Truck loading VOC tail gas pressurization system

Abstract

The utility model discloses a loading VOC (volatile organic compound) tail gas pressurization system. The loading VOC tail gas pressurization system comprises a nitrogen input pipeline, a loading tail gas output pipeline, an ejector and an ejector outlet pipeline, the nitrogen input pipeline and the loading tail gas output pipeline are respectively connected with the inlet end of the ejector; wherein the nitrogen input pipeline is externally connected with a nitrogen source, and the other end of the loading tail gas output pipeline is connected with a loading crane pipe and used for guiding out loading tail gas; the outlet end of the ejector is connected with an ejector outlet pipeline and used for outputting the loading tail gas. According to the loading VOC tail gas pressurizing system, the ejector is adopted for pressurizing loading tail gas, diluted nitrogen serves as power gas, and the intrinsic safety of the system is ensured. An oxygen online analysis unit is arranged at an outlet of the ejector, nitrogen flow is controlled in a cascade mode based on a flowmeter, nitrogen consumption is reduced, and safety of the system is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of chemical industry, and particularly relates to a VOC tail gas pressurization system for loading vehicles. Background Art

[0002] As environmental protection requirements are increasingly stringent, regulations require that all volatile flammable liquid material loading systems should be equipped with oil and gas recovery facilities. Since flammable liquids are currently loaded mainly from the top, and empty tank trucks are usually filled with air, the flammable gas generated during the loading process forms a mixed gas with the air in the tank truck, in which the flammable gas concentration is 30% to 45%, and the rest is air. The mixed gas is flammable and explosive, and is very dangerous.

[0003] The pressure of the loaded exhaust gas is generally lower than 4KPaG, and it usually needs to be pressurized by a fan before entering the exhaust gas treatment facility. The fan must be selected according to the explosion zone of the medium and the external environment to meet the explosion-proof requirements. The fan cannot generate sparks when running. The fan usually used for exhaust gas pressurization is a potential fire source. The fan needs to meet the 0 zone to meet the safety requirements, but currently no fan can meet the 0 zone requirements. Therefore, there is a great risk in the process of pressurization and transportation of the exhaust gas generated by loading. Utility Model Content

[0004] The purpose of the utility model is to overcome the problems of the prior art and disclose a vehicle-mounted VOC tail gas pressurization system.

[0005] The purpose of the utility model is achieved through the following technical solutions:

[0006] A VOC tail gas pressurization system for loading a vehicle, the VOC tail gas pressurization system for loading a vehicle comprising: a nitrogen input pipeline, a vehicle tail gas output pipeline, an ejector and an ejector outlet pipeline;

[0007] The nitrogen input pipeline and the loading exhaust gas output pipeline are respectively connected to the inlet end of the ejector; wherein the nitrogen input pipeline is externally connected to a nitrogen source, and the other end of the loading exhaust gas output pipeline is connected to a loading crane pipe for completing the exhaust gas output of the loading;

[0008] The outlet end of the injector is connected to the injector outlet pipeline to complete the output of the vehicle exhaust gas.

[0009] According to a preferred embodiment, an oxygen online analysis unit is connected to the ejector outlet pipeline to measure the oxygen content in the gas output from the ejector outlet pipeline.

[0010] According to a preferred embodiment, the nitrogen input pipeline is provided with a second regulating valve for completing nitrogen input regulation.

[0011] According to a preferred embodiment, a flow meter is also provided on the nitrogen input pipeline to monitor the nitrogen input flow rate.

[0012] According to a preferred embodiment, an emergency shut-off valve is also provided at the end of the ejector outlet pipeline.

[0013] According to a preferred embodiment, the ejector outlet pipeline is also connected to a vent pipeline for venting the exhaust gas from the vehicle.

[0014] According to a preferred embodiment, a vent valve is provided on the vent pipeline.

[0015] According to a preferred embodiment, the loading exhaust gas output pipeline is further provided with a loading exhaust gas pressure monitoring unit for completing gas pressure monitoring on the loading exhaust gas output pipeline.

[0016] According to a preferred embodiment, the VOC exhaust gas pressurizing system for loading also includes a reflux pipeline, one end of which is connected to the ejector outlet pipeline, and the other end is connected to the loading exhaust gas output pipeline, for completing gas pressure regulation on the loading exhaust gas output pipeline.

[0017] According to a preferred embodiment, a first regulating valve is provided on the return line.

[0018] The above-mentioned main scheme of the utility model and its further optional schemes can be freely combined to form multiple schemes, all of which are schemes that can be adopted and claimed for protection by the utility model. After understanding the scheme of the utility model, those skilled in the art can understand that there are many combinations based on the existing technology and common knowledge, all of which are technical schemes to be protected by the utility model, and they are not exhaustively listed here.

[0019] Beneficial effects of the utility model:

[0020] This VOC tail gas pressurization system uses an ejector to pressurize the tail gas, and uses diluted nitrogen as the power gas. The entire system has no electrical equipment and rotating equipment, ensuring the intrinsic safety of the system. An oxygen online analysis unit is set at the ejector outlet and the nitrogen flow is controlled based on the flow meter cascade, which reduces nitrogen consumption and increases the safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of the VOC tail gas pressurization system for loading vehicles of the utility model;

[0022] Among them, 1-nitrogen input pipeline, 2-loading exhaust gas output pipeline, 3-injector, 4-injector outlet pipeline, 5-oxygen online analysis unit, 6-vent valve, 7-emergency shut-off valve, 8-first regulating valve, 9-loading exhaust gas pressure monitoring unit, 10-loading crane pipe, 11-second regulating valve, 12-flow meter. DETAILED DESCRIPTION

[0023] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0024] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0025] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0026] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0027] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In addition, the present utility model should point out that, in the present utility model, if the specific structure, connection relationship, position relationship, power source relationship, etc. are not specifically written out, the structure, connection relationship, position relationship, power source relationship, etc. involved in the present utility model are all known by technical personnel in this field on the basis of existing technology without creative work.

[0029] refer to Figure 1 As shown in the figure, a VOC tail gas pressurization system for loading a vehicle is shown, and the VOC tail gas pressurization system for loading a vehicle comprises: a nitrogen input pipeline 1, a tail gas output pipeline 2, an injector 3 and an injector outlet pipeline 4.

[0030] The nitrogen input pipeline 1 and the loading exhaust gas output pipeline 2 are respectively connected to the inlet end of the ejector 3; wherein, the nitrogen input pipeline 1 is externally connected to a nitrogen source, and the other end of the loading exhaust gas output pipeline 2 is connected to a loading crane pipe 10 for completing the exhaust gas discharge of the loading exhaust gas.

[0031] Among them, at the inlet of the ejector 3, nitrogen and the loading exhaust gas from the loading crane pipe 10 enter the ejector 3 respectively, and the nitrogen, as a power source, pressurizes the loading exhaust gas through the ejector and inertizes and dilutes the loading exhaust gas.

[0032] The outlet end of the injector 3 is connected to the injector outlet pipeline 4 for completing the output of the vehicle exhaust gas.

[0033] Preferably, an oxygen online analysis unit 5 is connected to the ejector outlet pipeline 4 to measure the oxygen content in the gas output from the ejector outlet pipeline 4 to protect the system.

[0034] Preferably, the nitrogen input pipeline 1 is provided with a second regulating valve 11 for completing nitrogen input regulation. The nitrogen input pipeline 1 is also provided with a flow meter 12 for completing nitrogen input flow monitoring. Based on the oxygen content in the outlet pipeline of the ejector outlet pipeline 4 measured by the oxygen online analysis unit 5 and the nitrogen flow measured by the flow meter 12, precise control of the input nitrogen is completed through the second regulating valve 11.

[0035] Preferably, an emergency shut-off valve 7 is also provided at the end of the ejector outlet pipeline 4. A vent pipeline is also connected to the ejector outlet pipeline 4 to discharge the exhaust gas from the vehicle. A vent valve 6 is provided on the vent pipeline.

[0036] When the oxygen online analysis unit 5 detects that the oxygen content in the ejector outlet pipeline 4 is too high, the emergency shut-off valve 7 is interlocked and closed, and the vent valve 6 is opened to discharge the gas.

[0037] Preferably, the loading exhaust gas output pipeline 2 is also provided with a loading exhaust gas pressure monitoring unit 9 for completing gas pressure monitoring on the loading exhaust gas output pipeline 2 .

[0038] Furthermore, the loading VOC tail gas pressurization system also includes a reflux pipeline, one end of which is connected to the ejector outlet pipeline 4, and the other end is connected to the loading tail gas output pipeline 2, for completing the gas pressure regulation on the loading tail gas output pipeline 2. A first regulating valve 8 is provided on the reflux pipeline.

[0039] If the pressure of the vehicle exhaust gas output pipeline 2 is low, the fluid flow rate can be adjusted back through the first regulating valve 8 to complete the adjustment of the injector 3 inlet pressure.

[0040] The VOC tail gas pressurization system for loading vehicles uses an ejector to pressurize the tail gas for loading vehicles, and uses diluted nitrogen as the power gas. The entire system has no electrical equipment and rotating equipment, ensuring the intrinsic safety of the system. An oxygen online analysis unit 5 is set at the ejector outlet and the nitrogen flow rate is cascade-controlled based on a flow meter 12, which reduces nitrogen consumption and increases the safety of the system.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A VOC tail gas pressurization system for loading vehicles, characterized in that: The VOC tail gas pressurization system for loading vehicles comprises: a nitrogen input pipeline (1), a tail gas output pipeline (2), an ejector (3) and an ejector outlet pipeline (4); The nitrogen input pipeline (1) and the loading exhaust gas output pipeline (2) are respectively connected to the inlet end of the ejector (3); wherein the nitrogen input pipeline (1) is externally connected to a nitrogen source, and the other end of the loading exhaust gas output pipeline (2) is connected to a loading crane pipe (10) for completing the exhaust gas discharge from the loading vehicle; The outlet end of the injector (3) is connected to the injector outlet pipeline (4) to complete the output of vehicle exhaust gas.

2. The VOC tail gas pressurization system for loading vehicles according to claim 1, characterized in that: The ejector outlet pipeline (4) is connected to an oxygen online analysis unit (5) for measuring the oxygen content in the gas output from the ejector outlet pipeline (4).

3. The VOC tail gas pressurization system for loading vehicles according to claim 1 or 2, characterized in that: The nitrogen input pipeline (1) is provided with a second regulating valve (11) for completing nitrogen input regulation.

4. The VOC tail gas pressurization system for loading vehicles according to claim 3, characterized in that: The nitrogen input pipeline (1) is also provided with a flow meter (12) for monitoring the nitrogen input flow rate.

5. The VOC tail gas pressurization system for loading vehicles according to claim 2, characterized in that: An emergency shut-off valve (7) is also provided at the end of the ejector outlet pipeline (4).

6. The VOC tail gas pressurization system for loading vehicles according to claim 5, characterized in that: The ejector outlet pipeline (4) is also connected to a vent pipeline for venting the exhaust gas from the vehicle.

7. The VOC tail gas pressurization system for loading vehicles according to claim 6, characterized in that: The venting pipeline is provided with a venting valve (6).

8. The VOC tail gas pressurization system for loading vehicles according to claim 1, characterized in that: The loading exhaust gas output pipeline (2) is also provided with a loading exhaust gas pressure monitoring unit (9) for completing gas pressure monitoring on the loading exhaust gas output pipeline (2).

9. The VOC tail gas pressurization system for loading vehicles according to claim 8, characterized in that: The VOC tail gas pressurizing system for loading vehicles also includes a return pipeline, one end of which is connected to the ejector outlet pipeline (4) and the other end of which is connected to the tail gas output pipeline (2) for loading vehicles, so as to complete the gas pressure regulation on the tail gas output pipeline (2).

10. The VOC tail gas pressurization system for loading vehicles according to claim 9, characterized in that: A first regulating valve (8) is provided on the return pipeline.

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