RU2490419C1 - Device for control of wash liquor density - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: device includes separate lines with stop valves to supply wash liquors with different density; these lines are connected to holding tank and recirculating line with tap; the line can be connected to the unit and provide solution of required density from the holding tank. The line for feeding solution with low density is equipped with additional line with stop valve in order to supply surface-active substance.

EFFECT: simplifying the design and enlarging functional capabilities.

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Description

The invention relates to the oil and gas industry, in particular to devices for controlling the density of washing solutions in the process of their preparation during the repair of wells.

A device for the preparation of aerated drilling and cement slurries (copyright certificate SU No. 685806, IPC 8 E21B 21/06; 21/14 of 09/15/1979), including a housing, a movable nozzle, a nozzle for introducing a working agent, a mixing chamber, a diffuser , a fixed nozzle and a pipe placed under it for introducing an ejecting agent, while a fixed nozzle and a pipe are installed between the mixing chamber and the movable nozzle, thereby improving the quality of preparation of drilling and cement slurries by increasing the amount of ezh ktiruemogo agent.

The disadvantage of this device is that the nozzle for introducing the ejected agent is installed between the mixing chamber and the movable nozzle and feeds the agent directly into the mixing chamber (bypass analogue), which makes it possible to prepare solutions of either reduced density or solutions whose density is equal to the density of the initially prepared solution.

A device for the preparation of cement and flushing solutions (patent RU No. 2206706 IPC 8 E21B 21/06, published in Bulletin No. 17 dated 06/20/2003), including a jet type hydraulic mixer containing a receiving and mixing chamber, a nozzle installed with the possibility regulating the gap in the passageway of the ejector, and a nipple for supplying liquid through the ejector, while it is equipped with averaging tank connected with a hydraulic elevator to the mixing chamber of the hydraulic mixer, and a recirculation line, and is configured to provide a shutter fluid rhenium through the ejector into the receiving chamber with the simultaneous supply of dry powder material into it by simultaneous supply by force or by ejection through the recirculation line and nozzle from the averaging capacity of the solution with a density lower than the calculated one into the hydraulic mixer, and the recirculation line has a tap and is made with the possibility of connection with a unit that ensures selection from a homogenizing capacity of a solution with a density lower than the calculated one and the specified supply through a recirculation line and a nozzle to the hydraulic mixer and overlaps the tap.

The disadvantages of this device are:

- firstly, the complexity of the design, due to the large number of nodes and parts;

- secondly, the design of the device, implemented with the help of this device, does not allow adding surfactants to the washing solution, for example, enriching in the form of a soap solution ML-81B, which improve the washing properties of the liquid.

The objective of the invention is to simplify the design of the device with the possibility of adding to the feed fluid of various surfactants before mixing the wash liquids of different densities.

The problem is solved by a device for regulating the density of the washing solution, including separate lines with locking elements for supplying washing solutions of various densities, connected to the averaging tank, a recirculation line having a tap and made with the ability to connect to the unit, providing selection from the averaging tank of the solution with the required density.

What is new is that the low-density solution supply line is provided with an additional line with a shut-off element for supplying a surfactant.

The figure shows a diagram of a device for controlling the density of the washing solution.

A device for controlling the density of the washing solution includes averaging tank 1 separate lines 2 and 3. Line 2 for supplying a solution with a reduced density is hydraulically connected to an additional line 4 for supplying various additives.

The device also has a recirculation line 5 having a valve 6 and is configured to connect to a pumping unit (not shown in the figure), for example, CA-320, which allows the selection of a solution with the required density from the averaging tank 1.

The device operates as follows.

In the averaging tank 1, first, through line 2, through an open locking element, for example, a gate valve 7, a calculated volume of a liquid of increased density is supplied - ρ _b in a volume of at least 10% of the total required volume - V _{t of the} washing solution.

Then determine the volume of liquid V _m low density ρ _m sufficient to obtain a solution of the desired density - ρ _t and determined by the following dependence:

$$V_m=(V_t\times {\rho }_t-0.1\times V_t\times {\rho }_b)/{\rho }_m,\left(\mathrm{one}\right)$$

where, V _m - volume of liquid of lower density, m ³ ;

V _t - the volume of the solution of the desired density, m ³ ;

0.1 = (10% / 100%) - a coefficient that determines the volumetric ratio of washing liquid of higher density to the total required volume of washing liquid;

ρ _t - the required density of the solution, kg / m ³ ;

ρ _m is the density of a liquid with a reduced density, kg / m ³ ;

ρ _b - the density of the liquid with high density, kg / m ³ .

Then, through line 3 through an open valve 8, a liquid of reduced density is added to the averaging tank 1 - ρ _m in a volume of - V _m calculated according to formula 1, while the valve 6 is closed, located in the recirculation line 5 and at the same time as the solution is supplied to the averaging tank with reduced density through an additional channel 4 serves surface-active substances (surfactants) in the amount of 0.1-0.2% of the required volume - V _t preparation of the washing solution in order to refine the washing liquid. For example, ML-81 is added as a surfactant to improve the flushing properties of the solution.

Next, the valves 7, 8 and 9 are closed and the valve 6 is opened, after which the prepared washing solution of the required density from the averaging tank 1 along the recirculation line 5 for supplying the washing solution of the required density through the open valve 6 is fed into the capacity of the pump unit (not shown in the figure).

After draining the required volume of the washing solution of the required density into the capacity of the pumping unit, the valve 6 on the recirculation line 5 is closed.

An example of a specific implementation:

It is necessary to prepare a washing liquid in a volume of V _t = 10 m ³ with the required density - ρ _t = 1.08 kg / m ³ .

In the averaging tank 1, for example, with a volume of V _E = 20 m ³ , a calculated volume of a liquid of increased density - ρ _b salt water, in which ρ _b = 1.18 kg / m ³ in a volume of at least 10% of the total required volume, is supplied through line 2 - V _{t of} wash solution, i.e. the volume of liquid of increased density V _b is V _b = (10% / 100%) × V _t = 0.1 × 10 m ³ = 1.0 m ³ .

Then determine the volume of liquid of low density - V _m , sufficient to obtain a solution of the desired density - ρ _t = 1,08 kg / m ³ , which is determined by substituting the above values in formula 1:

Then V _m = (10 m ³ × 1.08 kg / m ³ -0.1 × 10 m ³ × 1.18 kg / m ³ ) / 1.00 kg / m ³ = 9.62 m ³ .

Then, through line 3, low density liquid - ρ _m fresh water, in which ρ _m = 1.00 kg / m ³ in a volume of V _m = 9.62 m ^{3 is} supplied to averaging tank 1, while surfactant is added to additional line 4 ML-81 in the amount of:

V _p = (0.15% × 10 m ³ ) / 100% = 0.015 m ³ .

Thus, for the preparation of washing liquid in a volume of V _t = 10 m ³ with the required density ρ _t = 1.08 kg / m ³ , it is necessary to supply the washing liquid 1 through line 2 (salt water in a volume of V _b = 1 m ³ and a density ρ _b = 1.18 kg / m ³ ) and line 3 flushing fluid (fresh water in a volume of V _m = 9.62 m ³ and a density ρ _m = 1.00 kg / m ³ ) and additional line 4 surfactant (ML-81 in the volume of V _p = 0,015 m ³ ).

Similarly, using dependence 1, it is possible to prepare a washing solution in the required volume and the required density in the range ρ _t = 1.00 ....... 1.18 kg / m ³ .

The proposed device for controlling the density of the washing solution has a simple design and allows the addition of various surfactants to the line for supplying a liquid with a reduced density before mixing the washing liquids of different densities in the averaging tank, which extends the functionality of the device.

Claims (1)

A device for adjusting the density of the washing solution, including separate lines with locking elements for supplying washing solutions of various densities, connected to the averaging tank, a recirculation line having a tap and made with the possibility of connection with the unit, providing selection from the averaging tank of the solution with the required density, characterized in that the low density solution supply line is provided with an additional line with a shutoff member for supplying a surfactant .