Water and Wastewater

A leading New Zealand food processing company committed to ongoing excellence in sustainability has become an early adopter of a sludge dewatering technology engineered to cost-efficiently reduce the environmental footprint of food, beverage, and wastewater treatment throughout Australasia.  The international fruit processing facility in Hawkes Bay (which cannot be named for contractual confidentiality reasons) processes tens of thousands of tons of fruit for both local and export markets, using a compact and cost-efficient KDS multidisc roller system from CST Wastewater Solutions as part of their process.  The low-energy KDS technology from Australian company CST Wastewater Solutions dewaters wet, sloppy screened waste from the processing of fruit such as such as apples and pears, reducing waste volumes by up to 90 per cent.   It transforms the waste to a much drier product that is less messy, easier and hygienic to handle, and cleaner to transport for recycling to stockfeed for the rich agricultural region of Hawkes Bay.  In addition to saving fossil fuel and other transport and disposal expenses – which can amount to hundreds of dollars a ton – the drier waste helps protects water tables and conforms with the strong environmental and pure food credentials of the processor.  The fruit processor – located in an area famous for its fruit production – has previously won an export awards in which the judges of which said they liked the level of engagement across the wider team in developing the company vision, and the continuous improvement and commitment to innovation was genuinely impressive. The factory was well laid out and the effort that was put into health and safety stood out.  CST Wastewater Solutions Managing Director Mike Bambridge said the durable stainless steel KDS technology was another step forward in the company’s cleaner/greener process enhancements and new state-of-the art facilities, which are designed to benefit the entire region and community of which the company is part.  “In service, the KDS technology does everything it is meant to. It is true to its claims,” said Mr Bambridge, adding that the KDS typically handles 6m3 (approx. 100-150kg) per hour of sloppy waste containing leaves, twigs and unsuitable fruit. The output is transformed into waste for disposal or stock food, that is much cleaner, neater and healthier to handle.  “Reducing waste volume by up to 90% radically reduces transport costs and helps prevent any potential spillages onto public roads during transport. Both issues are very important, with rising specialised waste disposal transport costs and with local communities and councils very mindful of how companies treat waste. The company using the KDS technology is setting an example of good practice in both areas.   “It is a win-win environmentally and operationally because there are both operational and OH&S benefits, with the site being cleaner and easier to maintain and the financial gain of not paying for transport and disposal of unnecessary water. Heavy cakes of byproduct from growers and food processors generally can cost upwards of $150 a ton to dispose of, including the specialised transport from the places where trade wastes are generated, to centres where compacting, drying, recycling and disposal can take place in controlled environments,” says Mr Bambridge, who worked with CST Wastewater Solutions NZ Manager Mr Pieter Groenewegen during the installation.   The fruit processor uses the KDS technology to handle a highly variable quality and volume of up to 6m3/h. “This first NZ adopter of the KDS technology had previously tried alternative technologies, but none handled the variable volume involved or dewatered the fruit waste enough to prevent excess water and product from creating an unhygienic site and causing leakage,” said Mr Bambridge.  The application uses a KDS model SS611 with a longer press zone, to achieve optimum dewatering of the sloppy and wet mix of peelings, leaves and pulpy fruit material.  “The dewatering concept being employed in this instance is to spread the waste over the table width and dewater a mat of material, to maximise the surface area and minimise water retention.”  “This is an outstanding application of this globally proven technology, which is eminently suited to the food and beverage processing industry. It also very cost-efficiently advances the environmental credentials of a significant member of the Australasian fruit industry, while being a major contributor to the local and export agricultural market,” said Mr Bambridge.    Other KDS applications include thickening and dewatering of Dissolved Air Flotation (DAF) sludge – a very common wastewater application – the KDS achieves solids capture of 95-99% sludge at a dryness of 15-20%. Waste activated sludges are typically 15-18% dryness. This high quality, Japanese-manufactured technology:  Uses minimal energy, consuming as little as 0.06kW hr of electricity   Operates at low (63dBa) non-intrusive noise and vibration levels  Does not need water to keep clean, eliminating aerosol OH&S problems Requires minimal daily maintenance, saving cost and enhancing OH&S performance  Occupies typically half the space or less of conventional dewatering plants  Is engineered to overcome the limitations of technologies such as screw presses, belt presses and centrifuges typically employed by small-to-medium applications to treat the sludge produced by their operations.   The mid-size KDS unit can handle about 100kg DS (dry solids) an hour at 98 per cent solids capture, says Mr Bambridge. The largest unit can handle 310kg DS an hour.   This lighter, dryer waste produced – in addition to being easier and cheaper to transport – reduces the labour for cleaning and cleans up transport operations for any fruit, juice, vegetable, and food production facilities, including kitchens and catering. In fact, this applies to any livestock, horticulture, agribusiness producing waste during production and processing.   The technology is also suitable for municipal and remote industrial worksite waste handling. where its cost-effectiveness and low-maintenance operation is a major advantage where engineering support may be far distant. 

Tooleybuc’s cost-effective ultrafiltration system, top and floods in the Northern Rivers Districts, below Dorothea Mackellar summed up Australia’s climate beautifully with the opening lines of My Country: “I love a sunburnt country, A land of sweeping plains, Of ragged mountain ranges, Of droughts and flooding rains.” And one company that know these climactic extremes to be true is CST Wastewater Solutions, whose advanced technologies are helping to drought-proof communities and at the same time protect them against the impacts of flooding. In the first case study, Wakool Shire Council was concerned about the declining quality and quantity water resources, especially during times of drought or dry weather. They decided to install a CST ultrafiltration system in their plant at Tooleybuc, which not only improved the quality of water, but also required less maintenance than the old plant. In the second case study, Richmond Valley Council upgraded to a finer screening at their Sewage Treatment Plant, which reduces blockages and allows for a more efficient treatment with less ongoing maintenance. It was a fortuitous upgrade for Richmond Valley, which received an intense storm just days after the project was completed. The following text is a detailed account of each case study. Drought Challenge: Tooleybuc NSW Municipal councils all over Australasia are seeking optimum ways to address challenges posed by water resources declining both in quantity and quality under pressure from local populations and the needs of industrial and agricultural users. Hazardous material screened out by CST technology Such demands are compounded further as environmentally and healthaware public authorities simultaneously seek to deliver quality water services while playing their part in conservation by making best use of their areas’ shared water resources. One council that has successfully used advanced ultrafiltration technology to deliver a high standard outcome for its district is Wakool Shire Council, which draws its water from the Murray River and treats it in the small town of Tooleybuc, NSW, right on the border with Victoria. Working together with CST Wastewater Solutions’ delivery partner Envirotech Water Solutions, Wakool Shire Council replaced the old plant with a new ultrafiltration plant to provide potable water for Tooleybuc’s town water supply. The entire plant was installed in just two weeks of on-site work and achieved results exceeding Australian standards. “It was an outstanding outcome to be able to work with the council to complete the work so efficiently within a narrow time frame. Wakool Shire Council is very happy with the installation, which uses technology widely applicable to the many councils facing similar issues,” said Mr Damien Abbott , Business Development Manager – Victoria, CST Wastewater Solutions. CST’s SFC Screen Extractor “Another big advantage for councils like Wakool is that on-site attendance and maintenance is very low, with only one day a week being required. This produces both cost-efficiency and OH&S benefits,” continued Mr Abbott . The new plant has a capacity of 0.5 MLD (over 20 hours) with a peak flow of 6 L/s. The water is treated for turbidity, colour, protozoa and viruses using CST’s advanced ultrafiltration technology. The technology reduces turbidity from 8 NTU to <0.1 NTU, and colour from 15 to 5. Australian drinking water standards specify that acceptable drinking water needs to be <5 NTU and <15 true colour *, so the Tooleybuc plant well exceeds these standards. “Improving turbidity by over 80 times and significantly reducing the colour to exceed Australian Standards is an excellent result for the project, which is widely applicable to councils and municipalities across Australia,” said Mr Abbott. The Pentair X-Flow ultrafiltration plant installed at Tooleybuc is a new generation of low-pressure membrane filtration technology engineered to produce water from all kinds of water sources using ultrafiltration (UF) and, more recently, nanofiltrati on (NF). X-flow’s strength is the integration of critical process steps to ensure a Full Circle Membrane Technology partnering approach encompassing all key process and operational steps including membrane manufacture, engineering design, installation and commissioning support and ongoing operational support. CST integrates a range of X-flow and other membrane systems that are tailored to the specific raw water quality requirements and treated water objectives for clients. Flood Challenge: Richmond Valley, NSW An upgrade by Richmond Valley Council of its Casino Sewage Treatment plant has paid immediate dividends by withstanding the fury of June’s storms and floods without suffering any polluting spills or odours. The turnkey upgrade – which included retrofitting of fine screening technology by CST Wastewater Solutions – was completed just days before the bad weather along Australia’s East Coast dumped more than 160mm of water on the council region within 48 hours. “The Council couldn’t have timed the upgrade any better. Their foresight and technology upgrade was perfect,” said CST Wastewater Solutions Managing Director Mr Michael Bambridge. “The Northern Rivers District of NSW is one of the most flood-prone areas outside of the tropics, where events like this are likely to occur and reoccur, so the investment in new technologies has already paid off .” The retrofit project – of a type that is applicable to councils and industrial uses throughout Australia and New Zealand – replaces the previous coarse raked screen design with current fine screening technology. This captures more solids to reduce potential blockages in tanks and downstream equipment, while reducing odours by sealing the inlet works and by the installation of new odour control units. The project’s high-efficiency fine screening SFC technology (Screen Press for Channel Installation) is engineered to deliver low-maintenance performance with reduced WHS hazards for municipal and industrial waste water operators. The SFC allows for a much finer level of screening – 5mm compared with typical old systems at 60mm or more – which has led to a significant reduction in solids in the tanks, while producing more efficient treatment with less maintenance. The retrofit also involved the installation of an SDS 20 compactor with two inlets – one for each screen – to dewater screenings to 25-30% dry solids. Each screen has an enhanced design capacity of 250L/s fl ow, providing

   CST Wastewater Solutions packages include proven global and locally manufactured technologies ranging from fixed installations (left) to remote container or skid-mounted portable low-maintenance applications (right). New engineer-and-build water and waste water treatment and recycling packages are being introduced by CST Wastewater Solutions for industries and municipalities that want to lower the cost and complexity of such projects. The design, supply and install packages – incorporating global and locally manufactured technologies proven in use by some of Australia and New Zealand’s leading companies and councils – are aimed particularly at: Councils seeking engineering assistance to develop clear choices and optimum solutions incorporating advanced low-maintenance technologies providing high levels of water purity while reducing maintenance, waste handling and OH&S issues associated with running them. Industries seeking readily constructed or portable, low maintenance solutions for operations particularly in remote, ecologically or environmentally sensitive areas – ranging from resources or agribusiness developments in the country or outback, through to food, beverage, manufacturing and processing plants sharing precious water resources with urban areas. “Rather than presenting such organisations with a jigsaw of disparate collections of technologies and engineering services options for them to piece together, our packaged solutions focus on clear, properly engineered solutions that deliver what they promise. CST offers turnkey solutions based on a known raw water quality and guaranteeing water quality outcomes thus giving user engineers significant confidence in the outcomes and limiting their exposure and potential concerns,” says CST Wastewater Solutions Managing Director Mr Michael Bambridge. “There have been major advances in water quality, water recycling and green energy from wastewater technologies over the last decade, but not all organisations have the in-house expertise these days to realise the benefits. And whereas standard solutions might have been good enough when there were fewer pressures on water quality and demand on water as a shared community resource, today water managers have to design to a much tighter and demanding sustainability brief,” he says. Recycling and green energy technologies in the food and beverage industry, left, CST’s SFC Screen Extractor, centre, and a successful initiative by Goulburn Mulwaree Council involving medium pressure ultraviolet (UV) disinfection supplied by CST Wastewater Solutions for its effluent irrigation scheme, which has conserved potable water. Effective technologies are available and proven – including advanced screening, membrane and aerobic and anaerobic digestion, filtration and reverse osmosis for example – but the best combinations “just can’t be picked off the shelf to fit particular projects. They have to be engineered for local conditions or they won’t deliver on their promise,” said Mr Bambridge, whose company’s projects range from water quality plants for councils throughout Australia to green energy generation and water recycling plants for organisations such as the Bluetongue Brewery, Cadia mining, Frucor, Golden Circle and national dairy, paper and agribusiness companies. Locally manufactured technologies – such as fine screening, for example – are already reducing maintenance and OH&S issues for Australian and New Zealand companies, while CST Wastewater Solutions also represents globally successful technologies including Smith and Loveless, Berson UV disinfection systems and Global Water Engineering water quality and green energy technologies proven in more than 300 projects worldwide. One GWE project recent won a global award from the Institution of Chemical Engineers, IChemE, which represents more than 40,000 engineers globally. GWE water quality technology – which extracts green energy from waste water to turn a problem into a profit – is currently being deployed by the leading Japanese meat processor NH Foods at Oakey Beef Exports in Queensland. The Oakey project not only radically improves waste water quality but also generates biogas (methane) to replace fossil fuels and lessen environmental impacts. Another advanced technology, high efficiency SFC fine screening extractor technology, is currently delivering low maintenance performance with reduced OHS hazards for municipal and industrial waste water schemes. This technology, which also reduces handling of waste, is demonstrating immediate results in one of its recent applications, for the co-joined towns of Harden and Murrumburrah, where it is incorporated into the treatment system improving water quality for a population of approximately 2,000 people. CST Wastewater Solutions’ Managing Director Michael Bambridge, left, who recently installed a GWE combined green energy and wastewater treatment plant for one of Australia’s major global beef processers, Oakey, right, and skid and container mounted water quality technologies for major mining operations. “Many communities and industries – especially throughout regional and outback areas of Australia – face water quality and recycling issues brought about by drought and limited water resources available for drinking, agriculture, product processing and sharing between communities and their industries. “Some such groups have limited access to the technical resources, technologies and application know-how to produce solutions to their issues, which is where packages such as we have introduced can be invaluable.” CST Wastewater Solutions engineering team has a track record of more than 25 years successful project implementation to back its new design, supply and install packages.

Towns like Tooleybuc can benefit from cost-effective ultrafiltration systems to improve water quality Municipal councils all over Australasia are seeking optimum ways to address challenges posed by water resources declining both in quantity and quality under pressure from local populations and the needs of industry and agricultural users. Such demands are compounded further as environmentally and health-aware public authorities simultaneously seek to deliver quality water services while playing their part in conservation by making best use of their areas’ shared water resources. One council that has successfully used advanced ultrafiltration technology to deliver a high standard outcome for its district is Wakool Shire Council which draws its water from the Murray River and treats it in the small town of Tooleybuc, NSW, right on the border with Victoria. Working together with CST Wastewater Solutions’ delivery partner Envirotech Water Solutions, Wakool Shire Council replaced the old plant with a new ultrafiltration plant to provide potable water for Tooleybuc’s town water supply. The entire plant was installed in just 2 weeks of on-site work and achieved results exceeding Australian standards. “It was an outstanding outcome to be able to work with the council to complete the work so efficiently within a narrow timeframe. Wakool Shire Council are very happy with the installation, which uses technology widely applicable to the many councils facing similar issues,” says Mr Damien Abbott, Business Development Manager – Victoria, CST Wastewater Solutions. The ultrafiltration system installed at Tooleybuc, NSW “Another big advantage for councils like Wakool is that on-site attendance and maintenance is very low, with only one day a week being required. This produces both cost-efficiency and OH&S benefits,” said Mr Abbott. The new plant has a capacity of 0.5 ML/day (over 20 hours) with a peak flow of 6 l/s. The water is treated for turbidity, colour, protozoa and viruses using CST’s advanced ultrafiltration technology. The technology reduces turbidity from 8 NTU to <0.1 NTU and colour from 15 to 5. Australian drinking water standards specify that acceptable drinking water needs to be <5 NTU and <15 true colour*, so the Tooleybuc plant well exceeds these standards. “Improving turbidity by over 80 times and significantly reducing the colour to exceed Australian Standards is an excellent result for the project, which is widely applicable to councils and municipalities across Australia,” said Mr Abbott. The Pentair X-Flow ultrafiltration plant installed at Tooleybuc is a new generation of low-pressure membrane filtration technology engineered to produce water from all kinds of water sources using ultra-filtration (UF) and, more recently, Nano-filtration (NF). X-flow’s strength is the integration of critical process steps to ensure a Fill Circle Membrane Technology partnering approach encompassing all key process and operational steps including membrane manufacture, engineering design, installation and commissioning support and ongoing operational support. CST Wastewater Technology packages New engineer-and-build water and waste water treatment and recycling packages from CST Wastewater Solutions are aimed at industries and municipalities that want to lower the cost and complexity of such projects. The design, supply and install packages – incorporating global and locally manufactured technologies proven in use by some of Australia and New Zealand’s leading companies and councils – are aimed particularly at: – Councils seeking engineering assistance to develop clear choices and optimum solutions incorporating advanced low-maintenance technologies providing high levels of water purity while reducing maintenance, waste handling and OH&S issues associated with running them. – Industries seeking readily constructed or portable, low maintenance solutions for operations particularly in remote, ecologically or environmentally sensitive areas – ranging from resources or agribusiness developments in the country or outback, through to food, beverage, manufacturing and processing plants sharing precious water resources with urban areas. Rather than presenting such organisations with a jigsaw of disparate collections of technologies and engineering services options for them to piece together, the packaged solutions focus on clear, properly engineered solutions that deliver what they promise. CST offers turnkey solutions based on a known raw water quality and guaranteeing water quality outcomes thus giving user engineers significant confidence in the outcomes and limiting their exposure and potential concerns, says CST Wastewater Solutions Managing Director Mr Michael Bambridge. *Based on Australian Drinking Water Guidelines Version 2.0 (Updated December 2013)

A water recovery plant designed to target world’s best-practice water reuse standards in the food and beverage industry has exceeded its designers’ high expectations in service at the new Bluetongue brewery in Australia. The waste water treatment and green energy plant at the $A120 million Pacific Beverages’ Bluetongue Brewery in NSW also provides valuable renewable energy for the brewery, reducing its dependence on fossil fuels and ultimately cutting overall energy needs by 15 per cent. The plant – engineered by Australia’s CST Wastewater Solutions in partnership with Global Water Engineering –has achieved all the high environmental performance targets set by Pacific Beverages, a SABMiller/Coca Cola Amatil joint venture, says CST Wastewater Solutions Managing Director Mr Mike Bambridge. Pacific Beverages designed the plant to ultimately have an annual capacity of 150 million litres, while targeting a reduction in water usage to 2.2l / 1 litres of beer produced. This figure is amongst the best in the world and certainly well above the global average of 4 – 5 litres of water to every one litre of beer, says the CEO of Pacific Beverages Mr Peter McLoughlin. Bluetongue MBR Bluetongue control centre The GWE anaerobic technology plant employed at the plant produces sufficient green energy (methane) from its closed anaerobic reactor to power a designated steam boiler and cut the brewery’s overall energy consumption by about 15 per cent. This equates to about 300,000 Mj Mr Bambridge says this the plant indirectly reduces the brewery’s carbon footprint by reducing the brewery’s demands on fossil fuels and the electricity needs for wastewater treatment by using energy-friendly anaerobic pre-treatment technology in which GWE is a world leader. “And the plant produces treated effluent to be safely reused as process and cleaning water within the brewery, reducing by ca. 50 per cent the need for fresh water, thereby greatly contributing to reducing the amount of water typically used to produce a litre of beer.” Highlights of the system’s performance in its first year of service included: The COD removal rates over the anaerobic reactor have consistently been above the design of 85% removal. The same for the biogas production which has been better than theoretical production rates. ca. 1,436 Nm3/d at 80% CH4 at average loading (ca. 2,157 Nm3/d at max loading) The performance of the wastewater plant has enabled Pacific Beverages to be on target to meet its goal to be world’s best practice for breweries in water management by using only 2.2 litres of water for each litre of beer produced This WWTP has leading edge wastewater technologies including anaerobic pretreatment, MBR (Membrane bioreactor) and RO (reverse osmosis) as well biogas reuse. It is a model plant for the future for companies in the food and beverage industry. The design philosophy has been to treat the waste water as a resource from which water and energy can be recovered in addition to reducing the site’s carbon foot print. “This is a landmark achievement of water conservation and green energy production, achieved by combining to achieve the latest versions of advanced and reliable technologies available globally,” said Mr Bambridge. “It demonstrates the technology’s practicality for extensive use not only throughout the Australian food and beverage sector – which involves more than 20,000 companies – but also globally, says Mr Bambridge, whose company employed the latest technologies from a range proven globally by Global Water Engineering, headed by GWE CEO Mr Jean Pierre Ombregt. GWE has built successfully more than 300 plants globally producing biogas as part of the industrial effluent clean-up system, of which more than 75 were supplied with subsequent biogas utilization systems for clients worldwide. Users of GWE technologies extend from the Bluetongue Brewery to global concerns such as Budweiser, Chang, Carlsberg, Coca Cola, Corn Products Int’l., Danone, Fosters, Heineken, Interbrew, Kraft, National Starch & Chemicals, Nestlé, Pepsi Cola, SAB-Miller, San Miguel, Singha, Sunkist and Tsingtao. Many of the latest installations use advanced technologies – including anaerobic pre-treatment of water and aerobic polishing – to enhance water discharge purities while converting waste to methane to be burned to power boiler and hot water systems, for example, or to power generators and permanently replace fossil fuels. On average the removal efficiency of GWE’s anaerobic wastewater treatment installations is as high as 90-95%, easily bringing the organic load down to regulatory discharge standards for most types of wastewater, says Mr Ombregt. Besides the economic advantages of GWE’s anaerobic wastewater treatment, there is also a clear environmental advantage in significantly reducing factories’ carbon footprint. This is done not only by supplying renewable energy from the closed anaerobic reactor, thus reducing or even eliminating reliance on fossil fuels, but also by replacing traditional, open, methane-producing lagoons, and by replacing power-consuming, sludge-producing aerobic WWTPs. “The concept of using wastewater to create green energy is much more widely applicable than often realized. Any factory with a biological waste stream or wastewater with high COD (Chemical Oxygen Demand) can easily use this model to generate energy,” says Mr Ombregt.

A major NSW regional council has introduced a supernatant recycling system into the filtration plant in the town water supply, helping to conserve potable water and providing substantial water savings over the long term. The Bathurst Regional Council recycle system, installed by Ted Wilson & Sons of Blayney using equipment supplied by CST Wastewater Solutions, recovers and disinfects the filter backwash water at the plant. Disinfection of backwash supernatant – clear liquid that collects above sediment – is not widely used in Australia, but can recover up to 10 per cent of raw water supply while also avoiding the need for discharge flows into river systems. Serving a population of about 37,000, Bathurst’s water filtration plant was originally constructed in 1972. Significant upgrades from 1987 to 1994 increased the water treatment capacity from 27 to 60 million litres per day. The filter backwash water, which is a byproduct of the reverse flushing of the sand filters in the filtration plant in order to clear them of sludge, is discharged into the system’s three sludge lagoons, along with sludge from the sedimentation tank. Previously the supernatant from the sludge lagoons was eventually decanted from the lagoons and discharged. The new system involved the construction of a supernatant pumping station and associated pipework to enable the automatic recycling of supernatant from the sludge lagoons into an in-ground well, and then into the first chamber of the rapid mix tank. The recycle stream will not exceed 10 per cent of the raw water flow through the water treatment system. At the present annual water consumption of about 6000 ML, the wastewater to be recovered could be in the order of 192 ML per year. The overall water to be saved is estimated to be 13,000 ML over 50 years. These estimates are based upon average seasonal demand patterns. With the unseasonal summer just past (2011/12), demand has been lower than expected and the water filtration plant has not operated at full capacity. The supernatant currently being recycled is 6 per cent of the plant flow. This will vary with demand into the future. Contractor TWS was required to supply and install two submersible motor pumps for the pumping station at the in-ground well, one being a duty pump and the other a standby. Also installed were an electrical switchboard at the pumping well and other associated equipment, including a level control for the pumps and lifting chains for raising and lowering them for maintenance. A Berson UV disinfection system, supplied by CST Wastewater Solutions, was fitted between the pumping station and the rapid mix tank to disinfect the recycled water from the sludge lagoons before returning it to the rapid mix tank. The system fully disinfects up to a flow rate of 60 L/s and has a variable power control to enable the UV dosage to be adjustable to suit operating conditions. The transmissivity (UVT10) of the UV system is 75 per cent, the TSS is less than 10 mg/L and the performance is Log Reductions: >3.1 Log Faecal Coliforms, >2.0 Log E. Coli, thereby providing very effective protozoa destruction. A PLC/SCADA telemetry system was installed to automatically or remotely control the operation of the recycle pumps and the UV system. The summary of disinfection equipment fitted during the upgrade includes: Berson inline Model IL1000+Summit. Four new-generation Summit medium-pressure high output/efficiency lamps, 2.5 kW per lamp. Autowipe included. Stepless Energy Control (SEC) with variable power matched to the water quality and flow rate. This real time power level control maintains the preset UV dose rate. Turndown is in the 35-100 per cent range, maximising power utilisation. PLC-based UVTronic+ controller. “It’s an interesting project because backwash supernatant disinfection is not widely used in Australia,” said Michael Bambridge, Managing Director of CST Wastewater Solutions. “The advantage is that the method recovers up to 10 per cent of the raw supply, which reduces the demand on the water storage system and avoids the need for waste flows into the river system. “UV disinfection is relatively new. Backwash water potentially contains Cryptosporidium and Giardia, and UV treatment is more effective than chlorination for these two bacteria.” Mr Bambridge said that the new generation Berson SUMMIT lamps have a higher output power than earlier lamps and also, with SEC power control, a longer life – up to 12,000 hours instead of 10,000 hours or even less with the old-type stepped power. Rex Wilson of TWS said, “We chose CST Wastewater Solutions to supply the UV disinfection equipment because we had worked together on previous projects. All went well, as with other work we have done with them. The equipment had been wet-tested by the manufacturer Berson before it left the factory in Europe. “Everything was straightforward and I would recommend CST Wastewater Solutions to other organisations thinking of installing UV disinfection in their wastewater treatment system.” CST Wastewater Solutions is one of Australasia’s leading wastewater solution groups. The company has provided a broad range of quality cost-effective solutions for 25 years, expanding recently to become CST Wastewater Solutions to reflect its expanded scope and now operating from its new combined office and warehouse in Roseville. CST is a member of the Global Water and Energy Alliance, a group of select companies around the world committed to providing solutions in water and wastewater treatment for the recovery of green energy and water. The supernatant recycling project at Bathurst Regional Council was partially funded by the Australian Government’s Water for the Future initiative through the National Water Security for Cities and Towns program.