agregat project

Scheduled to come into operation in mid-2008, Fallujah&squo;s first-ever integrated sewerage system is the largest project to be overseen by the US Army Corps of Engineers in Al Anbar Province, and forms part of the extensive reconstruction programme of post-war Iraq.

“Around 6% of Iraq’s 27.5 million population are served by wastewater treatment plants.

The main element of the project is the city’s new wastewater treatment plant (WTP), which has sufficient additional capacity to accommodate a 50% population growth.

Other components of the scheme include the provision of an extensive collection system, a trunk main sewer and associated pumping stations.

The final project cost will be around $85m.

BACKGROUND

Currently, only around 6% of Iraq&squo;s 27.5 million population are served by wastewater treatment plants. Located some 69km west of Baghdad on the River Euphrates, Fallujah ‐ like many of the country&squo;s cities ‐ relies on individual septic tanks. This has often led to raw sewage leaking directly onto the streets or into storm drains, which ultimately discharge into the river. With the Euphrates offering an important source of drinking water to settlements downstream, there are clear problems of contamination.

The project seeks to rectify this issue while providing much needed jobs in areas of high unemployment. Around 450 Iraqis have been working on the project throughout 2007, with a further 250 expected nearer the 2008 completion date.

THE SCHEME

The current programme includes the installation of 30,000m of sewer lines in the south-west of the city, and will initially serve about 3,000 homes. However, this represents only the first phase of an ambitious city-wide system that will ultimately extend to connect all of Fallujah&squo;s households to a central sewer network.

The work is made of 13 separate contracts and involves both city and national officials in addition to the project management team and contractors. Once the project has been completed, these same officials will eventually take over operation and maintenance of the new sewer system.

“The current programme includes the installation of 30,000m of sewer lines in the south-west of the city.”

Two large capacity pumping stations ‐ capable of handling flows of around 150,000m³ per day ‐ have been constructed to pump wastewater from five collection systems to a trunk collection network, which forms the backbone of the new infrastructure.

Treatment at the new WTP follows an essentially conventional approach of screening, biological processing and settlement. On arrival at the plant, influent wastewater will pass into inlet tanks before flowing onto aerated grit and oil removal tanks.

The flow will then pass through aeration tanks towards the settling tanks. Settled solids will be removed for separate disposal, while the effluent is disinfected in a chlorination contact chamber before finally being discharged into the Euphrates River.

To ensure the long-term viability of the new plant and infrastructure, a team of engineers and other specialists are working throughout the project to check the quality of the ongoing construction and promote safe working practices ‐ issues seen as key to the project&squo;s success.

Ultimately, the provision of centralised sewage treatment will bring major benefits to Fallujah, improving public health and reducing pollution to one of the region&squo;s major waterways.

KEY PLAYERS

The project sponsor is the Government of Iraq through the Ministry of Public Works, with project management and ultimate oversight being the responsibility of the US Corps of Engineers.

Construction is being undertaken by Iraqi contractors and a local workforce, with additional supervision from a team of Iraqi engineers.

The Saskatchewan City of Saskatoon is four years into a ten-year expansion programme intended to prolong the useful life of its wastewater treatment plant (WTP) by a quarter century. h20 and wastewater projects are set to account for some C$44m of the city’s proposed 2008 capital budget.

“The overall WTP improvement project has an estimated total cost of C$130m.”

The bulk of the 2008 funding is going towards a new UV disinfection system and filter plant expansion at the city’s facility. The remainder is to be spent on plans designed at reducing sewer backups, improving wastewater collection and mitigating flooding, along with a series of maintenance projects.

The UV system is budgeted at C$13m, with the filter plant upgrade and expansion expected to cost up to C$17m. The overall WTP improvement project has an estimated total cost of C$130m.

In addition, the proposed 2008 capital budget allocates C$2.3m for wastewater collection and a further C$2m to alleviate basement flooding.

Expanding the WTP will allow it to meet higher water quality standards and increase average production by almost 100,000m³ per day. New initiatives on wastewater resulted from heavy flooding in the spring and summer of 2007.

BACKGROUND

Saskatoon formally became a city in May 1906, with a population of 5,000. The city currently has nearly a quarter of a million inhabitants. Located beside the South Saskatchewan River, Saskatoon covers 144km² and includes a large area of parkland along the river.

The WTP was first built in 1906, using steam-driven pumps to draw water into a clay-lined sedimentation basin. In 1910, a rapid sand filtration plant – which remains in service to this day – and electrically-powered centrifugal pumps were installed.

Since these first upgrades, the plant has undergone a series of expansions to meet growing demand with capacity trebling in the last fifty years. The current programme of works is intended to address further growth and changes in regulatory requirements.

WATER TREATMENT

The South Saskatchewan River provides the WTP with its source water. The flow is initially screened before being pumped to the plant where it enters sand filtration and is subsequently dosed with potassium permanganate and ferric sulphate.

Lime is added to reduce turbidity in the clarifiers and radial launders draw off the clear water from the top. Excess floc sludge is back-flushed to the river. The treated water is then dosed with chlorine and fluorine before flowing to the sedimentation tank for filtration.

“The WTP was first built in 1906.”

The WTP currently uses both rapid sand and sand/anthracite filters; the planned work at the filter plant includes upgrading the existing sand beds to dual media.

The new UV disinfection system is necessary to meet lower chlorine standards put in place by provincial and federal authorities. The existing chlorination system must be replaced by 2009 to comply with the Canadian Environmental Protection Act.

After around 30 mins in clearwell storage, the water flows into the city’s distribution system. Process control includes full system alarm, data logging and reporting functions – installed during an earlier improvement scheme in the 1990s – and automatic chemical dosing.

WTP EXPANSION

The ten-year WTP expansion project began in 2004, with the construction of a new sludge handling facility and the relocation of the plant’s electrical towers. This was followed by the completion of a new operations facility, the commencement of a phased upgrade of the chlorination system and the purchase of land designated to host the new maintenance building (with construction beginning the following year).

“Increased pumping capacity will be installed during 2008 at the 42nd Street Reservoir.”

The sludge handling facility was completed in 2006 along with a new pump-house and water intake. Reservoir capacity was expanded during 2007 to improve treated water storage.

In addition to the new UV disinfection system and the expansion of the filter plant, increased pumping capacity will be installed during 2008 at the 42nd Street Reservoir to give greater process control and better circulation of water within the reservoir.

A new water intake is also scheduled for 2008 - at a cost of C$33m - funded by an earlier round of expenditure.

When the project reaches its scheduled completion in 2014, the useful life of the WTP will have been extended by 25 years.

KEY PLAYERS

Saskatoon City Utility Department is responsible for the ownership and operation of the plant and infrastructure. The WTP supplies water to users beyond Saskatoon’s boundaries under a Master h20 Supply Agreement to Sask h20 Corporation.

Health Canada is the official body responsible for regulating water quality; Saskatchewan Environment is the permitting authority. Upgrades to the process control systems were made by Sceptre; Phase 1 improved automation and design and construction services are being provided by Associated Engineering.

The Halong City sanitation project is part of the $120m Three Cities Sanitation Project, an ongoing scheme since the mid-90s to improve the public health of 1.5 million citizens in Da Nang, Haiphong, and Quang Ninh Province (Halong City and Cam Pha).

The Three Cities Sanitation Project aims to reduce waterborne diseases, environmental problems and the adverse effects of flooding and poor sanitation through improved waste management and sanitation infrastructures.

HALONG CITY

Construction at Halong City began in February 2006 and was completed by October 2007. The project involved the construction and installation of a new Sequencing Batch Reactor (SBR) wastewater treatment plant outside of the city at Hon Gai. The project required 80km of drainage channels, 10km of sewer pipes and the construction of three sanitary landfills along with two septic sludge treatment plants (for areas too far from the new main sewer system).

The installation of the SBR involved the provision of 3.5km of pressure sewage pipelines (100mm to 500mm) and eight underground sewage-pumping stations with capacities ranging from 630m³ to 7,000m³ per day along with 10km of gravity sewers. The city authorities were provided with 27 new vehicles for the collection of solid waste and septic sludge. Grants were also made available from a revolving fund so that 11,000 households could install a septic tank.

The Halong City sanitation project borders Halong Bay, a United Nations Educational, Scientific and Cultural Organisation (UNESCO) World Heritage Site, which demanded an even greater need for careful waste control and environmental preservation

CONTRACTORS

The main engineering firm behind the Halong City project was COWI of Denmark, which was responsible for the design, engineering and project management of the entire system while the Danish International Development Agency(Danida) provided technical assistance for the project.

The construction contract for the SBR system was awarded to a joint venture of Biwater Man Lee (BML) and local Vietnamese construction company Constrexim Holdings (Black and Veatch was also involved as a consultant engineer). The contract was awarded by the Urban Environment section of the People’s Committee of Halong City, Quang Ninh Province.

The contract for the SBR construction was worth £3.8m, supported by the World Bank, IDA, IRDB, and the governments of Australia, Denmark and Finland.

SIGRIST process instruments have been used for 60 years to secure the quality of drinking water by measuring turbidity and other important variables. The most important parameters to be monitored with SIGRIST instruments are turbidity, color, UV absorption, DOC, and oil in water. The accuracy and reliability of SIGRIST photometers are proverbial the world over.

TURBIDITY MEASUREMENT

Turbidity is caused in water by mineral or organic solid particles. A light beam passed through the sample will be scattered by these particles. Measurement of the scattered light intensity and determination of the turbidity level therefore provides an indication of the concentration of the solid particles in the liquid.

Studies have shown that there is a clear correlation between turbidity and the number of bacteria in a water sample. The dangers posed by these germs are made even worse by the fact that they can cling to solid particles and thus survive disinfection with chlorine, chlorine dioxide, UV irradiation or ozone. For these reasons, new guidelines call for limits below 0,2 FNU and continuous monitoring of turbidity in drinking water treatment.

Typical applications are:

Turbidity in raw water
Turbidity after flocculation
Turbidity after filtration
Filter-back-flushing
Turbidity after reservoir / before supply to network

ON-LINE TURBIDIMETER AQUASCAT

3 different versions of AquaScat were developed specifically for water treatment: from dirty river water down to filtrated pure water. AquaScat WTM has a measure span of 0 FNU to 4,000 FNU, a resolution of 0.001 FNU, a non-contact measurement and an automatic adjustment on demand. AquaScat HT has a resolution of 0.1 FNU, a non-contact measurement and is perfect for measurement of high turbidity (e.g. raw water). AquaScat P has a closed flow cell and is used for measurements under pressure (e.g. sample with high content of gas).

COLOR DETECTION IN WATER TREATMENT

The detection of color in water treatment is particularly important wherever surface water with high humic matter loading is treated. If the humic substances are not removed from the water right at the start with flocculation and filtration, it is possible that hazardous trihalomethanes will be formed during disinfection with chorine.

The detection of color and hence of the humic matter concentration is employed in the raw water or following flocculation for control of the flocculation process. It is also useful following filtration as a final check on the decoloration process.

UV ABSORPTION

Harmful substances may be present in water in either undissolved or dissolved form. Just as turbidity detection is used to measure the total solids content, UV absorption detection at a wavelength of 254 nm can be employed to measure the total content of dissolved organic matter.

Studies have shown that, for most applications, a linear correlation exists between the UV-absorption and DOC (dissolved organic carbon) values. This means that UV absorption measurement provides a continuous on-line indication for trend analysis of the DOC figure without time-consuming laboratory checks.

COLOR MONITOR VIS/ UV ABSORPTION MONITOR COLORPLUS

The ColorPlus is built to accommodate up to three different light sources in the UV and VIS ranges. Depending on the required wavelength, a mercury bulb (UV light) or up to three LED’s (VIS light) are installed. The ColorPlus can be calibrated in E/m, Hazen, EBC etc. A combined UV absorption/ Hazen color measurement is possible, too. Like all SIGRIST process instruments, the ColorPlus exhibits the high measuring stability and accuracy afforded by the dual beam measuring method.

For the measurement in water treatment a PVC bypass flowcell (path length of 100mm or 50mm) with compensation glass can be used. The compensation glass is used for calculating and compensating window contamination. This will prevent reading falsification and reduces the need of maintenance.

Another feature of ColorPlus is the possibility of turbidity compensation at a second wavelength, if this can disturb the absorption measurement, e.g. in raw water application.

ITT Industries is the world’s premier fluid handling company. We are the leader in the manufacture, service and repair of:

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SUBMERSIBLE N-PUMP SEWAGE PUMP

The submersible N-Pump - with its unique open self cleaning channel impeller, the N-Pump enables sewage to be continuously pumped with sustained energy efficiency. This can result in energy savings of up to 50% over conventional pumps. A true innovation in the field of wastewater treatment, the N-pump was named Pump of the Year at the 1999 Processing Pumps & Systems Awards ceremony sponsored by the British Pump Manufacturers Association.

PUMPSMART PROCESS PUMP CONTROL SYSTEM

The PumpSmart™ commercial and residential pumping solution - significantly lowers life cycle cost for your fluid handling system. It will not cavitate, and will not run dry. The PumpSmart™ Process Control System was voted one of the Top Five Innovative Products of 1999 by the readers of Flow Control Magazine.

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ESP-Plus, HSS (Hydraulic Selection System) and FLYPS are leading web-based interactive tools for specifying fluid handling systems and products.

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Endress+Hauser is a world-leading manufacturer of high quality, reliable measurement instrumentation for the water industry and other environmental arenas. Our product range is continually evolving and expanding to provide accurate measurement across the parameters of level, flow, analysis, temperature, pressure, data logging, recording and process solutions. We are now able to supply the majority of instrumentation required on most water and wastewater sites. Our product range is backed by excellent service, maintenance, life cycle management tools, product / installation support and calibration.

STAMOLYS COLORIMETRIC ANALYSERS

Designed for automatic unattended continuous operation, our Stamolys colorimetric analysers are essential for the optimisation of plant efficiency. Low maintenance with a modular design, the Stamolys provides reliable measurement of ammonia, nitrite, phosphate, aluminium, calcium in brine, chlorine, chromate, copper, hardness, iron, manganese, silicate and sulphide. In addition, other measurements for nitrate, SAC (BOD, COD, DOC and TOC) can be made utilising UV technology, removing the need for ‘wet chemical’ technology.

LIQUISYS M RANGE OF ANALYSERS

The Liquisys M transmitter provides safe and reliable measurement of pH/redox, conductivity, dissolved oxygen, turbidity and residual chlorine.

Its sensor check system provides continuous health checks on the sensor and self-diagnostics for signal sensor failure. This provides predictive maintenance prompts to reduce unscheduled downtime and costs.

A vast range of measurement sensors and a modular range of installation assemblies for flow through and dip applications are available. The range extends from single and multi assembly sensors through to complex self-cleaning and calibrating assemblies.

PROline PROMAG ELECTROMAGNETIC FLOWMETER

Endress+Hauser’s PROline Promag range of electromagnetic flowmeters have been optimised for the water industry. The Promag 50 is ideal for standard applications, whilst the Promag 53 is for high performance applications. Optimised sensors, lining options, 4-line display and fieldbus communication complete the new Promag range. New configuration, verification and service software offers the user individual support, from facility planning right up to operation and maintenance. High accuracy is maintained in all sizes of nominal diameters from 2mm up to 2m, with all units calibrated on the Endress+Hauser calibration rig.

PROSONIC ULTRASONIC LEVEL MEASUREMENT

The Prosonic range of non-contact ultrasonic devices is ideal for a wide range of applications, from simple continuous point level measurement to open channel flow measurement and pump / screen control. Prosonic offers a measurement range of up to 70m and the option of up to five relays and Profibus connection. Our Prosonic M is supported by the powerful Time of Flight software tool (ToF Tool) for simple configuration, diagnosis and documentation of the measuring point.

LIQUI-PORT 2000 PORTABLE SAMPLER

The Liqui-Port 2000 portable water sampler is lightweight yet robust, offering increased mobility. It has the advantage of compact construction and a low power consumption, saving users both time and money. The sampler works using a peristaltic pump, incorporating rinse functions for the suction hose and swift changeover of sampling modes, ensuring efficiency and measurement integrity throughout the process. Ideal for use in remote locations, the Liqui-Port 2000 is battery operated and so doesn’t require a power supply. The lower compartment can be separated, sealed using an extra lid and transported individually for maximum versatility.

Endress+Hauser recognises the importance of ‘cost of ownership’ and offers a range of value added services to support end users in the management of their assets. These services include traditional service, product / industry / application support, installation and commissioning services, training and full maintenance packages. We provide full turnkey engineering of fieldbus installations, control systems and data acquisition and transfer facilities.

Reap the benefits of our full product range and excellent added value services!

Savannah picks InfoWorks for city-wide model

17 December 2007: The City of Savannah’s h20 and Sewer Bureau has chosen InfoWorks from Wallingford Software to meet its modeling needs.

Both the sanitary sewer and water supply versions of InfoWorks are being used. “We selected InfoWorks from Wallingford Software based on an evaluation of the water and sewer modeling software available in the market. This was the best one to fit our needs,” said h20 & Sewer Engineering Director Abe Ghazi. A particular requirement was to choose a dynamic system, he added. “We are going to be using InfoWorks to model both the water and sewer systems for the City of Savannah.”

The software has been installed and preliminary sets of data have been imported. “We are adding to it and completing the model,” said Mr Ghazi. Parts of the system are already running, though the software has not yet been fully implemented. “We haven’t had any problems with it - it is running well.”

Savannah is located in Georgia in the southern USA. Its h20 & Sewer Bureau is a municipal, government-based, organization serving residents, businesses, and visitors. The Bureau’s work is vital to meeting the needs of a growing community and overcoming the challenges of ageing infrastructure.

The Bureau is made up of an environmental affairs section, as well as four departments, including h20 & Sewer Planning & Engineering (WSPE), which is headed by Mr Ghazi. The department will be using InfoWorks to help in a variety of roles, including managing capital improvement projects, maintaining an inventory of water and wastewater systems and keeping as-built plans up to date. Technical support is provided to the other departments within the Bureau. The WSPE is also the local enforcement agency for the review and approval of all water and sewer construction plans and specifications to ensure full compliance with federal, state and local rules, regulations and ordinances.

At a press conference held in his office recently, Dr Hashem Yamani, Minister of Commerce and Industry and Chairman of the Saudi Organization for Industrial Estate and Technology Zones (SOIETZ), signed contracts with the International Company for h20 Distribution (Tawzea) for the management of water services projects benefitting three industrial cities.

These projects are unique as they provide comprehensive water services while meeting all the environmental and water needs of the industrial cities through ROT (Rehabilitate, Manage and Transfer) contracts. This is the first such move in the Middle East. Namely, the projects are:

The ROT project for potable water facilities in Jeddah’s 1st Industrial City
The ROT project for potable, sewage, irrigation, and industrial water in Riyadh’s 2nd industrial city
The BOT (Build, Operate and Transfer) project for potable, sewage, irrigation, and industrial water in Gassim’s first industrial city

Minister of Commerce and Industry Dr Yamani said the projects are in line with SOIETZ’s strategy to privatize water services within the industrial cities to become integrated entities, adding that more water contracts for industrial cities in Dammam and Al-Ahsa are on the way. SOIETZ is currently revamping operations within the industrial cities in the hopes of modernizing services.

Attending the signing was Dr Tawfiq al Rabiah, General Manager of SOIETZ. “The signing of the water services privatization contracts is part of a grand plan we are implementing at SOIETZ to upgrade services within industrial cities in the hopes of overcoming obstacles faced by industrialists and creating model industrial zones,” commented Dr al Rabiah. “With today’s signing we are embarking on a major regional undertaking for the future of our nation, and as such I am pleased to witness the gradual evolution of our industrial cities as they develop their infrastructure to meet the growing needs of local industries,” added Dr al Rabiah.

The International company for h20 Distribution (Tawzea) is one of the first national companies to provide water services and facilities management in a comprehensive and integrated method. It is a 50/50 percent joint venture between Amih20, a subsidiary of the Saudi Arabian Amiantit Company specialising in water management projects, and the Saudi Company for Industrial Services CISCO. The new company combines Amih20’s global expertise in water management projects, and CISCO’s expertise in services management in industrial cities. While at the present time the focus is on providing these services in the industrial cities, Tawzea looks forward to expanding the company’s future in the management of water services to include the residential and industrial sectors.

Accordingly, Tawzea plans to offer its services in the area of BOT water, water treatment and sewage systems, and the company is also planning to expand its range of operations to include gas distribution networks and residential networks within cities.

For his part, Mohamed al Rehaily, CEO of Tawzea estimated the construction and operating costs of these projects to exceed US$800 million during the 30-year contract life span. Tawzea will meet all the water needs of the first industrial city in Jeddah, the second industrial city in Riyadh, and the first industrial city in Gassim covering the water system, irrigation, sewage and industrial water treatment.

The International Company for h20 Distribution (Tawzea) is a leading Saudi company providing water services and facilities management in a comprehensive manner. Tawzea is a partnership equally divided between Amih20, a subsidiary of the Saudi Arabian Amiantit Company specializing in water management projects.

The Cherokee County h20 and Sewerage Authority (CCWSA) in the southern US state of Georgia is due to begin advanced modeling work using Wallingford Software’s InfoWorks WS solution after eight successful years using its companion solution, InfoWorks CS.

The Authority is based in the City of Canton, population 200,000, and provides water to most of the county outside the city limits - a customer base of 65,000-plus. There are several river basins in the county, with the main one centered on the Etowah River.

The CCWSA cannot raise taxes, is not a part of Cherokee County government, and does not receive any tax revenue. The Authority is a public not-for-profit government entity tasked with providing drinking water and sanitary sewer services to Cherokee County.

Corey Ghorley, h20 Model Specialist at Cherokee County explains that the Authority began using Wallingford solutions in 1999 when its then engineering consultant PBS&J was commissioned to choose water and wastewater network modeling solutions, which the Authority would then purchase.

Mr Ghorley explains: “The consultancy undertook research into various possible solutions and came to the conclusion that InfoWorks was best suited to what we wanted it to do”. Work began with the consultancy incorporating the GPS point data that the Authority provided into the model; then one of the key figures at the consultancy, Jeff Hooper, joined the Association and the modeling work transferred in-house.

The early work focused on InfoWorks CS, as it was assessed as more critical, and on creating a sophisticated model of the county’s wastewater infrastructure. This was undertaken within the Authority’s GPS and GIS department, where crews are commissioned to obtain GPS data on the features of the network - highly-accurate positions of key elements such as the 350 miles of sanitary sewers, inverts and manholes, are recorded and input into the model.

Because the County is in the foothills of the Appalachian Mountains, the elevation of the infrastructure varies from 900ft to 1300ft at the northern end of the area. On the wastewater side the Authority is fortunate that most of the flows reach the treatment works by gravity. However, the model has to include data on the various pump, booster and lift stations in the system. These are all connected to the Authority’s SCADA system, which provides real-time data on the infrastructure that can be incorporated into the model to undertake real-time simulations.

The Authority is currently using the model to assess any infrastructure problems that may arise. The model is also valuable for simulating the addition of proposed new developments, allowing the Association to check whether there would be any adverse effect on the system. “It has been a godsend to us,” Mr Ghorley confides.

Field crews have been following a similar process to that already undertaken for the InfoWorks CS model, tracking pipelines and hydrants and creating real-time GPS location data to survey-grade accuracy. Work on the basic data collection and validation process is now nearing completion and the Authority is on the verge of running a simulation. To date, 570 miles of pipes have been GPS located, and data on booster stations and tank reservoirs has been input.

The initial aim is to gauge the demands on the infrastructure against the amount of water available. From this the intention is to move into infrastructure maintenance, using the model to assess which elements of the system might need to be replaced.

The current demand on the system is estimated at 22MGD, and the treatment works can abstract up to 36MGD from the Etowah River, so the initial assessment is that the capacity is ample to meet current needs. However, the area is listed as fast growing so the Authority has had to move to proactive modeling of potential future demand to ensure that the capacity continues to be sufficient.

Mr Ghorley notes: “This was very helpful. I believe training in-house works out better for us, as it was one-on-one. We are a relatively small department, with just a couple of people working on the model, so it was extremely useful.”

On the InfoWorks CS side, the Authority had sufficient data to be used in the simulations, with the InfoWorks WS training utilizing both in-house and test data. “It worked well and it was really easy to learn,” Mr Ghorley disclosed.

Loch Fyne Oysters Ltd has chosen two Hanovia medium pressure UV disinfection systems for its oyster farm in Loch Fyne, Cairndow, Scotland. The UV systems, which were installed by Barr and Wray, destroy harmful E.Coli bacteria from its oyster and mussel depuration tanks. Each UV chamber treats up to 150 m³ water per hour.

According to a spokesperson from Loch Fyne Oysters: “The Hanovia units were recommended to us by Barr and Wray because of their 99.99% log reduction of E.Coli, their robust, stainless steel construction, their ease of installation and easy maintenance - including easy UV lamp replacement and daily cleaning with a manual wiper - and low running costs. We also find the digital run-time read-out very useful, and the price was very competitive.”

Hanovia UV systems can be used in farms and hatcheries to treat both incoming and recirculation water, allowing flexibility in the choice of site and a rapid payback for farmers. UV is ideally suited for this application as it uses no chemicals and does not create by-products which would harm the stock, or other aquatic life, on discharge.

Unlike other treatment methods, UV also avoids the expense of complex monitoring systems involved in adding and removing chemicals before the water reaches the stock. In addition, it does not alter the pH of the water. Indeed, UV is the most economical disinfection technique that can be used in aquaculture.

Maintenance of the systems is restricted to the replacement of the UV lamps every 12 months, a simple operation that can be carried out by on-site staff. An automatic or manual wiper can be fitted over the quartz sleeve which surrounds the UV lamp to prevent the build-up of any deposits, ensuring maximum levels of irradiation at all times.

A significant feature of Hanovia’s systems is the Photon control panel which displays a range of useful functions such as flow rate, UV dose and intensity. It is capable of logging up to one year’s performance data, which can be downloaded to a PC through an RS232 port. Linked into a central computer, the control panel can also be operated remotely, and allows the system to operate around the clock.

To date Hanovia has installed over 300 aquaculture systems in 14 countries around the world. Applications include water treatment in hatcheries, fish farms, shellfish depuration tanks and fry rearing tanks, as well as treating re-circulation water in marine parks and aquaria.