Abstract: A drinking water distribution reservoir has a new draft tube mixing arrangement. An intermediate opening in the draft tube enables water to flow between the central passage of the draft tube and an intermediate portion of the tank. Directional walls can be provided on the intermediate opening to help direct flow, and a check valve can be used to prevent flow from the intermediate section of the tank into the draft tube or prevent flow from the draft tube into the intermediate section of the tank. A venturi portion can also be provided on the draft tube to help draw water from the intermediate portion of the tank into the draft tube.

Abstract: A drinking water distribution reservoir has a new draft tube mixing arrangement. An intermediate opening in the draft tube enables water to flow between the central passage of the draft tube and an intermediate portion of the tank. Directional walls can be provided on the intermediate opening to help direct flow, and a check valve can be used to prevent flow from the intermediate section of the tank into the draft tube or prevent flow from the draft tube into the intermediate section of the tank. A venturi portion can also be provided on the draft tube to help draw water from the intermediate portion of the tank into the draft tube.

Abstract: A drinking water distribution reservoir has a new draft tube mixing arrangement. An intermediate opening in the draft tube enables water to flow between the central passage of the draft tube and an intermediate portion of the tank. Directional walls can provided on the intermediate opening to help direct flow, and a check valve can be used to prevent flow from the intermediate section of the tank into the draft tube or prevent flow from the draft tube into the intermediate section of the tank. A venturi portion can also be provided on the draft tube to help draw water from the intermediate portion of the tank into the draft tube.

Abstract: An upflow liquid clarifier for treating a liquid that contains dissolved or suspended solids has a lower chamber with two curved ends connected by a straight section, a centrally-disposed dividing wall extending upwardly from that lower chamber, and an outer wall that extends upwardly and outwardly from the lower chamber. Inlets in communication with the lower chamber provide entry for liquid, which rises in a helical motion through the clarifier. Motion of the water establishes a sludge blanket, through which clarified water rises and can be removed from near the top of the clarifier. A sludge removal structure allows the continuous or periodic removal of sludge.

Abstract: An upflow liquid clarifier for treating a liquid that contains dissolved or suspended solids has a lower chamber with an annular shape, an inner wall extending upwardly and inwardly from that lower chamber, and an outer wall that extends upwardly and outwardly from the lower chamber. Inlets in communication with the lower chamber provide entry for liquid, which rises in a helical motion through the clarifier. Motion of the water establishes a sludge blanket, through which clarified water rises and can be removed from near the top of the clarifier. A sludge removal structure allows the continuous or periodic removal of sludge.

Abstract: A method and apparatus are disclosed which provide enhanced solids-contacting vessel performance in which untreated liquid is injected into a lower portion of the vessel so as to flow in substantially helical and upward directions, solids separating from the untreated liquid into a suspended and rotating sludge blanket. The apparatus includes devices for withdrawing effluent from the vessel from a variety of locations depending upon the flow characteristics of the liquid in the vessel. The apparatus may include a radial weir trough that can be moved vertically within the vessel.

Abstract: In a drinking water reservoir, a draft tube is positioned above an inlet pipe to carry fresh water and water stored in a lower reservoir portion to an upper reservoir portion where the drinking water is mixed and stagnation of the reservoir contents is reduced. The draft tube can be used with a recycling pump and/or a mechanism for providing compressed gas to create a gas lifter to mix water in the lower storage portion with water in the upper storage portion when fresh water is not being added.

Abstract: Apparatus for discharging an additive into water in a treatment vessel comprises discharging means and means for feeding the additive to the discharging means. The discharging means may comprise a pipe, a nozzle, or a header conduit having a number of outlets. A method for discharging an additive into water in a treatment vessel includes the steps of adjusting the elevation of an outlet in a conduit relative to the treatment vessel and discharging the additive from the outlet in the conduit into water in the treatment vessel.

Abstract: A method and apparatus are disclosed which provide enhanced solids-contacting vessel performance in a vessel in which untreated liquid is injected into a lower portion of the vessel so as to flow in a substantially helical and upward direct to separate the solids from the liquid in a suspended, rotating sludge blanket. The vessel is equipped with an adjustable weir extending substantially radially form the vessel center to its peripheral wall for withdrawing effluent from the vessel from a variety of locations depending upon the flow velocity characteristics of the liquid in the vessel.