Used For Seawater Desalination Of Pervaporation Membrane Module Design And Experimental Research

With the rapid development of our country’s economy, the excessive development and utilization of freshwater resources and increasing water contamination, lead to the issue of water shortage more and more prominent. In order to alleviate the tensions, obtaining fresh water from seawater resources technology has been widespread attention and researched. Traditional desalination technology due to its defect makes them further development in the field of seawater desalination has been curbed. Pervaporation, as a newly developed desalination technology, a combination of thermal method and membrane method of two kinds of desalination technology advantages, is potential in the field of desalination technology. After many years of research, pervaporation membrane has the characteristics of high flux and high interception rate,but the practical application of pervaporation desalting is infrequent.Therefore, this paper designs a new type of plate-frame membrane module, laying the theoretical foundation and accumulating experience for the industrial application of pervaporation desalination.The properties of the sulfonated heterogeneous membranes used in the membrane module were characterized and tested. The effects of operating parameters such as different temperature, concentration and vacuum pressure on the permeation flux were investigated. The long-term pervaporation experiments were carried out by pre-treated seawater, and the composition of the surface contaminants was analyzed. It was found that the main pollutants on the membrane surface were carbonate and sulfate. For the membrane fouling to explore, with different types of acid as a membrane cleaning reagent, found that hydrochloric acid (pH = 2)cleaning can make the membrane flux to the greatest degree of recovery.In view of the undesirable flow state inside the flat membrane module, the FLUENT fluid simulation software was used to simulate and improve the experimental design of the structure of flow channels in the plate-frame. Finally, the structure of flow channels with good water distribution was obtained. The simulation results are verified by experimental methods. The conclusions are consistent.In accordance with the simulation results and the actual situation, the structure of the entire membrane module is designed, and the membrane module with complex flow structure is prepared by 3D printing technology. A set of pervaporation system is set up with the membrane module as the core, and the processing capacity of the device system was evaluated. The seawater is treated in the stable state of the device, and its water production up to 80L·d-1.