A device for adjusting flue gas temperature

Abstract

This utility model belongs to the field of flue gas denitrification technology in gas power plants, and particularly relates to a device for adjusting flue gas temperature. It includes a main flue gas pipe, with an SCR denitrification device installed at the flue gas outlet. A gas distribution branch pipe is installed on the main flue gas pipe, including a gas delivery pipe. One end of the gas delivery pipe near the main flue gas pipe has an angled gas delivery connecting pipe, and the other end has a blower. An electric butterfly valve is installed on the gas delivery pipe. A temperature sensor is installed on the main flue gas pipe near the SCR device. Through its overall design, this utility model achieves precise temperature control, system simplification and cost reduction, improved safety, and enhanced environmental friendliness.

Description

Technical Field

[0001] This utility model belongs to the field of flue gas denitrification technology in gas power plants, and particularly relates to a device that can adjust the flue gas temperature. Background Technology

[0002] Gas-fired internal combustion engine power generation technology is widely used in coal mines of all sizes throughout China. The main pollutant emitted by these engines is NOx, which is relatively high without end-of-pipe control measures. Therefore, NOx emissions from gas-fired internal combustion engines have become a crucial area for industry pollution control. With the continuous development of science and technology, many gas-fired internal combustion engines in my country have adopted mature and efficient flue gas denitrification technology, namely Selective Catalytic Reduction (SCR).

[0003] Existing SCR denitrification devices in gas power plants typically employ a multi-to-one denitrification method, which combines the exhaust branch pipes of each gas internal combustion engine into the main exhaust pipe, and then into a central SCR denitrification device.

[0004] Most SCR denitrification units choose intermediate-temperature catalysts, which typically exhibit good activity and selectivity, efficiently converting NOx to N2 and H2O within their operating temperature range. This type of catalyst is technologically mature and performs stably in industrial applications. The operating temperature range of intermediate-temperature catalysts is generally around 260℃-420℃.

[0005] However, fluctuations in the gas supply can cause fluctuations in the power output of the gas-fired internal combustion engine, which in turn affects the exhaust gas temperature. Unstable exhaust gas temperature not only affects denitrification efficiency but also reduces system safety. If the exhaust gas temperature is too high, the intermediate-temperature catalyst may experience sintering, leading to decreased catalyst activity and a shortened lifespan.

[0006] In existing technologies, gas-fired internal combustion engines with high exhaust gas temperatures typically require additional cooling systems (such as air coolers or water cooling systems installed on the exhaust manifold) to regulate the exhaust gas temperature and reduce it to the suitable operating temperature of the catalyst. However, these additional cooling systems increase the complexity and cost of the system. Summary of the Invention

[0007] To address the aforementioned problems, this invention provides a device for adjusting the exhaust gas temperature.

[0008] To achieve the above objectives, the technical solution adopted by this utility model is as follows: This utility model provides a device for adjusting the exhaust temperature, including an exhaust main pipe, an SCR denitrification device installed at the exhaust outlet of the exhaust main pipe, a gas distribution branch pipe installed on the exhaust main pipe, the gas distribution branch pipe including a gas delivery pipe, an angled gas delivery connecting pipe installed at one end of the gas delivery pipe near the exhaust main pipe, a blower installed at the other end, an electric butterfly valve installed on the gas delivery pipe, and a temperature sensor installed on the exhaust main pipe near the SCR device.

[0009] Preferably, the connection angle between the included-angle gas delivery connecting pipe and the exhaust main pipe is 45°.

[0010] Preferably, the device also includes a denitrification control box, which is electrically connected to the electric butterfly valve, the blower, and the temperature sensor.

[0011] Preferably, an air filter is provided at the air inlet of the blower.

[0012] Compared with the prior art, the advantages and positive effects of this utility model are as follows:

[0013] This invention enables precise temperature control: through a closed-loop control strategy, the flue gas temperature is monitored and adjusted in real time to ensure that it is always within the optimal operating temperature range of the catalyst, thereby improving denitrification efficiency and extending the service life of the catalyst.

[0014] This invention simplifies and reduces costs: it eliminates the need for additional air coolers or water cooling systems, reducing system complexity and costs; at the same time, it avoids problems such as water consumption and water treatment caused by using water cooling systems.

[0015] This invention enhances safety: during the start-up and low-load operation of the gas internal combustion engine, the electric butterfly valve prevents high-temperature flue gas from damaging the blower, thus improving the system's safety.

[0016] This invention enhances environmental friendliness: it does not rely on water resources for cooling, has less impact on the environment, and meets environmental protection requirements. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of the structure of an adjustable flue gas temperature device provided in Example 1;

[0019] Figure 2 A schematic diagram of the structure of an adjustable flue gas temperature device provided in Embodiment 1 (from another angle);

[0020] Figure 3 An enlarged view of the connection angle between the gas delivery connecting pipe and the main exhaust pipe in an adjustable exhaust temperature system provided in Example 1;

[0021] In the above diagrams, 1-exhaust main pipe, 2-gas distribution branch pipe, 3-electric butterfly valve, 4-blower, 5-denitrification control box, 6-temperature sensor, 7-air filter. Detailed Implementation

[0022] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0023] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed in the following specification.

[0024] Example 1, as Figure 1-2 As shown, this utility model provides a device for adjusting flue gas temperature. This device, without adding an air cooler or water cooling system, meets the flue gas temperature requirements of a power plant's SCR denitrification unit through air distribution technology. The device includes a main flue gas pipe, with the SCR denitrification unit installed at the flue gas outlet. A gas distribution branch pipe is installed on the main flue gas pipe, including a gas delivery pipe. An angled gas delivery connecting pipe is installed at one end of the gas delivery pipe near the main flue gas pipe, and a blower is installed at the other end. An electric butterfly valve is installed on the gas delivery pipe, and a temperature sensor is installed on the main flue gas pipe near the SCR unit.

[0025] The angle between the gas delivery connecting pipe and the exhaust main pipe is 45°.

[0026] The device also includes a denitrification control box, which is electrically connected to an electric butterfly valve, a blower, and a temperature sensor.

[0027] An air filter is installed at the air inlet of the blower.

[0028] Main exhaust pipe 1: Used to collect exhaust gases from various gas-fired internal combustion engines.

[0029] Air distribution branch pipe 2: connects the blower and the main exhaust pipe, and is used to deliver cold air to the main exhaust pipe.

[0030] Electric butterfly valve 3: Installed on the gas distribution branch pipe, used to control the entry of cold air.

[0031] Blower 4: Used for forced air distribution, delivering cold air to the main exhaust pipe.

[0032] Denitrification control box 5: Used to control the operation of electric butterfly valves and blowers to regulate the exhaust gas temperature.

[0033] Temperature sensor 6: Installed on the main exhaust pipe before the SCR denitrification unit, used to monitor the exhaust temperature in real time.

[0034] Air filter 7: Installed at the air inlet of the blower to filter the incoming air and prevent dust and other impurities from entering the system.

[0035] The working principle of this device is as follows:

[0036] By using blower 4 to force air distribution, cold air is delivered into the main exhaust pipe, thereby reducing the exhaust temperature.

[0037] When the gas distribution branch pipe 2 is connected to the main exhaust pipe 1, it is at a 45-degree angle along the direction of flue gas flow, which helps the flue gas flow.

[0038] A temperature sensor 6 is installed on the main exhaust pipe 1 before the SCR denitrification unit to monitor the exhaust temperature in real time and ensure that it is within the working temperature range of the catalyst.

[0039] The denitrification control box 5 adopts a closed-loop control strategy. Feedback from the downstream temperature sensor 6 controls the opening and closing of the electric butterfly valve 3 in real time, regulates the speed of the blower motor, and adjusts the amount of cold air entering the exhaust manifold in real time, thereby adjusting the exhaust temperature. Closed-loop control ensures that the exhaust temperature meets the catalyst's operating requirements under different operating conditions.

[0040] During gas engine startup and low-load operation, the flue gas temperature may be lower than the catalyst's optimal temperature. The denitrification control box 5 controls the electric butterfly valve 3 to close, preventing cold air from entering the main exhaust pipe. The closing of the electric butterfly valve 3 also blocks the high-temperature flue gas, preventing damage to the blower.

[0041] Air filter 8 is made of stainless steel wire mesh and is installed at the air inlet of the blower to prevent dust, debris and other impurities from entering the exhaust duct.

[0042] By taking the above measures, the exhaust temperature of the gas internal combustion engine can be effectively regulated to ensure that it is within the suitable operating temperature range of the catalyst, thereby improving the denitrification efficiency and extending the service life of the catalyst.

[0043] Temperature monitoring: By installing a temperature sensor 6 on the exhaust manifold before the SCR denitrification unit, the exhaust temperature is monitored in real time to ensure that it is within the working temperature range of the catalyst (260℃-420℃).

[0044] Closed-loop control: The denitrification control box 5 adopts a closed-loop control strategy. Based on the temperature data fed back by the temperature sensor 6, it controls the opening and closing of the electric butterfly valve 3 and the speed of the blower motor 4 in real time, thereby adjusting the amount of cold air entering the exhaust manifold to achieve the purpose of adjusting the exhaust temperature.

[0045] Low-load operation protection: During startup and low-load operation of the gas internal combustion engine, the flue gas temperature may be lower than the suitable temperature of the catalyst. At this time, the electric butterfly valve 3 closes, preventing cold air from entering the exhaust manifold and blocking the high-temperature flue gas to avoid damage to the blower.

[0046] Regular maintenance: Regularly inspect and maintain the air filter 7 to ensure it is clean and prevent dust, debris and other impurities from entering the system and affecting the air distribution effect.

[0047] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the protection scope of the technical solution of the present utility model.

Claims

1. A device for adjusting the exhaust gas temperature, comprising an exhaust gas main pipe, characterized in that, An SCR denitrification device is installed at the exhaust outlet of the main exhaust pipe. A gas distribution branch pipe is installed on the main exhaust pipe. The gas distribution branch pipe includes a gas delivery pipe. An angled gas delivery connecting pipe is installed at one end of the gas delivery pipe near the main exhaust pipe, and a blower is installed at the other end. An electric butterfly valve is installed on the gas delivery pipe. A temperature sensor is installed on the main exhaust pipe near the SCR device.

2. The device for adjusting the exhaust gas temperature according to claim 1, characterized in that, The angle between the included gas delivery connecting pipe and the exhaust main pipe is 45°.

3. The device for adjusting the exhaust gas temperature according to claim 1, characterized in that, It also includes a denitrification control box, which is electrically connected to an electric butterfly valve, a blower, and a temperature sensor.

4. The device for adjusting the exhaust gas temperature according to claim 1, characterized in that, An air filter is installed at the air inlet of the blower.

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