KSB provides new energy to a 40-year-old combined heat and power plant

One of Sweden's largest combined heat and power plants

Händelöverket in Norrköping was built in 1982 and is today one of Sweden's largest combined heat and power plants. At the E.ON-owned combined heat and power plant, residual products such as waste wood chips, forest fuels, rubber and other waste are burned. The energy is converted into electricity and district heating, but also into process steam which is used to produce the fuel ethanol. By producing both electricity, heat and steam at the same time, 90% of the energy in the fuel is used.

A necessary replacement of pumps

For 40 years, two split-case district heat pumps have been responsible for pumping out hot water into the district heating network from Händelöverket. The pumps, which were designed in the 1980s, are bottom-suction pumps and differ from modern pumps in that they do not have in-line inlets and outlets. Instead, they are built with inlets from below and outlets to the side – unusual design details today. In connection with a changed mode of operation of the district heating system, new pumps were needed that were adapted to the new mode of operation and therefore a replacement of the pumps was necessary.

To ensure that the district heating could continue to reach businesses and households, new pumps were procured by E.ON to replace the old pumps. The requirement was that the new pumps should be installed in the same places as the old ones and connected to the existing pipe system, in order to minimize disruption to the business. It was not an easy task, but thanks to a similar solution that KSB had previously delivered to a pumping plant in Canada, a time- and cost-effective solution could be presented.

The solution was found in Canada

It turned out that both the construction drawings and the castings from the pump plant in Ontario, Canada, matched Händelöverket's specifications perfectly, since the Canadian pumps were also bottom-suction. KSB's modern RDLO design details brought several improvements, such as an optimized flow, smoother operation and a more reliable power transmission. As the pumps were originally designed for potable water, some modifications were required to adapt them to the higher density of the hot district heating water at the combined heat and power plant.

- That we could adapt the pumps to meet both old and new technical requirements was a decisive part of the project. It shows our ability to deliver flexible solutions that meet the customer's needs and underlines how valuable our long experience is to quickly reach the goal, says Frida Edling, project responsible salesperson at KSB.

A long-lasting solution with new splitcase pumps

The new RDLO pumps that were installed are so-called split case pumps, which are capable of pumping out over 3,000 cubic meters of water per hour – per pump. The pumps offer an almost maintenance-free and long-lived solution that meets E.ON's strict requirements for energy efficiency and operational reliability. Thanks to their wide range of applications, they are a popular pump type and are used for everything from district heating and cooling water to distribution pumps at waste water treatment plants – in other words, where large liquid flows are required.

- It was very important to us that the pumps fit into our current system and that we have access to quick inspection if needed. We have good experience with KSB's pumps and their service technicians, and therefore we felt confident in choosing them as a supplier, says Jonas Viklund, project manager at E.ON.

A successful project is spelled collaboration

The preparations for the extensive pump replacement at Händelöverket have been a long-term project that has been ongoing for several years. During this time, engineers and technicians from E.ON and KSB have worked closely together, where specifications and technical data have been analyzed to ensure the right type of pumps and their power. With careful preparation, the installation of the pumps at Handelöverket also went smoothly and quickly, with no interruption in operation during the actual replacement.

Jonas, who has also visited KSB's factory in Halle, Germany, thinks that the collaboration has worked well.

• KSB has delivered on time and fulfilled our wishes and requirements from the start. We have felt secure in their ability to meet our expectations for support, process and technology throughout the project, he says.
• All projects have their challenges, of course, but with our long and accumulated experience from international projects, we have developed a solid ability to handle and solve even the most complex projects, concludes Frida.

Success factors during the project:

• Several joint meetings on site at KSB's factory in Halle, Germany, and at Handelöverket have been favorable to the project.
• The close dialogue between KSB's engineers from both Germany and Sweden as well as E.ON that went on for several years before the project.
• Clarity in the specifications for the project.
• Minimal modification thanks to previous experience from similar projects, which leads to a more cost-effective process.
• Long-term and good customer relationship where KSB continuously provides support and service.