From outsider to established global player
How wastewater pumping and grinding technology made in Essen/Oldb. is taking over the world

If anyone used the term “Vogelsang pump” in the 1980s, everyone in agriculture knew they were rotary lobe pumps. And these were automatically assigned to the innovative company based in Essen/Oldb. The Vogelsang positive displacement pumps were used almost exclusively in agriculture at that time, until some bright employees of sewage treatment plants became aware of the small, powerful pumps and the triumph of Vogelsang products in the sewage industry in Germany and around the world began...

When Helmut Vogelsang invented the elastomer-coated rotary lobe pump in 1970, his company was still largely focused on agricultural technology, and there were hardly any touchpoints with the sewage treatment sector. When a few farmers started to use sewage sludge as fertilizer roughly 15 years later, the sewage treatment plant operators saw that the pumps on the farmers’ tankers allowed them suck the viscous sewage sludge even through empty hoses and pipes. That would have been impossible with the centrifugal pumps and progressive cavity pumps widely used in sewage treatment plants. The fact that the Vogelsang pump also took up very little space and offered reversible directions of flow convinced early adopters among the sewage plant operators to use them as mobile pump units. After all, sludge comprising human fecal matter is very similar to the liquid manure used in agriculture, which is made up of fecal matter from farm animals.

Vogelsang only had to consider one difference, namely that pumps in sewage treatment plants run significantly longer than in agricultural applications. The standard seal was not designed for this. The solution was an oil-lubricated mechanical seal brought to market in 1987 with the I series for industrial applications. This allowed Vogelsang to offer this industry a solution superior to previous pumps, and wastewater technology grew to become a second revenue stream for the company after the agricultural sector.

90s: Rapid development

In the nineties, multiple developments and products followed in rapid succession – among other things, because university graduate Hugo Vogelsang modernized production processes as well as research and development after joining the company. Lessons learned from cooperating closely with customers also inspired Vogelsang’s technicians with new ideas. For example, the complex maintenance work required in legacy pumps cost sewage treatment plant operators a lot of time, as they had to be removed completely and disassembled to replace parts. Since the first Vogelsang pumps with the QuickService principle were introduced in 1994, this can be done in place and without disassembling the pump. That reduced the workload for replacing wear parts from up to one day to roughly an hour – a revolutionary approach that helped Vogelsang to attract thousands of new customers.

Sewage specialists for expert customer advice

Expanding the customer groups and applications for Vogelsang pumps also increased the need for consulting services. More and more plant operators and engineering offices asked increasingly complex questions that could only be answered by people with appropriate industry expertise. To meet this demand, Vogelsang started building a dedicated sales team with sewage expertise in 1994.

A new type of cutter impressed the sewage practitioners

Size reduction of solids in liquids is another link between the agricultural and wastewater sectors. With the new RotaCut wet cutter, originally developed to protect pumps in agricultural applications, Vogelsang presented a completely new approach to a widespread problem in 1992. Coarse matter like film residues or pieces of wood brought agricultural pumps to a standstill. The wastewater sector mostly deals with smaller, finer coarse matter, including Q-tips (cotton buds), hair, toiletries and textiles  that impede the flow. RotaCut, equipped with a hydraulically driven cutting device and a heavy material separator, chops down this floating coarse matter with unprecedented reliability and was therefore far superior to the macerators used in many sewage treatment plants.

And it was able to do so not only because it does a better job of preventing layers in digestion towers,  it also facilitates and improves sludge thickening and dewatering. Then as now, any service and maintenance work required can be performed on-site by the operator’s own personnel. After the cutter head is lifted, the cutting screen and cutting blade are freely accessible. On the other hand, macerator cutter heads had to be removed and often even sent in for repairs. It could take several weeks to get them back.

There were only two challenges with using RotaCut as a wet cutter in sewage treatment plants. The additional hydraulic power unit required and the large Cyclone heavy material separator, which worked well but was awkward to install. This is why Vogelsang introduced the RotaCut Inline, fitted with a geared motor, in 1994. Since then, thanks to its slimline design, with inlet and outlet sides directly opposite one another, RotaCut units can now be installed in place of a short straight piece of pipe. That marked the start of a highly successful development. Today, the RotaCut concept is recognized by many in the market as the state of the art for sludge treatment.

A milestone for rotary lobe pumps: The HiFlo rotary lobe

Just two years later, the Vogelsang developers solved another cross-sectoral pump design problem, revolutionizing the market for rotary lobe pumps. Where compensators were previously required to balance the characteristic pulsation of the pumps,  the new Vogelsang HiFlo rotary lobe now prevented vibrations in the pipe.

The inventors had been working on the idea of giving the lobes an internal spiral shape, to allow the pumping chambers to open and close slowly, preventing pressure shocks. The economic production of these lobes with the technical possibilities of the
that time was a special challenge, which was mastered with investments in state-of-the-art machine technology. This was a stroke of genius, since it allowed the new pulsation-free HiFlo rotary lobes to match the performance of the progressive cavity pumps that had previously been considered smoother, with their low-oscillation and low-vibration conveying.

And Vogelsang optimized the products even further: The latest HiFloplus lobe variant achieves pulsation-free operation unheard of outside centrifugal pumps.

Products like these made it easy for the company to grow on the German wastewater market. In addition, Harald Vogelsang, who joined the company in 1997, promoted international activities and laid the foundations for the rapid establishment and expansion of international subsidiaries. The first branches were established in the USA, the UK, France and Italy. There are now own companies and employee teams in 25 countries.

During this period, development work started on an automatic cutting blade adjustment system for the RotaCut wet cutter, which was now well-established in sewage treatment plants. While manual adjustment of the cut control for the blades does not take much time, the Automatic Cut Control (ACC) introduced by Vogelsang in 1999 still represents a significant reduction of the workload, especially for operators of unmanned sewage treatment plants. Ultimately, that not only eliminates the need for manpower on the RotaCut itself, but also the machine and all components connected with it no longer have to be switched off.

A solution for the wet-wipe problem

Since the early 2000s, Vogelsang’s development department has also been working on designing a twin-shaft grinder as an alternative to the RotaCut. The machine allows biogas plant operators and the food industry to shred coarser material economically, e.g., fruit and vegetables, or abattoir waste.

The new XRipper’s power is based on the counter-rotating tooth rollers – intermeshing, contactless ripper rotors, that allow low-viscosity fluids to pass largely unhindered, while solids and coarse matter are radically shredded to a non-problematic size. Vogelsang later advertised this feature for the wastewater segment, as the industry increasingly battled clogging and entangled material in sewers and pumps due to the increasing popularity of wet wipes. In contrast to toilet paper, these wipes, made of tearproof non-woven material, do not dissolve. In spite of this, some manufacturers still describe them as flushable or do not instruct users to dispose of them in domestic waste.

The XRipper very soon proved itself an effective solution for shredding coarse matter of this kind in wastewater, so Vogelsang launched XRipper variants developed specifically for use in sewer systems at IFAT 2014, such as the particularly compact inline variant for installation in tight shafts and pump stations, the XRipper Pipeline (XRP), and the XRipper XRC for installation in open sewers, or upstream of inlets or inflows in shafts and pits. Like the pumps and the RotaCut before them, these XRippers were also based on the QuickService principle. That means that the motor, gearbox, seals and Ripper rotors in the XRipper Pipeline (XRP) can be removed upwards as a single unit, while the machine body remains firmly screwed into the pipeline. The XRipper XRC is simply lifted as a complete unit from the sewer, shaft or pit via a rail system, also called the Sewer Integration Kit (SIK), instead of having to send an employee down the shaft to the cutter.

Due to the great success of both models, the XRipper XRG was added to the XRipper family in 2018. With flow rates of over 3,000 m³/h, it is a true giant thanks to the high-capacity units added on either side. They let high volumes of wastewater flow through, while the coarse matter and waste are delivered to the Ripper rotors by two clearing units. The XRG is also designed to allow the entire functional unit to be removed upwards for maintenance and service work. Thousands of customers now trust the XRipper and benefit from its maintainability.

Disintegration: A step into a new dimension

In the meantime, an entirely different technology has found its way into Vogelsang’s range: the BioCrack electrokinetic disintegration process for breaks up agglomerations of dead organic material and bacteria at a microscopic level. By passing a high-voltage field with tens of thousands of volts, the nutrients in the medium become far more accessible for the bacteria to be fermented, the breakdown of the organic components improves and the gas yield of the digestion tower rises. If used in sewage treatment plants without anaerobic sludge stabilization, the energy requirements for aeration – usually a major cost factor, so even minor improvements lead to major savings – are decreased thanks to the reduced viscosity of the sludge. Another  advantage of the BioCrack is the easier dewatering of the remaining sewage sludge, leaving less of it to dispose of.

What does it cost? Compared with other disintegration processes, the BioCrack is less expensive to purchase and run, for a faster return on investments.

Reinventing the rotary lobe pump principle

Having already sold thousands of rotary lobe pumps with HiFlo lobes, including to customers in the sewage segment, the launch of the innovative IQ series in 2012 was another milestone in the history of the rotary lobe pump. With this innovative design, the Vogelsang design engineers halved the number of key spare parts. That brought dramatic savings in costs and workload, as replacing all wear parts in the pump chamber only takes half the time of conventional rotary lobe pumps on the market. This is because access to the lobes, wear plates and seals is far more direct, and even the housing of the pump chambers can be replaced without disassembling the pipe. In addition to this, IQ pumps are easy and quick to drain, and customers from the wastewater segment benefit from the variable connectors that allow the pumps to be installed in a wide range of positions without major modifications to the system.

Understanding needs, thinking ahead and contributing innovations

True to its motto of “Leading in Technology,” Vogelsang always sees its machines from the customers’ perspective and considers their needs as part of its ongoing research and development. A customer-driven approach is the key to market leadership and the reason our pump, wastewater grinder and disintegration technology is in such high demand worldwide in the wastewater segment. Of course, we are also responding to the requirements for wastewater 4.0, and offer the corresponding control technology and software for each of our innovative machines, whether as a stand-alone solution or in a network with other components.

“Innovation has been our driving force since the company was founded.
Continuously developing ideas and products is what makes us successful.”

Harald Vogelsang