Abstract: A wastewater treatment apparatus for use in an offshore marine environment includes a vertically elongated vessel having upper and lower end portions, wherein at least half of the vessel is submerged during use. The vessel provides an interior for containing fluid during use and is attachable to an offshore marine structure such as a fixed platform or floating marine rig. An influent flow line adds produce wastewater to the interior of the vessel. An effluent is provided for discharging treated fluid from the vessel interior. The upper end portion of the vessel interior defines a free oil separation section, the lower end portion of the vessel interior defines a disposal caisson section. The middle section of the vessel interior defines an induced gas flotation section. A plurality of spargers are provided at the gas flotation section for emitting bubbles at multiple elevational positions within the middle section of the vessel interior.

Abstract: An apparatus for removing oil or gas from a wastewater flow stream includes a vessel having a vessel wall surrounding an interior. A flow inlet is provided for transmitting wastewater to be treated to the vessel interior. The vessel provides a primary oil outlet and a secondary oil outlet. An oil bucket receives floating oil for transfer to the primary oil outlet. A transversely positioned matrix of media extends across the cross section of the vessel interior to separate the vessel interior into first and second sections. The hydrocyclone separator carries a plurality of de-oiler hydrocyclone liners. The separator is positioned at least partially within and communicates with the vessel interior. The hydrocyclone separator is positioned upstream of the secondary oil outlet and downstream of the matrix of coalescing media. Oil separated by the hydrocyclone liners flows to the secondary oil outlet. Water separated by the hydrocyclone liners flows to the water outlet.

Abstract: Waste matter contained in a liquid is removed therefrom by introducing the liquid into a cell and introducing gas into the liquid to float waste matter to the liquid surface in the form of a floating scum. Gas nozzles situated adjacent the liquid surface are oriented to eject streams of pressurized gas across the liquid surface to blow scum into a waste outlet disposed adjacent the liquid surface. The nozzles are vertically adjustable to conform to different liquid surface levels.

Abstract: A complete system for removing oil from produced water and deck drain fluids in an offshore facility includes a surge settler which receives the produced water from a three-phase separator. In the surge settler, the produced water flows crosswise through a corrugated plate assembly to separate free oil and solids from the produced water. A portion of the produced water which is relatively free of solid particles (less than 50 microns) is then treated in a water washer with a portion which is relatively rich in solid particles further treated in a solids cleaner. In the water washer 90% or more oil droplets (less than 50 microns) is removed from the produced water and the relatively oil free water is then disposed by way of a skim pile. A portion of fluid from the water washer is further treated in a high efficiency skimmer.