News from Schwing Bioset

Schwing Bioset, Inc. is Exhibiting at WEFTEC 2016


Schwing Bioset, Inc. is excited to be exhibiting at the 2016 WEFTEC Event in New Orleans on September 24 - 28.  

Please be sure to stop by our booth (#1828) while you're on the exhibit floor. We will be displaying our 1102 model screw press, which is one of the largest screw presses we manufacture, as well as our newest piston pump, the Smartec Sludge Pump System.   

The SBI team members attending the show include Executives, Managers, and Regional Sales Managers. If you'd like to meet with one of our team members, please email us and we'll put you in touch with the appropriate person.

Visit the conference website to view the event details and exhibition map: Here is the Schwing Bioset listing for the show.

For more than 30 years, Schwing Bioset, Inc. has been helping wastewater treatment plants, mines, and power generation customers by engineering solids handling solutions. Schwing Bioset’s custom-engineered solutions can be found in hundreds of wastewater treatments plants in North America, as well as mines, and tunnels around the world.

Our products include, among others, sludge, industrial, and tunnel piston pumps, screw presses, nutrient removal and management, sliding frame and push floor silos, fluid bed drying products, Bioset process for Class AA Biosolids, container wagons, and soil conditioners. We also offers spare parts and equipment maintenance services and training. 

Read about our Nutrient Removal and Struvite Harvesting, Dewatering Equipment, Smartec Pumps, Bioset Process and Class 'A' Biosolids, and other products hereand then stop by booth 1828 to learn more!

We hope to see you at WEFTEC 2016!

Smartec Sludge Pump          Screw_Press_NEW.jpg


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Tags: Events, WEFTEC, Expos

Southerly Sets The Standard with Sludge Disposal Efforts


Schwing Bioset Application Report 14, Columbus, Ohio

Written by Larry Trojak, Trojak Communications

Version also published in WE&T Magazine (click to view)


Pumps and sliding frames allow options for effective disposal of cake from Columbus, Ohio, operation.

Wastewater treatment plants can distinguish themselves in any number of ways: by the volumes they can handle, by the number of industry awards they have earned, by the manner in which they handle an interruption in “business-as-usual”, and so on. They can also do so by demonstrating a creative, effective and successful effort to use or dispose of the biosolids they generate. Given those criteria alone, the Southerly Wastewater Treatment Plant could likely be seen as one of the premier WWTPs in operation today. Just coming off a five-year, $350 million expansion which nearly tripled its peak capacity from 114 mgd to about 330 mgd (built-in contingencies for further expansion can take the plant as high as 550 mgd), the plant services the majority of the greater Columbus area. State-of-the-art in every regard, Southerly is poised to build upon an already impressive reputation that has won them numerous National Association of Clean Water Agencies (NACWA) awards for plant and employee performance.


But it is also its innovative sludge disposal program that separates Southerly from super-plant wannabes. Using a quartet of heavy-duty pumps and a number of sliding frame components (all from Schwing Bioset, Inc. [SBI] Somerset, WI) cake can either be routed directly for incineration or sent to a pair of storage silos. Once in the silos, the material is readily available for truck-loading and transport, either to an already-successful composting operation run by the department or directly to the landfill.  Options, it seems, are the hallmark of this successful operation. 

Change They Can Use

Built in 1967, the Southerly WWTP is one of two plants serving the Columbus metropolitan area (the other being the nearby Jackson Pike WWTP). The current plant expansion which so dramatically increased overall capacity, also increased volumes in the solids handling area. New centrifuges, installed a number of years in advance of that expansion, handle that increase nicely, according to Jeff Hall, Assistant Plant Manager.

“That upgrade was implemented both to replace aging equipment, as in the case of the centrifuges, and to add functionality to other areas like the transportation of solids,” he says. In the past, primary solids were gravity thickened while older centrifuges thickened the waste activated sludge (WAS). The new units now thicken both the primary solids and the WAS. This new approach boosts the solids content of the resulting dewatered cake to about 20-25%, a nice improvement over the 17-21% solids content with the older system.”

Additional changes brought about in that initial upgrade included installation of new cake pumps, a pair of storage silos, and sliding frames at two points in the solids handling process. 


The Route To Disposal

Getting cake to the point where disposal options are available is a function of Southerly’s pumps and silos. As material exits the centrifuges, it is routed to any of four Schwing KSP 45V(HD)L-SFMS pumps which direct it to the appropriate area. Where that is, varies greatly according to need.

“Even though incineration is the most efficient method of disposal, we still try to keep the compost operation fed with as much as it needs, since that is the better use of the product,” says Carmon “Skip” Allen, Solids Supervisor 2. “Obviously that can vary from day to day. The balance of the material—we can do anywhere from 5.5 tons up to 9 tons an hour—is then sent for incineration. But we know at all times what is going to the silos for storage and what’s getting burned.”

The sludge pumps at Southerly are designed to generate a force sufficient to move cake the long distances needed for either incineration or storage. He says it is easily 300 feet to the multi-hearth incinerators (which have operating temps of 1400°F), and about 400 feet to the storage silos. Equipped with Schwing Bioset’s Sludge Flow Measuring System, the pumps are able to measure to within +/-5% the amount of sludge that is pumped to the incinerator. This simplifies their USEPA reporting requirements for their incinerator operations.

“Material headed to the silos, however, has an additional challenge to overcome,” says Allen. “Once there, the cake has to go straight up another 100 feet to enter the top of the structures, so the force needed to do that is really pretty impressive. I don’t think any regular equipment would be up to a task like that; these are definitely the right pumps for the job.”

Giving it the Slip

Despite maximum operating pressures of 1,100 psi for each pump, those extended distances at Southerly prompted Schwing Bioset to make accommodations to help move the sludge along. To do so, they added a “slip ring,” or pipeline lubrication system. Schwing Bioset’s unique design includes a 360 degree annular groove that evenly injects a thin film of water around the entire annulus of the pipe that separates viscous and sticky materials from the inner wall of the pipeline. The end result is a reduction in friction loss in the pipeline, and lower—in some cases better than 50% less—pipeline operating pressures.

Additional benefits include a savings in energy by reducing the demand on each pump and hydraulic unit, and, because of the reduction in pipeline friction, an increase in wear part life. While other systems try to address the friction issue through the use of as many as four drilled ports which inject more fluid, this offsets a percentage of the gains made by the centrifuges. Still other designs mix polymer with the water to help reduce pressure which, while effective, adds both up-front and perpetual costs to the operation.

Tom Thomas, Maintenance Supervisor 2 at Southerly, says the reduction in friction has also shown benefits in wear part life for the pumps—a fact that is borne out in similar results at Jackson Pike. “We run these pumps round the clock and, even with that 24/7 operation, parts such as the pumping rams, poppet valve discs and seats are getting six months of wear. That’s about 4,000 hours of wear part life, which is outstanding given what they’re being asked to pump.”

Silo Efficiency

As mentioned, the SBI sliding frame silos offer a storage option for cake headed either to the landfill for disposal or to the compost site. Prior to their installation, Southerly relied upon a smaller holding vessel known as “the pit,” a belt-fed, hopper-equipped component that used a series of screws to feed a truck sitting under the discharge chute. City officials say the new silos are larger (providing about 75% more capacity) as well as far more efficient, thereby reducing truck loading times from 45 minutes with “the pit,” down to only five minutes. This was an important criterion when selecting equipment.

Because the City pays a contractor to haul the biosolids, reducing loading times lowers overall hauling costs—the trucks now spend more time hauling and less time waiting to be loaded. The net result is more trucks loaded per day (and a lower cost to do so.) In addition, because of that added storage capability, the composting operation now has the option of drawing material solely from Jackson Pike, if necessary. "Anytime you can reuse something rather than just burying it or burning it, you are making a positive impact," says Assistant Plant Manager Jeff Hall.

“Today, we are reusing about one-third of the solids we handle through the composting operation,” says Hall. “That’s obviously good from an economic standpoint, since we are generating revenue from a product that was once simply discarded. However, it is also a plus from an environmental perspective."

The concept of the sliding frame silo is simple, yet very effective. Hydraulic cylinders move an elliptical frame across the silo floor. The frame’s action not only breaks any bridging that can occur over the extraction screw, it also pushes and pulls material towards the silo extraction screws for discharge into trucks.

Allen says the sliding frame silos were a nice addition to the operation. “Each silo holds better than 1,500 tons of cake, so even if one of the incinerators went down and there was an interruption in the trucking operation, we’d still have a nice short-term storage option while things get back up again. It’s really all about flexibility and these silos afford us that.”

Due to the sheer size of the silos, they are each equipped with three extraction screw conveyors at the bottom which allows the trailers to be evenly loaded without having to be jockeyed back and forth.

The silos also include an odor and splash control shroud that pulls fumes directly off the trailer, thereby minimizing the need for odor control in the truck loading building. In addition, it helps reduce the chance of material splatter during load-out, and confines any such instances to the area immediately adjacent to the trailer, which makes periodic cleanup of the area much easier.

Allen adds that they also use SBI sliding frames on hoppers in advance of the pumps which feed the incinerator. Doing so provides a wide spot in the process line enabling them to maintain steady incinerator operations for several hours in the event of any upset condition with the centrifuges.

Sibling Growth

Southerly WWTP’s growth is being mirrored in the expansion of its sister plant, Jackson Pike WWTP, located a mere seven miles from Southerly’s facility. That plant also installed SBI equipment for similar end uses, but because its capacities are less, scaled down the size of that equipment. So today, Jackson Pike uses a quartet of KSP 25 V(HD)L pumps, rather than the 45s in use at Southerly and powers them with a 100hp power pack compared to its 150hp counterpart. The silos, though smaller in height, are of the same design and offer the same performance benefits as Southerly’s. Once the expansion at Jackson Pike is complete, the two plants will effectively meet all of Columbus’s wastewater treatment needs for decades to come. For Skip Allen, seeing construction at Southerly come to an end after nearly six years is a welcome relief.

“We are all really happy about the changes that have taken place here; there’s no doubt about that. But it feels like we will now finally be able to get back into the treatment plant business. With construction done, we have a big headache behind us, we have a great operation in place, and we’re doing good things for the residents of Columbus. That’s not a bad place to be.”



To download the entire #14 application report for Columbus, Ohio, click here.

To learn more about Schwing Bioset, our products and engineering, or this project specifically, please call 715-247-3433, email, view our website, or find us on social media.


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Tags: Sliding Frame Silos, Municipal Pumps, Truck Loading, Wastewater Treatment, Biosolids

Material Classification in Drying Operations


Written by Joe Scholl, July 18, 2016

The word “classify” has different meanings, depending on the context in which the word is used. In bulk solids handling applications, it is generally taken to mean the separation of one type of material from others, even though the materials may be substantially similar.  For example, a material is discharged from a drying operation and is then sent to a screening operation to remove over-sized (“overs”) or under-sized (“unders”) material from the “on-spec” material of a desirable particle size or particle size distribution (“PSD”).  With respect to the various bulk solids drying technologies available, only a fluidized bed operation can be used as means to classify overs and unders from the on-spec material to some degree and without a further screening or separation operation.

Material Classification Fluid Bed Drying

(Here is an example of different classifications, from left to right are unders, on-spec, and overs).

Examples of the most prevalent drying technologies available today include spray and/or flash, heated or hollow flight, belt, rotary drum, and fluidized bed dryers.  While each of these technologies has applicability in various drying applications, some provide no material classification whatsoever, with others providing a small extent of classification, and others providing even more material classification.  Certainly, there are many different equipment configurations that can be developed for any given application that can influence the material classification effect.  However, as will be discussed in the following, only a fluid bed operation can specifically be designed and/or operated to achieve material classification within the drying operation itself. 

In spray drying, a solution of suspended or dissolved solids is sprayed into a drying chamber that receives hot drying gas (“gas” because it may be air, nitrogen, carbon dioxide, or some other heated gas suitable for the application).  As the sprayed liquid droplets contact the hot gas, the water evaporates, leaving a residual solid behind.  The velocity of the drying gas (typically in counter-current flow to the solids) is controlled such that the dried residual solids fall via gravity to the bottom of the drying chamber.  The solids may be collected and discharged intermittently or continuously from the unit.  As there is some gas movement that is counter-current to the solids flow, it is possible that some very small particles (“fines”) are removed from the drying vessel and collected in exhaust gas dust removal equipment.  While, technically, this is a small degree of classification, it is more the consequence of a gas flowing in opposition to the direction of the dried solids and, with the gas velocity intentionally set at low values, the object of the unit operation is more to conserve mass from being removed from the vessel to exhaust gas de-dusting equipment and maintain the highest rate of solids flow toward the bottom of the unit operation for further processing.  In other words, the unit is not designed to provide classification to any significant degree.  Rather, it is designed to minimize classification of material within the vessel.  In some configurations, the spray drying vessel directly feeds a fluid bed dryer unit operation to complete the drying process. 

Flash drying is similar to spray drying in the sense that a solution of suspended or dissolved solids is sprayed into the drying vessel, where it also contacts a hot drying gas.  However, in this case, the hot gas and spray/residual solids are typically arranged to be in co-current fashion.  In this manner, the hot gas acts not only as the drying media, but also the pneumatic transport mechanism by which the dried material is removed from the drying vessel.  The product is then recouped via dust removal equipment (cyclone, bag filter, etc.).  In this case, it can also be seen that the technology is not a means by which a portion of the material is segregated or classified from the balance of material.

Heated or hollow flight drying technologies utilize one or more (typically two) screw conveyor-like shafts and flights that are fabricated such that there are internal spaces within the shafts/flights for the movement of a heated thermal transfer fluid (hot water, thermal oil, steam, etc.).  With this particular drying technology, the wet material is introduced into the drying operation and the movement of the heated flights move, turn, mix, and (via direct contact with the heated flights in a conductive energy transfer fashion) dry the material.  Typically, heated flight drying technology does not use a “sweep” gas (a gas passed through the internal volume of the dryer to prevent high moisture vapor content in the vessel and, therefore, to prevent internal moisture condensation), or uses very little sweep gas for this same purpose.  As such, there is little, if any, material removed from the main bulk of the product to downstream dust removal equipment.  Therefore, the unit has little or no material classification ability (and is not designed to do so).

In belt drying, the wet material to be dried is deposited on to a moving belt.  The belt may be arranged in a single-, double- or even greater number of “passes” within the dryer unit in a serpentine fashion.  The belt typically is of a mesh or perforated design such that the hot drying gas may pass through the belt and material residing on the belt.  The gas flow may be co-current, counter-current, or some other arrangement (passes through the wet material vertically/perpendicularly).  In all configurations, the drying gas is meant only to impart the drying energy necessary and is not meant to carry smaller particles away from the unit with it.  As such, it can also be seen that belt drying operations do not present an opportunity for material classification within the drying operation itself.  In fact, fines generated during the drying process may pass through the belt perforations and wind up accumulating in the bottom of the dryer requiring periodic removal.

With rotary or drum drying, a heated drying gas is introduced into a rotating shell (the “drum”) that is equipped with internal vanes or flights.  The material is fed to the dryer and is “lifted” within the vessel by the internal flights.  As the drum rotates, the internal flights reach a point where the material falls off the flight and drops via gravity toward the bottom of the dryer vessel in a “curtain-like” shower of falling material.  As the material falls, it directly contacts the hot drying gas, thereby receiving the necessary drying energy.  The material and drying gas are typically in counter-current flow to each other, although it is possible to have a co-current arrangement as well.  Since the material is falling through a moving gas stream, smaller particles (“fines”) of sufficiently-small size may be entrained in the drying gas stream and be removed from the drying vessel in a process known as “elutriation” (the separation of small particles from the main bulk of larger-sized material and exhausted with the gas).  This “dust” is then removed from the exhaust gas stream via downstream dust-recovery equipment.  While this is a form of material classification, it is not generally the intent in a rotary drum drying application to do so.  It is merely the consequence of the smaller particles being captured by the moving exhaust stream, with the movement (velocity) of the gas stream within the vessel more designed for providing the necessary gas mass rate to (a) effect proper heat transfer for the drying operation and (b) have sufficient moisture-carrying capacity for the moisture removed from the product such that internal condensing conditions are avoided.  In this sense, it can be seen that, while a rotary drum unit can achieve some small degree of material classification, this is not the intent of the operation and the unit operation is not specifically designed to classify material.

With fluidized bed drying, however, it is possible to exert a significant influence on the classifying effect via the selection of a fluidizing velocity that will result in classification of smaller particles (“unders,” “fines,” “dust,” etc.).  Additionally, design features can be incorporated into the fluid bed dryer unit that can also assist in the separation of larger-sized particles from the main bulk of material (i.e. “overs” separation/classification).  In this sense, the fluid bed dryer operation can act as a triple-deck screener (separating unders, overs, and on-size material into three distinct material streams), while concurrently acting as a drying operation.  To further illustrate this point, one should consider the act of material fluidization itself. 

In fluidization operations, a fluidizing gas (heated in the case of a drying operation) enters the dryer through its lower “plenum” section.  The gas then passes through a gas distributor to evenly-distribute the fluidizing gas over the entire fluidized area.  The fluidizing gas then passes through the bulk solids, exerting “drag force” on the surface of the particles and, with proper velocity selection, suspending the particle in a “cushion” of gas, thereby fluidizing the material.  Were all of the particles of the exact same size, shape, density (or particle specific gravity), etc., no particles would be removed from the others, nor elutriated or classified from the main bulk of material.  This, however, is almost never the case, as the vast majority of applications involve materials having distinct particle size distributions, shapes, etc. (i.e. all particles do not have the exact same fluidizing characteristics).  Therefore, at a constant fluidizing velocity, the “right-sized” particles will be suspended and the “fines”/“unders” will necessarily be classified from the balance of material, since the fluidizing velocity being used is higher than the necessary “transport” velocity of the fines/unders.  Therefore, they will be removed from the dryer unit with the exhaust gas for recovery in downstream dust-recovery equipment.  Should the fluidizing velocity be increased from the previous velocity, particles that were previously too large to be elutriated are now elutriated, establishing a new larger “cut point” particle size for classification.  In general, the lower the fluidizing velocity, the smaller the cut-point particle size, and vice-versa.  As such, the fluidizing velocity can be adjusted to directly-affect the size of particle removed (classified/elutriated).

As discussed above, at a given fluidizing velocity, the “on-size” material is properly fluidized and the fines classified from the bulk of material.  However, it is also likely that the particle size distribution of the material is such that there are particles larger than those that would be suspended by the set fluidizing velocity.  These “overs” may not fluidize as well as the on-size material and drop toward the top of the gas distributor.  As Schwing Bioset utilizes a “directional flow” gas distributor design, these larger particles are essentially “pushed” toward the discharge end of the unit, with the gas distributor acting as a transport mechanism for these larger particles.  When these larger-sized particles reach the discharge end of the unit, they may be discharged via an “underflow” arrangement, which may constitute a separate discharge stream from the dryer unit and may be kept separate from the main bulk of material discharged, thereby establishing a distinct “overs” stream from the unit.  With the on-size material discharged from the dryer via a second discharge point (typically on “overflow” weir), one can see that there are now three distinct material streams from the dryer unit – the “unders” elutriated with the exhaust gas stream, the “overs” discharged via a separate underflow discharge point, and the “on-size” material stream discharged from the overflow weir. 

With proper fluidization velocity selection and system design, it can be seen that a fluidized bed unit operation can be designed and operated such that, while acting predominately as a drying operation, can also be used to exert influence on the material such that it can be classified into two (or more) material streams.  In this respect, it can be seen that only a fluidized bed drying operation, relative to other drying technologies, can also “double” as a means by which material classification may be achieved, potentially eliminating further downstream screening steps or, at a minimum, reducing the design requirements of such downstream processing equipment.

To learn more about material classifying and our Fluid Bed Technology, please contact a Schwing Bioset Regional Sales Manager by calling 715-247-3433, email us, and/or visit our website here.


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Tags: Fluid Bed Dryer, Fluid Bed Drying, Material Handling, Material Classification, Bulk Solids Handling, Solids Drying

City of Edmonton's WWTP Truck Loading Tribulations


Written by Joshua DiValentino, June 27, 2016

The City of Edmonton’s Gold Bar WWTP saw cake storage and transfer to truck loading as a bottleneck in their plant. Current operations included storage of mechanically dewatered sludge in a Schwing Bioset push floor bunker installed in 1999. From there it was pumped to a composting operation where the product is distributed for beneficial use.  Area growth led to biosolids volumes exceeding composter capacity and a screw conveyor bypass was installed from the storage bunker to divert excess biosolids to truck loading for land application.  As biosolids production grew, it became increasingly clear this conveyor bypass was not a long-term solution, as it would take 45 minutes to load a truck.

Edmonton installed a new piston pump in the existing storage bunker to transfer biosolids to two new, 250 cubic yard capacity sliding frame truck loading silos. The silos are capable of storing enough volume of biosolids to seamlessly support plant process flow.  Each has three drop points to load two different styles of trailers, and hanging pendant controls, so the driver does not need to leave his cab during loading operations.

The plant can now easily handle the increased biosolids production and is able to load trailers in less than 15 minutes without requiring repositioning. The system improved process efficiency while minimizing O&M costs, providing more operational uptime for this 24-hour facility.

The Schwing Bioset, Inc. Field Services Team supports start-up and long term parts/maintenance of these systems. To see video of the Sliding Frame System in action or learn more about it, contact a Schwing Bioset Regional Sales Manager, call 715.247.3433, email, and/or visit our Sliding Frame Silos webpage.

Schwing Bioset Sliding Frame Silos    Schwing Bioset Sliding Frame Silos


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Tags: Sliding Frame Silos, Biosolids Storage, Biosolids Handling

Two Solutions from Schwing Bioset in June International Mining Magazine

Schwing Bioset, Inc. is excited to be featured in the Paste Supplement section of International Mining's June 2016 issue.The article discusses Schwing Bioset's recently commissioned pump solutions for backfill and thickened tailings challenges.

View the Paste Supplement section where Schwing Bioset's projects are discussed.

View the entire International Mining June issue on their website.

You can read more about these and other projects on our blog.  To learn about Schwing Bioset's Mining Solutions, contact Miguel Jahncke or visit our Mining Pumps page.




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Tags: Mining, Mining Pumps, Paste Backfilling, Mining Paste, Tailings

Schwing Bioset Wraps Up 2016 Spring KSP Pump Service Seminar


May 17, 2016

Schwing Bioset KSP Pump Training Schwing Bioset KSP Pump Training

The first two days of training are held in the classroom and cover safety, operations, maintenance, and basic hydraulics.  The third day of training provides hands-on experience where attendees train with the SBI Parts and Service, Quality Control, and Customer Service departments working directly with equipment to learn about its use, maintenance, and using it safely.  Some of the topics discussed include hydraulics, poppet valves, power packs, schematic reading, troubleshooting, screw feeders, sludge pumps, preventative maintenance, and much more.

Schwing Bioset typically offers two KSP Pump Service Seminars per year.  The next training will take place in the fall of 2016.  Training fills up fast, so please consider registering ahead of time if you are interested in attending.

Our Service Department is also available to come to your location and train at your facilities. If that is something you’re interested in, we would be happy to provide you with a quote.  Please contact Paul Katka, the SBI Service Manager, at (715) 350-6913, if you would like more information for this option.

Some feedback we received from the seminar attendees include:

"Very accomidating to everyone's needs and opinions. All Schwing Bioset employees I met at both the seminar and plant were more than decent. Keep doing what you do, wouldn't change a thing."

"Everything was very professional and well rounded."

"I liked this program. I had a good chance to understand the hydraulic system and troubleshooting. The hands on portion in the shop was also impressive. It was a very good experience!"

"The seminar was very informational. The hands on portion was very good. I learned a lot and learned how to troubleshoot on the powerpack and pump. Very successful class."

"Very satisfied with the training, the people involved and the material. Thanks for all the care and the exceptional training."

For questions about this training or to inquire about a future training at Schwing Bioset, please contact Tanya at: or


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Schwing Bioset, Inc. (SBI) held its Spring KSP Pump Service Seminar from May 10 to May 12.  The seminar was once again led by Schwing Bioset’s Quality Control Specialist, Jack Koehler.  The seminar and training is designed for Schwing Bioset customers to learn how to properly use and maintain their equipment, to help ensure they get the most out of it.  This spring, there were nine customer attendees and six of Schwing Bioset’s employees who attended.  The course builds 24 hours toward quality training and education for the attendee.

Tags: Events, KSP Service Seminar, Pumps, Equipment Maintenance

Orlando Selects Schwing Bioset over Anaerobic Digestion for Class AA Biosolids


Authored by Tom Welch, Southeast Sales Manager for Schwing Bioset, Inc., and Vic Godlewski Jr., PE, Wastewater Division Manager, City of Orlando

May10, 2016

The City of Orlando has been working for several years to move away from Class B land application of Biosolids.  The City explored use of an experimental technology that would almost fully oxidize Biosolids leaving very little residuals for disposal.  While investigating this experimental technology, the City delayed renovations to the anaerobic digestion systems at their Conserv II Water Reclamation Facility (WRF).  Ultimately it was determined that the oxidation technology was not yet commercially viable, at which point they could no longer postpone biosolids treatment improvements.  Orlando engaged the services of a Consulting Engineer to evaluate the digesters and prepare project cost estimates from simple renovation to Class A TPAD with sidestream treatment and combined heat and power.  The estimated project costs were over $40 million and climbing.  Since Orlando believes that the market is going to deliver better options than anaerobic digestion in the future, they began to look for interim options that could be implemented relatively quickly at low capital cost investment; improve their Biosolids treatment, potentially eliminate the need for land application, and not substantially increase O&M costs.  That was a tall order!

The City became aware of the Schwing Bioset process and immediately saw the potential it had to meet all of their requirements for both short and long-term implementation.  In addition, Schwing Bioset could offer conversion of the stabilized Biosolids to a licensed commercial fertilizer product.  The City staff visited current Bioset operations in St. Petersburg as well as other locations in Florida and were impressed with what they saw and with the simplicity of the process.  The City conducted an in-house feasibility study that considered Bioset and other technologies and concluded that Bioset was the preferred treatment process.

Schwing Bioset offered a Design Build approach that was very appealing.  However, due to the City’s procurement constraints this path was not available. To speed up project delivery the Bioset process equipment was purchased directly by the City and installation was competitively bid.



As shown in the photos above, the Bioset equipment is currently being installed at the Conserv II facility and is scheduled for startup in the summer of 2016.  Schwing Bioset has a sister company, Biosolids Distribution Services (BDS), that manages Class AA Fertilizer Grade Biosolids in the state of Florida.  They have marketed in excess of one-million wet tons of Class AA fertilizer in the state of Florida over the last 10 years.  BDS will be managing the Biosolids produced at the Orlando Conserv II facility when the Bioset process becomes operational.

To learn more about our Bioset process or this project specifically, contact this blog’s author, Tom Welch, and/or visit our website here: SBI Bioset Process. For other inquiries, call 715.247.3433, visit our website, or find us on social media.


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Tags: Bioset Process, Class 'AA' Biosolids, Wastewater Treatment, Biosolids Distribution Services, Commercial Fertilizer

Meeting the Growing Demands of a Successful Mining Operation – The Schwing Bioset Solution


Written by Miguel Jahncke, May 2, 2016

The San Jose mine, one of the flagship operations of Fortuna Silver Mines, Inc., located in the state of Oaxaca in Mexico, was commissioned in July 2011 and began commercial production in September 2011 at a rate of 1,000 tpd. In September of 2013, the mill was expanded from 1,150 tpd to 1,800 tpd and in April 2014, the mill was further expanded to 2,000 tpd. Expansion of the mill from 2,000 tpd to 3,000 tpd was initiated in the first quarter of 2015 with commissioning planned for July 2016.


(Shown Above: Old Plant Installation)

During the initial installation, the operation received two Schwing Bioset KSP80 pumps, one for operation and one for stand-by. As the reserves increased and the mine production and processing plant expanded, San Jose evaluated different options for handling the additional mine backfill requirement, finally deciding upon the reconfiguration of the KSP80 pumps and their installation at the new and improved Paste Plant, in a parallel arrangement. This new arrangement allows San Jose to handle double their initial paste flow capacity with no additional investment in larger pumps.


(Shown Above: New Plant Installation)

In addition to the parallel arrangement, Schwing Bioset also upgraded the Control Panel with its patented multi-pump synchronization system. This system allows both pumps to continuously “talk” and make adjustments to their stroke timing while pumping, ensuring that, regardless of the pump speed, continuous flow through the pipeline is achieved, mitigating the potentially negative effects of water hammer. 

The new system was recently commissioned and now operates as a single 4-cylinder pump with no need for additional pipeline pressure dampening to maintain smooth pumping operations, as would be expected from multiple independent pumps feeding a common pipeline. The configuration also allows for the units to be decoupled for maintenance or when plant tailings delivery is reduced, continuing operation with two cylinders to maintain the single pump flow capacity.

Further proving their versatility and toughness, the Schwing Bioset pumps were the only component that was saved from the old Paste Plant to be reutilized in the new Paste Plant. Upon completion of the 3,000 tpd expansion, the mine will produce 9-10 million ounces of silver and 52,000-53,000 ounces of gold per year, ranking the San Jose Mine among the world's top-13 primary silver producing mines.

To learn more about this project specifically or learn more about our mining backfill pumps, please contact this blog’s author, Miguel Jahncke, call 715.247.3433, and/or visit our website here: SBI Mining Pumps.


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Tags: Mining, Mining Pumps, Paste Backfilling

Bioset Demo Confirms Direction for New Class A Biosolids Equipment at Russellville WWTP


Written by Lance Bartlett, Utility Engineering Manager for City Corporation and Tom Welch, Southeast Regional Sales Manager for Schwing Bioset, Inc.

April 25, 2016


In early 2015, City Corporation, the commission established by the City of Russellville to operate the municipal water system, completed a construction project to abandon existing fixed film treatment facilities and convert the wastewater treatment plant to a denitrifying activated sludge facility.  Activated sludge technologies produce more sludge than fixed film and initial calculations predicted an increase of 6 to 7 times the current production rate when operated at the design capacity of the facility.

City Corporation had processed sludge through aging aerobic digesters and produced a Class B biosolid under 40 CFR 503 that was then dewatered and land applied to three nearby fields.  Two of the three permitted fields were no longer available, leaving only 49 acres for use.  The increase of sludge production was predicted to require around 160 acres.

The expected increase in sludge production and lack of land available for land application prompted staff to explore options.  The alternatives explored included composting, additional aerobic digesters, dryers, and the Bioset process from Schwing Bioset, Inc. (SBI). The Bioset process was selected for piloting in February and March of 2015 due to its low cost, simple operation, and the high quality Class A product that it produces.  The lone concern was with respect to the increase in volume due to the addition of chemicals, and staff wanted to get the new process up and running to obtain empirical data on sludge volume.  The engineering firm performing the preliminary study had built in a large contingency due to not being familiar with the Bioset technology and the uncertainty in sludge volume, thus raising concerns that the Bioset technology would be the proper process for the future of the Russellville WWTP.  Ultimately the volumetric increase was less than 10%, and with the Class A designation the number of outlets and demand for the material exceeds production rates.

Russellville_Bioset_3.jpg Russellville WWTP_Bioset Process_Schwing Bioset

Following that successful pilot test, in April of 2015, Schwing Bioset agreed to continue to lease the pilot machine under a monthly contract basis for the sludge handling process.  By the fall, City Corporation had a good feel for their solids production and had a great experience with the Bioset full scale pilot equipment.  Given the years of struggling with the Class B sludge process, management and staff were very pleased with the Class A process and end product and the thought of returning to a Class B process was taken off the table. With all the uncertainty taken out of the equation, staff was ready to make a decision and chose to move forward with a permanent Bioset installation.  City Corporation and Schwing Bioset continue to operate under a contract that allows City Corporation to operate the pilot unit until the permanent unit is installed and operational.  This arrangement allows City Corporation to manage their sludge and operate the plant in accordance with the design parameters, keeping the facility in compliance with the ADEQ, which otherwise would not be possible.  The new facility is anticipated to be operational in mid-October 2016.  The current digester will only be used as a sludge holding tank, thus reducing the power consumption needed for complete aerobic digestion to meet Class B standards, and allowing just WAS sludge to be converted to Class A EQ fertilizer through the Bioset process.

To learn more about our Bioset process or this project specifically, contact this blog’s author, Tom Welch, and/or visit the SBI Bioset Process page. For other inquiries, call 715.247.3433, visit our website, or find us on social media.

Download Our  Bioset Process Brochure


Tags: Bioset Process, Class AA/EQ Biosolids, Wastewater Treatment, Lime Stabilization, Bioset Demo

Larry Larson Retires from Schwing Bioset


April 7, 2016

The Schwing Bioset team would like to congratulate Larry Larson on his retirement and thank him for his years of service.

Larry has been an invaluable asset to our team for 27 years (to the day!). He has helped the parts department to be one of the best in the business and helped to prepare the department to continue to strive for excellence into the future. His dedication to push us to the next level will be greatly missed.

Larry has been a friend and a mentor to many throughout his years with our company.

Congrats Larry and enjoy your retirement!

LarryLarson-2.jpg  LarryLarson-3.jpg

Tom Anderson (Schwing Bioset President) and Larry Larson


For your parts needs going forward, please contact Jeff Joy ( or Brad Dopp ( at 715-247-3433. 


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Tags: Announcements, Events