Air quenching flue gas purification system and purification method

Abstract

The invention relates to the technical field of flue gas purification devices, in particular to an air-quenching flue gas purification system and method, an air-quenching flue gas outlet is connected with a flue gas inlet of a flue gas cleaning chamber, and a discharge port of the flue gas cleaning chamber is connected with a feed port of a gas-liquid separator; a flue gas outlet of the gas-liquid separator is connected with the input end of the fan, and the output end of the fan is connected with the chimney; a liquid outlet of the gas-liquid separator is connected with a liquid inlet of the liquid collecting box, a liquid outlet of the liquid collecting box is connected with a liquid inlet of the reservoir, and a steam outlet of the liquid collecting box is connected with the gas-liquid separator; a liquid outlet of the reservoir is connected with an input end of the solution pump, an output end of the solution pump is connected with a circulating liquid pipeline, the first branch is connected with the liquid collecting box, the second branch is connected with the flue gas cleaning chamber, and the third branch is connected with the air quenching slag chamber. According to the invention, the capturing efficiency of dust and gas pollutants in flue gas is improved.

Description

Technical Field

[0001] This invention relates to the field of flue gas purification devices, specifically to an air-quenched flue gas purification system and purification method. Background Technology

[0002] In metallurgical production, air quenching is a common and important processing method. During air quenching, high-temperature molten slag is rapidly cooled and fragmented under the impact of high-speed airflow, forming granular materials with specific particle size and properties. However, air quenching operations generate a large amount of flue gas containing pollutants such as dust and harmful gases. If directly emitted into the atmosphere, it will cause serious pollution to the surrounding environment, endanger human health, and violate increasingly stringent environmental regulations.

[0003] Currently, common flue gas purification methods for air quenching flue gas include dry dust removal and wet dust removal. Dry dust removal mainly utilizes principles such as filtration and electrostatic adsorption to remove dust from flue gas, but its effectiveness in removing some fine particles and gaseous pollutants is limited, and its equipment investment and operating costs are high, as is its maintenance and management. Wet dust removal, on the other hand, involves contacting water or other solutions with the flue gas to dissolve or capture pollutants, resulting in higher dust removal efficiency, especially for fine particles and some gaseous pollutants.

[0004] While existing wet flue gas purification systems can purify air-quenched flue gas to some extent, they still have many shortcomings. For example, in some systems, the contact between the cleaning water and the flue gas is insufficient during the cleaning process, resulting in unsatisfactory purification effects and an inability to effectively remove various pollutants from the flue gas. The gas-liquid separation process is not perfect, leaving the cleaned flue gas with a large amount of moisture, which not only affects the subsequent emission of flue gas but may also cause corrosion to equipment such as fans. In terms of the recycling of cleaning water, there is a lack of effective treatment and distribution mechanisms, leading to serious waste of water resources. At the same time, the quality of the recycled slurry water is unstable, which can easily affect the operation and purification efficiency of the entire purification system. Summary of the Invention

[0005] To address the problems of poor purification effect and poor recycling effect of cleaning water in the existing technology, the present invention provides a flue gas purification system and purification method for air quenching.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A flue gas purification system for air quenching includes an air quenching slag chamber, a flue gas cleaning chamber, a gas-liquid separator, a liquid collection tank, a water storage tank, a solution pump, a blower, and a chimney. The air quenching slag chamber has an air quenching flue gas outlet at its top, the flue gas cleaning chamber has a flue gas inlet at its top and a discharge outlet at its bottom, the gas-liquid separator has a flue gas outlet at its top, a feed inlet in its middle, and a liquid outlet at its bottom. The air quenching flue gas outlet at the top of the air quenching slag chamber is connected to the flue gas inlet of the flue gas cleaning chamber, and the discharge outlet of the flue gas cleaning chamber is connected to the feed inlet of the gas-liquid separator. The flue gas outlet of the gas-liquid separator is connected to... The fan is connected to its input end, and its output end is connected to the chimney. The liquid collection tank has a liquid inlet, a liquid outlet, and a steam outlet. The liquid outlet of the gas-liquid separator is connected to the liquid inlet of the liquid collection tank, the liquid outlet of the liquid collection tank is connected to the liquid inlet of the water storage tank, and the steam outlet of the liquid collection tank is connected to the gas-liquid separator. The liquid outlet of the water storage tank is connected to the input end of the solution pump, and the output end of the solution pump is connected to the circulating liquid pipeline. The circulating liquid pipeline has a first branch, a second branch, and a third branch. The first branch is connected to the liquid collection tank, the second branch is connected to the flue gas cleaning chamber, and the third branch is connected to the air-quenched slag chamber.

[0008] Furthermore, the flue gas cleaning chamber is equipped with multiple spray nozzles, and the spraying direction of the nozzles is opposite to the flow direction of the flue gas in the flue gas cleaning chamber; the water supply pipe of the nozzles is connected to the second branch.

[0009] Furthermore, the gas-liquid separator is equipped with a demister, which is located above the feed inlet of the gas-liquid separator and above the connection between the steam outlet of the liquid collection tank and the gas-liquid separator.

[0010] Furthermore, the water storage tank is equipped with a mudguard, the height of which is lower than the depth of the water storage tank; the mudguard divides the water storage tank into a settling zone and a clear water zone, the inlet of the water storage tank is located in the settling zone, and the outlet of the water storage tank is located in the clear water zone.

[0011] This invention also includes the following technical solutions:

[0012] A method for purifying the flue gas from the aforementioned flue gas purification system includes the following steps:

[0013] S1. The quenching flue gas generated in the quenching slag chamber enters the flue gas cleaning chamber through the quenching flue gas outlet at the top of the quenching slag chamber for flue gas cleaning.

[0014] S2. The flue gas and slurry cleaned in the flue gas cleaning chamber enter the gas-liquid separator through the discharge port of the flue gas cleaning chamber. The slurry enters the water collection tank through the liquid outlet at the bottom of the gas-liquid separator. The cleaned flue gas is discharged through the chimney under the action of the fan.

[0015] S3. The slurry entering the water collection tank will generate water vapor due to its high temperature. The water vapor enters the gas-liquid separator through the steam outlet on the water collection tank and is separated into gas and liquid again with the cleaned flue gas.

[0016] S4. The slurry is discharged into the storage tank through the outlet in the collection tank for sedimentation and separation. The supernatant after separation is pumped to the air quenching slag chamber, the flue gas cleaning chamber and the collection tank respectively.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] This invention provides a flue gas purification system and method for air quenching. The flue gas cleaning chamber uses nozzles with the opposite flow direction to the air quenching flue gas to spray water in the reverse direction, so that the flue gas and cleaning water can fully contact each other, which improves the capture efficiency of dust and gaseous pollutants in the flue gas, enabling the emitted flue gas to meet higher environmental protection standards and reducing pollution to the atmospheric environment. The cleaned flue gas and slurry enter a gas-liquid separator, where the moisture carried by the flue gas is effectively separated, avoiding corrosion of subsequent equipment such as fans and chimneys caused by excessive moisture content in the flue gas. The separated slurry enters the collection tank, while the flue gas is discharged from the top flue gas outlet. The slurry in the collection tank is discharged into the storage tank for sedimentation and separation. The supernatant after separation is pumped to the air quenching slag chamber, the flue gas cleaning chamber and the collection tank respectively, realizing the recycling of water resources. This not only reduces water consumption and lowers the company's water costs, but also reduces wastewater discharge. The dust settled in the storage tank is cleaned and recycled regularly, realizing the effective utilization of dust in the air quenching process, reducing pollution while maximizing the company's economic benefits. Attached Figure Description

[0019] The embodiments of the present invention will be further described below with reference to the accompanying drawings, wherein:

[0020] Figure 1 The process flow diagram of the air quenching flue gas purification system is shown;

[0021] Figure 2 A schematic diagram of an embodiment of the air-quenched flue gas purification system is shown (circulating liquid pipeline is not shown);

[0022] Figure 3 A schematic diagram of an embodiment of the flue gas cleaning chamber is shown;

[0023] Figure 4 A schematic diagram of an embodiment of the gas-liquid separator is shown;

[0024] Figure 5 A schematic diagram of an embodiment of the water storage tank is shown;

[0025] Attached diagram labels: 1-Air quenching slag chamber, 2-Flue gas cleaning chamber, 2-1-Nozzle, 3-Gas-liquid separator, 3-1-Demister, 4-Collection tank, 5-Water storage tank, 5-1-Mud baffle, 5-2-Settling zone, 5-3-Clear water zone, 5-4-Inlet pipe, 5-5-Inlet valve, 5-6-Outlet pipe, 5-7-Outlet valve, 5-8-Outlet pipe pressure gauge, 5-9-First buffer section, 5-10-Second buffer section, 5-11-Circulating liquid pipeline pressure gauge, 5-12-Circulating liquid pipeline regulating valve, 6-Solution pump, 7-Fan, 8-Chimney. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0027] Reference Appendix Figure 1-2 A flue gas purification system for air quenching includes an air quenching slag chamber 1, a flue gas cleaning chamber 2, a gas-liquid separator 3, a liquid collection tank 4, a water storage tank 5, a solution pump 6, a blower 7, and a chimney 8. The air quenching slag chamber 1 has an air quenching flue gas outlet at its top, the flue gas cleaning chamber 2 has a flue gas inlet at its top and a discharge outlet at its bottom, the gas-liquid separator 3 has a flue gas outlet at its top, a feed inlet in its middle, and a liquid outlet at its bottom. The air quenching flue gas outlet at the top of the air quenching slag chamber 1 is connected to the flue gas inlet of the flue gas cleaning chamber 2, and the discharge outlet of the flue gas cleaning chamber 2 is connected to the feed inlet of the gas-liquid separator 3. The flue gas outlet of the liquid separator 3 is connected to the input end of the blower 7, and the output end of the blower 7 is connected to the chimney 8; the liquid collection tank 4 is provided with a liquid inlet, a liquid outlet and a steam outlet, the liquid outlet of the gas-liquid separator 3 is connected to the liquid inlet of the liquid collection tank 4, the liquid outlet of the liquid collection tank 4 is connected to the liquid inlet of the water storage tank 5, and the steam outlet of the liquid collection tank 4 is connected to the gas-liquid separator 3; the liquid outlet of the water storage tank 5 is connected to the input end of the solution pump 6, and the output end of the solution pump 6 is connected to the circulating liquid pipeline. The circulating liquid pipeline is provided with a first branch, a second branch and a third branch. The first branch is connected to the liquid collection tank 4, the second branch is connected to the flue gas cleaning chamber 2, and the third branch is connected to the air quenching slag chamber 1.

[0028] Reference Appendix Figure 3 In one embodiment of the present invention, the flue gas cleaning chamber 2 is provided with multi-layer nozzles 2-1, the spraying direction of the nozzles 2-1 is opposite to the flow direction of the flue gas in the flue gas cleaning chamber 2; the water supply pipe of the nozzles 2-1 is connected to the second branch.

[0029] Reference Appendix Figure 4In one embodiment of the present invention, a demister 3-1 is provided inside the gas-liquid separator 3. The demister 3-1 is located above the feed inlet of the gas-liquid separator 3 and above the connection between the steam outlet of the liquid collection tank 4 and the gas-liquid separator 3. The slurry generated by the flue gas cleaning chamber 2 and the cleaned high-temperature flue gas enter the gas-liquid separator 3. The slurry falls to the bottom of the gas-liquid separator 3 under its own gravity and eventually flows into the liquid collection tank 4. The high-temperature flue gas moves upward under the action of the fan 7. The water vapor in the high-temperature flue gas forms droplets on the surface of the demister 3-1 and eventually falls to the bottom of the gas-liquid separator 3, reducing the water content of the high-temperature flue gas.

[0030] Reference Appendix Figure 5 In one embodiment of the present invention, a mudguard 5-1 is provided inside the water storage tank 5, the height of which is less than the depth of the water storage tank 5; the mudguard 5-1 divides the water storage tank 5 into a settling zone 5-2 and a clear water zone 5-3; the inlet of the water storage tank 5 is located in the settling zone 5-2, and the outlet of the water storage tank 5 is located in the clear water zone 5-3. A first end of an inlet pipe 5-4 is provided in the settling zone 5-2, and an inlet valve 5-5 is provided on the inlet pipe 5-4; an outlet pipe 5-6 is provided in the clear water zone 5-3, and an outlet valve 5-7, an outlet pipe pressure gauge 5-8, and a first buffer section 5-9 are provided on the outlet pipe 5-6; the second end of the outlet pipe 5-6 is connected to the input end of a solution pump 6, and the output end of the solution pump 6 is connected to a circulating liquid pipeline, which is equipped with a second buffer section 5-10, a circulating liquid pipeline pressure gauge 5-11, and a circulating liquid pipeline regulating valve 5-12; a first branch is provided on the circulating liquid pipeline. The system consists of three branches: the first branch connects to the collection tank 4, which agitates the slurry at the outlet of the collection tank 4 to prevent solid particles in the slurry from settling at the outlet of the collection tank 4, thus preventing blockage and affecting the operation of the entire purification system; the second branch connects to the flue gas cleaning chamber 2 to achieve slurry recycling; and the third branch connects to the air-quenched slag chamber 1, where high-temperature molten slag is dispersed into granular form by high-pressure air. The third branch provides spray water to the air-quenched slag chamber 1 to cool the granular molten slag and simultaneously remove dust from the flue gas.

[0031] A method for purifying the flue gas from the aforementioned flue gas purification system includes the following steps:

[0032] S1. The quenching flue gas generated in the air quenching slag chamber 1 enters the flue gas cleaning chamber 2 through the air quenching flue gas outlet at the top of the air quenching slag chamber 1 for flue gas cleaning.

[0033] S2. The flue gas and slurry cleaned in the flue gas cleaning chamber 2 enter the gas-liquid separator 3 through the discharge port of the flue gas cleaning chamber 2. The slurry enters the water collection tank 4 through the liquid outlet at the bottom of the gas-liquid separator 3. The cleaned flue gas is discharged through the chimney 8 under the action of the fan 7.

[0034] S3. The slurry entering the water collection tank 4 will generate water vapor due to its high temperature. The water vapor enters the gas-liquid separator 3 through the steam outlet on the water collection tank 4 and is separated from the cleaned flue gas again.

[0035] S4. The slurry is discharged into the water storage tank 5 through the outlet in the water collection tank 4 for sedimentation and separation. The supernatant after separation is transported to the air quenching slag chamber 1, the flue gas cleaning chamber 2 and the water collection tank 4 respectively by the solution pump 6.

[0036] This invention provides a flue gas purification system and method for air quenching. The flue gas cleaning chamber uses nozzles with the opposite flow direction to the air quenching flue gas to spray water in the reverse direction, so that the flue gas and cleaning water can fully contact each other, which improves the capture efficiency of dust and gaseous pollutants in the flue gas, enabling the emitted flue gas to meet higher environmental protection standards and reducing pollution to the atmospheric environment. The cleaned flue gas and slurry enter a gas-liquid separator, where the moisture carried by the flue gas is effectively separated, avoiding corrosion of subsequent equipment such as fans and chimneys caused by excessive moisture content in the flue gas. The separated slurry enters the collection tank, while the flue gas is discharged from the top flue gas outlet. The slurry in the collection tank is discharged into the storage tank for sedimentation and separation. The supernatant after separation is pumped to the air quenching slag chamber, the flue gas cleaning chamber and the collection tank respectively, realizing the recycling of water resources. This not only reduces water consumption and lowers the company's water costs, but also reduces wastewater discharge. The dust settled in the storage tank is cleaned and recycled regularly, realizing the effective utilization of dust in the air quenching process, reducing pollution while maximizing the company's economic benefits.

[0037] The foregoing descriptions have outlined some exemplary embodiments of the present invention. It is understood that these embodiments are merely illustrative and do not constitute a limitation on the scope of protection of the present invention. Features in these embodiments can be rearranged in suitable ways, and the resulting solutions remain within the scope of protection claimed by the present invention. All other embodiments obtained by those skilled in the art based on the foregoing embodiments without inventive effort, i.e., all modifications, equivalent substitutions, and improvements made within the spirit and principles of this application, fall within the scope of protection claimed by the present invention.

Claims

1. A flue gas purification system for air quenching, characterized in that, The system includes an air-quenching slag chamber (1), a flue gas cleaning chamber (2), a gas-liquid separator (3), a liquid collection tank (4), a water storage tank (5), a solution pump (6), a blower (7), and a chimney (8). The air-quenching slag chamber (1) has an air-quenching flue gas outlet at its top, the flue gas cleaning chamber (2) has a flue gas inlet at its top and a discharge outlet at its bottom, the gas-liquid separator (3) has a flue gas outlet at its top, a feed inlet in its middle, and a liquid outlet at its bottom. The air-quenching flue gas outlet at the top of the air-quenching slag chamber (1) is connected to the flue gas inlet of the flue gas cleaning chamber (2), and the discharge outlet of the flue gas cleaning chamber (2) is connected to the feed inlet of the gas-liquid separator (3). The flue gas outlet of the gas-liquid separator (3) is connected to... The input end of the blower (7) and the output end of the blower (7) are connected to the chimney (8); the liquid collection tank (4) is provided with a liquid inlet, a liquid outlet and a steam outlet, the liquid outlet of the gas-liquid separator (3) is connected to the liquid inlet of the liquid collection tank (4), the liquid outlet of the liquid collection tank (4) is connected to the liquid inlet of the water storage tank (5), and the steam outlet of the liquid collection tank (4) is connected to the gas-liquid separator (3); the liquid outlet of the water storage tank (5) is connected to the input end of the solution pump (6), the output end of the solution pump (6) is connected to the circulating liquid pipeline, the circulating liquid pipeline is provided with a first branch, a second branch and a third branch, the first branch is connected to the liquid collection tank (4), the second branch is connected to the flue gas cleaning chamber (2), and the third branch is connected to the air quenching slag chamber (1).

2. The air-quenching flue gas purification system according to claim 1, characterized in that, The flue gas cleaning chamber (2) is equipped with multiple spray nozzles (2-1), and the spraying direction of the spray nozzles (2-1) is opposite to the flow direction of the flue gas in the flue gas cleaning chamber (2); the water supply pipeline of the spray nozzles (2-1) is connected to the second branch.

3. The air-quenching flue gas purification system according to claim 1, characterized in that, The gas-liquid separator (3) is equipped with a demister (3-1), which is located above the feed inlet of the gas-liquid separator (3) and above the connection between the steam outlet of the liquid collection tank (4) and the gas-liquid separator (3).

4. The air-quenching flue gas purification system according to claim 1, characterized in that, The water storage tank (5) is equipped with a mudguard (5-1), the height of which is lower than the depth of the water storage tank (5); the mudguard (5-1) divides the water storage tank (5) into a settling zone (5-2) and a clear water zone (5-3); the liquid inlet of the water storage tank (5) is located in the settling zone (5-2), and the liquid outlet of the water storage tank (5) is located in the clear water zone (5-3).

5. A method for purifying quenching flue gas based on the air quenching flue gas purification system according to any one of claims 1-4, characterized in that, Includes the following steps: S1. The quenching flue gas generated in the air quenching slag chamber (1) enters the flue gas cleaning chamber (2) through the air quenching flue gas outlet at the top of the air quenching slag chamber (1) for flue gas cleaning. S2. The flue gas and slurry cleaned in the flue gas cleaning chamber (2) enter the gas-liquid separator (3) through the outlet of the flue gas cleaning chamber (2). The slurry enters the water collection tank (4) through the liquid outlet at the bottom of the gas-liquid separator (3). The cleaned flue gas is discharged through the chimney (8) under the action of the fan (7). S3. The slurry entering the water collection tank (4) will generate water vapor due to its high temperature. The water vapor enters the gas-liquid separator (3) through the steam outlet on the water collection tank (4) and is separated from the flue gas after cleaning. S4. The slurry is discharged into the storage tank (5) through the outlet in the collection tank (4) for sedimentation and separation. The supernatant after separation is transported to the air quenching slag chamber (1), the flue gas cleaning chamber (2) and the collection tank (4) respectively by the solution pump (6).

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