Several attractive filtration performance attributes are provided when active washable fibres are incorporated into a water filtering media, such as the Fabric Media water filtration technology.  There are process and economic advantages compared to the more traditional media bed filtration techniques, such as sand filters, and surface filters such as micro membrane filtration.

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An 18 month pilot plant study was conducted in Western Australia involving 2 columns of anthracite of different bed depths and 2 columns of granular activated carbon (GAC) of different particle size were run in parallel as primary filters. The performance of each of the columns were evaluated including organics reduction (dissolved organic carbon (DOC), UV absorbance at 254nm, biological dissolved organic carbon (BDOC), and assimible organic carbon (AOC)), chlorine demand and total trihalomethane formation potential (TTHMFP). Each of the filtered waters were compared with the feed water and  analysed regularly under varying operational conditions including MIEX® and enhanced coagulation feed water, empty bed contact times (EBCT) of 8 and 16 minutes, chlorinated feed water, and chlorinated backwash water.

During the pilot plant study the GAC filters outperformed the anthracite filters with superior reduction of organics, lower chlorine demand and lower TTHMFP, with similar run times and filtered water turbidities to the anthracite filters. Chlorinated feed water significantly impacted on the filters performance and chlorinated backwash water slightly decreased filter performance. The optimum operating conditions were using the slightly coarser GAC filter (no head loss issues) at a 16 minute EBCT, however doubling the contact time did not double the performance. Filtering through GAC reduced the BDOC and AOC levels to produce biologically stable water. Biomass studies of the media and the backwash water from each of the filters indicated a higher biological density on the GAC filters compared to the anthracite filters.

The adsorptive capacity of the activated carbon combined with the ability of the carbon to biologically regenerate ensured superior performance (compared to the anthracite filters) and prolonged bed life for organics reduction. Further work will extend the project to examine full scale dual media primary filters using GAC in place of anthracite.

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Calculating the LifeCycle Cost (LCC) of a pumping system has until recently been almost impossible due to the complicated mathematics required. Which PumpTM has revolutionised the industry with their new online LCC software offering end users the ability to accurately calculate their LCC based on real application information.

This article briefly explains the theory behind Which Pump’s LCC method.  It then walks through a LCC example illustrating the types of information required and briefly explains the results you would expect, demonstrating to the reader how real cost savings can be achieved on their pumping solutions.

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United Water is faced with the impending replacement of 20 turbidity analysers over the next two years. Consequently, we set out to determine the most appropriate analyser for the purpose of measuring turbidity of filter outlet and treated water.

Traditionally these instruments have been ranged 0 to 2 NTU which provides suitable accuracy and resolution around the nominal measurement range 0.1 to 0.2 NTU while having enough ‘headroom’ to providing important data on non-conformances. This range became the first specification for the test requirements. Our QA dictates accuracy and some requirements for calibration. These resulted in the specification used in this test.

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Dealing with stratification within water supply reservoirs is a common problem for urban water authorities. Failure to identify and control stratification can compromise water treatment operations, meeting regulatory standards, customer expectations, environmental flow releases and potentially isolate an affected reservoir from a supply system.

In recent years, Central Highlands Water (CHW) field staff have undertaken stratification monitoring to identify the early onset of stratification and developed operational response procedures that introduce appropriate control measures to avoid potential impacts and minimise any adverse affects.

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In common with other water authorities, Barwon Water relies heavily upon harvesting water from catchments both with & without on-stream storages. A significant percentage of Barwon Water’s yield is derived from tributaries of the Barwon River which have no discernable storage and have traditionally required close operator attendance to derive maximum yield.  This close operator attention stems from the need to provide environmental flows as provided for by Bulk Water Licences via the manual operation of timber weir gates on the river diversion weirs.

Over the past few years, the focus on transforming our series of manually controlled diversion weirs into an automated system has grown from the need to better utilise our operators limited time, to one of ensuring the maximum yield is derived whilst maintaining the environment.

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The water transfer capacity of the O’Shannassy Reservoir outlet mains had gradually reduced from 335ML/day to 215ML/day since 1965.

The loss in pipeline capacity has been attributed to a build-up of iron-manganese slime on the pipe walls, measuring between 5-10mm in thickness.

When O’Shannassy Reservoir is full, the lost capacity spills into the O’Shannassy River and can only be recovered by pumping out of the Yarra River at Yering Gorge, 40kms to the west, and into Sugarloaf Reservoir.  This water is then filtered and disinfected at Winneke Treatment Plant at some considerable cost.

Therefore, pigging the main was identified as an economical way to improving capacity, whilst reducing intake from Yarra River and deferring pipeline duplication.

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While population growth and industrialisation of the third world continue to boom, our most precious resource is under threat.   Already limited to a meagre 0.007% of the total water on earth for human use, contamination of many fresh water supplies is further reducing the net available water for safe human consumption.   Uneven distribution of this fresh water across the globe subjects many countries, including Australia to a point of near constant water shortage.

To ensure supply meets growing demand, many technologies have been developed to treat saline water and wastewater of industrial and municipal origin to a potable quality.   Intensification of traditional biological wastewater treatment systems with Membrane Bioreactor (MBR) processes with (or without) RO final treatment is increasing capacity and greatly improving discharge quality for industrial and domestic re-use, while desalination technologies such as Multistage Flash (MSF), Multiple Effect (MED), Vapour Compression (VC) and Reverse Osmosis (RO) have evolved to provide more economically viable treatment methods for sea water.

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The Eastern Irrigation Scheme (EIS) is a joint project between Topaq Pty Ltd and Melbourne Water Corporation (MWC).  The EIS operates under the brand Topaq, a wholly owned subsidiary of Earth Tech.  Topaq will own and operate the scheme for 25 years.  Under the partnership, Earth Tech designed and built an ultra-filtration treatment plant and a 60km pipeline network to supply and distribute Class A recycled water to over 60 customers in and around the Cranbourne area.  The Interim Treatment Plant (ITP) is Australia’s largest recycled water ultra-filtration treatment plant for the treatment of Class C water.  It has a capacity of 30 ML/day of Class A water for irrigation and third pipe use.  The annual demand is approximately 5,000ML.  Individual customer demands range between 1 and 400 ML per year.  The EIS recycles approximately 3.5% of the treated water from Melbourne Waters Eastern Treatment Plant (ETP), contributing significantly to the Victorian Government’s target of 20% water recycling by 2010.

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Rouse Hill Recycled Water Plant (RWP) has been producing recycled water for the largest residential re-use scheme in Australia since September 2001. During the evolution of the recycled water process train, the plant production team has learnt a lot about how to reliably operate a sewage treatment plant in order to achieve quality feed water to the recycled water disinfection process units. Chemical use, trade waste inflow, aeration patterns, storm flow, oxidants, drought and power failures all have significant impacts of the reliable production of recycled water. This paper details how Rouse Hill RWP has evolved over the past 5 years and the special requirements of an STP that is specifically designed for large scale recycled water production.

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“…water should be judged by its quality and not its history.”
Prime Minister John Howard, CEDA Luncheon Address, Sydney, 17th July 2006.

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Western Australia has numerous sources that are high in natural organic matter (NOM).  During disinfection, the reaction between NOM and chlorine can cause problems in achieving effective disinfection, whilst minimising undesired disinfection by-products such as trihalomethanes (THMs).  Bench-scale laboratory experiments have enabled THM formation to be predicted through the development of empirical models for individual sources.

Through the use of the empirical models, operators were able to optimise the chlorine dose rates.  However, some distribution systems require further minimisation of THM concentrations.  This was achieved through the installation of a recirculation and aeration device providing a novel and cost effective solution to volatilise THMs.  Aeration through spray nozzles dissipates the volatile THMs, leading to a 40 to 70% reduction in concentration.  This novel concept will provide water utilities with a new option in maintaining THMs well below the Australian Drinking Water Guideline (ADWG) health value whilst longer term treatment options are considered.

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The raw water sourced at the Warrnambool Water Treatment Plant (WTP) is a combination of approximately 10% ground water and 90% surface water from the Gellibrand River and two of its tributaries in the Otway forest, a pristine closed catchment (Johnstone & Johnstone, 1993). The water, generally low in turbidity (average 5.86) with an average color of 87 TCU, is piped approximately 81 kilometers to Warrnambool either directly or through a series of storages. Whilst the physical characteristics of the water are excellent, periodically, large abundances of phytoplankton and in particular filter clogging algae are present in the water. In March of 2006, a Dissolved Air Floatation (DAF) cell was commissioned at the Warrnambool WTP; this paper will compare and contrast the ability of both the existing clarifier and the DAF cell in removing the phytoplankton before it reaches the filters.

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A number (12) of powdered activated carbons (PAC) were jar tested in natural raw water containing a commercial spike of MIB and geosmin and their performance for reducing these compounds was evaluated. The PACs tested came from a variety of suppliers, raw materials, activation methods and countries including steam activated coal, wood and coconut; and chemically activated wood.

Each of the carbons (except Acticarb PS1300) had the same iodine number (a measure of adsorption capacity) and were analysed under the same conditions including a 15 minute contact time. Of these carbons the Australian steam activated coal carbons, Acticarb PS1000 and PS1300 had the best removal efficiencies. The Acticarb PS1300 was the only carbon with a higher iodine number, however this increase in adsorptive capacity for iodine was not proportional to the increase in adsorption for MIB and geosmin. For all of the PACs tested, the geosmin was more easily reduced than the MIB. Contact time, raw water character and PAC character all influenced the PAC’s ability to reduce MIB and geosmin.

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The 2005 Kwatye (Water) Prize provided an outstanding opportunity to investigate an alternative treatment process to remove natural organic matter (NOM), that generally colours raw water supplies, without the need to add metal salts such as aluminium sulphate.

The Australian experience in reducing colour is largely through the use of one or more conventional treatment steps such as coagulation, flocculation, sedimentation, flotation, media or membrane filtration. The difficulty with these conventional processes include limited removal of the NOM leading to the production of disinfection byproducts, a continued supply of food for the production of biofilms in distribution networks, increasing the disinfectant demand and the need to introduce chemicals such as aluminium salts into the treatment process.

Nanofiltration has been used to deliver finished water with low NOM, and consequently colour, in various countries throughout the world. Membrane technology has provided another set of tools to deliver safe drinking water to our communities. The Kwatye (Water) Prize provided the opportunity to visit researchers, membrane manufacturers and water treatment plants in USA, Scotland, and Europe to learn from their experiences.

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Industries such as wineries and boutique food manufacturers are frequently being established in smaller towns and are capable of generating relatively high-strength waste streams.  With continual external pressure for Water Authorities to treat such industrial wastes, key steps need to be taken to manage the additional loading.

As well as assessment of predicted loading data and subsequent updating of infrastructure, preparation and ongoing monitoring is critical to minimise unwanted environmental and social impacts.

This paper focuses specifically on the planning, industry collaboration, as-well ongoing operational controls for BOD and odour management at the Myrtleford WWTP during the 2006 wine vintage period.

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The Western Treatment Plant treats more than half of Melbourne’s sewage.  The plant comprises a number of large lagoon systems.  Two of these lagoon systems were augmented and upgraded as part of an Environmental Improvement Project to reduce nitrogen loads on Port Phillip Bay.  The most recent upgrade was on the 25 West Lagoon system and involved the construction of a 180 ML/day activated sludge plant within the lagoon system.

This paper discusses the start-up, commissioning and performance in the first year of operation for the 25 West lagoon and 25 West activated sludge nitrogen removal plant upgrade.

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This paper focuses on the waste minimisation achievements of Bulace Dyeing, including dye bath recycling and reducing salt loads in support of Central Highlands Water’s effluent reuse objectives.

An explanation is given of the various risks associated with trade waste resulting from the dyeing of textiles, with an emphasis on mitigation techniques and technical solutions.

Wastewater recycling and potable substitution is discussed throughout the paper, with an explanation of pre-treatment and water handling systems. Chemical substitution of sodium and chloride salts with potassium sulphate and potassium carbonate is a key message.

With reference to an article in the September edition of the Australasian Textile and Fashion Magazine, the paper reinforces the importance of responsible trade waste management and demonstrates value to business and the environment as a whole.

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Cyclone Larry, and in fact any natural disaster will more than likely result in reticulated power loss, resource problems both human and physical.

The basis of this presentation is to learn from deficiencies in disaster planning for water and sewerage as a result of a severe cyclonic disaster and to make other Councils and Governing Bodies aware of issues that arose with Cyclone Larry in the Johnstone Shire and steps that may be of benefit for future disaster preparation.

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Staff from the sewer operations group often has to educt from sewer pumping stations to enable pipe relining/rehabilitation or emergency repair works to be undertaken on sewer rising mains.

It was identified that the eduction process could be sped up and made quieter to be more efficient and less disruptive. Field staff designed and built a portable electric powered submersible pump with a capacity to deliver 60 litres per second.  This was operated with a three phase power switchboard, connected to either the sewer pumping station or a portable generator.  A “y” junction was developed to deliver flows more quickly into two trucks at once.  The submersible pump has reduced tanker spill times by 60 – 70%, and halved the number of tankers required, thus saving almost 50% of cost for the utility.

In addition, site noise has been significantly reduced through the use of an electric pump and avoiding the need for tankers to run their engine continuously whilst using their onboard vacuum pump. This influences greatly on the environment with less pollution due to emissions and lower noise level to keep the public happy. As we now avoid the presence of several tankers to be around the site, OHS issues become a lesser risk. Traffic Management is further optimised and the lower potential for failure provides overall satisfaction and less stress on field crews.

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In the mid 1990’s Hamilton City Council (HCC) made a decision to trial a new locally supplied Porous Ceramic Dual Media (PCDM) filtration system, at their Water Treatment Station (WTS). After positive results from the trial unit, HCC proceeded in the full refurbishment of an existing conventional sand filter to the PCDM system.

Intensive monitoring of water quality and filter performance of the initial refurbished filter, confirmed that the installation of the PCDM technology had optimised the filtration process by increasing filter capacity and run times between backwashing with no degradation to filter water quality. Since that time, HCC has implemented an ongoing programme to optimise the filtration process by refurbishing the remaining conventional sand filters to the PCDM system.

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This paper highlights the processes employed by Campaspe Asset Management Services (CAMS) in the identification and assessment of an alternate flocculant/coagulant for the de-watering of sludge post Autothermal Thermophyllic Aerated Digestion (ATAD) at the Bendigo Water Reclamation Plant (WRP).

Specifically, the paper outlines the rationale behind the replacement of the non-organic product ferric chloride with the organic product Magnafloc 1597. The alternate organic product Magnafloc 1597, traditionally used in the sugar refining industry was as yet un-trialled in Australia with ATAD sludges.

Ferric chloride, used for six years at the Bendigo site, created ongoing issues for operational staff with safe use and storage, effective conditioning of sludges pre-de-watering, cost and end product uses.

Both chemicals were trialled in over several months. The results of this trial allowed for the replacement of ferric chloride with Magnafloc 1597 as the sludge conditioning agent. Improvements were realised through a more efficient treatment of sludge, safer work environments and a more sustainable end product.

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