Instrumentation specialist Baumer develops sensors together with customers to meet specific requirements, such as flow and temperature sensors for filter monitoring applications in the dairy industry.
For example, Homann, part of the Müller Group, manufactures a range of dairy products including yogurts, milk drinks, mayonnaise and salad dressings. Baumer has helped Homann achieve its goal of maximising process optimisation in the production processes with monitoring sensors.
Today, many dairy foods such as yogurts, milk drinks and quark are enriched with additional protein to support the build-up of muscle.
Production of dairy protein can be optimised if filtration processes are monitored using the right sensors. The basis for proteins that can be used for food fortification is provided mostly by whey or skimmed milk. They need to be filtered step-by-step in order to increase protein concentrations. The objective is to obtain a concentration with as high a protein content as possible. That is then dried and further processed.
This process is very energy-intensive, and its effectiveness largely depends on the condition of the filter. Calorimetric flow sensors can facilitate the monitoring of the condition of the filter, which helps to optimise the quality and cost-efficiency of protein extraction.
Cross-flow filtration technology is usually the preferred option for filter units used in the dairy industry. To increase the protein content in milk or whey, the media, the so-called feeds, are typically pumped through filters until the remaining concentrate reaches the desired dry mass.
Usually, temperature and pressure measurement indicate the effectiveness of the filtration pumps (and therefore the filtration process). Pressure values are measured before and after filtration and compared to draw conclusions about the effectiveness of the filter and the extent of clogging.
However, a better and more direct option would be to measure the flow rate of the medium, to know for sure how the filtration process is working. If the flow rate is too low, the filter clogs up faster and needs to be cleaned or replaced. When module batteries are connected in parallel, shifts and variations in flow patterns are a problem. If the flow rate is too high, the permissible pressure loss per module is exceeded and the modules telescope.
At the same time, temperature is another important factor. Temperatures of approximately 50degC favours filtration without denaturation of the thermo-sensitive whey proteins.
Thermal flow sensors, such as Baumer FlexFlow, are an effective, viable and cost-effective solution for filter monitoring, as they measure not only the temperature, but also the flow rate, based on the calorimetric measurement principle, according Baumer. They have no moving mechanical parts, and are virtually maintenance-free to allow for reliable monitoring of the cross-flow filters for many years. They have IO-Link and, depending on settings and connections, either two switching outputs, or one switching and one analogue output (4-20 mA/ 0-10 V).
All models are temperature resistant to 150°C and thus compatible with CIP (Clean-in-Place).
Just about every cycle in dairy product processing requires CIP. This reproducible process must precisely define detergent dosing, regardless of pressure and or temperature variations. At Homanns’ CIP installations in Bottrop, dosing was improved thanks to Baumer’s new CombiLyz conductivity sensor. Its response ensured precise measured results at a maximum deviation of <1%. The measuring connection of the inductive sensing element provides a 6.6mm wide channel which will tolerate fabric or solid-containing media.
Frank Piatkowski, application and process engineer at Homann, said: “Baumer’s CleverLevel is the one-sensor solution for different media. Since deploying these sensors, we have seen a significant reduction in technical malfunctions.”
“Baumer products will be part of our considerations when we invest in new, state-of-the-art CIP installations, and we appreciate that these innovative sensing solutions help us achieve our objectives of optimisation, despite the increasing complexities of our processes.”