EA027796B1 - Liquid - crude oil meter - Google Patents

Abstract

The liquid - crude oil meter is related to the field of measuring equipment and is used for measuring mass flow rate of crude oil and its components. The operating principle of the invention is based on alternate filling with crude oil one of two prismatic ladles arranged in the measuring chamber with weight balancing, the ladles overturning at the moment a definite mass of liquid is reached. The time of filling of measuring chambers defines mass flow rate of the flowing liquid. The liquid meter is provided with a separation unit required for release of gas providing operation in a closed collection system, which serves for elimination of shock wave impact on the ladles and for obtaining a static liquid pouring mode. As a permanent magnet passes the axis of an electromagnetic sensor, the latter forms an electric impulse that is registered by the counter, and filling time count starts, the count stopping after the magnet passes the axis again when the ladle is full. Readings of liquid mass and flow rate are displayed on an indicator, recorded and stored in the archive during a definite time period. In addition, transmission of the normalized impulse into the telemetry system is possible.

Description

The invention relates to the field of measuring equipment and can be used for measuring the mass flow rate of crude oil and its components (oil, produced water).

Known devices and methods for measuring flow, for example, Kremlin P.P. Flow meters and quantity counters. Leningrad., Engineering, 1975; Abramov G.S., Barychev A.V. Practical flow metering in the oil industry. M., OJSC VNIIOENG, 2002.

The disadvantages of these technical solutions are the large error of flow measurements, the complexity and large dimensions of the structures.

Closest to the proposed invention is a mass flow meter, in which the moving system consists of two prismatic chambers of a triangular section, mounted on a swing axis, and adjustable stops that change the angle of inclination of the two-chamber vessel in its original position. Each chamber when filling with liquid is oriented so that the center of gravity of the mass of liquid moves along the bisector of the angle at the apex of the isosceles triangle, which eliminates the error in the measurement of flow rate caused by a change in the density of the liquid (Kremlevsky P.P. Flow meters and quantity counters. Leningr., Engineering, 1975 g.).

The disadvantages of the prototype are the large error of flow measurements, the need to ensure the constancy of the frequency of receipt of the measured doses at different fluid flow rates, the complexity of the design, and the lack of automation of data collection. The aim of the invention is to increase reliability, maintaining the accuracy of flow measurement regardless of the density of the medium being measured, simplifying the design, maintenance and collection of information.

This goal is achieved by the fact that the counter of the amount of liquid - crude oil (hereinafter - SKZH SN) is a chamber-type device with tilting prismatic buckets and load balancers for tipping a mass portion of liquid, equipped with a separation unit.

In FIG. 1 shows a General view of the counter of the amount of liquid crude oil; in FIG. 2 - case; in FIG. 3 - measuring unit.

SKZH - SN consists of the following main units: housing, measuring unit, input collector 3, output collector 4, separation unit.

The casing is a horizontally located cylindrical vessel, on the shell 1 of which, perpendicular to the axis, two coaxial openings are made for the inlet / outlet of the oil and gas mixture through hermetically connected inlet and outlet manifolds 3 and 4, respectively. Moreover, an adjustable input device 6 is installed at the inlet 6. The cover 11 of the measuring unit is attached to the housing through the flange 7 using the ring 8. A gasket, for example, made of rubber, is used to make the connection leakproof. Three threaded holes are made on the inner end of the cover, into which the studs 2 are installed, which serve to fasten the support 12. In addition, shock absorbers 13 are installed on these axes, the movement of which is limited by the washer 14 and cotter pin 15. There are coaxial openings on the end of the cover and the support with bearings, they are installed axis 16 of the measuring unit.

The measuring unit is a movable system and consists of two prismatic buckets 17 of triangular section and side plates 18 to which the load 19 is attached, and one of the plates has two permanent magnets 20.

On the outer end of the cover of the measuring unit, holes are made for attaching electromagnetic sensors 21, density sensor 22, handles 23 and level 24. The holes for attaching electromagnetic sensors are made in such a way that their center coincides with the path of the permanent magnets of the measuring chamber.

The separation unit contains two ejectors 5, mounted on the input and output headers; oil and gas manifold 9, gas manifold 10, interconnecting ejectors and housing SKZH SN; a damper 25 and a funnel 26 installed in the housing. The quencher is a perforated sheet.

The principle of operation of the claimed device is based on the alternate filling with crude oil of one of the two prismatic buckets located in the measuring chamber with cargo balancing and their subsequent tipping over when they reach a certain mass of liquid. The filling time of the measuring chambers determines the mass flow rate of the flowing fluid.

An input manifold and an adjustable input device are designed to enter the working fluid and its output.

The oil and gas mixture is fed into the inlet manifold, then through an adjustable inlet, damper and funnel into the measuring chamber to fill one bucket of the measuring chamber to a value (in mass units), which leads to a change in the condition of stable equilibrium due to the position of the center of mass of the buckets in the measuring chamber, to turn the measuring chamber and drain the liquid from the bucket into the housing SKZH - SN. This process is then repeated on the second camera bucket. At the same time, liquid located in the lower part of the housing is displaced into the output manifold.

A prerequisite for operation in a closed collection system (under overpressure) is

- 1 027796 the presence of gas in the housing SKZH - SN, which is released from the oil and gas mixture when passing through the elements of the separation unit (damper, funnel) due to the effect of gravitational separation. In addition, this unit serves to exclude the action of the shock wave on the buckets and achieve a static loading mode of the mixture. The excess of released gas through the gas collector enters the ejector, then into the output manifold. In addition, to avoid a critical increase in pressure inside the housing, part of the oil and gas mixture is released through the oil and gas manifold into the ejector and enters the inlet manifold.

When a permanent magnet passes through the axis of the electromagnetic sensor, the last electric pulse is generated, fixed by the calculator, and the countdown starts, which stops after the magnet has re-traveled the axis after filling the bucket.

Indications of the mass of liquid and flow rate are displayed on the indicator, and are also recorded and stored for a certain time in the archive. In addition, it is possible to transfer a normalized impulse to a telemetry system:

the density of crude oil and its components under operating conditions;

volume and volumetric flow rate of crude oil under operating conditions;

mass and mass flow of crude oil under operating conditions;

mass and mass flow of crude oil excluding water under operating conditions;

volume and volumetric flow rate of crude oil excluding water under operating conditions;

volume and volume flow of free gas in crude oil under operating conditions;

bringing the calculated values of the volume and volumetric flow rate of crude oil, crude oil excluding water and free gas to standard conditions.

When the data on the content of solids and chloride salts in crude oil is entered into the BV, according to the results of studies of a sample of crude oil in HAL, SKZh-SN, it is possible to calculate the net mass of oil, as well as adjust the net mass of crude oil taking into account the estimate of the amount of crude oil dissolved in it gas.

The dielcometric method (GOST 14203) was chosen as the method for measuring the moisture content of crude oil, which is based on measuring the equivalent dielectric constant of a gas-liquid mixture using a high-frequency electric field created between the electrodes of a capacitive sensor.

where is the percentage of water in the gas-liquid mixture; ε is the dielectric constant of the liquid;

Ώ0, 1 - geometric dimensions of the sensor;

P is the frequency of the electric field.

The principle of operation of the converters is to convert non-electrical quantities (pressure, temperature, physical properties of the medium to be measured) into electrical signals in proportion to the change in non-electrical quantities.

The mass flow rate of crude oil is calculated by the formula

OM \ ¥ П = (Ш ШК) / 1 where Ohm is the mass flow rate of crude oil (liquid phase) of the oil and water mixture; ηΐ is the number of tipping over buckets; tk - the mass of crude oil in the ladle (liquid phase); ί - time of mass flow measurement.

The mass flow rate of oil is calculated by the formula

() mn = [[() mu / n (1 -% \ Y)

The mass flow rate of produced water is calculated by the formula

() mp = ί [ζ) Μ \ νη (% \ Y)

The list of used literature.

1. Kremlin P.P. Flow meters and quantity counters. Leningrad., Engineering, 1975, p. 366371.

2. Abramov G.S., Barychev A.V. Practical flow metering in the oil industry. M., OJSC

VNIIOENG, 2002, p. 361-363.

Claims (2)

CLAIM The counter of the amount of liquid - crude oil, consisting of a housing 1, located in it a block of measuring and input and output headers 3 and 4, characterized in that it is additionally equipped with two ejectors 5, mounted on the input and output headers 3 and 4, oil and gas manifold 9 and a gas manifold 10, as well as a funnel 26, fixed inside the meter body 1 with the coverage of its adjustable input device 6, and installed in the funnel 26 counter to the flow of the mixture into the meter counter by the flow quencher of the mixture 25 in the form of perforators oval sheet, with - 02 0296, this body 1 is a horizontally located cylindrical vessel, on the shell of which, perpendicular to its axis, two coaxial openings are made for the inlet / outlet of the oil and gas mixture, to which the input and output manifolds 3 and 4 are hermetically connected, and an adjustable input device is installed on the inlet 6, and the measuring unit includes a cover 11 attached to the housing 1 through the flange 7 and a support 12, and a rubber gasket 8 is used to impart a tight connection between the housing 1 and the cover 11; two prismatic buckets of triangular section 17, each with its own measuring chamber, formed by the inner surface of the bucket 17, and with its side plates 18 to which the load 19 is attached, two permanent magnets 20 mounted on one of the plates, and on the inner end of the cover 11 made three threaded holes in which the studs 2 are installed, which serve to mount the support 12, in addition, shock absorbers 13 are installed on these studs 2, the movement of which is limited by the washer 14 and cotter pin 15, and at the end of the cover 11 and support 12 coaxial holes with bearings are mounted, the axis of the measuring unit is installed in them, and holes for fastening the electromagnetic sensors 21, density sensor 22, handles 23 and level 24 are made on the outer end of the cover 11 of the measuring unit, while the holes for attaching the electromagnetic sensors 21 are made in this way so that their center coincides with the trajectory of the movement of the permanent magnets 20, and the oil and gas and gas manifolds 9 and 10, the ejectors 5 of the meter and the funnel 26 with the flow quencher 25 form together the meter separation unit.