Drilling emulsion system

Abstract

The invention relates to a drilling emulsion system comprising a base emulsion unit (10), a mixing and metering unit (20), a control unit (30), and an emulsion main line (50), wherein the base emulsion unit (10) is configured to provide a base emulsion and supply it to the mixing and metering unit (20) via the emulsion main line (50), wherein the mixing and metering unit (20) is connected to the emulsion main line (50) and comprises an additive unit (40) and an emulsion bypass line (51), and is configured to provide a finished emulsion by adding an additive emulsion to the base emulsion, wherein the additive unit (40) comprises an additive storage container (41), a pre-stage actuating element (42), an additive emulsion container (43), and a final actuating element (44), and wherein the emulsion bypass line (51) is connected to the emulsion main line (50) is connected and trained,a bypass actuator (52) is used to meter a sidestream of the base emulsion into the aggregate emulsion container (43), wherein the aggregate emulsion container (43) is designed to provide an aggregate emulsion from the aggregate, wherein the final actuator (44) is connected to and controlled by the control unit (30) and is designed to meter the aggregate emulsion into a main stream of the base emulsion.

Description

[0001] The invention relates to a drilling emulsion system for the variable admixture of subsoil-specific aggregates, in particular for drilling rigs for directional drilling.

[0002] The use of drilling emulsions for drilling underground is known in the art. Such drilling techniques are known in the art as flush drilling, and can also be horizontal drilling.

[0003] The use of drilling emulsions supports the drilling process in several ways. The drilling emulsion softens the soil in front of the drill bit, improving the cutting effect and reducing drilling resistance at the drill bit. At the same time, it cools the drill bit. Furthermore, the drilling emulsion flushes the soil loosened by the drilling process out of the drill bit zone and then further out of the drill channel. Furthermore, the drilling emulsion acts as a tribologically beneficial lubricant, thus reducing friction and wear, even on the drill rod surfaces. The drilling emulsion is also partially absorbed by the soil at the borehole wall and subsequently stabilizes the drill channel.

[0004] The drilling emulsion used in state-of-the-art directional drilling has a dispersion of bentonite in water as its base component, to which aggregates are usually added. The aggregates are used primarily to adapt the drilling emulsion to the specific soil type.

[0005] State-of-the-art technology involves selecting and metering aggregates based on previously determined information about the subsoil. Furthermore, this can be done based on subjective assessment during the drilling process. The disadvantage of this approach is that it requires extensive experience from the rig operator and is prone to errors due to potential misjudgments.

[0006] A dosing device that is, in principle, suitable for providing a drilling emulsion is known from DE 10 2009 023 546 A1. This device enables the introduction of a powdered medium into a liquid, and in particular the introduction of bentonite into water. For this purpose, the device comprises a guide unit and a dosing unit arranged above it with dosing and brush rollers, whereby the powdered medium dispensed by the dosing unit is scattered onto the liquid surface.

[0007] DE 195 45 917 A1 describes a process and an associated device for bentonite dispersion. The dispersion device enables the production, storage, and dosing of bentonite suspensions. Water and bentonite are thoroughly stirred in a mixing vessel, then transported to a dispersion device, where they are subjected to a shearing effect.

[0008] Furthermore, DE 37 33 409 A1 discloses a device for mixing mixture components and their use in the production of bentonite and diaphragm wall suspensions. This device involves the use of a continuous mixing tube with a rotatably mounted mixing shaft, with perforated mixing paddles arranged on the mixing shaft.

[0009] The solutions listed above from the state of the art for providing drilling emulsion are therefore based on manually controlled mixing and dosing processes, resulting in considerable operating effort. Furthermore, the quality of the drilling emulsion provided is primarily determined by the professional experience and knowledge of the operating personnel.

[0010] A solution that advantageously overcomes the disadvantages of purely manual control is described in the document DE 10 2017 002 336 A1. According to this solution, data records containing mineral-specific aggregate formulations are stored in a control unit database. Control commands are generated from these and transmitted to a mixing and dosing device, which contains storage containers for the powdered aggregates and then automatically performs the dosing and mixing into a base emulsion according to the selected aggregate formulation. Furthermore, the selection of aggregate formulations can advantageously be changed during the drilling process. The problem here is that the volumes of drilling emulsion in the mixing process must be consumed before the drilling emulsion is available at the drill head according to the modified selected formulation.

[0011] The object of the invention is to provide a drilling emulsion system, overcoming the disadvantages of the prior art, which allows adaptation to changing ground conditions with a short reaction time and with precise dosing.

[0012] The problem is solved by the features listed in patent claim 1. Preferred developments arise from the subclaims.

[0013] The drilling emulsion system according to the invention is designed to provide a finished drilling emulsion for a drilling rig for a flush drilling operation. The drilling emulsion system is preferably designed as a separate unit, for example, in a container or other base frame, and is connected to a drilling rig. Such a drilling rig can, in particular, be a horizontal drilling rig.

[0014] According to the invention, the drilling emulsion system comprises as basic components a base emulsion unit, a mixing and dosing unit and a control unit.

[0015] The base emulsion unit is designed to provide a base emulsion and feed it to the mixing and dosing unit via an emulsion line. The base emulsion unit preferably has a container into which the initially powdered bentonite and water are introduced. The starting components are mixed there, for example, by stirring. The drilling emulsion system can also be distributed across multiple systems. A tanker truck that holds a prepared base emulsion and is connected via a hose is also considered a base emulsion unit in this sense.

[0016] A base emulsion, as used in the present invention, is a suspension made from bentonite and water—without any additives yet. A finished emulsion is the drilling emulsion created from the base emulsion by adding additives. The finished emulsion is the drilling emulsion dispensed from the drilling emulsion system to the drilling rig. The term "emulsion" used here is taken from the technical terminology of drilling technology and is therefore not identical to the generally accepted chemical category.

[0017] The central physical component is the mixing and dosing unit. It is designed to produce the finished emulsion by adding an aggregate emulsion to the base emulsion.

[0018] The mixing and dosing unit comprises at least one aggregate unit. Preferably, however, there are several aggregate units. The aggregate unit according to the invention comprises an aggregate storage container, a preliminary control element, an aggregate emulsion container, and a final control element. The aggregate unit is designed to produce an aggregate emulsion from a powdered aggregate and to make it available for dispensing.

[0019] The aggregate storage container is designed to hold an aggregate. It is preferably a funnel-shaped container from which the stored aggregate can be metered out using gravity.

[0020] The pre-stage control element is designed to meter the aggregate into the aggregate emulsion container. The pre-stage control element can be designed, for example, as a solenoid valve located at a funnel-shaped outlet of the aggregate storage container. However, it can also be a preferably controllable screw conveyor that can convey powdered aggregate from the aggregate storage container.

[0021] The pre-stage control element can have various operating states. The different operating states allow the amount of aggregate to be removed from the aggregate storage container to be adjusted. In a closed operating state, no aggregate is fed into the aggregate emulsion container, while in an open operating state, a specific amount of aggregate is added to the aggregate emulsion container. The amount of aggregate introduced can be controlled and thus metered by the degree or duration of the opening of the pre-stage control element.

[0022] The aggregate emulsion tank is designed to provide an aggregate emulsion from the aggregate. For this purpose, the aggregate emulsion tank receives the aggregate introduced from the aggregate storage tank by the upstream control element. Furthermore, a portion of the base emulsion is introduced into the aggregate emulsion tank via an emulsion branch line, which is connected to the main emulsion line and discharges a secondary flow of the base emulsion from the main emulsion line. To enable precise dosing, a bypass control element is assigned to the emulsion branch line. Like the upstream control element, the bypass control element can also have various operating states for quantity adjustment, such as a closed operating state or an open operating state. The descriptions for the upstream control element also apply accordingly to the bypass control element.

[0023] The aggregate is mixed with the introduced amount of base emulsion to form a preliminary emulsion. This is referred to as the aggregate emulsion. The aggregate unit can preferably have an agitator or a similar device associated with the aggregate emulsion container to assist in the fine distribution or dissolution of the aggregate, hereinafter also referred to as dispersion. Furthermore, a temperature control device can be provided to assist dispersion. The concentration of the aggregate in the aggregate emulsion can be determined by the amount of aggregate and the amount of base emulsion.

[0024] The final control element, the last functional element of the aggregate unit, is connected to the control unit and receives control commands from it. The final control element is designed to meter the aggregate emulsion into the main flow of the base emulsion remaining in the main emulsion line after the secondary flow has been discharged.

[0025] Like the pre-stage control element and the bypass control element, the final control element can also have different operating states, such as a closed operating state or an opening state that can be determined in time or quantity, so that the amount of aggregate emulsion that is added to the base emulsion and the time of addition can be precisely determined.

[0026] Here, the control unit is designed to provide a final control signal that is designed to control the operating state of the final actuating element. Within the meaning of the present invention, a final control signal is understood to be a control signal for controlling the operating state of the final actuating element, a pre-stage control signal is understood to be a control signal for controlling the operating state of the pre-stage actuating element, and a bypass control signal is understood to be a control signal for controlling the operating state of the bypass control element.

[0027] The control unit is preferably designed as a controller with an electronic circuit and is connected to the sensor elements and actuators. Sensor elements are understood to mean, in particular, the sensor unit, and actuators are understood to mean, in particular, the control elements and the temperature control element.

[0028] The particular advantages of the drilling emulsion plant according to the invention are determined in particular by the aggregate unit.

[0029] The time required for the fine dispersion of the aggregate particles in the base emulsion, as well as their partial chemical dissolution, is advantageously decoupled from the addition to the base emulsion. Furthermore, the quantitative ratio of base emulsion to aggregate is also decoupled from the quantitative ratio in the main stream of the base emulsion. Both of these effects support the provision of a high-quality aggregate emulsion as an intermediate stage before its addition to the base emulsion. This advantageously ensures complete dispersion and thus the full effectiveness of the aggregate, and in particular, avoids or reduces clumping or unwanted compounds with components of the bentonite solid phase of the base emulsion.

[0030] Due to the easily adjustable concentration of the aggregate in the aggregate emulsion, the effective amount of aggregate in the finished emulsion can be precisely determined.

[0031] Furthermore, the total ratio of water on the one hand and bentonite and aggregates on the other hand can advantageously be controlled simultaneously via the aggregate unit and the concentration.

[0032] Another advantage is the high reaction speed. The final control element can be positioned as the inlet point for the aggregate emulsion directly upstream of the discharge point of the finished emulsion from the drilling emulsion system for transfer to the drilling rig, as no longer mixing distance is required after this inlet point. An aggregate formulation defined at the control unit ensures that a corresponding finished emulsion is applied to the drill head in a short time. This also advantageously allows for both discontinuous and, depending on operating conditions, continuous processing of the aggregate emulsion.

[0033] A particularly advantageous solution was also found that is independent of the supply of fresh water, which under real conditions at a drilling site often cannot be guaranteed without disproportionate effort.

[0034] According to an advantageous development, the drilling emulsion system is characterized in that a sensor unit is assigned to the aggregate emulsion container, which is designed to detect at least one state value of the aggregate emulsion from the group: fill level, density, viscosity, conductivity and temperature, and in that the sensor unit and the pre-stage actuating element are connected to the control unit, and in that the control unit is designed to receive the state value from the sensor unit, to process it, and to provide a pre-stage control signal, which is designed to control an operating state of the pre-stage actuating element.

[0035] According to this development, the sensor unit, which preferably has multiple sensors, records condition values ​​of the aggregate emulsion as parameters for its quality and evaluates them via the control unit. Optionally, the sensor unit can also record, for example, a fill level of the aggregate storage container. The parameters can preferably be displayed to an operator and also processed by the control unit. Following the processing of the recorded parameters, parameters can be controlled to influence the properties of the aggregate emulsion. This includes, in particular, the operating state of the upstream control element being adjustable via upstream control commands. The amount of water added to the aggregate emulsion container can preferably also be controlled via control commands from the control unit.

[0036] According to a further advantageous development, the drilling emulsion system is characterized in that the aggregate unit has a temperature control device. The temperature control device is preferably an electric heating source that heats the aggregate emulsion container. This can advantageously enable or accelerate dispersion for special aggregates. Particularly advantageously, the temperature control can be energetically limited to the comparatively small amount of the aggregate emulsion. Temperature control of the high mass flow of the base emulsion, on the other hand, would be neither energetically nor technically feasible. The electric heating source can preferably be controlled automatically via the control unit according to the parameters recorded and processed by the sensor unit.

[0037] According to a next advantageous development, the drilling emulsion system is characterized in that the mixing and dosing system has a plurality of aggregate units.

[0038] The additional aggregate units are preferably constructed in the same way as the first aggregate unit, although modifications to adapt to the specific properties of the respective aggregate are also possible. According to this refinement, several different aggregates can be prepared separately for admixture into the main flow of the base emulsion in the emulsion line. The additional aggregate units also preferably have sensor units connected to the control unit, and the control unit is designed to control the multiple aggregate units in a coordinated and preferably automated manner according to stored aggregate recipes, depending on the subsoil in front of the drill head.

[0039] According to a further advantageous development, the drilling emulsion system is characterized in that the mixing and dosing system additionally includes a liquid aggregate unit. If the aggregates are not powdered but liquid, they can also be injected into the main base emulsion stream in a controlled manner.

[0040] The invention is illustrated by way of example with reference to Fig. 1Schematic overview Fig. 2Schematic detailed representation explained in more detail.

[0041] Identical reference symbols in the various figures refer to identical features or components. These reference symbols are used in the description even if they are not shown in the respective figure.

[0042] Fig. 1 shows the basic structure of an exemplary embodiment of the drilling emulsion system.

[0043] The base emulsion unit 10 comprises a container in which a base emulsion is prepared from water—introduced via a water supply (no reference symbol)—and bentonite. The base emulsion is then fed to the mixing and dosing unit 20 via the main emulsion line 50. In the exemplary embodiment, the mixing and dosing unit 20 comprises, in addition to the aggregate unit 40, another aggregate unit 40-n and a liquid aggregate unit 60.

[0044] Fig. 2 shows the aggregate unit 40 in an enlarged view and with further details.

[0045] The aggregate storage container 41 contains a powdered aggregate. The aggregate can be metered into the aggregate emulsion container 43 via the pre-stage control element 42. In the present exemplary embodiment, the pre-stage control element 42 is an electromagnetically actuated valve connected to the control unit 30 via a connecting line (not shown in a dotted line) and controlled from there by means of control commands, referred to here as the pre-stage control signal. Furthermore, base emulsion is also supplied to the aggregate emulsion container 43 in a metered manner via the emulsion secondary line 51 and the bypass control element 52. For this purpose, the bypass control element 52 is designed as a metering pump with a screw drive in the exemplary embodiment.To support the dispersion, a tempering element 46, here as an electric heating element, is assigned to the aggregate emulsion container 43, which is also controlled via the control unit 30.

[0046] A sensor unit 45 has several individual sensors and records state variables such as temperature, fill level, and density of the aggregate emulsion. In the present embodiment, the sensor unit 45 includes, in particular, laser sensors, ultrasonic sensors, and capacitance sensors. If the subsoil in front of the drill head requires the addition of aggregate from the aggregate unit 40, a control command, referred to here as the final control signal, is output via the control unit 30. This command sets the final control element 44 into an opening operating state determined by time and flow rate. In the present embodiment, the final control element 44 is also designed as a metering pump with a screw drive.

[0047] A certain amount of aggregate emulsion is thus added to the base emulsion in the emulsion main line 50 and the finished emulsion thus prepared is discharged from the emulsion main line 50 and fed to the drilling rig. Reference symbols used

[0048] 10Base emulsion unit 20Mixing and dosing unit 30Control unit 40Aggregate unit 41Aggregate storage tank 42Preliminary control element 43Aggregate emulsion tank 44Final control element 45Sensor unit 46Temperature control element 40-nAdditional aggregate unit 50Main emulsion line 51Secondary emulsion line 52Bypass control element 60Liquid aggregate unit

Claims

1. Drilling emulsion system, comprising a base emulsion unit (10), a mixing and dosing unit (20), a control unit (30) and an emulsion main line (50), wherein the base emulsion unit (10) is designed to provide a base emulsion and to supply it to the mixing and dosing unit (20) by means of the emulsion main line (50), wherein the mixing and dosing unit (20) is connected to the emulsion main line (50) and has an aggregate unit (40) and an emulsion secondary line (51) and is designed to provide a finished emulsion by admixing an aggregate emulsion to the base emulsion, wherein the aggregate unit (40) has an aggregate storage container (41), a preliminary actuating element (42), an aggregate emulsion container (43) and a final actuating element (44), wherein the aggregate storage container (41) is designed to receive an aggregate, wherein the pre-stage adjusting element (42) is designedto meter the aggregate into the aggregate emulsion container (43), wherein the emulsion secondary line (51) is connected to the emulsion main line (50) and is designed to meter a secondary flow of the base emulsion into the aggregate emulsion container (43) by means of an associated bypass control element (52), wherein the aggregate emulsion container (43) is designed to provide an aggregate emulsion from the aggregate, wherein the final control element (44) is connected to the control unit (30) and is designed to meter the aggregate emulsion into a main flow of the base emulsion, wherein the control unit (30) is designed to provide a final control signal which is designed to control an operating state of the final control element.

2. Drilling emulsion system according to claim 1, characterized by thatthe aggregate emulsion container (43) is assigned a sensor unit (45) which is designed to detect a status value from the group: - fill level - density - viscosity - conductivity - temperature that the sensor unit (45) and the pre-stage control element (42) are connected to the control unit (30) and that the control unit (30) is designed to receive the state value from the sensor unit (45), to process it and to provide a pre-stage control signal which is designed to control an operating state of the pre-stage actuating element and to provide a bypass control signal which is designed to control an operating state of the bypass actuating element.

3. Drilling emulsion system according to one of the preceding claims, characterized by that the additive unit (40) has a tempering element (46).

4. Drilling emulsion system according to one of the preceding claims, characterized by that the mixing and dosing system (20) has a plurality of aggregate units (40-n).

5. Drilling emulsion system according to one of the preceding claims, characterized by that the mixing and dosing system (20) has a liquid aggregate unit (60).

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