Extraction device and process for producing hydrogen peroxide by anthraquinone method

Abstract

The application provides an extraction device and process for producing hydrogen peroxide by an anthraquinone method. The device comprises an extraction tower, a high-concentration hydrogen peroxide discharge port arranged at the bottom of the extraction tower, a feed inlet arranged at the lower part of the extraction tower, and a water inlet arranged at the upper part of the extraction tower. A raffinate phase discharge port is arranged at the top of the extraction tower and is connected to a raffinate separator through a pipeline. A light phase outlet is arranged at the upper part of the raffinate separator, and a heavy phase outlet is arranged at the lower part of the raffinate separator. The heavy phase outlet is connected to multiple outlet pipelines according to different hydrogen peroxide concentrations after passing through a hydrogen peroxide concentration controller. The outlet pipeline with low hydrogen peroxide concentration is connected to a back feeding port of the extraction tower. The device and process can realize high extraction concentration, high extraction efficiency, controllable product concentration, and the like. Meanwhile, the device is provided with a safety interlocking system, which can effectively reduce the risk of over-temperature and over-pressure accidents.

Description

TECHNICAL FIELD

[0001] The application relates to a hydrogen peroxide production technology field, in particular to an anthraquinone method hydrogen peroxide high-efficiency extraction device and process. BACKGROUND

[0002] At present, most of the hydrogen peroxide devices in operation have a product hydrogen peroxide concentration of 27.5-35% (mass percent), and it is difficult to directly produce hydrogen peroxide products with a concentration of more than 35%. The organic impurities in the hydrogen peroxide prepared by using the concentration technology increase exponentially, which has an adverse effect on the product quality of the downstream production chain. With the continuous progress of caprolactam production technology, higher requirements are put forward for the concentration of hydrogen peroxide. Therefore, it is urgent to research a hydrogen peroxide high-efficiency extraction technology to efficiently produce high-concentration hydrogen peroxide under the premise of safety. SUMMARY

[0003] The application provides an extraction device and process for producing hydrogen peroxide by an anthraquinone method, which can realize high extraction concentration, high extraction efficiency, controllable product concentration and the like, and a safety interlocking system is arranged in the device, so that the risk of over-temperature and over-pressure accidents can be effectively reduced.

[0004] The technical scheme of the application is an extraction device for producing hydrogen peroxide by an anthraquinone method, which comprises an extraction tower, the bottom of the extraction tower is provided with a high-concentration hydrogen peroxide discharge port, the lower part is provided with a feed inlet, and the upper part is provided with a water inlet; the top of the extraction tower is provided with a raffinate phase discharge port, which is connected to a raffinate separator through a pipeline; the upper part of the raffinate separator is provided with a light phase outlet, and the lower part is provided with a heavy phase outlet; a plurality of outlet pipelines are connected to the heavy phase outlet according to different concentrations of hydrogen peroxide, and the outlet pipeline with low hydrogen peroxide concentration is connected to a back feeding port of the extraction tower.

[0005] Further, the back feeding port is located between the feed inlet and the water inlet of the extraction tower, the back feeding port is provided in plurality, the heavy phase outlet of the raffinate separator is connected to different back feeding ports through different outlet pipelines, and the lower the concentration of hydrogen peroxide is, the higher the position of the corresponding back feeding port is.

[0006] Further, two back feeding ports are arranged at different heights between the feed inlet and the water inlet of the extraction tower, the outlet pipeline with a hydrogen peroxide concentration of less than 15 wt% is connected to the upper back feeding port, the outlet pipeline with a hydrogen peroxide concentration of 15-27.5 wt% is connected to the lower back feeding port, and the heavy phase outlet is further provided with an outlet pipeline for collecting hydrogen peroxide with a concentration of more than 27.5 wt%.

[0007] Further, the top of the extraction tower is provided with a nitrogen adding pipeline and a venting pipeline and a venting valve, and is further provided with a pressure sensor, the nitrogen and the venting valve are associated with a pressure control loop, and the venting pipeline is further provided with an oxygen concentration detection device.

[0008] Further, the raffinate separator is longitudinally divided into three stages along the flow direction of the working liquid, and the three stages are inclined plate settling separation, packing layer separation and coalescing collector separation in sequence.

[0009] Further, the upper, middle and lower towers of the extraction column are respectively provided with temperature sensors, and an emergency material withdrawal valve is arranged at the bottom of the extraction column.

[0010] Further, temperature sensors are arranged in front, middle and rear of the raffinate separator, and an accident material withdrawal valve is further arranged on the outlet pipeline of the rear of the heavy phase outlet, and the temperature sensors of the raffinate separator are interlocked with the accident material withdrawal valve.

[0011] Further, an overflow pipeline is arranged at the top of the extraction column.

[0012] The present application also relates to an extraction process for producing hydrogen peroxide by anthraquinone method, comprising the following steps:

[0013] S1, the working liquid containing hydrogen peroxide enters from the feed port of the extraction column, and pure water at 50-60 DEG C enters the upper part of the extraction column through the water inlet, and the hydrogen peroxide in the working liquid of the extraction column is extracted by countercurrent pure water; the top discharge is the working liquid containing low concentration hydrogen peroxide, which enters the raffinate separator; the high concentration hydrogen peroxide discharge port at the bottom of the extraction column extracts 45-50% hydrogen peroxide;

[0014] S2, the material in the raffinate separator is first subjected to preliminary separation by inclined plate settling, the settled hydrogen peroxide heavy phase enters the coalescing collector, and the working liquid is added to the packing layer for further extraction, the extracted hydrogen peroxide enters the coalescing collector, and the working liquid is further separated by coalescing, and the content of hydrogen peroxide is controlled to be below 0.1 g / L, which is collected as light phase; the heavy phase discharge at the bottom of the raffinate separator is a certain concentration of hydrogen peroxide, and the discharge is controlled according to the concentration of hydrogen peroxide or returned to the extraction column for re-extraction.

[0015] Further, when the concentration of the heavy phase discharge at the bottom of the raffinate separator is higher than 27.5%, it is extracted as a finished product, when the concentration is 15-27.5%, it is returned to the middle and lower parts of the extraction column for re-extraction, and when the concentration is lower than 15%, it is returned to the upper part of the extraction column for re-extraction.

[0016] Further, three temperature sensors are arranged at the upper, middle and lower positions of the same layer of the extraction column. When two of the three temperatures of any layer are greater than or equal to 55°C and the temperature rising rate is greater than or equal to 2°C / min, and / or the temperature is greater than or equal to 60°C, the extraction column bottom is discharged. For example, when two of the three temperatures are greater than or equal to 55°C and the temperature rising rate is greater than or equal to 2°C / min, the extraction column bottom is discharged. Or when two of the three temperatures are greater than or equal to 60°C, the extraction column bottom is discharged. Or when one of the three temperatures is greater than or equal to 55°C and the temperature rising rate is greater than or equal to 2°C / min, and the other temperature is greater than or equal to 60°C, the extraction column bottom is discharged. Three temperature sensors are arranged at the front, middle and rear positions of the raffinate separator. When two of the three temperatures of any position are greater than or equal to 55°C and the temperature rising rate is greater than or equal to 2°C / min, and / or the temperature is greater than or equal to 60°C, the heavy phase outlet pipe and the accident discharge valve are discharged. For example, when two of the three temperatures are greater than or equal to 55°C and the temperature rising rate is greater than or equal to 2°C / min, the heavy phase outlet pipe and the accident discharge valve are discharged. Or when two of the three temperatures are greater than or equal to 60°C, the heavy phase outlet pipe and the accident discharge valve are discharged. Or when one of the three temperatures is greater than or equal to 55°C and the temperature rising rate is greater than or equal to 2°C / min, and the other temperature is greater than or equal to 60°C, the heavy phase outlet pipe and the accident discharge valve are discharged.

[0017] The present application has the following beneficial effects:

[0018] 1. By controlling the water inflow and outflow of the extraction column, the ratio of the working liquid feed amount to the pure water feed amount is controlled to be 30-50:1, and 45-50% high-concentration hydrogen peroxide is directly extracted from the extraction column, which effectively improves the extraction concentration. The hydrogen peroxide content in the raffinate liquid carried by the extraction column top is controlled to be 0.5-2g / L. The current hydrogen peroxide production technology cannot ensure that the hydrogen peroxide content in the raffinate liquid is less than 0.3g / L, thereby restricting the increase of the extraction concentration of the extraction column. The present technology adopts a split control to extract, and realizes one-time extraction of 45-50% high-concentration hydrogen peroxide.

[0019] 2. Since the hydrogen peroxide content carried by the raffinate liquid increases, it will affect the subsequent process, and the separation of hydrogen peroxide in the raffinate working liquid is crucial. The raffinate working liquid is extracted by using a high-efficiency raffinate separator, through coalescence separation + split extraction technology, to realize the graded split extraction of hydrogen peroxide with different concentrations. The extraction is freely adjusted according to the concentration, and when the concentration is higher than 27.5%, it is extracted into the finished product tank; when the concentration is 15-27.5%, the hydrogen peroxide at the bottom of the high-efficiency raffinate separator is discharged into the middle and lower parts of the extraction column; and when the concentration is lower than 15%, the hydrogen peroxide at the bottom of the high-efficiency raffinate separator is discharged into the middle and upper parts of the extraction column.

[0020] 3. The high-efficiency raffinate separator can effectively adjust and control the hydrogen peroxide content in the top raffinate liquid, and ensure that the working liquid quality meets the standards.

[0021] 4. By comprehensive regulation of the extraction tower and raffinate separator, different concentration hydrogen peroxide products can be effectively produced, the extraction efficiency is improved, the hydrogen peroxide product quality is improved compared with concentration, and energy consumption is saved;

[0022] 5. The extraction tower temperature setting interlock automatically opens the tower head nitrogen when the temperature is too high, and when the temperature is further too high, the bottom material return valve is opened to return the high-temperature material out of the system, thereby greatly reducing the system operation safety risk. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a structural schematic diagram of the present application. DETAILED DESCRIPTION

[0024] The embodiments of the present application will be described in detail below with reference to examples, but those skilled in the art will understand that the following examples are only for illustration of the present application and should not be regarded as limiting the scope of the present application.

[0025] Example 1:

[0026] As shown in Figure 1 An extraction device for producing hydrogen peroxide by anthraquinone method, the device comprises an extraction tower 1, the extraction tower bottom is provided with a high-concentration hydrogen peroxide discharge port 1-1, the lower part is provided with a feed port 1-2, and the upper part is provided with a water inlet 1-3; the top of the extraction tower is provided with a raffinate phase discharge port 1-4, which is connected to a raffinate separator 2 through a pipeline; the upper part of the raffinate separator is provided with a light phase outlet 2-1, and the lower part is provided with a heavy phase outlet 2-2, the heavy phase outlet is connected to multiple outlet pipelines according to different concentrations of hydrogen peroxide, and the outlet pipeline with low concentration of hydrogen peroxide is connected to the extraction tower return port 1-5.

[0027] In a preferred case, the return port 1-5 is located between the feed port 1-2 and the water inlet 1-3 of the extraction tower, the return port is provided in multiple, the heavy phase outlet of the raffinate separator is connected to different return ports through different outlet pipelines, and the lower the concentration of hydrogen peroxide, the higher the corresponding return port position.

[0028] Preferably, two return ports are provided at different heights between the feed port and the water inlet of the extraction tower, the outlet pipeline with hydrogen peroxide concentration below 15wt% is connected to the upper return port, the outlet pipeline with hydrogen peroxide concentration of 15-27.5wt% is connected to the lower return port, and the heavy phase outlet is further provided with an outlet pipeline with hydrogen peroxide concentration above 27.5wt%. The heavy phase outlet can be provided with a mass flow meter, a densimeter, a thermometer, a real-time online concentration display instrument, etc., to realize real-time detection of the concentration of hydrogen peroxide, and different flow discharges are selected according to different concentrations.

[0029] Preferably, the top of the extraction column is provided with a nitrogen addition pipeline 1-6, a venting pipeline 1-7 and a venting valve, and a pressure sensor, a nitrogen and venting valve associated pressure control circuit, and an oxygen concentration detection device 1-8 on the venting pipeline. Specifically, the top of the extraction column is normally kept at a slight positive pressure, i.e. 1-3 kPa, nitrogen is added in time when the pressure is lower than 1 kPa to avoid inhaling air, and the venting valve is appropriately opened to reduce the pressure when the pressure is higher than 3 kPa. The other function of the nitrogen addition pipeline is to cooperate with the oxygen concentration detection device, and nitrogen is added in time to replace the gas phase space when the oxygen content detected exceeds 8% to ensure safe operation.

[0030] Preferably, the upper, middle and lower columns of the extraction column are respectively provided with temperature sensors, and the bottom of the extraction column is provided with an emergency material withdrawal valve, and the temperature gauges of the upper, middle and lower columns of the extraction column are interlocked with the emergency material withdrawal valve. Specifically, three temperature sensors are respectively arranged at the same horizontal position of different parts of the upper, middle and lower columns of the extraction column, and when two of the three temperature points in the upper part reach the interlocking temperature, the interlocking action opens the emergency material withdrawal valve to realize material withdrawal, and similarly, when two of the three temperature points in the middle part reach the interlocking temperature, the interlocking action opens the emergency material withdrawal valve to realize material withdrawal, and when two of the three temperature points in the lower part reach the interlocking temperature, the interlocking action opens the emergency material withdrawal valve to realize material withdrawal.

[0031] Preferably, the front, middle and rear of the raffinate separator inlet and outlet are respectively provided with temperature sensors, and the outlet pipeline after the heavy phase outlet is further provided with an emergency material withdrawal valve, and the front, middle and rear temperature gauges of the raffinate separator are interlocked with the emergency material withdrawal valve. Specifically, three temperature sensors are respectively arranged at the same vertical position of different parts of the front, middle and rear of the raffinate separator inlet and outlet, and when two of the three temperature points in the front part reach the interlocking temperature, the interlocking action opens the emergency material withdrawal valve to realize material withdrawal, and similarly, when two of the three temperature points in the middle part reach the interlocking temperature, the interlocking action opens the emergency material withdrawal valve to realize material withdrawal, and when two of the three temperature points in the rear part reach the interlocking temperature, the interlocking action opens the emergency material withdrawal valve to realize material withdrawal.

[0032] Preferably, the top of the extraction column is provided with an overflow pipeline 1-9 to prevent liquid overflow in abnormal conditions.

[0033] The raffinate separator is longitudinally divided into three stages along the flow direction of the working liquid, and is sequentially provided with a tilted plate settling separation, a packing layer separation, and a coalescing collector separation. The working liquid containing low-concentration hydrogen peroxide is discharged from the top of the extraction column and then enters the raffinate separator, and is first subjected to preliminary separation by the tilted plate settling. The settled heavy phase of hydrogen peroxide enters the coalescing collector. A small amount of hydrogen peroxide in the working liquid is further settled when passing through the packing layer. The packing layer is designed by micro-channel extraction. A small amount of pure water is added before the working liquid enters the packing layer. The hydrogen peroxide in the working liquid is extracted as the working liquid passes through the packing layer. The extracted hydrogen peroxide enters the coalescing collector through the channel at the bottom of the coalescing collector. The working liquid containing a small amount of hydrogen peroxide after passing through the packing layer enters the next stage of separation, and the small amount of hydrogen peroxide in the working liquid is further removed by high-efficiency coalescing separation. The content of hydrogen peroxide in the light phase outlet of the raffinate separator is controlled to be less than or equal to 0.1 g / L, and the working liquid is obtained to be recycled after regeneration. The heavy phase discharged from the bottom of the raffinate separator is high-concentration hydrogen peroxide, which is discharged according to the concentration of hydrogen peroxide or returned to the extraction column for re-extraction.

[0034] The extraction column in the device uses a staged addition of extractant for the heavy phase reflux of the raffinate separator according to the concentration gradient, further strengthening the extraction effect. The extraction column bottom discharge can extract 45-50% concentration hydrogen peroxide.

[0035] Example 2:

[0036] When the above device is used for extraction of hydrogen peroxide produced by the anthraquinone method, the specific process is as follows:

[0037] The working liquid containing hydrogen peroxide enters from the bottom inlet of the extraction column, and its concentration is 7-12 g / L. Pure water at 50-60°C enters the upper part of the extraction column through the water inlet, and the pure water countercurrently passes through the hydrogen peroxide in the working liquid.

[0038] The raffinate phase after extraction (the concentration of hydrogen peroxide is 0.5-2 g / L) enters the raffinate separator from the top outlet. After the tilted plate settling, the packing separation, and the coalescing separation, the concentration of hydrogen peroxide in the light phase working liquid can be less than or equal to 0.1 g / L. When the concentration of the heavy phase discharged from the bottom of the raffinate separator is higher than 27.5%, it is taken out as a finished product. When the concentration is 15-27.5%, it is returned to the lower part of the extraction column for re-extraction. When the concentration is less than 15%, it is returned to the upper part of the extraction column for re-extraction. By using the gradient of the extraction column and adopting multi-stage reflux feeding, the extraction concentration of the extraction column discharge can be improved to 45-50% according to the concentration distribution of the staged extraction.

[0039] In the extraction process, in order to ensure the safety of the system, three temperature sensors are arranged at the upper, middle and lower positions of the same layer of the extraction tower. When two of the three temperatures of any layer are greater than or equal to 55°C and the temperature rising rate is greater than or equal to 2°C / min, and / or the temperature is greater than or equal to 60°C, the extraction tower bottom discharge is used; three temperature sensors are arranged at the front, middle and rear positions of the raffinate separator, and when two of the three temperatures of any place are greater than or equal to 55°C and the temperature rising rate is greater than or equal to 2°C / min, and / or the temperature is greater than or equal to 60°C, the discharge is carried out through the pipeline of the heavy phase outlet and the accident discharge valve. The above conditions are met at any one of the three temperature detection positions and two detection points, which can prevent false operation of a single instrument and improve safety performance.

[0040] Comparative Example 1:

[0041] The working solution containing hydrogen peroxide is fed into the bottom inlet of the extraction tower, and the concentration is 7-12 g / L. Pure water at 50-60°C is fed into the upper part of the extraction tower through the water inlet, and the pure water flows countercurrently through the hydrogen peroxide in the working solution of the extraction tower.

[0042] The raffinate phase after extraction is not treated and reused. In order to ensure that the hydrogen peroxide content in the raffinate phase is below 0.1 g / L under the same conditions, the amount of pure water used as the extractant will increase by 1-3 m 3 / h. The large amount of pure water added leads to a significant decrease in the concentration gradient in the extraction tower, and the extraction concentration of the extraction tower decreases to the interval of 27.5-35%.

[0043] Comparative Example 2:

[0044] The working solution containing hydrogen peroxide is fed into the bottom inlet of the extraction tower, and the concentration is 7-12 g / L. Pure water at 50-60°C is fed into the upper part of the extraction tower through the water inlet, and the pure water flows countercurrently through the hydrogen peroxide in the working solution of the extraction tower.

[0045] The raffinate phase after extraction is treated and reused by a simple separation process, such as a traditional raffinate separator. On the one hand, it is necessary to ensure that the hydrogen peroxide content of the raffinate phase discharged from the top of the extraction tower is below 0.1 g / L to ensure the safe operation of the subsequent process, which leads to a decrease in the overall concentration gradient of the extraction tower and a significant decrease in the extraction efficiency of the extraction tower. On the other hand, the heavy phase separated by the raffinate separator has a hydrogen peroxide concentration of only 0.5-3%, and this part of the low-concentration hydrogen peroxide is returned to the bottom of the extraction tower, which reduces the amount of pure water added as the extractant and further reduces the extraction efficiency, thereby further reducing the hydrogen peroxide concentration of the extraction discharge. Under the same conditions, the extraction concentration of the extraction tower can be controlled in the interval of 27.5-33%.

[0046] Comparative Example 3:

[0047] The working solution containing hydrogen peroxide is fed from the bottom inlet of the extraction tower, with a concentration of 7-12 g / L, and pure water at 50-60°C is fed into the upper part of the extraction tower through the water inlet, and the pure water flows countercurrently through the hydrogen peroxide in the working solution of the extraction tower;

[0048] The raffinate phase after extraction (the concentration of hydrogen peroxide is >2 g / L) is discharged from the top outlet into the raffinate separator, and after inclined plate settling, packing separation and coalescence separation, the concentration of hydrogen peroxide in the light phase working solution can reach as low as 0.5 g / L, which causes safety hazards to the operation of the subsequent process and poses a great safety risk.

[0049] The raffinate phase after extraction (the concentration of hydrogen peroxide is <0.5 g / L) is discharged from the top outlet into the raffinate separator, and after inclined plate settling, packing separation and coalescence separation, the concentration of hydrogen peroxide in the light phase working solution can reach below 0.1 g / L. However, due to the low concentration of the raffinate separator feed, the concentration of the heavy phase after separation continues to be below 5%, and this part of low-concentration hydrogen peroxide is returned to the upper part of the extraction tower for re-extraction, which can improve the extraction effect to a certain extent, but the extraction concentration of the extraction tower is difficult to reach above 45%.

[0050] In Example 3, when the concentration of hydrogen peroxide collected from the bottom of the raffinate separator is higher than 27.5%, it is directly collected into the product tank. As the hydrogen peroxide is collected at a rate of 1-3 m 3 / h, the hydrogen peroxide in the extraction tower gradually decreases, the concentration of hydrogen peroxide in the working solution at the top of the extraction tower gradually decreases, the hydrogen peroxide discharged from the extraction tower to the raffinate separator correspondingly decreases, and the concentration of hydrogen peroxide collected from the bottom gradually decreases. When the concentration is as low as 15-27.5%, the hydrogen peroxide discharged from the bottom of the raffinate separator is fed into the lower inlet of the extraction tower, which on the one hand increases the concentration of hydrogen peroxide collected from the bottom of the extraction tower, and on the other hand the concentration gradient of the extraction tower gradually rises, thereby gradually increasing the content of hydrogen peroxide in the working solution at the top of the extraction tower, so that the concentration of hydrogen peroxide collected from the bottom of the raffinate separator gradually rises and gradually increases to above 27.5%.

[0051] In Example 4, when the content of hydrogen peroxide entrained by the working solution discharged from the top of the raffinate separator rises, the packing layer pure water flow rate of the raffinate separator needs to be appropriately increased by 0-2 m 3 / h, which will cause the concentration of hydrogen peroxide collected from the bottom of the raffinate separator to further decrease. When the concentration is below 15%, the hydrogen peroxide discharged from the bottom of the raffinate separator is fed into the upper inlet of the extraction tower, which on the one hand increases the concentration gradient of the extraction tower, thereby gradually increasing the content of hydrogen peroxide in the working solution at the top of the extraction tower, so that the concentration of hydrogen peroxide collected from the bottom of the raffinate separator gradually rises and gradually increases to above 15%.

[0052] If the gradient reuse after the raffinate discharge is not carried out, in order to reach the 50% hydrogen peroxide concentration, the extraction tower setting height needs to be increased to 1.7 times of the present application, and the separation difficulty of the low-concentration hydrogen peroxide at the top of the extraction tower is obviously increased, and more separation times are needed to realize effective separation, which increases the equipment design and investment on the one hand, and significantly increases the material conveying power cost due to the increase of the tower height, which is not cost-effective on the other hand. The present application utilizes the gradient of the extraction tower and adopts multi-stage separation feeding to extract according to the concentration distribution, thereby improving the extraction concentration of the extraction tower discharge. In addition, the raffinate separator adopts multi-stage different separation methods to ensure that the hydrogen peroxide content of the circulating working liquid is safe and controllable, and the low-concentration hydrogen peroxide recovered by different raffinate separators is added to the corresponding extraction tower sieve plate according to the concentration gradient, which can increase the total amount of hydrogen peroxide in the extraction tower without increasing the load of the extraction tower.

Claims

1. An extraction apparatus for producing hydrogen peroxide using the anthraquinone process, the apparatus comprising an extraction tower, characterized in that: The extraction tower has a high-concentration hydrogen peroxide outlet at the bottom, a feed inlet at the bottom, and a water inlet at the top. The top of the extraction tower has a raffinate outlet, which is connected to a raffinate separator via a pipeline. The raffinate separator has a light phase outlet at the top and a heavy phase outlet at the bottom. The heavy phase outlet is connected to multiple outlet pipelines depending on the hydrogen peroxide concentration. The outlet pipeline with the lowest hydrogen peroxide concentration is connected to the extraction tower's return port. The return port is located between the extraction tower's feed inlet and water inlet. Multiple return ports are provided, with the heavy phase outlet of the raffinate separator connected to different return ports via different outlet pipelines. The lower the hydrogen peroxide concentration, the higher the corresponding return port is located. The specific extraction steps are as follows: S1. The working solution containing hydrogen peroxide enters from the feed inlet of the extraction tower. Pure water at 50~60℃ enters the upper part of the extraction tower through the water inlet. The hydrogen peroxide in the working solution is extracted by countercurrent extraction of pure water. The top discharge is the working solution containing low concentration of hydrogen peroxide, which enters the raffinate separator. 45~50% hydrogen peroxide is collected from the high concentration hydrogen peroxide outlet at the bottom of the extraction tower. S2. The material in the raffinate separator is first initially separated by inclined plate sedimentation. The settled hydrogen peroxide heavy phase enters the coalescing collector. Water is added to the working fluid and it enters the packing layer for further extraction. The extracted hydrogen peroxide enters the coalescing collector. The working fluid is then separated by coalescing to control the hydrogen peroxide content to below 0.1 g / L and is collected as the light phase. The heavy phase output from the bottom of the raffinate separator is hydrogen peroxide of a certain concentration. The output is controlled according to the hydrogen peroxide concentration, or it is returned to the extraction tower for re-extraction.

2. The apparatus according to claim 1, characterized in that: The extraction tower has two return ports at different heights between the feed inlet and the water inlet. The outlet pipe with a hydrogen peroxide concentration of less than 15 wt% is connected to the upper return port, and the outlet pipe with a hydrogen peroxide concentration of 15~27.5 wt% is connected to the lower return port. After the heavy phase outlet, there is also a collection outlet pipe with a hydrogen peroxide concentration of more than 27.5 wt%.

3. The apparatus according to claim 1, characterized in that: The top of the extraction tower is equipped with a nitrogen inlet pipe, an vent pipe, and a vent valve. It is also equipped with a pressure sensor, and an oxygen concentration detection device is installed on the vent pipe. An overflow line is also installed above the outlet of the residual phase of the extraction tower.

4. The apparatus according to claim 1, characterized in that: The raffinate separator is divided into three stages longitudinally along the flow direction of the working fluid: the inclined plate sedimentation separation zone, the packing layer separation zone, and the coalescing collector separation zone.

5. The apparatus according to claim 1, characterized in that: Temperature sensors are installed in the upper, middle and lower sections of the extraction tower, and an emergency discharge valve is installed at the bottom of the extraction tower. The thermometers in the upper, middle and lower sections of the extraction tower are interlocked with the emergency discharge valve.

6. The apparatus according to claim 1, characterized in that: Temperature sensors are installed at the inlet, outlet, and outlet of the raffinate separator. An emergency discharge valve is also installed on the outlet pipe after the heavy phase outlet. The thermometers at the inlet, outlet, and outlet of the raffinate separator are interlocked with the emergency discharge valve.

7. The apparatus according to claim 1, characterized in that: When the concentration of the heavy phase discharge from the bottom of the raffinate separator is higher than 27.5%, it is collected as the finished product. When the concentration is between 15% and 27.5%, it is returned to the lower part of the extraction tower for extraction again. When the concentration is lower than 15%, it is returned to the upper part of the extraction tower for extraction again.

8. The apparatus according to claim 1, characterized in that: Three temperature sensors are installed at the top, middle, and bottom of the same layer of the extraction tower. When two of the three temperatures at any layer are ≥55℃ with a temperature rise rate ≥2℃ / min, and / or the temperature is ≥60℃, the material is discharged through the bottom of the extraction tower. Three temperature sensors are installed at the front, middle, and rear of the raffinate separator. When two of the three temperatures at any location are ≥55℃ with a temperature rise rate ≥2℃ / min, and / or the temperature is ≥60℃, the material is discharged through the heavy phase outlet pipe and the emergency discharge valve.

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