RU2783466C1 - Complex for the preparation of emulsion drilling muds on a hydrocarbon basis and the method for its operation - Google Patents

Abstract

FIELD: mining industry.

SUBSTANCE: group of inventions relates to the preparation of emulsion drilling muds on a hydrocarbon basis. The complex for the preparation of emulsion drilling mud on a hydrocarbon basis contains the initial and working tanks, ejector, pumps, cleaning system, supply lines of the treated mud connected to a dispersant containing carbide cone-shaped nozzles and a drain pipe. The turbine shaft is located inside the dispersant, turbine shaft stators and rotors are installed. The inner cylindrical cavity of the turbine shaft is connected by channels running across the shaft to the turbine output chamber: two channels in one cross section and two channels in another cross section. The turbine shaft is connected to a hollow head, on the body and the end part of which there are holes with threaded connections, into which carbide cone-shaped nozzles are installed, directed at each other and rotated relative to each other to collide with oncoming jets at an angle of 45°-90°. The inner cylindrical cavity of the turbine shaft is connected to the dispersion chamber and drain pipe through holes and carbide cone-shaped nozzles of the hollow head. The initial tank with a hydrocarbon base through the sequentially installed ejector, pump and dispersant is connected to the storage tank, which is simultaneously connected to a container with a dispersion medium through a second pump and dispersant. The dispersant, in turn, is connected to the working tank, which is connected through the third pump to the well connected to the cleaning system, which is connected to the working capacity.

EFFECT: increase in efficiency and the possibility of completely eliminating the formation of an explosive and flammable environment during the preparation of an emulsion drilling mud.

2 cl, 3 dwg

Description

The invention relates to the oil and gas industry, in particular to methods and devices for the preparation of oil-based emulsion solutions (OBM) used in well drilling.

There is a problem of the occurrence of static electricity charges, spark discharges and explosive concentrations of vapor-air mixtures during spraying, deformation, crushing and relative movement of the components of the ERWM mixture, which leads to ignition, explosion and fire at hazardous production facilities.

A known installation [SU 323540, IPC E21V 21/00, 1972] for the preparation of washing liquids in order to provide the possibility of periodic loading during continuous operation, made in the form of two front-mounted milling jet mills - a receiving and a drain, and in the receiving mill the volume of the working the chambers are larger, for example, three times larger than in the drain, and in the upper part they are connected by a sealed pipe driven by one internal combustion engine.

Also known is a device for the preparation and processing of drilling fluids, made in the form of a milling jet mill [SU 1159629, IPC V02S 13/06, 1985], including a housing, a hopper, a bladed rotor, a dispersing plate, a trap, an outlet grate, a drain a tray and a supply pipe with a longitudinal slot made with an extension from the pipe inlet to its opposite end.

The disadvantages of analogues is the low productivity and efficiency of the described devices.

The closest in technical essence, taken by the authors as a prototype, is the device of the hydraulic disperser DG-40 [according to the site https://www.spmi.ru/sites/default/files/imci_images/sciens/dissertacii/2020/koval_dissertaciya.pdf, found on October 08, 2021], containing a body, inlet pipes at the ends of which hard-alloy cone-shaped nozzles are mounted and located coaxially, a working chamber, a line for supplying a working fluid, a drain pipe.

The disadvantage of the prototype is the low productivity for the preparation of the drilling fluid, as well as the need to install hydraulic and mechanical mixers in the receiving tanks of the circulation system to ensure uniform distribution of the components of the drilling fluid and prevent its stratification. Such a circulation system does not provide sufficient tightness, which increases the risk of static electricity charges, sparks and explosive concentrations of vapour-air mixtures. Ingress of atmospheric oxygen into the drilling fluid requires subsequent obligatory degassing, which reduces the energy efficiency of the device and the process as a whole.

A known method of obtaining an invert-emulsion drilling fluid based on a water-based drilling fluid [Ilyin G.A. et al. Transformation of a clay solution into an invert emulsion. Express information VNIIEGazprom, ser. Geology, drilling and development of gas fields, 1986, no. 16.], which consists in creating a direct emulsion with continuous circulation of a water-based clay solution with its subsequent enrichment with diesel fuel, bitumen and special additives, for example, SMAD. At the same time, a hydrocarbon phase is prepared, containing an emulsifier and the remaining part of the calculated amount of diesel fuel, SMAD and bitumen. The prepared hydrocarbon phase is mixed with the circulating slurry until it is converted into an invert emulsion due to the inversion of the emulsion phases (reversal of the direct emulsion). The invert-emulsion drilling fluid obtained by the specified known method contains, as an aqueous phase, water or a water-based clay drilling fluid, and as a hydrocarbon phase, a mixture of diesel fuel or oil with oxidized bitumen, SMAD-1 and Emultal in the following ratio of components, weight . %: water or water-based mud - 28.5-54; diesel fuel or oil - 40-60; highly oxidized bitumen - 2.0-4.5; SMAD-1 2.0-4.0; Emultal - 2.0-3.0.

A disadvantage of the well-known technology for the preparation of drilling mud, obtained from a clay drilling mud on a water basis by the method of phase inversion, is the multi-stage and laborious preparation process, including the conversion of the clay mud into a direct emulsion. In addition, the drilling fluid preparation process itself can lead to static electricity charges, sparks and explosive concentrations of vapour-air mixtures.

The prototype of the invention is a method for preparing a hydrocarbon-based drilling fluid for drilling wells with abnormally low reservoir pressure [RU 2635405, IPC C09K 8/38, 2017], including mixing a gelling agent with a hydrocarbon liquid, for example in the form of oil, at 600-1500 rpm until an emulsion composition is obtained, followed by the generation of aphrons by adding an aphron-forming surfactant to the resulting mixture, and then the resulting mixture is dispersed by exposure to high shear stresses and cavitation using a high-speed mixer of the Hamilton Beach type, providing a rotation speed of at least 9000 rpm, or by means of field equipment in the form of hydraulic funnels of jet and vortex types RSD / SLQ-200, HJM-200, RSD / XLQ-250, HVM-250, or hydraulic dispersers of the DShM-100 DG-2, DGS brands -40-20, or their analogues, providing a capacity of 50÷600 m ³ / h at an inlet pressure of 0.2 ÷10 MPa, and after the specified dispersion, a lightening additive is additionally introduced into the mixture, in the form of aluminosilicate microspheres or glass microspheres, or polymer microspheres, or perlite, or vermiculite, or wood flour, in a two-stage mixing mode: 600-1500 rpm for 10-30 minutes at the first stage and subsequent dispersion of the resulting solution at a rotation speed of 1500-2500 rpm for 15-60 minutes at the second stage, while finely dispersed amorphous silicon dioxide or an aqueous solution of a mixture of saponified fatty acids is used as a gelling agent , or a mixture of them.

The disadvantage of the invention is that during the preparation of the drilling fluid, charges of static electricity, sparks and explosive concentrations of vapor-air mixtures can occur. In addition, the preparation of ERUO by the above method is a rather laborious, material-intensive process, involving the use of an additional number of electric motors, agitators and pumping equipment.

The objective of the invention is to increase the productivity of the complex for the preparation of drilling fluid, taking into account the provision of the required quality of grinding, while maintaining sufficient tightness.

The problem is solved by the fact that in the complex for the preparation of an emulsion drilling fluid on a hydrocarbon basis, containing the initial and working tanks, an ejector, pumps, a cleaning system, a line for supplying a treated solution, connected to a dispersant containing hard-alloy cone nozzles and a drain pipe, according to the invention, inside disperser, the turbine shaft is located, stators and rotors of the turbine shaft are installed, the inner cylindrical cavity of the turbine shaft is connected with the turbine outlet chamber by channels running across the shaft: two channels in one cross section and two channels in another cross section, the turbine shaft is connected to a hollow head, on the body and the end part of which there are holes with threaded connections, in which hard-alloy cone-shaped nozzles are installed, directed at each other and rotated relative to each other for collision of oncoming jets at an angle of 45 ° ÷ 90 °, the inner cylindrical cavity of the turbine shaft through the holes and firmly alloyed cone-shaped nozzles of the hollow head are connected to the dispersion chamber and the drain pipe, the initial container with the hydrocarbon base is connected to the storage tank through the ejector, pump and disperser installed in series, which is simultaneously connected to the container with the dispersion medium through the second pump and the disperser, the disperser, in turn, is connected with a working tank, which is connected through the third pump to the well, which is in communication with the cleaning system, which is connected to the working tank.

The problem is solved by the fact that in the method for preparing an emulsion drilling fluid on a hydrocarbon basis, including mixing a hydrocarbon base, an aqueous phase and a surfactant, dispersion of the resulting mixture with stirring, according to the invention, the method uses the aforementioned complex for preparing an emulsion drilling fluid on a hydrocarbon basis, the dispersion is carried out in two stages: at the first stage, after supplying the hydrocarbon base from the original container and adding surfactants through the ejector, they are mixed in the disperser by feeding them to the shaft through the system of stator and rotor blades, and then under a pressure of 4 ÷ 6 MPa at a speed of 1200 -1450 rpm into a rotating hollow head with hard-alloy cone nozzles, passing through which the flow exits in the form of oncoming jets at an angle of 45°÷90°, then the mixture of the hydrocarbon base and surfactant is sent to the storage tank, at the second stage the mixture of the hydrocarbon base and surfactant send about into the disperser, where it is mixed with the flow of the aqueous phase supplied from the container with the dispersion medium, and dispersion is carried out, while the feed rate into the rotating hollow head is the same as in the first stage, and the pressure is 8–10 MPa, the resulting emulsion is sent to the working tank, and from the working tank it is pumped to the well, from where it flows back to the cleaning system, then back to the working tank, thus forming a closed working cycle.

The technical result of the invention is to increase the safety and efficiency of the method for preparing oil-based emulsion drilling fluids by eliminating the possibility of the formation of static electricity charges and the access of oxygen in the composition of atmospheric air to the ERAD, and as a result of eliminating the fire and explosion hazardous properties of the oil-based emulsion solution, achieving electrical stability of 280 B, as well as by reducing the time spent on the preparation of drilling fluids, taking into account the required quality of grinding of their initial components.

The essence of the claimed complex and method is illustrated by graphic materials, on which:

in fig. 1 schematically depicts a dispersant for preparing a drilling fluid;

in fig. 2 shows a diagram of the implementation of the 1st stage method and FIG. 3 of the second stage of drilling mud preparation.

The complex for the preparation of an emulsion drilling fluid on a hydrocarbon basis, contains the original 20, storage 19, working 33 tanks and a tank 31 with a dispersion medium, an ejector 21, pumps 24, 30, 34, a cleaning system 35, as well as lines for supplying the treated solution connected to dispersant 28 (Fig. 2, 3). The initial container 20 with a hydrocarbon base is connected through the ejector 21, the pump 24 and the disperser 28 in series with the storage container 19, which is simultaneously connected to the container 31 with the dispersion medium through the second pump 30 and the disperser 28, the disperser 28, in turn, is connected to the working container 33 , which is connected through the third pump 34 to the well 36, which is connected to the cleaning system 35, which is connected to the working tank. The disperser (Fig. 1) consists of the following elements: threaded connections 1, 17 for connection to the piping system, sub 2, disperser housing 4 and shaft 5. Turbine stators 6 are installed in housing 4, turbine shaft rotors 7 are installed on shaft 5. The parts mounted on the shaft 5 of the turbine are fixed due to axial compression with their nut 3. The parts installed in the housing 4 are also fixed due to axial compression with the help of a sub 2. The shaft 5 is centered in the housing 4 by radial supports 8, and at the outlet of the housing 4 is centered by the nipple 12. The axial support 10 of the shaft 5 is installed closer to the exit from the housing 4.

The inner cylindrical cavity d of the turbine shaft 5 is connected by channels s running across the shaft 5 to the outlet chamber of the turbine g: two channels s in one cross section and two channels s in another cross section. The place of the channels s is blocked by a spacer sleeve 9, in which grooves similar to the channels s are made, as well as matching them along the flow section. The shaft 5 of the turbine is connected by means of a working sub 13 with a hollow head 16, on the body and end part of which there are holes with threaded connections, in which hard-alloy cone-shaped nozzles 15 are installed, directed at each other and rotated relative to each other to collide with oncoming jets at an angle of 45 °÷90°. The inner cylindrical cavity of the shaft 5 of the turbine through the holes and hard-alloy cone nozzles 15 of the hollow head 16 is connected to the dispersion chamber w and the drain pipe 18. The dispersion chamber w is limited by the inner surface of the housing 14, mounted on the housing 4 of the disperser.

The method is implemented as follows. At the first stage, the required amount of the hydrocarbon base from the original tank 20 after opening the valve 22 is sent to the pumping unit 24 through the pipeline, in which surfactants are introduced through the ejector 21 (Fig. 2). Next, the hydrocarbon mixture through a pre-open valve 25 under pressure is directed through the tee 26 to the disperser 28, for example, with a diameter of 240 mm, in which the dispersed fluid flow is directed to the shaft 5, passing through the blade system of the stators 6 and rotors 7 of the turbine shaft, and then under pressure 4 ÷6 MPa the mixture enters the head 16 rotating at a speed of 1200-1450 rpm with hard-alloy cone nozzles of a certain diameter (Fig. 1). Passing through the cone-shaped nozzles, the flow exits in the form of counter jets at an angle of 45°÷90°, which ensures their counter impact at a speed of 70-80 m/s during rotation of the shaft 5. Then the mixture enters the dispersion chamber w, where intensive mixing of reagents with hydrocarbon base, from where it exits through the pipeline through an open valve 29 in the form of a mixture of the hydrocarbon base into the storage tank 19, to accumulate the required volume of the hydrocarbon base with surfactant (Fig. 2). At the second stage, when the valve 27 is opened, the mixture of the hydrocarbon base and the surfactant is sent from the storage tank 19 through the pump 30 back to the disperser 28, where it is mixed, with the flow of the aqueous phase supplied from the tank with the dispersion medium 31, in the ratio 70/30 . The feed rate into the rotating hollow head of the disperser 28 is the same as in the first stage, and the pressure is 8÷10 MPa (Fig. 3). During the implementation of the second stage of mixing the mixture, valves 22 and 29 (Fig. 2) are in the closed position. Further (Fig. 3), after opening the valve 32, the resulting emulsion is sent to the working tank 33 with a capacity of about 30-55 l / s, from where the pump 34 through the drilling tool (not shown in Fig. 3) the mixture is sent to the well 36, from where it is sent back to the cleaning system 35, then back to the working tank 33, thus forming a closed working cycle.

The proposed technology makes it possible to prepare a working emulsion in a few hours in the volume required for supply to the well in just one cycle of the installation, this eliminates the overflow, topping up the finished emulsion into a container to the required volume, for subsequent supply to the well. There is an increase in the quality indicators of the resulting ERUO, by ensuring the tightness and closure of the system for the preparation of the ERUO by the proposed complex and the method of its application, the reduction of the stages of the technological process for preparing the hydrocarbon-based emulsion due to the absence of the need for degassing the finished emulsion and thus eliminating the formation of an explosive and flammable environment.

Claims (2)

1. A complex for the preparation of an emulsion drilling fluid on a hydrocarbon basis, containing an initial and a working tank, an ejector, pumps, a cleaning system, a supply line for the treated solution, connected to a disperser containing hard-alloy cone nozzles and a drain pipe, characterized in that a shaft is located inside the disperser turbine, stators and rotors of the turbine shaft are installed, the inner cylindrical cavity of the turbine shaft is connected to the outlet chamber of the turbine by channels running across the shaft: two channels in one cross section and two channels in another cross section, the turbine shaft is connected to a hollow head, on the housing and the end part of which there are holes with threaded connections, in which hard-alloy cone nozzles are installed, directed at each other and rotated relative to each other for collision of oncoming jets at an angle of 45 ° -90 °, the inner cylindrical cavity of the turbine shaft through the holes and hard-alloy cone nozzles The hollow head nozzle is connected to the dispersion chamber and the drain pipe, the original container with the hydrocarbon base is connected to the storage tank through a series-installed ejector, pump and disperser, which is simultaneously connected to the container with the dispersion medium through the second pump and the disperser, the disperser, in turn, is connected with a working tank, which is connected through the third pump to the well, which is in communication with the cleaning system, which is connected to the working tank. 2. A method for preparing an oil-based emulsion drilling fluid, including mixing a hydrocarbon base, an aqueous phase and a surfactant, dispersing the resulting mixture with stirring, characterized in that the method uses a complex for preparing an oil-based emulsion drilling fluid according to claim 2. 1, the dispersion is carried out in two stages: at the first stage, after the hydrocarbon base is supplied from the original tank and the surfactant is added through the ejector, they are mixed in the disperser by feeding to the shaft through the system of stator and rotor blades, and then under a pressure of 4-6 MPa at a speed of 1200 -1450 rpm into a rotating hollow head with hard-alloy cone nozzles, passing through which the flow exits in the form of oncoming jets at an angle of 45°-90°, then the mixture of the hydrocarbon base and surfactant is sent to the storage tank, at the second stage the mixture of the hydrocarbon base and surfactant sent back to the disperser, where they are mixed with the flow of the aqueous phase supplied from the container with the dispersion medium, and dispersion is carried out, while the feed rate to the rotating hollow head is the same as in the first stage, and the pressure is 8-10 MPa, the resulting emulsion is sent to the working container, and from the working tank is pumped to the well, from where it flows back into the cleaning system, then back to the working tank, thus forming a closed working cycle.

Images