Liquid purification or separation – Structural installation – Geographic
Reexamination Certificate
1995-11-13
2001-09-04
Upton, Christopher (Department: 1724)
Liquid purification or separation
Structural installation
Geographic
C210S220000, C261S077000, C261S094000
Reexamination Certificate
active
06284133
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Cross Reference to Related Applications
This application is related to Assignee's copending application Ser. No. 08/557,980 filed Nov. 13, 1995.
2. Field of the Invention
Bioremediation of dissolved hydrocarbons in ground water by increasing the amount of dissolved oxygen in the ground water resulting in enhanced biodegradation by aerobic microbes.
3. Background Art
U.S. Pat. No. 4,950,394 to Bernhardt et al relates to an arrangement for driving out volatile impurities from the ground water and from ground through which it flows. More particularly, it relates to the arrangement in which the driving out is performed by producing a negative pressure in a well shaft extending to the region of the contaminated ground water and supplying a gas, especially fresh air, underneath the water level of the well shaft. The limiting wall of the well shaft is provided, at least in the region between the air inlet and the water table, with a plurality of fine capillary openings which produce a laminar liquid flow with relatively high speed, and a greater free throughflow or passage surface than in a remaining region of the limiting wall of the well shaft.
In U.S. Pat. No. 5,332,333 to Bentley, volatile contaminants are removed from the vadose zone of contaminated earth by vacuum extraction through a borehole placed into the contaminated area. Means are provided for substantially trapping water within the extraction borehole so as to prevent contaminated water from being brought to the surface. Means are also provided for maintaining substantially atmospheric pressure at the bottom of the extraction borehole so as to prevent water from the water table from rising into the borehole and to allow improved circulation of air through the contaminated zone. Preferably the conduit is kept open and pressure is maintained by passive infiltration of atmospheric air into the bottom of the conduit but, if desired, air may be injected into the conduit by positive pressure means.
U.S. Pat. No. 5,358,357 to Mancini et al discloses a process and apparatus for high vacuum groundwater extraction in which the gas inlet is generally situated at a level below the natural water table but above the level to which the groundwater drops after the pumping process has been in operation for a period of time.
SUMMARY OF THE INVENTION
In typical hydrocarbon-contaminated ground water, the level of dissolved oxygen is low due to the high biological oxygen demand. The present invention increases dissolved oxygen levels in the ground water thereby increasing biological activity. The increased biological activity means that more of the dissolved hydrocarbons will be consumed at a greater rate. The instant process and apparatus for remediating dissolved hydrocarbon in ground water involves drawing ambient air down through a tubing and aeration stone into ground water by the vacuum created by a soil vapor extraction (SVE) system thereby increasing the amount of dissolved oxygen in the SVE well and in the ground water resulting in enhanced biodegradation by aerobic microbes.
REFERENCES:
patent: 2744065 (1956-05-01), Lacey
patent: 3846290 (1974-11-01), Raymond
patent: 4872994 (1989-10-01), Jakob
patent: 4943305 (1990-07-01), Bernhardt
patent: 4950394 (1990-08-01), Bernhardt et al.
patent: 5080805 (1992-01-01), Houser
patent: 5221159 (1993-06-01), Billings et al.
patent: 5277518 (1994-01-01), Billings et al.
patent: 5332333 (1994-07-01), Bentley
patent: 5358357 (1994-10-01), Mancini et al.
patent: 5474685 (1995-12-01), Breslin
patent: 0 328 993 B1 (1989-08-01), None
Bealer, Jr. Leroy J.
Schaefer William L.
Shell Oil Company
Upton Christopher
LandOfFree
Bio aerator does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Bio aerator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bio aerator will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2438027