3ω sensing in dynamic contexts

Filtering water and other fluids is a key component in a huge number of industrial processes, including drinking water purification, wastewater treatment, and resource recovery. The Center for Membrane Technology (CMT) at Aalborg University (AAU) has recently been formed to investigate and improve on all aspects of membrane technology to develop better filtering and water processing methods, leading to easier access to potable water, decreased water waste in industrial processes, and harvesting of valuable products. The present project aims to develop algorithms and advanced signal processing to measure key variables in filtration, such as fluid flow speeds and fouling build up on or near the surface, centered around the so-called 3ω measurement method. In this we will make a membrane electrically conductive and measure its thermoelectrical response to an applied alternating current to provide information about the surroundings. This will allow for in-depth understanding of mechanisms of fouling formation and can potentially serve as an operational control parameter for filtration. We aim to develop novel low-price efficient measurement devices based on the same principle, which can be used outside well-equipped laboratories.