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Why do we all (at least most of us) like candy, soda, cookies and cake? All these products contain sugar which makes it taste real good. But where does this sugar come from? All green plants make sugar through photosynthesis. Of all plants, sugar beets and sugar cane contain the greatest quantities of sugar; that’s why we usually use these two plants to extract sugar. In this blog we focus on the processing of sugar beets and the role that Bronkhorst flow meters have in this process.

Convergence Industry B.V. is a supplier of customized measurement and control systems for liquids and gases. In the process of getting sugar from sugar beets one of the customers of Convergence discovered that by using membrane filtration, it was possible to extract more components out of the sugar beet than sugar alone. For this a customized lab scale system for nano filtration was used.

Membrane filtration

Membrane filtrations is a high-quality purification process using sophisticated techniques. How does this work? A simple explanation of membrane filtration is comparing it with making coffee. If you pour water in a coffee filter filled with coffee beans, you want coffee as a result without the shell of the coffee bean. That’s what the filter is for. On another level this is similar to water filtration where you want to filter the ions so you can make drinking water out of seawater. As simple as that!

Collaboration with Convergence for membrane filtration

For the membrane filtration a ‘Convergence inspector Colossus’can be used. This is a fully automated customized lab scale system for nano filtration which makes it interesting. Felix Broens (Chief Technology Officer of Convergence Industry B.V.) explains how this system works:

”The nanofiltration system is fed with water in which a phosphatefree anti scalant is dosed. Using a high pressure pump the system is pressurized, causing a part of the water to pass to the membrane (permeate). The part of the water that cannot pass through the membrane (retentate) is led back to where the water has been fed. An extra pump in the recirculation conduit causes a higher velocity across the surface of the membrane, which reduces pollution on the membrane itself. The permeate can eventually be used as clean water for different applications.”

“The anti scalant is used to prevent scaling on the membrane, by forming a complex of metal-containing ions, which keeps them in the retentate stream so that they can be led out of the system. Because of using a phosphate free and biodegradable anti scalant, it doesn’t have any harmful effects on the environment.”

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Bronkhorst flow meters in membrane filtration

The heart of the nanofiltration system is a Bronkhorst Coriolis mass flow meter for controlling the process. It uses a Coriolis flow meter because it can measure density as well, which is important in case of sugary solutions. The flow meter is placed at the ‘clean’ side of the process, so behind the membrane where the permeate flow takes place (the purified product flow). The degree of separation of the membrane can be influenced by both flow speed and pressure. And thus a Coriolis flow meter with a wide range is the best option to cover a large test range.

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This Convergence system has made it possible for their customer to improve their process enormously. Before using the Convergence system it was a manual process that was rather time consuming and not always accurate. Nowadays the whole process is automated using client-specific Convergence software which makes it possible to accurately control the Coriolis mass flow meter with the pump and therefore, the permeate flow can now be controlled accurately and fast. This results in a good reproducibility, reliability, datalogging and shorter lead times for the experiment compared to as it was before. This customized lab scale system makes it possible to generate a sufficient amount of residue for testing purposes without making it necessary to upscale the process to a pilot plant.

Check out the Coriolis flow meters available for this application: https://www.bronkhorst.com/int/products/liquid-flow/mini-cori-flow/

Contact Convergence for more information about membrane filtration https://www.con-vergence.com/