JPS5891291A - Device for collecting manganese nodule - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ore collector for mining manganese nodules existing on the seabed.

Manganese nodules, which are attracting attention as inexhaustible mineral resources such as nickel, cobalt, copper, and manganese, are deposited flatly on the surface of seafloor sediment (mud) on the deep ocean floor thousands of meters deep, as if spread with gravel. Therefore, when mining, it is not possible to grab a large amount of nodules at once using a grab bucket or the like, but rather to collect the nodules from a wide area using a mining device and then lift them to a mother ship at sea. It is necessary to mine.

Various methods have been considered for collecting and lifting equipment for manganese nodules, but a suction head with a wide suction port uses negative pressure to suck up manganese nodules along with a water flow into an ore collecting duct). The so-called fluid dredge method, which collects ore and supplies it to an ore lifting pipe that generates an upward water flow using an ore lifting pump and lifts the ore to a mother ship at sea, has high mining efficiency.
It's a good method.

When collecting manganese nodules using this method, not only manganese nodules but also fine-grained seafloor sediments (so-called mud and clay) are collected.
Since the ore is also sucked out from the suction head, if it is unloaded together with the manganese nodules to the mother ship at sea, not only will the lifting efficiency decrease, but it will also be separated from the manganese nodules. Discharging sediment along with seawater to the sea surface causes environmental pollution.Therefore, fine-grained seafloor sediments are sucked into the suction head and the ore collecting duct along with seawater and nodules using centrifugal force, gravity, and mesh. , or by using these in combination, the nodules are separated and discharged into the sea together with seawater, thereby preventing the sediment from being lifted into the sea.

By the way, when lifting ore through an ore lifting pipe using a full water flow of manganese nodules, if the nodule slurry concentration is low, the energy of the lifting ore bonder is used to lift the water, which is inefficient, and if the slurry concentration is too high, the slurry The efficiency of ore lifting actually decreases due to factors such as specific gravity and friction. Therefore, there is an optimum slurry concentration suitable for efficiently lifting manganese nodules in the required particle size range.

Conventionally, to adjust the concentration of manganese nodule slurry in the ore lifting pipe, it was common to install a screw feeder at the nodule outlet at the bottom of the hopper of the ore collector and adjust the rotation speed to adjust to the desired slurry concentration. Met. However, if such a mechanical adjustment means is installed in a passageway through which manganese nodules continuously pass, there is a high possibility that performance will change due to wear and failures such as clogging will occur. It is difficult to say that it is suitable for equipment that operates on the seabed at depths of 500 m.

In view of the above-mentioned problems of the adjustment means provided in the manganese nodule collecting device for adjusting the concentration of nodule slurry in the ore lifting pipe of the conventional manganese nodule mining system, the present invention has a simple structure, wears away due to the passage of manganese nodules, It is an object of the present invention to provide a manganese nodule collector having a means for easily adjusting the slurry concentration in an ore lifting pipe to an optimum value without fear of such problems.

Hereinafter, the present invention will be explained in detail with reference to drawings showing embodiments thereof.

In the apparatus according to the embodiment of the present invention shown in FIGS. 1 and 2, a hopper 2 is mounted on a pair of left and right sleds. At the front of the sled 1, a suction head 8 is provided which extends perpendicularly to the direction of travel and opens close to the seabed surface when this device is placed on the seabed.
An ore collecting duct 4 connecting the upper part of the front side wall of the hopper 2 is installed. A muddy water discharge pipe 5 is provided rearward from the upper part of the rear side wall of the hopper 2, and its rear end opens to the open sea. An ore collecting pump 6 is provided in the middle of the muddy water discharge pipe 5. The upper surface of the hopper 2 is closed with a top plate 2a, and the hopper 2 is formed as a substantially airtight container that can maintain the required negative pressure when the ore collection bonder 6 is operated. A connecting pipe 7 for lifting ore is connected thereto.

A seawater intake pipe 8 for adjusting the nodule slurry concentration is connected to the vicinity of the connection end of the ore lifting connecting pipe 7 to the nodule discharge port 2b at the lower end of the hopper, and the other end is open to the open sea. A nodule slurry concentration adjustment valve 9 whose opening degree can be adjusted is provided in the middle of the seawater intake pipe 8. A nodule slurry concentration detector 10 is provided in the middle of the ore lifting connecting pipe 7, and the detection signal from the detector 1o is used to adjust the opening degree of the regulating valve 9 via a conductive wire. .

Inside the hopper 2 are the actual ore tank 4 and muddy water discharge pipe 5.
An annular nodule cleaning pipe 11 is installed horizontally below the connection position of the ring, and the pipe wall is provided with a number of jet ports for spouting seawater into and out of the ring, and one end is provided with a hopper. 2. Baby boom washing water intake pipe 1 that opens to the open sea outside
2 is connected to the front end of the connecting pipe 7 for ore lifting, a long ore lifting pipe is used to lift the manganese nodules to the mother ship 13 on the sea using water current and to tow this ore collecting device by the mother ship 18 on the sea. A tube 14 is connected. An ore lifting pump 15 is disposed in the middle of the ore lifting pipe 14, thereby generating an upward flow within the ore lifting pipe 14.

Next, the operation of this ore collector will be explained.

The ore collecting device is supported by a sol on the surface of seabed sediment where manganese nodules are present, and is towed by an ore lifting pipe 14 by a mother ship 18 on the sea, and moves forward at a predetermined speed.

The pressure inside the hopper 2 is lower, for example, by 7 m water column, than the pressure of the seawater outside the hopper 2 by the collecting pump 6 installed in the muddy water discharge pipe 5. Seawater flows through the ore collection duct 4 at a high speed, and the manganese nodules and seabed sediments present on the seabed directly below the opening of the suction head 3 and around it are transported through the ore collection duct 4 by the water flow. It is transported into the hopper 2. The flow rate of the seawater that entered the hopper 2 from the ore collection duct 4 suddenly drops, so manganese nodules fall through the seawater in the hopper due to the relationship between specific gravity and particle size, resulting in fine-grained seabed sediment and extremely small-sized particles. The small manganese nodules are discharged from the muddy water discharge pipe 5 to the outside of the hopper by the action of the X ore collecting pump 6 while suspended in the seawater.

The manganese nodules that have fallen inside the hopper 2 are stored at the bottom of the hopper 2, and the ore pump 15 installed in the middle of the ore lifting pipe 14
Due to the negative pressure generated in the ore lifting pipe 14 and the ore lifting connecting pipe 7, the lumps are sucked out from the ore outlet 2b at the bottom of the hopper 2 into the ore lifting connecting pipe 7, passing through the ore lifting pipe 141 to the sea. The ore is lifted to mother ship 13.

At this time, the concentration of the manganese nodule slurry in the ore lifting pipe 14 is adjusted to the optimum concentration as follows. When the nodule slurry concentration adjustment valve 9 is fully closed, the total lift of the ore lifting pump 15 is set much larger than that of the ore collecting pump 6, so the manganese nodules stored at the bottom of the hopper 2 are The seawater in the hopper is sucked into the ore lifting connection pipe 7, and the flow rate at the nodule discharge port 2b at the bottom of the hopper increases, so many nodules are discharged and the slurry concentration becomes high.

Conversely, when the nodule slurry concentration adjustment valve 9 is fully open, a large amount of seawater flows from the seawater intake pipe 8 into the ore lifting connecting pipe 7 and the ore lifting pipe 1.
4, and the flow velocity at the nodule outlet 2b at the bottom of the hopper 2 slows down, so the amount of manganese nodules supplied to the ore lifting connection pipe decreases, and the nodule slurry concentration becomes extremely small or even zero. Become.

Therefore, by adjusting the opening degree of the nodule slurry concentration adjusting valve 9, the nodule slurry concentration in the ore lifting pipe 14 can be freely adjusted. The opening degree adjustment of this regulating valve 9 is as follows:
In the case of this embodiment, this is automatically carried out based on the detection signal of the nodule slurry concentration detector 10 installed in the ore lifting connecting pipe 7, but the operator on the mother ship 18 lifts the manganese nodules. It is also possible to adjust the valve opening by remote control based on the mine situation, or to set the valve opening accordingly if the seabed topography and manganese nodule abundance in the work area are known in advance.

The seawater pressure outside the hopper is applied to the concave ring-shaped nodules washing pipe 11 provided in the hopper 2 through the nodules washing water intake pipe 12, and the seawater pressure from the outside of the hopper is applied to the inside of the hopper 2 through the numerous jet ports provided on the pipe wall of the washing pipe. Seawater sprays out vigorously. As a result, seafloor sediments (mud) adhering to the manganese nodules falling from the inside and outside of the cleaning pipe toward the bottom of the hopper 2 are washed away, and fine particles of mud are suspended in seawater and removed from the muddy water discharge pipe 5 as much as possible. Discharge into the sea.

The device for adjusting the concentration of manganese nodule slurry in an ore lifting pipe according to the present invention is not limited to the ore collecting device having the arrangement of the ore collecting pump, the nodule cleaning device, and the sealed structure of the hopper shown in the above embodiment, but can also be applied to ore collecting means. It is applicable to an ore collecting device that stores collected manganese nodules in a hopper and supplies them to an ore lifting pipe from the bottom of the hopper.

As described above, according to the present invention, no mechanical means for adjusting the nodule slurry concentration in the ore lifting pipe is provided at the bottom or in the pipe through which the nodules pass, so that wear, failure, etc. can be avoided. A significant reduction effect can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, and FIG. 2 is a plan view thereof. 2... Hopper 8... Suction head (ore collecting means) 7... Connection pipe for ore lifting 8... Seawater intake pipe for nodule slurry concentration adjustment 9... Nodule slurry concentration adjustment valve 10... Nodules slurry concentration detector

Claims (2)

[Claims] (1) A hopper that stores the manganese nodules collected by the ore collection means, and a pipe that is connected to the bottom opening of the hopper and generates an upward water flow inside to lift the manganese nodules at one end and at the other end. a seawater intake pipe that opens into the open sea;
A manganese nodule collector comprising a valve provided in the seawater intake pipe and whose opening degree can be adjusted. (2) A claim characterized in that the manganese nodule lifting pipe is provided with a manganese nodule slurry concentration detection means, and the opening degree of the valve is adjusted based on a detection signal from the detection means. The manganese nodule collector according to item 1.