FLOATING COVER

Abstract

A floating cover for covering a liquid storage comprises an inflatable bladder kept under continuous positive gas pressure. A preferred embodiment has a plurality of discrete inflatable bladder segments positioned on a common plane in abutting relation to form an inflatable bladder assembly. A gas communication conduit extends between the bladder segments for communication of positive gas pressure between the bladder segments.

Description

FIELD

There is described a floating cover that was developed to retain heat and prevent contaminants from getting into open topped storage tanks where liquids are stored. It is now appreciated that this floating cover has wider application to ponds and dugouts.

BACKGROUND

Canadian Patent No. 2,756,305 (Hindbo) entitled “Modular Enclosure System” describes a liquid storage tank that can be installed at a remote location and then removed to a new site when work is completed. There is a need for a cover to retain heat and exclude contaminants.

SUMMARY

There is provided a floating cover which consists of an inflatable bladder and an inflation assembly keeping the inflatable bladder under continuous positive gas pressure.

Although beneficial results may be obtained through the use of a unitary floating cover, the liquid storage tanks and ponds can be huge with surface areas 500 sq ft to 25,000 sq ft. With many installations, a unitary floating cover would not be practical. Even more beneficial results may, therefore, be obtained when the inflatable bladder comprises a plurality of discrete inflatable bladder segments positioned on a common plane in abutting relation to form a bladder assembly with a gas communication conduit extending between the bladder segments for communication of positive gas pressure between bladder segments.

The bladder segments can be arranged in a variety of configurations. It is preferred that the bladder segments are wedge-shaped. When the storage tank is round, this results in a circular pie configuration. However, the wedge-shaped segments will work equally well with square or rectangular configurations.

Liquid storage tanks vary in size. Therefore, it would be preferable if the basic system could be expanded, as required, to accommodate larger diameter storage tanks. Even more beneficial results may, therefore, be obtained by providing a plurality of inflatable bladder segments that form border around a perimeter of the basic configuration made with bladder segments that are wedge-shaped. With the circular pie configuration, the border is in the form of a ring.

The inflatable bladder segments forming the floating roof are exposed to various environmental influences, such as wind. It is, therefore, recommended that connectors be provided which connect abutting bladder segments.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to be in any way limiting, wherein:

FIG. 1 is a top plan view of a floating cover.

FIG. 2 is a top plan view of one of a plurality of wedge-shaped inflatable bladder segments that are joined to form a circular pie configuration of the floating cover of FIG. 1.

FIG. 3 is a top plan view of one of a plurality of inflatable bladder segments that are joined to form a ring around the circular pie configuration of the floating cover of FIG. 1.

FIG. 4 is a section view of the floating cover of FIG. 1, showing gas communication conduit detail as between abutting bladder segments.

FIG. 5 is a section view of the floating cover of FIG. 1, showing connector detail as between abutting bladder segments.

FIG. 6 is a section view of the floating cover of FIG. 1, showing internal structure and cabling.

FIG. 7 is a section view of the floating cover of FIG. 1, showing the detail of the internal structure shown in FIG. 6.

FIG. 8 is a section view of the floating cover of FIG. 1, showing interior detail of the interior baffle plate structure.

DETAILED DESCRIPTION

A floating cover generally identified by reference numeral 10, will now be described with reference to FIGS. 1-8.

Structure and Relationship of Parts:

Referring to FIG. 1, floating cover 10 is an inflatable bladder 12 kept under positive gas pressure by an inflation assembly 14. For ease of installation, inflatable bladder 12 consists of a plurality of discrete inflatable bladder segments, generally indicated by reference numeral 16, positioned on a common plane in abutting relation. This turns inflatable bladder 12 into a bladder assembly. Inflation assembly 14 can take a number of forms, such as an air pump, a blower or a fan.

There are two preferred configurations for bladder segments 16. Referring to FIG. 2, bladder segments 16A are wedge-shaped. Referring to FIG. 1, this enables bladder segments 16A to be arranged in a basic central configuration 18. Chosen for illustration is a circular pie for a basic central configuration 18 as this is the most common form of configuration. It will be appreciated that basic central configuration 18. Could also be illustrated as being square or rectangular. Referring to FIG. 3, bladder segments 16B form a portion of a border 20 that surrounds basic central configuration 18. Chosen for illustration is a ring for border 20 that surrounds basic circular pie configuration 18 and increases the area of coverage of floating cover 10.

Referring to FIG. 4, gas communication conduit 22 extends between bladder segments 16 for communication of positive gas pressure between bladder segments 16.

Referring to FIG. 7, connectors, generally identified by reference numeral 24, are provided which connect abutting bladder segments 16. The form of connector 24 chosen for illustration has a “D” portion 26 and a tie portion 28 which ties onto and engages “D” portion 26.

Referring to FIG. 8, internal detail is provided showing an upper bladder membrane 16U, a lower bladder membrane 16L and internal straps 30 that extend between upper bladder membrane 16U and lower bladder membrane 16L to keep upper bladder membrane 16U and lower bladder membrane 16L in constant relation, to avoid bladder 16 blowing up into a ball-like structure.

Operation:

Referring to FIG. 2, individual edge-shaped bladder segments 16A are floated upon the surface of liquid in a storage tank. Referring to FIG. 6, each of bladder segments 16A are connected using connectors 24 to form inflatable bladder assembly 12. Referring to FIG. 5, gas communication conduit 22 is connected between bladder segments 16A and then connected to inflation assembly 14 is used to inflate bladder segments 16A using positive gas pressure to form basic central configuration 18, which is shown as a pie configuration. Referring to FIG. 1, once inflated, inflatable bladder assembly completes floating cover 10.

With some installations, the diameter of the tank is larger than the diameter of circular pie configuration. Referring to FIG. 3, in such cases, individual bladder segments 16B are floated upon the surface of liquid in a storage tank. Referring to FIG. 5, each of bladder segments 16B are connected using connectors 24 to form inflatable bladder assembly 12. Referring to FIG. 5, gas communication conduit 22 is connected between bladder segments 16B and then connected to inflation assembly 14 for inflation using positive gas pressure to form border 20, which is shown as a ring 20. Referring to FIG. 1, once inflated border 20 increases the area of surface coverage of inflatable bladder assembly 12 to accommodate larger diameter liquid storage tanks

Although floating cover 10 will keep out contaminants, its primary purpose in most installations is heat retention. The circulating air fills an air space of approximately 14 inches in thickness. This air space provides a sufficient insulation value under most environmental conditions. If desired, warm air could be circulated. However, this is not viewed as being necessary.

In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.

The scope of the claims should not be limited by the illustrated embodiments set forth as examples, but should be given the broadest interpretation consistent with a purposive construction of the claims in view of the description as a whole.

Claims

1. A floating cover, comprising:

an inflatable bladder; and

an inflation assembly for keeping the inflatable bladder under continuous positive gas pressure.

2. The floating cover of claim 1, wherein the inflatable bladder comprises:

a plurality of discrete inflatable bladder segments positioned on a common plane in abutting relation to form a bladder assembly; and

a gas communication conduit extending between the bladder segments for communication of positive gas pressure between the bladder segments.

3. The floating cover of claim 2, wherein the bladder segments are wedge-shaped and are arranged in a basic central configuration.

4. The floating cover of claim 3, wherein the basic central configuration is a circular pie configuration.

5. The floating cover of claim 3, wherein at least one inflatable border made from bladder segments surrounds the basic central configuration.

6. The floating cover of claim 5, wherein the inflatable border forms a ring.

7. The floating cover of claim 2, wherein there are connectors that connect abutting bladder segments.

8. The floating cover of claim 1, wherein the inflatable bladder has an upper bladder membrane, a lower bladder membrane, and straps that extend between the upper bladder membrane and the lower bladder membrane to maintain them in constant spaced relation during inflation.