A harmless treatment system for chromium-containing waste liquid

Abstract

The utility model discloses a kind of harmless disposal systems of chromium-containing waste liquid, involve waste liquid processing field.The utility model provides a kind of harmless disposal systems of chromium-containing waste liquid, including the reduction reaction pool, sedimentation tank, filter tank and pH adjusting pool and control module connected in turn, reduction reaction pool is equipped with liquid inlet, the top of reduction reaction pool is equipped with first support frame, first support frame is equipped with reducing agent feeding device, temperature control device and first stirring device are equipped in reduction reaction pool, pH detecting instrument for real-time detection pH value is equipped in pH adjusting pool, the top of pH adjusting pool is equipped with second support frame, acid-base feeding device and second stirring device are equipped on second support frame, control module is connected with reducing agent feeding device, temperature control device, first stirring device, pH detecting instrument, acid-base feeding device, second stirring device signal respectively, wherein, control module controls the feeding amount of acid-base feeding device according to the data of pH detecting instrument feedback to adjust the pH value in pH adjusting pool.

Description

Technical Field

[0001] This utility model relates to the field of waste liquid treatment, specifically to a harmless treatment system for chromium-containing waste liquid. Background Technology

[0002] In industrial production, many industries generate chromium-containing wastewater, such as electroplating, leather tanning, printing and dyeing, and metal processing. If this chromium-containing wastewater is discharged directly without proper treatment, it will cause serious environmental pollution, endangering human health and ecological balance. Currently, common methods for treating chromium-containing wastewater mainly include chemical reduction precipitation, ion exchange, membrane separation, and adsorption. Among these, chemical reduction precipitation is widely used. Its principle is to add a reducing agent to the wastewater to reduce the highly toxic and carcinogenic hexavalent chromium to the relatively less toxic trivalent chromium. Then, the pH value of the wastewater is adjusted so that the trivalent chromium combines with hydroxide ions to form water-insoluble chromium hydroxide precipitate, thereby achieving separation from water and removing chromium.

[0003] pH value has a crucial impact on the precipitation of trivalent chromium; excessively acidic or alkaline environments can lead to incomplete precipitation of chromium hydroxide. However, traditional methods for measuring pH and adding acid or alkali are often intermittent or manual, resulting in slow response times and an inability to achieve stable and precise pH adjustment, making it difficult for the effluent to consistently meet standards. Utility Model Content

[0004] The purpose of this invention is to overcome the above-mentioned technical problems and provide a harmless treatment system for chromium-containing waste liquid.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is: a harmless treatment system for chromium-containing waste liquid, comprising a reduction reaction tank, a sedimentation tank, a filtration tank, and a pH adjustment tank connected in sequence, as well as a control module. The reduction reaction tank is provided with an inlet, and a first support frame is provided above the reduction reaction tank. A reducing agent dosing device is provided on the first support frame. A temperature control device and a first stirring device are provided inside the reduction reaction tank. A pH meter for real-time pH value detection is provided inside the pH adjustment tank. A second support frame is provided above the pH adjustment tank, and an acid-base dosing device and a second stirring device are provided on the second support frame. The control module is connected to the reducing agent dosing device, the temperature control device, the first stirring device, the pH meter, the acid-base dosing device, and the second stirring device via signals. The control module controls the dosing amount of the acid-base dosing device according to the data fed back by the pH meter to adjust the pH value in the pH adjustment tank.

[0006] Furthermore, the reducing agent dispensing device includes a storage tank, a discharge pipe, and a solenoid valve. The storage tank is mounted on the first support frame, the discharge pipe is located at the bottom of the storage tank and communicates with the storage tank, and the solenoid valve is mounted on the discharge pipe to control the opening and closing of the discharge pipe.

[0007] Furthermore, the temperature control device includes a heating tube and a temperature sensor. Both the heating tube and the temperature sensor are disposed on the inner wall of the reduction reaction tank, and both the heating tube and the temperature sensor are signal-connected to the control module.

[0008] Furthermore, the first stirring device includes a stirring motor, a stirring shaft, and a stirring rod. The stirring motor is mounted on the first support frame, the stirring shaft is connected to the stirring motor and extends into the reduction reaction tank, and the stirring rod is mounted on the stirring shaft and located within the reduction reaction tank.

[0009] Furthermore, the stirring motor is a servo motor.

[0010] Furthermore, the acid-base dispensing device has the same structure as the reducing agent dispensing device.

[0011] Furthermore, the second stirring device has the same structure as the first stirring device.

[0012] Furthermore, the bottom of the sedimentation tank is inclined.

[0013] Furthermore, the bottom of the sedimentation tank is provided with a sludge discharge port for discharging sludge.

[0014] As can be seen from the above description of this utility model, compared with the prior art, the harmless treatment system for chromium-containing waste liquid provided by this utility model has the following advantages: by setting up a reduction reaction tank, a sedimentation tank, a filtration tank, a pH adjustment tank, and corresponding reducing agent dosing device, acid and alkali dosing device, a first stirring device, a second stirring device, a temperature detection device, a pH meter, and a control module, the system realizes automated and precise treatment of chromium-containing waste liquid. Among them, the temperature control device and the first stirring device in the reduction reaction tank ensure that the reduction reaction is fully carried out, and the pH meter in the pH adjustment tank that detects the pH value in real time and the acid and alkali dosing device that automatically adds acid and alkali ensures stable and precise pH adjustment, so that the effluent consistently meets the standards. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the chromium-containing waste liquid harmless treatment system of this utility model.

[0016] Figure 2 This is a front view of the chromium-containing waste liquid harmless treatment system of this utility model.

[0017] Figure 3 This is a schematic diagram of the reducing agent dispensing device.

[0018] Figure 4 This is a schematic diagram of the first stirring device. Detailed Implementation

[0019] The technical solutions of this 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 this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0020] Reference Figures 1-4 As shown, a harmless treatment system for chromium-containing waste liquid includes a reduction reaction tank 1, a sedimentation tank 2, a filtration tank 3, and a pH adjustment tank 4 connected in sequence, as well as a control module. The reduction reaction tank 1 is provided with an inlet 11 through which the chromium-containing waste liquid enters the reduction reaction tank 1. A first support frame 12 is provided above the reduction reaction tank 1, and a reducing agent dosing device 5 is provided on the first support frame 12. The reduction reaction tank 1 is provided with a temperature control device 6 and a first stirring device 7. The temperature control device 6 is used to maintain a suitable temperature required for the reduction reaction to improve the reduction reaction efficiency. The first stirring device 7 is used to accelerate the mixing reaction of the reducing agent and the waste liquid. The pH adjustment tank 4 is equipped with a pH meter 41 for real-time pH monitoring. A second support frame 42 is located above the pH adjustment tank 4, and an acid / alkali dispensing device 8 and a second stirring device 9 are mounted on the second support frame 42. The control module is connected to the reducing agent dispensing device 5, the temperature control device 6, the first stirring device 7, the pH meter 41, the acid / alkali dispensing device 8, and the second stirring device 9. The control module controls the amount of acid / alkali dispensing agent dispensed by the acid / alkali dispensing device 8 based on the data fed back by the pH meter 41 to adjust the pH value in the pH adjustment tank 4 so that the pH value of the waste liquid reaches neutrality to meet the discharge standards.

[0021] The reducing agent dispensing device 5 includes a storage tank 51, a discharge pipe 52, and a solenoid valve 53. The storage tank 51 is mounted on the first support frame 12, and the discharge pipe 52 is located at the bottom of the storage tank 51 and is connected to the storage tank 51. The solenoid valve 53 is mounted on the discharge pipe 52 to control the opening and closing of the discharge pipe 52, thereby controlling the dispensing of the reducing agent.

[0022] The temperature control device 6 includes a heating tube 61 and a temperature sensor 62. Both the heating tube 61 and the temperature sensor 62 are disposed on the inner wall of the reduction reaction tank 1, and both are signal-connected to the control module. Specifically, the temperature sensor 62 monitors the temperature inside the reduction reaction tank 1 in real time. When the temperature is lower than a set value, the control module activates the heating tube 61 to heat the tank, ensuring the reduction reaction proceeds at a suitable temperature.

[0023] The first stirring device 7 includes a stirring motor 71, a stirring shaft 72, and a stirring rod 73. The stirring motor 71 is mounted on the first support frame 12, and the stirring shaft 72 is connected to the stirring motor 71 and extends into the reduction reaction tank 1. The stirring rod 73 is mounted on the stirring shaft 72 and is located within the reduction reaction tank 1. The stirring motor 71 is a servo motor, which allows for precise control of the stirring speed and time.

[0024] The acid-base dispensing device 8 has the same structure as the reducing agent dispensing device 5.

[0025] The second stirring device 9 has the same structure as the first stirring device 7.

[0026] The bottom of the sedimentation tank 2 is inclined, and the bottom of the sedimentation tank 2 is provided with a sludge discharge port 21 for discharging sludge.

[0027] The filter tank 3 includes a coarse filter layer and a fine filter layer. The coarse filter layer uses materials such as quartz sand to intercept larger suspended particles and sediments. The fine filter layer uses materials such as activated carbon to further adsorb residual impurities and harmful substances in the waste liquid, ensuring that the effluent water quality meets the standards.

[0028] During operation, chromium-containing waste liquid enters the reduction reaction tank 1 through the inlet 11. Under the control of the control module, the reducing agent dosing device 5 adds the reducing agent according to the set amount, while the temperature control device 6 maintains a suitable reaction temperature. The first stirring device 7 stirs to evenly disperse the reducing agent, reducing hexavalent chromium to trivalent chromium. Subsequently, the waste liquid flows into the sedimentation tank 2. Under the action of the inclined bottom, trivalent chromium precipitate settles at the bottom and is discharged through the sludge discharge port 21. Afterward, the waste liquid passes through the filtration tank 3 to further remove suspended solids and impurities, and then enters the pH adjustment tank 4. Here, the pH meter monitors the pH value in real time and feeds it back to the control module. The control module controls the acid-base dosing device 8 to add acid and alkali, and the second stirring device 9 stirs to ensure thorough mixing and precise pH adjustment, allowing trivalent chromium to fully combine with hydroxide ions to form chromium hydroxide precipitate, ultimately achieving the harmless treatment of the waste liquid and ensuring that the effluent meets discharge standards.

[0029] The above are only some specific embodiments of this utility model, but the design concept of this utility model is not limited thereto. Any non-substantial modifications made to this utility model using this concept shall be considered as an infringement of the protection scope of this utility model.

Claims

1. A system for the harmless treatment of chromium-containing waste liquid, characterized in that: The system includes a reduction reaction tank, a sedimentation tank, a filtration tank, and a pH adjustment tank connected in sequence, as well as a control module. The reduction reaction tank has an inlet, and a first support frame is provided above the reduction reaction tank. A reducing agent dosing device is provided on the first support frame. A temperature control device and a first stirring device are provided inside the reduction reaction tank. A pH meter for real-time pH value detection is provided inside the pH adjustment tank. A second support frame is provided above the pH adjustment tank, and an acid / base dosing device and a second stirring device are provided on the second support frame. The control module is connected to the reducing agent dosing device, the temperature control device, the first stirring device, the pH meter, the acid / base dosing device, and the second stirring device. The control module controls the dosing amount of the acid / base dosing device based on the data fed back by the pH meter to adjust the pH value in the pH adjustment tank.

2. The chromium-containing waste liquid harmless treatment system according to claim 1, characterized in that: The reducing agent dispensing device includes a storage tank, a discharge pipe, and a solenoid valve. The storage tank is mounted on the first support frame, the discharge pipe is located at the bottom of the storage tank and is connected to the storage tank, and the solenoid valve is mounted on the discharge pipe to control the opening and closing of the discharge pipe.

3. The chromium-containing waste liquid harmless treatment system according to claim 2, characterized in that: The temperature control device includes a heating tube and a temperature sensor. The heating tube and the temperature sensor are both disposed on the inner wall of the reduction reaction tank, and the heating tube and the temperature sensor are both signal connected to the control module.

4. The chromium-containing waste liquid harmless treatment system according to claim 3, characterized in that: The first stirring device includes a stirring motor, a stirring shaft, and a stirring rod. The stirring motor is mounted on the first support frame, the stirring shaft is connected to the stirring motor and extends into the reduction reaction tank, and the stirring rod is mounted on the stirring shaft and located in the reduction reaction tank.

5. The chromium-containing waste liquid harmless treatment system according to claim 4, characterized in that: The stirring motor is a servo motor.

6. The chromium-containing waste liquid harmless treatment system according to claim 5, characterized in that: The acid-base dispensing device has the same structure as the reducing agent dispensing device.

7. The chromium-containing waste liquid harmless treatment system according to claim 6, characterized in that: The second stirring device has the same structure as the first stirring device.

8. The chromium-containing waste liquid harmless treatment system according to claim 7, characterized in that: The bottom of the sedimentation tank is inclined.

9. The chromium-containing waste liquid harmless treatment system according to claim 8, characterized in that: The bottom of the sedimentation tank is equipped with a sludge discharge port for discharging sludge.

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