There is disclosed herein equipment and methods for screening and concentrating wastewater overflow from combined sewer systems and the like. Exemplary equipment includes a separator employing a substantially cylindrical rotating screen. Influent is piped upwardly into the equipment and deflected outwardly by plural distributors toward the inner surface of the screen in a manner to achieve a desired flow rate and flow pattern of the influent onto the screen. Means including the distributors are provided for controlling the flow rate and for suitably directing the influent in a plurality of substantially discrete inclined streams toward the inner surface of the rotating screen. The screen is rotated at a speed to achieve a desired centrifugal force. Effluent passes through the screen to an outlet and the remaining concentrate passes to an outlet. The screen is in the form of a screen cage having a plurality of removable screen panels for facilitating replacement of damaged screens or changing screen type or mesh size. Cleaning means is provided for directing a cleaning fluid periodically at the screen. The methods disclosed involve the manner in which the influent, effluent, concentrate and backsplash are handled, and the manner in which the influent is screened to achieve a fluid concentrate which may be pumpable to other treatment equipment for ultimate disposal.
CROSS REFERENCE TO RELATED APPLICATIONS
The concepts disclosed herein are directly related to those disclosed in applicant's co-pending application Ser. No. 42,165 (now abandoned in favor of Ser. No. 211,763, filed Dec. 23, 1971) entitled "IMPROVED WASTEWATER CONCENTRATION" filed June 1, 1970, of which the present application is a continuation-in-part, the disclosure of which is incorporated herein by reference. This co-pending application discloses a wastewater concentrator constructed and operated similar to that disclosed herein; however, the present wastewater concentrator with plural distributors is an improvement thereover.
The concepts disclosed herein also are related to those disclosed in U.S. Pat. No. 3,539,008 entitled "SCREENING APPARATUS EMPLOYING ROTATING CYLINDRICAL SCREEN AND STATIONARY FEED MEANS," and U.S. Pat. No. 3,511,373, both of which are assigned to the assignee of the present application and the disclosures of which are incorporated herein by reference. Briefly, said U.S. Pat. No. 3,539,008 discloses apparatus involving a rotating substantially cylindrical screen in combination with a stationary distribution means for screening an influent. The screen and distribution means may be used in combination with a downstream planar vibratory separator for further screening of the concentrate from the rotating screen. Said U.S. Pat. No. 3,511,373 discloses apparatus similar to that of the foregoing patent and is directed to means for facilitating cleaning of said rotating screen. Reference is also made to related applications, filed concurrently herewith, Ser. No. 42,098, now abandoned, entitled "UP-FLOW SEPARATOR," filed in the name of Theodore R. Westfall; Ser. No. 42,099, now abandoned, entitled "IMPROVED ROTATING SCREEN SEPARATOR," filed in the name of Philip H. Mook; and Ser. No. 42,100, now U.S. Pat. No. 3,627,130, entitled "WASTEWATER CONCENTRATION," filed in the names of Walter J. Talley, Jr. and Howard W. Wright, Jr. These applications contain a similar disclosure to that set forth in said application Ser. No. 42,165, now abandoned, but include claims directed to various of the structural and operational features disclosed therein.
A centrifugal hydroextractor for fibrous material processing, comprising a rotating basket and a dispensing member for the material to be processed, which is rotatably mounted coaxially with and internally of said basket. The dispensing member is provided with material guide paths from the center to the side walls of the basket; at least one disc valve, closing the basket at the top, is fast with said dispenser and has a central aperture for the material supply and a number of peripheral ports corresponding to said paths. Drive means provided for rotating said basket and dispensing member with different angular velocities.
A method of feeding material for centrifugation to a continuously operating centrifuge having a conical drum, wherein the stream of material for centrifugation to be fed to the drum is divided up into n sub-flows and the n sub-flows are fed to n axially consecutive annular sections of the drum surface, the sizes of the sub-flows fed to the annular sections per unit of length in the axial direction being in the same ratio as the squares of the average diameters of said annular sections and a centrifuge with a distributor system inside the drum for dividing the material into n sub-flows.
A liquid-solids separator, or centrifuge, of the type having a screw conveyor is provided with a series of offset conveyor flights. A spacer is positioned within the offset of the conveyor flights to form a channel therein. Rinse liquid is introduced into the channel through the central hub of the conveyor. The channel directs the rinse liquid into the heavy phase cake. An opening may be provided at various radial distances for varying the position of introduction of the rinse liquid from the channel. The amount of rinse liquid introduced through various channels formed by the series of offset conveyor flights may also be varied.
