Cleaning a filtration membrane module comprising two plane membranes distant from one another and connected to sides of a framework, comprises mechanically cleaning the membrane, and chemically cleaning the membrane

摘要

The process of cleaning a filtration membrane module comprising two plane membranes distant from one another and connected to sides of a framework, comprises mechanically cleaning the membrane for 4 hours to 7 days, and chemically cleaning the membrane. The membranes define an internal space connected to a pipe (10) for flowing the filtrates, and an external space for collection of retentates. The mechanical cleaning step comprises injecting filtrates in the internal space via the pipe under pressure for 10 seconds to 10 minutes to attain a transmembrane pressure of 50 mbar. The process of cleaning a filtration membrane module comprising two plane membranes distant from one another and connected to sides of a framework, comprises mechanically cleaning the membrane for 4 hours to 7 days, and chemically cleaning the membrane. The membranes define an internal space connected to a pipe (10) for flowing the filtrates, and an external space for collection of retentates. The mechanical cleaning step comprises injecting filtrates in the internal space via the pipe under pressure for 10 seconds to 10 minutes to attain a transmembrane pressure of 50 mbar and to seal the pipe when the pressure is reached, and injecting a gaseous fluid to a base of a module for 1-120 minutes. The chemical cleaning is carried out by injecting a chemical reactant in the internal space. The method further comprises measuring an information representating the level of clogging of membranes, and comparing the information with a reference value. The chemical cleaning phase is performed when the information is higher than the reference value. The gaseous fluid is air.