Chemical feed pump provides reliable metering with minimal maintenance
Problem: Jericho Water District on New York’s Long Island pumps most of its water from wells and was struggling to control corrosion in the pipes. That made it difficult to sustain accurate pressure and water speed.
Solution: The district installed an Encore 700 simplex pump from Cleanwater1 in a new pump house. With a 2-inch diaphragm and robust motor-driven pulley drive, the pump has fewer parts and needs less maintenance. After successful performance testing, operators added more of the pumps to the distribution system.
Result: The low-maintenance pump saved time, reduced operating costs and provided reliable and efficient operation with minimal system vibration. It enabled the operating team to manually and smoothly adjust eccentricity during operation. 855-669-3845; www.cleanwater1.com
Wastewater reclamation plant improves chemical dosing
Problem: The Southwest Water Reclamation Facility in Cape Coral, Florida, pumps an average of 7 mgd. To combat algae buildup, the facility used motor-driven diaphragm pumps to dose sodium hypochlorite. The pumps were effective but required frequent maintenance and often experienced bleach leakage that damaged pumps and fittings, and crystallization that interrupted flow and wasted energy.
Solution: The plant team adopted SEEPEX Intelligent Metering Pumps to provide precision dosing with ultra-low pulsation. An integral drive accepts feedback from a flowmeter for process control.
Result: The pumps have required zero maintenance in 24/7 operation. The constant flow from the pumps greatly reduced on leaks caused by pressure fluctuation, according to Marcus Papp, maintenance supervisor. The need for pressure regulators and check valves has been removed. 937-864-7150; www.seepex.com
Screw blower selected to optimize process control
Problem: The Medford (Wisconsin) Wastewater Treatment Plant had 1970s aeration blowers and was changing to ammonia control. The blowers had a limited control range, leading to over-aeration and limited process controllability. The machines were not as efficient as the newer screw blowers.
Solution: The city worked with an engineering firm to design an optimized control solution using Kaeser high-efficiency FBS720L screw blowers.
Result: The plant’s process is optimized and is consuming nearly 50% less energy per month. 800-981-6888; www.us.kaeser.com
Submersible solids-handling pump helps protect town
Problem: The County Home Lift Station operated by the town of Danville (Indiana) Wastewater Department sits downstream from a hospital, jail, and landfill. Clothing, needles, toothbrushes and other debris from these facilities repeatedly clogged the station’s three pumps, driving up costs and hindering productivity. The station required frequent emergency unclogging manually or with vacuum trucks, presenting biohazards for team members. Clogged pumps accentuated by large rain events put the jail, hospital, and town residents at risk.
Solution: The town chose a Pentair Hydromatic next-generation submersible pump, which uses a semi-open stainless steel impeller and self-cleaning cutter plate to eliminate tough clogs. The premium efficiency motor is oil-filled for lower running temperatures and has Class H insulation, increasing service life and saving energy. To combatting grease buildup and solids settling, the volute is mix-flush ready.
Result: At the first inspection, personnel noticed that the wet well was significantly cleaner with less trash and debris. “It does so much work for the other two pumps,” says Wayne Herring, wastewater operator. “We’re not clogging up.” Laborer Chris Tidd touted cost savings and improved work life: “We have 17 of these stations. If we have one of these in each station, the time freed up is drastic.” After a 90-day trial, the pump had passed over 17 million gallons of wastewater at 754 gpm and experienced no clogs. 763-545-1730; www.pentair.com
Pinch valve ever provides reliability and control in wastewater plant
Problem: The Miami-Dade County (Florida) Water & Sewer Department planned to upgrade its wastewater facilities to allow for some 20,000 new jobs over the next 10 years. The upgrade would also improve water and sewer system reliability and sustainability and increase the service capacity.
Solution: A massive DN1350 54-inch Flowrox electrically operated pinch valve from Valmet Flow Control, one of the world’s largest, was chosen to provide reliability and flow control for the wastewater treatment plant. The valve has two pinch devices that close the valve on the center line. This provides a flow regime concentrated in the center of the valve, reducing wear and velocity through the valve.
Result: The new technology will combat emerging contaminants such as PFAS. It will accurately control influent (up to 125 mgd) and provide reliability and control to one of Florida’s largest wastewater treatment plants. 410-636-2250 www.valmet.com
System helps utility exceed THM removal expectations
Problem: With 16 mgd capacity, the Newport (Rhode Island) Water System draws from nine surface reservoirs. When one aboveground tank experienced high trihalomethanes, the city sought remedies. While exploring an alternative to carbon filtration pressure vessels, the city required a performance guarantee of 50% average TTHM removal for the new solution.
Solution: The city chose a PAX TRS THM removal system from USG Water Solutions. The company installed a custom-designed, energy-optimized system of mixers, aerators and ventilators to convert water storage tanks into water treatment systems. The solution consists of a PWM400 mixer, two SA-75 surface aerators, a PPV-600 Powervent and an integrated control panel. The mixer at the tank bottom circulates water to the top where it contacts the air. The aerators blow air into the tank to freshen the air in the headspace while creating a splashing effect to help THMs escape. The high-efficiency Powervent then exhausts the THM-rich air.
Result: After several months, the system achieved an 81% TTHM removal. 855-526-4413; www.usgwater.com
Pumps cut maintenance downtime for dosing corrosive ferric chloride
Problem: Ferric chloride, used for coagulation in the water treatment process, resulted in maintenance downtime for Saur, a France-based provider of water management services at its water purification plant in the Orne basin of Caen. This heavy, aggressive chemical regularly caused technical problems by attacking components of the dosing units, such as pumps, valves, pulsation dampers, check valves, back pressure and safety valves, and flowmeters.
Solution: The diaphragm pumps were replaced with Qdos chemical metering and dosing pumps from Watson Marlow Fluid Technology Solutions in 2021. The pumps offer a high-performance alternative to diaphragm pumps: their ReNu pumphead can be quickly dismantled and replaced without tools and requires no maintenance or specialist training for operators. In addition, an integrated leak detection system reduces losses and avoids operator contact with corrosive chemicals like ferric chloride.
Result: “Watson-Marlow has provided us with an operating table showing that operating costs are lower. The extra cost of materials is paid off in three years,” says Gilles Garcia, head of Drinking Water Production for the Caennais Basin at Saur’s Orne plant. “Furthermore, we went from diaphragm pumps that consume 0.75 kWh to Qdos pumps that consume 0.20 kWh, so we’re reducing our energy consumption by three.” 800-282-8823; www.wmfts.com
