Carrier substance, method for lifting and mining submarine valuable substances using the same, and lifting and mining device

Abstract

To provide a carrier substance capable of lifting high-density or coarse-grained submarine valuable substances with high lifting efficiency, and a lifting method and a lifting device of submarine valuable substances using the same.SOLUTION: A carrier substance contains water and bentonite clay. A circulatory system duct includes: a downpipe that reaches the seabed from the sea top, and a riser pipe that reaches the sea top from the seabed, and the circulatory system duct is filled with the carrier substance. The carrier substance is circulated by a pump, and submarine valuable substances are mixed with the carrier substance and transported upward together with the carrier substance, and the submarine valuable substances are collected on the sea top.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a carrier substance for transporting and conveying valuable substances, which are undersea mineral resources, to the sea, a lifting method using the same, and a lifting device.

Background Art

[0002] Various techniques have been disclosed as a lifting method and a lifting device for transporting and conveying valuable substances such as undersea mineral resources to the sea. In Patent No. 6570000 (Japanese Unexamined Patent Application Publication No. 2019-120063), an annular pipeline in which a downcomer reaching from the sea to the seabed and a riser reaching from the seabed to the sea are connected on the seabed side and the sea side respectively, a U-shaped pipeline in which a downcomer reaching from the sea to the seabed and a riser reaching from the seabed to the sea are connected on the seabed side, or a double pipe in which the inner pipe is a riser and the outer pipe is a downcomer or vice versa where the inner pipe is a downcomer and the outer pipe is a riser, a carrier substance filled in the annular pipeline, the U-shaped, or the double-pipe pipeline, a pressure pump for circulating the carrier substance, an inlet for carrying in undersea valuable substances provided on the seabed side of the pipeline, and a recovery port for recovering undersea valuable substances provided on the sea side of the pipeline are provided. The carrier substance is a mixture of granular substances with an average particle size of 0.01 mm to 10 mm and a true density of 0.01 to 8 g / cm 3 and a viscous fluid, and a lifting device for undersea valuable substances is disclosed (Claim 1). According to this, since a viscous fluid containing granular substances is used for lifting undersea valuable substances, undersea valuable substances that are granular substances or massive substances with a diameter of 30 mm or more can be lifted with high lifting efficiency.

[0003] Further, in paragraph number 0022 of Patent No. 6570000, it is disclosed that a polymer solution can be used as the viscous fluid, and further, as these polymers, for example, methyl cellulose (MC), sodium carboxymethyl cellulose (CMC-Na), polyethylene oxide (PEO), sodium hydroxyethyl cellulose (HEC-Na), polyvinyl alcohol (PVA), polyacrylamide (PAAM), sodium polyacrylate, starch, gums, pectin, metal alginates, alginate esters, etc. can be used.

[0004] Further, Japanese Patent Application Laid-Open No. 2018-168537 discloses a lifting mining method and a lifting mining device that use a viscous fluid having a viscosity greater than that of seawater as a carrier substance.

[0005] On the other hand, in mud construction methods such as the slurry shield method and the diaphragm wall method, it is known to use excavation mud containing bentonite, CMC, a dispersant, a polymer agent, or the like (Japanese Patent Application Laid-Open No. 2005-36238). These excavation muds have appropriate viscosity and density and exhibit effects such as transporting cuttings, protecting the hole wall, cooling bits, and reducing friction between the drill string and the shaft wall.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Disclosure of the Invention

Problems to be Solved by the Invention

[0007] However, although the carrier substances described in Patent No. 6570000 Gazette and Japanese Patent Application Laid-Open No. 2018-168537 can lift submarine valuable substances with high lifting mining efficiency, they are not yet sufficient, and furthermore, a carrier substance capable of exhibiting high lifting mining efficiency is desired. In addition, conventionally, it has not been known that excavation mud containing bentonite has a function of suppressing the sedimentation of submarine valuable substances in the lifting mining of submarine valuable substances.

[0008] Therefore, an object of the present invention is to provide a carrier substance capable of lifting high-density or coarse-grained submarine valuable substances with high lifting mining efficiency, a lifting mining method for submarine valuable substances using the same, and a lifting mining device. [Means for solving the problem]

[0009] In view of this situation, the present inventors conducted extensive research and discovered that the carrier material of the present invention has a similar composition to conventional drilling mud containing bentonite, but has a high yield stress, and thus has a new attribute of suppressing the settling of seabed valuable materials in the form of granules or lumps in a riser pipe (lifting pipe), which led to the completion of the present invention. That is, the present invention solves the above problems and provides a carrier material that is used for lifting seabed valuable materials and is characterized by containing water and bentonite clay.

[0010] The present invention also provides a method for lifting valuable materials from the seabed, which comprises filling a circulation pipeline having a downcomer pipe reaching the seabed from the sea surface and an upcomer pipe reaching from the seabed to the sea surface with a carrier material, circulating the carrier material with a pump, mixing the valuable materials from the seabed into the carrier material, transporting them upward together with the carrier material, and recovering the valuable materials from the seabed on the sea surface, wherein the carrier material contains water and bentonite clay.

[0011] The present invention also provides an apparatus for lifting seabed valuable materials, comprising: a circulation pipeline having a downcomer pipe reaching the seabed from the sea surface and an upcomer pipe reaching from the seabed to the sea surface; a carrier material filled in the circulation pipeline; a pressure pump for circulating the carrier material; an inlet provided on the seabed side of the pipeline for transporting the seabed valuable materials; and a recovery port provided on the sea surface side of the pipeline for recovering the seabed valuable materials, wherein the carrier material contains water and bentonite clay. Effect of the Invention

[0012] The present invention uses a carrier material containing water and bentonite clay for lifting seabed valuables, which suppresses the sinking of seabed valuables in the form of granules or lumps with a diameter of 30 mm or more, and allows for high ore-lifting efficiency. Also, according to the present invention, a fluid containing water and bentonite clay is filled and circulated in a pipeline as a carrier material, and seabed valuables are taken in and transported in this circulation system, making it possible to lift seabed valuables in the form of coarse granules or lumps. [Brief description of the drawings]

[0013]

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[0014] The carrier material of the present invention is used for lifting valuable seabed materials (hereinafter also referred to as "seabed minerals"), and is a fluid containing water and bentonite clay. For lifting seabed minerals, there is a method of using a lifting device having at least a riser pipe that reaches the sea surface from the seabed where the carrier material is filled. The carrier material is a transport medium for carrying and transporting valuable seabed materials.

[0015] Examples of valuable substances on the seabed include granular or powdered ore X collected from manganese crusts, manganese nodules, cobalt-rich crusts, sulfide deposits (hydrothermal deposits), rare earth mud, or methane hydrates Y existing on the seabed at depths of several hundred to several thousand meters. The granular or powdered ore X is, for example, coarse grains of 0.75 mm or more, or those with a particle density of 3 g / cm 3 or more and having a high density.

[0016] The carrier substance of the present invention is prepared at sea or on land, contains water and bentonite clay, and is preferably a viscous fluid containing water, bentonite clay, and granular bodies. The primary particle size of the bentonite clay is 2 μm or less and is uniformly mixed with water to form muddy water. The blending amount of the bentonite clay is 2 to 50 parts by mass, preferably 5 to 30 parts by mass, based on 100 parts by mass of water. If the blending amount of the bentonite clay is too small, the yield stress becomes small and the effect of suppressing the sedimentation of seabed minerals cannot be obtained. On the other hand, if the blending amount of the bentonite clay is too large, the decrease in fluidity becomes large, which is not preferable. If the bentonite clay is within the above numerical range, the yield stress can be increased and the lifting efficiency can be increased. When preparing the carrier substance, as raw materials, in addition to powdered bentonite clay, those obtained by pulverizing bentonite ore (rock) mined from a mine or pelletized bentonite can be used. In this case, the bentonite is uniformly stirred and mixed with water and pulverized and mixed to the particle size of clay minerals.

[0017] The granular bodies are other than valuable substances on the seabed and are contained in the viscous fluid in advance before use. The granular bodies have an average particle size of 0.01 mm to 10 mm, preferably 0.1 to 8 mm, and a true density of 0.01 to 8 g / cm 3It is so. The average particle size is calculated using a known calculation method obtained from the particle size distribution. Such granular materials may be any of rock-derived, plant / bio-derived, resin materials, and fiber materials, or a mixture thereof. Specifically, examples include expanded beads, glass beads, sands such as silica sand, silt / gravel, wood, and metal powders such as iron powder. The blending amount of the granular material is 10 to 200 parts by weight, preferably 15 to 180 parts by weight, based on 100 parts by weight of water.

[0018] The carrier material of the present invention has a viscosity at 5°C (JIS Z8803; Method for Measuring Viscosity of Liquids) of 1000 mPa·s or more, preferably 1300 mPa·s or more, particularly preferably 2000 mPa·s or more, and even more preferably 3000 mPa·s or more. Also, the plastic viscosity at 5°C is 100 Pa·s or less, and the yield stress at 5°C is 5.0 Pa or more. The yield stress and plastic viscosity can be measured by using rotational and vibrational viscometers in accordance with the method specified in JIS Z8803. The reason for setting the viscosity, yield stress at 5°C is that the seawater temperature is generally stable at around 5°C at depths of several tens of meters or more from the seawater surface, and most of the downcomer and riser are exposed to an environment of 5°C. Note that the upper limit value of the viscosity of the viscous fluid at 5°C is 100,000 mPa·s. If the viscosity is higher than this, it will be close to a solid and it will be practically difficult to pump.

[0019] In addition to bentonite clay and granular materials, the carrier material of the present invention may contain other components. As such other components, those generally referred to as thickeners and water absorbents can be used. For example, methyl cellulose (MC), sodium carboxymethyl cellulose (CMC-Na), polyethylene oxide (PEO), sodium hydroxyethyl cellulose (HEC-Na), polyvinyl alcohol (PVA), polyacrylamide (PAAM), sodium polyacrylate, starch, gums, pectin, metal alginates, alginate esters, etc. can be mentioned. Examples of gums include guar gum, xanthan gum, gellan gum, diutan gum, etc. Examples of metal alginates include sodium alginate, calcium alginate, potassium alginate, etc. These compounds can be used alone or in combination of two or more.

[0020] If the carrier material of the present invention is used for the lifting of submarine valuable substances, granular valuable substances, which are mineral resources, can be transported and carried from the seabed thousands of meters deep to the sea surface with high lifting efficiency, specifically 60% or more, preferably 80% or more. The lifting efficiency refers to the value obtained by dividing the lifting speed by the carrier material flow rate. In the construction field, the discharge volume of a concrete high-pressure pump is about 30 m 3 / hour. If two of them are operated temporarily, with a pipe diameter of 0.5 m, the flow rate is 60 m 3 / hour and the flow rate is 305.6 m / hour. In the case of a lifting efficiency of 80% set on a commercial basis, the sedimentation rate is 60 m / hour. Even if one pump fails, a lifting efficiency of 60% can be ensured.

[0021] The acting forces by which the carrier material of the present invention suppresses the sedimentation of submarine valuable substances include viscous resistance, buoyancy, and effective supporting force. Among these, buoyancy and viscous resistance are borne by the viscous fluid, and the effective supporting force is borne by the granular material. During the flow, viscous resistance is the main factor, and when stopped, the effective supporting force compensates for the deficiency of viscous resistance. Since the carrier material of the present invention is a mixture of water and bentonite clay, it has a yield stress and has a high effect of suppressing the sedimentation of submarine valuable substances.

[0022] The ore lifting method and ore lifting device of the present invention will be described with reference to FIGS. 1 to 3. The ore lifting method of the present invention fills a circulation pipeline system including a downcomer reaching from the sea to the seabed and a riser reaching from the seabed to the sea with a carrier substance, circulates the carrier substance by a pump, mixes seabed minerals into the carrier substance, and conveys the seabed minerals upward in a manner accompanied by the carrier substance, and recovers the seabed minerals on the sea side. In addition, in FIGS. 1 to 3, the description of the granular bodies contained in the carrier substance is omitted.

[0023] The ore lifting device 10 for implementing this method includes an annular pipeline 11 in which a downcomer 1 reaching from the sea to the seabed and a riser 2 reaching from the seabed to the sea are connected on the seabed side and the sea side respectively, a carrier substance 3 filled in the annular pipeline 11, a pressure pump 4 for circulating the carrier substance 3, a carry-in port 5 for carrying in seabed minerals provided on the seabed side of the pipeline 11, and a recovery port 6 for recovering seabed minerals X provided on the sea side of the pipeline 11. In addition, the facilities on the sea side are usually installed on a platform 8 such as an ore lifting ship or an ore lifting float (see FIG. 2).

[0024] The annular (loop) pipeline may be a flexible pipe, for example, a general pipe. Examples of the annular pipeline include a U-shaped pipeline in which the downcomer and the riser are connected on the seabed side, and a double pipe in which the inner pipe is the riser and the outer pipe is the downcomer or vice versa, that is, the inner pipe is the downcomer and the outer pipe is the riser. In addition, the separate riser 2 and downcomer 1 may be integrally welded to each other on the inner surface.

[0025] Since such a carrier substance 3 is a viscous fluid containing water and bentonite clay or a viscous fluid containing water, bentonite clay, and granular materials, it has a high yield stress and flows through the pipe while maintaining the relative positions of the granular submarine minerals to be transported as much as possible. That is, in the circulating state, the carrier substance 3 has fluidity and lifts the granular submarine minerals (sediment substances) with high lifting efficiency. Also, in the static state where the pump is temporarily stopped, the carrier substance 3 suppresses the sedimentation of granular or massive submarine valuable substances (sediment substances) by the action of suppressing the sedimentation of viscous resistance, buoyancy, or viscous resistance, buoyancy, and effective supporting force.

[0026] The annular pipeline 11 has a pump 4 for circulating the carrier substance 3. The pump 4 is a pressure pump, and within the pipeline system, the installation location is not particularly limited. Also, since the pump 4 is installed within the annular pipeline system, even if there is a large height difference between the submarine inlet 5 and the offshore recovery port 6, no load other than the frictional loss of the pipe inner wall occurs on the pump 4, so it is possible to efficiently pressure-pump the carrier substance 3 or the carrier substance 3 containing submarine valuable substances over a long distance.

[0027] The annular pipeline 11 has an inlet 5 for carrying in submarine minerals provided on the submarine side of the pipeline 11. The inlet 5 is a place where granular or massive ores collected from a known ore collector are carried in. As the inlet 5, it is preferable to provide a double door or a rotating door in terms of preventing the leakage of the carrier substance 3 filled in the pipeline. Fig. 3 shows the rotating door 5a installed at the inlet 5, which is a known one (see Japanese Patent Publication No. 6570000).

[0028] Also, the annular pipeline 11 has a recovery port 6 for recovering the submarine minerals X provided on the offshore side of the pipeline 11. A known offshore device 6a as shown in Fig. 2 may be installed at the recovery port 6 (Japanese Patent Publication No. 6570000).

[0029] Next, a method for lifting submarine valuable substances using the lifting device 10 shown in FIGS. 1 to 3 will be described. First, in the lifting device 10 of FIG. 1, the pressure pump 4 is operated. As a result, the carrier substance 3 circulates in the annular pipeline 11. Next, an ore collector (not shown) is operated to collect, for example, granular ore X from a mineral deposit Y at a depth of several thousand meters and carry it into the pipeline 11 through the inlet 5 of the pipeline 11. The granular ore X carried in from the inlet 5 is lifted and transported upward in the riser pipe 2 while being accompanied by the circulating carrier substance 3. Since the collected granular ore X is a coarse-grained or high-density particle and the carrier substance 3 is a viscous fluid containing bentonite clay, it has a high yield stress. It flows through the pipe 11 while maintaining the relative position of the granular ore X as much as possible and is transported and carried with high lifting efficiency without significant sedimentation from the carrier substance 3.

[0030] The ore X transported to the sea is introduced into the separation tank 61 together with the carrier substance 3 from the outlet 6 and separated in the separation tank 61 into the carrier substance 3 containing the ore X and the carrier substance 3 not containing the ore X. The carrier substance 3 containing the ore X is introduced into the pulverizing device 62 and pulverized. The pulverized valuable substance X is further introduced into the ore dressing device 63 and separated into waste minerals X2 and useful minerals X1. On the other hand, the carrier substance 3 not containing the ore X separated in the separation tank 61 is sent to the adjusting device 64, compositionally adjusted, and then sent to the downcomer 1. The compositionally adjusted carrier substance circulates through the downcomer 1 again. The remaining carrier substance recovered by the pulverizing device 62 and the ore dressing device 63 may be returned to the adjusting device 64 or the downcomer 1.

[0031] According to the lifting device and the lifting method of the present invention, since the viscous fluid containing water and bentonite clay, which is the carrier substance, circulates in the annular pipeline, it has a high yield stress and can lift coarse-grained or high-density granular valuable substances with high lifting efficiency. It enables long-distance transportation of about several thousand meters and does not produce waste.

[0032] The present invention is not limited to the above-described embodiment examples and can adopt various modifications. That is, vibration may be applied to the annular pipeline by a known vibration device. Thereby, the flow of the carrier substance can be enhanced. Further, microbubbles may be mixed into the carrier substance circulating in the pipeline from below the pipeline by a known microbubble generator. By this air-lift effect, the upward transportation of the carrier substance is promoted.

[0033] Reference Example 1 (Sedimentation Experiment Part 1) A cylindrical acrylic cylindrical container with a height of 3.6 m and an inner diameter of 100 mm shown in FIG. 4 was filled with a carrier substance, and a spherical ore model simulating submarine valuable substances was dropped from a depth D below the liquid level of the carrier substance in the cylindrical container and on the pipe axis. The relationship between the time required for the ore model to settle and the settling distance was determined.

[0034] <Ore Model A (Sediment Substance)> A complete sphere made of zirconia with a diameter of 12.7 mm and a density of 5.70 g / cm 3 was used. This ore model A has the same size and specific gravity as the ore X of submarine valuable substances. A complete sphere means a sphere whose cross section is nearly a perfect circle.

[0035] <Carrier Substance A> In the container, 9.2 parts by mass of bentonite clay was mixed with 100 parts by mass of tap water to prepare a muddy carrier substance A. The plastic viscosity of the carrier substance A at 25 ° C was 10.2 Pa·s, the yield stress was 22.1 Pa, and the density was 1.14 g / cm 3 It was. The yield stress and plastic viscosity were measured using a rotational viscometer in accordance with JIS Z 8803: Method for Measuring Viscosity of Liquids.

[0036] <Experimental Method A> The operating temperature of carrier material A is 5°C, which corresponds to the seabed temperature. Since the viscosities of carrier material A at 5°C and 25°C are almost the same, it was determined that the influence of temperature is negligible, and the experiment was conducted at room temperature (25°C). First, ore model A was submerged below the liquid surface, and the center of ore model A was maintained at a depth of D = 100 mm below the liquid surface. After waiting for about 20 seconds until the liquid surface became stationary, the ore model was gently released. Subsequently, the elapsed time t and the sedimentation distance l were measured. The results are shown by the symbol ▲ in Figure 5.

[0037] Reference Example 2 (Sedimentation Experiment Part 2) <Carrier Material B> In a container, 9.2 parts by mass of bentonite clay and 19.3 parts by mass of silica sand (No. 6) were mixed with 100 parts by mass of tap water to prepare a muddy carrier material B. The plastic viscosity of carrier material B at 25°C was 56.0 Pa·s, the yield stress was 35.7 Pa, and the density was 1.38 g / cm 3 It was.

[0038] <Experimental Method B> The experiment was conducted in the same manner as <Experimental Method A> in Reference Example 1, except that carrier material B was used instead of carrier material A. That is, in Reference Example 2, the granular material (silica sand No. 6) was further included in the carrier material. In the carrier material, silica sand (No. 6) was used in a uniformly dispersed state. The results are shown by the symbol ■ in Figure 5.

[0039] Reference Example 3 (Sedimentation Experiment Part 3) <Carrier Material C> In a container, 0.5 part by mass of a crosslinked carboxymethyl cellulose (hereinafter referred to as "CMC") was mixed with 100 parts by mass of tap water to prepare carrier material C. The plastic viscosity of carrier material C at 25°C was 0.75 Pa·s, the yield stress was 9.0 Pa, and the density was 1.00 g / cm 3 It was.

[0040] <Experimental Method C> The experiment was conducted in the same manner as <Experimental Method A> of Reference Example 1, except that carrier substance C was used instead of carrier substance A. That is, Reference Example 3 does not contain bentonite clay and serves as a comparative example of the present invention. The results are shown in Fig. 5 by the symbol △.

[0041] Reference Example 4 (Sedimentation Experiment No. 4) <Carrier Substance D> In a container, 0.5 part by mass of CMC and 17.7 parts by mass of silica sand (No. 6) were mixed with 100 parts by mass of tap water to prepare carrier substance D. The plastic viscosity of carrier substance D at 25°C was 1.2 Pa·s, the yield stress was 8.4 Pa, and the density was 1.26 g / cm 3 It was.

[0042] <Experimental Method D> The experiment was conducted in the same manner as <Experimental Method A> of Reference Example 1, except that carrier substance D was used instead of carrier substance A. That is, Reference Example 4 does not contain bentonite clay and serves as a comparative example of the present invention. The results are shown in Fig. 5 by the symbol □.

[0043] In Fig. 5, the mixture of water, bentonite clay, and silica sand (Reference Example 2; symbol ■) was not detected by the measuring instrument (l = 0.2 m) closest to the sedimentation start position even 3 days after the start of sedimentation. Therefore, the position 3 days after the start of sedimentation was estimated to be l = 0.1 m. As shown in Fig. 5 showing the results of Reference Examples 1 to 4, for the zirconia ore model A (fine grains) with a diameter of 12.7 mm and a density of 5.70 g / cm 3 The sedimentation suppression effect of the carrier substance on the zirconia ore model A (fine grains) was significantly superior to that of the mixture of water and bentonite clay (symbol ▲), the mixture of water and CMC (symbol △), or the mixture of water, CMC, and silicon No. 6 (symbol □). In addition, the mixture of water, bentonite clay, and silicon No. 6 (symbol ■) showed a higher sedimentation suppression effect than the mixture of water and bentonite clay (symbol ▲).

[0044] Reference Example 5 (Sedimentation Experiment No. 5) <Experimental Method E> Instead of ore model A, with a diameter of 25.4 mm and a density of 5.97 g / cm 3It was carried out in the same manner as <Experimental Method A> of Reference Example 1, except that a perfect sphere made of zirconia (ore model B) was used. That is, the carrier material of Reference Example 5 is a mixture of water and bentonite clay. The results are shown in Fig. 6 by the symbol ▲.

[0045] Reference Example 6 (Sedimentation Experiment No. 6) <Experimental Method F> Instead of ore model A, a perfect sphere made of zirconia (ore model B) with a diameter of 25.4 mm and a density of 5.97 g / cm 3 It was carried out in the same manner as <Experimental Method B> of Reference Example 2, except that a perfect sphere made of zirconia (ore model B) was used. That is, the carrier material of Reference Example 6 is a mixture of water, bentonite clay, and silica sand No. 6. The results are shown in Fig. 6 by the symbol ■.

[0046] Reference Example 7 (Sedimentation Experiment No. 7) <Experimental Method G> Instead of ore model A, a perfect sphere made of zirconia (ore model B) with a diameter of 25.4 mm and a density of 5.97 g / cm 3 It was carried out in the same manner as <Experimental Method C> of Reference Example 3, except that a perfect sphere made of zirconia (ore model B) was used. That is, the carrier material of Reference Example 7 is a mixture of water and CMC, does not contain bentonite clay, and is a comparative example of the present invention. The results are shown in Fig. 6 by the symbol △.

[0047] Reference Example 8 (Sedimentation Experiment No. 8) <Experimental Method H> Instead of ore model A, a perfect sphere made of zirconia (ore model B) with a diameter of 25.4 mm and a density of 5.97 g / cm 3 It was carried out in the same manner as <Experimental Method D> of Reference Example 4, except that a perfect sphere made of zirconia (ore model B) was used. That is, the carrier material of Reference Example 8 is a mixture of water, CMC, and silica sand No. 6, does not contain bentonite clay, and is a comparative example of the present invention. The results are shown in Fig. 6 by the symbol □.

[0048] As shown in Fig. 6 showing the results of Reference Examples 5 to 8, with a diameter of 25.4 mm and a density of 5.97 g / cm 3The sedimentation inhibition effect of the carrier substance on the zirconia ore model B (medium grain size) was almost the same for the mixture of water and bentonite clay and the mixture of water and CMC. In contrast, for the mixture of water, bentonite clay, and silica sand, it was found that the ore model B took a longer time to sediment in the container and had a high sedimentation inhibition effect.

[0049] Reference Example 9 (Sedimentation Experiment No. 9) <Experimental Method I> Instead of the ore model A, a complete sphere made of alumina (ore model C) with a diameter of 50.8 mm and a density of 3.89 g / cm 3 was used, and the experiment was conducted in the same manner as <Experimental Method A> in Reference Example 1. That is, the carrier substance in Reference Example 9 was a mixture of water and bentonite clay. The results are shown by the symbol ▲ in Fig. 7.

[0050] Reference Example 10 (Sedimentation Experiment No. 10) <Experimental Method J> Instead of the ore model A, a complete sphere made of alumina (ore model C) with a diameter of 50.8 mm and a density of 3.89 g / cm 3 was used, and the experiment was conducted in the same manner as <Experimental Method B> in Reference Example 2. That is, the carrier substance in Reference Example 10 was a mixture of water, bentonite clay, and silica sand No. 6. The results are shown by the symbol ■ in Fig. 7.

[0051] Reference Example 11 (Sedimentation Experiment No. 11) <Experimental Method G> Instead of the ore model A, a complete sphere made of alumina (ore model C) with a diameter of 50.8 mm and a density of 3.89 g / cm 3 was used, and the experiment was conducted in the same manner as <Experimental Method C> in Reference Example 3. That is, the carrier substance in Reference Example 11 was a mixture of water and CMC, without bentonite clay, which is a comparative example of the present invention. The results are shown by the symbol △ in Fig. 7.

[0052] Reference Example 12 (Sedimentation Experiment No. 12) <Experimental Method H> Instead of the ore model A, a complete sphere made of alumina (ore model C) with a diameter of 50.8 mm and a density of 3.89 g / cm 3The experiment was conducted in the same manner as <Experimental Method D> of Reference Example 4, except that a complete sphere made of alumina (ore model C) was used. That is, the carrier substance of Reference Example 12 is a mixture of water, CMC, and silica sand No. 6, and does not contain bentonite clay, which is a comparative example of the present invention. The results are shown by the symbol □ in Fig. 7.

[0053] As shown in Fig. 7 showing the results of Reference Examples 9 to 12, for the alumina ore model C (coarse grains or lumps) with a diameter of 50.8 mm and a density of 3.89 g / cm 3 The sedimentation suppression effect of the carrier substance on the alumina ore model C (coarse grains or lumps) was almost the same for the mixture of water and bentonite clay and the mixture of water and CMC. On the other hand, for the mixture of water, bentonite clay, and silica sand, it was found that the ore model C had a slow sedimentation rate in the container and a high sedimentation suppression effect.

[0054] (Ore lifting experiment) Reference Example 13 (Ore lifting experiment part 1) Using the experimental apparatus 2 shown in Fig. 8, the relationship between the spherical ore model and the ore lifting rate in various carrier substances was determined. The experimental apparatus 2 has an annular pipeline consisting of an upflow pipe 21 with a height of 1.2 m and an inner diameter of 50 mm, a return pipe 22 with one end connected to the upflow pipe and the other end located at the upper opening of the tank, and a feed pipe 25 connecting the tank 23 and the upflow pipe 21. The symbol OM represents the ore model, and CM represents the carrier substance.

[0055] <Ore model D> A complete sphere made of alumina with a diameter of 25.4 mm and a density of 3.86 g / cm 3 was used.

[0056] <Experimental Method I> The tank 23 of the experimental apparatus 2 was filled with the carrier substance A (a mixture of water and bentonite clay) used in Reference Example 1, the pump 24 was operated, and the carrier substance A was circulated at a vertical flow rate of 0.6 cm / s. Subsequently, the ore model D was introduced from the ore model inlet 26, and the lifting speed in the riser 21 was determined. The measurement was performed 4 times. As a result, the lifting speed of the ore model D in the carrier substance A was 0.42 to 0.60 cm / s (the lifting speed of the carrier substance before the introduction of the ore model D was 0.6 cm / s).

[0057] Reference Example 14 (Lifting Experiment Part 2) <Ore Model E> A complete sphere made of PTFE with a diameter of 25.4 mm and a density of 2.18 g / cm 3 was used.

[0058] <Experimental Method J> The experiment was conducted in the same manner as <Experimental Method I> of Reference Example 13, except that the ore model E was used instead of the ore model D. The measurement was performed 3 times. As a result, the lifting speed of the ore model E in the carrier substance A was 0.55 to 0.57 cm / s.

[0059] Reference Example 15 (Lifting Experiment Part 3) <Ore Model F> A complete sphere made of gypsum with a diameter of 25.0 mm and a density of 1.58 g / cm 3 was used.

[0060] <Experimental Method K> The experiment was conducted in the same manner as <Experimental Method I> of Reference Example 13, except that the ore model F was used instead of the ore model D and the carrier substance D (a mixture of water, CMC, and silica sand No. 6) used in Reference Example 4 was used instead of the carrier substance A. The measurement was performed 2 times. As a result, the lifting speed of the ore model F in the carrier substance D was 0.19 to 0.27 cm / s.

[0061] Reference Example 16 (Lifting Experiment Part 4) <Experimental Method L> Except that carrier substance C (a mixture of water and CMC) used in Reference Example 3 was used instead of carrier substance A, the procedure was the same as <Experimental Method I> of Reference Example 13. As a result, the ore model D in carrier substance C could not be lifted, and the lifting rate could not be measured. In addition, even when the procedure was carried out for ore models E and F instead of ore model D, similarly, they could not be lifted, and the lifting rate could not be measured.

[0062] From the results of Reference Examples 13 and 16, for ore models with a density of 2.18 g / cm 3 ~3.86 g / cm 3 carrier substance A (a mixture of water and bentonite clay) could obtain a high lifting efficiency with almost suppressed sedimentation, while carrier substance C (a mixture of water and CMC) could not suppress sedimentation and could not be lifted.

[0063] From the results of Reference Examples 14 to 15, for ore models with a density of 1.58 g / cm 3 ~2.18 g / cm 3 carrier substance D (a mixture of water, CMC, and silica sand No. 6) had a lower lifting rate compared to carrier substance A (a mixture of water and bentonite clay) that did not contain granular material (silica sand No. 6), even though it contained granular material (silica sand No. 6).

[0064] From the results of Reference Examples 1 to 16, when a mixture of water and bentonite clay was used as the carrier substance, it was found that the carrier substance had a yield stress and the effect of suppressing sedimentation was higher than that of the conventional carrier substance containing water and CMC. In addition, when a mixture of water, bentonite clay, and silica sand No. 6 was used as the carrier substance, a higher sedimentation suppression effect was obtained compared to the mixture of water and bentonite clay that did not contain silica sand No. 6.

Industrial Applicability

[0065] According to the present invention, granular valuable substances as mineral resources can be efficiently transported and carried from the seabed thousands of meters deep to the sea surface. Regarding the lift height, in the construction field, the actual pumping performance of fresh concrete using a 4-inch pipe without relay points is 90 m 3With a high-pressure pumping of 12 MPa, it has achieved a horizontal distance of 900 m and a vertical distance of 200 m. For the annular pipeline of the present invention, it can be easily pumped even with a head exceeding 1000 m vertically.

Explanation of Reference Signs

[0066] 1 Downcomer 2 Upcomer 3 Carrier substance 4 Pump 5 Inlet 6 Recovery port 10 Ore lifting device 11 Annular pipeline X Granular ore (submarine valuable substance) Y Ore deposit

Claims

1. It is used for the lifting mining of submarine valuable substances, contains water and bentonite clay, and the blending amount of the bentonite clay is 5 to 30 parts by mass with respect to 100 parts by mass of water, and has a plastic viscosity of 100 Pa·s or less at 5°C and a yield stress of 5.0 Pa or more at 5°C. A carrier substance characterized by this.

2. Furthermore, the carrier material according to claim 1, comprising granular bodies having an average particle diameter of 0.01 mm to 10 mm and a true density of 0.01 to 8 g / cm ３ wherein the granular bodies are other than the submarine valuable substances and are premixed before use.

3. The blending amount of the granular material is 10 to 200 parts by mass with respect to 100 parts by mass of water. The carrier substance according to Claim 2, characterized by this.

4. The carrier substance according to any one of Claims 1 to 3, characterized by being a viscous fluid.

5. A method for lifting and mining submarine valuable substances, which fills a circulation pipeline system equipped with a downcomer reaching from the sea to the seabed and a riser reaching from the seabed to the sea with a carrier substance, circulates the carrier substance by a pump, mixes the submarine valuable substances into the carrier substance, and transports them upward by accompanying the carrier substance, and recovers the submarine valuable substances on the sea side. The carrier substance contains water and bentonite clay, and the blending amount of the bentonite clay is 5 to 30 parts by mass with respect to 100 parts by mass of water, and has a plastic viscosity of 100 Pa·s or less at 5°C and a yield stress of 5.0 Pa or more at 5°C. A method for lifting and mining submarine valuable substances, characterized by this.

6. Furthermore, the granular material has an average particle size of 0.01 mm to 10 mm and a true density of 0.01 to 8 g / cm ３ and the granular material is other than the submarine valuable substance and is premixed before use. The method for lifting and mining submarine valuable substances according to claim 5, characterized in that it comprises the granular material.

7. A downcomer reaching from the sea to the seabed, A circulation pipeline system equipped with a riser reaching from the seabed to the sea, A carrier substance filled in the circulation pipeline system, A pressure pump for circulating the carrier substance, A loading port for loading submarine valuable substances provided on the seabed side of the pipeline, A recovery port for recovering submarine valuable substances provided on the sea side of the pipeline, and has, The carrier substance contains water and bentonite clay, and the blending amount of the bentonite clay is 5 to 30 parts by mass with respect to 100 parts by mass of water, and has a plastic viscosity of 100 Pa·s or less at 5°C and a yield stress of 5.0 Pa or more at 5°C. A device for lifting and mining submarine valuable substances, characterized by this.

8. Furthermore, the average particle size is 0.01 mm to 10 mm, and the true density is 0.01 to 8 g / cm ３ The apparatus for lifting and mining submarine valuable substances according to claim 7, further comprising granular bodies, wherein the granular bodies are other than submarine valuable substances and are premixed before use.

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