SU754368A1 - Device for injection of inhibitor into gas flow - Google Patents

Description

The invention relates to the automation of gas production facilities, in particular to the regulation of the consumption of a hydrate formation inhibitor introduced into the gas stream.

A device is known that contains an inhibitor flow sensor and an actuator, as well as gas flow and temperature sensors, which, using regulators, work out the inhibitor consumption [ί] proportional to these parameters.

In this device, the required amount of inhibitor, the task of which is introduced into the regulator, is determined by calculation. The calculations are approximate and do not take into account the influence of a number of factors, so the device does not provide the required accuracy.

The closest technical solution to the invention is a device containing a control valve with a position sensor and a gas flow sensor installed on the gas supply pipeline, the first reference element, the first chamber of which is connected to the flow sensor directly, and the second through the first valve, and the first and second keys associated with the stem of the first element of comparison

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and with the inlet of the first valve and the inlet of the second valve installed in the pipeline of the inhibitor supply. The disadvantage of this device is low accuracy, as a result of which the inhibitor is not productively consumed.

In gas fields, where the wells are involved in the automatic flow rate control system, gas consumption may change several times a day. At the same time, any change in the flow rate leads to unproductive input of the inhibitor during the device settings.

The aim of the invention is to improve the accuracy of the device.

This goal is achieved by the fact that the device contains the third valve, the second comparison element and the third and fourth keys connected to the stem of the second comparison element, the first chamber of which is connected to the 25 position sensor directly, and the second through the third valve, the third key is connected to the entrance of the second valve, and the fourth key - with the entrance of the first and the entrance of the third valve.

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It is a schematic diagram of the device.

The device contains a control valve 1 with a position sensor 2 and a gas flow sensor 3 installed on the gas supply pipe 4, the first 5 and second 6 reference elements, separated respectively by sensitive elements 7 and 8 with rigid centers 9 and 10 into chambers 11, 12 and 13,

14. The first chamber 11 of the first reference element 5 is connected to the output of the flow sensor 3 directly by pulse tube 15, and the second chamber 12 via the first fan 16.

The hard center 9 of the first comparison element 5 is connected to a rod 17, to which the first 18 and second 19 keys are connected, connected with the control input 20 of the first valve 16 and with the control 21 input of the second valve 22 installed in the inhibitor supply line 23.

The first chamber 13 of the reference element 6 is connected to the output of the position sensor 2 of the control valve 1 directly, and the second chamber 14 through the third valve 24.

With the hard center 10 of the second element of comparison b the rod 25 is connected, to which the third key is connected

26, connected to the control input 21 of the second valve 22, and the fourth key

27 connected to the control input 20 of the first valve 16 and the control input 28 of the third valve 24.

The device works as follows.

In the normal process mode, when the gas flow through the pipeline 4 is as specified, the output signal of the gas flow sensor 3 enters both chambers 11 and 12 of the first comparison element 5, and the first chamber 11 is pulsed directly through the pulse chamber 15, and the second through 12 the first valve 16 is opened forcibly with a short pulse. In this case, the sensitive element 7 of the first element of comparison 5 is in equilibrium, and the first 18 and second 19 keys are open, and the inhibitor does not enter the pipeline through the line 21 through the second valve 22 waters 4.

In the case of the formation of hydrates in the pipeline 4, the gas flow rate decreases, and, consequently, the output value of the gas flow sensor 3. The pressure in the first chamber 11 of the first reference element 5 decreases, which leads to imbalance of the sensitive element 7, which sags , · Moves the hard center 9 and the rod 17 - and closes the first key 18.

Since during hydrate formation the position of the control valve 1 and, accordingly, the size of the output _

The signal of position sensor 2 has not changed, then the position of the output rod 25 of the second element of comparison 6 remains unchanged, i.e. the third key 26 remains closed. When the first key 18 is closed, the signal goes to the control 21 input of the second valve 22 and the inhibitor enters pipeline 4 through line 23, hydrates collapse, which leads to an increase in the output signal of the gas flow sensor 3 and restoring the balance of the sensitive element 7 of the first comparison element 5. Output the rod 17, moving to the left, opens the first key 18, which turns off the signal to the control input 21 of the second valve 22. The supply of the inhibitor is stopped.

If a decrease in gas flow occurs as a result of a change in the position of the control valve 1, this causes a decrease in the output signal of the position sensor 2, as a result of which the pressure in the first chamber 13 of the second comparison element 6 decreases and the output rod 25, moving to the left, opens the third key 26, which prevents the signal from the control input 21 of the second valve 22, while simultaneously closing the first switch 18, associated with a decrease in the output signal of the gas flow sensor 3.

As a result, the second valve 22 remains closed and the inhibitor c. pipeline 4 is not supplied.

Moving the rod -25 to the left also leads to the closure of the fourth key 27. In this case, the signal goes to the control inputs 20 and 28 of the first

16 and third 24 valves that open. Pressure is leveled in chambers 11 and 12 of the first element of comparison 5 and chambers 13 and 14 of the second element of comparison 6. First 18

and the fourth 27 keys is opened, the third key 26 is closed and the device returns to its original position.

With an increase in gas flow rate associated with the regulation of flow rate, the output signal of the sensor ⁴ ka gas flow 3 and position sensor 2 of the control valve 1 increases. Increasing the pressure in the first chamber 11 of the first comparison element 5 causes the output rod to move

17 left, which causes the closure of the second key 19. The signal is fed to the control inputs 20 and

28 respectively the first 16 and third 14 valves that open. The pressure is leveled in the first 11 and second 12 chambers of the first element of comparison 5 and chambers 13 and 14 of the second element of comparison 6, and the output rod 17 returns to test

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(working position, opening the second \ key 19.

Thus, the proposed device improves the accuracy of the injection of the inhibitor into the gas stream in cases of reduced consumption associated with hydrate formation. As a result, the unproductive consumption of the inhibitor introduced into the gas pipeline is eliminated.

The magnitude of the annual savings due to a reduction in the consumption of the inhibitor is about 4.tys on average. rubles per year.

Claims (1)

Claim A device for introducing an inhibitor into the gas flow, containing a control valve with a position sensor and a gas flow sensor installed 20 in the gas supply pipeline, the first reference element, the first chamber of which is connected to the flow sensor directly, and the second through the first valve, and the first and second keys connected with the stem of the first comparison element and with the input of the first valve and the input of the second valve installed on the pipeline of the inhibitor supply, characterized in that, in order to improve the accuracy of the device, it contains the third valve, the second the comparison element and the third and fourth keys connected Ιθ with the stem of the second comparison element, the first chamber of which is connected to the position sensor directly, and the second through the third valve, the third key is connected to the input of the second valve, and four th key - with the input of the first and the input A third valves. :