Arrangement and method for extracting mineral resources from a waterbed

Description

[0001] The invention relates to an arrangement for extracting mineral resources from a body of water, comprising a watercraft for traveling on the body of water and at least one extraction unit which is designed to extract mineral resources from the body of water and is connected to the watercraft via at least one conveying line, wherein extracted mineral resources can be conveyed to the watercraft as an extraction fluid via a first conveying line, according to the preamble of claim 1.

[0002] The invention further relates to a method for extracting mineral resources from a body of water using a watercraft for traveling on the body of water and at least one extraction unit which is designed to extract mineral resources from the body of water and is connected to the watercraft via at least one conveying line, wherein extracted mineral resources are conveyed to the watercraft as an extraction fluid via a first conveying line, according to the preamble of claim 14.

[0003] EP 3 805 465 A1 discloses an underwater mining device for extracting raw materials from the bottom of a body of water. This device comprises an mining unit that is guided on a base frame so that it can be displaced horizontally to assume various mining positions.

[0004] WO 2015 / 178854 A1 and WO 2015 / 178853 A1 also disclose underwater mining systems. These systems utilize multiple mobile mining units, from which excavated soil is transported to floating containers located underwater between the mining units and a supply vessel.

[0005] The extraction of mineral resources from the bottom of a body of water is energy-intensive and associated with environmental pollution.

[0006] The invention is based on the Task The aim is to specify an arrangement and a procedure by which mineral resources on the bottom of a body of water can be extracted in an economical and energy-efficient manner and thus in a particularly environmentally friendly manner.

[0007] The object is achieved according to the invention by an arrangement having the features of claim 1 and a method having the features of claim 14. Preferred embodiments of the invention are specified in the dependent claims.

[0008] The arrangement according to the invention is characterized in that at least one power generation unit is arranged on the watercraft, which is designed to convert heat of the mining fluid into electrical current.

[0009] The invention is based on the discovery that certain mineral resources occur more frequently in geologically active zones, such as geologically active fault lines or thrust lines of continental plates or in the vicinity of volcanoes. A further discovery of the invention is that, due to geothermal effects, mining fluids extracted in such zones during mineral extraction can have a temperature that can be significantly higher than the ambient temperature at a body of water's surface.

[0010] One aspect of the invention is to utilize the heat of such a mining fluid extracted from the waterbed by means of a power generation unit, which converts the heat of the mining fluid into electrical power. According to the invention, this allows a significant amount of electrical power to be saved or replaced, which would otherwise have to be generated on the vessel. Since supply vessels usually have marine engines powered by heavy fuel oil or diesel, energy generation from the heat of the mining fluid is not only economical but also environmentally friendly. This significantly reduces the CO2 footprint of mineral extraction. In addition, mineral extraction often takes place in sensitive areas, so that

[0011] Reducing exhaust gases from combustion engines on site also has a positive impact on the immediate environment.

[0012] It is further preferred that the power generation unit comprises a thermal-electric generator or at least one Peltier element, which can convert temperature differences directly into electrical current via semiconductor components.

[0013] In principle, heat can be converted into electrical power using any suitable power generation unit. According to one embodiment of the invention, it is particularly preferred that the power generation unit is designed as a circulation system with an evaporation medium. In particular, an ORC system can be provided. With an ORC principle (Organic Rankine Cycle), electrical power can also be generated from media or fluids whose temperature level is only relatively slightly above the ambient temperature level. An ORC system basically functions like a conventional cogeneration plant, with heat from the decomposition fluid being transferred to an evaporation medium via a heat exchange process. However, the evaporation medium used is not water, but a suitable organic substance, for example based on hydrocarbons or silicone oil, with a relatively low boiling or evaporation point.The steam thus generated is expanded through a turbine, which drives a generator to generate electricity. The expanded steam can, if necessary, be recirculated via a condenser after cooling to ambient temperature. Economical yield can be achieved even with mining fluids at temperatures starting at approximately 50°C, especially between 60 and 90°C or higher.

[0014] Depending on the consistency of the decomposition fluid, it can be fed directly to the ORC system via a heat exchanger. According to one embodiment of the invention, it is particularly expedient for a pre-heat exchanger to be installed upstream of the power generation unit, which transfers heat from the decomposition fluid to a heat exchange medium, which can then be passed on to the power generation unit. Particularly in the case of abrasive solids in the decomposition fluid, it may be advisable not to feed this abrasive decomposition fluid directly to the power generation unit, especially to a sensitive ORC system, but rather to first transfer the heat to a heat exchange medium, such as water or another liquid, and then to feed this heat exchange medium to the power generation unit and in particular to the ORC system.

[0015] Alternatively, the power generation unit can also be operated with a Clausius-Rankine cycle, for example, based on organic substances such as isopentane, or with a Kalina cycle. In a Kalina cycle, a liquid medium based on ammonia and water is used as the evaporation medium, with a lower evaporation point than water. The steam generated by heat absorption drives a turbine to generate electricity.

[0016] For efficient extraction of mineral resources, according to a further development of the invention, it is preferred that at least one separator unit be arranged on the watercraft, with which solid components and / or a carrier liquid can be separated from the mining fluid. The separator unit can in principle be any suitable device for solid-liquid separation. The mineral resources can be present both in the solid components and as dissolved metals or minerals in the carrier liquid. In principle, additional separation units can be provided on the watercraft in order to separate or separate the usable substances from the mining fluid to the greatest possible extent.

[0017] Depending on the composition of the decomposition fluid, it may be advantageous for the at least one separator unit to be located upstream and / or downstream of the power generation unit. Particularly effective utilization of the heat of the decomposition fluid can be achieved by only placing the separator unit downstream of the power generation unit. In certain cases, however, it may be advantageous to place a separator unit upstream of the power generation unit to ensure good flow through the heat exchanger of the power generation unit, particularly if a preheat exchanger is not required.

[0018] It is also particularly expedient for the at least one separator unit to comprise a filter device, a decanter, a centrifuge, and / or a screening device. This device allows for particularly good solid-liquid separation. Particularly in the case of mineral extraction on the bottom of a body of water, the carrier liquid can be the ambient water. Depending on the type of body of water, this can be freshwater or saltwater.

[0019] For particularly efficient energy utilization, it is particularly advantageous that the decomposition fluid or carrier fluid can be fed to the power generation unit. This arrangement, in particular, eliminates the need for a preheat exchanger as described above.

[0020] The valuable or useful materials separated or extracted from the mining fluid can be transported by the separator unit to suitable tanks or storage facilities. In certain cases, the mining fluid can be recycled in its entirety. For larger proportions of non-recyclable components, a further development of the invention provides for at least one return line to be provided, allowing at least a portion of the mining fluid to be conveyed from the watercraft back into the body of water. The return line is preferably designed to return the recycled materials to the mining area of ​​the waterbed, ideally close to the mining site.

[0021] In a particularly simple embodiment, according to a variant of the invention, the extraction unit can be designed to extract free-flowing, particularly sludge-like, mineral resources. The mineral resources can be deposited in sludge-like layers on the bottom of the water body.

[0022] For use on a solid body of water, according to a further embodiment of the invention, it is advantageous for the mining unit to have at least one removal tool with which solid base material of the body of water can be removed and crushed. The removed base material is mixed with a carrier liquid and removed as a mining fluid. The removal tool can be, in particular, a drill, a milling wheel, or a rotating milling chain. In particular, several driven removal tools can also be used, which are in particular equipped with removal teeth.

[0023] In principle, the mining unit can be lowered from the watercraft to the waterbed using a suitable lifting device, in particular at least one cable winch. At the point at which the mining unit is lowered, it can then mine material from the waterbed. According to a further development of the invention, it is particularly preferred that the mining unit is designed with at least one of its own drive for moving along the waterbed. The structural unit can be designed with a crawler track and / or a propulsion propeller and / or propulsion nozzles for moving in the water along the waterbed. This enables targeted movement of the mining unit. A so-called umbilical can be provided, through which the mining unit is connected to the watercraft for control purposes, in particular to an operating station, and for power supply.A delivery and / or return line can also be integrated into the umbilical, but they can also be designed as separate lines.

[0024] For efficient removal of the extracted mineral resources, according to one embodiment of the invention, it is preferred that at least one conveying pump be arranged on the mining unit and / or the watercraft. Conveying the flowable mining fluid by means of one or more conveying pumps enables economical material transport.

[0025] The invention further relates to a method for extracting mineral resources from a body of water, using an arrangement according to one of claims 1 to 13, wherein the method is characterized in that at least one power generation unit is arranged on the watercraft, which converts heat from the extraction fluid into electrical current. In particular, an arrangement as described above can be used to carry out the method. The advantages described above can be achieved in this way.

[0026] A preferred variant of the method according to the invention consists in carrying out mining in a geologically active zone in which an elevated temperature exists. Such geologically active zones represent, in particular, fault lines or thrust lines along the continental plates. For example, on the floor of the Red Sea, along trenches at the thrust lines between the African continental plate and the Eurasian continental plate, there are geothermally heated deposits of mineral resources with a temperature between 50°C and 90°C, in particular in the range of 68-70°C. Such deposits on a body of water can be mined using the method according to the invention, generating a useful amount of electrical energy.

[0027] According to a further variant of the method according to the invention, it is particularly advantageous for metals and / or minerals to be separated from the mining fluid as mineral resources. A separator unit can be used for this purpose, which separates solids from liquids. The mineral resources can be present as solids and / or as dissolved substances in the liquid.

[0028] The invention is explained in more detail below with reference to a preferred embodiment, which is shown schematically in the accompanying drawing.

[0029] The single figure schematically shows an arrangement 10 according to the invention with a watercraft 20, in particular a supply vessel, which floats on a body of water 3. A schematically illustrated mining unit 30 is lowered from the watercraft 20 onto a body of water bed 5 by means of a cable winch 22 via a cable or an umbilical 23. The mining unit 30 is designed to mine or extract base material from the body of water bed 5. The base material can comprise mineral resources, in particular metals or minerals. The mineral resources are crushed, if necessary, and pumped from the mining unit 30 upwards to the watercraft 20 via a first conveying line 32 as a flowable mining fluid 18. The pump can be directly electrically driven, but it is also possible to drive a hydraulic pump with an electric motor, which drives the pump via a hydraulic line and a hydraulic motor.

[0030] In a generally known manner, the components considered useful or valuable materials can be separated from the mining fluid 18 via a solid-liquid separation device and forwarded to a receptacle 26, such as a tank. The separation or separator unit for solid-liquid separation is not shown in detail. Unusable carrier fluid with residual solid components can be returned to the body of water 3 via a return line 34, and in particular to the area of ​​the mining site at the mining unit 30.

[0031] In the arrangement 10 according to the invention, a power generation unit 40 is arranged on the watercraft 20, which is designed to convert heat from the decomposition fluid 18 into electrical power. The power generation unit 40 is, in particular, an ORC system in which an organic vaporizing agent is vaporized by the elevated temperature of the decomposition fluid 18, which is greater than an ambient temperature of the watercraft 20. The steam thus generated can be used to operate a turbine, which drives a generator for generating electricity. After expansion and condensation, the vaporizing agent can be recirculated with cooling to the ambient temperature. A further heat exchanger can be provided to cool the vaporizing agent.

[0032] Mining fluids 18 with such an elevated temperature, which can be in the range between 50°C and 90°C, can occur particularly in geologically active zones and in the area of ​​volcanoes.

[0033] The electrical energy thus generated can be used on the watercraft 20, for example to operate the cable winch 22 or pumps for conveying the mining fluid 18. This relieves the load on the ship's fuel-powered units, which has a positive effect on energy consumption and environmental pollution.

Claims

1. Arrangement for extracting soil resources from a bed of a body of water (5), having - a watercraft (20) for travelling on the body of water (3) and - at least one extraction unit (30) configured for extracting soil resources on the bed of a body of water (5), which unit is connected to the watercraft (20) via at least one conveying line (32, 34), wherein extracted soil resources can be conveyed as an extraction fluid (18) to the watercraft (20) via a first conveying line (32), characterized in that at least one power generation unit (40) is arranged on the watercraft (20), which power generation unit is configured to convert the heat of the extraction fluid (18) into electric current.

2. Arrangement according to claim 1, characterized in that the power generation unit (40) is configured as a closed-circuit system with an evaporation medium.

3. Arrangement according to claim 1, characterized in that the power generation unit (40) is configured as a thermoelectric generator or has at least one Peltier element.

4. Arrangement according to any one of claims 1 to 3, characterized in that a pre-heat exchanger is connected upstream of the power generation unit (40), which transfers heat from the extraction fluid (18) to a heat exchange medium, which can then be passed on to the power generation unit (40).

5. Arrangement according to any one of claims 1 to 4, characterized in that at least one separator unit is arranged on the watercraft (20), with which solid components and / or a carrier liquid can be separated from the extraction fluid (18).

6. Arrangement according to claim 5, characterized in that the at least one separator unit is connected upstream and / or downstream of the power generation unit (40)7. Arrangement according to claim 5 or 6, characterized in that the at least one separator unit comprises a filter device, a decanter, a centrifuge and / or a strainer device.

8. Arrangement according to any one of claims 1 to 7, characterized in that the extraction fluid (18) or the carrier liquid can be supplied to the power generation unit (40).

9. Arrangement according to any one of claims 1 to 8, characterized in that at least one return line (34) is provided, with which at least a part of the extraction fluid (18) can be conducted from the watercraft (20) back again into the body of water (3).

10. Arrangement according to any one of claims 1 to 9, characterized in that the extraction unit (30) is configured for sucking off flowable, in particular muddy, soil resources.

11. Arrangement according to any one of claims 1 to 10, characterized in that the extraction unit (30) has at least one stripping tool, with which solid ground material of the bed of a body of water (5) can be stripped and crushed, wherein the extracted ground material is mixed with a carrier liquid and is discharged as extraction fluid (18).

12. Arrangement according to any one of claims 1 to 11, characterized in that the extraction unit (30) is configured with at least one drive of its own for moving along the bed of a body of water (5).

13. Arrangement according to any one of claims 1 to 12, characterized in that at least one conveying pump is arranged on the extraction unit (40) and / or the watercraft (20).

14. Method for extracting soil resources from a bed of a body of water, in particular having an arrangement (10) according to any one of claims 1 to 13, having - a watercraft (20) for travelling on the body of water (3) and - at least one extraction unit (30) configured for extracting soil resources on the bed of a body of water (5), which unit is connected to the watercraft (20) via at least one conveying line (32, 34), wherein extracted soil resources are conveyed as an extraction fluid (18) to the watercraft (20) via a first conveying line (32), characterized in that at least one power generation unit (40) is arranged on the watercraft (20) which power generation unit converts the heat of the extraction fluid (18) into electric current.

15. Method according to claim 14, characterized in that extraction is performed in a geologically active zone in which there is an increased temperature.

16. Method according to claim 14 or 15, characterized in that metals and / or minerals are separated from the extraction fluid (18) as soil resources.