The Challenge
Two horizontal self-priming pumps had been pumping from two separate 9-foot deep sewage sumps. These pumps were supposed to send raw sewage collected from the chemical manufacturing facility to the nearby wastewater treatment facility, but they clogged excessively and led to inconvenient flooding on two separate occasions. Each time the flooding occurred, employees had to be moved out of the manufacturing facility into rented trailers placed off-site and a third-party company had to come clean and sanitize the flooded area. The clean-up was a lengthy process, and costly!
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Not wanting to risk a flood of raw sewage a third time, the chemical manufacturer’s maintenance manager contacted Swilley to discuss replacing the self-priming pumps. In discussing the problem with Swilley, it was clear that the new pumps to be selected for this sewage lift application needed to meet the following requirements:

• Non-Clog. It was critical to select non-clog pumps that could handle the solids and raw sewage that entered the sumps. The new pumps needed to reliably transport the raw sewage out of the sumps to the effluent treatment facility.
• Rated for Continuous Duty. The pumps in these sumps operated almost 24 hours a day, 7 days a week; so it was important to install non-clog pumps that could run reliably for extended periods of time.
• Durable and Reliable. The maintenance manager’s goal was to avoid flooding, so it was critical that a pump with proven reliability be installed in these sumps.

The Solution
 The chemical manufacturer had previously installed BJM Pumps in several drainage sumps throughout their facility. Having 6 corrosion-resistant stainless steel submersible shredder pumps (model SKX15CSS) already operating reliably in their chemical manufacturing facility, the maintenance manager was confident in the SKX Series pumps.
For these specific sewage lift sumps, Swilley recommended an SKX model, the SKX110CSS, for the following reasons:

• The SKX110CSS submersible shredder pump will not clog. Manufactured with non-clog, two-vane impellers designed for high volume and lift performance, the SKX has been proven to cut and pass solids up to 3.5 inches in size, while delivering high liquid volume at up to 845 gallons per minute. The SKX, which is specifically designed for industrial shredding applications, uses an engineered Tungsten Carbide Tip Fang™ impeller. This specially engineered impeller cuts against a spiral-shaped diffuser plate to continuously rip apart solids-laden sewage with 360-degree shredding action.
• The SKX110CSS is manufactured from corrosion-resistant stainless steel. All the internal components exposed to the raw sewage being pumped are made of 316 Stainless Steel; this includes all wear and wetted parts, such as impeller, wear-plate, seal chamber, and pump volute. The elastomers, such as O-rings, lip seals, and gaskets, are made of durable FKM. With a durable construction, this pump is rated for continuous duty and built to last.

There is no doubt that Hurricane Florence was one of the worst weather disasters to hit North and South Carolina. The hurricane hit the Wilmington area especially hard. Flooding closed all roads leading in and out of the city at one point. The numbers tell the story well:

• 02 inches of rain making it the worst rainfall event in Wilmington ever (2nd worst ever in the United States)
• 105,000 residents without power
• 1,215 people stayed in one of five shelters through the storm

UNDERSTANDING THE APPLICATIONS This new recycling facility is designed to receive large bales of compressed PET bottles—bales approximately 6 cubic feet in size. These bales are dismantled, and the bottles are sorted and shredded into much smaller plastic pieces prior to being sent through a series of processes. Because PET (polyethylene terephthalate) is semi-porous and typically absorbs food and beverage molecules, the shredded plastic must be finely chopped into “flakes” and thoroughly washed and dried. The cleaned, processed plastic is then bagged and distributed to other companies who use recycled plastics to manufacture consumer packaging, plastic banding, and a range of other goods.

The design engineers specifying the pumping systems worked with Derrick Heard at Tencarva, explaining that there would essentially be two sumps—a primary and a secondary pit—used for the rigorous cleaning process. During the initial grinding and cleaning, wash down water, plastic pieces, dirt, soap, scum, and residue would all be collected in the primary wash down sump. This material would then be pumped through clarifiers and screens to separate the plastic from the wash down wastewater. While the plastic would be sent through for drying, the wash down wastewater would be sent to the secondary pit. The pumps in the secondary sump would be responsible for reliably transporting the wash down wastewater to the on-site wastewater treatment plant. The wastewater would be treated on-site, with the facility technicians making sure all plastic and sludge had been removed prior to sending the wastewater downstream to the municipal sewer system.

PICKING OUT THE RIGHT PUMPSAfter speaking with the design engineers, it was clear to Heard that there were some key requirements that needed to be considered in order to select the right pumps for these specific sump applications:
The pumps needed to withstand high temperatures. The temperature of the wash down water was estimated to reach temperatures between 131 and 140 degrees Fahrenheit (55 and 60 degrees Celsius), which is too hot for standard submersible pump motors. Submersible pumps typically rely on the fluid being pumped to cool the motor; which is why most submersible pumps cannot withstand pumping liquids at temperatures higher than 104 degrees Fahrenheit. Temperatures higher than 104 degrees Fahrenheit (40 degrees Celsius) typically cause standard submersible motors to fail.

The pumps had to be corrosion-resistant. The wash down water would include cleaning chemicals that would cause the oatmeal-like slurry to be 2 percent caustic. For this reason, it was important to select a durable pump with the right metallurgy to minimize abrasion / corrosion.

The pumps must shred the plastic pieces. The plastic solids entering the primary sump needed to be shredded into even smaller pieces so they could be transported to the next stage of the process. This severe application required a shredder pump.

Heard immediately thought of BJM Pumps, explaining, “I knew BJM had a Fahrenheit Series—not just a submersible that could handle high temperatures, but one that could shred too. The combination is unique in the industry—and prior to BJM Pumps—there really wasn’t a high temperature option that could do all these things.”

Heard recommended the BJM Pumps’ SKG Fahrenheit Series Submersible Shredder Pumps to the design engineers. In his recommendation, he shared the key features of the SKG-F Submersible Shredder Pumps:
The SKG Fahrenheit® Series Submersible Shredder Pump is proven to reliably handle very hot liquids—up to 200 degrees Fahrenheit (93 degrees Celsius).

The SKG Fahrenheit® Series Submersible Shredder Pump is designed with patented RAD-AX® Dual Shredding Technology, which employs both radial and axial shredding. A rotating cutter bar with serrated edges traps and shreds solids against the sharp grooves of a radial cutting ring while multiple axial cutting bars shred any leftover material exiting the radial cutters.

All the shredding components of the SKGF Submersible Shredding Pump are manufactured in hardened 440C Stainless Steel (Rockwell hardness of 55C plus), which means this durable pump is constructed to resist wear and operate longer than most submersible shredder pumps currently available to the market.

​Two impeller trims are available for each SKGF model to expand hydraulic coverage, with large solids easily passing through impeller and volute. Controlled Shredding System Efficiency alleviates potentially high surge load to the motor.

The SKGF Submersible Shredder Pump relies on a high-torque, four-pole motor to ensure solidsladen wastewater can be moved efficiently. The motor is protected by an oil-lubricated double mechanical seal design, with separate lip seal.

Manufactured with a corrosion-resistant stainless-steel motor housing, the SKGF Submersible Shredder Pump has motor winding protection that includes NEMA Class R motor insulation – allowing motor temperatures to rise up to 428 degrees Fahrenheit (220 degrees Celsius) without damage. Automatic thermal switches embedded in the motor windings protect the motor if the temperature or amperage rise too high. When the motor cools, the automatic switches will reset and allow the pump to restart.

The design engineers reviewed Heard’s recommendation to put two SKG37CF Submersible Shredder Pumps into the primary wash down sump and two SKG15CF Submersible Shredder Pumps into the secondary wastewater sump. They also watched the video to see how the RAD-AX® Dual Shredding Technology is proven to obliterate solids. After a thorough review of the entire pumping system specs, the decision was made to purchase and install the BJM Pumps.

In February 2016, two 5-horsepower SKG37CF Submersible Shredder Pumps were installed in the primary sump, and two 2-horsepower SKG15CF Submersible Shredder Pumps were installed in the secondary sump. Heard was on-site in August 2016 when the pumps were started up, with the SKG37CF’s pumping 275 gallons per minute at 35 feet of head and the SKG15CF’s pumping 115 gallons per minute at 35 feet of head.

Since start-up, Heard has repeatedly visited the bottle recycling facility to check on these pumps. “Other than the one time we had to check the controls operation of the two sumps and clear the nasty slurry build-up off the floats, the BJM Pumps have been working great in the sumps,” states Heard. “They’re really reliable pumps.”

ABOUT THE AUTHORSteve Mosley is regional manager for BJM Pumps. BJM Pumps, headquartered in Old Saybrook, Connecticut, has been providing fluid handling solutions for industrial and municipal services since 1983. Over its thirty-year history, BJM Pumps has grown quickly by supplying world class pumps and accessories, priced competitively, through its global network of stocking distributors.

While the specifying engineers at the consulting design firm were reviewing the requirements of one 15-foot deep sump inside the wastewater treatment plant, they determined that the process required:
Image 1. Leachate from a landfill near a new wastewater facility may have affected the safety of the personnel and pumping equipment. (Images courtesy of BJM Pumps)

1. Pumps with explosion-proof motors—This indoor sump was classified as a potentially hazardous area because of the gases that could result from the combination of fluids entering it. Explosion-proof zones are defined in areas where flammable gas has the potential to be ignited by the arc of an electrical device.
2. Pumps that can handle acidic fluid—The sump would be collecting unscreened building wash-down water, membrane bioreactor (MBR) permeate, cooling tower blowdown and dewatering press filtrate. In addition to creating a potentially explosive atmosphere, this combination of wastewater could create an acidic solution with low pH levels, which can corrode standard cast iron submersible pumps.
3. Pumps capable of passing rigid solids about a half-inch in size and spherical in shape—The leachate entering the wastewater sump was estimated to contain up to 10,000 milligrams per liter (mg/L) of solid materials.
4. Pumps sized to produce 600 gallons per minute (gpm) at 78 feet of total dynamic head (TDH)—After the specs were fully defined, the consulting design firm chose to work with a company that supplies a range of rotating process equipment to industrial and municipal operations throughout the southeastern United States. The engineers reviewed the pump specs and recommended an explosion-proof pump.

Image 2. Leachate is liquid that drains from a landfill after it rains.The explosion-proof submersible shredder pumps were recommended because they are engineered with necessary features, such as:

• The pump has an explosion-proof motor approved for use in Class I, Division 1, Groups C & D hazardous locations. This approval certifies that the submersible pump motor is spark-free, has no source of sparking inside the motor that can cause ignition and, in the case where ignitable gases might enter the inside of the motor housing, the design of the pump motor has the capacity to extinguish the flame from that ignition before the flame can exit the vessel. The vessel can contain the pressure generated by an internal explosion, thereby keeping plant personnel safe.
• The pump is manufactured from corrosion-resistant stainless steel. The pump end components are made of 316 stainless steel, including all wear and wet parts: impeller, wear plate, seal chamber and pump volute. The elastomers, such as O-rings, lip seals and gaskets, are made of a chemically resistant flouroelastomer (FKM). The motor is treated with an epoxy coating that holds up in aggressive chemical environments. With the right metallurgy and durable construction, this submersible shredder pump would be ideal for pumping this particular process waste.
• The pump is engineered to shred solids and has been proven to cut and pass solids up to 3.5 inches in size. Specifically designed for industrial shredding applications, the pump uses an impeller to cut against a spiral-shaped diffuserplate and continuously rip apart solids with 360-degree shredding action.
• The pump has a three-seal motor protection. The motor is protected with an oil-lubricated double seal design where the double mechanical seals are comprised of a lower seal made of silicon carbide/silicon carbide and upper seal faces made of carbon/ceramic. An additional lip seal is installed above the impeller to help prevent abrasives from entering into the seal chamber. Seal leakage detectors are installed in the seal chamber and offers early warning should water enter the chamber. The pump has an air-filled motor with winding protection and National Electrical Manufacturers Association (NEMA) Class F motor insulation, allowing the motor temperature to rise to 221 F before an automatic switch turns the pump motor off if the temperature and/or amp draw raises too high. When the motor cools, the switch is designed to automatically reset and the pump will once again begin operating. Since the fluid temperatures were estimated to range between 50 F and 90 F, this would be a nonissue for the pumps.

With the assurances provided by the consulting firm, the owners of the new wastewater treatment facility approved the purchase of the submersible shredder pumps.
In April 2017, two explosion-proof submersible shredder pumps were installed in the indoor sump. The pump company provided the guide rail system that enabled the installation team to easily install both pumps, which are run off level control.
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The submersible shredder pumps are set up to run in an alternating lead-lag configuration, to prolong pump life and to accommodate possible higher inflows into the sump.
Managing safety is a necessity for many industries. The implementation of explosion-proof zones on the job site has created a need for explosion-proof pumping equipment and consulting engineers who must know what proven technology is available to the market.

ABOUT THE AUTHORJonathan Herlong is a sales engineer at Tencarva Machinery. For more information, visit tencarva.com. Steve Mosley is a regional manager at BJM Pumps.

How one submersible pump helps provide clean energy. by Keith Grgurich October 8, 2018

Infrastructure has been a hot topic for years now, particularly in utility circles. In the wider public, Americans are aware of infrastructure because so many of us depend on having navigable roads and bridges to get from one place to another, and these days they are overcrowded and often in need of repair.
Other people may have an appreciation of the importance of infrastructure if they work in an area where a broken water main has flooded homes and businesses or disrupted service. Typically, we think about infrastructure only when it is not working properly, and usually that is because it has caused an unexpected inconvenience.
Utilities, whether public or private, and the infrastructure networks they maintain serve as the (often unseen) bones and skeleton of our cities and towns. Not only do utilities provide necessary services to residential areas, but they also service retail centers, manufacturing facilities, other utilities (water treatment facilities are some of the largest users of electricity) and business districts.

Image 1. The convention center in a Midwest city underwent a renovation after a sump used to collect condensate from steam heating caused issues. (Images courtesy of BJM Pumps)That final category often includes facilities such as convention centers, ballparks and theaters.

Many large facilities and high-rise buildings found in a typical downtown make use of a utility that is not often thought of—steam. Most people at some time have walked through a stadium, for example, and looked up to see the word “STEAM” stenciled on a pipe overhead. Steam is an efficient source of heat and energy that is commonly used in manufacturing as well as business districts with concentrations of high-rise buildings and other facilities that accommodate large numbers of people.

Steam is considered “clean” energy since it is nonflammable, nontoxic and chemically inactive with several process fluids.
But there is still waste—more or less of it depending on how the steam is generated and used.
Without the proper equipment to address it, this waste can cause significant challenges for facilities that have to deal with it.

The FacilityIn the past decade, a city in the American Midwest initiated a project to upgrade and expand its convention center. Today, that facility is one of the largest convention centers in the country.
The distinction comes with significant demands on the various utilities that service the facility. Convention centers and other venues that host tens of thousands of people typically go from being virtually empty to the size of a small city in a matter of hours. One of the consequences of this quick transition is that the demands put on the infrastructure supporting the facility are nearly instantaneous and great.

In the winter, it is cold in the Midwest, and if the convention center is in use, its vast halls and meeting rooms need to be heated. In this particular facility, heat generation is accomplished with steam.
The ChallengeDepending on steam’s source and unique characteristics, the resulting condensate can be corrosive and hot. Accordingly, this expanded convention center has a number of sumps to collect condensate from the steam heating.

One sump in particular was creating constant problems for maintenance crews because the vertical-style sump pumps were being damaged due to the hot, corrosive condensate.

Image 2. A high temperature submersible pump in 316 stainless steel was chosen for this application since it can handle liquids up to 200 F continuously.“The pumps had to be replaced every year,” said Jeff Cook of Cook Fluid Products. “The hot, corrosive condensate would prematurely wear the vertical-style sump pumps. In this application, the combination of the heat and corrosive fluid damaged the pump’s bushings and shafts.”
The steam in this location is generated by the local gas utility at a central plant and then is piped out to customers. In this application, the steam is untreated and as a result contains high levels of carbonic acid. The resulting condensate is highly aggressive and “would corrode parts on the vertical sump-style pumps,” Cook said. “A lot of other places in the city that use this steam use stainless steel equipment in order to get any longevity out of it.”
Although the convention center sends condensate to waste rather than returning it, the condensate still has to be collected. Just maintaining that location was a challenge.

“The pit that the pumps are in has a Rhino liner in it because the pit itself was being destroyed by the condensate,” explained one employee.

The SolutionThe apparent answer to this ongoing problem was to find and install a stainless steel pump that would handle the highly corrosive environment and extremely high temperatures. Having reliable equipment saves time and money because production time is not wasted identifying a problem and bringing in new equipment to solve it.
“It’s a very tough application,” Cook said. Cook recommended a manufacturer that has a line of high temperature stainless steel submersible pumps for this site.

The appropriate pump line is designed to handle liquids up to 200 F continuously. Standard sump pumps are normally rated to handle 104 F continuously. The high temperature submersible pump is available in all 316 stainless steel constructions for hot corrosive applications. The higher temperature rating and stainless steel construction made this pump the correct choice for this application.
The pump manufacturer also provides standard peripheral equipment to support its pumps.
All pumps from this line come with a National Electrical Manufacturers Association (NEMA) 4X control box including start components. The control box contains some additional features for high temperature pumps that ensure the equipment maintains its reliability even in challenging environments.
“They make heavy-duty control panels,” Cook said.

Especially useful for this application is a device located in the control panel that initiates an alarm in the event there is a breach in the double-mechanical seal chamber.
“I always suggest using the seal minders,” Cook said. A moisture sensor probe is installed in the oil-filled seal chamber between the inboard and outboard mechanical seals. If the outboard seal is breached and a conductive fluid enters the seal chamber, the moisture sensing probe completes an electrical circuit that illuminates an alarm light on the control panel. This feature potentially saves time and money by alerting the user that a seal needs to be changed before moisture gets into the pump motor.
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“If the inboard seal is breached and water gets in the motor, the pump will normally have to be replaced,” Cook said. “So it makes sense to use the control panel with the extra security to make sure the pumps can be serviced if necessary before water gets in the motor. Replacing a seal is inexpensive.”
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The OutcomeIt has been more than a year since the pumps were installed at the convention center and none of the previous problems have resurfaced.
Ultimately, finding a solution that prevents pumps from having to be repaired or replaced on a regular basis has a positive effect on the facility’s bottom line. In addition, maintenance crews do not have to spend unscheduled time and effort repairing or replacing equipment at the expense of their regular duties.

BJM Pumps has expanded its JX Series line of submersible pumps, to include the new JX150CSS & JX220CSS. The newest models are designed for applications where caustic or acidic fluids are present, such as those in food, chemical or pharmaceutical processing.
  Top features include:

• All metal parts exposed to pumped liquids are constructed of 316 Stainless Steel.
• Double Mechanical Seal Design, with separate lip seal to protect the motor.
• All elastomers, including mechanical seals are FKM.
• (NEMA) Class H Motor Insulation 302¬∞F (150¬∞C).
• Motor Overload Protection: Thermal Switches embedded in the motor windings protect the motor if the temperature or amperage rises to high.
• Seal Minder motor protection is standard.
• Heavy Duty power cable (50′) and Seal Minder¬Æ cable (50′) –

BJM Pumps announces the release of the new XP-SKG explosion proof electric submersible pumps.The XP-SKG pumps are specifically designed for tough conditions where explosion-proof, FM C/US approved (Class I, Division 1, Group C & D) are needed. The XP-SKG features patented RAD-AX¬Æ Dual Shredding Technology, designed to obliterate tensile fabrics and other difficult solids in municipal and industrial wastewater applications.
The XP-SKG features robust construction and unmatched design, making it able to outperform and outlast standard wastewater predecessors in harsh environments. 
Top features include:

• RAD-AX¬Æ Dual Shredding Technology (patented) featuring radial and axial shredding elements.

• All shredding elements constructed of hardened 440C Stainless Steel with a Rockwell hardness of 55C plus.

• Shredding System efficiency to alleviate potentially high surge load to the motor.

• Efficient, high solids passage impeller and volute design, coupled to a high torque 4-pole motor. (2, 3, & 5 HP)

• Trimmed Impellers – BJM Pumps¬Æ offers two impeller trims for each of our SKG models to expand hydraulic coverage.

• Oil-lubricated Double Mechanical Seals and separate lip seal design to protect motor.

• Heavy Duty SOOW power and sensor cable – construction provides motor lead and sensor lead cable protection.

The hardened impeller and suction cover materials provide maximum wear resistance for long service life. (NEMA) Class F motor insulation and 1.15 service factor allow for higher service loading. Additional motor protection through Seal Minder¬Æ – seal leak detection system and motor thermal sensor switches embedded in motor windings. The automatic motor thermal switch turns the pump motor off if the temperature and/or amp draw rises too high. When the motor cools the switch will automatically reset and the pump will turn back on. 
GPM to 410. Heads to 42′.
Typical applications for the XP-SKG pumps include those at food processing plants, in digested sludge wastewater, at shopping malls, prisons, tank farm moats, airports, trailer parks, distilleries, campgrounds, battery recycling, bottling plants and many others.