שאלה | At which frequency scale are physical cleaning backwash and chemical cleaning backwash of UF membranes required in membrane bioreactor systems?

At which frequency scale are physical cleaning backwash and chemical cleaning backwash of UF membranes required in membrane bioreactor systems?

		Scale of days/weeks for physical cleaning and scale of minutes for chemical cleaning
		Scale of days/weeks for physical cleaning and scale of years for chemical cleaning
		Usually only physical cleaning is required. Chemical cleaning should be avoided.
		Scale of minutes for physical cleaning and scale of days/weeks for chemical cleaning