Municipal wastewater treatment is needed everywhere. Even though valves are just one part of the process, they actually play an important role in making the whole process efficient. When the valves are chosen correctly, and they fit the process needs accurately, other parts of the process like pumps wear out less quickly. This was the case at the municipal waste water treatment plant in Salo, Finland.
The flow of municipal wastewater is rarely regular, which was also an issue for the customer in Salo, Finland. The flow stops for a couple of hours during the night, and this can be challenging for the process equipment. Even more demanding is the sand, which needs to be separated before it affects the process equipment. If the sand is well separated, it will lead to direct cost savings, especially with maintenance costs.
Many factors affect the sleeve lifetime: the rubber material of the sleeve; the chemical composition and other properties of the slurry; and process conditions such as the temperature, pressure, valve size, cycle frequency, etc. The lifetime of a sleeve depends on the customer’s process. In this application, the sleeves have only been changed a couple of times during the valves’ whole lifetime, which ended up being as much as 37 years. Even after all those years, the valves were still working well, but the customer decided to change them before any problems occurred. The new valves were installed in 2022.