Sustainable desalination technologies are the smart solution for producing fresh waterudand preserve the environment and energy by using sustainable renewable energyudsources. Membrane distillation (MD) is an emerging technology which can be drivenudby renewable energy. It is an innovative method for desalinating seawater and brackishudwater with high quality production, and the gratitude is to its interesting potentials.udMD includes a transfer of water vapor from a feed solution to a permeateudsolution through a micro-porous hydrophobic membrane, rejecting other non-volatileudconstituents present in the influent water. The process is driven by the temperatureuddifference along the membrane boundaries. Different control applications andudsupervision techniques would improve the performance and the efficiency of the MDudprocess, however controlling the MD process requires comprehensive mathematicaludmodel for the distributed heat transfer mechanisms inside the process. Our objectiveudis to propose a dynamic mathematical model that accounts for the time evolution ofudthe involved heat transfer mechanisms in the process, and to be capable of hostingudintermittent energy supplies, besides managing the production rate of the process,udand optimizing its energy consumption. Therefore, we propose the 2D Advection-Diffusion Equation model to account for the heat diffusion and the heat convection mechanisms inside the process. Furthermore, experimental validations have provedudhigh agreement between model simulations and experiments with less than 5% relativeuderror. Enhancing the MD production is an anticipated goal, therefore, two mainudcontrol strategies are proposed. Consequently, we propose a nonlinear controller foruda semi-discretized version of the dynamic model to achieve an asymptotic trackingudfor a desired temperature difference. Similarly, an observer-based feedback controludis used to track sufficient temperature difference for better productivity. The secondudcontrol strategy seeks for optimizing the trade-o between the maximum permeate flux production for a given set of inlet temperatures of the feed and the permeate solutions,udand the minimum of the energy consumed by the pump udow rates of the feedudand the permeate solutions. Accordingly, Extremum Seeking Control is proposed forudthis optimization, where the pump udflow rates of the feed and the permeate solutionsudare the manipulated control input.
展开▼
