GB2309940A

GB2309940A - Method and Apparatus for forming a dyke, dam or river bank from sludge

Info

Publication number: GB2309940A
Application number: GB9602423A
Authority: GB
Inventors: Po Tung Lim
Original assignee: LIM TUNG
Current assignee: LIM TUNG
Priority date: 1996-02-07
Filing date: 1996-02-07
Publication date: 1997-08-13
Also published as: GB9602423D0

Abstract

A method and apparatus for forming a dyke, dam or river bank from sludge, in which sludge/sedimentary material collected from the bed of a body of water is transferred into a container 7 and thereafter discharged into a carrier barge 6, the carrier barge 6 then being transferred to the required site where the material is discharged between walls 3 to form the desired dyke or river bank etc. As shown the sludge container 7 is borne by apparatus 5 comprising a structure 11 having a flat base section 12 and two downwardly extending legs 13 which define with the water surface a tunnel or corridor under the structure 11 adapted to receive a carrier barge 6. The apparatus 5 can be adapted to float on the water or sit on the bed.

Description

APPARATUS AND METHOD FOR SLUDGE AND SEDIMENT COIlECTIQN AND A DYKE FORMED THEREFROM The invention relates to apparatus and a method for sludge and sediment collection and a dyke formed therefrom, particularly for use in a river, canal, lake or other waterway.

Sludge and other sedimentary material which is found at the bottom of rivers and lakes can be used when dry, to provide a dyke or dam or "artificial" river bank for example to guide flowing water, to prevent sedimentation and silting up of waterways thus preventing navigation and flow, and to stop, waves and wash created by water traffic causing for example to guide flowing water, to prevent sedimentation and silting up of waterways thus preventing navigation and flow, and to stop bank erosion. Such artificial banks can be used to separate clean water from contaminated water, and to form artificial lakes. Artificial banks can be formed from a variety of materials such as from concrete, steel plates ete however the use of dried sludge and sediment is cheap, particularly because the material is "on site" already, is more environmentally friendly, providing a rich environment for plant growth and utilising an existing resource, and results in a more aesthetically appealing and natural effect.

It will be appreciated that as used herein the terms "dyke", "dam" or "bank" encompass a wide variety of forms of structure which all serve to channel and/or retain flowing or still water.

According to the invention there is provided apparatus for collecting sludge from a body of water, the apparatus comprising a containment part for storage of sludge, an outlet for discharging sludge from the containment part, and sludge collection means.

It is preferred that the apparatus is adapted to sit in, or on, a body of water, and that it comprises means adapted to receive a receptacle into which collected sludge is to be delivered. The means may comprise an area or bay beneath and defined by the apparatus. The area or bay may be defined by the base and two downwardly extending legs of the apparatus to define, with the surface of the water a tunnel open at two ends to allow entry and exit of a receptacle.

It is preferred that the outlet opens into the receptacle receiving means, for ease of delivery of sludge to the receptacle.

The containment part may comprise a vessel having a conical or V-shaped base, the apex of the cone or V including the outlet means. Collected sludge and sediment may thereby be easily delivered under force of gravity from the containment part to a receptacle.

It is preferred that the apex of the cone or V is disposed within the receptacle receiving means.

The collecting part may include overflow means disposed in a wall thereof to allow collected water to be drained off to avoid overflow. It is further preferred that one or both of the outlet and overflow means be provided with valve means to allow delivery of water or sludge therefrom to be controlled.

The sludge collection means may include suction means, and may include a longitudinally extending arm or boom at the end of which is a collecting head, adapted to reach down to the bed of the water to collect sludge and sediment.

The collecting head may incorporate cutting means, such as fork tines to disturb the bed and to aid in collection and to cut weed which may obstruct the function of the head.

The apparatus may be adapted to float on water.

According to a second aspect of the invention there is provided a sludge collection and delivery system comprising apparatus as hereinabove defined, and a receptacle for delivery of sludge to a point remote from the apparatus.

According to a third aspect of the invention there is provided a dam, dyke or river bank, comprising sludge collected by a sludge collection and delivery system as hereinabove defined.

The dam or bank may include retaining means to prevent loss of the sludge.

The retaining means may comprise one or more concrete partitions, substantially separating the sludge from the water.

According to a fourth aspect of the invention there is provided a method of forming a dam, dyke or river bank, comprising the steps of collecting sedimentary material from a bed of a body of water, transferring the sedimentary material to a carrier, transferring the carrier to a desired location and delivering the material to a site of dam, dyke or bank formation.

It is preferred that the step of transferring the sedimentary material to the carrier is accomplished under the force of gravity.

It is further preferred that the step of transferring the carrier to the said desired location is effected by the force of water flowing between the collection apparatus and site of dam, dyke or bank formation.

The invention will further be described by way of example with reference to the following drawings, in which: Figure 1 is a schematic transverse section through a dyke according to an embodiment of the invention; Figure 2 is a schematic end view of a first embodiment of a sludge collection and delivery system according to the invention; Figure 3 is an end view of a part of the sludge collection and delivery system of Figure 2; and Figure 4 is a schematic illustration of an alternative embodiment of sludge collection and delivery system according to the invention.

Referring to the drawings, and in particular Figure 1, there is illustrated a manmade dyke or river bank 1 comprising a layer of sludge and sediment 2, and two concrete walls or partitions 3 which are arranged parallel to one another with the sludge in between. The walls 3 may remain in place throughout the life of the dyke 1 or alternatively may be removed after the sludge 2 has dried.

Referring now to Figure 2 there is illustrated a system 4 for forming the dyke 1.

The system includes apparatus S for collecting sludge from a body of water and a receptacle 6 for removing the sludge to a point remote from the apparatus. As illustrated, the apparatus 5 consists of a container part 7 which, in the embodiment of Figure 2 is a longitudinally extended trough with a top which is open to the air and a V-shape (in section) base part 8. The apex of the base is provided with outlet means which may be a series of discrete apertures or a continuous slot forming an outlet 9. The outlet may be under the control of valve means of any suitable type as are known in the art. The container part 7 also includes an overflow pipe 10.

The container part 7 is borne upon a raft or pontoon 11 which consists of a substantially flat base section 12 through which the base of the container part projects. The base part 12 is supported by two downwardly extending legs 13 which are substantially parallel and extend the length of the base 12. Together, the base 12 and the legs 13 form an upturned "U", which defines with the water surface a tunnel or corridor beneath the apparatus 5. This tunnel or corridor is adapted to receive a receptacle, which in the illustrated embodiment is a boat or barge 14.

Figure 3 illustrates an alternative form of apparatus 5, which is intended to be of a larger scale than the apparatus of Figure 2. In this embodiment the apparatus 5 consists essentially of two container parts 7 of approximately the same configuration as the container of the first embodiment. The containers 7 are mounted at the sides of a central raft, or pontoon 11 shown schematically in this illustration. It will be appreciated that, in all embodiments, the precise configuration of the raft or pontoon 11 can be varied.

As will be appreciated, in all embodiments, the apparatus 5 further includes sludge collection means (not illustrated). A wide variety of such sludge collection means are known in the art of dredging, such as suction devices and archimedes screws and will not be described further here. It will be appreciated however that any suitable device can be used.

The boat or barge 14 can be of any conventional design. In the embodiment illustrated in Figure 3, the barge 14 is provided with two buoyancy devices 15 which in the embodiment are buoys which can be filled with air or water.

In use, the illustrated system can be used according to the method of the invention to form a man-made river bank or dyke 1 according to the invention as illustrated in Figure 1, in the following way. The apparatus 5 is positioned in a river, lake or canal where an artificial bank is required. It can be adapted to float on the water, or sit on the bed. The sludge collecting means is operated to collect sludge which is fed into the container part or parts 7. As water and sediment is transferred into the container part, the sediment falls to the bottom under the force of gravity and is guided downwardly towards the outlet 9 by the sloping walls of the V-shape bottom part. The water level rises in the container part until the overflow 10 is reached at which point the water is directed away from the apparatus 5 back into the main body of water under control of a valve (not shown). It will be appreciated that the apparatus 5 may be adapted to move under its own power, as for example by fitting a motor. When a sufficient quantity of sludge has been collected, a receptacle 6 or a number of receptacles are moved into the corridor under the apparatus 5. It should be noted that when the apparatus 5 is positioned in a flowing waterway, the receptacle 6 can be moved along the length of the corridor in the direction of the water flow by the water itself to save energy. When the receptacle 6 is in position, the valve 9 is opened and a quantity of sludge and sediment is delivered as required under the force of gravity. Thus again, energy is saved. The receptacle 6 is then moved to the point where the bank or dyke is under formation, again, preferably by the force of the flowing water, and is emptied. In one embodiment, emptying can be accomplished using the buoyancy devices 15. As will be appreciated, if one device 15 is flooded with water, that side of the receptacle 6 will become considerably heavier, causing that side of the receptacle 6 to sink lower into the water enabling the collected sludge to be easily emptied from it. The buoyancy device 15 on the opposite side prevents the receptacle 6 from sinking completely.

Once the sludge has been discharged, air can be introduced back into the flooded buoyancy device 15, and the receptacle 6 can be returned for further charging with sludge.

It will also be understood that there is a further advantageous and simple way to discharge sludge from the sludge carrier. As the density of sludge is heavier than water, the simple way of discharging the sludge is to topple the sludge carrier by pumping water into it.

After the sludge in the receptacle or receptacles has been emptied in the required place, the receptacles 6 become very much lighter. Thus, they can be easily moved back upstream to the apparatus by any suitable means, such as a steamer or other powered vessel. It is estimated that one small powered steamer can drag 50-100 receptacles at one time.

Claims

CLAIMS:

1. Apparatus for collecting sludge from a body of water, the apparatus comprising a containment part for storage of sludge, an outlet for discharging sludge from the containment part, and sludge collection means.

2. Apparatus according to claim 1, adapted to sit in or on a body of water.

3. Apparatus according to claim 1 or claim 2, including means adapted to receive a receptacle into which collected sludge is to be delivered.

4. Apparatus according to claim 3, wherein the means comprises an area or bay beneath and defined by the apparatus.

5. Apparatus according to claim 4, the area or bay being defined by the base and two downwardly extending legs of the apparatus to define a tunnel open at two ends.

6. Apparatus according to any of claims 3 to 5, wherein the outlet opens into the receptacle receiving means.

7. Apparatus according to any preceding claim, wherein the containment part comprises a vessel having a substantially conical or substantially V-shaped base.

8. Apparatus according to claim 7, the apex of the cone or "V" including the outlet means.

9. Apparatus according to claim 7 or claim 8, wherein the apex of the cone or "V" is disposed within the receptacle receiving means.

10. Apparatus according to any preceding claim, wherein the collecting part includes overflow means disposed in a wall thereof.

11. Apparatus according to claim 10, wherein the overflow means is provided with valve means.

12. Apparatus according to any preceding claim, wherein the outlet is provided with valve means.

13. Apparatus according to any preceding claim, wherein the sludge collection means includes a suction means.

14. Apparatus according to any preceding claim, wherein the sludge collection means includes a longitudinally extending arm or boom at one end of which is a collecting head, adapted to reach down to the bed of a body of water to collect sludge and sediment.

15. Apparatus according to claim 14, wherein the collecting head incorporates cutting means.

16. Apparatus according to claim 15, wherein the cutting means comprises fork tines.

17. A system for sludge collection and delivery including apparatus as set out in any of claims 1 to 16.

18. A dam, dyke or river bank comprising sludge collected by a sludge collection and delivery system according to claim 17.

19. A dam, dyke or river bank according to claim 18, including retaining means to prevent loss of sludge.

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20. A dam, dyke or river bank according to claim 19, wherein the retaining means comprises one or more concrete partitions substantially separating the sludge from the water.

21. A method for forming a dam, dyke or river bank, comprising the steps of - collecting sedimentary material from a bed of a body of water, transferring the sedimentary material to a carrier, transferring the carrier to a desired location and delivering the material to a site of dam, dyke or bank formation.

22. A method according to claim 21, wherein the step of transferring the sedimentary material to the carrier is accomplished by gravity.

23. A method according to claim 21 or 22, wherein the step of transferring the carrier to the said desired location is effected by the force of water flowing between the collection apparatus and site of dam, dyke or bank formation.

24. Apparatus substantially as hereinbefore described with reference to the accompanying drawings.

25. A system substantially as hereinbefore described with reference to the accompanying drawings.

26. A method substantially as hereinbefore described with reference to the accompanying drawings.