Patent ID: 6461525
Filing Date: 2002-10-08
Classification: B01D

Abstract:
A method for removal of solids in a water treatment system having multiple filters, each filter comprising an air backwash system and a water backwash system, the method comprising:(a) closing influent valve and effluent valve of initial filter and opening backwash air valve of initial filter; (b) turning on backwash air blowers for air backwash, start air backwash of initial filter; (c) opening backwash water valve and dirty backwash water valve of initial filter; (d) turning on backwash pumps for water backwash, start air/water backwash; (e) backwashing initial filter with an air/water backwash; (f) closing influent and effluent valves of next filter, opening backwash air valve of next filter; (g) closing air backwash valve on initial filter to stop air backwash of the initial filter, start air backwash on next filter; (h) opening backwash water valve and dirty backwash water valve on next filter, begin air/water backwash of next filter while continuing to backwash initial filter with a water-only backwash; (i) closing backwash water valve and dirty backwash water valve of initial filter; (j) opening influent valve and effluent valve of initial filter; (k) repeat steps (f) to (j) with each filter to be backwashed; (l) turning off backwash air blowers for air backwash, closing backwash air valve on final filter; (m) turning off backwash pumps for water backwash and closing backwash water valve and dirty backwash water valve on final filter; (n) opening influent valve and effluent valve of final filter.