Method for the systematic selective extraction of solid mineral raw materials by means of directional drilling technology

Abstract

According to the invention, a method for the systematic selective extraction of solid mineral raw materials by means of a drilling device using directional drilling technology is provided, in which method, in a first step, an extraction drilling unit (19) drills through a rock layer (5) with an orientation drilling portion (6) and is thereby guided selectively and precisely into an excavation zone, in a second step, a 3D drilling grid (7) composed of a plurality of extraction drilling portions (8) is placed at the end of the orientation drilling portion (6), and, in a third step, extraction drilling portions (8) routed parallel to one another three-dimensionally are drilled, wherein a spacing of at most 45 cm is arranged between the final outside diameters of two adjacent extraction drilling portions (8), measured in the common normal direction of the two adjacent borehole axis portions, and wherein in each case one extraction drilling portion (8) after the other is drilled and, after the completion of an extraction drilling portion (8), this extraction drilling portion (8), together with the associated orientation drilling segment (6c), is secured.

Description

[0001] Method for the systematic selective extraction of solid mineral raw materials using directional drilling technology

[0002] The invention relates to a method for the systematic selective extraction of solid mineral raw materials using a drilling rig with directional drilling technology.

[0003] The invention further relates to a system for carrying out the method according to the invention.

[0004] The invention deals with the systematic,

[0005] (Highly) selective extraction and processing of deposits of solid mineral raw materials in open-pit or underground mining. In conventional mining of solid mineral raw materials, large to very large machines are predominantly used, both in open-pit and underground mining. The goal is to make the extraction operations as efficient and the costs per ton of total output as low as possible.

[0006] The sheer dimensions of these machines mean that the loosening, extraction, loading, and removal of valuable mineral rock can only be carried out over large-scale mining areas. The resulting consequence is that the selectivity in extraction—i.e., the separate extraction and separation of high-quality, well-mineralized valuable mineral rock from unmarketable, poorly or even completely unmineralized rock—is severely limited.

[0007] In conventional underground mining, for example, selective, quality-controlled extraction of valuable mineral rock is usually carried out on a mining cross-section of 4m by 4m or around 16m 2 . The selectivity is very low over long distances.

[0008] In conventional underground mining, therefore, there is very often an unnecessary mixing of high-quality valuable mineral with poorly or slightly mineralized valuable mineral rock, i.e. rock mineralized below the desired mining quality level or below the planned minimum grade (the "cut-off grade") and / or completely unmineralized waste rock. The total output mined in this way from a mining cross-section or mining block therefore contains a non-negligible amount of poorly or completely unmineralized rock, so-called waste rock.

[0009] This waste rock, which is mixed into the total production quantity due to mining, must subsequently be extracted from the respective mining area to the surface and thus not only burdens the operating performance and costs of extraction, but also, as a further consequence, all downstream processes such as crushing, processing, refining and disposal of process residues with unnecessary, worthless rock material.

[0010] And it is precisely these processing and refining residues that have to be disposed of and which have to be separated from the valuable mineral in complex and cost-intensive processes that essentially also contain the rock material that was previously mined underground with little or no mineralization.

[0011] These unnecessarily mined waste rock quantities place an unnecessarily high burden on all downstream processes and require unnecessarily large plant dimensions.

[0012] In addition, avoidable amounts of machine and plant operating hours, water, energy and treatment chemicals are consumed, and unnecessary amounts of avoidable emissions, process residues and other environmental pollution are caused.

[0013] It is therefore an object of the invention to reduce the above-mentioned disadvantages of conventional underground mining, to even eliminate them in certain areas or at least to minimize them to the technically absolutely smallest extent.

[0014] According to the invention, a method of the type mentioned at the outset is provided in which an extraction drilling unit, in a first step, drills through a rock layer with an alignment drilling section and is selectively and precisely guided into an extraction zone, in a second step a 3D drilling grid comprising a plurality of extraction drilling sections is created at the end of the alignment drilling section and, in a third step, three-dimensionally parallel extraction drilling sections are drilled, with a maximum distance of 45 cm being arranged between the final outer diameters of two adjacent extraction drilling sections, measured in the common normal direction of the two adjacent borehole axis sections, and with one extraction drilling section being drilled after the other and, after the completion of an extraction drilling section, this extraction drilling section is secured together with the associated alignment drilling segment.The purpose of securing the rock is to restore sufficient rock stability and is preferably achieved by completely backfilling the extraction drilling section including the associated alignment drilling segment by means of (qualified) cementing.

[0015] In the drilling method according to the invention, at least two borehole sections are provided. One section is for the preparation and preparation of the extraction (the alignment drilling section), in which a drilling grid consisting of several extraction drilling sections is created, and the other section is for the extraction of the valuable mineral rock (the extraction drilling section), in which the extraction boreholes are drilled.

[0016] As a rule, the overburden lies between the surface and the planned mining section. Therefore, it is preferred that, prior to the first step, an overburden layer is drilled through with an exploratory drilling section, to which the orientation drilling section connects, as described above. The exploratory drilling section, which starts at the surface or underground, preferably drills through or penetrates the overburden in any direction and serves to explore the deposits, i.e., to approach the deposits to be mined. In this case, three borehole sections are therefore provided.

[0017] All two or three borehole sections are passed through in the order listed in order to reach the mining block to be selectively extracted from the borehole starting point, the borehole head, which can be located either on the surface or underground.

[0018] If necessary, after drilling through the overburden, a specific part of the deposit or mining section is developed, i.e., prepared and prepared for mining, via the alignment drilling section. This alignment drilling section is preferably divided into at least two segments. The first segment leads in the direction of the mining drilling sections. The second segment represents the mining device and connects the first alignment segment directly to the drilling grid of the mining drilling sections.

[0019] The orientation drilling section preferably comprises three segments, the first segment directing itself in the direction of the extraction drilling sections and then being divided into at least two second segments. As explained above, the first segment ensures the main alignment in the planned extraction drilling direction, which preferably points in the dip direction of the main mineralization, while the second segments each lead specifically into individual mining sections to be selectively extracted. The second segments are followed by several third segments which form the 3D drilling grid and thus prepare the highly selective extraction drilling sections. In the extraction drilling section, the valuable mineral rock is extracted systematically and highly selectively within the prepared mining section using an extraction drilling unit.

[0020] This occurs in more or less dense packings, i.e., through more or less densely arranged and more or less completely filled 3D grids of precisely parallel extraction drilling sections of any length, orientation, and course. The extracted material can then be transported to the surface as cuttings via drilling fluid for processing.

[0021] Within the drilling grid, the three-dimensional, precisely parallel extraction drilling sections are preferably produced at very close intervals. Therefore, it is preferred that the distance between the final outer diameters of two adjacent extraction drilling sections be a maximum of approximately 40 cm, more preferably a maximum of approximately 30 cm. The distance between the final outer diameters of two adjacent extraction drilling sections is measured in the common normal direction of the two adjacent borehole axis sections.

[0022] Preferably, after completion of the alignment drilling section, the alignment drilling section is secured. This improves the stability of the rock.

[0023] Preferably, after completion of the exploratory drilling section, the exploratory drilling section is secured. This step also improves the stability of the rock.

[0024] Furthermore, it is preferably provided that after completion of the exploratory drilling section and the alignment drilling section, both the exploratory drilling section and the alignment drilling section are preferably secured.

[0025] Poorly or only slightly mineralized, i.e., below a certain cut-off grade, or even unmineralized (waste rock) zones are preferably selectively excluded, bypassed, and thus not mined, or drilled through or penetrated only with the smallest possible borehole cross-section. This particularly reduces the amount of waste rock extracted and thus increases the environmental and energy-relevant efficiency of the process.

[0026] In the same way, geological and / or hydrogeological problem zones and / or known or unknown natural or artificially created cavities can be avoided or bypassed.

[0027] The present process allows a mining cross-sectional area of ​​approximately 2 . The selectivity of the process of the present invention is therefore 16 times higher, more detailed and more precise than conventional processes, which require a mining cross-sectional area of ​​around 16m2 is applied. The proportion of waste rock in the total output is thus reduced to a minimum during underground mining. This results in a significantly higher valuable mineral content in the total output. At the same time, all downstream processes are relieved by a significantly lower amount of waste rock.

[0028] Securing, i.e. the rock mechanical stabilization of the borehole and the immediately adjacent rock is essential to prevent the boreholes from drifting, for example, into open or poorly stabilized neighboring boreholes. This danger exists particularly when drilling extraction sections, which are drilled very close together. In addition, the stabilization of completed boreholes is also necessary to ensure the overall stability of the mining area. Collapsing boreholes would make mining in the immediate mining area impossible. The invention therefore provides for this extraction section to be secured immediately after completion.Depending on the prevailing rock conditions, it is also planned that (immediately) after completion of the exploration and alignment drilling sections, these drilling sections will also be secured.

[0029] The following four stabilisation measures are preferably planned to secure the drilling sections:

[0030] 1 . The inventive arrangement of the extraction drilling sections,

[0031] 2 . The qualified securing of each borehole,

[0032] 3 . The production of the final outer diameter of at least one extraction bore section by means of a borehole enlargement process, and

[0033] 4 . The "Pad Drilling" method .

[0034] Ad 1 . Geotechnical stability studies, which take into account the prevailing rock conditions, the planned deposit recovery, the selected drilling technology and other environmental protection requirements, define the minimum permissible borehole spacing and the maximum permissible borehole diameters for each deposit and each extraction section.

[0035] The arrangement of the extraction drilling sections according to the invention is carried out accordingly, for example 1a) in the 3D standard drilling grid with constant borehole spacing and constant diameter, or deviating from this 1b) in any variation and mixture of different spacings and diameters for non-standard 3D grids, where 1c) the bundles of parallel extraction drilling sections can have any length and take any direction, from vertical, inclined (steep or flat) to horizontal, but also slightly curved in all directions, and 1d) the drilling sequence or sequencing of the boreholes in the 3D grid makes a significant contribution to rock stability.

[0036] According to the invention, it is therefore provided that one extraction drilling section is drilled after the other. Preferably, a first extraction drilling section is drilled first, followed by a second extraction drilling section located a certain sequencing distance from the first extraction drilling section. In a 3D standard drilling grid, this sequencing distance is measured, for example, between the final outer diameters of the first extraction drilling section and the second extraction drilling section, specifically in the common normal direction of the two adjacent borehole axis sections, and this is preferably larger than the final outer diameter of the first or the second extraction drilling section. The rock that makes up the sequencing distance can consist either of unpitted rock or of rock that has been largely stabilized by qualified borehole backfilling.Sequencing ensures the stability of the rock during the drilling process. (le) The vertical drilling sequence of the boreholes, or borehole sections, and borehole bundles can follow any order, but must comply with the requirements of the stability study. It is most likely, however, that it begins at the highest extraction point and is sequenced downwards. The closer the borehole spacing, the higher the deposit recovery, which can be up to 90% with slight overlap of the extraction drilling sections.

[0037] Through the arrangement and sequence of the boreholes and their immediate securing, a sufficient degree of rock stability can be maintained between the borehole sections at all times.

[0038] Ad 2 .) The qualified securing of each borehole is considered standard to ensure sufficient rock stability both for the drilling of each individual borehole and for the overall process.

[0039] 2a ) The complete backfilling of an extraction drilling section including the associated alignment drilling segment by qualified cementing is considered a standard procedure to ensure or improve rock stability for precisely parallel drilling with close spacing.

[0040] Complete backfilling or cementing takes place immediately after completion of the extraction drilling section and absorbs as much waste rock (in the form of separated processing residues of any grain size) previously extracted in the boreholes as possible, thereby minimizing the requirements for stockpiling, i.e., the disposal of waste rock and processing residues at the surface. The requirements for the qualified strength of the borehole backfill (cementing) are derived from the results of the geotechnical stability study.

[0041] 2b) Depending on the existing rock strength and the required environmental protection, work may also be carried out without backfilling the boreholes, i.e. with open boreholes, provided that the geotechnical stability study and other environmental protection requirements allow this.

[0042] 2c ) In demanding rock conditions and / or for special requirements, a simple borehole backfill can be improved as follows : by

[0043] 2cl ) use of fibre-reinforced cementing and / or 2c2 ) additional casing ( i.e. also filled casing);

[0044] 2d) In challenging rock conditions, including natural or artificial cavities or rock loosening, and in order to maximize the recovery of the reservoir, rock stabilization may also be achieved by partially or completely casing the borehole, which may be carried out either with or without casing recovery.

[0045] Preferably, immediately after completion of an extraction drilling section, this extraction drilling section, including the associated alignment drilling segment, is completely filled by qualified cementing.

[0046] Ad 3 .) It is preferably provided that the final outer diameter of at least one extraction drilling section is produced by means of a borehole enlargement process. A borehole enlargement process is beneficial for the method of the invention and enables two preferred advantages:

[0047] 3a ) A gradual enlargement of the borehole diameter makes it possible to maintain a larger borehole spacing in a first drilling phase using a smaller borehole diameter while still maintaining good rock stability and achieving good positional accuracy, and to produce a final larger outer diameter with a closer spacing only in a subsequent second drilling phase, which uses the smaller, first borehole diameter as a guide; and

[0048] 3b) a stepwise borehole enlargement increases the selectivity of the process according to the invention by penetrating small dead zones, which cannot be avoided, with the smallest borehole diameter and by extracting deposit areas lying after the dead zone.

[0049] Ad 4 .) The preferred "pad drilling" method in combination with the semi-mobility of the drilling equipment used is very beneficial for the method of the invention and enables two preferred advantages:

[0050] 4a ) on the one hand, the sufficient hardening of the borehole backfill for rock stabilisation before the start of the next drilling in the immediate vicinity, and

[0051] 4b ) the provision of the necessary drilling capacity for a planned annual production volume .

[0052] For mining purposes, a deposit is usually divided into several mining sections, within each of which homogeneous geological and geotechnical conditions exist and which satisfy the selected extraction method and the technology used.

[0053] It is therefore preferably provided that the deposit is divided into essentially homogeneous mining sections. This preferably takes place before the first step of the method according to the invention. Subsequently, a so-called "pad drilling" process is applied within each mining section.

[0054] For this purpose, prior to the first step of the method according to the invention, the mining planning divides each mining section into one or more drill blocks or "pads" which, as a whole, cover the extent of the mineralization in the entire mining section.

[0055] A pad is a drilling site that groups the wellheads for a specific number of exploratory wells at the surface, placing them at very close intervals. Only one drill rig is used in each pad, and all the holes in the pad are drilled by moving them over. Therefore, the smaller the spacing between the holes, the shorter the moving distances and the more efficient the process.

[0056] A pad can typically contain five to ten exploration wells or their wellheads, each of which provides access to several parallel underground recovery drilling sections.

[0057] Once one or more of these underground extraction drilling sections have been completed and backfilled at a wellhead, the fully assembled, drill-ready drilling rig can be transferred to the next wellhead using a semi-mobile transport element. These semi-mobile transport elements include, for example, hydraulic crawler, walking, sliding, or rail systems.

[0058] The pad drilling method allows groups of boreholes to be drilled very efficiently while minimizing the overall ecological footprint of the process at the surface.

[0059] For this purpose, a routing system is preferably provided between the wellheads of a drilling block to allow the drilling rig to be transferred to the next wellhead ready for drilling. To ensure the required production capacity per month or year, production can take place simultaneously in several pads, each with one drilling rig. Pad drilling methods thus allow a large area of ​​valuable underground mineral reserves to be extracted simultaneously while keeping the impact on the surface as minimal as possible.

[0060] It is therefore preferably provided that the drilling rig has semi-mobile transport elements and in a fourth step is transferred to a new borehole head with the aid of its semi-mobile transport elements, at which the extraction drilling unit again drills through a rock layer with an alignment drilling section in a first step and is thereby selectively and precisely guided into an extraction zone, in a second step a 3D drilling grid consisting of several extraction drilling sections is created at the end of the alignment drilling section and in a third step three-dimensional parallel extraction drilling sections are drilled, wherein between the final outer diameters of two adjacent extraction drilling sections there is a distance of a maximum of 45 cm, measured in the common normal direction of the two adjacent borehole axis sections,wherein one extraction drilling section is drilled after the other and after completion of an extraction drilling section, this extraction drilling section together with the associated alignment drilling segment is secured, preferably by complete cementing.

[0061] The distance between the outer diameters of two borehole sections which are precisely parallel to the extraction of the valuable mineral rock is preferably a maximum of approximately 45 cm, particularly preferably a maximum of approximately 40 cm, furthermore preferably a maximum of approximately 30 cm, regardless of whether these sections are straight or, for example, curved in any direction following the direction of the mineralisation, whether they are arranged vertically, inclined or flat, whether they start from the surface or only under an arbitrarily thick overburden underground, or whether they are short or several hundred metres long.

[0062] Especially with long or deep boreholes, conventional directional drilling methods result in significant deviations between the actual and planned borehole positions. With the technologies commonly used, deviations of approximately 70 cm per 1,000 m of borehole length are not uncommon. These deviations result primarily from the measurement accuracy of the inclination and azimuth angles, as well as the propagation of errors in the measurement of the borehole profile.

[0063] For longer boreholes, existing methods require that the individual boreholes be relatively far apart from each other, since, on the one hand, there is a risk of collision with other parallel boreholes and, on the other hand, the planned narrow borehole path cannot be maintained. This, however, significantly reduces the efficiency of the drilling, since the gaps between the boreholes cannot be reduced.

[0064] To keep the deviations between the respective measurement result and the actual position of the borehole measurement point along the entire borehole as small as possible, and thus enable smaller distances between the individual boreholes even with longer borehole lengths, it is preferred that the directional drilling technology of the drilling rig incorporate multiple measuring units with different sensor sets. The measuring units are arranged in the extraction drilling unit, record the surveying, navigation, and geophysical rock information in the borehole, and transmit this to a control element located above ground.

[0065] Preferably, it is provided that for the determination of the position of the

[0066] A series of measurements of the borehole axis of a borehole is carried out during drilling by a first navigation measuring unit and a second navigation measuring unit, so that within a borehole a first series of measured values ​​is obtained by the first navigation measuring unit and a second series of measured values ​​is obtained by the second navigation measuring unit. For this purpose, two surveying navigation measuring units are installed in the extraction drilling unit, with the help of which two independent measurements are carried out for the same borehole section during drilling. The borehole axis of a borehole section is therefore measured twice independently of one another, which makes it possible to increase the positional accuracy of the borehole course through multiple measurements.This significantly reduces the position measurement error and the magnitude of the error propagation of a single navigation measurement unit, allowing a more precise determination of the position of each borehole segment through center position calculation and reducing the probability of an excessive deviation of the actual position from the measured position. As a result, the risk of collision between two boreholes is significantly reduced. This method makes it possible to reduce the distance between two borehole sections, which are precisely aligned parallel, to 45 cm or less, even for long borehole lengths.

[0067] The navigation measurement units each measure the same variables along a series of measured values, e.g., the inclination angle and the azimuth angle. The navigation measurement units can also each include multiple sensors, e.g., one sensor for the inclination angle and one for the azimuth angle, in order to determine the respective position of a measuring point as accurately as possible. The position sensors can also include gyroscope sensors, for example.

[0068] Depending on the accuracy requirements, in addition to the two navigation measuring units in the extraction drilling unit, any number of additional measuring units can be arranged one behind the other in the drill string at any distance from the drill bit. Furthermore, the number of multiple surveys can be increased by raising the entire drill string backward one or more times and then lowering it forward again, particularly after each drill rod or before each drill string extension, or—as is preferably used in the extraction drilling sections—after an extraction drilling section has been extended by a specific borehole segment length.

[0069] For example, the standard deviation of a measurement parameter calculated by averaging six independent individual measurements is reduced by approximately 60% compared to the individual measurement.

[0070] This increase in positional accuracy by approximately 60% is preferably sought in the third step of the method according to the invention for producing an extraction drilling section as follows.

[0071] The starting point for a method according to the invention is preferably a conventional deposit model which is converted into a high-resolution model in a first adaptation step. Based on this adapted model, it is planned which mining sections are to be used to extract valuable mineral rock. The method arrangement according to the invention makes it possible to steer the individual extraction drilling sections selectively and precisely into the planned mining blocks and to extract only the desired valuable mineral rock from underground and to transport it to the surface. Sections with too little or no valuable mineral content are selectively left out or bypassed by the extraction drilling sections and are therefore not mined. If necessary, such areas can only be drilled through or excavated with the smallest possible borehole diameter.in order to minimize the amount of waste rock extracted and, on the other hand, to be able to extract the deposit area still located after the waste zone using borehole extension techniques.

[0072] The process makes it possible to extract even small, i.e. small-quantity raw material deposits which are not profitable using conventional methods. In comparison to a conventional underground mining design, the process according to the invention does not require very capital-intensive initial investments for long-lasting underground mining facilities, such as shaft systems and / or ramp excavations as well as the extraction and preparation facilities that open up the deposit sections over large areas, including the associated conveying, water management and ventilation systems. The process according to the invention can be stopped or interrupted at any time after completion and securing of the last drilled sections produced using the invention and continued at a later time without the remaining parts of the deposit becoming unminable due to rock instability or the capital invested underground having to be written down at a loss.

[0073] For the purposes of the invention, a drilling rig is understood to mean all the elements required to create a borehole. The drilling rig thus includes, for example, the actual drilling rig with the drilling tower above the borehole head at the surface, the standpipe for securing the borehole head at the surface, the drill string consisting of the individual drill rods and drill collars, and finally, the extraction drilling unit between the last drill rod or drill collar and the lowest point in the borehole.

[0074] The drilling rig is equipped with directional drilling technology that enables precise directional deflection and control during every phase of the drilling process. High-precision directional drilling technology is preferred. In particular, it makes it possible to drill holes or borehole sections of any length, both vertically and horizontally, as well as in any inclined or curved direction.

[0075] In its basic configuration, the extraction drilling unit preferably comprises a drill bit at the deepest point in the borehole and, in the immediate vicinity behind it, a drilling steering unit and a first navigation measuring unit. In addition, a geophysical measuring unit, a second navigation measuring unit, a first borehole extension unit and, if appropriate, a second borehole extension unit can also be installed downstream of the first navigation measuring unit, with a first extension unit always being arranged downstream of the surveying and geophysical measuring units and a second extension unit always being installed at the end of the extraction drilling unit. The distance between the first and second extension units preferably corresponds to the typical length of a borehole segment for extending an extraction borehole section.

[0076] The drill bit points in the planned, regular drilling direction and drills the first, inner borehole diameter of an extraction borehole section. During the drilling process, the first navigation measuring unit measures a first series of measured values ​​along the associated borehole profile in the regular drilling direction. Furthermore, it is preferably provided that a second, downstream navigation measuring unit accordingly measures a second series of measured values, and a geophysical measuring unit registers a first series of rock measured values ​​of the just-drilled rock segment.

[0077] During this phase, if applicable, the expansion devices of the first and second borehole expansion units are adjusted (deactivated), and the entire borehole is extended in the first borehole diameter by a specific length of a borehole segment in the regular drilling direction. In the area of ​​the first drill collar, which adjoins the extraction drilling unit at the rear, a borehole diameter that has been enlarged for the first time and is larger than the first, inner borehole diameter, and if applicable, a borehole diameter that has been enlarged for the second time and is larger than the borehole diameter that has been enlarged for the first time, are already formed, preferably as a result of previous drilling phases.

[0078] In order to further improve the accuracy of position detection by the navigation measuring units, it is preferably provided that after recording the first series of measured values ​​and the second series of measured values, the drilling progress is stopped and then the extraction drilling unit is moved backwards in the direction away from the deepest point of the borehole. During the backward movement of the extraction drilling unit, a series of measurements is preferably carried out by the first navigation measuring unit and by the second navigation measuring unit, so that a third series of measured values ​​and a fourth series of measured values ​​are obtained within the borehole. At the same time, a second series of rock measured values ​​of the associated rock segment can be measured using the geophysical measuring unit.

[0079] After recording the first and second series of measured values ​​and after completion of the borehole extension by the planned borehole segment, the drilling progress is briefly stopped, although the borehole flushing is continued. It is preferably provided that the expansion devices of the first expansion stage are then switched off (activated) and the extraction drilling activity is then continued backwards, i.e. opposite to the regular drilling direction away from the deepest of the borehole. The associated borehole segment is enlarged in the backward cut to the borehole diameter of the first expansion stage. It is therefore preferably provided that the borehole is enlarged during the backward movement by a first borehole expansion device arranged in the extraction drilling unit.

[0080] Furthermore, it is preferably provided that after recording the third series of measured values ​​and the fourth series of measured values, the backward movement of the extraction drilling unit is stopped and then moved again in the drilling direction towards the deepest point of the borehole, wherein during the movement to the deepest point of the borehole, a series of measurements is again carried out by the first navigation measuring unit and by the second navigation measuring unit, so that a fifth series of measured values ​​and a sixth series of measured values ​​are obtained within the borehole. This further improves the accuracy of the position measurements in the borehole. At the same time, a third series of rock measured values ​​of the associated rock segment is preferably measured using the geophysical measuring unit.

[0081] In this case, it is preferably also provided that the expansion devices of the second expansion stage are deployed (activated), those of the first expansion stage remain deployed, and the associated borehole section is further expanded during the forward movement by a second borehole expansion stage arranged at the end of the extraction drilling unit. It is therefore preferably provided that the borehole is expanded during the forward movement by a second borehole expansion device arranged in the extraction drilling unit.

[0082] Furthermore, it is preferably provided that the first series of measured values ​​and, if applicable, the second series of measured values, the third series of measured values, the fourth series of measured values, the fifth series of measured values, and the sixth series of measured values ​​are fed to a central control element on the surface, wherein the central control element calculates the mean spatial position of the borehole axis of the respective borehole segment from the obtained series of measured values. This significantly improves the accuracy of determining the position of the borehole axis in the associated borehole segment.

[0083] Furthermore, it is preferably provided that the drilling rig is controlled by the central control element based on the obtained measurement results. This allows, based on the higher accuracy of the position determination of the current borehole path, the drilling rig to be controlled more frequently and earlier to regulate or correct the current drilling direction in order to correct undesirable borehole deflections in a timely manner and to adhere to the planned borehole path as precisely as possible.

[0084] For two boreholes located very close to each other, the geological and geotechnical conditions will most likely be almost identical or at least very similar with regard to the relevant drilling parameters.

[0085] The surveying and geophysical measurement series determined during the creation of a first borehole, e.g. an extraction borehole section, particularly those that characterize the undesired borehole deviations from the planned borehole course, can be used very reliably to plan and control an extraction drilling unit guided in a second borehole that is located very close to the first borehole. In particular, an expected deflection in the second borehole, which is already known, for example, from the measurement results of the first borehole, can be avoided or reduced before it occurs through planning and appropriate countermeasures, so that the planned course of the second borehole can be better adhered to.

[0086] Preferably, the measurement and correction are carried out essentially in real time. In addition to the measurement results of the navigation and geophysical rock parameters, measurements from other sensors on the drilling rig can also be used, which particularly influence and characterize the borehole path.

[0087] These so-called "foreseeable borehole deflections", which are unavoidable given certain geological conditions along the borehole path, can be avoided or minimized by anticipating them, i.e. by taking them into account in advance when calculating the orientation data for the planned borehole path. The expected deflection angle in the spatial plane between the deflection and the desired orientation is mirrored in the desired direction and is taken into account in the calculation of the planned orientation as the required return angle to the desired orientation. In other words, the direction of the planned borehole is oriented in the mirrored deflection direction and requires the expected deflection in order to end up in the desired direction.

[0088] The expected borehole deflections can be estimated fairly well in advance from the following data: a) very generally on the basis of the continuous, operational experience regarding the deflection when drilling through known rock formations with known reservoir geological and geotechnical properties on the one hand, and b) the precisely known, measured, actual borehole deflections on the other hand, which are documented in the digitally integrated system of the invention with the historical, operational borehole data in immediately adjacent boreholes.

[0089] In this preferred method, a series of planned and actual data are linked in a holistic, digitally integrated system. For example, the values ​​and parameters recorded by sensors for borehole drilling are integrated, as are those for navigating the borehole precisely into the planned mining blocks, or the geophysical rock features measured in the borehole. The entirety of all these planning and measurement systems, including their digital datasets, is ultimately linked in a holistic, integrated manner with the digital laboratory data of quality management.

[0090] In the operational processes of extraction, processing and quality control, a digitally integrated sensor system can be provided, among other things, which serves the highly selective sensor-controlled identification of the various valuable mineral and waste rock characteristics underground in the borehole and the likewise highly selective sensor-based sorting of valuable mineral rock and separation of waste rock in the processing above ground.

[0091] The method preferably relies on three sets of sensors. The first set is located essentially at the bottom of the borehole and is preferably installed in the immediate vicinity of the drill bit in the extraction drilling unit. The second set is located above ground, for example, in the processing unit for separating the cuttings from the drilling fluid, and the third set is located in the valuable mineral processing unit for separating valuable mineral rock from waste rock and producing valuable mineral concentrates.

[0092] Apart from the drilling and navigation sensors, each of the three sensor sets mentioned is equipped with the same or similar sensors that are suitable for measuring the same or similar geophysical signals. These can be, for example, density sensors, magnetic field sensors, sound wave sensors, infrared sensors, X-ray or gamma radiation sensors. The geophysical signals of the first sensor set, which are continuously measured deep in the borehole using a series of different sensors, characterize the valuable minerals, valuable mineral contents and / or rocks actually encountered and extracted. These sensor signals are used to identify and measure the essential raw material and rock characteristics of a very small mining unit directly at the mining site in the borehole.

[0093] In addition to these currently measured signals, the calibrated estimated values ​​(planned values) for these signals from the deposit model and the mining planning are also available, preferably for this mining unit that is currently being drilled, and in addition to this, the quality data of all mining blocks that have already been mined and processed in the immediate vicinity (with a distance of less than one meter) of this mining unit, which were precisely determined in the quality laboratory.

[0094] All of this data is preferably used for integrated data reconciliation, data verification and continuous improvement of process management in data reconciliation loops, both for simulation (planning) and for operational control, monitoring and optimization of processes and process results.

[0095] The same or similar sensors and signals are also used in the downstream processes.

[0096] The second sensor set is preferably installed above ground in the processing unit for separating the drill cuttings from the drilling fluid. These sensor signals are used to quickly identify, verify, and separate pure waste rock without valuable mineral content before it is fed into the downstream processing processes.

[0097] The third sensor set is preferably used in sensor-based valuable mineral sorting and waste rock separation for the production of concentrates.

[0098] The processing of the extracted mining unit takes place in the form of cuttings, preferably directly after and in direct connection with the drilling activity of the respective drilling rig. It is preferable not to combine or mix the extracted mining units or blocks, i.e., each extracted mining block is processed separately.

[0099] For this purpose, it is preferably provided that the drilling progress is stopped at a point in an extraction drilling section, with the flushing of the borehole continuing uninterrupted, and after a defined period of time, the drilling process is resumed so that the cuttings produced before the drilling process was stopped can be clearly distinguished from those after the drilling process. This makes it easy to separate the cuttings drilled in the borehole in the individual mining blocks and subsequently process them separately above ground.

[0100] As part of the quality management in processing, the system-relevant mass flows can be representatively sampled for each mining block.

[0101] The quality laboratory analyses of this production and product sampling represent, in their entirety, the actual raw material characteristics of the mined block. This actual characteristic is preferably assigned to the actually measured sensor signals within the framework of one or more data comparison loops, which particularly preferably run continuously and digitally integrated between the individual processes. The comparison loops are preferably structured as follows. Preferably, one or more of these loops are carried out. In a first data comparison loop, the final raw material parameters of a mining block, which are derived from the quality laboratory data, are compared with the data and signals measured by the sensors at the bottom of the borehole.

[0102] In a second comparison loop, the final raw material parameters of a mining block are also compared with the data and signals from the sensors in the valuable mineral and rock sorting.

[0103] In a third comparison loop, the final raw material parameters of a mining block, including the data and signals from the sensors in the deep borehole and in the rock sorting, are then compared with the corresponding estimated values ​​of the deposit model and the mining planning.

[0104] In a fourth adjustment loop, the estimated values ​​for the currently extracted and processed mining block are finally replaced by the corresponding actual data in the deposit model and new, refined estimated values ​​for future mining blocks are determined by means of a recalculation or automatic re-modeling.

[0105] This provides the starting point for the next process run, but with a refined database for mining planning and process control.

[0106] Even if one or two sensor sets are defective and / or deliver unusable signals, the system's functionality remains fully intact and operational, as the precise raw material data from all previously mined blocks located in the immediate vicinity of the current mining unit provide a reliable data replacement. The method can therefore be carried out without problems even in this case. The preferred integrated functionality of the method according to the invention comprises, for continuous digital data comparison, on the one hand, a) rapid real-time data comparison loops within individual process sections and, on the other hand, b) data comparison loops in batch mode.

[0107] The four data comparison loops explained above describe the batch mode and can only be carried out when the laboratory data of at least one mining block of an extraction borehole are reasonably available.

[0108] Real-time data comparison loops are used for process control, monitoring and correction in real time.

[0109] The real-time comparison of planned data with current actual data is generally considered as "validation" of the planned data and, in the case of a minor deviation, as real-time recording of a process deviation from planned target values.

[0110] In the data comparison loops, validated plan data are preferably replaced by their current determined actual data, while identified deviations trigger the calculation of correction factors and subsequently lead to a recalculation of corrected plan data.

[0111] Through process intervention and the application of the corrected plan values, deviations can then be reset and the original plan history restored, or less accurate plan data can simply be replaced with more accurate actual data.

[0112] Before the procedure is carried out, the sensor system is preferably reliably calibrated in all its components. This can be done in two steps: a) the initial calibration of the sensors using existing samples and data and the conventional reservoir model, and b) the final calibration of the entire system for operation, which is carried out in one or more pilot boreholes drilled in the immediate vicinity of existing core holes.

[0113] During the initial calibration, the sensors are tested and calibrated in extensive experiments based on the rock samples available for the conventional reservoir model, including the associated laboratory analyses.

[0114] During final calibration for operation through one or more pilot holes, a pilot hole is positioned and drilled in close proximity to an existing core hole that reflects the actual status of the geology and mineralization at that specific geological location. The distance between the pilot hole and the existing core hole should not exceed 2 m to ensure maximum accuracy and reliability for data correlation.

[0115] Of particular importance for the preferred calibration process (and later also for the preferred real-time adjustment) are the sensor signals measured for each rock or borehole segment in the borehole (with the first sensor set), at the borehole head during the separation of the cuttings from the drilling fluid (with the second sensor set) and finally in the sensor-based valuable mineral sorting (with the third sensor set).

[0116] The sensor signals of the three sensor sets actually measured during pilot operation are assigned to the raw material and deposit characteristics actually identified in the core drilling at this point, thus calibrating the system for operation.

[0117] Furthermore, a system for carrying out a method according to the invention is preferably provided, comprising a drilling device with directional drilling technology, which is designed to produce a borehole extension, as well as devices for securing the boreholes.

[0118] The system comprises a drilling rig with directional drilling technology in the sense of the invention and is designed, among other things, in such a way that borehole extensions can be produced and the securing of the boreholes can be supported.

[0119] Furthermore, the system preferably comprises an extraction drilling unit, a plurality of sensors used by the process and a central control unit.

[0120] The system preferably comprises at least a first navigation measuring unit and a second navigation measuring unit.

[0121] It is preferably provided that the extraction drilling unit comprises a drill bit, a drilling steering unit, a first navigation measuring unit, a geophysical measuring unit, a second navigation measuring unit, a first borehole extension unit and a second borehole extension unit.

[0122] In order to further increase the selectivity of the method according to the invention underground, the extraction drilling unit preferably has further sensors which are designed to detect the type of surrounding rock or of the rock material drilled by the drilling rig. The further sensor(s) are preferably designed to detect and identify valuable mineral enrichments in the borehole. These sensors are essential for the method and make it possible to detect and identify valuable mineral enrichments in the borehole. This allows the actual condition underground to be compared with the deposit model and this to be continuously adapted, preferably in batch mode. With regard to the further sensors used, for example sensors for measuring the hook load on the drilling rig orthe contact pressure of the drill bit and the rotation of the drill head, or acceleration sensors, sensors for measuring density, conductivity, magnetic field, sound waves or infrared, near-infrared, gamma ray or X-ray radiation are provided.

[0123] The navigation measuring units and / or other sensors are preferably connected to the extraction drilling unit in an interchangeable manner, allowing for replacement as needed. In particular, the sensors can be adapted to the rock materials expected in the respective extraction project in order to obtain reliable measurement results.

[0124] The system can collect, correlate and compare all data acquired by sensors as well as from preparatory models - from the deposit model to mining planning and the drilling operation itself, right up to the sorting and processing of the extracted material - in a central control unit. This allows for the control and improvement of both the models and the specific operational processes. This provides a holistically integrated system in which the individual process steps in the extraction and processing of raw materials, particularly solid mineral raw materials, are digitally linked. This enables a system in which data measured in one step of the process can be used in all steps to improve the current extraction process and the respective models or simulations using real data.The system preferably further comprises a sorting or processing plant downstream of the drilling operation, in which the extracted material, in particular the extracted rock, is crushed, classified, sorted, and processed into a concentrate. The processing plant is preferably located above ground. The holistically integrated linking of data across the entire mining value chain achieves greater selectivity in both extraction and processing, thus resulting in a significant reduction in the amount of waste rock extracted.

[0125] The process according to the invention is not limited to a specific form or type of mineralization or deposit. The process according to the invention can

[0126] • be applied to any deposit in any shape, size and depth, regardless of whether it is exposed or exposed at the surface, or is overlain by thick overburden without exposure at the surface, regardless of whether it is located underwater (i.e. under rivers, lakes or offshore) or under another reservation zone identified as sensitive at the surface, and also

[0127] • below or outside the final mining model boundaries of existing opencast mines (in particular below the deepest mining level or deposit sections under high end slopes overlain by thick rock layers), with the aim of extending and maximising the use of existing asset values, and

[0128] • Mining at any depth , even below the deepest level of today 's conventional underground mining .

[0129] Its applicability is tied to a type of mineralization that allows for selective mining and selective sorting of valuable minerals. Furthermore, it is limited by the rock strength and the market value of the total marketable metal and mineral content contained in the total mining output.

[0130] The method and the system can be used in any type of drilling, preferably in the extraction of solid mineral raw materials. In particular, the method and the system are independent

[0131] • the type, size or total weight of the drilling rig,

[0132] • the drilling method used, e.g. rotary, percussive or rotary-percussive,

[0133] • the flushing method used, e.g. dry with compressed air, or wet with compressed air, or compressed air with foam, or in the reverse circulation process, or wet with a standard drilling fluid used in oil and gas drilling technology,

[0134] • the selected drive system, e.g. whether the drive for percussive, rotary percussive or rotary drilling is from above ground or in the borehole,

[0135] • of any type, design and diameter of drill bit or generally any other drilling or cutting tool on the bottom of the borehole,

[0136] • the final borehole diameter of a borehole preparing for extraction or of a borehole segment serving this purpose or of an extraction borehole directly serving the extraction or even just a extraction borehole segment serving this purpose, which is drilled with a constant diameter in only one continuous complete pass or in only one pass which is divided into partial sections or.is interrupted, is produced, or in - as before for a continuous whole or divided into sections, interrupted - a single pass with additional single or multi-stage borehole enlargement, or - as before for a single continuous whole or divided into sections, interrupted pass - in two or more passes, each with single or multi-stage borehole enlargement (under-reaming), whereby in the two or more passes for each pass an additional exchange of the entire Bore-Hole-Assembly (BHA) unit can also be carried out, if necessary also optionally with the additional exchange of the single or multi-stage borehole enlargement technology.

[0137] • of any type, technology, dimension and quality of borehole casing used,

[0138] • of any type, technology and specification of the borehole filling or cementing used,

[0139] • any type of combination of borehole casing and borehole backfilling,

[0140] • the grain size and / or grain size distribution of the drilling mud or cuttings,

[0141] • any number and type of integration or installation of navigation / orientation measuring units into the drill string,

[0142] • any type of technology used for navigation monitoring, borehole deflection and direction correction of the borehole string or the borehole bit,

[0143] • of any type, technology, arrangement, equipment, precision and integration of sensor units into the drill string for the purpose of navigation and logging while drilling and / or measurement while drilling,

[0144] • of any distance between two and / or more boreholes used for the preparation and / or direct extraction of solid mineral resources at the surface,

[0145] • whether boreholes intended for the extraction of solid mineral raw materials start directly at the surface or only below a layer of any thickness

[0146] De ckgebirgsschicht ,

[0147] • on how the ore recovery rate develops over a test period and / or the regular operating time, and regardless of whether this only reaches a few percent or even almost 100% at any time along this timeline, • on whether an individual well and / or an initial well in any combination with other wells, each of which serves or could serve the fact and / or possibility of preparing and / or directly extracting solid mineral raw materials, is designated or established and sunk or produced as a pilot, test, exploration or infill well, and only later - at any time - is or could be expanded in one or more subsequent runs using the available technologies for successive well expansion,

[0148] • whether a directional drilling method used has the functionality and ability to actually produce the parallel boreholes exactly parallel, or whether this only occurs approximately parallel, or whether these oscillate uncontrollably in all directions and with any deviations around the target or planned course and in the process approach, touch, cross or drift apart from one another, and regardless of how small or large the borehole spacing or borehole lengths are, and regardless of whether this occurs in one, several or very many boreholes, and regardless of whether this happens rarely, very frequently or regularly in a borehole.

[0149] The invention makes a groundbreaking contribution to the "responsible and sustainable procurement of critical metals and minerals," as unequivocally demanded worldwide by ESG (Environmental, Social and Governance) requirements for sustainable investments and modern, responsible industrial management in the areas of green technology, renewable energy, e-mobility, digitalization, and decarbonization.

[0150] The invention thus offers a highly sought-after alternative to the conventional extraction and processing of critical metals and minerals in modern industry. It is a disruptive innovation that makes a significant contribution to more sustainable and digital processes in mining.

[0151] The invention is explained in more detail below using an exemplary embodiment shown schematically in the drawing. In this, Fig. 1 shows a first step of a method according to the invention, Fig. 2 shows a second step of a method according to the invention, Fig. 3 shows a third step of a method according to the invention, Fig. 4 is a cross-sectional view of a 3D drilling grid, Figs. 5 to 9 show various options for a 3D drilling grid, Fig. 10 is a cross-section of a 3D drilling grid with sequence order, Fig. 11 is a cross-section of a drilling grid with borehole extensions, Fig. 12 is a vertical section of an excavation plan, Fig. 13 is an overview of a preferred method in longitudinal section, Fig. 14 shows a further preferred method for the semi-mobile transfer of the drilling rig and Figs. 15 to 18 show a preferred method according to the invention in the borehole.

[0152] Fig. 1 shows a preferably provided step prior to the first step of a method according to the invention, in which an exploratory drilling section 2 starts at the borehole head 3 on the surface 1 and is drilled vertically through a rock layer 5 via a standpipe 4. An exploratory drilling section 2 is followed by an alignment drilling section 6 (Fig. 2).

[0153] In Fig. 2, a first step of a method according to the invention is shown, wherein following an alignment drilling section 6, a 3D drilling grid 7 is prepared from several extraction drilling sections 8. The alignment drilling section 6 has a curved first

[0154] Segment 6a and several curved second segments 6b, with which the 3D drilling grid 7 is created. Fig. 3 shows a third step of a method according to the invention, in which the extraction drilling sections 8 prepared in the second step are carried out. In the embodiment shown, several segments 6a, 6b, 6c of the alignment drilling section 6 are provided, each of which ends in a 3D drilling grid 7 of several extraction drilling sections 8.

[0155] Fig. 4 shows an exemplary drilling grid 7 in a cross-sectional view. The individual extraction drilling sections 8 can, as shown, have different diameters. Furthermore, the extraction drilling sections 8 are only arranged in areas with sufficient mineralization, while waste rock areas 9 are either left out or can only be drilled or penetrated with a small borehole cross-section.

[0156] Fig. 5 shows a first 3D drilling grid 7 in which all extraction drilling sections 8 have the same diameter and the same distance from one another. The extraction drilling sections 8 are each arranged in bundles 10 of seven extraction drilling sections 8, in which six extraction drilling sections 8b are evenly arranged around a central extraction drilling section 8a.

[0157] Fig. 6 shows a second 3D drilling grid 7, wherein, in contrast to the 3D drilling grid 7 according to Fig. 5, the distances between the extraction drilling sections 8 are not always the same, but rather a waste rock area 9 is left out. For this purpose, the bundles 10 are each designed as in the embodiment according to Fig. 5, although there is sometimes a larger distance between the individual bundles 10.

[0158] In Fig . 7 a third 3D drilling grid 7 is shown, in which, in contrast to the design according to Fig . 6, the individual bundles 10 are not fully formed, but individual extraction drilling sections 8b are missing, as shown by the circles 11.

[0159] Fig. 8 shows a fourth 3D drilling grid 7. In contrast to the embodiment according to Fig. 5, the central extraction drilling sections 8a of the bundles 10 are each formed with a larger diameter than the remaining extraction drilling sections 8b.

[0160] In Fig. 9, a fifth 3D drilling grid 7 is shown, wherein a bundle 10 with seven equally sized extraction drilling sections 8, a bundle 10 with a larger central extraction drilling section 8a and a bundle 10 with a larger central extraction drilling section 8a and five extraction drilling sections 8 surrounding the central extraction drilling section 8a are formed, wherein the extraction drilling sections 8c partially overlap with the central extraction drilling section 8a and the extraction drilling sections 8d have a smaller diameter than the extraction drilling sections 8c.

[0161] Fig. 10 shows a further 3D drilling grid 7, where the individual extraction drilling sections 8 are labeled A, B, C, D, E, which indicate one of many possible drilling sequences. The sequence begins with sequence “A” and all extraction drilling sections 8b labeled “A” on the left in the top row and continues to the right, followed by the next row directly below and so on as required until the last row is drilled. This sequence ensures, on the one hand, that there is sufficient distance between the holes drilled one after the other in sequence “A”, and, on the other hand, that the backfilling / cementing of the completed holes has sufficient time to harden before the more closely adjacent borehole in sequence “B” is drilled. After sequence “A” has been completed, sequence “B” begins in the same way with all extraction drilling sections 8b labeled “B” at the top left.After completion of sequence "B", the entire ring structure of all bundles 10 is complete. In the following sequences "C", "D" and "E", the remaining space within the bundles 10 is drilled out using extraction drilling sections 8a. This can be done, as required, with the same diameter as sequences "A" and "B", or with a larger diameter that reaches up to the extraction drilling sections 8b or slightly overlaps them. The smaller the distances, the higher the so-called deposit recovery, which can be up to 90% with a slight overlap. The sequence of drilling and the immediate securing of each extraction drilling section 8 by complete cementing ensures that a sufficient degree of rock stability is maintained at all times.

[0162] Fig. 11 shows a further 3D drilling grid 7, wherein the individual extraction drilling sections 8 are labeled A, B, and C, which indicate the drilling sequence. Furthermore, a borehole enlargement of the extraction drilling sections 8 is shown. The outer extraction drilling sections 8b, labeled A and B, are enlarged to the final outer diameter using an enlargement stage of the extraction drilling unit. The central extraction drilling section 8a is produced with two passes and two enlargement stages.

[0163] Like the sequencing of the boreholes, the way in which the final borehole diameter is produced from parallel, closely spaced boreholes is of great importance for ensuring sufficient rock stability at all times during the drilling process. The final outer borehole diameters of a borehole according to the invention or of a borehole segment according to the invention are preferably produced using the borehole enlargement method according to Fig. 11. Fig. 12 shows a vertical section of a mining plan for a method according to the invention, schematically shown in dip, in which the extraction drilling sections 8 are each guided parallel in the 3D drilling grids 7 and their vertical arrangement is shown in the block model of a conventional deposit model.

[0164] Fig. 13 shows a schematic longitudinal section of an extraction method according to the invention, in which the drilling process is carried out using several drilling rigs at several locations simultaneously. The deposit is divided into four extraction sections 12, each approximately 200 m long in the down-dip direction of the deposit. The direction of the extraction drilling sections 8 follows the generalized down-dip direction of the deposit or mineralization. Between the extraction sections 12, a safety pillar 13 of approximately 30 m remains in the down-dip direction, which is not systematically mined. In the strike direction, i.e. in the horizontal direction normal to the dip, the deposit is divided into extraction sections, each approximately 125 m wide, with each of these extraction sections being accessed from the surface by means of four drill blocks 14 (so-called "pads"). There is no safety pillar between the extraction sections in the strike direction.The four down-dip mining sections 12 are being worked or mined simultaneously and, for reasons of rock stability, are alternately offset along strike by the pad route length of 125 m. In a subsequent mining phase, the drill blocks 14 shown are mined along the connecting road 15 in opposing mining sections. Thus, a total of eight mining sections are mined in two successive phases, each with four sections, within a total mining area of, for example, 22.5 hectares. A connecting road 15 is arranged down-dip between the four drill blocks 14 shown along strike. From this road, the 125 m long pad routes 16 are accessed in the strike direction. In each pad route 16, four drill blocks 14 are arranged in the direction of the pad route 16.

[0165] In Fig. 14, an exemplary arrangement of the borehole starting points or borehole heads 17 within a drilling block (a so-called pad) 14 is shown in detail. Each drilling block (pad) 14 comprises five planned borehole heads 17, which are arranged in close proximity to one another and between which a drilling rig can be transferred in an operational state by means of semi-mobile transport units. The illustrated borehole heads 17 are arranged in the direction of the pad route 16, wherein a borehole head

[0166] 17 is arranged in the central position and two boreheads 17 are arranged symmetrically to the central position on each side. The required production capacity is provided by the simultaneous operation of one drilling rig on each of several drilling blocks 14 and their rapid, operational transfer between the boreheads 17 of a drilling block 14.

[0167] Fig. 15 illustrates a first phase of an application of an extraction drilling unit 19 according to the invention. In the deposit 18, an extraction drilling unit 19 designed to carry out a method according to the invention is shown schematically, which is arranged at the end of the drill string between a last drill rod 20 and the borehole depth 21. The extraction drilling unit 19 comprises a drill bit 22, a drill steering unit 23, a first navigation measuring unit 24, a geophysical measuring unit 25, a second navigation measuring unit 26, a first borehole extension unit 27 and, at the end of the extraction drilling unit 19, a second borehole extension unit 28. The arrow 29 points in the regular drilling direction. The drill bit 22 drills the first borehole diameter 30. During the drilling process, the first navigation measuring unit 24 measures a first series of measured values ​​along the borehole in the direction of the arrow 29.The second navigation measuring unit 26 accordingly measures a second series of measured values, and the geophysical measuring unit 25 measures a first series of rock measured values. During this phase, the first extension stage 27 and the second extension stage 28 are set, and the entire borehole is extended in the first borehole diameter 30 by the borehole segment the length of the arrow 29 in the regular drilling direction. In the area of ​​the drill rod 20, a second borehole diameter 31, which is larger than the first borehole diameter 30, and a third borehole diameter 32, which is larger than the second borehole diameter 31, are already formed.

[0168] Fig. 16 shows a schematic representation of a second phase of a method according to the invention. After completion of the borehole extension by the borehole segment of arrow length 29, the drilling progress is briefly stopped, but the borehole flushing is continued. The expander devices of the first expansion stage 27 are switched off, the drilling activity is continued backwards in the opposite drilling direction, i.e. in the direction of arrow 33, and in the process the borehole is expanded in reverse cut by the borehole segment of arrow length 33 to the first expanded borehole diameter 31. At the same time, a third series of measured values ​​is measured with the first navigation measuring unit 24, a fourth series of measured values ​​with the second navigation measuring unit 26, and a second series of rock measured values ​​is measured with the geophysical measuring unit 25.

[0169] Fig. 17 shows a schematic representation of a third phase of a method according to the invention. After completion of the first borehole enlargement 31, the drilling progress is again briefly stopped, but the expansion devices of the first expansion stage 27 remain switched off and the borehole flushing is continued. Now the expansion devices of the second expansion stage 28 are switched off, the drilling activity is continued again in the regular drilling direction forwards, i.e. in the direction of arrow 29, and in the process the borehole is enlarged in the forward cut to the final second enlarged borehole diameter 32. At the same time, a fifth series of measured values ​​is measured with the first navigation measuring unit 24, a sixth series of measured values ​​with the second navigation measuring unit 26 and a third series of rock measured values ​​with the geophysical measuring unit 25.

[0170] Fig. 18 shows a schematic representation of a fourth phase of a method according to the invention. After completion of the final second borehole enlargement 32, the drilling progress is again briefly stopped, but the borehole flushing remains in operation, the two expanding devices of the first enlargement stage 27 and the second enlargement stage 28 are adjusted and then the entire borehole in the first borehole diameter 30 is extended by the next borehole segment in the regular drilling direction.

Claims

Patent claims:

1. A method for the systematic selective extraction of solid mineral raw materials using a drilling rig with directional drilling technology, in which an extraction drilling unit (19) in a first step, a rock layer (5) is drilled through with an alignment drilling section (6) and is thereby selectively and precisely guided into an extraction zone, in a second step, a 3D drilling grid (7) comprising a plurality of extraction drilling sections (8) is created at the end of the alignment drilling section (6), and in a third step, extraction drilling sections (8) guided three-dimensionally parallel to one another are drilled, wherein a maximum distance of 45 cm is arranged between the final outer diameters of two adjacent extraction drilling sections (8), measured in the common normal direction of the two adjacent borehole axis sections, and wherein one extraction drilling section (8) is drilled after the other and, after the completion of an extraction drilling section (8), this extraction drilling section (8) is secured together with the associated alignment drilling segment (6c).

2. Method according to claim 1, characterized in that the extraction drilling section (8) together with the associated alignment drilling segment (6c) is secured by complete backfilling by cementing.

3. Method according to claim 1 or 2, characterized in that before the first step, a cover layer (5) is drilled through with an exploratory drilling section (2), to which the alignment drilling section (6), preferably with the segments (6a, 6b, 6c), adjoins.

4. Method according to claim 1, 2 or 3, characterized in that the distance between the final outer diameters of two adjacent extraction drilling sections (8) is a maximum of 40 cm, preferably a maximum of 30 cm.

5. Method according to one of claims 1 to 4, characterized in that after completion of the alignment drilling section (6), the alignment drilling section (6) is secured.

6. Method according to one of claims 1 to 5, characterized in that after completion of the exploratory drilling section (2), the exploratory drilling section (2) is secured.

7. Method according to one of claims 1 to 6, characterized in that the final outer diameter of at least one extraction drilling section (8) is produced by means of a borehole enlargement method.

8. Method according to one of claims 1 to 7, characterized in that the drilling rig has semi-mobile transport elements and, in a fourth step, is transferred to a new borehole head using the semi-mobile transport elements, at which the extraction drilling unit (19) again, in a first step, drills through a rock layer (5) with an alignment drilling section (6) and is thereby selectively and precisely guided into an extraction zone, in a second step, a 3D drilling grid (7) consisting of several extraction drilling sections (8) is created at the end of the alignment drilling section (6), and in a third step, extraction drilling sections (8) guided three-dimensionally parallel to one another are drilled, wherein a maximum distance of 45 cm is arranged between the final outer diameters of two adjacent extraction drilling sections (8), measured in the common normal direction of the two adjacent borehole axis sections,and wherein one extraction drilling section (8) is drilled after the other and after completion of an extraction drilling section (8), this extraction drilling section (8) is secured together with the associated alignment drilling segment (6c).

9. Method according to one of claims 1 to 8, characterized in that the directional drilling technology of the drilling rig has a plurality of measuring units (24, 25, 26) with different sensor sets, which are arranged in the extraction drilling unit (19) and record surveying navigation and geophysical rock information in a borehole and send it to a control element arranged above ground.

10. The method according to claim 9, characterized in that during drilling a series of measurements is carried out by a first navigation measuring unit (24) and a second navigation measuring unit (26) so that a first series of measured values ​​and a second series of measured values ​​are obtained within the borehole.

11. The method according to claim 10, characterized in that after recording the first series of measured values ​​and the second series of measured values, the drilling progress is stopped and then the extraction drilling unit (19) is moved backwards in the direction away from the borehole depth (21), wherein during the backward movement of the extraction drilling unit (19) a series of measurements is carried out by the first navigation measuring unit (24) and by the second navigation measuring unit (26), so that a third series of measured values ​​and a fourth series of measured values ​​are obtained within the borehole.

12. Method according to claim 11, characterized in that the borehole is enlarged during the backward movement by a first borehole enlargement device (27) arranged in the extraction drilling unit (19).

13. Method according to claim 11 or 12, characterized in that after recording the third series of measured values ​​and the fourth series of measured values, the backward movement of the extraction drilling unit (19) is stopped and then moved again in the drilling direction towards the borehole depth (21), wherein during the movement towards the borehole depth (21) a series of measurements is carried out by the first navigation measuring unit (24) and by the second navigation measuring unit (26), so that a fifth series of measured values ​​and a sixth series of measured values ​​are obtained within the borehole.

14. Method according to claim 13, characterized in that the borehole is widened during the forward movement by a second borehole widening device (28) arranged in the extraction drilling unit (19).

15. Method according to one of claims 9 to 14, characterized in that the first series of measured values ​​and, if applicable, the second series of measured values, the third series of measured values, the fourth series of measured values, the fifth series of measured values ​​and the sixth series of measured values ​​are fed to a central control element, the mean spatial position of the borehole axis of the respective borehole segment being determined in the central control element from the series of measured values ​​obtained.

16. Method according to one of claims 1 to 15, characterized in that the drilling progress is stopped at a point of an extraction drilling section, wherein the flushing of the borehole is continued uninterrupted, and after a defined period of time the drilling process is continued again, so that the drilling cuttings produced before the drilling process was stopped can be clearly distinguished from those produced after the drilling process was stopped.

17. System for carrying out a method according to one of claims 1 to 16, comprising a drilling device with directional drilling technology, which is designed to produce a borehole extension, and devices for securing the boreholes.

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