A closed oil unloading device for a crude oil tanker

Abstract

The present invention relates to a closed oil unloading device for a crude oil tank truck, comprising a sealing unit, an oil storage unit, and a transmission unit connected in sequence; the sealing unit comprises a first valve, a filtering device, and a second valve connected in sequence; the oil storage unit comprises an oil storage tank and a heating device arranged in the tank; the oil and gas outlet at the top of the oil storage tank is connected to the transmission pump; the oil outlet at the bottom of the storage tank pipe is connected to the transmission pump; the transmission unit comprises a transmission pump, a third valve, a fourth valve, and a fifth valve connected in sequence; a sixth valve is arranged between the oil and gas outlet at the top of the oil storage tank and the transmission pump; a pressure detector is arranged between the oil and gas outlet and the sixth valve. The oil unloading device provided by the present invention realizes the closed unloading of oil, and at the same time, the oil and oil and gas in the oil tank are transported through different pipelines, avoiding the safety risks and oil and gas leakage when the two are mixed and stored, and also realizes efficient oil unloading, and the oil unloading time is shortened to 1 / 3 of the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of oil unloading equipment, and in particular to a closed oil unloading skid-mounted device for a crude oil tank truck. Background Art

[0002] Oil is one of the important energy sources for industrial and agricultural production. On the one hand, there is an imbalance between oil production and sales locations, and on the other hand, the demand for energy mainly based on oil is increasing, resulting in an upward trend in oil transportation volume.

[0003] For example, CN210825404U discloses a crude oil unloading device, which belongs to the field of petroleum transportation tools, including an oil unloading tank; an inlet pipe arranged at the lower part of the oil unloading tank, on which a valve is arranged; and an outlet pipe arranged at the bottom of the oil unloading tank, which is connected to an oil collecting manifold; wherein a detachable sealing cover is arranged on the oil unloading tank; when the oil enters the oil drain tank from the inlet pipe and flows into the oil collecting manifold through the outlet pipe, the oil drain tank is sealed by the sealing cover. It can avoid harm to personnel caused by toxic and harmful gases such as hydrogen sulfide and benzene in the crude oil due to volatilization and overflow of crude oil during the oil unloading process, and avoid environmental pollution.

[0004] CN205653156U discloses an oil supply and unloading device used in electric power and petrochemical systems, including an oil inlet pipe and an oil storage tank connected by a pipeline, a first stop valve, two parallel power valve groups and a second stop valve are sequentially arranged on the pipeline between the oil inlet pipe and the oil storage tank, and an oil unloading pipeline is also included, one end of the oil unloading pipeline is connected to the pipeline between the first stop valve and the power valve group, and the other end is connected to the pipeline between the second stop valve and the oil storage tank, and a third stop valve is arranged on the oil unloading pipeline. The oil unloading and oil supply devices are combined, and the oil unloading and oil supply devices share a common oil pump, filter screen and inlet and outlet valves, which saves investment in the oil supply pump and related filter screens and valves, and simplifies the system process. The number of connecting ports between the valve and the pipeline is reduced, which can improve the overall stability.

[0005] At present, the way of unloading oil when oil tankers transport crude oil to the station is open unloading. Since crude oil is a mixture of oil, gas and water, VOCs gas will volatilize during the unloading process, which will pollute the environment. It is also flammable and explosive, which brings many safety hazards to the unloading of crude oil. Therefore, how to improve the unloading efficiency and avoid safety hazards while reducing environmental pollution has become an urgent matter. Although the prior art discloses the use of a closed system to realize the unloading and loading of crude oil, there are still oil and gas pipelines and oil storage tanks connected during the unloading and loading process, resulting in extremely poor system tightness, which is easy to cause oil and gas leakage, and there is a great safety risk. Summary of the invention

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a closed oil unloading device for a crude oil tanker, which can realize the separate transmission of oil gas and oil during the unloading process or in the later stage of unloading, avoid the safety risks and leakage of oil gas when the two are mixed and stored, and also realize efficient unloading, and the unloading time is shortened to at least 1 / 3 of the original.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] The present invention provides a closed oil unloading device for a crude oil tank truck, the closed oil unloading device for a crude oil tank truck comprises a sealing unit, an oil storage unit, and a transmission unit connected in sequence;

[0009] The sealing unit comprises a first valve, a filtering device and a second valve connected in sequence;

[0010] The oil storage unit comprises an oil storage tank and a heating device arranged in the tank;

[0011] The transmission unit includes a transmission pump, a third valve, a fourth valve and a fifth valve connected in sequence;

[0012] The oil storage tank is provided with a liquid level gauge;

[0013] The oil and gas outlet at the top of the oil storage tank is connected to the transmission pump;

[0014] The oil outlet at the bottom of the tank pipe is connected to the delivery pump;

[0015] A sixth valve is provided between the oil and gas outlet at the top of the oil storage tank and the transmission pump; a pressure detector is provided between the oil and gas outlet and the sixth valve;

[0016] A pressure detection device is provided between the transmission pump and the third valve;

[0017] A moisture analysis device and a temperature detection device are arranged between the fourth valve and the fifth valve.

[0018] The oil unloading device provided by the present invention realizes the closed unloading of oil through the overall design of the device, and at the same time transports the oil and oil gas in the oil tank through different pipelines, avoiding the safety risks and oil and gas leakage caused by the mixed storage of the two, and also realizes efficient oil unloading, and the oil unloading time is shortened to 1 / 3 of the prior art.

[0019] In the present invention, the oil storage tank can be other oil storage equipment, that is, not limited to tank-shaped oil storage equipment, and can be other equipment that can store oil. The opening position and size of the oil inlet in the oil storage tank, as well as the length, shape, and opening direction after being introduced into the oil storage equipment can be selected according to the existing feeding method of oil into the oil storage equipment. For example, heavy oil can be fed from the top, and light oil can be fed from the bottom.

[0020] In the present invention, safety valves and pressure relief valves are arranged at the inlet and outlet of the transmission pump to ensure the safety of operation.

[0021] As a preferred technical solution of the present invention, the first valve includes a breakaway valve or a ball valve.

[0022] Preferably, the filtering device comprises a basket filter.

[0023] Preferably, the second valve comprises an electric switching valve.

[0024] Preferably, the second valve is connected to a PLC controller.

[0025] As a preferred technical solution of the present invention, the oil storage tank is provided with an oil inlet.

[0026] Preferably, the oil inlet is connected to the second valve.

[0027] Preferably, as a preferred technical solution of the present invention, the pressure detector is connected to a PLC controller.

[0028] Preferably, the sixth valve comprises an electric switching valve.

[0029] Preferably, a seventh valve is provided between the oil outlet at the bottom of the tank pipe and the transfer pump.

[0030] Preferably, the seventh valve comprises a shut-off valve.

[0031] As a preferred technical solution of the present invention, the liquid level meter is connected to a PLC controller.

[0032] As a preferred technical solution of the present invention, the heating device includes a heating pipe.

[0033] Preferably, the heating pipe is provided with an eighth valve and a ninth valve.

[0034] Preferably, the eighth valve and the ninth valve are both manual ball valves.

[0035] As a preferred technical solution of the present invention, a sewage outlet is provided at the bottom of the oil storage tank.

[0036] Preferably, the sewage outlet is provided with a manual ball valve.

[0037] As a preferred technical solution of the present invention, the transfer pump includes a screw gas-liquid mixed transfer pump.

[0038] Preferably, the pressure detection device comprises a pressure gauge.

[0039] Preferably, the third valve comprises a check valve.

[0040] As a preferred technical solution of the present invention, the moisture analysis device includes a moisture analyzer.

[0041] Preferably, the temperature detection device comprises a temperature meter.

[0042] Preferably, the moisture analysis device and the temperature detection device are respectively connected to a PLC controller.

[0043] As a preferred technical solution of the present invention, the fourth valve includes a stop valve.

[0044] Preferably, the fifth valve comprises an electric valve.

[0045] Preferably, the fifth valve is connected to a PLC controller.

[0046] Compared with the prior art solutions, the present invention has at least the following beneficial effects:

[0047] (1) Fully enclosed unloading, which can be shut off in an emergency. Oil and gas are transmitted separately during the transmission process, which has the advantages of safety and environmental protection. Water content, temperature and pressure are monitored online, and the oil pump is frequency-controlled with a high degree of automation.

[0048] (2) It can accept multiple tank trucks unloading at the same time, with high unloading efficiency, and can realize the heavy oil unloading process without zero-position tank, streamline the process to reduce oil loss and avoid repeated heating. On the basis of improved safety, environmental protection and energy saving, the unloading time is shortened to 1 / 3 of the existing technology. It can be designed as an independent skid, which is convenient and quick to install. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 The invention discloses a closed oil unloading device for a crude oil tanker provided by an embodiment of the present invention.

[0050] In the figure: 1-first valve, 2-filtering device, 3-second valve, 4-oil storage tank, 4.1-heating device, 4.1.1-eighth valve, 4.1.2-ninth valve, 5-seventh valve, 6-manual ball valve, 7-liquid level gauge, 8-sixth valve, 9-transmission pump, 10-pressure detection device, 11-third valve, 12-moisture analysis device, 13-temperature detection device, 14-fourth valve, 15-fifth valve, 16-pressure detection instrument.

[0051] The present invention is further described in detail below. However, the following examples are only simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims. DETAILED DESCRIPTION

[0052] To better illustrate the present invention and facilitate understanding of the technical solution of the present invention, typical but non-limiting embodiments of the present invention are as follows:

[0053] Example

[0054] This embodiment provides a closed oil unloading device for a crude oil tanker, such as Figure 1 As shown, the closed oil unloading device of the crude oil tanker includes a sealing unit, an oil storage unit, and a transmission unit connected in sequence;

[0055] The sealing unit comprises a first valve 1, a filtering device 2 and a second valve 3 connected in sequence;

[0056] The first valve 1 may be a breakaway valve or a ball valve;

[0057] The filtering device is a basket filter;

[0058] The second valve 3 comprises an electric switch valve;

[0059] The second valve 3 is connected to a PLC controller.

[0060] The oil storage unit comprises an oil storage tank 4 and a heating device 4.1 arranged in the tank;

[0061] The oil storage tank 4 is provided with an oil inlet; the oil inlet is connected to the second valve 3 .

[0062] The oil and gas outlet at the top of the oil storage tank 4 is connected to the transfer pump 9;

[0063] The oil outlet at the bottom of the tank pipe is connected to the delivery pump 9;

[0064] A sixth valve 8 is provided between the oil and gas outlet at the top of the oil storage tank 4 and the transfer pump 9;

[0065] A pressure detector 16 is provided between the oil and gas outlet and the sixth valve 8;

[0066] The pressure detector 16 is connected to the PLC controller;

[0067] The sixth valve 8 is an electric control valve;

[0068] A seventh valve 5 is provided between the oil outlet at the bottom of the tank pipe and the delivery pump 9;

[0069] The seventh valve 5 is a stop valve.

[0070] The oil storage tank 4 is provided with a liquid level gauge 7;

[0071] The liquid level meter 7 is connected to the PLC controller.

[0072] The bottom of the oil storage tank 4 is provided with a sewage outlet;

[0073] The sewage outlet is provided with a manual ball valve 6.

[0074] The heating device 4.1 comprises a heating pipe;

[0075] The outlet and inlet of the heat tracing pipe are respectively provided with an eighth valve 4.1.1 and a ninth valve 4.1.2;

[0076] The eighth valve 4.1.1 and the ninth valve 4.1.2 are both manual ball valves.

[0077] The transmission unit includes a transmission pump 9, a third valve 11, a fourth valve 14 and a fifth valve 15 connected in sequence. The transmission pump 9 includes a screw gas-liquid mixed transmission pump 9;

[0078] A pressure detection device 10 is provided between the transmission pump 9 and the third valve 11;

[0079] The pressure detection device 10 includes a pressure gauge;

[0080] The third valve 11 includes a check valve.

[0081] A moisture analysis device 12 and a temperature detection device 13 are provided between the fourth valve 14 and the fifth valve 15; the moisture analysis device 12 comprises a moisture analyzer;

[0082] The temperature detection device 13 includes a temperature meter;

[0083] The moisture analysis device 12 and the temperature detection device 13 are connected to the PLC controller respectively.

[0084] The fourth valve 14 is a stop valve;

[0085] The fifth valve 15 is an electric valve;

[0086] The fifth valve 15 is connected to a PLC controller.

[0087] Application Examples

[0088] This application example uses the closed oil unloading device for crude oil tank trucks provided in the above embodiment to unload oil, and the specific process is as follows:

[0089] The input port of the first valve 1 is connected to the oil unloading hose of the oil unloading tank truck as the crude oil inlet, and is manually opened when unloading and closed when not unloading. The output port of the first valve 1 is connected to the input port of the second valve 3 through the filter device 2. The filter device 2 is a basket filter in this application example, which is used to filter solid particles and impurities in the crude oil. The second valve 3 is electrically connected to the PLC and can be remotely closed by the PLC in the second emergency. The output port of the second valve is connected to the input port of the oil storage tank 4 through a pipeline. The crude oil input by the oil unloading tank truck passes through the first valve 1, the filter device 2 and the second valve 3 in sequence and enters the oil storage tank 4.

[0090] The oil storage tank 4 in this application example is a Φ1200×2000 horizontal storage tank for temporary storage of crude oil. A heating device 4.1 is provided inside the oil storage tank 4. The heating device 4.1 is a heat tracing pipe used to heat the crude oil in the oil storage tank 4 under low temperature conditions. The inlet and outlet of the heat tracing pipe are respectively provided with a ninth valve 4.1.2 and an eighth valve 4.1.2, both of which are manual ball valves and are respectively provided at the bottom of the shell of the oil storage tank 4. A drain valve is provided at the bottom of the shell of the oil storage tank 4. The drain valve is a manual ball valve 6. The drain valve is connected to the drain pipe and is used to discharge impurities in the oil storage tank 4. A liquid level gauge 7 is provided at one end of the shell of the oil storage tank 4. The two ends of the liquid level gauge 7 are respectively connected to the oil storage tank 4 through flanges. The liquid level gauge 7 is connected to the PLC and is used to monitor the height of the crude oil level in the oil storage tank 4 and send the liquid level height information to the PLC. The output port of the oil storage tank 4 is arranged at the bottom of the tank body, and the output port of the oil storage tank 4 is connected to the input port of the seventh valve. The seventh valve 5 serves as the crude oil output port of the oil storage tank 4 and is in a normally open state.

[0091] The oil and gas output port of the oil storage tank 4 is arranged at the top of the tank body, and the oil and gas output port of the oil storage tank 4 is connected to the input port of the sixth valve 8 through a pipeline. The sixth valve 8 is in a normally open state and is an electric control valve used to control the discharge of volatile gases in the tank body. A pressure detector 16 is arranged between the oil and gas outlet and the sixth valve 8; the pressure detector 16 is connected to the PLC controller; the output port of the sixth valve 8 and the output port of the seventh valve 5 are connected to the input port of the transmission pump 9 through a pipeline. The transmission pump 9 is a screw gas-liquid mixed transmission pump. The output port of the transmission pump 9 is connected to the input port of the third valve 11 through a pipeline. The third valve 11 is a check valve. The transmission pump 9 is electrically connected to the PLC. The liquid level meter 7 is interlocked with the transmission pump 9 by frequency conversion, which improves the efficiency of crude oil unloading. The third valve 11 is used to prevent crude oil from flowing back. The output port of the third valve 11 is connected to the input port of the fifth valve 15 through the fourth valve 14. The output port of the fifth valve is connected to the three-phase separator. The fourth valve 14 and the fifth valve 15 are in a normally open state. The fifth valve 15 is electrically connected to the PLC and can be remotely closed by the PLC in an emergency. By adding the active oil and gas mixing link, the oil and gas generated during the oil unloading process are pumped to the three-phase separator through the transfer pump 9 together with the original liquid phase, avoiding direct discharge of oil and gas into the atmosphere, reducing environmental pollution, and there is no need to connect the oil and gas pipeline to the oil storage tank, reducing safety risks and truly realizing closed unloading.

[0092] At the same time, a pressure detection device 10 is provided on the pipeline between the transmission pump 9 and the third valve 11, which is a pump outlet pressure gauge, and the pump outlet pressure gauge is used to display the pressure value of the output port of the transmission pump 9 on site; a moisture analysis device 12 and a temperature detection device 13 are provided on the pipeline between the fourth valve 14 and the fifth valve 15 in sequence. The moisture analysis device 12 and the temperature detection device 13 are electrically connected to the PLC respectively. The moisture analysis device 12 is a moisture analyzer used to monitor the water content in the crude oil, and the temperature detection device 13 is a temperature measuring instrument used to measure the temperature value of the crude oil. During the unloading process, the PLC is used for automatic control, data such as water content, temperature, and liquid level are collected, and the transmission pump 9 is frequency-controlled to achieve full-process monitoring of the closed unloading.

[0093] The pressure detector 16 between the oil and gas outlet and the sixth valve 8 and the sixth valve 8 as well as the transmission pump 9 and the liquid level meter 7 are interlocked and controlled by PLC, as follows:

[0094] ① Before each oil unloading operation, adjust the sixth valve 8 to the open state;

[0095] ② After the operation starts, the pressure detector 16 connected to the oil tank 4 will give a high pressure alarm (affecting the gravity oil inlet of the oil tank 4, which can be determined by the interlocking change of the value of the liquid level gauge 7), and the transmission pump 9 will be started at the lowest frequency to reduce the value of the pressure gauge 16 to normal, and the gravity oil inlet of the oil tank 4 will be restored;

[0096] ③ Before the liquid level of the liquid level gauge 7 reaches the high liquid level (interlocking to start the transfer pump liquid level), the pressure detector 16 gives a low pressure alarm (in this application example, the low pressure value is 50% of the saturated vapor pressure of the oil product) and interlocks to stop the transfer pump 9;

[0097] ④ If there is no high pressure or overpressure after the start of step ②, and the gravity oil inlet of the oil storage tank 4 is not affected, the sixth valve 8 is closed and the transfer pump 9 is started normally until the liquid level gauge 7 reaches the high liquid level (interlock start transfer pump liquid level);

[0098] ⑤ If the operation is normal after step ④, the low pressure alarm of the pressure detector 16 must be interlocked to reduce the working frequency of the transmission pump 9, and the ultra-low pressure alarm of the pressure detector 16 (the ultra-low pressure value in this application example is the design negative pressure of the oil storage tank 4 and its accessory system + 0.1MPa) must be interlocked to stop the transmission pump 9;

[0099] ⑥ During the operation, after the interlock stops the transmission pump 9, the interlock is restored and executed from step ②.

[0100] The above interlocking description is executed when the device is operating normally. Other safety, quality and other alarm interlocks are higher than this interlocking. It can prevent the oil storage equipment from being pressurized and causing oil unloading to stagnate. It can prevent the gas-liquid mixture from being transported into the oil storage equipment during the oil unloading process, causing the gas phase material to cause cavitation of the transmission pump, and then causing the oil transportation equipment to be vacuumed to accelerate the volatilization of oil and gas, and even the oil storage equipment and tank trucks to be sucked flat.

[0101] The oil unloading device provided by the present invention realizes the closed unloading of oil through the overall design of the device, and at the same time transports the oil and oil gas in the oil tank through different pipelines, avoiding the safety risks and oil and gas leakage caused by the mixed storage of the two, and also realizes efficient and energy-saving oil unloading, and the oil unloading time is shortened to 1 / 3 of the prior art.

[0102] The applicant declares that the present invention illustrates the detailed structural features of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed structural features, that is, it does not mean that the present invention must rely on the above-mentioned detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the components selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0103] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0104] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0105] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A closed oil unloading device for a crude oil tanker, characterized in that: The closed oil unloading device of the crude oil tank truck comprises a sealing unit, an oil storage unit and a transmission unit connected in sequence; The sealing unit comprises a first valve, a filtering device and a second valve connected in sequence; The oil storage unit comprises an oil storage tank and a heating device arranged in the tank; The transmission unit includes a transmission pump, a third valve, a fourth valve and a fifth valve connected in sequence; The oil storage tank is provided with a liquid level gauge; The oil and gas outlet at the top of the oil storage tank is connected to the transmission pump; The oil outlet at the bottom of the oil storage tank is connected to the delivery pump; A sixth valve is provided between the oil and gas outlet at the top of the oil storage tank and the transmission pump; a pressure detector is provided between the oil and gas outlet and the sixth valve; A pressure detection device is provided between the transmission pump and the third valve; A moisture analysis device and a temperature detection device are provided between the fourth valve and the fifth valve; The moisture analysis device and the temperature detection device are electrically connected to the PLC controller respectively; The pressure detector, the sixth valve, the transmission pump and the liquid level gauge are interlocked and controlled by a PLC controller: ① Before each oil unloading operation begins, adjust the sixth valve to an open state; ② After the operation starts, the pressure detector connected to the oil storage tank will give a high-pressure alarm, and the transmission pump will be started at the lowest frequency of the interlock, so that the value of the pressure detector will decrease to normal, and the gravity oil supply of the oil storage tank will be restored; ③ Before the liquid level of the liquid level gauge reaches the high liquid level, the pressure detector alarms low pressure and interlocks and stops the transmission pump; ④ If there is no high pressure or overpressure after the operation of step ② is started, and the gravity oil supply of the oil storage tank is not affected, the sixth valve is closed until the liquid level gauge reaches the high liquid level, and the transfer pump is started normally at the same time; ⑤ If the operation is normal after step ④, the low pressure alarm of the pressure detector must be interlocked to reduce the working frequency of the transmission pump, and the ultra-low pressure alarm of the pressure detector must be interlocked to stop the transmission pump; ⑥ During the operation, after the interlock stops the transfer pump, the interlock is restored to execute from step ②.

2. The closed oil unloading device for a crude oil tanker according to claim 1, characterized in that: The first valve comprises a breakaway valve or a ball valve; the filtering device comprises a basket filter; the second valve comprises an electric switch valve; and the second valve is connected to a PLC controller.

3. The closed oil unloading device for a crude oil tanker according to claim 1 or 2, characterized in that: The oil storage tank is provided with an oil inlet; the oil inlet is connected to the second valve.

4. The closed oil unloading device for a crude oil tanker as claimed in claim 1, characterized in that: The sixth valve comprises an electric switch valve; a seventh valve is arranged between the oil outlet at the bottom of the oil storage tank and the transmission pump; the seventh valve comprises a stop valve.

5. The closed oil unloading device for a crude oil tanker according to claim 1, characterized in that: The heating device comprises a heating pipe; an eighth valve and a ninth valve are respectively arranged at the outlet and the inlet of the heating pipe; and both the eighth valve and the ninth valve are manual ball valves.

6. The closed oil unloading device for a crude oil tanker according to claim 1 or 5, characterized in that: A sewage outlet is arranged at the bottom of the oil storage tank; and a manual ball valve is arranged at the sewage outlet.

7. The closed oil unloading device for a crude oil tanker as claimed in claim 1, characterized in that: The transmission pump comprises a screw gas-liquid mixed transmission pump; the pressure detection device comprises a pressure gauge; and the third valve comprises a check valve.

8. The closed oil unloading device for a crude oil tanker as claimed in claim 1, characterized in that: The moisture analysis device includes a moisture analyzer; the temperature detection device includes a temperature meter.

9. The closed oil unloading device for a crude oil tanker as claimed in claim 8, characterized in that: The fourth valve comprises a stop valve; the fifth valve comprises an electric valve; and the fifth valve is connected to a PLC controller.

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