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AssigneeRobert Filter Manufacturing Company
InventorsCharles V. Roberts, William F. Sarra, Peter J. Neuspiel
Estimating the term…
A treatment facility has a granular media bed for use in acting upon (e.g. filtering) liquid mixtures, such as industrial and municipal water and wastewater, and employs a backwash operation between treatment operations for cleaning or otherwise enhancing the quality of the bed. A control system for the backwash operation establishes a first backwash rate for washing and scouring the granular media to release suspended solids and/or other impurities from the bed. Thereafter the control system establishes a second and generally greater rate for removing the released impurities from the facility. Preferably the first rate is chosen to just completely fluidize the granular bed, at which point a pressure responsive control system detects a constant differential pressure (i.e. a zero change in differential pressure), and the second rate, which generally is greater than the first rate, is responsive to the temperature of the backwash liquid.
A backwash control system for a treatment facility of the type having a granular media bed for use in treating liquid mixtures, such as industrial and municipal water and wastewater, said system including flow control means (54, 56) for establishing a first backwash flow rate at which a predetermine pressure condition exists across at least a part of the media bed, pressure detecting means (44) for sensing the predetermine pressure condition and means (58) responsive to the detection of said predetermine pressure condition for acting upon the flow control means to maintain said first backwash flow rate;
A method of backwashing a treatment facility of the type having a granular media bed for use in treating liquid mixtures, such as industrial and municipal water and wastewater, said method including the steps of:
A method of backwashing a treatment facility of the type having a granular media bed for use in treating liquid mixtures, such as industrial and municipal water and wastewater, said method including the steps of:
Dependencies are inferred from the claim text.