Waste sulfuric acid treatment system

Abstract

This invention provides a waste sulfuric acid treatment system, including a neutralization tank, a liquid ammonia storage device, and a Venturi mixer. The first inlet of the neutralization tank is used to transport the waste sulfuric acid to be treated into the tank. The first inlet of the Venturi mixer is connected to the first outlet of the neutralization tank via a first pipe. The first pipe is equipped with a circulation pump, and a discharge pipe is connected downstream of the circulation pump's outlet. A discharge control unit is installed on the discharge pipe. The second inlet of the Venturi mixer is connected to the liquid ammonia storage device via a second pipe. The second pipe is equipped with a liquid ammonia feed control unit. The outlet of the Venturi mixer is connected to the second inlet of the neutralization tank. A pH detection unit is used to detect the pH value of the liquid flowing out of the first outlet. A controller is electrically connected to the pH detection unit, the discharge control unit, and the liquid ammonia feed control unit. This invention enables continuous treatment of waste sulfuric acid with high neutralization efficiency.

Description

Technical Field

[0001] This utility model relates to a waste sulfuric acid treatment system. Background Technology

[0002] In chemical production processes, large quantities of waste sulfuric acid are often generated. Direct discharge of this waste sulfuric acid can cause serious environmental pollution. Currently, the main methods for treating waste sulfuric acid include neutralization, distillation, and regeneration. Neutralization is the most commonly used method, typically employing alkaline substances such as liquid ammonia or sodium hydroxide to react with the waste sulfuric acid to produce neutral salts. However, traditional neutralization processes often involve intermittent operation, resulting in low gas-liquid contact efficiency, long reaction times, and high energy consumption. Furthermore, traditional equipment is difficult to automate, is complex to operate, and has low production efficiency. Utility Model Content

[0003] The technical problem to be solved by this utility model is to overcome the defects of the prior art and provide a waste sulfuric acid treatment system that can achieve continuous operation and high neutralization reaction efficiency.

[0004] The present invention solves the above-mentioned technical problems through the following technical solution:

[0005] This utility model provides a waste sulfuric acid treatment system, which includes a neutralization tank, a liquid ammonia storage device, and a Venturi mixer;

[0006] The neutralization tank includes a first inlet, a second inlet, and a first outlet. The first inlet is used to transport the waste sulfuric acid to be treated into the neutralization tank.

[0007] The first input port of the Venturi mixer is connected to the first liquid outlet through a first pipe. The first pipe is equipped with a circulation pump. Downstream of the liquid outlet of the circulation pump, the first pipe is connected to an outlet pipe. The outlet pipe is equipped with a discharge control unit.

[0008] The second inlet of the Venturi mixer is connected to the liquid ammonia storage device through a second pipe. The second pipe is equipped with a liquid ammonia feed control unit. The outlet of the Venturi mixer is connected to the second inlet.

[0009] The waste sulfuric acid treatment system also includes a pH detection and control unit, which includes a pH detection unit and a controller. The pH detection unit is used to detect the pH value of the liquid flowing out from the first outlet, and the controller is electrically connected to the pH detection unit, the discharge control unit, and the liquid ammonia feed control unit.

[0010] In this scheme, the above-mentioned structure is adopted. By setting up a circulation structure with a Venturi mixer and a circulating pump, the continuous neutralization reaction of waste sulfuric acid and liquid ammonia in the neutralization tank is realized. The pH value of the liquid after the neutralization reaction is detected in real time by a pH detection unit, and the detected pH value is fed back to the controller. The controller determines whether the pH value meets the waste sulfuric acid treatment standard and controls the discharge of liquid ammonia from the liquid ammonia feed control unit in real time. At the same time, it controls the discharge of the treated liquid from the discharge control unit, thereby realizing the automation of the waste sulfuric acid treatment system and improving the mass transfer efficiency.

[0011] Preferably, the waste sulfuric acid treatment system includes a heat exchanger, which includes a first heat exchange pipe and a second heat exchange pipe. The inlet of the first heat exchange pipe is connected to the outlet of the circulating pump, and the outlet of the first heat exchange pipe is connected to the first inlet of the Venturi mixer. The second heat exchange pipe is used to introduce the liquid to be heat exchanged.

[0012] In this scheme, the above structure is adopted, and by setting up a heat exchanger, the heat generated by the neutralization reaction of waste sulfuric acid and liquid ammonia is recovered and utilized, thus saving energy.

[0013] Preferably, the heat exchanger is a plate heat exchanger or a shell-and-tube heat exchanger.

[0014] Preferably, the waste sulfuric acid treatment system includes a temperature detection mechanism for detecting the liquid temperature inside the neutralization tank;

[0015] And / or, the neutralization tank is equipped with a safety valve.

[0016] Preferably, the second pipeline is equipped with a flow meter for detecting the flow rate of liquid ammonia in the second pipeline, and the flow meter is electrically connected to the controller.

[0017] In this solution, the above structure is adopted. By setting up a flow meter, the amount of liquid ammonia discharged can be controlled more precisely, thereby controlling the neutralization reaction of waste sulfuric acid and liquid ammonia more accurately and improving the neutralization reaction efficiency.

[0018] Preferably, a first control valve is provided on the second pipeline upstream of the liquid ammonia feed control unit;

[0019] And / or, a second control valve is provided on the second pipeline downstream of the liquid ammonia feed control unit.

[0020] In this solution, the above structure is adopted, and the discharge of liquid ammonia can be better controlled by setting a control valve.

[0021] Preferably, the first control valve or the second control valve is electrically connected to the controller.

[0022] Preferably, the first pipe is provided with a liquid sampling port.

[0023] Preferably, the inlet or outlet of the circulating pump is equipped with a control valve.

[0024] In this scheme, the above structure is used to collect and test the liquid after the reaction at the liquid sampling port at irregular intervals, so that the discharged liquid meets the discharge requirements.

[0025] Preferably, the waste sulfuric acid treatment system further includes a waste sulfuric acid storage device, which is connected to the first liquid inlet via a liquid inlet pipe. The liquid inlet pipe is equipped with a feed pump for transporting waste sulfuric acid into the neutralization tank, and a valve is also provided on the liquid inlet pipe.

[0026] The positive and progressive effects of this utility model are as follows: Through the above-mentioned waste sulfuric acid treatment system, on the one hand, the continuous operation of the waste sulfuric acid treatment system is realized through the circulation structure composed of a Venturi mixer, a neutralization tank and a circulation pump; on the other hand, the pH detection and control system realizes precise control of the neutralization reaction and the discharge of liquid after desulfurization, realizes automated control, reduces manual intervention, and improves production safety and neutralization reaction efficiency. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the waste sulfuric acid treatment system according to an embodiment of the present invention.

[0028] Inlet pipe 1

[0029] Feed pump 2

[0030] Second Pipeline 3

[0031] Liquid ammonia feed control unit 4

[0032] Venturi Mixer 5

[0033] Safety valve 6

[0034] Thermometer 7

[0035] Neutralization tank 8

[0036] Downcomer 9

[0037] pH detection and control unit 10

[0038] Pipeline 11

[0039] Heat exchanger 12

[0040] Discharge control unit 13

[0041] Liquid outlet pipe 14

[0042] Sampling port 15

[0043] Circulation pump 16

[0044] Waste sulfuric acid storage device 17

[0045] Liquid ammonia storage device 18 Detailed Implementation

[0046] The present invention will be described more clearly and completely below with reference to the accompanying drawings, using a preferred embodiment as an example.

[0047] like Figure 1 As shown in the figure, this utility model embodiment discloses a waste sulfuric acid treatment system.

[0048] The waste sulfuric acid treatment system includes a neutralization tank 8, a liquid ammonia storage device 18, a venturi mixer 5, and a waste sulfuric acid storage device 17.

[0049] The neutralization tank 8 includes a first inlet, a second inlet, and a first outlet. The first inlet is used to transport the waste sulfuric acid to be treated into the neutralization tank 8.

[0050] In this embodiment, the first inlet is connected to the waste sulfuric acid storage device 17 through the inlet pipe 1. The inlet pipe 1 is equipped with a feed pump 2 for transporting waste sulfuric acid into the neutralization tank 8. Valves are provided upstream and downstream of the inlet pump 2. The second inlet is connected to the output port of the Venturi mixer 5 for transporting the liquid after mixing liquid ammonia and waste sulfuric acid in the Venturi mixer 5 into the neutralization tank 8.

[0051] The first inlet of the Venturi mixer 5 is connected to the first outlet through a first pipe. The first pipe is equipped with a circulation pump 16. The first pipe 11 is located downstream of the outlet of the circulation pump 16 and is connected to an outlet pipe 14. The outlet pipe 14 is equipped with a discharge control unit 13. The second inlet of the Venturi mixer 5 is connected to the liquid ammonia storage device 18 through a second pipe 3. The second pipe 3 is equipped with a liquid ammonia feed control unit 4. The outlet of the Venturi mixer 5 is connected to the second inlet.

[0052] The waste sulfuric acid treatment system also includes a pH detection and control unit 10, which includes a pH detection unit and a controller. The pH detection unit is used to detect the pH value of the liquid flowing out from the first outlet, and the controller is electrically connected to the pH detection unit, the discharge control unit 13 and the liquid ammonia feed control unit 4.

[0053] The pH detection unit detects the pH value of the mixed liquid flowing out of the first outlet of the neutralization tank 8 in real time and transmits the detected pH value to the controller via an electrical signal. The controller compares the detected pH value with the pH preset range stored in its internal memory and controls the opening or closing of the electromagnetic control valve of the discharge control unit 13 based on the comparison result. It also controls the liquid ammonia feed control unit 4 to adjust the flow rate of liquid ammonia so that the pH of the mixed liquid flowing out of the neutralization tank 8 meets the requirements.

[0054] Specifically, if the pH value detected by the pH detection unit is within the pH preset range stored in the controller, the mixed liquid is circulated back to the Venturi mixer 5 through the circulation pump 16 to continue the neutralization reaction. At the same time, the controller controls the discharge control unit 13 to open the electromagnetic control valve, so that a certain flow rate of mixed liquid flows out of the neutralization tank 8 through the liquid outlet pipe 14, and controls the liquid ammonia feed control unit 4 to keep the flow rate of liquid ammonia constant.

[0055] If the pH value detected by the pH detection unit is less than the minimum value of the pH preset range stored by the controller, the controller controls the discharge control unit 13 to close the electromagnetic control valve, so that the mixed liquid flowing out of the neutralization tank 8 is circulated back into the neutralization tank 8 through the first pipe 11 via the circulation pump 16 and the Venturi mixer 5 for another neutralization reaction, and controls the liquid ammonia feed control unit 4 to increase the flow rate of liquid ammonia.

[0056] If the pH value detected by the pH detection unit is greater than the maximum value of the pH preset range stored in the controller, the controller controls the discharge control unit 13 to close the electromagnetic control valve, so that the mixed liquid flowing out of the neutralization tank 8 is circulated back into the neutralization tank 8 through the first pipe 11 via the circulation pump 16 and the Venturi mixer 5 for another neutralization reaction, and controls the liquid ammonia feed control unit 4 to reduce the flow rate of liquid ammonia.

[0057] In this embodiment, a first control valve is installed on the second pipeline 3 upstream of the liquid ammonia feed control unit 4; a second control valve is installed on the second pipeline 3 downstream of the liquid ammonia feed control unit 4. The first and second control valves are electrically connected to the controller. A flow meter is also installed on the second pipeline 3, and the flow meter is electrically connected to the controller. The flow meter is used to detect the flow rate of liquid ammonia in the second pipeline 3. Both the first and second control valves are electromagnetic control valves.

[0058] The neutralization tank 8 is equipped with a liquid downcomer 9 connected to the second liquid inlet. The bottom of the liquid downcomer 9 extends to the bottom of the neutralization tank 8. The liquid downcomer 9 is used to transport the liquid mixture of liquid ammonia and waste sulfuric acid in the Venturi mixer 5 to the bottom of the neutralization tank 8. On the one hand, it avoids the mixed liquid from falling directly from the top of the neutralization tank 8 and causing impact to the neutralization tank 8. On the other hand, it can make the liquid ammonia and waste sulfuric acid fully neutralized.

[0059] Both the inlet and outlet of the circulating pump 16 are equipped with electromagnetic control valves. A liquid sampling port 15 is set on the first pipeline 11 connected downstream of the circulating pump 16 to periodically detect the pH value of the liquid after the neutralization reaction, and to help determine whether the neutralized liquid meets the discharge conditions.

[0060] In this embodiment, the neutralization tank 8 also includes a thermometer 7 and a safety valve 6. The thermometer 7 is used to detect the liquid temperature inside the neutralization tank.

[0061] In this embodiment, the waste sulfuric acid treatment system also includes a heat exchanger 12, which includes a first heat exchange pipe and a second heat exchange pipe. The inlet of the first heat exchange pipe is connected to the outlet of the circulating pump 16, and the outlet of the first heat exchange pipe is connected to the first inlet of the Venturi mixer 5. The second heat exchange pipe is used to introduce the liquid to be heat exchanged.

[0062] The heat exchanger 12 is a plate heat exchanger. When treating high-viscosity waste sulfuric acid, the heat exchanger 12 can also be a shell-and-tube heat exchanger.

[0063] The following provides a specific application of a waste sulfuric acid treatment system.

[0064] Waste sulfuric acid flows out from the waste sulfuric acid storage device 17 through the inlet pipe 1 and is continuously pumped into the neutralization tank 8 by the inlet pump 2 at a flow rate of 5-10 tons / hour. The circulation pump 16 extracts the waste sulfuric acid from the neutralization tank 8 at a flow rate of 15 m / s. The waste sulfuric acid extracted by the circulation pump 16 flows into the venturi mixer 5 through the first pipe 11. At the throat of the venturi mixer 5, the increased flow rate generates a negative pressure of 0.08 MPa, which draws in liquid ammonia from the liquid ammonia storage device 4. The waste sulfuric acid and liquid ammonia are mixed and neutralized in the venturi mixer 5. The mixture resulting from the neutralization reaction of waste sulfuric acid and liquid ammonia flows out through the outlet of the Venturi mixer 5, then flows into the neutralization tank 8 through the downcomer 9 connected to the Venturi mixer 5, and finally flows out through the first outlet of the neutralization tank 8. A pH detection unit monitors the pH value of the liquid flowing out of the neutralization tank 8 and transmits the detected pH information to the controller. The controller determines the pH value and controls the discharge control unit 13 and the liquid ammonia feed control unit 4 accordingly. The specific control method is as follows:

[0065] If 7.0≤pH≤7.5, the state of the liquid ammonia feed control unit 4 on the second pipeline 3 remains unchanged. The mixed liquid is circulated back to the Venturi mixer 5 through the circulation pump 16 to continue the neutralization reaction. At the same time, the electromagnetic control valve of the discharge control unit 13 is opened so that a certain flow rate of the neutralized mixed liquid flows out through the discharge pipeline.

[0066] If the pH value is <7.0, adjust the liquid ammonia feed control unit 4 to increase the flow rate of liquid ammonia into the Venturi mixer 5, and at the same time close the electromagnetic control valve of the discharge control unit 13.

[0067] If the pH value is greater than 7.5, adjust the liquid ammonia feed control unit 4 to reduce the flow rate of liquid ammonia into the Venturi mixer 5, and at the same time close the electromagnetic control valve of the discharge control unit 13.

[0068] When the mixed liquid flowing out of the first outlet does not meet the pH requirement, the mixed liquid continues to pass through the circulation pump 16 and is circulated back to the Venturi mixer 5 to continue the neutralization reaction. The above process is repeated continuously to achieve continuous treatment of waste sulfuric acid.

[0069] When the waste sulfuric acid treatment system is in operation, the mixed liquid circulated back to the Venturi mixer 5 by the circulating pump 16 will flow through the first heat exchange pipe of the heat exchanger 12. The liquid to be heated will be introduced into the second heat exchange pipe of the heat exchanger 12, where heat exchange will be achieved. The liquid will then be discharged from the outlet of the heat exchanger 12. This fully utilizes the heat generated by the neutralization reaction between liquid ammonia and waste sulfuric acid, achieving heat recovery and utilization, and saving energy.

[0070] The above-mentioned waste sulfuric acid treatment system can achieve continuous treatment of waste sulfuric acid. The system has a processing capacity of up to 10 tons of waste sulfuric acid per hour, a heat recovery rate of over 80%, and significantly reduces energy consumption by 20-30%.

[0071] While specific embodiments of this utility model have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this utility model is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this utility model, but all such changes and modifications fall within the scope of protection of this utility model.

Claims

1. A waste sulfuric acid treatment system, characterized in that, The waste sulfuric acid treatment system includes a neutralization tank, a liquid ammonia storage device, and a Venturi mixer; The neutralization tank includes a first inlet, a second inlet, and a first outlet. The first inlet is used to transport the waste sulfuric acid to be treated into the neutralization tank. The first input port of the Venturi mixer is connected to the first liquid outlet through a first pipe. The first pipe is equipped with a circulation pump. Downstream of the liquid outlet of the circulation pump, the first pipe is connected to an outlet pipe. The outlet pipe is equipped with a discharge control unit. The second inlet of the Venturi mixer is connected to the liquid ammonia storage device through a second pipe. The second pipe is equipped with a liquid ammonia feed control unit. The outlet of the Venturi mixer is connected to the second inlet. The waste sulfuric acid treatment system also includes a pH detection and control unit, which includes a pH detection unit and a controller. The pH detection unit is used to detect the pH value of the liquid flowing out from the first outlet, and the controller is electrically connected to the pH detection unit, the discharge control unit, and the liquid ammonia feed control unit.

2. The waste sulfuric acid treatment system as described in claim 1, characterized in that, The waste sulfuric acid treatment system includes a heat exchanger, which includes a first heat exchange pipe and a second heat exchange pipe. The inlet of the first heat exchange pipe is connected to the outlet of the circulating pump, and the outlet of the first heat exchange pipe is connected to the first inlet of the Venturi mixer. The second heat exchange pipe is used to introduce the liquid to be heat exchanged.

3. The waste sulfuric acid treatment system as described in claim 2, characterized in that, The heat exchanger is a plate heat exchanger or a shell-and-tube heat exchanger.

4. The waste sulfuric acid treatment system as described in claim 1, characterized in that, The waste sulfuric acid treatment system includes a temperature detection mechanism, which is used to detect the liquid temperature inside the neutralization tank. And / or, the neutralization tank is equipped with a safety valve.

5. The waste sulfuric acid treatment system as described in claim 1, characterized in that, The second pipeline is equipped with a flow meter for detecting the flow rate of liquid ammonia in the second pipeline, and the flow meter is electrically connected to the controller.

6. The waste sulfuric acid treatment system as described in claim 1, characterized in that, A first control valve is provided on the second pipeline upstream of the liquid ammonia feed control unit; And / or, a second control valve is provided on the second pipeline downstream of the liquid ammonia feed control unit.

7. The waste sulfuric acid treatment system as described in claim 6, characterized in that, The first control valve or the second control valve is electrically connected to the controller.

8. The waste sulfuric acid treatment system as described in claim 1, characterized in that, The first pipeline is equipped with a liquid sampling port.

9. The waste sulfuric acid treatment system as described in claim 1, characterized in that, The circulation pump is equipped with a control valve at its inlet or outlet.

10. The waste sulfuric acid treatment system as described in claim 1, characterized in that, The waste sulfuric acid treatment system also includes a waste sulfuric acid storage device, which is connected to the first liquid inlet through a liquid inlet pipe. The liquid inlet pipe is equipped with a feed pump for transporting waste sulfuric acid into the neutralization tank, and a valve is also provided on the liquid inlet pipe.

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