Tail gas treatment device for silicon carbide smelting furnace
By combining air coolers, hexagonal electrostatic precipitators, and micro-dust filters, the problems of unstable gas volume, temperature, and pressure fluctuations in the tail gas treatment of silicon carbide smelting furnaces were solved, achieving efficient purification and stable gas delivery of the tail gas, and meeting the stringent requirements of the gas consumption points.
Patent Information
- Application Number
- CN202422870801.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-25
- Publication Date
- 2025-10-28
- Estimated Expiration
- 2034-11-25
AI Technical Summary
The tail gas from silicon carbide smelting furnaces suffers from problems such as unstable gas volume, temperature and pressure fluctuations, and high tar content during treatment. This results in the tail gas failing to meet the stringent requirements of the gas consumption points, and existing equipment is prone to clogging, making it unusable.
The system employs a combination of air coolers, hexagonal electrostatic precipitators, wet gas holders, and micro-dust filters. Through multi-stage filtration and buffering, it achieves stable cooling and purification of exhaust gas, ensuring stable pressure, small particle size of impurities, low tar content, and appropriate moisture content at the point of use.
It achieves stable exhaust gas delivery with a pressure change rate of less than 1 kPa/min, impurity particle size of less than 5 μm, tar content of less than 5 mg/Nm3, moisture content of no more than 40 g/Nm3, and temperature within the range of 10–50℃. The equipment operates stably, is easy to maintain, and has low cost.
Smart Images
Figure CN223484869U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of silicon carbide smelting technology, specifically to a silicon carbide smelting furnace tail gas treatment device. Background Technology
[0002] The exhaust gas recovered from the closed-loop silicon carbide negative pressure smelting furnace is cooled and dust-removed by the furnace's supporting purification equipment. The exhaust gas pressure is approximately 4 kPa and the particulate matter content is approximately 200 mg / Nm³. 3 Tar content approximately 50 mg / Nm 3 The gas temperature is greater than 120℃.
[0003] During the smelting process in the silicon carbide furnace, the flow rate, composition, pressure, and temperature of the closed-loop collected tail gas fluctuate, the gas volume is unstable, and the particulate matter and tar content in the treated tail gas also change, making the gas pipeline prone to blockage.
[0004] The furnace gas volume fluctuates and is unstable, the temperature fluctuates unstably, and the furnace gas contains trace amounts of tar. Specific characteristics are as follows: 1. Unstable temperature fluctuations: 120-200℃; 2. Unstable pressure fluctuations: 600-8000Pa; 3. Tar content in the furnace gas >50 mg / m³. 3 4. The particulate matter content of the purified coal gas is >200 mg / L.
[0005] For gas-consuming points that have strict and stable requirements for the cleanliness, pressure, temperature, composition, and moisture content of the gas source, if the above-mentioned problems are not resolved, the collected exhaust gas will not meet the needs of the gas-consuming point, and the exhaust gas cannot be effectively and reliably utilized. Utility Model Content
[0006] To achieve the above objectives, the present invention provides the following technical solutions:
[0007] A tail gas treatment device for silicon carbide smelting furnace includes a gas consumption point and a user gas source. The user gas source is connected to an air cooler. The other end of the air cooler is connected to an electric butterfly valve of a hexagonal electrostatic precipitator. Both ends of the hexagonal electrostatic precipitator are equipped with electric butterfly valves and electric blind valves. One electric butterfly valve is connected in parallel with the electric butterfly valves at both ends. The electric butterfly valve at the other end is connected to a pneumatic quick-cut valve. An electric vent valve is connected to a gate valve. The gate valve is connected to the pneumatic quick-cut valve. The pneumatic quick-cut valve is connected to a wet gas holder. An electric blind valve and an electric butterfly valve are connected sequentially between the pneumatic quick-cut valve and the wet gas holder.
[0008] The wet gas holder is connected in sequence to the gas consumption point by one electric butterfly valve, one electric blind valve, one electric butterfly valve, two electric butterfly valves, two electric blind valves, two compressors, two manual gate valves, two electric balancing valves, two manual gate valves, two micro-dust filters, two electric blind valves, and two electric butterfly valves. The two electric butterfly valves, two electric blind valves, two compressors, two manual gate valves, two electric balancing valves, two manual gate valves, two micro-dust filters, two electric blind valves, and two electric butterfly valves are connected in parallel. The two compressors are connected in parallel with the two manual gate valves, two electric balancing valves, and two manual gate valves.
[0009] Preferred configuration: The air cooler is equipped with two upper pipe boxes, and a connecting pipe is installed between the two upper pipe boxes. One upper pipe box is equipped with a gas inlet, and the other upper pipe box is equipped with a gas outlet. The upper pipe boxes are connected to several air-cooling pipes. An ash hopper is installed below the air-cooling pipes, and an ash discharge pipe is installed below the ash hopper. The two sides of the ash hopper are fixedly connected to the support.
[0010] Preferred: The hexagonal electrostatic precipitator is a high-voltage hexagonal electrostatic precipitator. An insulator box is installed at the upper end of the hexagonal electrostatic precipitator. The insulator box is connected to the gas outlet. A corona electrode is installed below the insulator box. The corona electrode is connected to the honeycomb body. A counterweight is installed below the honeycomb body. An explosion-proof valve and a gas inlet are installed below the cylinder.
[0011] Preferably, a ladder is provided on one side of the wet gas holder and an upper guide wheel is provided on the other side. A water tank is provided below the wet gas holder and is connected to the gas inlet and gas outlet. A tower is provided above the water tank and a bell is provided above the tower. An outer guide rail is provided between the bell and the ladder.
[0012] Preferably, the micro-dust filter has a manhole at the top, a gas inlet and a gas outlet on the outer shell, a filter element inside the outer shell, and the outer shell is fixedly connected to the support legs.
[0013] Compared with the prior art, the present invention has the following beneficial effects:
[0014] I. Target indicators achievable after fine treatment of tail gas from silicon carbide smelting furnace: 1. The gas holder pressure remains stable at a constant pressure, and the pressure change rate at the gas consumption point is ≤1 kPa / min; 2. Impurity particle size <5 μm, and impurity content ≤30 mg / Nm³. 3 3. Tar content in fuel gas ≤ 5 mg / Nm³ 3 4. Moisture content not exceeding 40g / Nm 3 5. Temperature: 10–50℃.
[0015] Second, the exhaust gas is cooled indirectly, which does not produce water pollution.
[0016] Third, the configured equipment is stable, safe and reliable in operation, easy to maintain, and has low operating and processing costs. Attached Figure Description
[0017] Figure 1 This is a simplified diagram of the present utility model;
[0018] Figure 2 for Figure 1 Structural diagram of the intermediate cooler (110);
[0019] Figure 3 for Figure 1 Structural diagram of the hexagonal electrostatic precipitator (120);
[0020] Figure 4 for Figure 1 Structural diagram of medium-humidity gas holder (130);
[0021] Figure 5 for Figure 1 Structural diagram of the fine dust filter (150).
[0022] Figure reference numerals: 1. Electric vent valve; 2. Gate valve; 3. Pneumatic quick-cut valve; 4. Electric blind valve; 5. Electric butterfly valve; 6. Electric balancing valve; 7. Manual gate valve; 8. Gas inlet; 9. Gas outlet; 110. Air cooler; 111. Connecting pipe; 113. Upper pipe box; 114. Air-cooled pipe; 115. Ash hopper; 116. Support; 117. Ash discharge pipe; 120. Hexagonal electrostatic precipitator; 121. Insulator box; 122. Explosion-proof valve; 123. Cylinder; 124. Counterweight; 125. Honeycomb structure; 126. Corona electrode; 130. Wet gas holder; 131. Upper guide wheel; 133. Water tank; 134. Tower; 135. Bell jar; 136. External guide rail; 137. Ladder; 140. Compressor; 150. Micro-dust filter; 151. Manhole; 153. Support leg; 155. Outer shell; 156. Filter element; 160. Gas consumption point; 170. User gas source. Detailed Implementation
[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0024] like Figure 1-2As shown, the tail gas recovered from the closed silicon carbide smelting furnace is initially treated and then sent to the main gas pipe. It is then fed into an air cooler to cool the tail gas inside the pipe, reducing the temperature to below 70°C. Large dust particles and condensate in the tail gas are collected through the air-cooling pipe. The tail gas then enters a high-pressure hexagonal electrostatic precipitator to remove most of the tar (over 90%), dust, and moisture from the gas. Next, the tail gas enters a gas holder, which serves to buffer, stabilize, and mix the gas. The tail gas is then sent from the gas holder outlet to the compressor inlet. The compressor model is selected based on the pressure requirements of the gas consumption point. After being pressurized by the compressor, the tail gas is sent to a fine dust filter for further purification, where fine dust (particle size less than 5μm after treatment) and water mist are collected. The treated tail gas is then delivered to the gas consumption point.
[0025] like Figure 3 As shown, the main function of a high-voltage hexagonal electrostatic precipitator is to remove tar and dust from gases. In physics, it is known that electrons or charged particles will move in a directed manner under the influence of an electric field; the high-voltage hexagonal electrostatic precipitator works based on this principle. When gas containing tar and other solid particles enters the high-voltage hexagonal electrostatic precipitator, the device has positive and negative electrodes. The DC voltage supplied is 40-60kV. Under the influence of this high-voltage electric field, the gas around the corona electrode is ionized. This ionization produces electrons and positively charged ions. During gas flow, dust particles are attracted by these electrons and positively charged ions, forming charged dust particles and positively charged dust particles. Under the influence of the high-voltage electric field, these charged particles move towards their respective poles: negatively charged dust particles move towards the settling pole, and positively charged dust particles move towards the corona electrode. During this movement, they continuously absorb other dust particles, forming larger particles that eventually reach the settling pole and adhere to the tube wall. As more dust adheres, its own weight causes it to flow down the settling pole wall, achieving the purpose of dust removal. High-voltage hexagonal electrostatic precipitators offer the best cost-performance ratio, featuring no blind spots, a large adsorption area, and high efficiency. They also offer advantages such as large gas volume handling, slow gas flow rate, multiple corona lines, large adsorption area, small equipment weight, and low price. It also adopts a constant current high voltage DC power supply, which has advantages such as large corona power, good energy saving effect, high power factor and automated operation.
[0026] like Figure 4 As shown, gas holders can be selected from wet gas holders or dry rubber membrane gas holders, depending on the geographical location of the gas consumption point and the user's needs. Gas holders play the following three main roles in exhaust gas transmission systems:
[0027] Buffer: The gas produced in the smelting furnace is very unstable, and the gas volume fluctuates depending on the furnace conditions. In order to resolve the contradiction between the frequent changes in gas production and consumption, a gas storage tank with a certain capacity is set up. This tank not only regulates the gas volume but also ensures a stable gas supply pressure at the gas consumption points, thus making full use of the gas.
[0028] Pressure stabilization: If the purified coal gas from the submerged arc furnace is directly sent to users, the operation of the combustion equipment will be extremely unstable. The recovered coal gas is first sent to the gas holder through pipelines. Due to the special characteristics of the gas holder, it has a certain volume and can output a stable pressure. This characteristic perfectly meets the gas consumption requirements of downstream gas users, and the operation of the combustion equipment is also easier to control.
[0029] Mixing: The gas produced during production has a complex composition, and the gas produced at different times varies, affecting its quality. To ensure users receive gas of relatively stable quality, a mixing device (i.e., blending) is necessary, and a gas storage tank can serve this purpose.
[0030] like Figure 5 As shown, the micro-dust fine filter is equipped with a filter element with a pore size controlled at 5μm. The filter element material has a certain degree of waterproof performance and can capture micro-dust and water mist in the gas at the same time.
[0031] In the description of this utility model, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.
[0032] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0033] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A tail gas treatment device for a silicon carbide smelting furnace, comprising a gas consumption point (160) and a user gas source (170), wherein the user gas source (170) is connected to an air cooler (110), characterized in that: The other end of the air cooler (110) is connected to the electric butterfly valve (5) of the hexagonal electrostatic precipitator (120). Both ends of the hexagonal electrostatic precipitator (120) are equipped with electric butterfly valves (5) and electric blind valves (4). One electric butterfly valve (5) is connected in parallel with the electric butterfly valves (5) at both ends. The electric butterfly valve (5) at the other end is connected to the pneumatic quick-cut valve (3). The electric vent valve (1) is connected to the gate valve (2). The gate valve (2) is connected to the pneumatic quick-cut valve (3). The pneumatic quick-cut valve (3) is connected to the wet gas holder (130). The pneumatic quick-cut valve (3) and the wet gas holder (130) are connected in sequence with the electric blind valve (4) and the electric butterfly valve (5). A wet gas holder (130) and a gas consumption point (160) are connected in sequence to an electric butterfly valve (5), an electric blind valve (4), an electric butterfly valve (5), two electric butterfly valves (5), two electric blind valves (4), two compressors (140), two manual gate valves (7), two electric balancing valves (6), two micro-dust filters (150), two electric blind valves (4), and two electric butterfly valves (5). The two electric butterfly valves (5), two electric blind valves (4), two compressors (140), two manual gate valves (7), two electric balancing valves (6), two micro-dust filters (150), two electric blind valves (4), and two electric butterfly valves (5) are connected in parallel. The two compressors (140) are connected in parallel with the two manual gate valves (7), two electric balancing valves (6), and two manual gate valves (7).
2. The silicon carbide smelting furnace tail gas treatment device according to claim 1, characterized in that: Two upper pipe boxes (113) are installed on the air cooler (110), and a connecting pipe (111) is installed between the two upper pipe boxes (113). One upper pipe box (113) is equipped with a gas inlet (8), and the other upper pipe box (113) is equipped with a gas outlet (9). The upper pipe box (113) is connected to several air cooling pipes (114). A ash hopper (115) is installed below the air cooling pipes (114), and an ash discharge pipe (117) is installed below the ash hopper (115). The two sides of the ash hopper (115) are fixedly connected to the support (116).
3. The silicon carbide smelting furnace tail gas treatment device according to claim 1, characterized in that: An insulator box (121) is installed at the upper end of the hexagonal electrostatic precipitator (120). The insulator box (121) is connected to the gas outlet (9). A corona electrode (126) is installed below the insulator box (121). The corona electrode (126) is connected to the honeycomb body (125). A counterweight (124) is installed below the honeycomb body (125). An explosion-proof valve (122) and a gas inlet (8) are installed below the cylinder (123).
4. The silicon carbide smelting furnace tail gas treatment device according to claim 1, characterized in that: A ladder (137) is provided on one side of the wet gas holder (130), and an upper guide wheel (131) is provided on the other side. A water tank (133) is provided below the wet gas holder (130). The water tank (133) is connected to the gas inlet (8) and the gas outlet (9). A tower (134) is provided above the water tank (133). A bell jar (135) is provided above the tower (134). An outer guide rail (136) is provided between the bell jar (135) and the ladder (137).
5. The silicon carbide smelting furnace tail gas treatment device according to claim 1, characterized in that: The micro-dust filter (150) is provided with a manhole (151) at the upper end, and a gas inlet (8) and a gas outlet (9) are provided on the outer shell (155). A filter element (156) is provided inside the outer shell (155), and the outer shell (155) is fixedly connected to the support leg (153).