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Leopold® Clari-DAF® and FilterWorx Systems Featured at AWWA 2010 Conference in Chicago

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Chicago, June 20-24, 2010

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www.xyleminc.com

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Caroline Potter
+1 724 453 2034
Caroline.Potter@xyleminc.com


ITT delivers clean water to Winnepeg with the largest dissolved air flotation treatment system in North America

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Stockholm, April 16, 2010 – ITT Corporation, a global leader in the transport and treatment of water and wastewater, has announced the start-up of the largest dissolved air flotation (DAF) water clarification system in North America. DAF systems are used to efficiently remove taste- and odor-causing algae and other low-density particles from drinking water. The system was installed as part of the treatment process at the new Winnipeg drinking water treatment plant in Manitoba, Canada that supplies 400 million liters of clean drinking water each day.

ITT's Leopold® brand Clari-DAF® system was chosen for the Winnipeg project because of the system's energy efficiency and ITT's extensive experience in DAF and filter installations. The Clari-DAF system floats the matter to the surface by dissolving air into water under high pressure, with the resulting micro-bubbles lifting the suspended particles to the surface, allowing for removal with mechanical scrapers.

"We are extremely proud of this project, not only because of its size, but because it will deliver exceptional water quality to the residents of Winnipeg for decades to come," said John Williamson, president of ITT Water & Wastewater. "This is another excellent example of ITT's leadership in water treatment and our ability to supply complete processes—starting with design and product engineering through installation and commissioning."

The Leopold Clari-DAF system operates in eight basins within the 12,000 square meter Winnipeg plant, and includes mechanical skimmers, saturators, selected piping, compressor packages, pumps, valves, drives and gates, in addition to a complete controls and instrumentation system.

About ITT Corporation

ITT Corporation is a high-technology engineering and manufacturing company operating on all seven continents in three vital markets: water and fluids management, global defense and security, and motion and flow control. With a heritage of innovation, ITT partners with its customers to deliver extraordinary solutions that create more livable environments, provide protection and safety and connect our world. Headquartered in White Plains, N.Y., the company generated 2009 revenue of $10.9 billion.
www.itt.com

About ITT Water & Wastewater

ITT's Water & Wastewater business is a global provider of water handling and treatment solutions for municipal and industrial customers in more than 140 countries. ITT designs and delivers energy-efficient solutions and related services for water and wastewater transport, biological treatment, filtration and disinfection. The Water and Wastewater business employs a global sales network, has manufacturing sites in Europe, Asia and the Americas, and is based in Stockholm, Sweden.
www.xyleminc.com

Press Contact

Caroline Potter
+1 724 453 2034
Caroline.Potter@xyleminc.com


ITT to provide desalination pretreatment for plant in Jeddah, Saudi Arabia

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White Plains, N.Y., March 24, 2010 – ITT Corporation, a global leader in the transport and treatment of water and wastewater, announced it has received a contract to supply a desalination pretreatment system in Jeddah, Saudi Arabia. The contract was awarded by Doosan Heavy Industries and Construction Company, Ltd., the prime contractor for the plant.

The new plant will supply reverse osmosis (RO) membrane treated water to the City of Jeddah beginning in the third quarter of 2011. The reverse osmosis process applies pressure to RO membranes in order to extract salt from seawater, creating high quality, potable water. However, RO membranes are intended for removing only salt and dissolved ions. Seawater also can contain a number of contaminants that can damage the membranes. ITT's Water & Wastewater business will supply Leopold® FilterWorx™filtration systems to pre-treat the seawater, removing the harmful contaminants before they can reach the RO system.

"In many arid regions of the world where the only water supply is seawater, it is important that we offer a viable and cost-effective method of desalination. Leopold filters in combination with a reverse osmosis membrane system provide the solution," said John Williamson, president of ITT Water & Wastewater. "We are pleased to partner with Doosan to bring quality water to the people of Saudi Arabia."

The Jeddah Phase 3 Plant, which is owned by the SWCC, Kingdom of Saudi Arabia, will produce 690 mega liters per day (MLD) of potable water. The 28 Leopold FilterWorx filters consisting of Leopold Type S® underdrain, washwater troughs, penstocks, air blowers and filter media, will pre-treat the source water from the Red Sea.

About ITT Corporation

ITT Corporation is a high-technology engineering and manufacturing company operating on all seven continents in three vital markets: water and fluids management, global defense and security, and motion and flow control. With a heritage of innovation, ITT partners with its customers to deliver extraordinary solutions that create more livable environments, provide protection and safety and connect our world. Headquartered in White Plains, N.Y., the company generated 2009 revenue of $10.9 billion.
www.itt.com

About ITT Water & Wastewater

ITT's Water & Wastewater business is a global provider of water handling and treatment solutions for municipal and industrial customers in more than 140 countries. ITT designs and delivers energy-efficient solutions and related services for water and wastewater transport, biological treatment, filtration and disinfection. The Water and Wastewater business employs a global sales network, has manufacturing sites in Europe, Asia and the Americas, and is based in Stockholm, Sweden.
www.xyleminc.com

Press Contact

Caroline Potter
+1 724 453 2034
Caroline.Potter@xyleminc.com


The Impact of Continuous Sludge Collection in Potable Water Treatment Plants

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In a conventional potable water treatment plant that uses surface water as its source, the treatment scheme usually consists of:

  • Coagulant feed to the rapid mix
  • Flocculation and sedimentation
  • Filtration as the last step to remove insoluble material
  • Disinfection
  • Storage and distribution to the customers

 
Plant personnel usually attempt to remove as much of the raw water contaminant as possible in the clarification step. The contaminant removal is important to optimize the filter operation and achieve the longest filter runs between backwashes and highest effluent water quality. Invariably, operators focus on treating the water source with the right chemical options to oxidize soluble material, adjust pH, as well as coagulate and flocculate the solids so that they settle adequately in the sedimentation basins and do not carry over to the filters.

These typical surface water treatment plants also consist of a solids-handling scheme to process both solids that are settled out in the clarification step and solids removed from the filters during backwash. Since the focus is usually on achieving the highest water quality to supply the consumers, these solids handling schemes and their impact on plant operations can easily be overlooked.

Solids handling can have a major impact on water quality and cost of operation. Some systems allow solids to accumulate in the sedimentation tank, periodically shut them down and then manually clean them. This approach has some drawbacks to consider. As solids accumulate in the basins, the residence time for settling is decreased and could cause additional solids to be sent to the filters. These additional solids are low density solids that will cause a quicker loss of head and require more frequent filter backwashes. In addition, the solids build-up on the bottom of the basins could easily allow anaerobic bacteria to grow beneath the sludge and create septic conditions within the tank. This condition could manifest itself as taste and odor problems, gas generation that could carry solids over to the filters, and may require additional disinfection for the finished water. When removing solids periodically, the operators would prefer to have the maintenance completed during times of low demand, so scheduling can become a problem. This basin cleaning maintenance often requires overtime for labor and a large amount of sludge to handle at one time. All of these issues increase operational cost. The raw water contaminant quantity and coagulant dosage will determine solids removed, amount of sludge build up, and the frequency of shut downs to manually clean the basins.

The alternative to this periodic shutdown and manual cleaning of sedimentation basins is to continuously remove sludge solids with a sludge collector. If the sludge collection system is designed properly and operated correctly, the solids are removed (every hour or every shift or every day) so that the basins maintain their settling capacity. The collection system also eliminates both the potential for anaerobic bacteria growth, and the need to schedule shutdowns involving added manpower cost and handling large amounts of sludge at one time.

Cartagena Plant
The Aguas de Cartagena S.A. E.S.P plant in Colombia treats an average of 4,860 m3/hr (30.8 MGD) through its conventional water treatment plant. The treatment scheme consists of five trains with equal flow and each having hydraulic flocculation, a sedimentation basin, and dual media gravity filters. The source water is from the Magdalena River and stored in a reservoir prior to being pumped into the treatment plant. The water entering the plant contains turbidity from 2 to 5 NTU, color of 30 to 50 Pt-Co, and TOC of 7 to 8 mg/L. The plant uses alum as its coagulant and feeds it at a rate of 60 to 80 mg/L. The plant shuts down four times per year to clean each of the basins. The maintenance shut down requires the plant to take four days working 8 hours/day to clean one basin and put it back into operation. During this time 4,000 m3 (106 gallons) of effluent water is diverted to clean each basin. The sludge is sent to a holding pond for processing through the solids handling dewatering facility.

CT2
In February 2008, the plant installed Leopold© CT2© submerged sludge collectors in Basin #2, one of its five rectangular sedimentation basins. The CT2 submerged sludge collector operates on the simple principle of gravity and removes sludge by taking advantage of a differential head. Water pressure in the main tank forces the sludge through the header collector into the outlet piping, and away to the sludge removal trough. Careful selection of smooth-bore piping for the suction header keeps headloss to a minimum, maintains efficient sludge removal, and low driving head requirements. A simple cable drive moves the suction header across the tank floor at a steady, controlled rate, removing sludge without disturbance.

CT2 Guide

Cartagena Panel
The CT2 header is locked onto the guide rail and is controlled by a programmable operating system. The cable drive pulls the header through the sludge with a positive motion and minimal sludge disturbance, removing the sludge without dilution. This reduces the sludge volume, which in turn means lower thickening and dewatering costs.

To evaluate the system, it was decided to compare the performance of Basin #1 and Basin #2. For the year prior to the CT2 installation, in 2007, Basin #1 effluent averaged 1.71 NTU while Basin #2 effluent turbidity averaged 1.86 NTU. Since installing the CT2 submerged sludge collector in the #2 Sedimentation Basin in 2008, Basin #2 now averages effluent turbidity that is 10% lower than Basin #1's effluent turbidity. The plant has operated Basin #2 for a year without shutting down for maintenance cleaning, while still requiring the usual three-month shut downs for the other four basins.

The filters have consistently operated for 30 hours between backwashing, and filter effluent turbidity readings are less than 0.3 NTU.

The installation of the CT2 submerged sludge collector has resulted in sedimentation and filter effluent water quality improvement, reduced operator attention to the solids handling portion of the plant, and reduced operating cost of producing water. In fact, it has worked out so well that the plant is installing CT2 submerged sludge collectors in two additional basins.