Efficient, sustainable and above all reliable
In a hospital, reliability and quality are more important than in any other environment. There, you always opt for proven reliability. In Aachen, Germany, Grundfos' MIXIT solution is now making its mark.
In the university hospital Uniklinik RWTH Aachen, a solution was researched to accommodate a new conditioned facility for the storage of laboratory samples for blood preservation and other biological products. This new storage facility needed to be permanently cooled using modern technology, be very reliable and have an optimally transparent process. And the heat produced during cooling has to be transported.
Ralf Kühn heads the Refrigeration Department of Uniklinik RWTH Aachen. Together with project manager Wim Blättler and Managing Director Marco Roubrocks from Roderland and Julian Betzer from Grundfos, he shows us where and how the MIXIT solution does its job. Installation company Roderland took care of the installation, the engineering was done by the external engineering company SIWG GmbH. A whole chain of parties, within which choices and activities were allocated.
Energy guzzler
In the old situation, there was a room with over sixty freezers in it, cooling all kinds of laboratory samples at a temperature of minus eighty degrees Celsius, round the clock. The heat production that this entailed, required a considerable extra cooling effort. In short: that set-up was a huge energy guzzler, producing a lot of noise. Moreover, and more importantly, it was impossible to monitor all freezers always keeping the right temperature.
The desired outcome, having to be commissioned through a competitive bidding, was a system that is secured against failure, displays the relevant cooling data in a clear and organised dashboard, that can be controlled efficiently and ensures less energy loss. This challenge was put before Marcel Schunk from SIWG GmbH and after a feasibility study, the MIXIT solution from Grundfos was chosen.
Traditional or not
Schunk recognized that the main decision to be made, was to choose between a traditional mix loop or the MIXIT solution. "A traditional mixing group is comprised of several separate components with an additional separate power meter, whereas the MIXIT solution integrates everything into one system. The best choice deemed to be the integrated solution. It came out as the best option in meeting all requirements in a compact and integrated solution, and it resulted in significant time savings in all areas: The design and selection of the complete solution during the planning phase was very simple, as was the installation of both the MIXIT and the accompanying circulation pump MAGNA3. And for the user, the operation is very intuitive and easy."
Nothing but advantages
The colleagues from the Refrigeration department also immediately noted the benefits of the new solution. "The system is very easy to operate, and all the important information is displayed on a screen. You are able to set all parameters on this screen, with immediate feedback so that you can instantaneously see the effect of your settings," says Kühn. The functionalities for energy metering are included and the integration in the building management system is effortless thanks to the built-in bus communication. In the MIXIT, the controller, check valve, control valve, actuator, throttle valve, differential pressure valve, temperature controller and sensors are all integrated in one plug-and-play product. The system supports cooling as well as heating applications.
The MIXIT offers a solution that is much faster and easier to design and install, and is also cheaper. Many components are integrated so you need to install far fewer separate parts, which is more effective overall.
Challenge
An crucial challenge was the limited available space. Thus, the solution had to be compact and at the same time offer all the functionalities needed to operate the mixing loop efficiently, plus those for energy measurement and optimisation. Marcel Schunk from SIWG says that before he knew of the MIXIT solution, he always opted for a traditional mixing loop – with many separate components plus a separate energy meter.
"But it requires quite a bit of space to install all these individual components. In this situation, that was difficult to achieve. The MIXIT offers an efficient and compact solution that saves a lot of space."
Wim Blättler from Roderland says that during the construction phase, close consultation took place with the client about optimising the location for the new cooling centre and the way in which the technology was led from there to the basement. The system is laid out redundantly and a nitrogen-based emergency cooling facility has been installed. We are invited to take a look in the basement of the immense building, where the MIXIT is installed. We are immediately aware that this is not the first Grundfos product to be used. "We are very happy with Grundfos," Kühn states. "We are very satisfied with the quality and service we experience using their products. That, of course, made us feel very confident when this solution was proposed."
Julian Betzer from Grundfos and Marco Roubrocks from Roderland GmbH inspecting the diagram of the storage facility for the sample storage
In the basement
In the basement we see the two installed systems. Kühn: "The pumps are frequencycontrolled and connected to the MIXITs. When we set the MIXIT, we see the pumps respond immediately. There is a real-time feedback and because of that immediate response, it functions very energy-efficiently."
The MIXIT and the MAGNA3 can communicate with each other as well as with the Grundfos GO app. With this app, you can commission both components, adjust the operation and continuously monitor the result. And because of the enormous number of data points in the system, you always have real time information on how the installation is functioning, and are able to intervene swiftly if the system is not working optimally. Which in turn ensures less failure and service costs. Blättler: "At the same time, everything was laid out very old-school and secured three times."
Accurate
Kühn is happy with the solution. "We, as users, have a good overview of the parameters. Once the temperature is close to the target value, the cooling system switches down. You are able to control very accurate and tight." He refers to it as a top product. "We could get even more out of it than we already do, and even now, it already reduces the energy consumption enormously. The cooling yield is controlled very accurate and clear, with minimal spend."
Julian Betzer from Grundfos proudly states: "The MIXIT offers a solution that is much faster and easier to design and install, and is also cheaper. Many components are integrated so you need to install far fewer separate parts, which is more effective overall." SIWG consultant Schunk estimates the costs to be about 20% lower compared to a traditional mixing loop, just during design and installation alone. The energy savings are added on top of that.
We are very happy with Grundfos. We are very satisfied with the quality and service we experience using their products. That, of course, made us feel very confident when this solution was proposed.