Dilute sulfuric acid recycling device

Abstract

The utility model discloses a dilute sulphuric acid recycling device which comprises a tail gas treatment device, a tail suction circulating pump, a dilute sulphuric acid pump, a filter, a density instrument, an acid concentration instrument and a dilute sulphuric acid storage tank, the tail suction circulating pump and the dilute sulphuric acid pump are arranged on the two sides of the tail gas treatment device respectively, and the dilute sulphuric acid storage tank is located at the tail end of one side of the tail suction circulating pump. The tail end located on one side of the dilute sulfuric acid pump is connected with the HRS-removing diluter, a density meter is arranged on one side of the tail gas treatment device, all the components are connected through conveying pipelines, the density meter is used for displaying the density of circulating liquid in the tail gas treatment device, and the acid concentration meter is used for displaying the acid concentration in the HRS diluter. The dilute sulphuric acid in the tail gas treatment device is conveyed to the filter through the conveying pipeline and then conveyed to the HRS diluter through the dilute sulphuric acid pump to replace part of demineralized water, and redundant dilute sulphuric acid is conveyed to the dilute sulphuric acid storage tank at the tail end through the tail suction circulating pump, so that the water supplementing amount and the wastewater treatment amount of the device are reduced, and meanwhile, the production cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of chemical technology, specifically to a dilute sulfuric acid recycling device. Background Technology

[0002] Currently, environmental protection and energy conservation have become key development goals for enterprises. In the process of producing sulfuric acid from sulfur, the environmental protection tail gas treatment devices all use hydrogen peroxide absorption. After absorption, dilute sulfuric acid containing hydrogen peroxide is produced. The common method for collecting this dilute sulfuric acid is to replace part of the makeup water required for the second absorption tower. This simple collection method has two drawbacks: First, in high humidity weather, less makeup water is needed for the second absorption tower, reducing the amount of dilute sulfuric acid recycled. This leads to overflow of the dilute sulfuric acid storage in the environmental protection tail gas treatment device, increasing the acid concentration and further inhibiting the tail gas treatment reaction. This results in increased hydrogen peroxide consumption, posing safety hazards. Excessive accumulation of dilute sulfuric acid can only be discharged as wastewater and requires neutralization, further increasing production costs. Second, in dry weather, excessive dilute sulfuric acid is recovered from the second absorption tower, resulting in excessively high hydrogen peroxide content in the finished sulfuric acid. This leads to excessively high iron content in the refined acid (battery sulfuric acid) produced in downstream devices, making it unusable as sulfuric acid. Therefore, a dilute sulfuric acid recycling device is needed. Utility Model Content

[0003] In view of the shortcomings of the prior art, this utility model discloses a dilute sulfuric acid recycling device to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a dilute sulfuric acid recycling device, comprising a tail gas treatment device, a tail gas suction circulation pump, a dilute sulfuric acid pump, a filter, a density meter, an acid concentration meter, and a dilute sulfuric acid storage tank.

[0005] The exhaust gas treatment device is equipped with an exhaust gas circulation pump and a dilute sulfuric acid pump on both sides. The dilute sulfuric acid storage tank is located at the tail end of the exhaust gas circulation pump. The tail end of the dilute sulfuric acid pump is connected to the HRS diluent. A density meter is installed on one side of the exhaust gas treatment device. An acid concentration meter is located between the HRS diluent and the dilute sulfuric acid pump. All components are connected by a conveying pipeline. The dilute sulfuric acid in the exhaust gas treatment device is conveyed through the conveying pipeline. The density meter displays the density of the circulating liquid in the exhaust gas treatment device, and the acid concentration meter displays the acid concentration in the HRS diluent. A filter, which is a Y-type filter, is installed between the exhaust gas treatment device and the dilute sulfuric acid pump. The dilute sulfuric acid in the exhaust gas treatment device is conveyed to the filter through the conveying pipeline and then conveyed to the HRS diluent by the dilute sulfuric acid pump to replace part of the demineralized water. At the same time, the excess dilute sulfuric acid is conveyed to the dilute sulfuric acid storage tank at the end by the exhaust gas circulation pump.

[0006] Preferably, a check valve is provided on the delivery pipeline at the outlet of the dilute sulfuric acid pump. The check valve is made of PTFE-lined material. The check valve prevents the high-temperature, high-concentration sulfuric acid in the HRS diluent from flowing back into the dilute sulfuric acid pump through the delivery pipeline. At the same time, a check valve is also provided at the inlet of the HRS diluent.

[0007] Preferably, a flow meter is installed on the delivery pipe at the outlet of the dilute sulfuric acid pump. The flow meter is an electromagnetic flow meter, and the internal material of the electromagnetic flow meter is PFA or an equivalent sulfuric acid corrosion-resistant material. The flow meter can transmit data to the DCS. Based on the value on the flow meter, the frequency conversion adjustment operation of the dilute sulfuric acid pump is performed. If the data of the circulating liquid density meter 1 is too high, and the data of the HRS diluter acid concentration meter 7 is too low, the frequency conversion of the dilute sulfuric acid pump 4 is turned off. At the same time, the excess dilute sulfuric acid is transported to the dilute sulfuric acid storage tank 9 through the tail suction circulation pump for the production of 50%-70% acid.

[0008] Preferably, a pneumatic regulating valve is provided at the inlet of the dilute sulfuric acid storage tank. The pneumatic regulating valve is equipped with an intelligent electric positioner and a filter pressure reducing device. The density of the circulating liquid is controlled by the pneumatic regulating valve so that the density meter displays normal data.

[0009] Preferably, the conveying pipeline is a steel-lined PTFE pipeline.

[0010] Preferably, the dilute sulfuric acid pump is a hydraulic dual-diaphragm alarm metering pump, the material of the dilute sulfuric acid pump is PTFE-lined, the diaphragm pressure value of the dilute sulfuric acid pump can be displayed on the DCS, when the diaphragm pressure value is "0" it means the pump is operating normally, otherwise it means the pump is faulty, the dilute sulfuric acid pump is equipped with a frequency converter, and the frequency is remotely adjusted through the DCS to control the reuse flow.

[0011] Preferably, the dilute sulfuric acid storage tank is located within the refined acid unit area, and the dilute sulfuric acid storage tank is made of steel lined with PTFE.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0013] 1. In this utility model, the dilute sulfuric acid produced from the tail gas treatment device can be completely recycled and reused through the dilute sulfuric acid recycling device, and the manufacturing cost of this set of equipment is low.

[0014] 2. This invention reduces the amount of manual labor required by employees, avoiding the risk of burns. It also reduces the amount of water needed for equipment replenishment and wastewater treatment, further lowering production costs and reducing wastewater discharge pressure. Attached Figure Description

[0015] The accompanying drawings are provided to further understand 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 and do not constitute a limitation thereof.

[0016] In the attached diagram:

[0017] Figure 1 This is a schematic diagram of the dilute sulfuric acid recycling device of this utility model;

[0018] The following are labeled in the diagram: 1. Density meter; 2. Delivery pipeline; 3. Filter; 4. Dilute sulfuric acid pump; 5. Check valve; 6. Flow meter; 7. Acid concentration meter; 8. Pneumatic regulating valve; 9. Dilute sulfuric acid storage tank; 10. Tail-end circulation pump; 11. HRS diluter; 12. Tail gas treatment device. Detailed Implementation

[0019] 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.

[0020] Example: Figure 1 As shown, a dilute sulfuric acid recycling device includes a tail gas treatment device 12, a tail gas circulation pump 10, a dilute sulfuric acid pump 4, a filter 3, a density meter 1, an acid concentration meter 7, and a dilute sulfuric acid storage tank 9.

[0021] The tail gas treatment device 12 is equipped with a tail suction circulation pump 10 and a dilute sulfuric acid pump 4 on both sides. The dilute sulfuric acid pump 4 is a hydraulic double diaphragm alarm metering pump, and its material is PTFE-lined. The diaphragm pressure value of the dilute sulfuric acid pump 4 can be displayed on the DCS. When the diaphragm pressure value is "0", it means that the pump is operating normally; otherwise, it means that the pump is faulty. The dilute sulfuric acid pump 4 is equipped with a frequency converter, and the frequency can be remotely adjusted through the DCS to control the reuse flow. The dilute sulfuric acid storage tank 9 is located at the tail end of the tail suction circulation pump 10. The dilute sulfuric acid storage tank 9 is located in the refined acid unit area, and its material is steel lined with PTFE. The tail end of the dilute sulfuric acid pump 4 is connected to the HRS diluter 11. A density meter 1 is installed on one side of the tail gas treatment device 12. The density meter 1 is based on the mass flow rate and is resistant to dilute sulfuric acid corrosion. The acid concentration meter... 7 is located between the HRS diluter 11 and the dilute sulfuric acid pump 4, and all components are connected by a conveying pipe 2. The conveying pipe 2 is a steel-lined PTFE pipe. The dilute sulfuric acid in the tail gas treatment device 12 is conveyed through the conveying pipe 2. The density of the circulating liquid in the tail gas treatment device 12 is displayed by the density meter 1, and the acid concentration in the HRS diluter 11 is displayed by the acid concentration meter 7. A filter 3 is provided between the tail gas treatment device 12 and the dilute sulfuric acid pump 4. The filter 3 is a Y-type filter 3. The dilute sulfuric acid in the tail gas treatment device 12 is conveyed to the filter 3 through the conveying pipe 2, and then conveyed to the HRS diluter 11 by the dilute sulfuric acid pump 4 to replace part of the demineralized water. At the same time, the excess dilute sulfuric acid is conveyed to the dilute sulfuric acid storage tank 9 at the end by the tail suction circulation pump 10.

[0022] Specifically, a check valve 5 is provided on the conveying pipe 2 located at the outlet of the dilute sulfuric acid pump 4. The check valve 5 is made of PTFE-lined material. The check valve 5 prevents the high-temperature and high-concentration sulfuric acid in the HRS diluter 11 from flowing back into the dilute sulfuric acid pump 4 through the conveying pipe 2. At the same time, a check valve 5 is also provided at the inlet of the HRS diluter 11.

[0023] Specifically, a flow meter 6 is installed on the conveying pipe 2 located at the outlet of the dilute sulfuric acid pump 4. The flow meter 6 is an electromagnetic flow meter 6. The internal material of the electromagnetic flow meter 6 is PFA or an equivalent sulfuric acid corrosion resistant material. The flow meter 6 can transmit data to the DCS. Based on the value on the flow meter 6, the frequency conversion adjustment operation of the dilute sulfuric acid pump 4 is performed. If the data of the circulating liquid density meter 11 is too high, and the data of the acid concentration meter 77 of the HRS diluter 11 is too low, the frequency conversion of the dilute sulfuric acid pump 44 is turned off. At the same time, the excess dilute sulfuric acid is transported to the dilute sulfuric acid storage tank 99 through the tail suction circulation pump 10 for the production of 50%-70% acid.

[0024] Specifically, a pneumatic regulating valve 8 is provided at the inlet of the dilute sulfuric acid storage tank 9. The pneumatic regulating valve 8 is equipped with an intelligent electric positioner and a filter pressure reducing device. The density of the circulating liquid is controlled by the pneumatic regulating valve 8 so that the data displayed by the density meter 1 is normal.

[0025] Working Principle: Based on the density of the circulating liquid in the tail gas treatment device 12 (displayed by density meter 1) and the acid concentration in the HRS diluent 11 (displayed by acid concentration meter 7), the dilute sulfuric acid in the tail gas treatment device 12 is filtered through the dilute sulfuric acid pipeline and then pumped to the HRS diluent 11 by the dilute sulfuric acid pump 4, replacing part of the demineralized water. The dilute sulfuric acid pump 4 is regulated by frequency conversion. To prevent high-temperature, high-concentration sulfuric acid in the HRS diluent 11 from flowing back into the dilute sulfuric acid pump 4 through the dilute sulfuric acid pipeline, a check valve 5 is installed at the outlet of the dilute sulfuric acid pump 4, and a check valve 5 is also installed at the inlet of the HRS diluent 11. The operator adjusts the frequency conversion of the dilute sulfuric acid pump 4 in the DCS according to the flow meter 6 on the dilute sulfuric acid pipeline at the outlet of the dilute sulfuric acid pump 4. If the data displayed by the circulating liquid density meter 1 is too high, and the data displayed by the acid concentration meter 7 in the HRS diluent 11 is too low, the frequency conversion of the dilute sulfuric acid pump 4 is reduced, and the excess dilute sulfuric acid is pumped to the dilute sulfuric acid storage tank 9 through the tail suction circulation pump 10 for the production of 50%-70% acid. During this period, the density of the circulating liquid is controlled by the pneumatic regulating valve 8, so that the data displayed by the density meter 1 is normal.

[0026] 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 sulfuric acid recycling device, characterized in that: This includes an exhaust gas treatment device, an exhaust gas circulation pump, a dilute sulfuric acid pump, a filter, a density meter, an acid concentration meter, and a dilute sulfuric acid storage tank. The exhaust gas treatment device is equipped with an exhaust gas circulation pump and a dilute sulfuric acid pump on both sides. The dilute sulfuric acid storage tank is located at the tail end of the exhaust gas circulation pump. The tail end of the dilute sulfuric acid pump is connected to the HRS diluent. A density meter is installed on one side of the exhaust gas treatment device. An acid concentration meter is located between the HRS diluent and the dilute sulfuric acid pump. All components are connected by a conveying pipeline. The dilute sulfuric acid in the exhaust gas treatment device is conveyed through the conveying pipeline. The density meter displays the density of the circulating liquid in the exhaust gas treatment device, and the acid concentration meter displays the acid concentration in the HRS diluent. A filter is installed between the exhaust gas treatment device and the dilute sulfuric acid pump. The dilute sulfuric acid in the exhaust gas treatment device is conveyed to the filter through the conveying pipeline and then conveyed to the HRS diluent by the dilute sulfuric acid pump to replace part of the demineralized water. At the same time, the excess dilute sulfuric acid is conveyed to the dilute sulfuric acid storage tank at the end by the exhaust gas circulation pump.

2. The dilute sulfuric acid recycling device according to claim 1, characterized in that: A check valve is installed on the delivery pipeline at the outlet of the dilute sulfuric acid pump. The check valve is made of PTFE-lined material. The check valve prevents the high-temperature, high-concentration sulfuric acid in the HRS diluent from flowing back into the dilute sulfuric acid pump through the delivery pipeline. At the same time, a check valve is also installed at the inlet of the HRS diluent.

3. The dilute sulfuric acid recycling device according to claim 1, characterized in that: A flow meter is installed on the delivery pipeline at the outlet of the dilute sulfuric acid pump. The flow meter is an electromagnetic flow meter. The internal material of the electromagnetic flow meter is PFA or an equivalent sulfuric acid corrosion resistant material. The flow meter can transmit data to the DCS, and the frequency conversion adjustment operation of the dilute sulfuric acid pump can be performed based on the value on the flow meter.

4. The dilute sulfuric acid recycling device according to claim 1, characterized in that: A pneumatic regulating valve is installed at the inlet of the dilute sulfuric acid storage tank. The pneumatic regulating valve is equipped with an intelligent electric positioner and a filter pressure reducing device. The density of the circulating liquid is controlled by the pneumatic regulating valve so that the density meter displays normal data.

5. A dilute sulfuric acid recycling device according to claim 1, characterized in that: The conveying pipeline is a steel-lined PTFE pipeline.

6. A dilute sulfuric acid recycling device according to claim 1, characterized in that: The dilute sulfuric acid pump is a hydraulic dual-diaphragm alarm metering pump. The dilute sulfuric acid pump is made of PTFE-lined material. The diaphragm pressure value of the dilute sulfuric acid pump can be displayed on the DCS. The dilute sulfuric acid pump is equipped with a frequency converter, and the frequency can be remotely adjusted through the DCS to control the reuse flow.

7. A dilute sulfuric acid recycling device according to claim 1, characterized in that: The dilute sulfuric acid storage tank is located within the refined acid unit area, and the dilute sulfuric acid storage tank is made of steel lined with PTFE.

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