Intelligent water cutting system of liquefied hydrocarbon spherical tank and water cutting method of intelligent water cutting system

Abstract

The invention belongs to the technical field of automatic water cutting systems of storage tanks, and particularly relates to an intelligent water cutting system of a liquefied hydrocarbon spherical tank, which comprises a spherical tank, a tank root valve, a desilting pipe and a water cutting tank, an inlet valve is arranged on a connecting pipeline of the desilting pipe and the water cutting tank, a water cutting pipeline is arranged at a bottom water outlet of the water cutting tank, and a floating ball valve device is arranged at a bottom inner water outlet of the water cutting tank. The water cutting pipeline is provided with a water cutting valve, the top of the water cutting tank is provided with a level gauge extending into the water cutting tank, a pressure balance pipeline is arranged between an opening of the side wall of the water cutting tank and the water cutting pipeline, and the pressure balance pipeline is provided with a balance valve; the water draining device further comprises a water draining controller and a plurality of externally-attached liquid level switches installed on the outer side wall of the water draining tank. According to the intelligent water cutting system, the interface level meter is calibrated in real time through the externally-attached liquid level switch, water in the water cutting tank can be drained safely, conveniently and rapidly, the situation that the floating ball blocks the water outlet under high pressure is avoided, the situation that normal water cutting work is affected due to failure or damage of the interface level meter is avoided, the water drainage efficiency is high, and the water drainage effect is good.

Description

Technical Field

[0001] The invention belongs to the technical field of automatic water cutting of a liquefied hydrocarbon spherical tank, and in particular relates to an intelligent water cutting system and a water cutting method of a liquefied hydrocarbon spherical tank. Background Art

[0002] In the prior art, liquefied hydrocarbons are generally stored or transported in spherical tanks that can withstand high pressure. Due to the presence of water in the liquefied hydrocarbons stored in the spherical tanks, in places where liquefied hydrocarbons are used, most of the liquefied hydrocarbons with higher purity are required to meet the use needs. At the same time, the water deposited at the bottom of the spherical tank for long-term storage of liquefied hydrocarbons will also occupy the internal space of the spherical tank, affecting the storage space of the liquefied hydrocarbons in the spherical tank. In addition, the accumulated water is also likely to cause rust on the inner wall of the spherical tank, which will also affect the service life of the spherical tank and the quality of the liquefied hydrocarbons. It is necessary to cut off the water in the spherical tank in time.

[0003] To this end, some people have also developed a water cutting tank connected to the bottom of the spherical tank for water cutting work, which can remove the accumulated water at the bottom of the spherical tank to obtain liquefied hydrocarbons with higher purity, so as to reduce the space occupied by the accumulated water and avoid the corrosion of the inner wall of the spherical tank by the accumulated water. The liquid level in the tank is detected by a liquid level detector installed on the water cutter that can continuously detect the inside of the water cutting tank. When the liquid level reaches the height required to cut water, the water cutter is started to cut water. However, the liquid level detector is easy to be damaged or fail after long-term use, which makes it easy for accidental water cutting to occur, greatly affecting the safe use of the water cutter.

[0004] Therefore, it is urgent to develop an intelligent water cutting system and water cutting method for liquefied hydrocarbon spherical tanks that are convenient and fast to drain, have high drainage efficiency, and are safe and reliable. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art, and specifically discloses a water cut-off system for a liquefied hydrocarbon spherical tank. The water cut-off system calibrates the level gauge in real time through an external liquid level switch to ensure accurate detection, and can more conveniently and quickly discharge the water in the water cut-off tank in a timely manner to avoid the float ball clogging the water outlet under high pressure, with high drainage efficiency and good drainage effect.

[0006] In order to achieve the above technical objectives, the present invention is implemented according to the following technical solutions:

[0007] The intelligent water cut-off system for a liquefied hydrocarbon spherical tank of the present invention comprises a spherical tank, a tank root valve, a sand settling pipe and a water cut-off tank are sequentially connected at the bottom of the spherical tank through pipelines, the end of the tank root valve penetrates into the sand settling pipe through a downpipe, an inlet valve is arranged on the connecting pipeline of the sand settling pipe and the water cut-off tank, a water cut-off pipeline is arranged at the water outlet at the bottom of the water cut-off tank, a floating ball valve device is arranged at the water outlet at the bottom of the water cut-off tank, a water cut-off valve is installed on the water cut-off pipeline, a contact level gauge extending into the water cut-off tank and capable of continuously detecting the hydrocarbon / water interface is arranged on the top of the water cut-off tank, a pressure balance pipeline is arranged between the side wall opening of the water cut-off tank and the water cut-off pipeline, and a balance valve is installed on the pressure balance pipeline;

[0008] It also includes a water cut controller: the water cut controller is connected to the inlet valve, the interface level meter, the water cut valve, and the balancing valve through electrical signals, and controls the start and close of the inlet valve, the water cut valve, and the balancing valve in real time according to the reading of the interface height position of the interface between the liquefied hydrocarbon and water read by the interface level meter;

[0009] It also includes a plurality of external liquid level switches which are installed on the outer side wall of the water cutting tank from top to bottom and are used to calibrate the boundary level meter.

[0010] As a further improvement of the above technology, the external liquid level switch is a non-contact ultrasonic liquid level sensor.

[0011] In the present invention, the external liquid level switch can be installed in the following ways:

[0012] First, there are three external liquid level switches, which are respectively located at the upper, middle and lower height positions of the side wall of the water cutting tank.

[0013] Second, there are two external liquid level switches, which are respectively located at two different height positions, upper and lower, of the side wall of the water cutting tank.

[0014] Third, there is one external liquid level switch, which is located at the middle height of the side wall of the water cutting tank.

[0015] As a further improvement of the above technology, the float valve device includes a float valve body, a float, and a limit assembly. The outlet end of the float valve body is connected to the water cut pipeline. The float valve body and the limit assembly are both installed at the bottom of the water cut tank. The float is placed in the area surrounded by the float valve body and the limit assembly. The density of the float is between the density of water and the density of liquefied hydrocarbons.

[0016] The present invention also discloses a water cutting method of the intelligent water cutting system of the liquefied hydrocarbon spherical tank, and the specific steps are:

[0017] (1) First, the interface height position H0 of the liquefied hydrocarbon and water interface in the water cut tank where water cut is to be initiated is set in the water cut controller;

[0018] (2) Then, the interface height position of the interface between the liquefied hydrocarbon and the water in the cut-off tank is measured by the interface level meter. When the position reaches H0, the cut-off controller receives the detected interface height data, and sends a signal to close the cut-off valve and the inlet valve, start the balancing valve, and conduct the pressure balancing pipeline. The pressure above and below the float valve device in the cut-off tank reaches equilibrium, the float floats up, and then the balancing valve is closed, and the cut-off valve is opened to conduct the cut-off pipeline for drainage;

[0019] (3) Then, when the water level drops to a low level, the float automatically blocks the outlet of the float valve body after it falls, closing the water cut-off valve to stop drainage;

[0020] (4) Finally, when the interface meter fails due to long-term use or malfunctions and cannot accurately detect the height position of the interface between liquefied hydrocarbon and water in the cut-off tank, the three external liquid level switches will calibrate the accuracy of the measurement value of the interface meter to determine whether the interface meter can be used normally. If the calibration result shows that the measurement value of the interface meter is inaccurate, the control system will automatically close the cut-off valve and sound an alarm, waiting for the fault to be resolved.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The intelligent water cut-off system of the liquefied hydrocarbon spherical tank of the present invention comprises a water cut-off controller, a water cut-off valve, a plurality of water level gauges, an inlet valve and a balancing valve. When the water level of the interface in the water cut-off tank measured by the water level gauge reaches the point where drainage is required, the water cut-off controller opens the balancing valve and conducts the pressure balancing pipeline to make the float float up. The water cut-off valve is opened, and the water cut-off pipeline of the water cut-off tank is effectively drained, thereby avoiding the situation that the float blocks the drain port when the pressure difference between the upper and lower parts of the water cut-off tank is large. The problem of pressure difference between the upper and lower parts of the float valve device inside the water cut-off tank can be solved in a timely and effective manner, thereby ensuring smooth drainage of the water cut-off tank.

[0023] (2) The intelligent water cut-off system for the liquefied hydrocarbon spherical tank of the present invention is provided with a continuous liquid level meter capable of continuously measuring the liquid level inside the water cut-off tank, and a plurality of external liquid level switches installed at different heights on the side wall of the water cut-off tank for real-time calibration of the detection value of the continuous liquid level meter, thereby ensuring the accuracy of the detection interface height of the continuous liquid level meter, effectively preventing the occurrence of inaccurate detection events of the continuous liquid level meter after long-term use, improving the accuracy of water level detection, ensuring the smooth operation of the water cut-off system, and improving the water cut-off efficiency;

[0024] (3) The water cut-off system of the liquefied hydrocarbon spherical tank described in the present invention controls the opening and closing of each valve through a water cut-off controller to achieve accurate and timely water cut-off and drainage work, has a high degree of automation, and is easy to promote and apply. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments:

[0026] Figure 1 It is a structural schematic diagram of the intelligent water cutting system of the liquefied hydrocarbon spherical tank of the present invention (undrained state);

[0027] Figure 2 It is a structural schematic diagram of the intelligent water cutting system of the liquefied hydrocarbon spherical tank described in the present invention (drainage state). DETAILED DESCRIPTION

[0028] like Figure 1 , Figure 2 As shown, the intelligent water cut-off system of a liquefied hydrocarbon spherical tank 1 of the present invention comprises a spherical tank 1, at the bottom of which a tank root valve 2, a sand settling pipe 3 and a water cut-off tank 4 are sequentially connected through pipelines, the end of the tank root valve 2 penetrates into the sand settling pipe 3 through a downpipe 5, an inlet valve 6 is arranged on the connecting pipeline of the sand settling pipe 3 and the water cut-off tank 4, a water cut-off pipeline 10 is arranged at the water outlet at the bottom of the water cut-off tank 4, a float valve device 7 is arranged at the water outlet at the bottom of the water cut-off tank 4, a water cut-off valve 8 is installed on the water cut-off pipeline 10, a contact level gauge 9 which can continuously measure the hydrocarbon / water interface and extends into the water cut-off tank 4 is arranged on the top of the water cut-off tank 4, a pressure balance pipeline 20 is arranged between the side wall of the water cut-off tank 4 and the water cut-off pipeline 10, and a balance valve 11 is installed on the pressure balance pipeline 20;

[0029] The water cut controller 30 is also included: the water cut controller 30 is connected to the inlet valve 6, the interface level meter 9, the water cut valve 8, and the balancing valve 11 through electrical signals, and controls the start and close of the inlet valve 6, the water cut valve 8, and the balancing valve 11 in real time according to the reading of the interface height position of the interface between the liquefied hydrocarbon and the water read by the interface level meter 9;

[0030] It also includes a plurality of external liquid level switches 12 installed on the outer side wall of the water cutting tank 4 from top to bottom for calibrating the boundary level meter 9.

[0031] In the present invention, the external liquid level switch 12 is a non-contact ultrasonic liquid level sensor, and there are three external liquid level switches 12, which are respectively located at the upper, middle and lower height positions of the side wall of the water cut tank 4. In addition, there can be two external liquid level switches, which are respectively located at the upper and lower height positions of the side wall of the water cut tank; there can also be one external liquid level switch, which is located at the middle height position of the side wall of the water cut tank. Users can install it according to actual needs on site.

[0032] The float valve device 7 includes a float valve body 71, a float 72, and a limit assembly 73. The outlet end of the float valve body 71 is connected to the water cut pipeline 10. The float valve body 71 and the limit assembly 73 are both installed at the bottom position of the water cut tank 4. The float 72 is placed in the area surrounded by the float valve body 71 and the limit assembly 73. The density of the float 72 is between the density of water and the density of liquefied hydrocarbons.

[0033] The present invention also discloses a water cutting method of the intelligent water cutting system of the liquefied hydrocarbon spherical tank 1, and the specific steps are:

[0034] (1) First, the interface height position H0 of the interface between the liquefied hydrocarbon and the water in the water cut tank 4 where water cut is to be initiated is set in the water cut controller 30;

[0035] (2) Next, the interface height position of the interface between the liquefied hydrocarbon and the water in the cut-off tank 4 is measured by the interface level meter 9. When the position reaches H0, the cut-off controller 30 receives the detected interface height data, and sends a signal to close the cut-off valve 8 and the inlet valve 6, start the balancing valve 11, and conduct the pressure balancing pipeline 20. The upper and lower pressures of the float valve device 7 in the cut-off tank 4 are balanced, and the float 72 floats up. Then the balancing valve 11 is closed, and the cut-off valve 8 is opened to conduct the cut-off pipeline 10 for drainage.

[0036] (3) Then, when the water level drops to a low level, the float 72 automatically blocks the water outlet of the float valve body 71 after falling, and closes the water cut-off valve 8 to stop drainage;

[0037] (4) Finally, when the interface meter 9 fails due to long-term use or malfunctions and is unable to accurately detect the height position of the interface between the liquefied hydrocarbon and the water in the water cut-off tank 4, the three external liquid level switches 12 will calibrate the accuracy of the measurement value of the interface meter 9, thereby calibrating whether the interface meter 9 can be used normally. When the calibration result shows that the measurement value of the interface meter 9 is inaccurate, the control system will automatically close the water cut-off valve 8 and sound an alarm, waiting for the fault to be resolved.

[0038] The present invention is not limited to the above-mentioned embodiments. Any changes or modifications to the present invention do not depart from the spirit and scope of the present invention. If these changes and modifications fall within the scope of the claims and equivalent technologies of the present invention, the present invention is also meant to include these changes and modifications.

Claims

1. An intelligent water cutting system for a liquefied hydrocarbon spherical tank, comprising a spherical tank, characterized in that: The bottom of the spherical tank is connected in sequence with a tank root valve, a sand settling pipe, and a water cut-off tank through pipelines. The end of the tank root valve penetrates into the sand settling pipe through a downpipe. An inlet valve is provided on the connecting pipeline of the sand settling pipe and the water cut-off tank. A water cut-off pipeline is provided at the water outlet at the bottom of the water cut-off tank. A floating ball valve device is provided at the water outlet at the bottom of the water cut-off tank. A water cut-off valve is installed on the water cut-off pipeline. A contact level gauge that extends into the water cut-off tank and can continuously detect the hydrocarbon / water interface is provided on the top of the water cut-off tank. A pressure balance pipeline is provided between the side wall opening of the water cut-off tank and the water cut-off pipeline. A balance valve is installed on the pressure balance pipeline. It also includes a water cut controller: the water cut controller is connected to the inlet valve, the interface level meter, the water cut valve, and the balancing valve through electrical signals, and controls the start and close of the inlet valve, the water cut valve, and the balancing valve in real time according to the reading of the interface height position of the interface between the liquefied hydrocarbon and water read by the interface level meter; It also includes a plurality of external liquid level switches which are installed on the outer side wall of the water cutting tank from top to bottom and are used to calibrate the boundary level meter.

2. The intelligent water cutting system for liquefied hydrocarbon spherical tank according to claim 1 is characterized in that: The external liquid level switch is a non-contact ultrasonic liquid level sensor.

3. The intelligent water cutting system for liquefied hydrocarbon spherical tank according to claim 2 is characterized in that: There are three external liquid level switches, which are respectively located at three different height positions of the upper, middle and lower side walls of the water cutting tank.

4. The intelligent water cutting system for liquefied hydrocarbon spherical tank according to claim 2 is characterized in that: There are two external liquid level switches, which are respectively located at two different height positions, upper and lower, of the side wall of the water cutting tank.

5. The intelligent water cutting system for liquefied hydrocarbon spherical tank according to claim 2 is characterized in that: There is one external liquid level switch, which is located at a height position in the middle of the side wall of the water cutting tank.

6. The intelligent water cutting system for liquefied hydrocarbon spherical tank according to claim 1 is characterized in that: The float valve device includes a float valve body, a float, and a limit assembly. The outlet end of the float valve body is connected to the water cut pipeline. The float valve body and the limit assembly are both installed at the bottom position in the water cut tank. The float is placed in the area surrounded by the float valve body and the limit assembly. The density of the float is between the density of water and the density of liquefied hydrocarbons.

7. The water cutting method of the intelligent water cutting system of the liquefied hydrocarbon spherical tank according to any one of claims 1 to 6, wherein the specific steps are: (1) First, the interface height position H0 of the liquefied hydrocarbon and water interface in the water cut tank where water cut is to be initiated is set in the water cut controller; (2) Then, the interface height position of the interface between the liquefied hydrocarbon and the water in the cut-off tank is measured by the interface level meter. When the position reaches H0, the cut-off controller receives the detected interface height data, and sends a signal to close the inlet valve, start the balancing valve, and conduct the pressure balancing pipeline. The pressure above and below the float valve device in the cut-off tank reaches equilibrium, the float floats up, and then the balancing valve is closed, and the cut-off valve is opened to conduct the cut-off pipeline for drainage; (3) Then, when the water level drops to a low level, the float automatically blocks the outlet of the float valve body after it falls, closing the water cut-off valve to stop drainage; (4) Finally, when the interface meter fails due to long-term use or malfunctions and is unable to accurately detect the height position of the interface between liquefied hydrocarbons and water in the cut-off tank, the external liquid level switch will calibrate the accuracy of the measurement value of the interface meter to determine whether the interface meter can be used normally. If the calibration result shows that the measurement value of the interface meter is inaccurate, the control system will automatically close the cut-off valve and sound an alarm, waiting for the fault to be resolved.

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