High-compression-ratio multi-stage adjustable injection system for recycling sulfur-containing natural gas tail gas
The multi-stage adjustable injection system solves the problems of high energy consumption and poor purification effect caused by single-stage compression and single injection, realizing efficient hydrogen sulfide purification and exhaust gas resource utilization, reducing equipment burden and environmental pollution.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SUZHOU HANXIAO PLASMA TECH CO LTD
- Filing Date
- 2025-07-02
- Publication Date
- 2026-05-26
AI Technical Summary
Existing technologies for treating sulfur-containing natural gas tail gas suffer from high energy consumption due to single-stage compression, rapid rise in gas temperature, insufficient mixing due to single injection, poor purification effect of hydrogen sulfide, and lack of resource utilization, leading to increased equipment burden and environmental pollution.
It adopts a high compression ratio multi-stage adjustable injection system, including a reflux valve, a primary injector and a secondary injector. Utilizing a venturi structure and swirl vane design, combined with jacket cooling, it achieves multi-stage gas mixing and temperature control. The position of the injection needle is adjusted in real time by a pneumatic actuator, which improves the mixing uniformity and equipment life.
It reduces compression energy consumption, improves hydrogen sulfide purification efficiency, reduces harmful substance emissions, achieves effective utilization of exhaust gas resources, and reduces equipment burden and operating costs.
Smart Images
Figure CN224270716U_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of natural gas tail gas treatment technology, specifically relating to a high compression ratio multi-stage adjustable injection system for recovering sulfur-containing natural gas tail gas. Background Technology
[0002] In the natural gas extraction and processing, the treatment of sulfur-containing natural gas tail gas is a crucial step. Existing technologies often employ simple single-stage compression and single-injection treatment methods. Single-stage compression struggles to compress the tail gas to the ideal pressure, limiting subsequent treatment efficiency. Single-injection treatment cannot adequately remove harmful substances like hydrogen sulfide from the tail gas, resulting in poor purification. From a technological perspective, single-stage compression causes a rapid increase in gas temperature when increasing pressure, increasing equipment load and energy consumption, and potentially affecting subsequent gas treatment. Furthermore, single-injection treatment leaves a large amount of harmful substances in the tail gas due to incomplete reactions; direct emission would cause serious environmental pollution. Secondary treatment would increase costs and procedures. Moreover, most existing treatment systems lack awareness of recycling useful components in the tail gas, leading to resource waste.
[0003] Therefore, existing technologies for treating sulfur-containing natural gas tail gas mostly employ single-stage compression and single injection methods, which have the following problems:
[0004] 1. Single-stage compression has high energy consumption and causes a rapid rise in gas temperature, which affects the lifespan of the equipment;
[0005] 2. Insufficient mixing due to single-jet spraying results in poor hydrogen sulfide purification.
[0006] 3. Lack of utilization of exhaust gas resources leads to waste. Utility Model Content
[0007] The purpose of this invention is to provide a high compression ratio multi-stage adjustable injection system for recovering sulfur-containing natural gas tail gas. By increasing the compression ratio of the sulfur-containing natural gas tail gas, the energy consumption and equipment burden during the compression process are reduced, allowing the tail gas to reach a pressure state more suitable for subsequent processing.
[0008] The specific technical solution adopted in this utility model is as follows:
[0009] A high-compression-ratio multi-stage adjustable injection system for recovering sulfur-containing natural gas tail gas includes a reflux valve, a primary injector, and a secondary injector. The reflux valve is used to regulate the flow rate of the sulfur-containing natural gas tail gas. The primary and secondary injectors each include a pneumatic actuator, a nozzle, a steam chamber, a nozzle, and a mixing chamber. A jacket is provided on the outside of the mixing chamber for cooling the mixing chamber. A swirl vane is provided inside the nozzle, and the angle between the vane blade and the central axis of the nozzle is 30°-60°.
[0010] In a preferred embodiment, both the primary injector and the secondary injector are designed based on the Venturi principle, and the nozzle diameter of the secondary injector is smaller than that of the primary injector.
[0011] In a preferred embodiment, the jacket uses circulating cooling water or inert gas as a cooling medium to reduce the temperature of the mixing chamber.
[0012] In a preferred embodiment, the nozzle is linked with a pneumatic actuator via a linear displacement sensor to achieve real-time closed-loop control of the jet velocity.
[0013] The technical effects achieved by this utility model are as follows:
[0014] This utility model uses a multi-stage compression structure consisting of a primary ejector and a secondary ejector, and a swirl vane is installed inside the nozzle of the ejector to make the ejected gas flow rotate, thereby improving the uniformity of natural gas mixing.
[0015] This invention uses a jacket installed on the outside of the mixing chamber. The low-temperature medium flowing through the jacket can cool the mixing chamber, thereby preventing damage from overheating and extending the service life of the equipment. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the overall structure of this practical tool;
[0017] Figure 2 This is an enlarged structural schematic diagram of the practical first-stage injector;
[0018] Figure 3 This is a practical book Figure 2 Enlarged structural diagram at point A in the middle;
[0019] Figure 4 This is an enlarged isometric view of the nozzle of this practical application.
[0020] The attached diagram lists the components represented by each number as follows:
[0021] 1. Return valve; 2. Primary ejector; 3. Secondary ejector; 4. Pneumatic actuator; 5. Needle; 6. Steam chamber; 7. Nozzle; 8. Mixing chamber; 9. Jacket; 71. Swirl vane. Detailed Implementation
[0022] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.
[0023] Many specific details are set forth in the following description in order to provide a full understanding of this utility model. However, this utility model may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.
[0024] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of this utility model. The phrase "in a preferred embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that mutually excludes other embodiments.
[0025] Secondly, this utility model is described in detail with reference to the schematic diagrams. When detailing the embodiments of this utility model, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not according to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of this utility model. In addition, actual manufacturing should include the three-dimensional spatial dimensions of length, width, and depth.
[0026] Please see the appendix Figure 1 and Figure 2 As shown, this utility model provides a high compression ratio multi-stage adjustable injection system for recovering sulfur-containing natural gas tail gas, including a return valve 1, a primary injector 2, and a secondary injector 3. The return valve 1 is used to adjust the flow rate of the sulfur-containing natural gas tail gas. The primary injector 2 and the secondary injector 3 each include a pneumatic actuator 4, a nozzle 5, a steam chamber 6, a nozzle 7, and a mixing chamber 8. A jacket 9 is provided on the outside of the mixing chamber 8 for cooling the mixing chamber 8. The primary injector 2 and the secondary injector 3 are both designed based on the Venturi structure principle, and the diameter of the nozzle 7 of the secondary injector 3 is smaller than the diameter of the nozzle 7 of the primary injector 2.
[0027] In this embodiment, the first-stage injector 2 adopts an innovatively designed multi-stage online adjustable injector, with the internal nozzle 7 equipped with a swirl vane 71. High-pressure natural gas is introduced through a specific pipeline. Inside the first-stage injector 2, the high-pressure natural gas flows at high speed. Due to the action of the swirl vane 71, the fluid injection angle is increased, allowing the high-pressure natural gas to be more fully and initially mixed with the sulfur-containing natural gas tail gas. With the help of the energy of the high-pressure natural gas, the tail gas is initially dispersed and mixed, creating conditions for subsequent deep processing.
[0028] The gas initially mixed by the first-stage injector 2 enters the steam chamber 6 of the second-stage injector 3. Like the first-stage injector 2, the second-stage injector 3 injects and mixes the gas again based on the Venturi principle, further enhancing the mixing effect. Through the progressive processing of the two-stage injectors, the exhaust gas components are made to come into more full contact and mix with the high-pressure natural gas, so that the gas mixing uniformity reaches a high level and meets the requirements for connection to the natural gas pipeline network.
[0029] Please see Figure 3 and Figure 4 As shown, a swirl vane 71 is provided inside the nozzle 7, and the angle between the blade of the swirl vane 71 and the central axis of the nozzle 7 is 30°-60°.
[0030] The design of nozzle 7 with swirl vane 71 increases the contact area between high-pressure natural gas and sulfur-containing natural gas tail gas, increases the injection angle, achieves more thorough mixing, significantly enhances the purification reaction effect, and improves the quality of tail gas treatment.
[0031] Please see Figure 1 and Figure 2 As shown, cooling water or inert gas is circulated inside the jacket 9 as the cooling medium to reduce the temperature of the mixing chamber 8;
[0032] In this embodiment, jackets 9 are installed on the outside of the mixing chambers 8 of the primary ejector 2 and the secondary ejector 3. The cooling medium enters through the inlet of the jacket 9 of the primary ejector 2 and cools the mixing chamber 8 of the primary ejector 2 as it flows through the jacket 9. Since the outlet of the jacket 9 of the primary ejector 2 and the inlet of the jacket 9 of the secondary ejector 3 are connected, the cooling medium flowing out from the outlet of the jacket 9 of the primary ejector 2 flows back into the inlet of the jacket 9 of the secondary ejector 3 and cools the mixing chamber 8 of the secondary ejector 3 as it flows through the jacket 9 of the secondary ejector 3. Finally, it flows back into the cooling equipment from the outlet of the jacket 9 of the secondary ejector 3. The inert gas can be a substance such as nitrogen.
[0033] The nozzle 5 is linked with the pneumatic actuator 4 through a linear displacement sensor to achieve real-time closed-loop control of the jet flow rate.
[0034] The multi-stage online adjustable injector of this device can adjust the position of the nozzle 5 in real time according to the changes in demand through the pneumatic actuator 4. When the nozzle 5 moves forward, the contact area between the nozzle 5 and the exhaust steam is reduced, and the exhaust steam flow rate is accelerated; conversely, when the nozzle 5 moves backward, the contact area is increased and the flow rate is reduced. This design greatly improves the system's flexibility and adaptability, breaking through the limitations of traditional single-stage injection.
[0035] For natural gas processing of different scales, the following different implementation methods exist:
[0036] Example 1:
[0037] For applications in medium-sized natural gas processing plants: In such plants, the flow rate of sulfur-containing natural gas tail gas is 500 cubic meters per hour, with a hydrogen sulfide content of 2%. After system startup, the tail gas is connected to the processing system. Return valve 1 adjusts according to real-time operating conditions to ensure a stable tail gas flow rate of 450 cubic meters per hour entering the processing stage. High-pressure natural gas is introduced into the first-stage ejector 2 at a stable pressure and flow rate. Under the Venturi effect, the tail gas and high-pressure natural gas are thoroughly mixed. The gas exiting the first-stage ejector 2 enters the second-stage ejector 3 for further mixing. The resulting gas has a significantly reduced hydrogen sulfide content, meeting the natural gas pipeline connection standards, and can be successfully connected to the pipeline for transportation. This process transforms sulfur-containing tail gas into a valuable resource, saving costs and reducing harmful gas emissions.
[0038] Example 2:
[0039] For small-scale natural gas extraction sites: At these sites, the flow rate of sulfur-containing natural gas tail gas is 100 cubic meters per hour, with a hydrogen sulfide content of 1.5% (volume fraction). The sulfur-containing natural gas tail gas is fed into the system. Return valve 1 is fine-tuned according to the equipment's operating status to stabilize the tail gas flow rate entering the processing stage at 90 cubic meters per hour. High-pressure natural gas enters the first-stage injector 2 according to design parameters for initial mixing with the tail gas, followed by enhanced mixing in the second-stage injector 3. The hydrogen sulfide content of the treated tail gas is significantly reduced, allowing for successful connection to the nearby natural gas pipeline network.
[0040] The working principle of this utility model is as follows: Sulfur-containing natural gas tail gas enters the steam chamber 6 of the first-stage injector 2. Before entering the steam chamber 6, the sulfur-containing natural gas tail gas undergoes partial reflux regulation through the reflux valve 1 to adapt to different operating conditions. High-pressure natural gas is transported through pipelines and injected into the steam chamber 6 of the first-stage injector 2 through the nozzle 7. In the steam chamber 6 of the first-stage injector 2, the high-pressure natural gas flows at high speed, forming a negative pressure area. Utilizing the Venturi effect, the sulfur-containing natural gas tail gas is drawn in and initially mixed. Simultaneously, when the high-pressure natural gas is ejected from the nozzle 7, the injection angle is increased by the swirl vane 71, causing the high-pressure natural gas in the steam chamber 6 and the drawn-in sulfur-containing natural gas tail gas to rotate. After flowing into the mixing chamber 8, more uniform mixing is achieved. Because the tail end of the mixing chamber 8 of the first-stage injector 2 is connected to the second-stage injector 3... The steam chamber 6 of the secondary ejector 3 is connected, and the steam chamber 6 of the secondary ejector 3 is also connected to the high-pressure natural gas through a pipeline. When the nozzle 7 of the secondary ejector 3 injects high-pressure natural gas into the steam chamber 6, the high-speed flow of the high-pressure natural gas in the steam chamber 6 of the secondary ejector 3 creates a negative pressure in the steam chamber 6 of the secondary ejector 3, which will draw in the gas mixed in the mixing chamber 8 of the primary ejector 2. The gas drawn in is mixed again in the mixing chamber 8 of the secondary ejector 3, and finally enters the natural gas pipeline network from the tail end of the mixing chamber 8 of the secondary ejector 3, realizing the treatment and transportation of sulfur-containing natural gas tail gas.
[0041] The above description is merely a preferred embodiment of this utility model. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model. Structures, devices, and operating methods not specifically described or explained in this utility model, unless otherwise specified or limited, shall be implemented using conventional methods in the art.
Claims
1. A high-compression-ratio, multi-stage adjustable injection system for recovering sulfur-containing natural gas tail gas, characterized in that: It includes a reflux valve (1), a primary injector (2) and a secondary injector (3), wherein the reflux valve (1) is used to regulate the flow rate of sulfur-containing natural gas tail gas, and the primary injector (2) and the secondary injector (3). Both the first-stage injector (2) and the second-stage injector (3) include a pneumatic actuator (4), a nozzle (5), a steam chamber (6), a nozzle (7), and a mixing chamber (8). A jacket (9) is provided on the outside of the mixing chamber (8), and the jacket (9) is used to cool the mixing chamber (8). The nozzle (7) is provided with a swirl vane (71), and the angle between the blade of the swirl vane (71) and the central axis of the nozzle (7) is 30°-60°.
2. The high compression ratio multi-stage adjustable injection system for recovering sulfur-containing natural gas tail gas according to claim 1, characterized in that: Both the primary injector (2) and the secondary injector (3) are designed based on the Venturi structure principle, and the nozzle (7) diameter of the secondary injector (3) is smaller than the nozzle (7) diameter of the primary injector (2).
3. The high compression ratio multi-stage adjustable injection system for recovering sulfur-containing natural gas tail gas according to claim 1, characterized in that: The jacket (9) uses circulating cooling water or inert gas as a cooling medium to reduce the temperature of the mixing chamber (8).
4. The high compression ratio multi-stage adjustable injection system for recovering sulfur-containing natural gas tail gas according to claim 1, characterized in that: The nozzle (5) is linked with the pneumatic actuator (4) through a linear displacement sensor to achieve real-time closed-loop control of the jet flow rate.