Liquid purification or separation – Processes – Making an insoluble substance or accreting suspended...
Reexamination Certificate
1999-06-22
2001-05-29
Lithgow, Thomas M. (Department: 1724)
Liquid purification or separation
Processes
Making an insoluble substance or accreting suspended...
C210S221200
Reexamination Certificate
active
06238569
ABSTRACT:
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
REFERENCE TO A “MICROFICHE APPENDIX”
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to wastewater treatment and particularly to an improved separator apparatus for separating oil from influent produced water, such as the wastewater generated from oil and gas well drilling and production operations. More particularly, the present invention relates to an improved flotation pile oil/water separation apparatus that includes an elongated, vertically supported flotation pile having an upper inlet end portion, a lower outlet end portion, and three zones for waste treatment including a free oil removal zone, an induced gas flotation zone, and a lower disposal zone.
2. General Background of the Invention
In the oil and gas well drilling industry, offshore platforms that are used in the drilling and production of oil and gas wells generate wastewater material that must be treated. This wastewater material is typically produced water that includes tiny droplets of oil. These droplets of oil must necessarily be removed from the waste stream before the treated water can be returned to the surrounding marine environment. Indeed, the oil must be removed sufficiently so that the water is clean enough to be discharged into the surrounding marine environment without adversely affecting marine plants and animals.
Patents have been issued that are directed to the concept of a flotation pile that is used to remove oil from sea water at an offshore oil platform. One example is U.S. Pat. No. 4,198,300.
Other patents that relate to the cleaning of produced water in the oil and gas well drilling and production environment include U.S. Pat. Nos. 4,252,649; 4,372,757; and 3,893,318.
BRIEF SUMMARY OF THE INVENTION
The apparatus of the present invention provides an improved wastewater treatment apparatus for use in a marine environment.
The present invention provides an improved wastewater treatment apparatus in the form of a flotation pile that combines many features in one vessel.
The present invention provides for solids cleaning and disposal and is adaptable to existing sump caissons.
The apparatus of the present invention can be used by fixed production facilities or floating production facilities and in either shallow or deep water applications.
The apparatus of the present invention can be used for produced water and open drain cleaning and disposal.
In the preferred embodiment, the apparatus includes an induced gas flotation section that includes multiple gas spargers positioned at differing elevational positions.
The apparatus includes a vertically elongated vessel having upper and lower end portions and an interior for containing fluid during use.
The apparatus of the present invention is preferably generally vertically oriented and placed in the surrounding marine environment so that little or no deck space is required for its operation.
Because the large majority of the vessel is under water during use, minimal platform weight is required. The apparatus of the present invention is a simple basic device that has no moving parts and therefore has low maintenance.
The vessel attaches to an offshore marine structure for example, at the boat deck portion thereof, a majority of the vessel being preferably submerged during use.
An influent flow line enables produced wastewater to be added to the interior of the vessel.
An effluent is provided for discharging fluid from the vessel interior.
The upper end portion of the vessel interior defines a free oil separation zone or section. The lower end portion of the vessel interior defines a disposal zone or section. The middle section of the vessel interior defines an induced gas flotation section.
A plurality of spargers are placed at differing elevational positions, each sparger emitting gas bubbles. The spargers are preferably placed within the middle (induced gas flotation) section of the vessel interior.
A plurality of inclined baffles can be positioned at respective multiple elevational positions within the middle section of the vessel interior. Oil removal flow lines are provided for removing oil from the upper section of the vessel interior.
A lower section of the vessel interior communicates with the discharge to discharge treated water from the vessel interior via a discharge flow line.
The discharge outlet can be an opening at the bottom of the vessel that communicates directly with the surrounding marine environment to discharge water after it has been sufficiently cleaned. The discharge outlet can also be a discharge pipe arrangement.
The spargers are positioned at preferably multiple (e.g. 3, 4) separate elevational positions.
The inclined baffles are positioned at differing elevational positions, one or two inclined baffles being preferably positioned next to of the spargers at a given level. The inclined baffles are preferably positioned in pairs at each different elevational position. Each pair of baffles at a given elevational position is circumferentially spaced (preferably ninety degrees) from the pair of baffles above it or below it.
When a discharge piping arrangement is used, the discharge outlet preferably communicates with an outlet flow line that extends to an elevational position near the fluid surface elevation inside the vessel interior in one embodiment.
REFERENCES:
patent: 2730190 (1956-01-01), Brown et al.
patent: 3893318 (1975-07-01), King, Jr. et al.
patent: 4173533 (1979-11-01), Williams
patent: 4198300 (1980-04-01), Williams
patent: 4252649 (1981-02-01), Favret, Jr.
patent: 4372757 (1983-02-01), Favret, Jr.
patent: 4428841 (1984-01-01), Favret, Jr.
patent: 4720341 (1988-01-01), Arnold
patent: 4927536 (1990-05-01), Worrell et al.
patent: 4948517 (1990-08-01), Young et al.
patent: 5078921 (1992-01-01), Zipperian
patent: 5543043 (1996-08-01), Bates et al.
patent: 5580463 (1996-12-01), Hubred
patent: 5584995 (1996-12-01), Meekel et al.
patent: 5897772 (1999-04-01), Chang et al.
He et al, “A Multiple—Loop Flotation Column for Wastewater Treatment” Separation Technology vol. 5, 1995 pp. 133-138, Mar. 1995.*
Finch and Dobby, “Column Flotation”, Copyright 1990, Published by Pergamon Press pp. 32-33, 1990.
Engineering Specialties, Inc.
Garvey, Smith, Nehrbass & Doody LLC
Lithgow Thomas M.
LandOfFree
Flotation pile oil/water separator apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Flotation pile oil/water separator apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flotation pile oil/water separator apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2557454