SU1666923A1 - Method of automatic metering petroleum flow rate and device thereof - Google Patents

Abstract

The invention relates to the extraction of oil and can be used in the oil and petrochemical industry. The aim of the invention is to improve measurement accuracy and enhance functionality by measuring the flow rate of oil and produced water. At the beginning of the cycle, the actuator 2 is opened and the well through line 1 is connected to the measuring separator 3 and at the same time the timer is turned on. The oil liquid begins to drain to the level H, at which the alarm 10 is triggered, the actuator 2 closes and the timer turns off. A signal proportional to the differential pressure generated at the same heights and piezometric columns of antifreeze and oil liquid comes from the output of the differential pressure gauge into control unit 7, and taking into account the density of produced water and oil, the values of daily weight flow rate of oil and produced water are calculated. The result is registered in the registration unit 21. 2 sp.f-ly, 1 ill.

Description

The invention relates to the extraction of oil and can be used in the oil and petrochemical industry.

The purpose of the invention is to increase the measurement accuracy and enhance the functionality by measuring the flow rate of oil and produced water.

The drawing shows the device (system) implementation of the method.

Oil to liquid (LC) from a well (not shown) containing produced water, oil and gas, through line 1 through diaphragm 2 enters measuring separator 3, where it is separated into gas and liquid phases. The gas phase from the upper part of the separator 3 through the pipeline 4 in parallel flows into the upper part of the cylindrical vertical tank 5 and the common collector 6, and the liquid phase accumulates in the separator. The moment of entering the separator into the separator is determined on the control unit 7. When the separator is filled, the actuator (MI) 8 installed in the pressure take-off line in the negative chamber of the differential pressure gauge 9 is closed. When the NL level in the separator reaches a predetermined height h, the control unit 7 closes the filling line MI 2 and opens the MI 8 pressure selection using the contactless level indicator 10 level signal. After this, a measurement cycle begins, consisting in measuring the differential pressure in differential pressure gauge 9 with a negative chamber through a separating vessel 11 connected to a sensor 12 installed at the bottom of the separator, and with a positive camera through a separating vessel 13 to a sensor 14 installed at the bottom part of the tank 5, according to the measured value, which from the output of the differential pressure gauge 9 enters block 7, and taking into account the water densities of the water source and oil p. manually entered, according to the calculation formulas, the weight flow rate of the NC, oil and produced water is determined in block 7. Moreover, the tank 5 in advance through lines 15 and the open valve 16, the closed valves 17 and 18 are filled with water with a certain density PB (R p). After the tank is filled, the valve 16 is closed and the valve 17 is opened. At the same time, the water level in the tank 5 through line 19 is set equal to the height h. The measurement results are output to the registration unit 20. After measuring the signal from block 7, IM 8 is opened and the NJ starts to drain from separator 3 to collector 6. The end of the discharge is determined from information received from differential pressure gauge 21 with a negative chamber through a separation vessel 22 connected to sensor 23 located at the bottom of the separator, above at some distance from the sensor 12, and with the positive chamber through the separation vessel 24 with the sensor 12. The ambient temperature is measured by the sensor connected to block 7.

The formula developed for this method and defining the water content of an LC is derived as follows.

For binary systems, which is an NL, the density is determined by the subsequent analytical expression

p „w Op + (1 - Orn

This expression can be written as follows

Breast cancer or + (1 -a) pH + ЈA -l.

Multiplying both sides of the equality by gh, after the corresponding transformations we get

RA -rn gh (pA -rnzh PB-PH gh (pB-ru)

RA -PH1 dr

RV -rn dp (rv -rn)

The principle of operation of the method shown in the drawing is as follows.

Initially, through line 15 through the open valve 16, tank 5 is filled with antifreeze density PA. When the tank is filled, the valves 17 and 18 are closed and the tank is under atmospheric pressure. After filling the container, the valve 16 is closed, and the valve 17 is opened. In this case, excess antifreeze is higher than h due to its hydrostatic pressure through line 19 and pipeline 4 is poured into manifold 6.

The lower part of the container is connected to the positive chamber of the differential pressure gauge by means of a separating liquid, and the valve in the line of the positive chamber (not shown) is closed. At the beginning of the cycle, a single signal 1 produced by block 7 opens the actuator 2 and the well via line 1 is connected to the measuring separator 3 and the timer is simultaneously activated. Drain NJ begins. At the same time, IM 8 and 2 are closed. When the NC level in the separator 3 reaches the h mark, the clock mechanism is closed by the signal of the level 10 levelless alarm device. 2. The clock mechanism turns off. According to the survey, a signal proportional to the pressure drop created at the same heights h by the piezometric pillars of antifreeze in the tank 5 and the oil fluid in the separator, from the output of the differential pressure gauge enters block 7 and taking into account the values of the density of formation water D and oil pL obtained as a result of chemical analysis NJ This 1st well with the required frequency and recorded in the EPROM of the block, the Svn and G value is calculated. For the purpose of use, the result is transmitted to the higher stage and registered there in the registration block 20. After transferring the results of the calculation to the upper stage by a single signal from block 7, IM 8 is opened and the separator starts emptying. The moment of the complete reset of the low-voltage device to the collector 6 is determined by the zero signal obtained from the output of the differential pressure gauge 2 f. As soon as in block 7 from the differential pressure gauge 21 a zero signal appears, immediately following the program, the next well in turn (not shown) is connected to this measurement system.

Claims (2)

1. Method for automatic measurement of oil flow rate, including measuring the pressure of a piezometric liquid column in a separator and determining the weight flow rate of an oil liquid, which is so that, in order to improve measurement accuracy and enhance functionality due to the possibility of measuring formation water, differential pressure between two points located in the lower part of the separator, and from the measured differential the moment of separator emptying is measured, the differential pressure is measured, creating Perform at the same height and piezometric columns of oil liquid and antifreeze placed in a special container, and the flow rate of oil and produced water is determined by the formulas (l-d.) AR ) PS-PH ( where / En / ъ - respectively, the density of oil and produced water; 0a - the water content in the produced petroleum fluid; Vh is the volume of the separator to the level h; g is the time of filling the separator to the level h; 5 GH, GB-, respectively, daily weight flow rate of oil and produced water. 2. An apparatus for automatically measuring the oil flow rate, comprising a separator, a piezometric pressure sensor, 0 actuators mounted on the filling and discharge lines, and control and recording units, characterized in that, in order to improve measurement accuracy and extend the functional 5 possibilities due to the possibility of measuring the produced water, a special water tank was additionally introduced, the upper part of which is connected to the gas line of the separator, piezometric pressure sensors installed in the lower part of the separator and the special tank, two differential pressure gauges whose inputs are connected through separating vessels to the sensors. 3 outputs - to the inputs of the control unit, a signal separator of the oil liquid level in the separator, connected to the input of the control unit, the outputs of which are connected to the recording unit and the actuators.