Hydrogen peroxide concentration system

Abstract

The present invention provides a hydrogen peroxide concentration system, comprising a distillation device, a first heat exchanger, and a heat-supply heat pump device, the first heat exchanger being used for hydrogen peroxide concentration. The first heat exchanger comprises a first channel and a second channel; the heat-supply heat pump device comprises a first heat exchange loop, and a first heat exchange medium is circulated in the first heat exchange loop; a heat transfer medium storage component, a compressor, and a second heat exchanger are arranged on the first heat exchange loop, and the second heat exchanger is arranged between the heat transfer medium storage component and the compressor; the distillation device is connected to the second heat exchanger; and the first heat exchange medium is configured to provide heat to the first heat exchanger, and the second heat exchanger is configured to enable steam discharged from the distillation device to exchange heat with the first heat exchange medium. The system re-gasifies a steam condensate by means of a cyclic compression use of a heat transfer medium, providing a heat source for hydrogen peroxide concentration, thereby reducing the production cost of a hydrogen peroxide concentration process.

Description

A hydrogen peroxide concentration system Technical Field

[0001] This invention belongs to the field of hydrogen peroxide production technology, and in particular relates to a hydrogen peroxide concentration system. Background Technology

[0002] Propylene oxide (PO) is the second largest downstream derivative of propylene in terms of production capacity after polypropylene. It is widely used in the production of many high-value-added chemicals such as propylene glycol, propylene carbonate, polyurethane, and unsaturated resins, playing an irreplaceable role in transportation electronics, construction furniture, daily chemicals, and pharmaceuticals. In recent years, with the continuous improvement of human production and living standards, the consumption of PO has shown a year-on-year increasing trend. PO preparation methods include the co-oxidation route using organic peroxides as oxidants and the hydrogen peroxide method for preparing propylene oxide (HPPO). Among these, the HPPO process has advantages such as high atom utilization, cleanliness, high efficiency, and simple process, and occupies an important position in propylene oxide production.

[0003] Propylene oxide can be efficiently synthesized via a one-step process using hydrogen peroxide and propylene (HPPO method). Hydrogen peroxide is a clean oxidant that can be used as an oxidant, bleaching agent, disinfectant, and in the production of inorganic and organic peroxides, as well as in medical chemical analysis processes. With the increasing demand for PO, the demand for high-concentration hydrogen peroxide is also continuously increasing; however, existing hydrogen peroxide plants mainly use fresh steam as the heat source for the distillation column and falling film evaporator, which suffers from drawbacks such as high energy consumption, low thermal efficiency, and high production costs. Summary of the Invention

[0004] In view of this, the present invention aims to propose a hydrogen peroxide concentration system that, through the cyclic compression and utilization of the heat extraction medium, re-vaporizes the steam condensate to provide a heat source for hydrogen peroxide concentration. The purpose of this invention is to use electricity instead of fresh steam, significantly reducing energy consumption and saving production costs in the hydrogen peroxide concentration process.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0006] A hydrogen peroxide concentration system includes a distillation unit, a first heat exchanger, and a heat supply heat pump unit, wherein the first heat exchanger is used for hydrogen peroxide concentration.

[0007] The first heat exchanger includes a first channel and a second channel. Hydrogen peroxide flows through the first channel, and a heat exchange medium capable of exchanging heat with the hydrogen peroxide flows through the second channel.

[0008] The heat supply heat pump device includes a first heat exchange circuit in which a first heat exchange medium flows. The first heat exchange circuit is equipped with a heat-extracting working fluid storage component, a compressor, and a second heat exchanger. The heat-extracting working fluid storage component can store the first heat exchange medium. The second heat exchanger is disposed between the heat-extracting working fluid storage component and the compressor. The distillation device is connected to the second heat exchanger.

[0009] The first heat exchange medium is configured to provide heat to the first heat exchanger, so that the water in the hydrogen peroxide in the first channel is converted into steam and introduced into the distillation device, thereby concentrating the hydrogen peroxide.

[0010] The second heat exchanger is configured to allow the steam discharged from the distillation unit to exchange heat with the first heat exchange medium, so that the first heat exchange medium evaporates back into the compressor.

[0011] Furthermore, the first heat exchange circuit is connected to the second channel, one end of the second channel is connected to the exhaust port of the compressor, and the other end of the second channel is connected to the heat extraction working fluid storage component.

[0012] Furthermore, a third heat exchanger is also provided on the first heat exchange circuit, and the third heat exchanger is located between the exhaust port of the compressor and the heat extraction working fluid storage component.

[0013] The heat supply heat pump device further includes a second heat exchange circuit, in which a second heat exchange medium flows, and the third heat exchanger and a steam condensate tank are provided on the second heat exchange circuit.

[0014] The second channel is connected to the second heat exchange circuit, one end of the second channel is connected to the third heat exchanger, and the other end of the second channel is connected to the steam condensate tank;

[0015] The third heat exchanger is configured to enable the first heat exchange medium and the second heat exchange medium to exchange heat, thereby providing heat to the first heat exchanger.

[0016] Furthermore, the second heat exchanger is connected to the steam condensate tank, and the liquid after the steam discharged from the distillation unit is heated by the second heat exchanger enters the steam condensate tank.

[0017] Furthermore, it also includes a vacuum pump, through which the non-condensable gas from the distillation unit after heat exchange in the second heat exchanger and the non-condensable gas from the first heat exchanger are extracted.

[0018] Furthermore, it also includes a vacuum pump, through which the non-condensable gas after heat exchange in the distillation unit via the second heat exchanger is extracted.

[0019] Furthermore, it also includes a liquid level control branch connected to the first channel, wherein a liquid level control valve is provided on the liquid level control branch, and the liquid level control valve is configured to control the amount of hydrogen peroxide in the first channel by adjusting the feed rate of dilute hydrogen peroxide; and / or it also includes a temperature control branch connected to the first channel, wherein a temperature control valve is provided on the temperature control branch, and the temperature control valve is configured to control the temperature of hydrogen peroxide in the first channel by adjusting the discharge rate of concentrated hydrogen peroxide.

[0020] Furthermore, it also includes a pressure regulating branch, the two ends of which are connected to both sides of the vacuum pump. The pressure regulating branch is configured to control the pressure and temperature of the top section of the distillation unit by controlling the vacuum pump; and / or the pressure range of the top section of the distillation unit is 6 to 10 kPaA and the temperature is 36 to 46°C.

[0021] Furthermore, the temperature of the hydrogen peroxide in the first channel is 55–65°C and the pressure is 8–12 kPaA; and / or the temperature of the steam generated in the second channel is 65–75°C and the pressure is 25–35 kPaA.

[0022] Furthermore, the condensation temperature of the first heat exchange medium is 75-85°C, and the evaporation temperature is 25-35°C; preferably, the first heat exchange medium includes one or more of n-butane, isobutane, R134a, R245fa, ammonia, and propylene.

[0023] Compared with existing technologies, the hydrogen peroxide concentration system of the present invention has the following advantages:

[0024] The hydrogen peroxide concentration system described in this invention utilizes the cyclic compression and reuse of the heat-extracting working fluid to re-vaporize the steam condensate, providing a heat source for hydrogen peroxide concentration. The purpose of this invention is to use electricity instead of fresh steam, significantly reducing energy consumption and saving production costs in the hydrogen peroxide concentration process. Attached Figure Description

[0025] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0026] Figure 1 is a schematic diagram of the hydrogen peroxide concentration system according to Embodiment 1 of the present invention;

[0027] Figure 2 is a schematic diagram of the hydrogen peroxide concentration system described in Embodiment 2 of the present invention;

[0028] Figure 3 is a schematic diagram of the hydrogen peroxide concentration system described in Comparative Example 1 of the present invention.

[0029] Explanation of reference numerals in the attached drawings: 1. Distillation column; 2. Falling film evaporator; 3. Hydrogen peroxide circulating pump; 4. Steam condensate tank; 5. Condenser; 6. Steam condensate feed pump; 7. Heat extraction medium storage tank; 8. Evaporator; 9. Vacuum pump; 10. Compressor; 11. Gas-liquid separation component; 12. Steam ejector; 13. Top condenser. Detailed Implementation

[0030] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0031] In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "top," "bottom," "inner," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0032] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] In the following embodiments, the distillation apparatus is such as a distillation column 1, the first heat exchanger is such as a falling film evaporator 2, the heat extraction medium storage component is such as a heat extraction medium storage tank 7, the second heat exchanger is such as an evaporator 8, and the third heat exchanger is such as a condenser 5. However, these embodiments are not limited to these embodiments, provided that the purpose of this invention is achieved.

[0035] Example 1

[0036] As shown in Figure 1, a hydrogen peroxide concentration system includes a distillation column 1, a falling film evaporator 2, a heat supply heat pump device, and a vacuum pump 9.

[0037] The falling film evaporator 2 is used for hydrogen peroxide concentration and includes a first channel and a second channel. Hydrogen peroxide flows through the first channel, and a heat exchange medium capable of exchanging heat with the hydrogen peroxide flows through the second channel.

[0038] The heat supply heat pump device includes a first heat exchange circuit in which a first heat exchange medium flows. The first heat exchange circuit is equipped with a heat exchange medium storage tank 7, a compressor 10, and an evaporator 8. The heat exchange medium storage tank 7 can store the first heat exchange medium. The evaporator 8 is located between the heat exchange medium storage tank 7 and the compressor 10. A distillation column 1 is connected to the evaporator 8. As shown in Figure 1, the first heat exchange circuit is also connected to a second channel. One end of the second channel is connected to the exhaust port of the compressor 10, and the other end of the second channel is connected to the heat exchange medium storage tank 7. Those skilled in the art will understand that the specific structure of the heat exchange medium storage tank 7 is not limiting, as long as it can store the heat exchange medium so that it circulates within the first heat exchange circuit, ensuring the supply of the heat exchange medium.

[0039] The first heat exchange medium is configured to provide heat to the falling film evaporator 2 so that the water in the hydrogen peroxide in the first channel is turned into steam and passed into the distillation column 1 to achieve the concentration of hydrogen peroxide; the evaporator 8 is configured to allow the steam discharged from the distillation column 1 to exchange heat with the first heat exchange medium so that the first heat exchange medium evaporates back into the compressor 10.

[0040] The non-condensable gas after heat exchange in the distillation column 1 via the evaporator 8 is extracted by the vacuum pump 9; the two sides of the vacuum pump 9 are also connected to the two ends of a pressure regulating branch, which is configured to control the pressure and temperature of the top part of the distillation column 1 by controlling the vacuum pump 9; and / or the pressure range of the top part of the distillation column 1 is 6 to 10 kPaA and the temperature is 36 to 46°C.

[0041] The first channel is also provided with a liquid level control branch connected thereto, and a liquid level control valve is provided on the liquid level control branch. The liquid level control valve is configured to control the amount of hydrogen peroxide in the first channel by adjusting the feed rate of dilute hydrogen peroxide. The first channel is also provided with a temperature control branch connected thereto, and a temperature control valve is provided on the temperature control branch. The temperature control valve is configured to control the temperature of hydrogen peroxide in the first channel by adjusting the discharge rate of concentrated hydrogen peroxide.

[0042] The temperature of the hydrogen peroxide in the first channel is 55-65℃, and the pressure is 8-12 kPaA.

[0043] The condensation temperature of the first heat exchange medium is 75–85°C, and the evaporation temperature is 25–35°C. Preferably, the first heat exchange medium can be one or more of n-butane, isobutane, R134a, R245fa, ammonia, and propylene. It should be noted that this application does not impose any restrictions on the specific type of the first heat exchange medium, as long as its condensation temperature is 75–85°C and its evaporation temperature is 25–35°C, i.e., it can meet the heat supply requirements of the hydrogen peroxide in the first channel of the falling film heat exchanger 2, it is acceptable. Those skilled in the art can set this according to actual conditions.

[0044] The compressor 10 is equipped with a flow meter at its outlet to detect the amount of heat exchange medium condensed in the condenser 5. The compressor 10 is driven by a motor. A pressure control valve and a return valve are installed at the inlet of the compressor 10. The temperature, pressure, and flow rate of the heat exchange medium at the outlet of the compressor 10 are adjusted by regulating the inlet pressure control valve and the return valve. It should be noted that the compressor 10 can be a variable frequency compressor or a fixed frequency compressor; the number of compressors 10 can be one or more; multiple compressors 10 can be used in series or in parallel. That is, any adjustment to the compressor frequency and the heat supply of the first heat exchange circuit by changing the type, number, or connection method of the compressors 10 does not deviate from the basic principles of this application and falls within the protection scope of this application.

[0045] The compressor 10 is also connected to the gas-liquid separation component 11. The specific structure of the gas-liquid separation component 11 is not restrictive, as long as it can prevent the liquid heat exchange medium from entering the compressor 10.

[0046] Working principle:

[0047] The heat-extracting medium evaporates in evaporator 8, enters the gas-liquid separation component 11 for separation, and then enters compressor 10 for compression. The heat-extracting medium at the outlet of compressor 10 directly enters the second channel of falling film evaporator 2 to exchange heat with hydrogen peroxide in the first channel. Steam is generated in the first channel of falling film evaporator 2 and enters distillation column 1. The heat-extracting medium after heat exchange enters heat-extracting medium storage tank 7 and then enters evaporator 8. Falling film evaporator 2 is equipped with hydrogen peroxide circulation pump 3, with dilute hydrogen peroxide feed and concentrated hydrogen peroxide discharge on the circulation pipeline. Pure water is fed to the top of distillation column 1, concentrated hydrogen peroxide is collected from the bottom of the column, and water vapor collected from the top of the column enters evaporator 8. After condensation, the liquid enters steam condensate tank 4, and non-condensable gases are discharged through vacuum pump 9.

[0048] The results show that the power consumption for producing one ton of concentrated hydrogen peroxide is 240-260 kW. At an electricity price of 0.5 yuan / kWh, the energy cost for producing one ton of concentrated hydrogen peroxide is 120-130 yuan. Compared with existing hydrogen peroxide concentration devices on the market that use fresh steam as a heat source, the energy cost for producing one ton of concentrated hydrogen peroxide is reduced by about 32%-34%.

[0049] Example 2

[0050] As shown in Figure 2, a hydrogen peroxide concentration system includes a distillation column 1, a falling film evaporator 2, a heat supply heat pump device, a condenser 5, and a vacuum pump 9.

[0051] The falling film evaporator 2 is used for hydrogen peroxide concentration and includes a first channel and a second channel. Hydrogen peroxide flows through the first channel, and a heat exchange medium capable of exchanging heat with the hydrogen peroxide flows through the second channel.

[0052] The heat supply heat pump device includes a first heat exchange circuit in which a first heat exchange medium flows. The first heat exchange circuit is equipped with a heat exchange medium storage tank 7, a compressor 10, and an evaporator 8. The heat exchange medium storage tank 7 can store the first heat exchange medium. The evaporator 8 is located between the heat exchange medium storage tank 7 and the compressor 10. The distillation column 1 is connected to the evaporator 8. The pressure drop of water vapor in the evaporator 8 must be less than 3 kPa. The heat exchanger type of the evaporator 8 can be BXM, BKU, BKM, falling film evaporator, etc.

[0053] A condenser 5 is also provided on the first heat exchange circuit, and the condenser 5 is located between the exhaust port of the compressor 10 and the heat exchange medium storage tank 7; the heat supply heat pump device also includes a second heat exchange circuit, in which a second heat exchange medium flows, and a condenser 5 and a steam condensate tank 4 are provided on the second heat exchange circuit; a second channel is connected to the second heat exchange circuit, one end of the second channel is connected to the condenser 5, and the other end of the second channel is connected to the steam condensate tank 4; the condenser 5 is configured to enable heat exchange between the first heat exchange medium and the second heat exchange medium to provide heat to the first heat exchanger. The evaporator 8 is connected to the steam condensate tank 4, and the liquid after heat exchange of the steam discharged from the distillation column 1 by the evaporator 8 enters the steam condensate tank 4. The first heat exchange medium is configured to provide heat to the falling film evaporator 2, so that the water in the hydrogen peroxide in the first channel is converted into steam and fed into the distillation column 1 to concentrate the hydrogen peroxide. In this specific embodiment, the heat of the first heat exchange medium is transferred to the second heat exchange circuit through the condenser 5. The second heat exchange circuit transfers the heat to the second channel of the falling film evaporator 2, so that the water in the first channel evaporates and concentrates the hydrogen peroxide. The evaporator 8 is configured to allow the steam discharged from the distillation column 1 to exchange heat with the first heat exchange medium, so that the first heat exchange medium evaporates back into the compressor 10. The pressure drop of the water vapor in the condenser 5 must be less than 5 kPa. The heat exchanger type of the condenser 5 can be BXM, BKU, BKM, or a falling film evaporator.

[0054] The non-condensable gas after heat exchange in the distillation column 1 via the evaporator 8 and the non-condensable gas in the falling film evaporator is extracted by the vacuum pump 9. The two sides of the vacuum pump 9 are also connected to the two ends of a pressure regulating branch. The pressure regulating branch is configured to control the pressure and temperature of the top part of the distillation column 1 by controlling the vacuum pump 9. The pressure range of the top part of the distillation column 1 is 6-10 kPaA and the temperature is 36-46℃.

[0055] The first channel is also provided with a liquid level control branch connected thereto, and a liquid level control valve is provided on the liquid level control branch. The liquid level control valve is configured to control the amount of hydrogen peroxide in the first channel by adjusting the feed rate of dilute hydrogen peroxide. The first channel is also provided with a temperature control branch connected thereto, and a temperature control valve is provided on the temperature control branch. The temperature control valve is configured to control the temperature of hydrogen peroxide in the first channel by adjusting the discharge rate of concentrated hydrogen peroxide.

[0056] The hydrogen peroxide temperature in the first channel is 55–65°C and the pressure is 8–12 kPaA; and / or the steam generated in the second channel has a temperature of 65–75°C and a pressure of 25–35 kPaA.

[0057] The condensation temperature of the first heat exchange medium is 75–85°C, and the evaporation temperature is 25–35°C. Preferably, the first heat exchange medium can be one or more of n-butane, isobutane, R134a, R245fa, ammonia, and propylene, but it is not limited to these. As long as the condensation temperature of the first heat exchange medium is 75–85°C and the evaporation temperature is 25–35°C, that is, it can meet the heat supply requirements of hydrogen peroxide in the first channel of the falling film heat exchanger 2, it is acceptable. Those skilled in the art can set it according to actual conditions. In this specific embodiment, the second heat exchange medium is water. Of course, the specific type of the second heat exchange medium is not limiting, and those skilled in the art can set it according to actual conditions.

[0058] The compressor 10 is equipped with a flow meter at its outlet to detect the amount of heat exchange medium condensed in the condenser 5. The compressor 10 is driven by a motor. The compressor 10 is equipped with a pressure control valve at its inlet and a reflux valve. The temperature, pressure and flow rate of the heat exchange medium at the outlet of the compressor 10 are adjusted by regulating the pressure control valve at the inlet of the compressor 10 and the reflux valve.

[0059] The compressor 10 is also connected to the gas-liquid separation component 11.

[0060] Working principle:

[0061] The heat-extracting medium evaporates in evaporator 8, enters the gas-liquid separation component 11 for separation, and then enters the compressor 10 for compression. The compressed heat-extracting medium enters the condenser 5 for condensation, then enters the heat-extracting medium storage tank 7, and then enters the evaporator 8 for further evaporation. The steam condensate is sent to the condenser 5 by the steam condensate feed pump 6 for vaporization, and then enters the second channel of the falling film evaporator 2 to provide a heat source. After condensation, it enters the steam condensate tank 4. The falling film evaporator 2 is equipped with a hydrogen peroxide circulation pump 3, with a dilute hydrogen peroxide feed and a concentrated hydrogen peroxide discharge on the circulation pipeline. Steam is generated in the first channel of the falling film evaporator 2 and enters the distillation column 1. Pure water is fed to the top of the distillation column 1, concentrated hydrogen peroxide is collected from the bottom of the column, and water vapor collected from the top of the column enters the evaporator 8. After condensation, it enters the steam condensate tank 4. The non-condensable gas condensed in the distillation column 1 by the evaporator 8 and the non-condensable gas in the second channel of the falling film evaporator 2 are discharged by the vacuum pump 9.

[0062] The results show that the power consumption for producing one ton of concentrated hydrogen peroxide is 255-270 kW. At an electricity price of 0.5 yuan / kWh, the energy cost for producing one ton of concentrated hydrogen peroxide is 127.5-135 yuan. Compared with existing hydrogen peroxide concentration devices on the market that use fresh steam as a heat source, the energy cost for producing one ton of concentrated hydrogen peroxide is reduced by about 28%-32%.

[0063] Comparative Example 1

[0064] As shown in Figure 3, a hydrogen peroxide concentration system includes a distillation column 1, a falling film evaporator 2, a steam condensate tank 4, a vacuum pump 9, a steam ejector 12, and a top condenser 13. The bottom hydrogen peroxide outlet of the falling film evaporator 2 is connected to the top hydrogen peroxide inlet of the falling film evaporator 2 via a circulation pipeline. The circulation pipeline is equipped with a dilute hydrogen peroxide inlet and a concentrated hydrogen peroxide outlet, and a hydrogen peroxide circulation pump 3 is also installed on the circulation pipeline. The steam generated in the first channel of the falling film evaporator 2 enters the distillation column 1. The top steam outlet of the distillation column 1 is connected to the inlet of the steam ejector 12. Fresh steam enters the steam ejector 12, mixes with the overhead steam of the distillation column 1, and then enters the steam inlet of the falling film evaporator 2. The condensate outlet of the falling film evaporator 2 is connected to the steam condensate tank 4. The steam outlet at the top of the distillation column 1 is connected to the top condenser 13. The overhead steam of the distillation column 1 exchanges heat with the circulating cooling water in the top condenser 13. The top condenser 13 is also connected to the steam condensate tank 4. After the overhead steam of the distillation column 1 is condensed, it enters the steam condensate tank 4. The non-condensable gas at the top of the distillation column 1 and the non-condensable gas in the second channel of the falling film evaporator 2 are discharged through the vacuum pump 9.

[0065] The distillation column 1 is also equipped with a pressure gauge, and the pressure range of the distillation column 1 is controlled to be 6-10 kPaA and the pressure temperature is 36-46℃ by adjusting the bypass pressure regulating valve of the vacuum pump 9.

[0066] The bottom of the falling film evaporator 2 is also equipped with a liquid level control circuit. A liquid level control valve for the falling film evaporator is installed at the inlet of the rare hydrogen peroxide, and the hydrogen peroxide liquid level is controlled by adjusting the feed rate of the rare hydrogen peroxide. The bottom of the falling film evaporator 2 is also equipped with a temperature control circuit. A temperature control valve for the falling film evaporator is installed at the outlet of the concentrated hydrogen peroxide, and the temperature of the hydrogen peroxide is controlled by adjusting the discharge rate of the concentrated hydrogen peroxide.

[0067] In falling film evaporator 2, the temperature of hydrogen peroxide is 55-65℃ and the pressure is 8-12 kPaA; in falling film evaporator 82, the temperature of water vapor is 65-75℃ and the pressure is 25-35 kPaA.

[0068] The pressure drop of water vapor in the condenser at the top of the tower must be less than 3 kPa.

[0069] Working principle:

[0070] Fresh steam mixes with the steam at the top of distillation column 1 via steam ejector 12 and enters the second channel of falling film evaporator 2 to exchange heat with the hydrogen peroxide in the first channel. After condensation, the steam enters the steam condensate tank 4. Falling film evaporator 2 is equipped with a hydrogen peroxide circulation pump 3, with a dilute hydrogen peroxide feed and a concentrated hydrogen peroxide discharge on the circulation pipeline. Steam generated in the first channel of falling film evaporator 2 enters distillation column 1. Pure water is fed to the top of distillation column 1, concentrated hydrogen peroxide is collected from the bottom, and water vapor collected from the top enters the top condenser 13 to exchange heat with circulating cooling water. After condensation, the steam enters the steam condensate tank 4. Non-condensable gases generated at the top of distillation column 1 and in the second channel of falling film evaporator 2 are discharged via vacuum pump 9.

[0071] The results showed that the fresh steam consumption for producing one ton of concentrated hydrogen peroxide was 0.8 to 0.9 tons. Based on a fresh steam price of 220 yuan / ton, the energy cost for producing one ton of concentrated hydrogen peroxide was 176 to 198 yuan.

[0072] By comparing the comparative examples and the embodiments, it can be seen that the hydrogen peroxide concentration system of the present invention can significantly reduce energy consumption and save production costs in the hydrogen peroxide concentration process.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hydrogen peroxide concentration system, characterized by: The device comprises a rectifying device, a first heat exchanger for concentrating hydrogen peroxide, and a heat supply heat pump device. The first heat exchanger comprises a first channel and a second channel, the first channel flows with hydrogen peroxide, and the second channel flows with a heat exchange medium capable of exchanging heat with hydrogen peroxide. The heat supply heat pump device comprises a first heat exchange circuit, the first heat exchange circuit flows with a first heat exchange medium, the first heat exchange circuit is provided with a heat extraction working medium storage component, a compressor, and a second heat exchanger, the heat extraction working medium storage component is capable of storing the first heat exchange medium, the second heat exchanger is arranged between the heat extraction working medium storage component and the compressor, and the rectifying device is connected with the second heat exchanger. The first heat exchange medium is arranged to provide heat for the first heat exchanger, so that the water in the hydrogen peroxide in the first channel becomes steam and enters the rectifying device, thereby realizing the concentration of hydrogen peroxide. The second heat exchanger is arranged to exchange heat between the steam discharged from the rectifying device and the first heat exchange medium, so that the first heat exchange medium evaporates back into the compressor.

2. The hydrogen peroxide concentration system of claim 1, wherein: The first heat exchange circuit is connected with the second channel, one end of the second channel is connected with the exhaust port of the compressor, and the other end of the second channel is connected with the heat extraction working medium storage component.

3. The hydrogen peroxide concentration system of claim 1, wherein: The first heat exchange circuit is further provided with a third heat exchanger, which is arranged between the exhaust port of the compressor and the heat extraction working medium storage component. The heat supply heat pump device further comprises a second heat exchange circuit, the second heat exchange circuit flows with a second heat exchange medium, and the second heat exchange circuit is provided with the third heat exchanger and a steam condensate tank. The second channel is connected with the second heat exchange circuit, one end of the second channel is connected with the third heat exchanger, and the other end of the second channel is connected with the steam condensate tank. The third heat exchanger is arranged to exchange heat between the first heat exchange medium and the second heat exchange medium, so as to provide heat for the first heat exchanger.

4. The hydrogen peroxide concentration system of claim 3, wherein: The second heat exchanger is connected with the steam condensate tank, and the liquid of the steam discharged from the rectifying device after heat exchange in the second heat exchanger enters the steam condensate tank.

5. The hydrogen peroxide concentration system of claim 3, wherein: A vacuum pump is further included, and the non-condensable gas after heat exchange in the rectifying device through the second heat exchanger and the non-condensable gas of the first heat exchanger are extracted by the vacuum pump.

6. The hydrogen peroxide concentration system of claim 2, wherein: A vacuum pump is further included, and the non-condensable gas after heat exchange in the rectifying device through the second heat exchanger is extracted by the vacuum pump.

7. The hydrogen peroxide concentration system of claim 1, wherein: A liquid level control branch connected with the first channel is further included, a liquid level control valve is arranged on the liquid level control branch, the liquid level control valve is arranged to control the amount of hydrogen peroxide in the first channel by adjusting the amount of dilute hydrogen peroxide feed; and / or a temperature control branch connected with the first channel is further included, a temperature control valve is arranged on the temperature control branch, and the temperature control valve is arranged to control the temperature of hydrogen peroxide in the first channel by adjusting the amount of concentrated hydrogen peroxide discharge.

8. The hydrogen peroxide concentration system of claim 5 or 6, wherein: The pressure regulating branch is connected at both ends to both sides of the vacuum pump, and is configured to control the pressure and temperature of the overhead part of the rectifying device by controlling the vacuum pump; and / or the pressure of the overhead part of the rectifying device is in the range of 6-10 kPaA, and the temperature is in the range of 36-46℃.

9. The hydrogen peroxide concentration system according to any one of claims 1 to 7, characterized in that: The temperature of the hydrogen peroxide in the first channel is in the range of 55-65℃, and the pressure is in the range of 8-12 kPaA; and / or the temperature of the steam generated in the second channel is in the range of 65-75℃, and the pressure is in the range of 25-35 kPaA.

10. The hydrogen peroxide concentration system of any one of claims 1 to 7, wherein: The condensation temperature of the first heat exchange medium is in the range of 75-85℃, and the evaporation temperature is in the range of 25-35℃; preferably, the first heat exchange medium comprises one or more of n-butane, isobutane, R134a, R245fa, ammonia, and propylene.

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