RU2244116C1 - Oil extractive device - Google Patents

Abstract

FIELD: oil extractive industry.

SUBSTANCE: device includes exposure chamber, U-shaped branch pipe on it for passing of oil with picking of oil from upwards, made in form of five pipes inserted into one another with common ceiling and bottom and apertures in upper and lower portions of pipe, forming serially placed U-shaped and upturned U-shaped branch-pipe, and channel for passing of water with picking of water from downwards, having common output from device.

EFFECT: higher efficiency.

1 ex, 1 dwg

Description

The invention relates to the oil industry and may find application in field oil and gas gathering systems in fields with highly watered production of producing wells with separate supply of oil and water to the pressure pipeline.

The input device of the well pump is known, containing two inlet pipes, the inputs of which are located at different levels, and their outputs are communicated through a connecting tube. A pipe is connected to the latter, which is an additional channel (RF Patent No. 2123613, class F 04 B 47/00, publ. 1998.12.20).

This solution allows for a clear transition from pumping water to pumping oil only with small flow rates of wells.

The closest to the invention in technical essence is a device for oil production, including a settling chamber, a U-shaped pipe placed in it for oil passage with an oil intake from above and a channel for water passage with a water intake from below, having a common exit from the device (RF Patent No. 2117138, class E 21 B 43/00, publ. 1998.08.10 - prototype).

The known device allows for the additional separation of the oil emulsion into oil and water, to separate mechanical impurities, however, the performance of the device remains low.

The invention solves the problem of ensuring the separation of the oil emulsion into oil and water with a high flow rate of the well.

The problem is solved in that the device for oil production, including a settling chamber, a U-shaped pipe for oil passage with an oil intake from above and a channel for water passage with an intake of water from below, having a common outlet from the device according to the invention, U-shaped pipe for the passage of oil is made in the form of five pipes inserted into one another with a common roof and bottom and holes at the top or bottom of the pipe, forming a successively arranged U-shaped and inverted U-shaped pipe.

The features of the invention are:

1. slop chamber;

2. U-shaped pipe for oil passage with oil intake from above;

3. channel for water passage with water intake from below;

4. general exit from the device;

5. U-shaped pipe for oil passage in the form of five pipes inserted one into another;

6. the same with the common roof and bottom;

7. the same with holes at the top or bottom of the pipe, forming successively arranged U-shaped and inverted U-shaped pipe.

Signs 1-4 are common with the prototype, signs 5-7 are the salient features of the invention.

SUMMARY OF THE INVENTION

When producing waterlogged oil, it is necessary to separate and transport fractions of oil and water separately. Known devices allow you to submit for pumping separated fractions with very small production rates of production wells. With increased flow rates, known devices do not provide a separate supply of oil and water. The separated phases have a very small volume and are easily mixed in pipelines with the formation of an oil emulsion. The proposed device solves the problem of ensuring the separation of the oil emulsion into oil and water with a high flow rate of the well. The problem is solved by the device for oil production, shown in the drawing.

The device for oil production includes a settling chamber 1, five pipes 2-6 inserted into one another with a common roof 7 and a bottom 8 and holes at the top 9 or bottom 10 of the pipes forming a successively arranged U-shaped and inverted U-shaped pipe, and a channel for water passage 11 with water intake from below 12. Pipes 2-6 and a channel for water passage 11 have a common outlet 13 from the settling chamber 1.

The device operates as follows.

The device is installed at the mouth of an oil well. The oil emulsion from the oil producing well is sent to the settling chamber 1. In the settling chamber 1, under the influence of gravitational forces, the oil emulsion is stratified into oil and water. Water as a liquid of higher density occupies a lower position. The accumulation of oil as a liquid of lower density occurs in the upper part. The oil-water interface as oil accumulates decreases to the level of water intake 12 of the channel for water passage 11. When the oil-water interface reaches the level of water intake 12, water drastically displaces oil from pipes 2-6 to outlet 13 from the settling chamber 1. Through holes 9 and 10, oil fills pipes 2-6 and is subsequently expelled from the settling chamber 1 through holes 9 and 10 and pipes 2-6 to the exit 13 from the settling chamber 1. The oil-water interface rises to the level of the hole as the oil is displaced 9. Upon reaching the oil-water interface at the level of the hole 9 there is a sharp displacement of oil by water from the pipes 2-6 in the outlet 13 from the settling chamber 1. Through holes 9 and 10, the water fills the pipes 2-6 and then remains in the pipes 2-6. Water is displaced from the settling chamber 1 through a water intake from below 12 and a channel for water passage 11. The oil – water interface decreases as oil accumulates to the level of water intake 12 of the channel for water passage 11. When the oil-water interface reaches the water intake level 12 the cycle repeats.

The device regulates the sequential supply of either oil or water to the pipeline, which ensures the absence of the formation of a water-oil emulsion.

The ability of the device to function as a locking device for fluid flow is determined by the ratio between the flow rate of the well, the viscosity and density of the well fluids and design features.

Intermediate pipes 3, 4, 5 have holes arranged in such a way that they allow you to change the direction of flow in the opposite direction. Optimal to achieve the task is a fourfold change in flow direction, which is achieved by five pipes, as in the proposed design. Each pair of pipes works as a siphon, and they are connected in series.

Theoretical justification of the possibility of the device

The ability of the device to operate as a locking device for fluid flow is determined by the ratio between the pressure generated by liquids of various densities at its knees at 1 m of its height and the hydraulic friction losses at 4 m of the siphon passage channel (the length of the channel is multiplied by 4, since 1 m siphon corresponds to 4 m of fluid path in four knees). Therefore, there must be a certain ratio between the flow rate of the well, the viscosity and density of the well fluids, as well as the dimensions of the design of the device at which it will prove to be operational.

The difference in hydrostatic pressure in the channels of the siphon per 1 m of its height, ΔР is determined by the formula:

where g is the acceleration of gravity;

ρ _in - the density of the oil-water mixture;

ρ _n - oil density.

Consider the flow of oil through the annular channels of the device. For this case, the average flow rate at a constant flow rate Q is determined by the formula:

where D _VN is the inner diameter of the outer pipe, m (5th pipe),

d _nar - the outer diameter of the inner pipe, m (1st pipe).

The pressure drop per 1 m of the annular space ΔР _Tr due to hydraulic friction is determined by the formula:

Where

coefficient of hydraulic resistance for Newtonian fluid in the laminar flow regime,

Re is the Reynolds number for the flow in the annular channels,

μ _n - oil viscosity (carbonated oil at the pump intake).

Setting the well flow rate in the expression for the Reynolds number shows that the flow in the channels of the device is laminar, which makes it possible to apply formula (4) for the hydraulic resistance coefficient.

Substituting (5) and (2) in (4), we obtain

Substituting (6) into (4), we obtain

Equating (1) and multiply by 4 the value (7), we have:

where from

We multiply by 4 ΔP _tr due to the fact that the fluid passes through the four elbows of the device.

Concrete example

At the wellhead place the proposed device. By means of a borehole pump, production of watered oil is provided. The properties of the extracted products are as follows:

The flow rate of the well is 2.5 m ³ / day.

The water content is 81.78%.

The settling time at 10 ° C without the addition of a reagent is 4 hours.

The density of water is -1.11 g / cm ³ .

The oil density is 0.922 g / cm ³ (there is a high content of residual water due to sedimentation without a reagent).

The viscosity of the oil is 0.0416 Pa · s.

From the manifold line, the watered oil is directed to the settling chamber 1. In the settling chamber 1, the watered oil is separated into oil and water. Through pipes 2-6 and the channel for the passage of water 11, a separate supply of oil and water to the pressure pipe is provided.

In accordance with the calculations according to the formula (9), Q _max = 6.9176 (m ³ / day), which is significantly more than the well flow rate of 2.5 m ³ / day.

The time of separation of the produced products into oil and water, the maximum throughput of the device exceeds the actual flow rate of the well, which ensures a guaranteed supply of either oil or water to the pressure pipe in order to prevent the formation of a highly viscous emulsion.

The application of the proposed device will ensure the separation of the oil emulsion into oil and water with a high flow rate of the well.

Claims (1)

A device for oil production, including a settling chamber, a U-shaped pipe for oil passage with an oil intake from above and a channel for water passage with an intake of water from below, having a common outlet from the device, characterized in that the U-shaped pipe for oil passage made in the form of five pipes inserted into each other with a common roof and bottom and holes at the top or bottom of the pipe, forming a successively arranged U-shaped and inverted U-shaped pipe.