A new solution at a water storage tank in the supply area of Aarhus Vand regulates the flow into the tank with a needle valve. It is a dynamic, low-noise solution, and the valve is fitted with a control system that provides all options of operation both manually and via network connection.
Water storage tanks ensure water for consumers
One of the plants in Aarhus Vand’s supply area has three storage tanks for clean water. The storage system ensures that enough water can be supplied to consumers – also in case of fluctuations in consumption.
At this plant, there are two tanks of stainless steel and one of concrete. Water is drawn from another area and into the three tanks from where it is discharged into the supply area.
Reduction of the flow into the water storage tanks
The water enters the system with high pressure, and valves regulate the flow into the tanks.
Previously, the flow into all three tanks was regulated with butterfly valves. This was extremely noisy, and excessive noise and vibrations resulted in a poor work environment, wear and tear, and a shorter service lifetime of the installations. When the installation regulating the water flow into the concrete tank needed repair, Aarhus Vand took the opportunity to find a new and better solution.
Significant noise reduction
In collaboration with AVK, the utility chose a new solution where supply to the tank system is reduced with a needle valve. Due to the short face-to-face dimension, the needle valve could be built in without having to modify the pipe gallery, and the electric actuator that is built on could be connected to the existing control system, so no changes to the electrical installations were required. This was a major factor in keeping the costs of the project down and a contributing factor in the choice of this particular solution.
The valve is fitted with an AUMA Profox actuator, which regulates via Aarhus Vand's existing control system and can be operated via an app or computer, or with a handwheel so it can be operated even when there is no power.
Noise and vibrations from the installation are significantly reduced compared to the previous setup. "The design of the valve and the fact that AVK customises the valve to match the hydraulic conditions of the individual installation means that there is no noise. For example, 112 m3 can flow in completely silently," says Anders Sørensen, Operations Assistant at Aarhus Vand.
The project
Noise was a major issue with the previous installation, resulting in a poor work environment. This is often the case in old facilities, where equipment, acoustics and valves not tailored to the installations play a role, along with several other factors. The new solution with an AVK needle valve does not only benefit operation of the storage tank – it has also created a better work environment.Anders from Aarhus Vand is pleased with the solution, and he sees opportunities for similar installations to be relevant elsewhere in the supply area:
"It's a really good solution here at the plant, and now that we've tested it, we can see that it's something we can also use elsewhere. But it has required us to get to know the solution, and therefore it has been great to have AVK on board. We describe our problems, and then together we find the best solution."
Needle valves
AVK needle valves are designed for throttling and regulation even at very high flow rates and at high as well as negligible differential pressures. The valves allow for precise regulation.
Aarhus Vand
Aarhus Vand is one of Denmark's largest water utilities. They produce 15 million m3 of drinking water annually and treat 35 million m3 of wastewater. The distribution network consists of 1500 km of water pipes and 2800 km of wastewater pipes, supplying a total of 350,000 residential and commercial customers.
Read more about Aarhus Vand