Diluted acid flash evaporation cooling device for copper smelting

Abstract

The utility model discloses a dilute acid flash evaporation cooling device for copper smelting, and particularly relates to the field of nonferrous metallurgy, the dilute acid flash evaporation cooling device comprises an upper shell and a lower shell, the top end of the upper shell is provided with a negative pressure extraction opening, one side of the lower shell is provided with a liquid inlet, and the liquid inlet is communicated with a liquid inlet pipe; the other side of the lower shell is provided with a compressed air inlet, and the compressed air inlet is connected with a compressed air pipe; a rubber liner is mounted on the inner wall of the lower shell, and a cavity is formed between the inner wall of the lower shell and the rubber liner; a discharge port is formed in the bottom end of the lower shell, the discharge port is communicated with a discharge pipeline, the discharge pipeline is communicated with a crystallization pipe and a concentrated acid pipe, a pipe opening of the crystallization pipe is formed in the crystal receiving tank, and a pipe opening of the concentrated acid pipe is formed in the concentrated acid storage tank. Before the waste acid liquid is filtered, the cooling process is carried out, and substances easy to crystallize in the waste acid liquid are separated out, so that the problem of filter membrane blockage caused by substance crystallization and separation in the waste acid filtering process is solved.

Description

Technical Field

[0001] This utility model relates to the field of non-ferrous smelting technology, specifically to a dilute acid flash evaporation and cooling device for copper smelting. Background Technology

[0002] The high-temperature acidic wastewater generated during the flue gas purification process in the non-ferrous smelting industry is called "waste acid." This waste acid has a complex composition, mainly containing high concentrations of arsenic, sulfate ions, fluoride ions, and chloride ions, as well as small amounts of metal ions such as copper, zinc, lead, and cadmium. It is a highly hazardous and difficult-to-treat type of smelting industrial wastewater. Currently, large-scale copper smelting enterprises in China mainly use lime neutralization, sulfide precipitation, and lime-iron salt methods to treat waste acid. Some enterprises, such as the copper smelting industry, also prepare waste acid into sulfuric acid or treat it before returning it to the upstream stage for continued flue gas absorption, depending on the characteristics of the waste acid in their production process.

[0003] Typically, waste acid is treated by filtration and impurity removal followed by the preparation of sulfuric acid or further processing before being returned to the upstream end for flue gas absorption, thus achieving the purpose of recycling. However, current applications have found that when the temperature of the waste acid solution decreases, some ionic substances in the liquid will crystallize and precipitate, adhering to the inner sides of the filtration equipment and the filter membrane, reducing the efficiency of filtration and impurity removal, accelerating the replacement of the filter membrane, and shortening the service life of the filtration equipment.

[0004] Therefore, a new device needs to be considered to first cool down the high-temperature waste acid, precipitate easily crystallizable substances, and then further treat the acidic liquid to ensure the smooth progress of the waste acid treatment process, while recovering crystallized substances according to the temperature range. Utility Model Content

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0006] This utility model discloses a copper smelting dilute acid flash cooling device, comprising an upper shell and a lower shell, wherein the upper shell and the lower shell are connected by a flange, and a negative pressure exhaust port is provided at the top of the upper shell, the negative pressure exhaust port is connected to a steam pipeline, and the other end of the steam pipeline is connected to a negative pressure extraction device; a pressure sensor is also installed on one side of the upper shell.

[0007] A liquid inlet is provided on one side of the lower housing, and a liquid inlet pipe is connected to the liquid inlet. A compressed air inlet is provided on the other side of the lower housing, and the compressed air inlet is connected to a compressed air pipe. A rubber liner is installed on the inner wall of the lower housing, and there is a cavity between the inner wall of the lower housing and the rubber liner.

[0008] The bottom of the lower shell is provided with a discharge port, which is connected to a discharge pipeline. The discharge pipeline is connected to a crystallization pipe and a concentrated acid pipe. The outlet of the crystallization pipe is located inside the crystallization receiving tank, and the outlet of the concentrated acid pipe is located inside the concentrated acid storage tank.

[0009] As a preferred embodiment of this utility model, a second pneumatic control valve is installed on the steam pipeline.

[0010] As a preferred technical solution of this utility model, the liquid inlet pipe is equipped with a pneumatic control valve and a compressed air control valve, and the liquid inlet pipe is connected to a storage tank through a liquid pump, the storage tank containing high-temperature waste acid.

[0011] As a preferred embodiment of this invention, the cavity is connected to the compressed air inlet.

[0012] As a preferred embodiment of this utility model, a pneumatic control valve three is installed on the concentrated acid tube, and a pneumatic control valve four is installed on the crystallization tube.

[0013] As a preferred embodiment of this invention, the liquid inlet is connected to the interior of the lower shell.

[0014] The beneficial effects of this utility model are: 1. Before filtering the waste acid liquid, the device first carries out a cooling process to precipitate easily crystallizable substances in the waste acid solution, thereby improving the problem of filter membrane blockage caused by the crystallization of substances during the waste acid filtration process.

[0015] 2. The device operates automatically during operation and controls each process through pressure recognition, which optimizes the problem that traditional level gauges are easily covered by crystals, leading to inaccurate level signal recognition.

[0016] 3. This device innovatively utilizes compressed air and the elastic deformation of rubber, allowing the crystals to detach and be collected, achieving a preliminary separation effect;

[0017] 4. The device is equipped with gas backflushing at the liquid inlet to blow off most of the water in the crystals, which facilitates the shedding of the crystals.

[0018] 5. The upper and lower shells of the device are connected by flanges, which facilitates maintenance and the installation and replacement of the rubber liner. The rubber liner is only installed in the lower part.

[0019] 6. The steam generated by this device can convert sensible heat into latent heat and absorb it. As the steam is transported through pipelines, a heat exchanger or condenser can be installed at the downstream end to convert and utilize the heat in the steam. The steam is condensed into water and can be reused. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0021] Figure 1 This is a schematic diagram of the structure of a dilute acid flash cooling device for copper smelting according to the present invention.

[0022] Figure 2 This is a schematic diagram of a dilute acid flash cooling device for copper smelting according to the present invention.

[0023] In the diagram: 1. Upper shell; 2. Lower shell; 3. Rubber inner liner; 4. Cavity; 5. Pneumatic control valve one; 6. Pneumatic control valve two; 7. Pneumatic control valve three; 8. Pneumatic control valve four; 9. Crystallization receiving tank; 10. Concentrated acid storage tank; 11. Pressure sensor; 12. Negative pressure exhaust port; 13. Steam pipeline; 14. Liquid inlet; 15. Compressed air control valve. Detailed Implementation

[0024] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0025] Example: Figure 1 and Figure 2 As shown, this utility model discloses a copper smelting dilute acid flash cooling device, comprising an upper shell 1 and a lower shell 2. The upper shell 1 is made of stainless steel with an anti-corrosion lining. The upper shell 1 and the lower shell 2 are connected by a flange. A negative pressure exhaust port 12 is provided at the top of the upper shell 1, which is connected to a steam pipeline 13. A pneumatic control valve 6 is installed on the steam pipeline 13, and the other end of the steam pipeline 13 is connected to a negative pressure extraction device. The negative pressure extraction device can be used to extract negative pressure when the internal pressure of the upper shell 1 is too high. A pressure sensor 11 is also installed on one side of the upper shell 1, which can monitor the internal pressure of the device.

[0026] A liquid inlet 14 is provided on one side of the lower housing 2, and the liquid inlet 14 communicates with the interior of the lower housing 2. A liquid inlet pipe is connected to the liquid inlet 14, and a pneumatic control valve 5 and a compressed air control valve 15 are installed on the liquid inlet pipe, and the two valves are interlocked. The liquid inlet pipe is connected to a storage tank containing high-temperature waste acid via a liquid pump. The high-temperature waste acid in the storage tank is pumped into the device for treatment. When it is pumped into the device, the pneumatic control valve 5 is open, and the compressed air control valve 15 is closed.

[0027] A compressed air inlet is provided on the other side of the lower housing 2, and the compressed air inlet is connected to a compressed air pipe; a rubber liner 3 is installed on the inner wall of the lower housing 2, and there is a cavity 4 between the inner wall of the lower housing 2 and the rubber liner 3; the cavity 4 is connected to the compressed air inlet. When compressed air enters the cavity 4, it can cause the rubber liner 3 to be squeezed and deformed.

[0028] The lower shell 2 has a discharge port at its bottom, which is connected to a discharge pipeline. The discharge pipeline is connected to a crystallization pipe and a concentrated acid pipe. The outlet of the crystallization pipe is located inside the crystallization receiving tank 9, and the outlet of the concentrated acid pipe is located inside the concentrated acid storage tank 10. A pneumatic control valve 3 7 is installed on the concentrated acid pipe, and a pneumatic control valve 4 8 is installed on the crystallization pipe.

[0029] Working principle:

[0030] ① Cooling and Crystallization: The high-acid waste acid solution is pumped from the storage tank into the flash evaporation unit. At this time, the liquid pressure is B, which is much greater than the internal pressure A of the unit (A is slightly lower than atmospheric pressure). After the waste acid enters the unit, due to the sudden drop in pressure, the boiling point of the liquid decreases accordingly, causing the waste acid liquid to vaporize rapidly. That is, the water in the liquid flashes into water vapor, reducing the water content and concentrating the waste acid. Heat is absorbed in the form of latent heat, and the temperature of the waste acid liquid decreases accordingly. After the temperature of the waste acid liquid decreases, some ions, such as As... 2+ They will adhere to the rubber inner liner 3 inside the flash evaporator in the form of crystalline substances.

[0031] Throughout the process, the negative pressure device is activated to continuously extract the water vapor generated in the device, controlling the internal pressure to remain stable within a range that ensures efficient cooling and crystallization. The pressure value is monitored in real time by the pressure sensor 11 installed on the upper shell 1, and the negative pressure device is adjusted accordingly. As the cooling and crystallization process proceeds, the waste acid solution concentrates at the bottom of the device, and crystals gradually form on the side wall of the rubber inner liner to a certain thickness.

[0032] ② Material collection:

[0033] a. Concentrated waste acid: After the device has been running for a period of time (the specific time is determined by the liquid characteristics, device volume, and commissioning, with the time node being the volume of concentrated waste acid reaching a certain position within the device volume), the negative pressure device is turned off. At this time, flash evaporation continues, and the internal pressure of the equipment increases. When the pressure reaches atmospheric pressure (monitored and controlled by pressure sensor 11), the bottom pneumatic valve 3.7 of the lower shell 2 is opened, and the concentrated waste acid is discharged to the concentrated acid storage tank 10. After the bottom waste acid is discharged, the pneumatic valve 3.7 is closed, and at the same time, the negative pressure device is turned on to extract the residual water vapor inside the device. When the pressure drops to A, a new round of cooling and crystallization begins.

[0034] b. Water vapor: Extracted by the negative pressure device and enters the subsequent waste gas treatment system along steam pipeline 13.

[0035] c. Crystalline substances:

[0036] Drying: After the system has run for several cycles (the specific cycle is determined by the characteristics of the waste acid and the crystallization situation), close the liquid inlet gas control valve 5 and open the compressed air control valve 15 at the liquid inlet to blow air into the device to remove the moisture from the material attached to the rubber inner liner 3 (the specific blowing time is determined by the material characteristics, on-site debugging, etc.).

[0037] Crystallization removal: After the blowing is completed, close the compressed air control valve 15, draw the negative pressure control valve 6, open the compressed air inlet on the side of the lower shell 2, and intermittently introduce compressed air into the cavity 4 between the lower shell 2 and the rubber inner liner 3. The air pressure causes the rubber inner liner 3 to deform, and the deformation can cause the crystallized material attached to the rubber inner liner 3 to fall off.

[0038] Crystallization collection: The blown-off crystals gather at the bottom of the device under the action of gravity. Then, the compressed air control valve 15 is closed and the bottom air control valve 48 is opened. The crystals are discharged into the crystallization receiving tank 9 for storage and further processing.

[0039] ③Where to dispose of concentrated acid:

[0040] The water quality parameters of acidic wastewater after flue gas scrubbing are simple and easy to handle. After cooling, concentration and impurity removal, sulfuric acid can be further prepared by roasting, absorption tower absorption and other methods.

[0041] When the acidic wastewater after flue gas scrubbing contains many complex pollutants that are difficult to prepare sulfuric acid, the acidic solution after cooling, concentration and impurity removal can be returned to the front end for flue gas absorption. After a certain cycle, the concentrated acidic solution reaches the set concentration. A portion of the concentrated acid is sent to the back end for treatment and can be discharged after meeting the standards. The other portion of the concentrated acid is replenished with water and then returned to the front end for flue gas absorption.

[0042] The operation of the device is controlled by an existing PLC. As the flash cooling proceeds, the pressure changes of the device at different stages are read by the pressure sensor 11, and the corresponding signals are sent to the control system. The automatic control system adjusts the operation process of flash cooling according to the preset program.

[0043] It should be noted that: 1. The valves in the patent include, but are not limited to, pneumatic flexible valves, pneumatic butterfly valves, and pneumatic ball valves. The selection and use of valves are ultimately determined by the characteristics of the materials, and the selection of valves is something that a person skilled in the art would easily think of.

[0044] 2. The inner liner of the device in the patent is made of rubber, but in practical applications, it can be replaced with a material that is more suitable for the material properties and is prone to deformation. The choice of inner liner is something that a person skilled in the art would easily think of.

[0045] 3. The connection method (flange connection, upper and lower shells) and the coverage area of ​​the inner liner (lower shell) of the device described in the patent can be changed to an integrated (closed) or adhesive type, depending on the application environment and the material of the inner liner.

[0046] 4. The top of the upper housing 1 of the device in the patent can be equipped with a pneumatic control / exhaust valve, which changes the internal air pressure of the device to be close to atmospheric pressure by exhausting air, thereby allowing the concentrated waste acid to flow into the concentrated acid storage tank by gravity.

[0047] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A dilute acid flash cooling device for copper smelting, comprising an upper shell (1) and a lower shell (2), the upper shell (1) and the lower shell (2) being connected by a flange, characterized in that, The top end of the upper shell (1) is provided with a negative pressure air outlet (12), the negative pressure air outlet (12) communicates with a steam pipeline (13), and the other end of the steam pipeline (13) is communicated with a negative pressure extraction device; a pressure sensor (11) is also installed on one side of the upper shell (1); The lower shell (2) is provided with a liquid inlet (14) on one side, the liquid inlet (14) is communicated with a liquid inlet pipe, the other side of the lower shell (2) is provided with a compressed air inlet, and the compressed air inlet is connected with a compressed air pipe; a rubber liner (3) is installed on the inner wall of the lower shell (2), and there is a cavity (4) between the inner wall of the lower shell (2) and the rubber liner (3); The bottom end of the lower shell (2) is provided with a discharge port, the discharge port is communicated with a discharge pipeline, the discharge pipeline is communicated with a crystallization pipe and a concentrated acid pipe, and the pipe opening of the crystallization pipe is arranged in a crystallization receiving groove (9), and the pipe opening of the concentrated acid pipe is arranged in a concentrated acid storage tank (10).

2. The device for reducing the temperature of dilute acid flash from copper smelting according to claim 1, characterized in that, The steam pipeline (13) is provided with a pneumatic control valve two (6).

3. The device for reducing the temperature of dilute sulfuric acid from copper smelting according to claim 1, characterized in that, The liquid inlet pipe is provided with a pneumatic control valve one (5) and a compressed air control valve, and the liquid inlet pipe is connected with a storage tank through a liquid pump, and the storage tank is filled with high-temperature waste acid.

4. The device for reducing the temperature of dilute sulfuric acid from copper smelting according to claim 1, characterized in that, The cavity (4) is communicated with the compressed air inlet.

5. The device for reducing the temperature of dilute sulfuric acid from copper smelting according to claim 1, characterized in that, The concentrated acid pipe is provided with a pneumatic control valve three (7), and the crystallization pipe is provided with a pneumatic control valve four (8).

6. The device for reducing the temperature of dilute sulfuric acid from copper smelting according to claim 1, characterized in that, The liquid inlet (14) is communicated with the inside of the lower shell (2).

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