Hydraulic and earth engineering – Fluid control – treatment – or containment – Fluid storage in earthen cavity
Patent
1986-05-16
1987-11-24
Scanlan, Jr., Richard J.
Hydraulic and earth engineering
Fluid control, treatment, or containment
Fluid storage in earthen cavity
405128, 405 53, B63G 500
Patent
active
047085231
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a method for constructing cavities in rock formations, and particularly, although not exclusively, vertical cylindrical cavities intended for storing in rock petroleum products, or other fluids, or solid products, such as chemicals, chemical waste, radioactive waste, and other materials which are suited for storage in rock cavities.
The object of the present invention is to provide such a method which will enable vertical cylindrical cavities to be constructed, blasted, in rock formations with the minimum explosive effect on residual cavity walls, while observing maximum safety conditions with respect to the working environment of the personnel involved in the construction of these cavities.
BACKGROUND PRIOR ART
It is previously known to store petroleum products, and also other liquids lighter than water, in a cavity formed in groundwater carrying rock formations, in which the stored liquid lies in direct contact with the water-permeable surface of the cavity walls. The pressure exerted on the cavity walls by the liquid stored in the cavity is lighter than the pressure exerted by surrounding groundwater, thereby counteracting any tendency of the stored liquid to pass through the wall.
When the stored liquid is lighter than water and insoluble therein, it is a normal practice to provide a water bed in the lowermost region of the cavity.
SE-A-7802027-8 and 7901278-7 describe and illustrate complexes for storing petroleum products and other fluids in rock formations. These storage complexes, or locations, have a very high storage capacity, despite being of relatively small horizontal extension. The stored product is therewith located within a concentrated area, and the expedient of shielding the storage area with a curtain of densely packed, waterfilled drill holes can therefore be more readily carried out, thereby to off-set lowering of the groundwater level and preventing the stored product from spreading to the complex surroundings.
According to these patent specifications, the cavities are located at substantially mutually equal depths, and when seen in horizontal section each cavity has a substantially circular or oval shape, and when seen in horizontal cross-section throughout the whole of the complex the mean points of the circular or oval horizontal sections of respective cavities lie in the corners of regular polygons, all having the same number of sides.
By regular polygon is meant a polygon in which all sides are of mutually equal length and all corner angles are the same. A regular polygon can thus be inscribed in a circle which passes through all of the corner points and the centre of which thus also forms the centre of the polygon.
In accordance with one embodiment of the invention these polygons have the form of various sized pentagons having a common centre point. The cavities are therefore arranged in concentric circles. A further cavity can be arranged so that its centre axis coincides with the centre point of these circles.
It is also known from SE-A-8300185-9 to construct in rock formations a fluid-storage cavity location in which the actual cavity has the form of a substantially vertical cylinder, around which there is provided a series of vertical holes forming a water-drainage shield; this drainage shield is intended for removal of the water bed upon which the stored fluid has rested.
Present day rock cavities for storing oil or petroleum products have the form of long "loaves", i.e. horizontally extending rock cavities presenting a bottom surface area of 500.times.25 m or thereabove, and a height of 30 m. It has been found that when storing oil products in rock cavities of this kind, in which the oil rests on a bed of water, microorganisms grow in the boundary layer between water and oil, the oil/oil products being destroyed thereby and rendered worthless for future use. When such cavities are used to store refined products, it has been found necessary to re-refine the products in order to guarantee their usefulness.
In order to over
REFERENCES:
patent: 1347934 (1920-07-01), Brown
patent: 3068654 (1962-12-01), Warren
patent: 3701262 (1972-10-01), Connell et al.
patent: 3925992 (1975-12-01), Backstrom
patent: 4363563 (1982-12-01), Hallenius et al.
patent: 4572707 (1986-02-01), Sagefors
Persson Per G.
Sagefors Karl I.
Boliden Aktiebolag
Knight Anthony
Scanlan, Jr. Richard J.
LandOfFree
Rock cavity does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Rock cavity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rock cavity will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2422207