Desulfurization waste liquid air oxidation device

Abstract

A desulfurization waste liquid air oxidation device comprises a tank body 1, and an air aeration oxidation pipe, a condensate water inner coil pipe 12.1 and a steam inner coil pipe 13 are arranged in the tank body 1. The air aeration oxidation pipe comprises an air main pipe 5, an air branch pipe 5.1 and an aeration pipe 5.2; a blow-down pipe 10 is arranged in the center of the top of the tank body 1, a return pipe 9 is arranged on the left side of the blow-down pipe 10, and a material inlet pipe 8 is arranged on the right side; a material outlet pipe 7 is arranged on the side wall of the bottom of the tank body 1; a thermometer tube 6 is also arranged above the material outlet tube 7; an air main pipe 5 is also arranged between the thermometer tube 6 and the material outlet pipe 7; and an inner inclined bottom 4 is arranged on the inner bottom surface of the tank body 1. The device uses oxygen in air as an oxidizing agent, is mild in reaction, safe and reliable, does not generate harmful waste gas, and eliminates the danger of using sulfuric acid in a conventional process device.

Description

Technical Field

[0001] This utility model relates to the treatment of hazardous waste in the chemical industry and the field of salt extraction from desulfurization waste liquid, specifically a desulfurization waste liquid air oxidation device. Background Technology

[0002] In the wet ammonia desulfurization process of coke oven gas, ammonium thiosulfate and ammonium thiocyanate are generated as byproducts during the regeneration of the circulating desulfurization liquid. The goal of desulfurization waste liquid salt extraction treatment is to extract ammonium thiocyanate. Ammonium thiosulfate is oxidized to ammonium sulfate, which is then separated from ammonium thiocyanate through crystallization separation to obtain ammonium sulfate as a byproduct. The traditional oxidation method for ammonium thiosulfate is the sulfuric acid oxidation method. This method requires the use of concentrated sulfuric acid. This oxidation method requires special equipment and strict protective measures during operation, and it also involves many side reactions and the generation of harmful gases. Summary of the Invention

[0003] To address the issues of numerous side reactions and the generation of harmful gases during the sulfuric acid oxidation process, this invention provides an air oxidation device for desulfurization wastewater. The device includes a tank containing an air aeration oxidation pipe, a condensate inner coil, and a steam inner coil. The air aeration oxidation pipe comprises a main air pipe, branch air pipes, and an aeration pipe. A vent is located at the center of the top of the tank, with a flange at the head and a tail that penetrates the tank and connects to its interior. A material outlet pipe is located on the bottom side wall of the tank, with its head outside the tank and its tail connecting to the interior. A temperature measuring pipe is also located above the material outlet pipe, with its head positioned inside the tank. Externally, the tail end communicates with the interior of the tank. An air inlet is provided between the temperature measuring tube and the material outlet tube, penetrating the tank body. The head of the air inlet is located outside the tank body, and the tail end extends into the tank body and is fixedly connected to the main air pipe. The length of the main air pipe extending into the tank body is approximately equal to the internal diameter of the tank body. Air branch pipes are connected to both sides of the main air pipe. Aeration pipes are vertically installed on the air branch pipes. Aeration holes are provided on the wall of the aeration pipes. The bottom surface inside the tank body has an inner sloping bottom. The inner sloping bottom gradually decreases from one end of the inner wall of the tank body towards the material outlet end, forming a sloping structure. A through hole penetrating the interior of the tank body is provided on the outer wall of the front of the tank body, and a steam inlet is provided at the through hole. One end of the steam inlet is located outside the tank body, and the other end is fixedly connected to an internal steam coil. A through hole penetrating the interior of the tank body is provided on the left side of the steam inlet, and a condensate outlet is provided at the through hole. One end of the condensate outlet is located outside the tank body, and the other end is fixedly connected to an internal condensate coil.

[0004] The aeration holes are evenly arranged in 10 rows along the wall of the aeration pipe, with 7 aeration holes in each row from bottom to top.

[0005] The top of the tank is provided with a top manhole near the ladder, and the bottom of the tank is provided with a bottom manhole near the bottom surface.

[0006] A reserved swirl port A is provided between the manhole at the bottom of the lower end of the outer wall of the tank and the material outlet pipe, and a reserved swirl port B is provided at a position symmetrical to the reserved swirl port A on the outer wall of the tank body 1.

[0007] A stirring port is provided on the lower part of the outer wall of the tank between the level gauge and the reserved swirl port B.

[0008] The tank is equipped with a ladder on the outside, and a guardrail is installed around the ladder.

[0009] The beneficial effects of this invention are: it utilizes air oxidation to desulfurize waste liquid. An oxidation tank made of fiberglass is installed, with air bubbling nozzles and a steam heater evenly distributed inside. After a certain amount of desulfurization waste liquid is fed into the oxidation tank, it is first heated by the steam heater and maintained at 80-85℃. Then, compressed air is introduced. Under the stirring and bubbling action of the air, the oxygen in the air comes into full contact with the desulfurization waste liquid, and an oxidation reaction occurs at this temperature.

[0010] This is the chemical equation for using air as an oxidant in this device: 2(NH4)2S2O3 + O2 = 2(NH4)2SO4 + 2S↓

[0011] This device uses oxygen from the air as an oxidant, resulting in a mild, safe, and reliable reaction that does not produce harmful waste gases, thus eliminating the dangers associated with the use of sulfuric acid in conventional process equipment. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0013] Figure 2 This is a top view of the present invention;

[0014] Figure 3 This is a schematic diagram of the main air pipe and the branch air pipe of this utility model;

[0015] Figure 4 This is a detailed schematic diagram of the aeration pipe of this utility model;

[0016] Figure 5 This is a schematic diagram of the steam inner coil and condensate inner coil of this utility model. Detailed Implementation

[0017] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings: Figure 1-5As shown, this utility model provides a technical solution: an air oxidation device for desulfurization wastewater, including a tank 1. The tank 1 contains an air aeration oxidation pipe, a condensate inner coil 12.1, and a steam inner coil 13.1. The air aeration oxidation pipe includes a main air pipe 5, a branch air pipe 5.1, and an aeration pipe 5.2. A vent pipe 10 is located at the center of the top of the tank 1. The vent pipe 10 has a flange at its head and its tail penetrates the tank 1, communicating with the interior of the tank 1. This allows for the discharge of media that could harm normal operation and maintenance, or for emergency venting to ensure the safety of personnel and equipment. A return pipe 9 is located on the left side of the vent pipe 10, allowing residual liquid from subsequent processes to be returned to the oxidation equipment for reprocessing. A material inlet pipe 8 is located on the right side of the vent pipe 10, allowing material to enter the tank. A material outlet pipe 7 is located on the bottom side wall of the tank 1. The wastewater to be treated enters the equipment through the inlet pipe, undergoes air oxidation, and is then discharged from the outlet pipe to the outside of the tank. A thermometer tube 6 is installed above the material outlet pipe 7. A thermometer can be installed inside the tube, and the operator can control the temperature of the medium inside the tank by displaying the temperature on the thermometer. An air main pipe 5 is also installed between the thermometer tube 6 and the material outlet pipe 7. The air main pipe 5 passes through the tank 1, with its head located outside the tank 1 and its tail extending into the tank 1. Air branch pipes 5.1 are connected to both sides of the air main pipe 5 inside the tank 1. An aeration pipe 5.2 is vertically installed on the air branch pipe 5.1. Aeration holes 5.3 are provided on the wall of the aeration pipe 5.2. A through hole penetrating the interior of the tank 1 is provided on the front outer wall of the tank 1. A steam inlet pipe 13 is provided at the through hole. One end of the steam inlet pipe 13 is located outside the tank 1, and the other end is fixedly connected to the steam inner coil 13.1. A through hole penetrating the interior of the tank 1 is provided on the left side of the steam inlet pipe 13. A condensate outlet pipe 12 is provided at the through hole. One end of the condensate outlet pipe 12 is located outside the tank 1, and the other end is fixedly connected to the condensate inner coil 12.1. After a certain amount of desulfurization waste liquid is fed into the oxidation tank, it is first heated by a steam heater and kept at 80-85℃. Then compressed air is introduced. Under the stirring and bubbling action of the air, the oxygen in the air comes into full contact with the desulfurization waste liquid, and an oxidation reaction occurs at this temperature.

[0018] The inner bottom surface of the tank body 1 is provided with an inner sloping bottom 4; the inner sloping bottom 4 gradually decreases from one end of the inner wall of the tank body 1 to one end of the material outlet 7, forming a sloping structure, which can effectively avoid the formation of dead corners at the bottom, thereby preventing material residue and waste.

[0019] Ten rows of aeration holes 5.3 are evenly arranged along the wall of the aeration pipe 5.2, with seven aeration holes 5.3 in each row from bottom to top. Air or oxygen can be injected into the medium through the aeration holes to improve the oxidation effect.

[0020] A ladder 11 is provided on the outside of the tank body 1, and a guardrail is also provided around the ladder 11 to protect the safety of workers going up and down the tank.

[0021] A top manhole 2 is located on the top of tank 1 near the ladder 11, and a bottom manhole 3 is located on the bottom of tank 1 near the bottom surface. The top manhole 2 can be used for the inspection and maintenance of the level gauge, so as to monitor the liquid level in the tank in real time and predict the amount of liquid stored in the tank. The bottom manhole 3 facilitates the cleaning and maintenance of the inside of the tank by the staff, removing impurities and dirt that have settled during long-term storage, so as to avoid affecting the quality of the medium or even causing damage to the tank.

[0022] A reserved swirl port A15 is provided between the manhole 3 at the bottom of the outer wall of the tank body 1 and the material outlet pipe 7. A reserved swirl port B16 is also provided on the other side of the outer wall of the tank body, which is symmetrical to the reserved swirl port A15. The two swirl ports can be circulated back through a conveying pump to increase the stirring effect.

[0023] A level gauge 17 is installed on the outer wall of tank 1.

[0024] A stirring port 14 is provided on the lower part of the outer wall of the tank body between the level gauge 17 and the reserved swirl port B16. When the air stirring effect is weak, an external stirrer can be connected to increase the stirring effect.

[0025] The working principle of this practical system is as follows: After the desulfurization wastewater enters the oxidation tank, the blower is started to pump air into the tank. Once the tank level reaches 1m, the side agitator is activated. After the influent volume reaches the specified value, the heating steam valve of the oxidation tank is opened, requiring the influent steam pressure to be controlled at 0.1MPa, with no significant vibration within the oxidation tank. The tail gas absorption device of the oxidation tank is then activated. The oxidation tank temperature is controlled at 80-85℃ and maintained at this temperature for 5 hours. During the air oxidation process, the tank temperature is automatically controlled, and the material continues to be heated to maintain a stable temperature. Samples are taken to analyze the ammonium thiosulfate content in the liquid within the oxidation tank; oxidation is complete when the content is ≤0.4-0.45%. The entire oxidation process takes approximately 20 hours.

[0026] The above is a specific embodiment of the present utility model. However, the specific embodiment of the present utility model is not limited to the above content. Without departing from the present utility model, appropriate modifications and replacements can be made to the device and components. If various modifications or variations of the present utility model do not depart from the spirit and scope of the present utility model, and if these modifications and variations fall within the scope of the claims and equivalent technologies of the present utility model, then the present utility model also intends to include these modifications and variations.

Claims

1. A desulfurization waste liquid air oxidation apparatus comprising a tank body (1), characterized in that: The tank body (1) is internally provided with an air aeration oxidation pipe, a condensate inner coil (12.1) and a steam inner coil (13.1); the air aeration oxidation pipe comprises an air main pipe (5), an air branch pipe (5.1) and an aeration pipe (5.2); the tank body (1) is provided at a top center position with a vent pipe (10), the vent pipe (10) is provided at a head portion with a flange interface and at a tail portion with a through hole penetrating the tank body (1) and communicating with the inside of the tank body (1); the vent pipe (10) is provided at a left side with a backflow pipe (9) and at a right side with a material inlet pipe (8); the tank body (1) is provided at a bottom side wall with a material outlet pipe (7); the material outlet pipe (7) is further provided above with a thermometer pipe (6); the thermometer pipe (6) and the material outlet pipe (7) are further provided between them with the air main pipe (5); the air main pipe (5) penetrates the tank body (1), is provided at a head portion outside the tank body (1) and at a tail portion inside the tank body (1); the air main pipe (5) is provided at both sides of a pipe body inside the tank body (1) with the air branch pipe (5.1); the air branch pipe (5.1) is vertically provided above with the aeration pipe (5.2); the aeration pipe (5.2) is provided at a pipe wall with aeration holes (5.3); the tank body (1) is internally provided at a bottom surface with an inner inclined bottom (4); the inner inclined bottom (4) gradually decreases from an inner wall of the tank body (1) to one end of the material outlet pipe (7), forming a slope-shaped structure; the tank body (1) is provided at a front outer wall with a through hole penetrating the inside of the tank body (1), the through hole is provided with a steam inlet pipe (13); one end of the steam inlet pipe (13) is arranged outside the tank body (1) and the other end is fixedly connected with the steam inner coil (13.1); the steam inlet pipe (13) is provided at a left side with a through hole penetrating the inside of the tank body (1), the through hole is provided with a condensate outlet pipe (12); one end of the condensate outlet pipe (12) is arranged outside the tank body (1) and the other end is fixedly connected with the condensate inner coil (12.1).

2. A device for air oxidation of desulphurization waste liquid according to claim 1, characterized in that: The aeration holes (5.3) are uniformly arranged in 10 rows along the pipe wall of the aeration pipe (5.2), and 7 aeration holes (5.3) are arranged in each row from bottom to top.

3. A device for air oxidation of desulphurization waste liquid according to claim 1, characterized in that: The tank body (1) is provided outside with a ladder (11), and a guardrail is further provided around the ladder (11).

4. A device for air oxidation of desulphurization waste liquid according to claim 3, characterized in that: The tank body (1) is provided at a top portion near one side of the ladder (11) with a top manhole (2) and at a bottom portion near a bottom surface with a bottom manhole (3).

5. A device for air oxidation of desulphurization waste liquid according to claim 4, characterized in that: The tank body (1) is provided between the bottom manhole (3) at a lower end of an outer wall and the material outlet pipe (7) with a reserved cyclone port A (15), and is further provided at a position symmetric to the reserved cyclone port A (15) with a reserved cyclone port B (16).

6. A device for air oxidation of desulphurization waste liquid according to claim 4, characterized in that: The tank body (1) is provided outside with a liquid level meter (17).

7. A device for air oxidation of desulphurization waste liquid according to claim 6, characterized in that: The tank body is provided outside with a stirring port (14) between the liquid level meter (17) and the reserved cyclone port B (16).

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