Explosion-proof exhaust system of high-power gas engine

Abstract

The utility model provides an anti-explosion exhaust system of a high-power gas engine, and belongs to the technical field of engines. Comprising a gas engine, a supercharger is connected to the gas engine, an exhaust pipe is connected to an outlet of the supercharger through an expansion joint, an air dilution pipeline assembly is connected to the expansion joint, an oxygen sensor is arranged on the exhaust pipe, the air dilution pipeline assembly and the oxygen sensor are both connected with a control module, and anti-explosion valves are arranged at elbow portions of the exhaust pipe. According to the utility model, air is blown into the exhaust pipe, unburned gas is diluted, and meanwhile, the explosion-proof valve is arranged at the elbow part of the exhaust pipe, so that the problem that the unburned gas explodes in the exhaust of the gas engine is solved, and the explosion risk is reduced to the minimum.

Description

Technical Field

[0001] The utility model belongs to the technical field of engines, and in particular relates to an explosion-proof exhaust system for a high-power gas engine. Background Art

[0002] When a gas engine fails to ignite or is in an abnormal state, or is running at idle speed, the gas in the cylinder cannot be fully burned, resulting in a large amount of unburned natural gas in the exhaust gas, which is very likely to explode at high temperatures, posing a safety hazard. In particular, high-power natural gas engines have large displacement and high gas consumption. When the combustion is incomplete, the gas content in the exhaust gas is high, and the risk of explosion is higher, with more serious consequences.

[0003] The exhaust of gas engines is generally discharged from the outlet of the supercharger and directly discharged into the atmosphere. Users with noise requirements will require the addition of a muffler on the exhaust pipe. High-power gas engines are generally installed indoors, and the exhaust needs to be connected from indoors to outdoors. The exhaust pipeline is relatively long, generally more than 10m. At the same time, high-power gas engines have a large exhaust volume. For example, the exhaust pipe diameter of a 3000KW gas engine is generally above DN600, and the total length is calculated as 10m. The volume of the exhaust pipe is as high as 2.8 cubic meters. Once the unburned gas in the pipe explodes, the consequences will be serious. Therefore, it is necessary to propose improvements. Utility Model Content

[0004] The technical problem solved by the utility model is to provide an explosion-proof exhaust system for a high-power gas engine. The utility model aims to dilute unburned gas by blowing air into the exhaust pipe, and at the same time install an explosion-proof valve at the elbow of the exhaust pipe to solve the problem of explosion of unburned gas in the exhaust of the gas engine, thereby reducing the risk of explosion to a minimum.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A high-power gas engine explosion-proof exhaust system comprises a gas engine, wherein the gas engine is connected to a supercharger, an outlet of the supercharger is connected to an exhaust pipe via an expansion joint, an air dilution pipeline assembly is connected to the expansion joint, an oxygen sensor is provided on the exhaust pipe, the air dilution pipeline assembly and the oxygen sensor are both connected to a control module, and explosion-proof valves are provided at the elbows of the exhaust pipe.

[0007] To further limit the above technical solution, the air dilution pipeline assembly includes an air pipeline, a blower and an electrically controlled stop valve, the outlet end of the air pipeline is connected to the expansion joint, the inlet end of the air pipeline is connected to the blower, the air pipeline is connected to the electrically controlled stop valve, and the blower and the electrically controlled stop valve are both electrically connected to the control module.

[0008] As a further limitation of the above technical solution, the outlet end of the air pipeline passes through the wall of the expansion joint and the outlet flow direction is the same as the exhaust flow direction, and the outlet end of the air pipeline is configured as a gradual nozzle shape.

[0009] As a further limitation of the above technical solution, the oxygen sensor is a zirconium oxide oxygen sensor.

[0010] As a further limitation of the above technical solution, a muffler is connected to the outlet end of the exhaust pipe.

[0011] As a further limitation of the above technical solution, a rain cap is provided on the upper portion of the outlet of the muffler.

[0012] The advantages of this utility model compared with the prior art:

[0013] 1. This solution uses an oxygen sensor to detect the oxygen content in the exhaust pipe and calculate the air-fuel ratio. When the air-fuel ratio is lower than the set value, the blower is automatically controlled to blow air into the exhaust pipe to dilute the unburned gas and avoid explosion. At the same time, an explosion-proof valve is installed at the elbow of the exhaust pipe to minimize the risk of explosion and ensure safety.

[0014] 2. This solution monitors the air-fuel ratio in the exhaust pipe and uses a blower to purge the exhaust pipe to dilute the combustible gas and avoid explosion. This system has the characteristics of low manufacturing cost, simple operation and wide application range, and can effectively reduce the danger level of gas engine operation;

[0015] 3. This solution is used in the exhaust system of gas engines, especially for high-power gas engines, gas engines with long exhaust pipes and large volumes. It monitors the air-fuel ratio in the exhaust pipe in real time. Once the gas is too concentrated, the blower is started immediately to dilute the gas in the pipe to reduce the risk of explosion. At the same time, a special explosion-proof valve is installed to minimize the risk of explosion, providing double insurance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The utility model is a schematic structural diagram of an explosion-proof exhaust system for a high-power gas engine. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0019] See also Figure 1 , describe the embodiments of the present utility model in detail.

[0020] Example: Explosion-proof exhaust system for high-power gas engines, see Figure 1 As shown, it includes a gas engine 1, the gas engine 1 is connected to a supercharger 2, the outlet of the supercharger 2 is connected to an exhaust pipe 11 through an expansion joint 3, the expansion joint 3 is connected to an air dilution pipeline assembly 4, the exhaust pipe 11 is provided with an oxygen sensor 5, the air dilution pipeline assembly 4 and the oxygen sensor 5 are both connected to a control module 10, and the elbow portion 12 of the exhaust pipe 11 is provided with an explosion-proof valve 13.

[0021] In this embodiment, an oxygen sensor is used to detect the oxygen content in the exhaust pipe, and the control module calculates the air-fuel ratio based on the data of the oxygen sensor. When the air-fuel ratio is lower than the set value, the air dilution pipeline assembly is automatically controlled to blow air into the exhaust pipe to dilute the unburned gas and avoid explosion.

[0022] In the above-mentioned implementation structure, the air-fuel ratio of the gas engine is generally designed with a target value, such as lean combustion is generally designed at 2.0. During normal combustion, the amount of air in the exhaust is small, that is, the amount of oxygen molecules is small. When abnormal conditions such as non-combustion and ignition failure occur, the amount of gas in the exhaust will increase and the air-fuel ratio will decrease, such as to 1.5. The oxygen sensor is used to monitor the oxygen content in the exhaust pipe, and the signal is input to the control module. The control module can calculate the air-fuel ratio at this time and determine whether it is necessary to start the air dilution pipeline assembly for air blowing and dilution.

[0023] In the above implementation structure, the system installs a special explosion-proof valve at the elbow of the exhaust pipe, which can reduce the explosion risk to a minimum once an explosion occurs.

[0024] This system is used in the exhaust system of gas engines, especially for high-power gas engines, gas engines with long exhaust pipes and large volumes. It monitors the air-fuel ratio in the exhaust pipe in real time. Once the gas is too concentrated, the blower is started immediately to dilute the gas in the pipe to reduce the risk of explosion. At the same time, a special explosion-proof valve is installed to minimize the risk of explosion, providing double insurance.

[0025] In a specific embodiment, the air dilution pipeline assembly 4 includes an air pipeline 6, a blower 7 and an electrically controlled stop valve 8, the outlet end of the air pipeline 6 is connected to the expansion joint 3, the inlet end of the air pipeline 6 is connected to the blower 7, the air pipeline 6 is connected to the electrically controlled stop valve 8, and the blower 7 and the electrically controlled stop valve 8 are both electrically connected to the control module 10.

[0026] In the above embodiment, when the air-fuel ratio is lower than the set value, the control module receives the signal of the oxygen sensor and controls the start and stop of the blower and the opening and closing of the electric stop valve. The blower is controlled to blow air into the exhaust pipe to dilute the unburned gas and avoid explosion. In order to prevent the exhaust gas from flowing out of the air pipe in the reverse direction when the blower stops working, an electric stop valve is installed in front of the blower to control the air on and off.

[0027] In a specific embodiment, the outlet end of the air pipeline 6 passes through the wall of the expansion joint 3 and the outlet flow direction is the same as the exhaust flow direction. The outlet end of the air pipeline 6 is set to a gradual nozzle shape 9.

[0028] In the above embodiment, by designing a gradual nozzle shape at the outlet of the air pipeline, the air flow rate can be increased and the flow direction range can be controlled.

[0029] In a specific implementation, the oxygen sensor 5 is a zirconium oxide oxygen sensor for detecting the exhaust oxygen content in the pipe.

[0030] In a specific embodiment, a muffler 14 is connected to the outlet end of the exhaust pipe 11 to eliminate noise.

[0031] In a specific embodiment, a rain cap 15 is provided at the upper portion of the outlet of the muffler 14, and the rain cap is used to prevent rainwater from entering the muffler.

[0032] In this system, the control module receives the signal from the oxygen sensor and controls the start and stop of the blower and the opening and closing of the electric stop valve. The following parameters can be set in the control module:

[0033] 1) The air-fuel ratio setting value for starting the blower and starting purging, such as 1.8;

[0034] 2) The blower stops running and the air-fuel ratio setting value for stopping purge is 2.5;

[0035] 3) The interval from blower start to the opening of the electric stop valve, such as 1s. It takes a certain amount of time to build up wind pressure after the blower starts. This parameter can avoid exhaust backflow during the blower start-up period.

[0036] 4) The interval from the closing of the electric stop valve to the stopping of the blower, such as 2s.

[0037] The implementation process of the system is as follows:

[0038] When the engine has abnormal combustion or ignition failure, the air-fuel ratio in the exhaust pipe changes. The system uses an oxygen sensor to monitor the air-fuel ratio in the exhaust pipe. When the air-fuel ratio is lower than the system set value, such as the engine combustion target air-fuel ratio of 2.0, the purge start can be set at 1.8. If it is judged that purge is needed, a signal is sent to start the blower first, and after a set interval time, such as 1s, the electric stop valve is opened to start purge and dilute the gas in the exhaust pipe. When the air-fuel ratio increases to the set value for stopping purge, such as 2.5, the electric stop valve is closed, and after a set interval time, such as 2s, the blower is closed to complete a purge cycle.

[0039] This system can monitor the air-fuel ratio in the exhaust pipe of the gas engine in real time. Once it is lower than the set value, the blower will be started for purging to improve the safety of engine operation. The structure is simple, and the modification of the existing exhaust pipe is small, saving modification costs. A special explosion-proof valve is designed to minimize the risk of explosion in the event of an explosion. The monitoring parameters of the system, such as the air-fuel ratio and the blower start interval, can be set by yourself, and it has a wide range of applicability.

[0040] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0041] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A high-power gas engine explosion-proof exhaust system, comprising a gas engine (1), wherein the gas engine (1) is connected to a supercharger (2), and the outlet of the supercharger (2) is connected to an exhaust pipe (11) via an expansion joint (3), wherein: The expansion joint (3) is connected to an air dilution pipeline assembly (4), the exhaust pipe (11) is provided with an oxygen sensor (5), the air dilution pipeline assembly (4) and the oxygen sensor (5) are both connected to a control module (10), and an explosion-proof valve (13) is provided at an elbow portion (12) of the exhaust pipe (11).

2. The explosion-proof exhaust system for a high-power gas engine according to claim 1 is characterized in that: The air dilution pipeline assembly (4) comprises an air pipeline (6), a blower (7) and an electrically controlled stop valve (8); the outlet end of the air pipeline (6) is in communication with the expansion joint (3); the inlet end of the air pipeline (6) is connected to the blower (7); the air pipeline (6) is connected to the electrically controlled stop valve (8); and the blower (7) and the electrically controlled stop valve (8) are both electrically connected to a control module (10).

3. The explosion-proof exhaust system for a high-power gas engine according to claim 2 is characterized in that: The outlet end of the air pipeline (6) passes through the wall of the expansion joint (3) and the outlet flow direction is the same as the exhaust flow direction. The outlet end of the air pipeline (6) is configured as a gradual nozzle shape (9).

4. The explosion-proof exhaust system for a high-power gas engine according to claim 1, characterized in that: The oxygen sensor (5) is a zirconium oxide type oxygen sensor.

5. The explosion-proof exhaust system for a high-power gas engine according to claim 1, characterized in that: A muffler (14) is connected to the outlet end of the exhaust pipe (11).

6. The explosion-proof exhaust system for a high-power gas engine according to claim 5, characterized in that: A rain shield cap (15) is provided on the upper portion of the outlet of the muffler (14).

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