Clogging Pump Station Needs Innovative Approach

icon-75x75-municipalCornell and partners tested various Cornell cutter variations to help alleviate ragging; new hybrid cutter—auger worked best.

117TH_STREET_CLOGGINGA Southwest Washington water district started a waste water management system to address the needs of 77,500 residents. The system has a pump station with 18.4 mgd capacity at 200’ TDH.

Shortly after being placed in service in December of 2008, the station experienced daily ragging that caused capacity to degrade from approximately 3,750 GPM to around 2,900 GPM. That flow decrease shaved more than 1.2 million gallons of operating capacity per day. The system was paying the same energy cost to pump less liquid though, effectively increasing costs. Material was also accumulating in the wet well.

The system operator tried fixes such as operating at different speeds and different operating levels. They changed the pump order, and institute a self-cleaning cycle. None of the fixes stopped the ragging, though. The station was taken offline in April 2009, and operated seasonally. In that capacity it had to be deragged twice a day, seven days a week; costing four hours of staff time per day.

Cornell won the 2012 Pumps & Systems Innovative Product of the Year for our cutter pump technology. The original design of the cutter was placed in the system in 2012. While the cutter reduced some of the issues and increased the flow rate, the eye of the impeller was still getting clogged more frequently than the system operator wanted.

Cornell got to work creating more than half a dozen prototypes designs for new cutters to deal with the plugging of the impeller eye; there was not enough vane geometry to guide the flow of solids into the impeller passageway. Ultimately, the solution was using the stationary cutter from the original cutter system, and adding a hybrid cutter—auger that extended impeller vanes all the way to the center, while using the auger as cutter of the ragging material.

The new cutter—auger design reduced capacity somewhat, but kept a consistent flow rate throughout the day. Ragging events were reduced more than ninety percent. The municipal water district is looking at retrofit other pump stations, in order to reduce ragging events.

Cornell’s Hydraulic Fracturing Water Transfer Pumps bring the Power

MX_6822_ALBERTA_OIL_SHALE (1)icon-75x75-oilgasIn Alberta Oil Shale, Cornell bests competitors’ pumps with the MX6822

An Alberta oil field service company providing water transfer services, mostly supplying frac water, had purchase some 6” pumps from a Cornell competitor. After the oil field company put them in service, they realized they did not produce the volume and pressure required to do the job.

The customer approached a Canadian Cornell distributor for a better option. Three MX 6822 engine mount pumps were sold and then mounted on diesel engines with trailers. The customer now is completely satisfied and cannot believe how much more volume and pressure he can get with the Cornell over the competitors pump. Operating conditions are 3000 GPM at 400’ TDH.

Cornell’s MX series, introduced in 2011, are high-head pumps, with three or four vane enclosed impeller designs. MX pumps handle up to 2” solids with excellent efficiencies; up to 75 percent. The MX series features high operating pressures, is useful for high flow requirements, and come with Cornell’s renowned dependable and high quality construction. Heads up to 800’, flows of 8,00 GPM, and operating pressures of 300 PSI are attainable with the Cornell MX series.

Peruvian Wastewater Treatment by Way of Montana

6NNT_MONTANA (1)icon-75x75-municipal6NNT dredge pumps help remove sludge lagoon biosolids in Peru

For over 45 years a Cornell customer based in Montana has helped their customers meet their most difficult pump and dredging challenges. This Cornell customer manufactures unique, high quality floating dredges for industrial and municipal applications.

In 2011, they had a request from a municipal wastewater treatment plant in Peru, for two dredges mounted with Cornell 6NNT-30HP-1800rpm submersible pumps to dredge biosolids and residuals from a municipal wastewater treatment plant. The pumps operating conditions are 1500 GPM @ 50’ TDH each.

The company mounted Cornell 6NNT pumps on floating dredges. They attached cutterheads to help break up the sludge that has settled on the lagoon floor. The floating lagoon dredge pumps are portable, fully automated, unmanned remote controlled units.

The dredges help remove settled wastes and other by-products that no longer may be scattered over the countryside, but, instead, must be contained in settling ponds or lagoons, built to prevent wastes from leaching into the water-table.

These pumps have been in operation since 2012 with no issues.

Keeping Hawaii Beautiful and Economically Viable

photoicon-75x75-municipalSix Cornell 16NHG28 pumps help protect vital commercial and tourist bay from effluent

Mamala Bay, named after a legendary Hawaiian chieftess renowned for her surfing ability, straddles some of the most expensive and desirable real estate on the island of Oahu. It is also the only harbor in the United States that combines both commercial and tourist functions in one spot. Tens of millions of tons of cargo are off loaded yearly at the working port, the adjoining Aloha Tower Marketplace is a great tourist attraction, and the water from the shallows of Honolulu Harbor flow directly into the bay past coral reefs.

Mamala Bay had a problem with raw sewage spills. These discharges threaten to disrupt the commercial, tourist, and environmental activities of the bay. The losses could potentially reach hundreds of millions of dollars.

Cornell was called in to engineer a bypass system while the aging and overtaxed current sewage treatment system was upgraded to chemically enhanced primary treatment plants, with primary outfall discharges changed from chlorine to ultraviolet disinfection.

To handle all the sewage while the change was made, the sewer district operated six Cornell 16NHG28 pumps on trailers. The entirety of the effluent of an area with more than 1.5 million residents and tourists was passed through the six pumps flawlessly.

The 16NHG28’s pumps were located around the treatment facility and moved the wastewater into the old treatment plant for more than two years as the new plant was and piping was built.


icon-75x75-municipalTwo Cornell 14NHG 28RPEMTB pumps help alleviate failure of previously installed pumps; working flawlessly since 2011.

OLYMPUS DIGITAL CAMERAA municipality in the United Arab Emirates had installed twin 700 HP submersible sewage pumping equipment in 2005. Repetitive failures of these pumps occurred due to system mismatches and severe vibrations. Lacking adequate backup and given the systems problems, the client with was concerned. Failures included seal leaks and on some occasions, sewage seeping into the motor windings and burning out the motor, with some shaft shearing as well.

OLYMPUS DIGITAL CAMERAClient’s expenses on emergency maintenance and repairs reached towards than 200 percent of their installation investment. Additionally, the pump station was located in densely populated area of the city, hence any shut down would be an awful situation

CENTEX FP LLC, Cornell’s distributor and technical supports office in Middle East & North Africa (MENA) worked with the municipality to find a solution that would allow them to use a Cornell pump as a complete back up, which would keep the system operational with minimal modifications in piping. Centex conducted a complete site study, including system resistance, average / peak flow situation, and piping design. After the thorough review, they were able to offer suitable pumps that would not only handle this station at peak load but also another master station which has similar issues.

Cornell’s Redi-prime system® was seen as real asset with ability to run dry and be able to lift the sewage from nearly 23 feet (seven meters) deep. In February of 2011, two Cornell 14NGH28 Redi-Prime® pumps were installed, and have been working well ever since. The pumps each operate on a 630 HP Cat engine, each with 9200 GPM (580lps) at 206 feet of head, for a total flow of 18,400 GPM (1160lps.) It just took two of Cornell’s 14” pump to accomplish that flow, while a competing system designed required 6 units of 10” pumps to match. Understandably, the Centex & Cornell team won the contract on merit, offering the best performance and system solution for the client.

In an appraisal letter the client described their experience as:
“We are extremely satisfied with these pumps completely designed, manufactured, tested and commissioned by Centex-Cornell. In fact, the pumps by far exceed our expectations, not only in terms of product quality, pumping capacity and performances, but also in terms of reliability, robustness, solids handling ability (the pumps never clog), suction lift ability (7.56 m), fuel consumption (very low) and maintenance requirements (just basic routine checks).

Furthermore, we are tremendously grateful to Centex-Cornell for the professional services they offered us well ahead of the decision to select their product.”

Cornell 8H-VC18 Pumps Form a ‘Green Dragon’

icon-75x75-municipalMuscle, Ingenuity, and Determination need to move Cornell Pumps 250 Miles into the Jungle to Supply Fresh Drinking Water

Two vertical mount 8H-VC18 units were installed in the Colombian jungle on the river Caucasia, about 400 kilometers (248 miles) South of coast. Because of some interesting features, the installation earned the nickname the Green Dragon.

8H-VC18 Columbia (1)The pumps were designed in the vertical position in order to elevate the motors to avoid damage from flooding – a regular occurrence during the rainy season. The pumps replaced a locally manufactured brand, IHM. The pumps were put in series, to overcome a relatively high pressure requirement due to a 1.5 kilometer (~1 mile) distance of piping to a local village. The pumped river water is being used to supply the village with fresh treated water for personal consumption. Due to the Rain-a-flo blue paint color (which actually looks green) and the exotic discharge and suction piping design, the locals named the pump installation the Green Dragon.

8H-VC18 Columbia (14)The logistics required to get the equipment to the job site was interesting in itself. The crew employed traditional banana boats to transport pumps, motors, pipes, etc., across the river to the pump house. Once the equipment arrived, a system of wooden rails and rollers were used to move the pumps and motors along the ground and in some cases, sloped gradients. Ropes and block and tackle apparatus were used to do a lot of the heavy lifting, as no powered cranes were available.

8H-VC18 Columbia (15)Pump house modification was also required, as the crew removed a large portion of the roof to accommodate the vertical installation and the discharge piping—the snoot of the Green Dragon. It was an incredible feat of local ingenuity to make this a successful installation; relying solely on manual labor, determination, and brute strength.

The pumps have been successfully in operation since 2010, supplying clean drinking water to the village.

European Waste Water Plants Uses Cornell Pumps to Reduces Foam, Help Sludge Settle

icon-75x75-municipalTwo major waste water treatment plants in Brussels faced issues with sludge circulation in the decanting basins; use of the previously installed pumps was creating too much foam, leading to sludge particles floating near and on top of the water’s surface. Because the sludge was not settling down into the basins as expected, the extraction process was not as effective as designed, and the pumps were using more energy than anticipated to operate.

18NHFL RP F24K - Cornell Pump Company ImageThe plants manager wanted a change to efficiency; that desire led to a change in extraction strategy. To alleviate the problem of the excessive foam, it was decided to pump sludge from lower tanks to higher tanks with Cornell Self-Priming pumps. These innovative Cornell pumps helped remove the excess air from the sludge before it was pumped into the upper tanks and comes into contact with the surface mixers.

Cornell’s self-priming pumps aided in the removal of air bubbles that were trapped in the water. At certain times observers could hear the vacuum pumps extracting the air that had already been separated from the water by turbulence. Under those conditions, pumps without self-priming capabilities would lose their prime because of the excess air. In the previous pumps that had been an issue; an issue that was solved beautifully by using Cornell self-priming pumps.

04---18NHFL-RP-F24K-Brussels-SouthThe installed Cornell pumps have two functions at the plant: initial priming at start-up and extracting the excess air during the pumping process. These pumps are driven by 90kW electric motors and are controlled by variable frequency drives that operate between 400 RPM and 600 RPM at the pump shaft. The maximum hydraulic efficiency of the pumps is 87.3%!

Six Cornell 18NHFL pumps have been working effectively at the Brussels plants since February 2011.

Cornell Efficiency = Sweet Success

4HH-F16_2008_0424May10106icon-75x75-agricultureWhen a large Guatemalan sugar cane producer was looking to purchase numerous diesel driven pumps, Cornell proved that efficiency does matter.

A US-based engine packager was asked to provide a quote on ten (10) diesel pump packages capable of hitting a design point of 800 GPM at 280’ TDH. Cornell’s best selection was a 4HH-F16 capable of hitting the design condition at 1920 RPM with an efficiency of 84%. A local company was offering a competitor capable of hitting the design condition at 1800 RPM but with an efficiency of only 68%.

Cornell met with the end user in Guatemala to debunk their misconception that a diesel engine burns less diesel fuel and lasts longer if runs at 1800 RPM. Equipped with pump curves on both pumps, an engine performance curve on the Deere engine, and a fuel consumption comparison chart, Cornell was able to inform the customer.

Just as pumps have various RPM performance curves which show flow and head at a given RPM; diesel engines also have performance curves which show Hp, torque and fuel consumption at a given RPM. There are a lot of similarities to the curves. The main similarity is that both the engine and pump have gradually sloping curves. In terms of the engine it usually means that the best fuel consumption is not a defined point (RPM), but rather best fuel consumption covers a range of RPM’s. With the engine performance curve, we able to show the end user that max fuel consumption was almost the same in terms of pounds of fuel per Hp per hour at 1800 RPM as it was at 1920 RPM.

The difference in fuel consumption was actually found in the pump performance. The end user had contracted fuel for the upcoming season at $4.50 per gallon; based on past experience, they anticipated 1900 hours of run time for the season per pump. After calculating Hp required for each pump, fuel consumption, fuel price and estimated seasonal usage, Cornell saved the end user around $2,800.00 per pump in fuel savings per season. That equates to over $28,200 per year savings for the (10) pumps.


Cornell 4HH-F16 Competitor
HP Required 77 83
Operating RPM 1920 1800
Engine Deere 4045TF250 Deere 4045TF250
Fuel Consumption (GPH) 3.85 4.18
Fuel Cost (US Dollars / Gallon) $4.50 (contracted rate) $4.50 (contracted rate)
Hourly Cost of Operation $17.33 $18.81
Hours of Operation per Year 1900 1900
Yearly Cost of Operation $32,918 $35,739


Cornell User Wins Profitability Award

Cornell 3WH Helps Georgia Farmer’s Efficiency


“I’ve been farming since 1983, and last year was the most perfect year for weather I’ve seen, says Tim McMillan, who along with his brother Steve owns and operates Southern Grace Farms in south Georgia’s Berrien County.

icon-75x75-agriculture“Efficient By Design” is more than just a slogan at Cornell. It is a standard to which we hold ourselves. Cornell is the most efficient pump line on the market. With production costs increasing, cultivatable land decreasing, and world populations increasing; the US farmer has to produce more with less to stay successful.

Our high efficient pump ends help farmers reduce power consumption and put more profits to the bottom line. Seventh generation farmers Tim and Steve McMillan were awarded the Lower Southeast Farm Press Peanut Profitability Award for 2013.

The Peanut Profitability Award is based on overall efficiency in producing a crop. This involves keeping input and overhead costs as low as possible. The McMillans produce cotton, peanuts, and corn as traditional row crops. They also operate two “you-pick” locations offering strawberries, blackberries, nectarines, and peaches.

The McMillans yielded an impressive 5,991 pounds of peanuts per acre in 2012 from their irrigated crop. Approximately 40% percent of his crop is irrigated under center pivot, while 20% is irrigated with cable tow machines. The McMillan’s purchased their first Cornell pump (3WH) from Cornell’s Nashville dealer in 2011. The 3WH has head up to 25’ and flow up to 760 GPM, boasts an 81% efficiency, and is part of our extensive line of agricultural pumps.

Congratulations to the McMillans and Southern Grace Farms.

New 8NHG19 Pump Hits Sweet Spot for Flow and Head

icon-75x75-oilgasNew Pump features 7,000 GPM, 625’ of head, and 82 Percent Efficiency!

As oil companies push to establish more wells for increased US production, the demand moves toward more flows and higher pressure to maintain adequate water supply at multiple hydraulic fracturing sites. Often companies are limited by pipe size, since they have lay the pipe out on top of the ground at the start of the job, and then take it up after the job is complete. As new pipe and hose hit the market carrying higher pressure ratings, companies continue to try to push more water through the same size pipe.

Earlier this year one of our Texas based OEM’s was approached with an application which required 4,500+ GPM at over 500’ TDH. This design condition hit right in between two our larger pumps that we regularly sell into the water transfer/oil field market. Our 6822MX can easily hit the head, but cannot quite hit the max flow. Our 8NHTH would easily hit the max flow but would fall well short on head. The only pump that we had capable of doing the job was our 81026MX pump which released late last year. The HP required to drive this pump coupled with its sheer size made this pump impractical for this particular application.

Cornell’s Solution: After an extensive R&D process, Cornell now has a new pump model that exceeds the customer’s expectations. The 8NHG19 is a high flow, high head, and high efficiency pump.