CA1259635A - Diluvial diving dredge - Google Patents
Diluvial diving dredgeInfo
- Publication number
- CA1259635A CA1259635A CA000553591A CA553591A CA1259635A CA 1259635 A CA1259635 A CA 1259635A CA 000553591 A CA000553591 A CA 000553591A CA 553591 A CA553591 A CA 553591A CA 1259635 A CA1259635 A CA 1259635A
- Authority
- CA
- Canada
- Prior art keywords
- recovery unit
- boom
- removal
- separating
- water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F7/00—Equipment for conveying or separating excavated material
- E02F7/02—Conveying equipment mounted on a dredger
- E02F7/023—Conveying equipment mounted on a dredger mounted on a floating dredger
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/08—Dredgers; Soil-shifting machines mechanically-driven with digging elements on an endless chain
- E02F3/081—Dredgers; Soil-shifting machines mechanically-driven with digging elements on an endless chain mounted on floating substructures
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F5/00—Dredgers or soil-shifting machines for special purposes
- E02F5/28—Dredgers or soil-shifting machines for special purposes for cleaning watercourses or other ways
- E02F5/282—Dredgers or soil-shifting machines for special purposes for cleaning watercourses or other ways with rotating cutting or digging tools
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F7/00—Equipment for conveying or separating excavated material
- E02F7/005—Equipment for conveying or separating excavated material conveying material from the underwater bottom
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Mechanical Engineering (AREA)
- Ship Loading And Unloading (AREA)
Abstract
ABSTACT
A dredging method and apparatus is disclosed for the recovery of material from below the beds of rivers and other bodies of water. The apparatus comprises a recovery unit, having upper and lower booms, which is movably supported on a platform and means for raising and lowering the recovery unit.
The lower boom has material digging and removal means attached to an endless conveyor and the upper boom has material separating means and means for removal of the separated material. The apparatus also includes means for washing and separating the material removed by the removal means of the lower boom. The method for moving the apparatus includes the steps of washing and separating the material removed by the lower boom on the dredging apparatus, separating the material which caves in on the upper boom in situ and removing the material separated from the caved-in material to the surface for collection on the dredging apparatus.
A dredging method and apparatus is disclosed for the recovery of material from below the beds of rivers and other bodies of water. The apparatus comprises a recovery unit, having upper and lower booms, which is movably supported on a platform and means for raising and lowering the recovery unit.
The lower boom has material digging and removal means attached to an endless conveyor and the upper boom has material separating means and means for removal of the separated material. The apparatus also includes means for washing and separating the material removed by the removal means of the lower boom. The method for moving the apparatus includes the steps of washing and separating the material removed by the lower boom on the dredging apparatus, separating the material which caves in on the upper boom in situ and removing the material separated from the caved-in material to the surface for collection on the dredging apparatus.
Description
~2~i~63~
This invention relates generally to dredges and more particularly to a diluvial dredging apparatus for removing material from below the beds of rivers and other bodies of water.
BACKGROUND OF TH~ INVENTION
Placer gravels containing precious metals such as gold are found in both the alluvial gravels on the surface of riverbeds and in the diluvial gravels beneath the beds of rivers. In the past, there have been many different types of dredging apparatus used for dredging placer gravels in order to recover gold and other precious metals. These dredges have used endless conveyors with buckets attached thereto and suction-type apparatus for bringing the material to the surface for final separation and further processing. These dredges can generally remove the material on the surface of the riverbeds, the alluvial gravels, but they cannot penetrate the actual riverbed containing the more compacted and rocky diluvial gravel. This is a problem now, as much o~ the alluvial sands have been depleted oE precious material and there is a need to access new metal and ore containing sites such as the diluvial gravels.
The present invention overcomes this problem by providing a dredging apparatus capable of digging into the river bed and penetrating and collecting the diluvial gravels containing the precious metals.
SUMMARY OF INVENTION
Broadly, the present invention provides a recovery unit for use in a dredging apparatus which comprises a lower primary boom and an upper secondary boom. The primary boom has rn/kh L2~635 an endless conveyor with material digging and removal means attached thereto. The secondary boom has material separating means and means for removal of the separated material. The recovery unit also includes means for longitudinally moving the two booms relative to one another.
The present invention also provides a dredging apparatus for the recovery of material from below the beds of rivers and other bodies of water. This apparatus comprises the above-described recovery unit which is movably supported on a platform and includes means for raising and lowering the recovery unit. Means are also provided for washing and separating the material removed by the removal means of the primary boom.
The present invention also provides for a method for dredging material from below the beds of rivers and other bodies of water utilizing a dredging apparatus having a primary and secondary boom recovery unit. This method includes the steps of washing and separating the material retrieved by the primary boom on the dredging apparatus whereby the material fines are collected, the washed material is discarded, and the wash water is returned to the body of water with minimal silt disturbance.
The method further includes the steps of separating material ln situ which caves in on the secondary boom and removing the fines separated from the caved-in material to the surface for collection on the dredging apparatus.
BRIEF D~;:SCRIPTION OF THE DRAWINGS
A specific embodiment of the invention is described in further detail with reference to the drawings in which:
FIGURE 1 is a side view of an embodiment of the invention in situ;
rn/kh ~2S~63~i -FIGURE 2a is a cross-section of the recovery unit and FIGURE 2b is an end-view of the unit;
FIGURE 3 is a perspective view of the lower end of the recovery unit showing the primary boom in greater detail;
FIGURE 4 is a schematic drawing of the fines removal system of the secondary boom;
FIGURE 5 is an end-on view of an embodiment of the invention with the recovery unit in a horizontal position, detailing the support structure for the recovery unit;
FIGURE 6 is a schematic drawing of the side view of the recovery unit when in the horizontal position, detailing the structure of its upper end; and FIGURE 7 is a pictorial representa~ion of an embodiment of the invention in operation.
DETAILED DESCRIPTION
. _ ... .
Referring to FIG. 1, the dredging apparatus of the preferred embodiment is shown to basically comprise a floating platform 1, such as two barges combined in a manner similar to a catamaran (see FIG. 5), which supports a recovery unit 22 by means of a mast 5. The platform 1 also supports a wash area 3 at the stern and a hoist 23 which is centrally located. A wash water return hose G leads from wash area 3 to the recovery unit 22. Various storage areas and operation control stations are also present on platform 1 but are not specifically shown in the drawing; ~he platform has an anchor line 2 which is connected to a winch (not shown) on the shore.
rn/kh : ~ --r~ . ' A, , ,.~
ss63s Details of the recovery unit 22 are shown in FIGS. 2 to 4 and 6. The recovery unit 22 includes an upper boom 7 and a lower boom 8. These booms are slidably movable with respect to one another along their longitudinal axes by means of long stroke hydraullc cylinders 4 (see FIGS. 1 and 6), attached at the up~er end and on each side of the recovery unit 22. As shown in FIG. 6, the hydraulic cylinders 4 are attached to the upper and lower booms 7, 8 in an angled manner. Clips 9 are located along the length of both sides of the recovery unit 22 and attach the lower corners of the upper boom 7 and the upper corners of the lower boom 8 together in such a way that the booms are movable with respect to each other along their longitudinal axes only. The clips ~ prevent the booms rom separating from one another and moving independently.
Referring now to FIGS. 2a, 2b and 3, the lower boom 8 includes a support structure for an endless conveyor made up of two parallel loops of connected links 12 which are supported on parallel pairs of transverse rollers 13 at the lower end and parallel pairs of transverse rollers 35 at the upper end.
Although not specifically shown, transverse rollers ara also located in a spaced manner along the length of the lower boom 8 in order to support the connected links 12 in an even manner.
Each pair of rollers rotates on a cylindrical roller shaft 10 which is connected to the support structure of the lower boom in such a way that the shaft 10 can rotate on its longitudinal axis while supporting the rollers and other components of the conveyor. Buckets 11 are attached at each end thereo~ to the loops of connected links 12. The buckets 12, therefore, rn/kh ..
- 12~9635 maintain a constant distance between the loops of connected links 12 and keep the links 12 on the rollers 13 and 35. Rakes (not shown) may be interspersed between the buckets 11 and attached to the loops of connected links 12 in a similar manner as the buckets 11. Such rakes may aid in the filling of the buckets or may help prevent the buckets 11 from catching on boulders or bedrock during operation. The wash water re-turn hose 6 channels water from the wash area 3 into the lower boom 8. The water then follows the downward path of the buckets to the area being worked.
Details of the structure of the upper boom 7 will be described with reference to FIGS. 2a, 2b and 4. As can be seen in FIG 2a, upper boom 7 consists of a hollow ballast chamber 19 having a substantially rectangular cross-section upon which is attached a sluice separator 18, each having distinct functions.
The sluice separator 18 extends from the lower end of the upper boom 7 up to the point along the lower boom 8 which is at the deck level of the floating platform 1. Both sluice separator 18 and ballast chamber 19 are covered by a rectangular shaped solid end cap 17 (FIG. 2b). Means for filling and emptying ballast chamber 19 are located on deck. These means are not shown in the figures but can include pumps and hoses Gr other similar standard equipment available to those skilled in the art.
The sluice separator 18 includes a transversely and longitudinally extending grating 14, a transversely and longitudinally extending fine-mesh screen 15, a fines chamber 2 rnfkh and a pipe system 20, 21 including a venturi nozzle 16 [see FIG.
4]. The grating 14 includes transversely extending parallel bars which prevent large pieces of material from damaging the fine-mesh screen 15 which is located a short distance beneath it. The mesh size of the fine-mesh screen 15 will depend on the size of the particles that are to be collected. ~lternatively, several different screens can be used in the sluice separator, placed one above another and ranging from a coarse mesh on top to a fine meshed screen on the bottom. In this manner, only the very fine material will be in contact with the fine screen, thus preventing damage to the screen by large objects that would normally pass through the grating 14.
The fines chamber 24 has a rectangular cross section, its upper surface being the fine-mesh screen 15. Within fines chamber 24 is the pipe system 20, 21. A pipeline 20 o~ circular cross section extends from deck level to the lower end of the upper boom 7 along a bottom corner of the fines chamber 24. At the lower end, pipeline 20 has a right angle bend to a short section running parallel to the end cap 17 and ends with a venturi nozzle 16. The venturi 16 has a frustoconical portion ending with a cylindrical portion of lesser cross sectional area than that of pipeline 20, thereby causing the velocity o~ the fluid being transported through pipeline 20 to be increased when exiting the nozzle.
Pipeline 21 is of similar configuration to that of pipeline 20, however, it extends from deck level to the lower end of the upper boom 7 along the opposite bottom corner of fines chamber 24. The pipeline 21 does not have a venturi rn/kh ~L~5~363S
, nozzle at its end. In order to create a negative pressure in the fines chamber 24 so that the ~ines will be transported to the deck through pipeline 21, the venturi 16 of pipeline 20 is inserted into the opening of pipeline 21. The circumferential gap ~see FIGS. 2a and 4] that occurs between the outer perimeter of the venturi 16 and the inner perimeter o~ pipeline 21 aiiows material to flow through it and into pipeline 21.
Means for pumping a 1uid through pipeline 20 are located on the deck of the platform 1, but are not specifically shown in the figures. Also on the deck but not shown are collection means for the fines that are brought to the surface through pipeline 21.
The recovery unit 22 is supported by a mast 5 which is further supported by the support structure 29. The support structure 29 and the means of attachment of the recovery unit 22 and mast 5 to it are presented in FIG. 5. FIG. 5 depicts the support structure 29 as a framework located on and supported by the floating platform 1. Cylindrical shafts 25 which are used to pivot the recovery unit 22 during operation are rotatably supported on either side of the recovery unit 22 by pillow blocks 26 having bushings through which shafts 25 pass. In the embodiment shown in FIG. 5, there are four pillow blocks 26 which are bolted to the support structure 29 supporting the shafts 25 proximally and distally to recovery unit 22.
Attached to the proximal end of each shaft 25 is a cylindrical roller 28. Each roller 28 rests between guides 27 defined by vertically spaced elongated sections of angle irons.
These guides 27 (see also FIG. 6) are attached to the lower rn/kh ~;~5963~i;.
boom 8 in such a way that the pivot point of the recovery unit 22 is slightly below the level of roller shafts 10 o~ the lower boom 8.
The mast 5 (not shown in FIG. 5) is attached to support structure 29 at pivot~ble attachment points 30. In this embodiment of the invention, attachment points 30 are attached to the support structure 29 at four points, two on either side of recovery unit 22. The mast 5 moves with the recovery unit 22 at all times.
In FIG. 6, the upper end of the recovery unit 22 is depicted at A and the part of the unit that is at and just below deck level when the unit is submerged is depicted at B. The side view o~ the recovery unit 22 shows in general, the upper and lower booms 7, 8, connecting clips 9 and buckets 11. The sluice separator 18 is shown at B to end at deck level. Guides 27 are attached to lower boom 8.
At A, buckets 11 empty their contents into hopper 31, rotate over rollers 35 and are then trànsported within the lower boom 8 to the lower end of the recovery unit 22. Rollers 35 at the upper end of lower boom 8 are the only pair of rollers in the endless conveyor which have a drive mechanism connected thereto (not shown). This mechanism rotates rollers 35 and causes the endless conveyor to move. The hopper 31 has t~o side panels located on either side of the recovery unit 22 which attach to the mas~ 5 above the recovery unit 22 at pivot point 36~ The hopper 31 is pivotable so tha~ it can remain vertical when the recovery unit and mast are at different angular positions during operation. The hopper 31 is shaped like a rn/kh ~2~96~i large funnel. Its lower tube-like portion is directed into the wash area 3 (see FIG. 1).
The hydraulic cylinders 4 are connected to a standard hydraulic pump and control system ~not shown) which is located on the deck of the floating platform 1.
The recovery unit 22 is connected to mast 5 by means of a lug 34, cable 33 and pulley 32. The lug 34 is attached to the upper end of the lower boom 8 and the pulley 32 is located at the upper end of the mast. Cable 33 is connected at deck level to hoist 23. A multiple pulley system could also be used in order to reduce the amount of work required to move the boom. Note that the recovery unit 22 is generally raised to float on the water and lowered into the water by emptying or filling the ballast chamber 19 of the upper boom 7 with water.
When the recovery unit 22 is to be raised from the floating position to a horizontal position above the water level, hoist 23 and pulley 32 are utilized.
The operation of the dredging apparatus as it i5 used when practicing the preferred method of the invention will now be described.
The preferred embodiment of the invention provides a dredging apparatus for use in rivers or other bodies of water for material removal and separation of diluvial material taken from below the riverbed. In particular, this apparatus is designed for use in placer gold recovery operations.
Firstly, the floating platform 1 is moved to the desired location in the river and is anchored to the shore by means of the anchor line 2 (see FIGS. 1 and 7) which is attached _g_ rn/kh 125~3~;
on the shore to a winch. The recovery unit 22 is in an almost horizontal position floating on the water, the ballast chamber 19 filled with air.
Once the platform 1 is positioned, dredging is commenced. In order to lower the recovery unit into the water, the ballast chamber 19 is flooded with water. The recovery unit 22 pivots about the rollers 28 between the guides 27. Depending on the conditions of the material being dredged, weighted mud may be used with water in the ballast chamber 19 to provide more weight to the recovery unit.
When the end of the recovery unit 22 hits the riverbed, the operation of the endless conveyor is begun. The buckets 11 on the endless conveyor dig into the riverbed while removing material to the surface. The filled buckets 11 empty their contents into the hopper 31 tFIG. 6) and then travel over rollers 35 and back through the inner portion of the lower boom 8.
As the buckets 11 dig a channel into the riverbed, material on either side of the channel may cave in onto the grating 14 of the upper boom 7 ~FIG. 2a]. The material which passes through the grating 14 falls onto the fine-mesh screen 15 which separates the fines from the coarser material. The fines which pass through ~he fine-mesh screen into the fines chamber 24 settle toward the lower end o~ the upper boom 7 due to gravity and negative pressure. The negative pressure is caused - by pressurized air flowing from pipeline 20 through the venturi nozzle 16 at an increased velocity and into pipeline 21. The negative pressure draws the water containing the fines through rn/kh ~2S~6~
the circumferential gap bet~een the venturi 16 and opening of pipeline 21 and into pipeline 21 through which it is transported to the deck where it is collected. The collection means may simply be storage tanks where the fines and water are kept until they are removed to the shore for final settling and separation. Alternatively, settling tanks or hydrocyclones may be present on deck to effect final separation in situ.
As previously mentioned, the material recovered by the buckets 11 of the lower boom is emptied into the hopper 31. The hopper 31 feeds the material into the wash area 3 located on the deck of the plat~orm 1 for washing and separation. The wash area can comprise a sluice separator which separates the large pieces of gravel or rock from the fines. The washed gravel and rocks are disposed of overboard into an area that is not to be dredged or has already been dredged. The fines are collected for storage prior to final separation and processing on shore.
The cleaned wash water is returned through the hose 6 to the river. In order to prevent a large amount of silt disturbance from occurring, thç wash water is returned through the hose 6 into the lower boom 8 where it follows the downward path of the buckets ll.
When the recovery unit has dug down to the desired depth in the riverbed, the entire dredging apparatus is gradually moved by means of the anchor-line 2 and winch towards the shore as shown in FIG. 7. As can be seen in FIG. 7 r dredging has just begun at position A and the recovery unit 22 has reached the desired depth in the riverbed. As the winch pulls the apparatus toward the shore, the buckets ll of the rn/kh 1259~
endless conve~or dig into the riverbed and recover more material. If the recovery unit 22 encounters a boulder which is too large to be dug out (as seen between positions A and B), the lower and upper booms, 8 and 7, are moved relative to one another by means of the hydraulic cylinders 4 so that they "walk" over the boulder. The buckets 11 of the endless conveyor continue to remove material as the unit moves over the boulder and back down to the desired depth. Between positions B and C, the recovery unit 22 is shown to be removing material from just above the bedrock. At position ~ the dredging apparatus has almost reached the shore and dredging the channel is completed.
The recovery unit is then "walked" out of the channel that has been dug. The water in the ballast chamber 19 is pumped out so that the recovery unit 22 rises to float on the surface of the river. The dredging apparatus can then be moved back to position A to repeat the dredging method a short distance away and parallel to the location previously dredged.
An important feature of the dredging apparatus of the preferred embodiment is that the recovery unit 22 is pivotably raised and lowered passively in the water by means of the ballast chamber 19 being filled with air or water. The hoist 23 is only used when the recovery unit 22 is to be raised out of the water into the horizontal position. This is done when repairs and maintenance to the recovery unit 22 are being performed, or when the dredging apparatus is to travel long distances in the water.
The preferred embodiment has been described utilizing a floating platform 1. Alternatively, the platform could be rn/kh ~L2~63~;i based on land, depending on the location to be dredged. The land based platform could be mounted for example, on tracks, wheels or a skid. The platform could still be moved by means of a winch and anchor-line 2.
In the preferred embodiment end cap 17 completely covers both the sluice separator 18 and ballast chamber 19.
Alternatively, the end cap 17 may completely cover the ballast chamber 19 and fines chamber 24 while having a grating having transversely extending parallel bars extending across the area between grating 14 and fine-mesh screen 15. In this way, material passing through gxating 14 but too large to pass through the fine-mesh screen 15 will be able to pass through the grating o end cap 17 thereby preventing the area between grating 14 and fine-mesh screen 15 from getting clogged.
The preferred embodiment of the apparatus has been described using specific components. It will be readily apparent to those skilled in the art that many types of standard, readily available components can be used to construct the dredging apparatus. For example, the hydraulic cylinders ~
used to move the upper and lower booms, 7 and 8, relative to one another can be replaced by a pulley or rack and pinion arrangement. The buckets 11 can also be of various shapes depending on the type and the conditions of the material that is to be dredged. Different shaped buckets can be alternated on the conveyor so that the material can be more efficientl~
loosened and remoYed. As previously mentioned, rakes can also be interspersed with the buckets in order to loosen the material. There are many ways in which the buckets and conveyor rn/kh ~L25963~
can be assembled in order that the material being dredged easily falls into hopper 31. The material can fall into the hopp~r by means of gravity, or high pressure water jets may be used to empty out the buckets. Although not shown in the drawings, the upper end o~ the endless conveyor may also be altered so that the conveyor makes an angle downward over additional rollers 35 so that the openings o~ the buckets 11 are inverted downward and the material held therein is emptied into the hopper 31.
Further alterations and variations to the apparatus will be readily apparent to those skilled in the art, therefors the scope of protection to the present invention is not intended to be limited by the above described embodiments, but solely by the claims attached hereto.
rn/kh
This invention relates generally to dredges and more particularly to a diluvial dredging apparatus for removing material from below the beds of rivers and other bodies of water.
BACKGROUND OF TH~ INVENTION
Placer gravels containing precious metals such as gold are found in both the alluvial gravels on the surface of riverbeds and in the diluvial gravels beneath the beds of rivers. In the past, there have been many different types of dredging apparatus used for dredging placer gravels in order to recover gold and other precious metals. These dredges have used endless conveyors with buckets attached thereto and suction-type apparatus for bringing the material to the surface for final separation and further processing. These dredges can generally remove the material on the surface of the riverbeds, the alluvial gravels, but they cannot penetrate the actual riverbed containing the more compacted and rocky diluvial gravel. This is a problem now, as much o~ the alluvial sands have been depleted oE precious material and there is a need to access new metal and ore containing sites such as the diluvial gravels.
The present invention overcomes this problem by providing a dredging apparatus capable of digging into the river bed and penetrating and collecting the diluvial gravels containing the precious metals.
SUMMARY OF INVENTION
Broadly, the present invention provides a recovery unit for use in a dredging apparatus which comprises a lower primary boom and an upper secondary boom. The primary boom has rn/kh L2~635 an endless conveyor with material digging and removal means attached thereto. The secondary boom has material separating means and means for removal of the separated material. The recovery unit also includes means for longitudinally moving the two booms relative to one another.
The present invention also provides a dredging apparatus for the recovery of material from below the beds of rivers and other bodies of water. This apparatus comprises the above-described recovery unit which is movably supported on a platform and includes means for raising and lowering the recovery unit. Means are also provided for washing and separating the material removed by the removal means of the primary boom.
The present invention also provides for a method for dredging material from below the beds of rivers and other bodies of water utilizing a dredging apparatus having a primary and secondary boom recovery unit. This method includes the steps of washing and separating the material retrieved by the primary boom on the dredging apparatus whereby the material fines are collected, the washed material is discarded, and the wash water is returned to the body of water with minimal silt disturbance.
The method further includes the steps of separating material ln situ which caves in on the secondary boom and removing the fines separated from the caved-in material to the surface for collection on the dredging apparatus.
BRIEF D~;:SCRIPTION OF THE DRAWINGS
A specific embodiment of the invention is described in further detail with reference to the drawings in which:
FIGURE 1 is a side view of an embodiment of the invention in situ;
rn/kh ~2S~63~i -FIGURE 2a is a cross-section of the recovery unit and FIGURE 2b is an end-view of the unit;
FIGURE 3 is a perspective view of the lower end of the recovery unit showing the primary boom in greater detail;
FIGURE 4 is a schematic drawing of the fines removal system of the secondary boom;
FIGURE 5 is an end-on view of an embodiment of the invention with the recovery unit in a horizontal position, detailing the support structure for the recovery unit;
FIGURE 6 is a schematic drawing of the side view of the recovery unit when in the horizontal position, detailing the structure of its upper end; and FIGURE 7 is a pictorial representa~ion of an embodiment of the invention in operation.
DETAILED DESCRIPTION
. _ ... .
Referring to FIG. 1, the dredging apparatus of the preferred embodiment is shown to basically comprise a floating platform 1, such as two barges combined in a manner similar to a catamaran (see FIG. 5), which supports a recovery unit 22 by means of a mast 5. The platform 1 also supports a wash area 3 at the stern and a hoist 23 which is centrally located. A wash water return hose G leads from wash area 3 to the recovery unit 22. Various storage areas and operation control stations are also present on platform 1 but are not specifically shown in the drawing; ~he platform has an anchor line 2 which is connected to a winch (not shown) on the shore.
rn/kh : ~ --r~ . ' A, , ,.~
ss63s Details of the recovery unit 22 are shown in FIGS. 2 to 4 and 6. The recovery unit 22 includes an upper boom 7 and a lower boom 8. These booms are slidably movable with respect to one another along their longitudinal axes by means of long stroke hydraullc cylinders 4 (see FIGS. 1 and 6), attached at the up~er end and on each side of the recovery unit 22. As shown in FIG. 6, the hydraulic cylinders 4 are attached to the upper and lower booms 7, 8 in an angled manner. Clips 9 are located along the length of both sides of the recovery unit 22 and attach the lower corners of the upper boom 7 and the upper corners of the lower boom 8 together in such a way that the booms are movable with respect to each other along their longitudinal axes only. The clips ~ prevent the booms rom separating from one another and moving independently.
Referring now to FIGS. 2a, 2b and 3, the lower boom 8 includes a support structure for an endless conveyor made up of two parallel loops of connected links 12 which are supported on parallel pairs of transverse rollers 13 at the lower end and parallel pairs of transverse rollers 35 at the upper end.
Although not specifically shown, transverse rollers ara also located in a spaced manner along the length of the lower boom 8 in order to support the connected links 12 in an even manner.
Each pair of rollers rotates on a cylindrical roller shaft 10 which is connected to the support structure of the lower boom in such a way that the shaft 10 can rotate on its longitudinal axis while supporting the rollers and other components of the conveyor. Buckets 11 are attached at each end thereo~ to the loops of connected links 12. The buckets 12, therefore, rn/kh ..
- 12~9635 maintain a constant distance between the loops of connected links 12 and keep the links 12 on the rollers 13 and 35. Rakes (not shown) may be interspersed between the buckets 11 and attached to the loops of connected links 12 in a similar manner as the buckets 11. Such rakes may aid in the filling of the buckets or may help prevent the buckets 11 from catching on boulders or bedrock during operation. The wash water re-turn hose 6 channels water from the wash area 3 into the lower boom 8. The water then follows the downward path of the buckets to the area being worked.
Details of the structure of the upper boom 7 will be described with reference to FIGS. 2a, 2b and 4. As can be seen in FIG 2a, upper boom 7 consists of a hollow ballast chamber 19 having a substantially rectangular cross-section upon which is attached a sluice separator 18, each having distinct functions.
The sluice separator 18 extends from the lower end of the upper boom 7 up to the point along the lower boom 8 which is at the deck level of the floating platform 1. Both sluice separator 18 and ballast chamber 19 are covered by a rectangular shaped solid end cap 17 (FIG. 2b). Means for filling and emptying ballast chamber 19 are located on deck. These means are not shown in the figures but can include pumps and hoses Gr other similar standard equipment available to those skilled in the art.
The sluice separator 18 includes a transversely and longitudinally extending grating 14, a transversely and longitudinally extending fine-mesh screen 15, a fines chamber 2 rnfkh and a pipe system 20, 21 including a venturi nozzle 16 [see FIG.
4]. The grating 14 includes transversely extending parallel bars which prevent large pieces of material from damaging the fine-mesh screen 15 which is located a short distance beneath it. The mesh size of the fine-mesh screen 15 will depend on the size of the particles that are to be collected. ~lternatively, several different screens can be used in the sluice separator, placed one above another and ranging from a coarse mesh on top to a fine meshed screen on the bottom. In this manner, only the very fine material will be in contact with the fine screen, thus preventing damage to the screen by large objects that would normally pass through the grating 14.
The fines chamber 24 has a rectangular cross section, its upper surface being the fine-mesh screen 15. Within fines chamber 24 is the pipe system 20, 21. A pipeline 20 o~ circular cross section extends from deck level to the lower end of the upper boom 7 along a bottom corner of the fines chamber 24. At the lower end, pipeline 20 has a right angle bend to a short section running parallel to the end cap 17 and ends with a venturi nozzle 16. The venturi 16 has a frustoconical portion ending with a cylindrical portion of lesser cross sectional area than that of pipeline 20, thereby causing the velocity o~ the fluid being transported through pipeline 20 to be increased when exiting the nozzle.
Pipeline 21 is of similar configuration to that of pipeline 20, however, it extends from deck level to the lower end of the upper boom 7 along the opposite bottom corner of fines chamber 24. The pipeline 21 does not have a venturi rn/kh ~L~5~363S
, nozzle at its end. In order to create a negative pressure in the fines chamber 24 so that the ~ines will be transported to the deck through pipeline 21, the venturi 16 of pipeline 20 is inserted into the opening of pipeline 21. The circumferential gap ~see FIGS. 2a and 4] that occurs between the outer perimeter of the venturi 16 and the inner perimeter o~ pipeline 21 aiiows material to flow through it and into pipeline 21.
Means for pumping a 1uid through pipeline 20 are located on the deck of the platform 1, but are not specifically shown in the figures. Also on the deck but not shown are collection means for the fines that are brought to the surface through pipeline 21.
The recovery unit 22 is supported by a mast 5 which is further supported by the support structure 29. The support structure 29 and the means of attachment of the recovery unit 22 and mast 5 to it are presented in FIG. 5. FIG. 5 depicts the support structure 29 as a framework located on and supported by the floating platform 1. Cylindrical shafts 25 which are used to pivot the recovery unit 22 during operation are rotatably supported on either side of the recovery unit 22 by pillow blocks 26 having bushings through which shafts 25 pass. In the embodiment shown in FIG. 5, there are four pillow blocks 26 which are bolted to the support structure 29 supporting the shafts 25 proximally and distally to recovery unit 22.
Attached to the proximal end of each shaft 25 is a cylindrical roller 28. Each roller 28 rests between guides 27 defined by vertically spaced elongated sections of angle irons.
These guides 27 (see also FIG. 6) are attached to the lower rn/kh ~;~5963~i;.
boom 8 in such a way that the pivot point of the recovery unit 22 is slightly below the level of roller shafts 10 o~ the lower boom 8.
The mast 5 (not shown in FIG. 5) is attached to support structure 29 at pivot~ble attachment points 30. In this embodiment of the invention, attachment points 30 are attached to the support structure 29 at four points, two on either side of recovery unit 22. The mast 5 moves with the recovery unit 22 at all times.
In FIG. 6, the upper end of the recovery unit 22 is depicted at A and the part of the unit that is at and just below deck level when the unit is submerged is depicted at B. The side view o~ the recovery unit 22 shows in general, the upper and lower booms 7, 8, connecting clips 9 and buckets 11. The sluice separator 18 is shown at B to end at deck level. Guides 27 are attached to lower boom 8.
At A, buckets 11 empty their contents into hopper 31, rotate over rollers 35 and are then trànsported within the lower boom 8 to the lower end of the recovery unit 22. Rollers 35 at the upper end of lower boom 8 are the only pair of rollers in the endless conveyor which have a drive mechanism connected thereto (not shown). This mechanism rotates rollers 35 and causes the endless conveyor to move. The hopper 31 has t~o side panels located on either side of the recovery unit 22 which attach to the mas~ 5 above the recovery unit 22 at pivot point 36~ The hopper 31 is pivotable so tha~ it can remain vertical when the recovery unit and mast are at different angular positions during operation. The hopper 31 is shaped like a rn/kh ~2~96~i large funnel. Its lower tube-like portion is directed into the wash area 3 (see FIG. 1).
The hydraulic cylinders 4 are connected to a standard hydraulic pump and control system ~not shown) which is located on the deck of the floating platform 1.
The recovery unit 22 is connected to mast 5 by means of a lug 34, cable 33 and pulley 32. The lug 34 is attached to the upper end of the lower boom 8 and the pulley 32 is located at the upper end of the mast. Cable 33 is connected at deck level to hoist 23. A multiple pulley system could also be used in order to reduce the amount of work required to move the boom. Note that the recovery unit 22 is generally raised to float on the water and lowered into the water by emptying or filling the ballast chamber 19 of the upper boom 7 with water.
When the recovery unit 22 is to be raised from the floating position to a horizontal position above the water level, hoist 23 and pulley 32 are utilized.
The operation of the dredging apparatus as it i5 used when practicing the preferred method of the invention will now be described.
The preferred embodiment of the invention provides a dredging apparatus for use in rivers or other bodies of water for material removal and separation of diluvial material taken from below the riverbed. In particular, this apparatus is designed for use in placer gold recovery operations.
Firstly, the floating platform 1 is moved to the desired location in the river and is anchored to the shore by means of the anchor line 2 (see FIGS. 1 and 7) which is attached _g_ rn/kh 125~3~;
on the shore to a winch. The recovery unit 22 is in an almost horizontal position floating on the water, the ballast chamber 19 filled with air.
Once the platform 1 is positioned, dredging is commenced. In order to lower the recovery unit into the water, the ballast chamber 19 is flooded with water. The recovery unit 22 pivots about the rollers 28 between the guides 27. Depending on the conditions of the material being dredged, weighted mud may be used with water in the ballast chamber 19 to provide more weight to the recovery unit.
When the end of the recovery unit 22 hits the riverbed, the operation of the endless conveyor is begun. The buckets 11 on the endless conveyor dig into the riverbed while removing material to the surface. The filled buckets 11 empty their contents into the hopper 31 tFIG. 6) and then travel over rollers 35 and back through the inner portion of the lower boom 8.
As the buckets 11 dig a channel into the riverbed, material on either side of the channel may cave in onto the grating 14 of the upper boom 7 ~FIG. 2a]. The material which passes through the grating 14 falls onto the fine-mesh screen 15 which separates the fines from the coarser material. The fines which pass through ~he fine-mesh screen into the fines chamber 24 settle toward the lower end o~ the upper boom 7 due to gravity and negative pressure. The negative pressure is caused - by pressurized air flowing from pipeline 20 through the venturi nozzle 16 at an increased velocity and into pipeline 21. The negative pressure draws the water containing the fines through rn/kh ~2S~6~
the circumferential gap bet~een the venturi 16 and opening of pipeline 21 and into pipeline 21 through which it is transported to the deck where it is collected. The collection means may simply be storage tanks where the fines and water are kept until they are removed to the shore for final settling and separation. Alternatively, settling tanks or hydrocyclones may be present on deck to effect final separation in situ.
As previously mentioned, the material recovered by the buckets 11 of the lower boom is emptied into the hopper 31. The hopper 31 feeds the material into the wash area 3 located on the deck of the plat~orm 1 for washing and separation. The wash area can comprise a sluice separator which separates the large pieces of gravel or rock from the fines. The washed gravel and rocks are disposed of overboard into an area that is not to be dredged or has already been dredged. The fines are collected for storage prior to final separation and processing on shore.
The cleaned wash water is returned through the hose 6 to the river. In order to prevent a large amount of silt disturbance from occurring, thç wash water is returned through the hose 6 into the lower boom 8 where it follows the downward path of the buckets ll.
When the recovery unit has dug down to the desired depth in the riverbed, the entire dredging apparatus is gradually moved by means of the anchor-line 2 and winch towards the shore as shown in FIG. 7. As can be seen in FIG. 7 r dredging has just begun at position A and the recovery unit 22 has reached the desired depth in the riverbed. As the winch pulls the apparatus toward the shore, the buckets ll of the rn/kh 1259~
endless conve~or dig into the riverbed and recover more material. If the recovery unit 22 encounters a boulder which is too large to be dug out (as seen between positions A and B), the lower and upper booms, 8 and 7, are moved relative to one another by means of the hydraulic cylinders 4 so that they "walk" over the boulder. The buckets 11 of the endless conveyor continue to remove material as the unit moves over the boulder and back down to the desired depth. Between positions B and C, the recovery unit 22 is shown to be removing material from just above the bedrock. At position ~ the dredging apparatus has almost reached the shore and dredging the channel is completed.
The recovery unit is then "walked" out of the channel that has been dug. The water in the ballast chamber 19 is pumped out so that the recovery unit 22 rises to float on the surface of the river. The dredging apparatus can then be moved back to position A to repeat the dredging method a short distance away and parallel to the location previously dredged.
An important feature of the dredging apparatus of the preferred embodiment is that the recovery unit 22 is pivotably raised and lowered passively in the water by means of the ballast chamber 19 being filled with air or water. The hoist 23 is only used when the recovery unit 22 is to be raised out of the water into the horizontal position. This is done when repairs and maintenance to the recovery unit 22 are being performed, or when the dredging apparatus is to travel long distances in the water.
The preferred embodiment has been described utilizing a floating platform 1. Alternatively, the platform could be rn/kh ~L2~63~;i based on land, depending on the location to be dredged. The land based platform could be mounted for example, on tracks, wheels or a skid. The platform could still be moved by means of a winch and anchor-line 2.
In the preferred embodiment end cap 17 completely covers both the sluice separator 18 and ballast chamber 19.
Alternatively, the end cap 17 may completely cover the ballast chamber 19 and fines chamber 24 while having a grating having transversely extending parallel bars extending across the area between grating 14 and fine-mesh screen 15. In this way, material passing through gxating 14 but too large to pass through the fine-mesh screen 15 will be able to pass through the grating o end cap 17 thereby preventing the area between grating 14 and fine-mesh screen 15 from getting clogged.
The preferred embodiment of the apparatus has been described using specific components. It will be readily apparent to those skilled in the art that many types of standard, readily available components can be used to construct the dredging apparatus. For example, the hydraulic cylinders ~
used to move the upper and lower booms, 7 and 8, relative to one another can be replaced by a pulley or rack and pinion arrangement. The buckets 11 can also be of various shapes depending on the type and the conditions of the material that is to be dredged. Different shaped buckets can be alternated on the conveyor so that the material can be more efficientl~
loosened and remoYed. As previously mentioned, rakes can also be interspersed with the buckets in order to loosen the material. There are many ways in which the buckets and conveyor rn/kh ~L25963~
can be assembled in order that the material being dredged easily falls into hopper 31. The material can fall into the hopp~r by means of gravity, or high pressure water jets may be used to empty out the buckets. Although not shown in the drawings, the upper end o~ the endless conveyor may also be altered so that the conveyor makes an angle downward over additional rollers 35 so that the openings o~ the buckets 11 are inverted downward and the material held therein is emptied into the hopper 31.
Further alterations and variations to the apparatus will be readily apparent to those skilled in the art, therefors the scope of protection to the present invention is not intended to be limited by the above described embodiments, but solely by the claims attached hereto.
rn/kh
Claims (20)
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A dredging apparatus for the recovery of material from below the beds of rivers and other bodies of water comprising:
a recovery unit movably supported on platform means, consisting of a lower primary boom, an upper secondary boom and means for longitudinally moving the booms relative to one another;
said primary boom having an endless conveyor with material digging and removal means attached thereto;
said secondary boom having material separating means and means for removal of separated material;
means for washing and separating the material removed by said removal means of said primary boom; and means for raising and lowering said recovery unit;
whereby during dredging,said recovery unit is lowered to the bed of the body of water, said primary boom digs and removes material to the washing and separating means while any material which caves in on said recovery unit is separated and removed by said separating and removal means of said secondary boom.
a recovery unit movably supported on platform means, consisting of a lower primary boom, an upper secondary boom and means for longitudinally moving the booms relative to one another;
said primary boom having an endless conveyor with material digging and removal means attached thereto;
said secondary boom having material separating means and means for removal of separated material;
means for washing and separating the material removed by said removal means of said primary boom; and means for raising and lowering said recovery unit;
whereby during dredging,said recovery unit is lowered to the bed of the body of water, said primary boom digs and removes material to the washing and separating means while any material which caves in on said recovery unit is separated and removed by said separating and removal means of said secondary boom.
2. A dredging apparatus as in claim 1, wherein said means for moving the booms relative to one another includes long stroke hydraulic cylinders.
3. A dredging apparatus as in claim 1, wherein said material digging and removal means of the primary boom comprises an endless conveyor having buckets attached thereto in a spaced manner for continuous digging and removal of material.
4. A dredging apparatus as in claim 3, further including rakers interspersed between said buckets on said conveyor.
5. A dredging apparatus as in claim 1, wherein said material separating means of said secondary boom comprises a sluice-type separator.
6. A dredging apparatus as in claim 1, wherein said means for removal of separated material comprises a pipe having supply and return sections fluidly connected by a venturi nozzle.
7. A dredging apparatus as in claim 1, further including a flotation means on said secondary boom comprising a chamber adapted to be filled with air for flotation of said recovery unit or water to submerge said recovery unit.
8. A dredging apparatus for the recovery of material from below the beds of rivers and other bodies of water comprising:
a double boom recovery unit movably supported on platform means, having a lower primary boom, an upper secondary boom and means for longitudinally moving the booms relative to one another by use of long stroke hydraulic cylinders;
said primary boom having an endless conveyor with attached buckets for digging and removing diluvial material from the river bed;
said secondary boom having a sluice separator, means for removal of fines separated by said sluice and a ballast chamber;
means for washing and separating the material removed by said buckets of said primary boom; and means for raising and lowering said recovery unit;
whereby during dredging,said recovery unit is lowered to the bed of the body of water, said primary boom digs and removes material to the washing and separating means while any material which caves in on said recovery unit is separated and removed by said separating and removal means of said secondary boom.
a double boom recovery unit movably supported on platform means, having a lower primary boom, an upper secondary boom and means for longitudinally moving the booms relative to one another by use of long stroke hydraulic cylinders;
said primary boom having an endless conveyor with attached buckets for digging and removing diluvial material from the river bed;
said secondary boom having a sluice separator, means for removal of fines separated by said sluice and a ballast chamber;
means for washing and separating the material removed by said buckets of said primary boom; and means for raising and lowering said recovery unit;
whereby during dredging,said recovery unit is lowered to the bed of the body of water, said primary boom digs and removes material to the washing and separating means while any material which caves in on said recovery unit is separated and removed by said separating and removal means of said secondary boom.
9. The apparatus as in claim 8, further including rakers attached to the endless conveyor of said primary boom between said buckets.
10. The apparatus as in claim 8, wherein said means for removal of fines separated by said sluice separator comprises a pipe having supply and return sections fluidly connected by a venturi nozzle.
11. A dredging apparatus as in claims 1 or 8 including hull means for floatably supporting said platform means on a body of water.
12. A dredging apparatus as in claims 1 or 8 including means for supporting said platform means on land.
13. A method for dredging material from below the beds of rivers and other bodies of water utilizing a dredging apparatus having a primary and secondary boom recovery unit including the steps of:
washing and separating material retrieved by said primary boom on said dredging apparatus whereby the fines of said material are collected, the washed material discarded, and the wash water returned to the body of water with minimal silt disturbance;
separating material in situ which caves in on said secondary boom; and removing fines separated from the caved-in material to the surface for collection on said dredging apparatus.
washing and separating material retrieved by said primary boom on said dredging apparatus whereby the fines of said material are collected, the washed material discarded, and the wash water returned to the body of water with minimal silt disturbance;
separating material in situ which caves in on said secondary boom; and removing fines separated from the caved-in material to the surface for collection on said dredging apparatus.
14. A recovery unit for use in a dredging apparatus comprising:
a lower primary boom having an endless conveyor with material digging and removal means attached thereto;
an upper secondary boom having material separating means and means for removal of separated material; and means for longitudinally moving said primary and secondary booms relative to one another.
a lower primary boom having an endless conveyor with material digging and removal means attached thereto;
an upper secondary boom having material separating means and means for removal of separated material; and means for longitudinally moving said primary and secondary booms relative to one another.
15. A recovery unit as in claim 14, wherein said means for moving said booms relative to one another includes long stroke hydraulic cylinders.
16. A recovery unit as in claim 14, wherein said material digging and removal means of the primary boom comprises an endless conveyor having buckets attached thereto in a spaced manner for continuous digging and removal of material.
17. A recovery unit as in claim 16, further including rakers interspersed between said buckets on said conveyor.
18. A recovery unit as in claim 14, wherein said material separating means of said secondary boom comprises a sluice-type separator.
19. A recovery unit as in claim 14, wherein said means for removal of separated material comprises a pipe having supply and return sections fluidly connected by a venturi nozzle.
20. A recovery unit as in claim 14, further comprising a ballast chamber adapted to be filled with air for flotation of said unit or water to submerge said unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000553591A CA1259635A (en) | 1987-12-03 | 1987-12-03 | Diluvial diving dredge |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000553591A CA1259635A (en) | 1987-12-03 | 1987-12-03 | Diluvial diving dredge |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1259635A true CA1259635A (en) | 1989-09-19 |
Family
ID=4137005
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000553591A Expired CA1259635A (en) | 1987-12-03 | 1987-12-03 | Diluvial diving dredge |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1259635A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0683274A1 (en) * | 1994-05-18 | 1995-11-22 | Barrages Services International BV | Vessel, dredging means and assembly thereof |
| CN112627271A (en) * | 2020-12-16 | 2021-04-09 | 章红妹 | Irrigation ditch silt extraction equipment for irrigation |
-
1987
- 1987-12-03 CA CA000553591A patent/CA1259635A/en not_active Expired
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0683274A1 (en) * | 1994-05-18 | 1995-11-22 | Barrages Services International BV | Vessel, dredging means and assembly thereof |
| NL9400818A (en) * | 1994-05-18 | 1996-01-02 | Barrages Services Int Bv | Vessel, dredging equipment and combination thereof. |
| US5638620A (en) * | 1994-05-18 | 1997-06-17 | Barrages Services International B.V. | Dredging vessel, dredging assembly and method of dredging |
| CN112627271A (en) * | 2020-12-16 | 2021-04-09 | 章红妹 | Irrigation ditch silt extraction equipment for irrigation |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5261171A (en) | Pipeline padding machine attachment for a vehicle | |
| CN112726716A (en) | Plain river bottom sludge cleaning device and cleaning method thereof | |
| WO2018178088A1 (en) | Autonomus dredging underwater device | |
| EP0438683B1 (en) | Method and device for dumping fine material on the sea bed or slopes during dredging | |
| CN114411847B (en) | Multifunctional hydraulic engineering dredging device | |
| RU2034151C1 (en) | Floating clamshell dredger for mining sand and gravel | |
| US5540003A (en) | Padding machine with shaker for separator | |
| US3433531A (en) | Method and apparatus for undersea mining | |
| US4585274A (en) | Mineral and metal particle recovery apparatus and method | |
| US3855807A (en) | Pipe transporting and laying vehicle and method | |
| CA1259635A (en) | Diluvial diving dredge | |
| JP4131511B2 (en) | Underwater walking work machine and work method of underwater walking work machine | |
| US3761132A (en) | Apparatus and method for repositioning earthen material | |
| CN214460762U (en) | Ditch desilting structure | |
| US4366052A (en) | Controlled flooding and skimming apparatus for beach cleaning | |
| US4302339A (en) | Beach cleaning method | |
| JP7107767B2 (en) | Dredging station and dredging system | |
| DE3129228A1 (en) | Underwater suction scraper-dozer | |
| EP1584754B1 (en) | Method for removal of sand | |
| RU2107776C1 (en) | Method of underwater digging operations with use of suction-tube dredge and hydraulic giant for underwater trenching | |
| CN212548472U (en) | Sand screening device for sand extraction construction | |
| RU2081321C1 (en) | Method for mining diamond-carrying kimberlite pipes | |
| CN214940580U (en) | Dredger fill-out screening barge platform | |
| RU32142U1 (en) | Dredger shell | |
| KR102519147B1 (en) | Subsea sediment collection device for suctioning and collecting sediment in the sea |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |