JPS6340918B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention uses a water flow generated in an ore collection duct while moving on the seabed to suck up nodules such as manganese nodules existing on the seabed through a suction head provided at the tip of the duct. This invention relates to an ore collection device for collecting manganese nodules, etc.

The case of manganese nodules will be described below, but the present invention can also be applied to ore collectors similar to manganese nodules.

Manganese nodules, which are attracting attention as an inexhaustible mineral resource of nickel, cobalt, copper, manganese, etc., are found flatly on the seafloor sediments of the deep sea floor, as if laid out on boulders. Therefore, in order to mine this ore, it is necessary to collect the nodules distributed on the ocean floor and then lift the ore to the sea.

As a manganese nodule collector, the so-called fluid dredge method mentioned at the beginning is superior because it has a simple mechanism and fewer breakdowns.

Now, the seabed where manganese nodules exist is not necessarily flat, but has ups and downs, upslopes and downslopes, and the places where they change are arc-shaped or ridges at certain angles. In some cases, this is done. It is said that when designing a manganese nodule concentrator, it is necessary to keep in mind a seabed slope of about 8/100 at most.

In addition, seafloor sediments are generally soft, but the degree of softness is not uniform, and the bearing capacity ranges from 200 to 700 kg/m ² . For this reason, ore collectors are generally mounted on skis with a large contact area and supported on the seabed, but the amount of sinking of the ski changes depending on the softness of the seabed, and the difference is approximately 30 cm. reach even.
Furthermore, if the ski rides on the ridgeline of the above-mentioned seabed slope, a portion of the ski may sink into or separate from the seabed. As a result, if the suction head is too far from the seabed, it will only suck in seawater, and if the suction head sinks below the seafloor, it will suck in a large amount of seafloor sediment like a dredge.

The state of manganese nodules on the ocean floor varies from those that are completely exposed, like a ball rolling on the ground, to those that are about half exposed above the ocean floor, and those that are almost completely submerged under the ocean floor, like an iceberg. etc. It varies.

In addition, the size of manganese nodules varies, but due to considerations such as the diameter of the ore lifting pipe and economic efficiency, those with a low abundance, for example, large diameters of 80 to 100 mm or more, are selected to prevent them from entering the suction head. It is necessary to eliminate it.

Considering the above-mentioned seabed topography, soil quality, and condition of manganese nodules, the suction head of the ore collecting device adjusts the relative height and inclination with the seabed surface, and is designed to collect large-diameter nodules that exceed the predetermined ore collapse grain size range. It is necessary to operate while sorting and eliminating.

Conventionally, as means for adjusting the position and inclination of the suction head, a bellows is installed between the ore collection duct and the suction head, and the height of the seabed is adjusted by the expansion and contraction of the bellows.
A method has been proposed in which the bellows follows changes in slope, but in order to follow changes in seabed height of approximately 30 cm, the length of the bellows would be extremely long, and the bellows have a thin wall, so the bellows would have to pass through the inside. Nodules cause rapid wear and shorten the lifespan. Furthermore, there are various problems such as the inability to reliably transmit the towing force from the mother ship to the suction head. If the thickness of the bellows were increased to increase its strength, it would be difficult to follow the height and slope of the seabed.

In addition, as a so-called primary nodule sorting means for sorting and eliminating large-diameter nodules that exceed the lifted ore grain size range, conventional nodules are sorted vertically in front of the suction head in a direction diagonal to the direction of movement above and below the seabed surface. A method has been proposed in which a grid is provided and the nodules to be excluded are pushed outward, but in order for this sorting device to smoothly push out large-diameter nodules outward, it is necessary to It is necessary that the angle to the filter be quite acute, and as the width of the suction head increases, the disadvantage arises that this sorting device becomes very large.

The present invention eliminates the above-mentioned drawbacks associated with the suction head of conventionally proposed ore collectors, and allows the suction head to reliably follow the seabed height and inclination with a simple configuration without using bellows. It is an object of the present invention to provide a manganese nodule collector capable of smoothly sorting and removing large-diameter nodules using members much smaller than conventional ones.

Hereinafter, the present invention will be explained in detail based on drawings showing embodiments thereof.

The ore collecting device according to the embodiment of the present invention shown in FIGS. 1 and 2 includes a hopper 1 substantially configured as a closed container, and a plurality of hoppers (four in the figure) extending forward from the hopper 1. An ore collection duct 2, a suction head 3 attached to its hanging tip, a muddy water discharge pipe 4 extending rearward from the hopper 1 and opening to the open sea, and an ore collection pump 5 provided in the middle thereof and its drive. A motor 6 and an ore lifting pipe which is connected to the nodule discharge port 1a at the bottom of the hopper and which tows the ore collecting device by a mother ship on the sea (not shown) and lifts the nodules to the mother ship using an ore lifting pump (not shown) installed on the way. These devices are mounted on one frame 9. Note that the ore lifting connecting pipe 8 and frame 9 are omitted in FIG. 2 to avoid complexity. A bumper 10 is attached to the front end of the frame 9 via a spring 11 for cushioning when the ore collector collides with an obstacle while being towed.

At a position immediately in front of the part of the frame 9 that fixes the ore collecting duct 2, that is, at a position directly above the suction head 3, one end of the arm 12 is attached at five locations between the four suction heads and on both outsides in the direction of movement of the ore collector. An arm 12 is pivotally supported so as to be able to swing in a vertical plane parallel to , and a seabed height detection wheel 13 is pivotally supported at the other end of the arm 12 so as to be rotatable around a horizontal horizontal axis. ing. The specific gravity of the wheel 13 is adjusted to be slightly higher than that of seawater by filling the interior with a buoyancy material, etc., so that when the ore collecting device moves forward, it does not sink into the surface of the seabed sediments and does not bounce up due to reaction etc. It is designed to be able to roll while constantly touching the seabed without wobbling.

A plurality of guide tubes 14 are vertically arranged in four rows on the lower surface of the frame 9, and correspondingly, a column 16 whose lower end is pivotally supported on the upper surface of the ski 15 is loosely fitted into the guide tube 14. are doing. A compression spring 17 is provided around the column 16, and the weight of the frame 9 and the device mounted thereon is supported by the ski 15 via the spring 17. The skis 15 are made of a flexible steel plate or the like, and bend to follow the seabed topography, so the skis do not partially sink into the seabed sediments or become loose from the seabed surface.
Furthermore, application of excessive force to the frame 9 due to the expansion and contraction of the spring 17 is also prevented.

Next, details of the suction head will be explained with reference to FIGS. 3 and 4. As shown in FIG. 4, each suction head 3 is attached at a predetermined angle to a support shaft 20 provided in the front and back direction on the center line of the front and rear walls at the lower end of the ore collecting duct 2, which has a rectangular cross section and whose tip gradually widens laterally. It is pivotally supported so as to be swingable within a range (that is, an angular range corresponding to the above-mentioned seabed slope of 8/100). This swing range is limited by a stopper 20' attached to the side wall of the ore collecting duct.

The suction head 3 is connected to a suction head member 21 in the shape of a rectangular frame that is pivotally supported by the support shaft 20 and surrounds the end of the ore collecting duct 2 with a slight clearance, and to both side plates of the member. A pair of vertical suction head side plates 22 are fixed downwardly and extend in the moving direction of the ore collecting device, and the upper ends of the neck member 21 are connected to the lower ends of the front and rear walls of the neck member 21, respectively. It has supported suction head front and rear plates 23, 24. The height of the suction head opening surrounded by the inner surfaces of the pair of suction head side plates 22 and the front and rear blades 23, 24 relative to the frame 9 changes depending on the swinging positions of the front and rear blades 23, 24.
A slight clearance is provided between both side edges of the front and rear blades 23, 24 and the suction head side plate 22.

As shown in FIG. 3, the suction head side plate 22 extends above and below the seabed surfaces BL, BL' at the high and low positions, and extends to a certain range before and after the range of the front and rear blades 23, 24, and its lower edge is located at the front end. It descends rearward from a point on the seabed surface at an inclination of about 30 degrees to the horizon, and points horizontally rearward from just below the neck member 21.

Between the side plates 22, a plurality of flat bars 25 are arranged in parallel with the lower edges thereof at intervals of the maximum diameter of the lifted ore nodules, forming a grid for primary nodule sorting.

Since this device is constructed as described above, when it is lowered to the seabed and the ore collection pump 5 is operated while being towed by the mother ship, the pressure inside the hopper 1 is lower than the pressure in the open sea, and the pressure inside the suction head 3 is lowered than the pressure in the open sea. Seawater flows into the ore collection duct 2 along with nearby manganese nodules and seabed sediments from the opening formed by the side plates 22 and the front edges of the front and rear blades 23 and 24, and enters the hopper 1. When the flow rate decreases, the nodules fall to the bottom of the hopper 1 due to their own weight and accumulate, and the seafloor sediments are suspended in the seawater and drained into the muddy water discharge pipe 4.
is discharged into the sea. The nodules accumulated at the bottom of the hopper are sequentially supplied to the ore lifting connecting pipe 8 through the lower opening 1a, and are turned into slurry together with seawater flowing in through the nodule slurry concentration adjustment valve 19, and the ore is lifted through the ore lifting pipe 7 to the mother ship at sea. Ru.

The height of the seabed immediately before the suction head 3 (relative height to the frame 9) and the cross-sectional shape of the seabed in the left and right direction are determined by the five seabed height detection wheels 1.
The angle θ between the arm 12 and the frame 9, which changes with the vertical movement of the frame 3, can be easily detected with sufficient accuracy for practical use. In this case, when the seabed height detection wheel 13 passes over the nodule, the wheel rises momentarily, so it is preferable to exclude very short-term changes in the angle θ from the measurement.

For example, as shown in FIG. 5, if the cross-sectional shape of the seabed in the width direction of the suction head has a ``h''-shaped slope across the entire scanning width of the suction head, the five seabed height detection wheels 13 Since the heights are different from each other, the amount of seafloor inclination and the position of the ridge can be easily detected from the respective detection signals. Based on this detection signal, a hydraulic drive device (not shown) rotates the neck member 21 of each suction head 3 around the support shaft 20 according to a predetermined program, as shown in FIG. Each suction head can be adapted to the local seabed slope.

In addition, as shown in FIG. 3, the suction head front and rear blades 23, 24 are driven by a hydraulic drive device (not shown) based on a detection signal from a seabed height detection wheel, and the dashed lines and solid lines in FIG. By displacing the suction head to an appropriate position between the two positions indicated by , the suction head opening position can be adapted to the seabed height.

As shown in FIG. 3, the suction head front blade 23 has a cross-sectional shape in which the front edge is strongly curved upward, and the rear blade 24 has a gentle arc shape, so that external seawater does not flow along the blade. It is easy to flow into the suction head, and the rear blade 2
By placing the tip of No. 4 at a position slightly below the seabed surface, it is possible to capture not only nodules lying on the surface of seabed sediments, but also nodules that are partially buried in the sediment, and nodules that are almost completely submerged in the sediment. Like harvesting potatoes with a plow, they can be dug up and collected in the suction head. Depending on the quality of the seabed soil and the presence of manganese nodules, it is also possible to increase the area of the suction port by displacing the rear blade 24 to the position 24' shown by the dashed line in Fig. 3. .

When suctioning seawater and nodules from the suction head, due to the pressure difference between the inside and outside of the suction head, the outer surface of the ore collecting duct 2 and the suction head member 2
Although water from the outside flows into the suction head or the ore collecting duct through the clearance between the outer surface of the suction head and the outer surface of the suction head and the clearance between the side edges of the suction head front and rear blades 23 and 24 and the inner surface of the suction head side plate, the clearance is small. Also, since there is viscous resistance, not only can the amount of inflow be ignored, but water flowing through this gap washes away foreign matter such as seabed sediments that have entered the gap, making the operation smoother. I can do it.

Between the lower edges of the suction head side plates 22 on both sides, a grid in which a plurality of flat bars 25 are arranged in parallel at intervals of a predetermined sorting grain size is provided as a primary nodule sorting means. Nodules pass through this lattice and are sucked into the suction head, but nodules with a larger particle size are blocked by this lattice and cannot enter the suction head, and as the ore collector moves forward, The lower surface of the slanted lattice allows it to be pushed downward through seafloor sediments. Since the depth of pushing down the nodules is only a few tens of centimeters at most, this sorting grid can be made much smaller than the conventional primary sorting means that pushes out a width of several meters in the lateral direction.

In the above embodiment, the inclination of the suction head and the height of its opening are automatically adjusted via the hydraulic system based on the detection signal from the seabed height detection wheel. In addition to this, various known methods such as the use of sound waves can be used. In addition, the height adjustment of the suction head opening may be set in advance at a position suitable for the condition of the seabed soil, etc., if it is known in advance, or it may be done by remote control from the mother ship at sea. .

As described above, according to the present invention, with a simple configuration,
Since the height and slope of the suction head can be adjusted in accordance with the seabed topography and soil quality to perform the primary sorting of nodules, a remarkable effect can be obtained in improving the lifting efficiency of manganese nodules, etc.

[Brief explanation of the drawing]

FIG. 1 is a side view of an ore collector according to an embodiment of the present invention;
Figure 2 is a plan view with some parts omitted;
FIG. 3 is a longitudinal sectional view showing the suction head in detail, FIG. 4 is a front view thereof, and FIG. 5 is a front view showing an example of a state in which each suction head is inclined in accordance with the inclination of the seabed surface. 2...Ore collection duct, 3...Suction head, 9...
Frame, 12... Arm, 13... Seabed height detection wheel, 20... Suction head support shaft, 21...
Suction head neck member, 22... Suction head side plate, 23... Suction head front blade, 24... Suction head rear blade, 25...
Flat bars (bars that form a sorting grid).

Claims (1)

[Claims] 1 Manganese nodules and other nodules existing on the seabed are sucked in from the suction head provided at the tip of the ore collection duct by a water flow generated in the ore collection duct while moving on the seabed. In the ore collector, at least a slope of approximately 30° from horizontal to a position at a moderate height above the seabed in front of the suction head of the suction head to a position below the seabed almost immediately below the suction. At least at the suction head, a lattice is formed by arranging a plurality of rods in parallel with the maximum grain size range of the manganese nodules to be collected at intervals of a plurality of rods that extend backward in a generally horizontal direction. 1. An apparatus for collecting manganese nodules, etc., characterized by having a primary nodule sorting means provided in a width range of .