Arash Khosravi

Membrane processes are considered one of the effective methods for seawater desalination due to their higher efficiency and fewer limitations compared to other separation methods. However, the fouling of membranes poses a significant challenge to the progress of these processes. To address this issue, chemical cleaning has been explored as a potential solution to prevent membrane fouling. In a recent research study, three composite membranes of mullite, feldspar, and zeolite were developed using the extrusion method. These membranes, named MZF10%, MZF20%, and MZF30%, had varying compositions of (10-80-10), (10-70-20), and (10-30-60) respectively. After subjecting the membranes to a filtration and purification process of seawater for 180 minutes at a pressure of 3 bar, membrane fouling and a subsequent decrease in permeability flux were observed. The extent of reduction in permeability flux was calculated for all three membranes, and it was found that the membrane with a composition of (80-10-10) exhibited the highest level of fouling. Therefore, this particular membrane was selected for further research and the subsequent cleaning process. Backwashing, a form of physical cleaning, was employed as the initial step in the cleaning process. It was observed that backwashing contributed to approximately 4% recovery of the membrane's initial permeability flux value. Following physical cleaning with various detergents, chemical cleaning was conducted using different scenarios. The cleaning agents used in this study included sodium hydroxide, potassium hydroxide, hydrochloric acid, sulfuric acid, citric acid, boric acid, sodium dodecyl sulfate, hydrogen peroxide, and ethylenediaminetetraacetic acid (EDTA). These agents were tested in three different configurations: single step, double series, and quadruple series. The cleaning process was carried out at a pressure of 3 bar for a duration of 40 minutes. Among the tested configurations, the highest efficiency was achieved wit