RU2272128C1 - Formation fluid treatment method - Google Patents

Abstract

FIELD: oil production, oil refining, oil chemistry and other fields connected with emulsion breakdown, particularly adapted for formation fluid separation into such components as oil, gas and water.

SUBSTANCE: method involves subjecting formation fluid flow to magnetic treatment to provide emulsified water droplet coalescence; breaking inhibiting shells at oil-water interface to provide additional water droplet collision. To increase rate of water-gas-oil emulsion stratification, to improve quality of emulsion separation into oil, gas and water and to reduce emulsifier consumption above magnetic treatment is carried out in field directed transversely to fluid flow and having strength H = 5-10kA/m and magnetic field strength gradient dH/dr=2-5·10⁶ A/m². Unidirectional unipolar point constant magnets are used for above magnetic field creation. Inhibiting shells are broken with the use of vibration having 10-100 Hz frequency and 0.5-10 mm amplitude.

EFFECT: increased emulsion breakdown rate along with decreased hydrocarbon concentration in water and water content in hydrocarbon, as well as reduced demulsifier consumption.

1 tbl, 2 dwg

Description

The invention relates to the field of oil production, oil refining, petrochemicals and other technical fields related to the destruction of emulsions, and can be used in technological methods for separating formation fluids into components - oil, gas, water.

As is known, the presence of mechanical impurities increases the separation time of water-hydrocarbon mixtures and the content of the hydrocarbon phase in water, as well as the aqueous phase in hydrocarbons, i.e. mechanical impurities play the role of stabilizers [Pozdnyshev GN Stabilization and destruction of emulsions. - M .: Nedra, 1982. - 222 p.]. - Thus, in the preparation of well products, the main task is to remove them from the stream, which facilitates the separation of reservoir fluids into oil, gas, and water components.

A known method of processing well products, including heating it with subsequent destruction of the armor shells at the oil-water interface by a hydrodynamic method in a highly developed turbulent mode. The destruction site of the armor shells is made in the form of a Laval nozzle, where the diameter of the narrow part is determined by hydrodynamic calculation to create a highly developed turbulent flow regime. [RF patent No. 2045982, cl. B 01 D 17/00, B 01 D 19/00, 1995].

The disadvantage of this method is the low efficiency of well production preparation.

Closest to the claimed object is a method of processing well products, including heating with its subsequent processing in a magnetic field for coalescence of emulsified water droplets and the destruction of the armor shells at the oil-water interface for additional merging of water droplets. To create a magnetic field, a magnetic processing installation is used, in which the magnets are mounted in the form of a ring. The destruction site of the armor shells is made with tapering and expanding parts in the form of a cone and with a flow turbulator in the form of a cylinder. [RF patent No. 2149260, cl. E 21 B 43/34, 2000].

The disadvantage of this processing of well products is as follows. When the magnets are arranged in the form of a ring, part of the magnetic flux is closed to the inside of the device through which no fluid flows, as a result of which a magnetic field with a low intensity (1-2 kA / m) is created in the space between the body of the magnetic device and the pipe wall for transporting the well products and a gradient (dH / dr = 1-5 · 10 ³ A / m ² ). Accordingly, the force acting on mechanical impurities in the liquid will also be small.

The invention is aimed at accelerating the separation of emulsions in reservoir fluids while reducing the concentration of hydrocarbons in water and water in hydrocarbons, as well as reducing the consumption of demulsifier.

This is achieved by the fact that in the method for treating formation fluids, including magnetic treatment of the flow of formation fluids for coalescence of emulsified water droplets with subsequent destruction of the armor shells at the oil-water interface to further merge the water droplets, the magnetic treatment is carried out in a direction perpendicular to the fluid flow nonuniform pulsating magnetic field strength H = 5-20 kA / m and a gradient magnetic field strength dH / dr = 2-5 · 10 ⁶ A / m ² by the action directed unipolar n stand point of the magnets and destruction of the armoring shells is effected by vibration impact with frequency fluctuations of 10-100 Hz and an amplitude of oscillation of 0.5-10 mm.

Figure 1 shows the proposed installation for processing formation fluids; figure 2 - block magnetic processing installation.

The installation comprises flanged blocks of magnetic and vibration processing.

The magnetic processing unit is a housing 1, inside of which plates 2 with permanent point magnets 3 mounted on their surface are located parallel to the incoming liquid stream 3. It is advisable to install streamlined guides 4 in front of the plates. The magnets can be made, for example, cylindrical or in the form of a parallelepiped.

The vibration processing unit comprises a diamagnetic housing 5, on the external side of which an electromagnet 6 is mounted. Inside the housing 5, an elastic vibrator plate 7 is fixed.

The method of processing reservoir fluids is as follows.

The field emulsion enters the magnetic processing unit, where under the influence of unipolar directional permanent point magnets a pulsating non-uniform magnetic field with a strength of 5-20 kA / m and a gradient of the magnetic field strength dH / dr = 2-5 · 10 ⁶ A / m ^{2 is created} and the process is initiated demulsification, while the guides 4 direct the fluid flow into the space between the plates 2. During magnetic processing, the bonds of the armor shells are weakened due to the orientation of the asphaltene molecules in the magnetic field, the exit from the shells is ferromagnetic impurities and protsessirovaniya positive and negative ions in opposite directions. Further separation of the emulsion occurs in the vibration processing unit under the action of a vibrator plate 7 oscillating under the influence of an alternating electromagnetic field created by the electromagnet 6 with a frequency of 10-100 Hz and an amplitude of 0.5-10 mm. The vibration field intensifies the process of mass transfer and fusion of oil droplets.

According to the technology described above, the formation fluids of the Ufaneft NGDU with a water content of 70% in a pulsating non-uniform magnetic field of 6000 A / m and a magnetic field gradient of 4 · 10 ⁶ A / m with subsequent vibration exposure were processed (example 1). Formal fluids were subjected to a similar treatment with other parameters (example 2). The source data and results for the examples are summarized in table.

Separation time and quality of reservoir fluids depending on their processing parameters When measures Magnetic field strength, A / m The gradient of the magnetic field, A / m ² frequency Hz Amplitude of vibrations, mm The concentration of demulsifier CPD-005 in oil, mg / DM ³ The time of separation of the emulsion, min The residual concentration of petroleum products in water, mg / l one 6000 4 · 10 ⁶ fifty 5 thirty 25 250 2 8000 5 · 10 ⁶ 47 8 twenty 22 200

For comparison, reservoir fluids were processed according to the prototype using a laboratory model. The field emulsion was first treated with magnets in the form of a ring with a strength of 1 kA / m and a gradient of the magnetic field strength dH / dr = 4 · 10 ³ A / m ² , and then processed with a Laval nozzle. The emulsion separation time was 55 minutes, the residual concentration of oil in water was 850 mg / l.

As can be seen, the use of the invention will allow, in comparison with the prototype, to accelerate the separation of water-gas-oil emulsions by creating a pulsating inhomogeneous magnetic field and at the same time improve the separation of formation fluids into oil, water and gas due to the intensification of mass transfer and the merging of oil droplets (reduce the concentration of oil in water and water in oil). In addition, this will reduce emulsifier consumption.

Claims (1)

A method of treating formation fluids, including magnetic processing of a stream of formation fluids for coalescence of emulsified water droplets with subsequent destruction of the armor shells at the oil-water interface to further merge water droplets, characterized in that the magnetic treatment is carried out in a pulsating nonuniform directional perpendicular to the fluid flow a magnetic field of H = 5-20 kA / m and a gradient magnetic field strength dH / dr = 2-5 · 10 ⁶ A / m ² by the action of a unipolar directed postoja GOVERNMENTAL point magnets and destruction of the armoring shells is effected by vibration impact with frequency fluctuations of 10-100 Hz and an amplitude of oscillation of 0.5-10 mm.

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