RU2761455C1 - Separator for wells research - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to a separator for measuring the flow rate and researching oil and gas wells, including a separation tank with a pipeline and a branch pipe for supplying a gas-liquid mixture, pipelines for removing gas, oil and formation water, a vortex tube located in it with a helical cyclone, with a coaxially fixed liner forming an annular gap at the junction with the vortex tube and provided with longitudinal slots. In this case, a part of the pipe and the liner are placed in a baffle casing, in addition, the separation tank contains a vertical coalescing droplet separator, a coalescer for breaking the water emulsion and a vertical overflow baffle, as well as a gas purification filter installed on a horizontal plate placed in a vertical bell. Wherein the filter is replaceable. The separator is characterized by the fact that the gas-liquid mixture supply pipeline in front of the separation tank branches into two parallel pipelines, each of which is connected to one of the two vortex tubes through the gas-liquid mixture supply pipe, while the vortex tubes are replaceable in diameter, and the cyclones - in diameter and pitch helical line.

EFFECT: separator ensures the quality of separation in a wide range of well flow rates while reducing the size of the unit to a size that allows it to be used in small-sized mobile units.

2 cl, 3 dwg

Description

The invention relates to the oil and gas industry and can be used to measure the flow rate and study oil and gas wells during their development after drilling and during operation.

A separator is known, consisting of an inlet first tubular element, a gas-liquid mixture (GZHM) inlet pipe, gas and separated liquid outlet pipes, and a liquid sump. The first tubular element contains a mixer, a swirler, a second tubular element and an anti-vortex device. The second tubular element is provided with through holes and is installed coaxially with the first tubular element, so that an annular gap is formed between the outer surface of the second tubular element and the inner surface of the first tubular element. The first tubular element is connected to a liquid sump through a recirculation line and a connecting unit (US Pat. WO 2014/060048, cl. B01D 17/02, B01D 45/16, B04C 3/06, 19.10.2012).

The disadvantage of the device is that in the first component, a rotational motion is created with the formation of an annular liquid layer, and in the second, a residual rotational motion is used also with the formation of an annular layer on the cylindrical wall of the first tubular element and a central gas flow with a reduced amount of accumulated liquid. As the author notes, there is a lack of a clear boundary between the annular layer and the central sweat of the gas, that is, it is assumed in advance that even with two-stage separation, high quality gas purification is not ensured. Another disadvantage is the vertical configuration of the container for collecting liquid, which increases the dimensions of the installation, as well as the separation of the container by a partition, which entails the need to regulate the liquid level in each compartment and complicate the control system. In this connection, the device is limited for use in test installations.

Known separator containing a cylindrical body with coaxially installed inside the body inlet and outlet pipes, a swirler, a disperser of liquid plugs in the form of wall spiral plates. The inlet pipe for the mixture passes into the expansion chamber with a diffuser and a confuser, the beginning and end of the inlet pipe are made conoidal, and the beginning of the pipe is located in the confuser of the expansion chamber. An intermediate pipe is installed between the inlet and outlet pipes, in the wall of which there are successively located tangential, longitudinal and annular slots. Stabilizers in the form of coaxial pipes are placed around these slots. Liquid outlet pipes are installed in the expansion chamber and behind the expansion chamber (US Pat. RU 2260467, class B01D 19/00, 03/02/2004).

The disadvantage of the device is the uncontrolled discharge of gas from the inlet chamber, depending on the liquid content, as well as a violation of the circulation of gas with dropping liquid when the load is reduced. The two-chamber device of the separator increases the dimensions of the unit, which prevents its mobile use.

Known separator containing a housing with a pipe for inlet gas and liquid mixture and pipes for the outlet of purified gas and liquid, located in the body of the gas distribution device, above which there is a plate with direct-flow centrifugal separation elements. Above this plate is a combined separation and filtration section, made in the form of two plates installed one above the other, the upper of which contains coalescing filter elements, each of which is made of alternating coalescing and drainage layers of filter material, and drain pipes for removing liquid flowing from the outer surface of the filter elements. The lower plate contains gas supply pipes directly inside the filter elements of the upper plate, and the gas supply pipes are made coaxially with a gap relative to the filter elements for additional drainage through the annular gap formed by the inner diameter of the filter elements and the outer diameter of the gas supply pipes to the filter elements of liquid flowing from the inner surface of the filter elements, and drain pipes for draining this liquid (US Pat. RU 2729572, cl. B01D 45/12, B01D 46/24, B01D 53/26, 07/23/2019).

The disadvantage of the device is the lack of maintainability of pre-assembled microcyclones and filter elements without the possibility of changing their number and size to control performance.

The closest to the claimed installation is a tubular preliminary separation device containing an ascending section of the pipeline and a chamber for preliminary sedimentation of a liquid, a gas-oil mixture supply pipe, gas and separated liquid outlet pipes connected to a gas-liquid separator. A bundle of pipes is located in the ascending pipeline. The chamber for preliminary sedimentation of the liquid contains sequentially placed in it vertical louvred plates, a central pipe with a confuser and a swirler, and an outlet pipe. Parallel longitudinal slots are made on the surface of the central tube. The central and outlet pipes are separated by an annular slot with opposing cones (US Pat. RU 2292227, class B01D 19/00, 05/08/2005).

The disadvantage of the device, selected as a prototype, is the likelihood of secondary entrainment of the trapped liquid due to the imbalance in the operation of the drain pipes - hydraulic locks with pulsation of the flow rate of gas liquids in a wide range of well flow rates. Also, the disadvantage can be attributed to the two-chamber design of the device, which increases its dimensions and prevents mobile design.

A common disadvantage of the known analogs is unsatisfactory operation in a wide range of varying well flow rates, as well as the lack of operational adaptation and the possibility of optimization in the research process. The specified ranges of performance of test separators are very wide and in some cases can change tens of times, therefore, to optimize them, it is necessary to adapt the separators to these conditions.

The technical result of the invention is to ensure the quality of separation in a wide range of well flow rates while reducing the size of the unit to a size that allows it to be used in small-sized mobile units (PKIOS).

The specified technical result is achieved by the fact that in a separator for measuring the flow rate and researching oil and gas wells, including a separation tank with a pipeline and a gas supply pipe, gas, oil and formation water discharge pipelines, a vortex tube with a helical cyclone located in it, with coaxially fixed a shank forming an annular gap at the junction with the vortex tube and equipped with longitudinal slots, while part of the pipe and the shank are placed in a baffle casing, in addition, the separation tank has a vertical coalescing droplet separator, a coalescer for breaking the water emulsion and a vertical overflow baffle, as well as a filter for gas purification, installed on a horizontal plate placed in a vertical bell, unlike the prototype, the gas supply pipeline in front of the separation tank branches into two parallel pipelines, each of which is connected to one of two vortex pipes through the gas supply inlet pipe, while the vortex pipes the pipes are replaceable in diameter, and the cyclones in diameter and pitch of the helical line, in addition, the filter for gas purification can be replaced by a group of filters of a smaller diameter, but with a larger total filtration area.

The proposed technical solution has a significant difference from the known ones, which consists in the stepwise division of the entire operating range into 2 intervals using a double input: with one vortex tube by 50% of the design load, with two tubes - by 100%, which makes it possible to improve the quality of separation in a reduced range of liquid and gas loads. The second important significant difference of the installation is the possibility of prompt replacement of vortex tubes and filters with standard sizes with optimal characteristics, which allows creating narrower new ranges within the specified project.

FIG. 1 shows a separator with one filter.

FIG. 2 is a left side view of FIG. 1 along line A shown in FIG. one.

FIG. 3 shows a partial top view of a separator with a group of filters.

The installation contains a separation tank 1, to which the gas supply pipeline 2 and gas discharge pipelines 3, oil 4 and formation water 5 with measuring 6 and control devices are connected 7. The gas supply pipeline 2, in front of the tank 1, branches into two parallel pipelines, each of which is connected to one of the two vortex tubes 9 through the GZhS inlet pipe 9. Pipes 9 are located parallel to the tank 1 and each of them is equipped with a helical cyclone 10. To expand the working range when changing the operating modes of the separator, the vortex tube 9 and the helical cyclone 10 are replaceable. Depending on the productivity of the investigated well, pipe 9 can have different diameters, for example, 4 '', 6 '' and 8 '' inches, and cyclone 10 - the diameter and pitch of the helical line to change the flow rate in the screw channel, providing phase separation in the centrifugal field ... Coaxially with the pipe 9, the shank 11 is fixed with longitudinal slots 12, so that an annular gap is formed between them. emulsions 16, overflow baffle 17 and level gauges 18. The filter for gas purification 19 is located on a horizontal plate 20, located in a vertical bell 21. A hydraulic seal pipe 22 is connected to the bottom of the horizontal plate 20. To expand the working range when changing the operating modes of the separator, the filter 19 is made replaceable ... As the load increases, the filter 19 is replaced by a group of filters 19 of a smaller diameter, but with a larger filtration area. Depending on the productivity of the investigated well, the selection of material, diameter, height and number of filters is carried out.

The calculation of the diameter, height and number of filters 19 is carried out according to the formula:

where K is the brevity of increasing the filter area;

d is the diameter of the filter in the case of group placement in the dimensions of the cap;

D is the diameter of one filter in the dimensions of the hood;

n is the number of filters with diameter d;

h _1,2 - the height of the filters taken in the calculations.

For example, in a separation plant one filter with a diameter of 400 mm can be replaced with 6 filters with a diameter of 125 mm, while the filtration area is doubled.

The installation works as follows.

The production of the investigated well is GZhS: gas, oil (gas condensate), formation water through the supply pipeline 1 is bifurcated into two streams and through the nozzles 8 it enters the vortex tubes 9. In the vortex tubes 9, the GZhS is separated due to centrifugal forces created by the helical cyclone 10 into two parts - gas and liquid. The liquid part (oil-water) is collected on the inner surface of the vortex tube 9, under the action of a rotating gas vortex moves along the pipe wall and through the annular gap 13 and longitudinal slots 12 is thrown out with a part of the gas into the space of the baffle casing 14, designed to organize the exit of liquid and gas into the settling zone of the tank 1. In the settling zone, the liquid is stratified into two parts with the help of the coalescer 16 and the overflow partition 17: the water part before the partition 17 and the oil part after the partition 17, which are removed from the tank by pipelines 5 and 4, respectively. To control and regulate the process of liquid separation, the level of oil and formation water is measured using level gauges 18.

Gas containing not captured in vortex tubes 9 liquid particles and mechanical impurities, after leaving the baffle casing 14 is directed to the gas zone of the separator and undergoes additional cleaning in a vertical coalescing droplet separator 15, and then final cleaning in a filter or a group of filters 19. Liquid captured by the filter or a group of filters 19, accumulates on the horizontal plate 20 and flows through the hydraulic lock pipe 22 into the settling zone of the tank 1, and the cleaned gas is discharged into the pipeline 3.

The purified gas, oil and formation water, after being discharged into the corresponding pipeline, pass through the measuring 6 and regulating devices 7.

The proposed separator is in demand for the development and research of oil and gas wells after their drilling and during operation.

Claims (2)

1. A separator for measuring the flow rate and researching oil and gas wells, including a separation tank with a pipeline and a branch pipe for supplying a gas-liquid mixture, pipelines for removing gas, oil and formation water, a vortex tube with a helical cyclone located in it, with a coaxially fixed liner forming an annular gap at the junction with the vortex tube and equipped with longitudinal slots, while part of the pipe and the liner are placed in a baffle casing, in addition, the separation tank has a vertical coalescing droplet separator, a coalescer for breaking the water emulsion and a vertical overflow baffle, as well as a gas purification filter installed on a horizontal plate placed in a vertical bell, while the filter is replaceable, characterized in that the gas-liquid mixture supply pipeline in front of the separation tank branches into two parallel pipelines, each of which is connected through a gas-liquid mixture supply pipe to one of the two vortices outlet pipes, while the vortex tubes are replaceable in diameter, and cyclones - in diameter and pitch of the helix. 2. A separator according to claim 1, characterized in that the filter is replaced by a group of replaceable filters of a smaller diameter, but with a larger total filtration area.

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