Harvested ginger is held in preservation vats until is it ready to be processed. The ginger is preserved in a brine solution of town water and sodium metabisulphite. Sulphite is an oxygen scavenger that removes all bacteria, bleaches the ginger and softens the rhizome. To ensure the end product is of the highest quality, all sulphite is then removed from the ginger rhizomes.
In the past, this cleansing was done using copious quantities of hot water, all of which was dumped into the sewer drain.
Buderim Ginger Chief Executive Gerard O’Brien said a major consideration for the company was to ensure that the implementation of any new methods of water and energy usage did not slow the process of ginger production down and therefore have a negative financial impact on the business.
“Over a six year period we trialled several new technologies and after further investigation, decided that Ozone technology would be a suitable oxidant to remove sulphite and impurities in the re-used water,” O’Brien explained.
With the support of the Queensland Government’s $55m Business Water Efficiency Program (BWEP), which provided almost $90,000 in funding to assist Buderim Ginger install the technology, a sulphite stripping system was designed to reuse flushing water from ginger and return it to a central storage system.
The storage system holds approximately 300,000L and is continuously ozonated to remove the sulphite. An additional chlorine dioxide dosing unit controls bacteria levels.
Water is circulated through the system from the storage tanks to syruping and returned via six pumps. Each syruping chain has a supply and return line with recycled water available to all 63 processing tanks.
“As well as significant water savings of over 25.6 million litres a year, we are also experiencing massively reduced operating costs as this technology allows us to recover the heat from the water used in the flushing process, eliminating excessive use of energy,” he said.
“Because this is a highly efficient method of removing sulphate from processing water, the heat exchanger takes already-used hot water from the factory and uses it to heat the ozonated cool water coming into the factory, saving 22 million litres of water per annum and a reduction in energy usage of approximately 20%,” he said.
The Queensland-based ginger producer is not only enjoying a reduction of more than 50% in town water usage but is revelling in the clean corporate image this project has provided.
“Our green efforts are good for business, resulting in significant bottom line results, and we have set a new global benchmark for water efficiency in the ginger industry,” he said.