Counter-current oxidation device and process for producing hydrogen peroxide

Abstract

The invention discloses a counter-current oxidation device and process for producing hydrogen peroxide. The counter-current oxidation device comprises a counter-current oxidation tower, an oxidation tail gas treatment procedure, an oxidation liquid tank, an oxygen content on-line measurement assembly and an analysis treatment unit. The oxidation device provided by the invention can reduce the phenomena of entrainment of a gas phase to a product, entrainment of gas in an oxidation liquid and the like, and part of the gas phase enters the tower in a microbubble manner, so that the gas-liquid two-phase reaction is more sufficient; and the safety of the oxidation liquid tank is ensured and the use amount of fresh nitrogen is reduced through the online measurement system and the analysis processing system, so that the production capacity, safety and economical efficiency of the whole device are improved.

Description

Technical Field

[0001] The present invention relates to a device and process for gas-liquid two-phase countercurrent contact reaction, and in particular to a countercurrent oxidation device and process for producing hydrogen peroxide. Background Art

[0002] Currently, the anthraquinone process is the primary method for producing hydrogen peroxide both domestically and internationally. This process uses alkylanthraquinone (AQ, primarily 2-alkylanthraquinone) as a carrier. A suitable solvent for dissolving anthraquinone and anthrahydroquinone, along with a pH-adjusting agent, forms a working fluid. The entire preparation process generally includes hydrogenation, oxidation, extraction, and post-treatment. The solvent for dissolving anthraquinone is typically heavy aromatic hydrocarbons extracted from the petroleum industry, with C9 or C10 aromatics being the most common industrially used. In the hydrogenation process, anthraquinone is hydrogenated over a catalyst to form anthrahydroquinone, transforming the working fluid into a hydrogenated solution. In the oxidation process, the anthrahydroquinone in the hydrogenated solution reacts with oxygen to regenerate anthraquinone and hydrogen peroxide, transforming the hydrogenated solution into an oxidized solution. The oxygen source can be pure oxygen or oxygen-enriched air. In industrial practice, compressed air is often used for cost and safety reasons.

[0003] Domestic oxidation processes often utilize a parallel oxidation process, in which hydrogenated liquid and air flow in parallel and upward. Because the oxygen content in air is only approximately 21%, the reaction pressure in the oxidation tower is 0.18–0.4 MPa, and the reaction temperature is 40–55°C. These relatively mild reaction conditions result in a low oxygen concentration at the gas-liquid interface and a slow reaction rate. Although two or three towers in series are often used in industry to improve conversion rates, these towers are primarily empty, aside from the gas distributor, redistributor, and heat exchanger. Even after extended reaction times in the oxidation tower, the oxidation yield remains only approximately 90–95%, with tail oxygen content at 6% or higher. These factors present disadvantages, including low oxidation yield and high tail oxygen content.

[0004] Manufacturers abroad and in some parts of China have begun adopting countercurrent oxidation processes. Compared to cocurrent oxidation, countercurrent gas-liquid contact improves oxidation yields and reduces tail gas oxygen content. However, this method is more complex to operate, and the nearly fully reacted oxidation liquid is exposed to large amounts of fresh air, causing some products to be carried away by the air or decompose. Fresh air has a high oxygen content, and the oxidizing liquid can carry a small amount of fresh air into the oxidation tank, where it is released after decompression, increasing the oxygen content above the tank and the risk of flash explosions. Summary of the Invention

[0005] The present invention provides a countercurrent oxidation device and process for producing hydrogen peroxide. The device comprises an oxidation tower, an oxidation liquid tank, an online oxygen content measurement assembly, and an analysis and processing unit. The hydrogenated liquid enters the oxidation tower from the top through a liquid distributor and flows downward, while the gas enters the oxidation tower from the bottom through a gas distributor and flows upward, resulting in macroscopic countercurrent contact between the gas and liquid phases. The gas inlet can have one, two, or three inlets. When two or three inlets are used, the main gas inlet is sufficiently far from the oxidation liquid outlet to reduce the amount of gas carried over by the oxidation liquid, reduce the amount of gas entering the main gas inlet to reduce gas entrainment, and reduce the hydrogen peroxide concentration near the main gas inlet to reduce hydrogen peroxide decomposition caused by large amounts of gas. After the oxidation tail gas leaving the top of the tower undergoes a tail gas treatment process to cool most of its components, such as aromatic hydrocarbons, a portion of the treated oxidation tail gas can be connected to the top of the oxidation liquid tank after being determined by the analysis and processing unit. This treated oxidation tail gas replaces the fresh nitrogen that was originally introduced directly into the oxidation liquid tank, ensuring safety during system operation and reducing costs.

[0006] A first aspect of the present invention provides a countercurrent oxidation device for producing hydrogen peroxide, the countercurrent oxidation device comprising a countercurrent oxidation tower 101, an oxidation tail gas treatment process, an oxidation liquid tank 201, an oxygen content online measurement component, and an analysis and processing unit; A gas inlet is provided at the bottom of the countercurrent oxidation tower 101. An oxidation tail gas discharge pipe 122 connected to the oxidation tail gas treatment process is provided at the top of the countercurrent oxidation tower 101. The oxidation tail gas treatment process is provided with a gas pipe 124. The oxidation liquid tank 201 is provided with a nitrogen pipe 231 and an oxidation tail gas feed pipe 221 connected to the gas pipe 124. The oxidation tail gas feed pipe 221 and the nitrogen pipe 231 are respectively provided with a regulating valve A601 and a regulating valve B602. The oxygen content online measurement component includes an oxygen content online measurement component A and an oxygen content online measurement component B. The signal input end of the oxygen content online measurement component A is connected to the gas pipeline 124, and the signal output end is connected to the analysis and processing unit; the signal input end of the oxygen content online measurement component B is connected to the oxidation liquid tank 201, and the signal output end is connected to the analysis and processing unit; the signal output end of the analysis and processing unit is respectively connected to the regulating valve A601 and the regulating valve B602.

[0007] The oxidized tail gas oxygen content 801 and the vented tail gas oxygen content 802 measured in real time by the oxygen content online measurement component A and the oxygen content online measurement component B are transmitted to the analysis and processing unit. The analysis and processing unit processes the oxidized tail gas oxygen content 801 and the vented tail gas oxygen content 802 and determines the output signal A911 and the output signal B912. The output signal A911 and the output signal B912 respectively control the opening of the regulating valve A601 and the regulating valve B602.

[0008] Preferably, the upper part of the countercurrent oxidation tower 101 is provided with a hydrogenation liquid feed pipe 111, and the lower part is provided with an oxidation liquid discharge pipe 112 connected to the oxidation liquid tank 201; the oxidation tail gas utilization device is provided with a gas content online measurement component, the signal input end of the gas content online measurement component is connected to the oxidation liquid discharge pipe 112, and the signal output end is connected to the analysis and processing unit.

[0009] The oxygen content online measurement component A, the oxygen content online measurement component B, and the gas holdup online measurement component transmit the oxidized tail gas oxygen content 801, the vented tail gas oxygen content 802, and the gas holdup 803 in real time to the analysis and processing unit. The analysis and processing unit processes the oxidized tail gas oxygen content 801, the vented tail gas oxygen content 802, and the gas holdup 803 and determines the output signal A911 and the output signal B912. The output signal A911 and the output signal B912 respectively control the opening of the regulating valve A601 and the regulating valve B602.

[0010] The oxidation tail gas treatment process includes a condenser, and the tail gas treatment process is mainly to remove heavy aromatic hydrocarbons carried in the gas phase. The oxidation tail gas coming out of the gas pipeline 124 is vented or further processed.

[0011] Preferably, the number of gas inlets is one, namely, a gas feed pipe A121. A gas distributor A1011 connected to the gas feed pipe A121 and a liquid distributor 1016 connected to the hydrogenated liquid feed pipe 111 are provided inside the countercurrent oxidation tower 101. The hydrogenated liquid from the hydrogenation process enters the countercurrent oxidation tower 101 through the hydrogenated liquid feed pipe 111 and the liquid distributor 1016. The gas phase enters the countercurrent oxidation tower 101 through the gas feed pipe A121 and the gas distributor A1011. The gas and liquid phases react in countercurrent within the tower, and the oxidized liquid obtained by the reaction enters the oxidized liquid tank 201 through the oxidized liquid discharge pipe 112.

[0012] Preferably, the countercurrent oxidation tower 101 is provided with trays 1015 and a gas-liquid separation assembly 1018 at the top. The gas phase carrying some liquid is separated at the top of the countercurrent oxidation tower 101 by the gas-liquid separation assembly 1018. The gas phase then leaves the oxidation tower through the oxidation tail gas discharge pipe 122, and the liquid phase flows back into the tower, mixing with the main liquid phase and flowing downward.

[0013] Preferably, there are multiple gas inlets; more preferably, there are two gas inlets, namely, from top to bottom, gas feed pipe A121 and gas feed pipe B1211. The countercurrent oxidation tower 101 is equipped with a gas distributor A1011 connected to gas feed pipe A121 and a microbubble generator 1012 connected to gas feed pipe B1211. Gas feed pipe A121 serves as the primary gas inlet. Preferably, the distance between gas distributor 1011 and microbubble generator 1012 is 1-4 meters, preferably 1.5-2.5 meters. Preferably, the amount of gas entering microbubble generator 1012 accounts for 5-20% (by volume) of the total gas entering the countercurrent oxidation tower 101. Preferably, the air entering the oxidation tower through microbubble generator 122 is oxygen-enriched air, with an oxygen content of 21%-100%, preferably 24%-27% or 80%-95%.

[0014] It is further preferred that there are three gas inlets: from top to bottom, gas feed pipe A121, gas feed pipe B1211, and gas feed pipe C1212. Inside the countercurrent oxidation tower 101, a gas distributor A1011 connected to gas feed pipe A121, a microbubble generator 1012 connected to gas feed pipe B1211, and a gas distributor C1013 connected to gas feed pipe C1212 are provided. Gas feed pipe A121 serves as the primary gas inlet. Preferably, the distance between gas distributor A1011 and microbubble generator 1012 is 1-4 m, preferably 1.5-2.5 m. Preferably, the amount of gas entering microbubble generator 1012 accounts for 5-20% (by volume) of the total gas entering the countercurrent oxidation tower 101; and the amount of gas entering the countercurrent oxidation tower 101 through gas distributor C1013 accounts for 10-25% (by volume) of the total gas entering the oxidation tower 101. The height interval between the gas distributor C1013 and the microbubble generator 1012 is 5 cm to 50 cm.

[0015] A second aspect of the present invention provides a countercurrent oxidation process for producing hydrogen peroxide, comprising the following steps: (1) The oxygen content online measurement component A, the oxygen content online measurement component B, and the optional gas holdup online measurement component measure the oxidation tail gas oxygen content 801, the venting tail gas oxygen content 802, and the gas holdup 803 in real time and transmit them to the analysis and processing unit; (2) The analysis and processing unit processes the oxidation tail gas oxygen content 801, the venting tail gas oxygen content 802, and the gas holdup 803 to obtain an intermediate signal A901, an intermediate signal B902, and an intermediate signal C903; (3) The analysis and processing unit determines the output signals A911 and B912 according to the magnitudes of the intermediate signals A901, B902, and C903 in accordance with a given method; the output signals A911 and B912 control the openings of the regulating valves A601 and B602, respectively.

[0016] Preferably, when the countercurrent oxidation device is not provided with a gas holdup online measurement component: when the oxygen content 801 of the oxidized tail gas measured by the oxygen content online measurement component A is ≤8%, the intermediate signal A901 value is adjusted to 0; when the oxygen content 801 of the oxidized tail gas is greater than 8%, the intermediate signal A901 value is adjusted to 1; when the oxygen content 802 of the vented tail gas measured by the oxygen content online measurement component B is ≤5%, the intermediate signal B902 value is adjusted to 0; when the oxygen content 802 of the vented tail gas is greater than 5%, the intermediate signal B902 value is adjusted to 1; When the value of the intermediate signal B902 is 0: the output signal A911 and the output signal B912 are both 0; When the value of the intermediate signal B902 is 1: if the value of the intermediate signal A901 is 0, the output signal B912 is 0 and the output signal A911 is 1; otherwise, the output signal B912 is 1 and the output signal A911 is 0; When the output signal A911 is 0, it means that air is not taken in from here, and the control regulating valve A601 is closed; when the output signal A911 is not 0, it means that air is taken in from here, and the control regulating valve A601 is opened; when the output signal B912 is 0, it means that air is not taken in from here, and the control regulating valve B602 is closed; when the output signal B912B is not 0, it means that air is taken in from here, and the control regulating valve B602 is opened.

[0017] Preferably, when the countercurrent oxidation device is provided with a gas holdup online measurement component: when the oxygen content 801 of the oxidation tail gas measured by the oxygen content online measurement component A is ≤8%, the intermediate signal A901 is adjusted to 0, and when the oxygen content 801 of the oxidation tail gas is greater than 8%, the intermediate signal A901 is adjusted to 1; when the oxygen content 802 of the venting tail gas measured by the oxygen content online measurement component B is ≤5%, the intermediate signal B902 is adjusted to 0, and when the oxygen content 802 of the venting tail gas is greater than 5%, the intermediate signal B902 is adjusted to 1; when the gas holdup 803 in the oxidation liquid discharge pipe 112 measured by the gas holdup online measurement component is ≤4%, the intermediate signal C903 is adjusted to 0, and when the gas holdup 803 is greater than 4%, the intermediate signal C903 is adjusted to 1; When the value of the intermediate signal B902 is 0: the output signal A911 and the output signal B912 are both 0; When the value of the intermediate signal B902 is 1: if the intermediate signal A901 and the intermediate signal C903 are both 0, the output signal B912 is 0 and the output signal A911 is 1; otherwise, the output signal B912 is 1 and the output signal A911 is 0; When the output signal A911 is 0, it means that air is not taken in from here, and the control regulating valve A601 is closed; when the output signal A911 is not 0, it means that air is taken in from here, and the control regulating valve A601 is opened; when the output signal B912 is 0, it means that air is not taken in from here, and the control regulating valve B602 is closed; when the output signal B912 is not 0, it means that air is taken in from here, and the control regulating valve B602 is opened.

[0018] Preferably, in the method, intermediate signals A901, B902, and C903 are signals between 0 and 1, and the analysis and processing unit adjusts the magnitude of output signals A911 and B912 according to the strength of the signals, thereby adjusting the flow rates of the oxidized tail gas and fresh nitrogen entering the oxidation tank 201. The ratio of output signal B912 to output signal A911 is the ratio of the nitrogen flow rate to the oxidized tail gas flow rate.

[0019] Preferably, in the method, the oxidation tail gas utilization device is not provided with a gas holdup online measurement component, and the calculation formulas of the intermediate signal A901, the intermediate signal B902, the output signal B912, and the output signal A911 are as follows: ; Among them, the value range of k1 is 6~20; the value range of k2 is 8~25; the value range of the output signal B912 is [0, 1], and if the calculated value is greater than 1, it is taken as 1.

[0020] Preferably, the value range of k1 is 6-12; the value range of k2 is 8-15.

[0021] Preferably, in the method, the oxidation tail gas utilization device is provided with a gas holdup online measurement component, and the calculation formulas of the intermediate signal A901, the intermediate signal B902, the intermediate signal C903, the output signal B912, and the output signal A911 are as follows: ; Among them, the value range of k1 is 6~20; the value range of k2 is 8~25; the value range of k3 is 20~50; the value range of the output signal B912 is [0, 1], and if the calculated value is greater than 1, it is taken as 1.

[0022] Preferably, the value range of k1 is 6-12; the value range of k2 is 8-15; and the value range of k3 is 20-30.

[0023] When the hydrogen peroxide production system operates stably, the discharge from the oxidation tower contains almost no gas. However, when problems arise in the oxidation process and the discharge contains obvious gas, real-time online measurement of the gas content of the oxidation liquid helps to replenish nitrogen to the oxidation liquid tank in advance to ensure safety.

[0024] The present invention has the following beneficial effects: (1) The present invention changes the original countercurrent oxidation reactor's one-way air inlet into two or three-way air inlet, and the main air inlet is sufficiently far away from the oxidation liquid outlet to reduce the amount of gas carried by the oxidation liquid and reduce the risk of flash explosion in the oxidation liquid tank; the air intake of the main air inlet is reduced to reduce the entrainment of the gas phase, and the hydrogen peroxide concentration near the main air inlet is reduced to reduce the decomposition of hydrogen peroxide caused by a large amount of gas; (2) Part of the gas phase enters the system through microbubbles, which can make the gas-liquid two-phase reaction more complete, further improving the conversion rate of the hydrogenated liquid and the yield of hydrogen peroxide. In addition, since the microbubble flow is relatively gentle, a gas distributor is added below the microbubble generator to use large bubbles to stir the microbubble flow, further improving the mass transfer and heat transfer effects at different positions. (3) The present invention comprises two sets of oxygen content online measurement components and one set of gas holdup online measurement components, and adds an analysis and processing unit. The output signal of the analysis and processing program is adjusted in real time through the measurement signal, thereby reducing the amount of fresh nitrogen as much as possible while ensuring the safety of the oxidation tank, thereby reducing costs and improving economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of a countercurrent oxidation device for producing hydrogen peroxide according to the present invention; Figure 2 Schematic diagram of a countercurrent oxidation apparatus for producing hydrogen peroxide with an online gas holdup measurement assembly according to the present invention; Figure 3 Schematic diagram of a three-way air inlet countercurrent oxidation device for producing hydrogen peroxide according to the present invention; In the figure: 101, countercurrent oxidation tower; 1011, gas distributor A; 1012, microbubble generator; 1013, gas distributor C; 1015, tower plate; 1016, liquid distributor; 1018, gas-liquid separation component; 111, hydrogenation liquid feed pipeline; 112, oxidation liquid discharge pipeline; 121, gas feed pipeline A; 1211, gas feed pipeline B; 1212, gas feed pipeline C; 122, oxidation tail gas discharge pipeline; 124, gas pipeline; 201, oxidation liquid tank; 221, oxidation tail gas feed pipeline; 231, fresh nitrogen feed pipeline; 601, regulating valve A; 602, regulating valve B; 801, oxidation tail gas oxygen content; 802, venting tail gas oxygen content; 803, gas holdup; 911, output signal A; 921, output signal B. DETAILED DESCRIPTION

[0026] The present invention will be further described below through specific embodiments in conjunction with the accompanying drawings. The following embodiments are merely illustrative and are not intended to limit the scope of protection of the present invention.

[0027] Figure 1 In the process, the gas is distributed from the gas feed pipe A121 through the gas distributor A1011 and then enters the countercurrent oxidation tower 101 and flows upward. The hydrogenated liquid is distributed from the hydrogenated liquid feed pipe 111 through the liquid distributor 111 and then enters the countercurrent oxidation tower 101 and flows downward. Macroscopically, the gas and liquid phases are in countercurrent contact and react in the countercurrent oxidation tower 101. The countercurrent oxidation tower 101 is provided with a tray 1015 to redistribute the gas and liquid. The reaction temperature is 40-65°C and the reaction pressure is 0.10-1.0 MPa; then the gas mixed with a small amount of liquid is separated by the gas-liquid separation component 1018, and the gas leaves the countercurrent oxidation tower 101 from the oxidation tail gas discharge pipe 122 and passes through the tail gas treatment process to cool most of the aromatics and then is further treated or discharged through the gas pipe 124. After judgment by the analysis and processing unit, the other part of the treated oxidation tail gas can be passed through the oxidation tail gas feed pipe 221 to enter the top of the oxidation liquid tank 201, and the oxidation liquid tank 201 also has a nitrogen feed pipe 231; the oxidation tail gas feed pipe 221 and the nitrogen feed pipe 231 are respectively provided with a regulating valve A601 and a regulating valve B602; the liquid enters the oxidation liquid tank 201 through the oxidation liquid discharge pipe 112 at the bottom of the countercurrent oxidation tower 101; The signal input end of the oxygen content online measurement component A is connected to the gas pipeline 124, and the signal output end is connected to the analysis and processing unit; the signal input end of the oxygen content online measurement component B is connected to the oxidation liquid tank 201, and the signal output end is connected to the analysis and processing unit; the signal output end of the analysis and processing unit is respectively connected to the regulating valve A601 and the regulating valve B602; The oxygen content 801 of the oxidized tail gas and the oxygen content 802 of the vented tail gas measured in real time by the oxygen content online measurement component A and the oxygen content online measurement component B are transmitted to the analysis and processing unit. The analysis and processing unit processes the oxygen content 801 of the oxidized tail gas and the oxygen content 802 of the vented tail gas and sends signals 911 and 912 to the control valve A and the control valve B to control the opening of the control valve A601 and the control valve B602 respectively.

[0028] Figure 2 In the oxidation tail gas utilization device, a gas holdup online measurement component is provided. The signal input end of the gas holdup online measurement component is connected to the oxidation liquid discharge pipe 112, and the signal output end is connected to the analysis and processing unit. The working method of the signal processing unit is: (1) The oxygen content online measurement component A, the oxygen content online measurement component B, and the optional gas holdup online measurement component measure the oxidation tail gas oxygen content 801, the venting tail gas oxygen content 802, and the gas holdup 803 in real time and transmit them to the analysis and processing unit; (2) The analysis and processing unit processes the oxidation tail gas oxygen content 801, the venting tail gas oxygen content 802, and the gas holdup 803 to obtain an intermediate signal A901, an intermediate signal B902, and an intermediate signal C903; (3) The analysis and processing unit determines the output signals A911 and B912 according to the magnitudes of the intermediate signals A901, B902, and C903 in accordance with a given method; the output signals A911 and B912 control the openings of the regulating valves A601 and B602, respectively.

[0029] Figure 3 In the figure, the number of gas inlets of the countercurrent oxidation tower 101 is 3, which are gas feed pipeline A121, gas feed pipeline B1211 and gas feed pipeline C1212 from top to bottom. The countercurrent oxidation tower 101 is provided with a gas distributor A1011 connected to the gas feed pipeline A121, a microbubble generator 1012 connected to the gas feed pipeline B1211 and a gas distributor C1013 connected to the gas feed pipeline C1212; the gas enters the countercurrent oxidation tower 101 from the gas feed pipeline A121, the gas feed pipeline B1211 and the gas feed pipeline C1212 respectively through the gas distributor A1011, the microbubble generator 1012 and the gas distributor C1013.

[0030] Example 1

[0031] The gas-liquid countercurrent oxidation device designed according to the present invention is as follows: Figure 1As shown, it includes an oxidation tower, an oxidation tail gas treatment process, an oxidation liquid tank 201, an oxygen content online measurement component and an analysis and processing unit; the gas enters the countercurrent oxidation tower 101 from the gas feed pipe A 121 after being distributed by the gas distributor A 1011 and flows upward, and the hydrogenated liquid enters the countercurrent oxidation tower 101 from the hydrogenated liquid feed pipe 111 after being distributed by the liquid distributor 111 and flows downward. Macroscopically, the gas and liquid phases are in countercurrent contact and react in the countercurrent oxidation tower 101. The countercurrent oxidation tower 101 is provided with a tray 1015 to redistribute the gas and liquid; the gas leaves the countercurrent oxidation tower 101 from the oxidation tail gas discharge pipe 122 and passes through the tail gas treatment process to cool most of the aromatics, and the oxidation tail gas is then The gas pipeline 124 is further processed or vented. After judgment by the analysis and processing unit, another portion of the treated partially oxidized tail gas can be fed into the top of the oxidation liquid tank 201 through the oxidation tail gas feed pipe 221. The oxidation liquid tank 201 also has a nitrogen feed pipe 231. The oxidation tail gas feed pipe 221 and the nitrogen feed pipe 231 are respectively provided with a regulating valve A601 and a regulating valve B602. The liquid enters the oxidation liquid tank 201 through the oxidation liquid discharge pipe 112 at the bottom of the countercurrent oxidation tower 101. The signal input end of the oxygen content online measurement component A is connected to the gas pipeline 124, and the signal output end is connected to the analysis and processing unit; the signal input end of the oxygen content online measurement component B is connected to the oxidation liquid tank 201, and the signal output end is connected to the analysis and processing unit; the signal output end of the analysis and processing unit is respectively connected to the regulating valve A601 and the regulating valve B602; The oxidized tail gas oxygen content 801 and the vented tail gas oxygen content 802 measured in real time by the oxygen content online measurement component A and the oxygen content online measurement component B are transmitted to the analysis and processing unit, and then the analysis and processing unit processes the oxidized tail gas oxygen content 801 and the vented tail gas oxygen content 802 signals to obtain intermediate signals A901 and intermediate signals B902. Finally, the analysis and processing unit determines the output signals A911 and output signals B912 according to the given method based on the sizes of the intermediate signals A901 and intermediate signals B902. The output signals A911 and output signals B912 respectively control the opening of the regulating valves A601 and B602.

[0032] When the oxygen content 801 of the oxidized tail gas measured by the oxygen content online measurement component A is ≤8%, the intermediate signal A901 value is adjusted to 0; when the oxygen content 801 of the oxidized tail gas is greater than 8%, the intermediate signal A901 value is adjusted to 1; when the oxygen content 802 of the vented tail gas measured by the oxygen content online measurement component B is ≤5%, the intermediate signal B902 value is adjusted to 0; when the oxygen content 802 of the vented tail gas is greater than 5%, the intermediate signal B902 value is adjusted to 1; When the value of the intermediate signal B902 is 0: the output signal A911 and the output signal B912 are both 0, and there is no need to introduce nitrogen and oxidized tail gas at this time; when the value of the intermediate signal B902 is 1: if the value of the intermediate signal A901 is 0, the output signal B912 is 0 and the output signal A911 is 1; otherwise, the output signal B912 is 1 and the output signal A911 is 0; when the output signal A911 is 0, it means that air is not introduced from here, and the control valve A601 is closed; when the output signal A911 is not 0, it means that air is introduced from here, and the control valve A601 is opened; when the output signal B912 is 0, it means that air is not introduced from here, and the control valve B602 is closed; when the output signal B912 is not 0, it means that air is introduced from here, and the control valve B602 is opened.

[0033] Working fluid flow rate is 930 m 3 / h, air flow rate is 31000 Nm 3 / h, the oxidation reaction temperature is 50℃, the oxidation tower top pressure is 0.2 MPa, when the exhaust oxygen content in the working liquid tank is greater than 5%, in order to ensure safety, the gas flow rate into the working liquid tank is set to 100 Nm 3 / h.

[0034] At this time, the distribution of the gas phase flow rate under different process conditions is shown in Table 1: Table 1. Flow rate of different gas phases in Example 1

[0035] The oxidation device can operate stably.

[0036] Example 2

[0037] Other designs and operating steps are consistent with those of Example 1, except that the oxidation tail gas utilization device is provided with a gas content online measurement component, the signal input end of the gas content online measurement component is connected to the oxidation liquid discharge pipe 112, and the signal output end is connected to the analysis and processing unit; the number of gas inlets of the countercurrent oxidation tower 101 is 2, and the total gas flow rate is 31,000 Nm3 / h, of which the gas flow rate from the gas feed pipe A121 through the gas distributor A1011 into the countercurrent oxidation tower 101 is 29,450 Nm3 / h, and the gas flow rate from the gas feed pipe B1211 through the microbubble generator 1012 into the oxidation tower is 1,550 Nm3 / h, and the gas distributor 1011 and the microbubble generator 1012 are spaced 1 m apart.

[0038] When the oxygen content 801 of the oxidation tail gas measured by the oxygen content online measurement component A is ≤8%, the intermediate signal A901 is adjusted to 0; when the oxygen content 801 of the oxidation tail gas is greater than 8%, the intermediate signal A901 is adjusted to 1; when the oxygen content 802 of the venting tail gas measured by the oxygen content online measurement component B is ≤5%, the intermediate signal B902 is adjusted to 0; when the oxygen content 802 of the venting tail gas is greater than 5%, the intermediate signal B902 is adjusted to 1; when the gas holdup 803 in the oxidation liquid discharge pipe 112 measured by the gas holdup online measurement component is ≤4%, the input intermediate signal C903 is adjusted to 0; when the gas holdup 803 is greater than 4%, the input intermediate signal C903 is adjusted to 1; When the value of the intermediate signal B902 is 0: the output signal A911 and the output signal B912 are both 0, and there is no need to introduce nitrogen and oxidized tail gas at this time; when the value of the intermediate signal B902 is 1: if the intermediate signal A901 and the intermediate signal C903 are both 0, the output signal B912 is 0 and the output signal A911 is 1; otherwise, the output signal B912 is 1 and the output signal A911 is 0; when the output signal A911 is 0, it means that air is not introduced from here, and the control valve A601 is closed; when the output signal A911 is not 0, it means that air is introduced from here, and the control valve A601 is opened; when the output signal B912 is 0, it means that air is not introduced from here, and the control valve B602 is closed; when the output signal B912 is not 0, it means that air is introduced from here, and the control valve B602 is opened.

[0039] At this time, the distribution of gas phase flow under different process conditions is shown in Table 2: Table 2. Flow rate of different gas phases in Example 2

[0040] The oxidation device can operate stably.

[0041] Example 3

[0042] Other designs and operating steps are consistent with those of Example 1, except that intermediate signal A901 and intermediate signal B902 are signals between 0 and 1, and the oxidation tail gas utilization device is not provided with an online gas holdup measurement component. The calculation formulas for intermediate signal A901, intermediate signal B902, output signal B912, and output signal A911 are as follows: ; Among them, the value of k1 is 6; the value of k2 is 15; the value range of the output signal B912 is [0, 1], and if the calculated value is greater than 1, it is taken as 1.

[0043] At this time, the distribution of gas phase flow under different process conditions is shown in Table 3: Table 3. Flow rate of different gas phases in Example 3

[0044] The oxidation device can operate stably.

[0045] Example 4

[0046] Other designs and operating steps are consistent with those of Example 3, except that the oxidation tail gas utilization device is provided with an online gas holdup measurement component, and the calculation formulas for the intermediate signal A901, intermediate signal B902, intermediate signal C903, output signal A911, and output signal B912 are as follows:

[0047] Among them, the value of k1 is 20, the value of k2 is 8, and the value of k3 is 50; the value range of the output signal B912 is [0, 1], and if the calculated value is greater than 1, it is set to 1; The number of gas inlets of the countercurrent oxidation tower 101 is 3, and the total gas flow rate is 31000 Nm 3 / h, of which the flow rate from the gas feed pipe A121 through the gas distributor A1011 into the countercurrent oxidation tower 101 is 26350 Nm 3 / h, the flow rate from the gas feed pipe B1211 through the microbubble generator 1012 into the oxidation tower is 1550 Nm 3 / h, the flow rate from the gas feed pipe A1212 into the oxidation tower through the gas distributor C1013 is 3100 Nm 3 / h; the distance between the gas distributor 1011 and the microbubble generator 1012 is 4 m, and the height distance between the gas distributor C1013 and the microbubble generator 1012 is 50 cm.

[0048] At this time, the distribution of gas phase flow under different process conditions is shown in Table 4: Table 4. Flow rate of different gas phases in Example 4

[0049] The oxidation device can operate stably.

[0050] Example 5

[0051] The other designs and operation steps are the same as those in Example 4, except that the value of k1 is 12, the value of k2 is 25, and the value of k3 is 20; The number of gas inlets of the countercurrent oxidation tower 101 is 3, and the total gas flow rate is 31000 Nm 3 / h, of which the flow rate from the gas feed pipe A121 through the gas distributor A1011 into the countercurrent oxidation tower 101 is 17050Nm 3 / h, the flow rate from the gas feed pipe B1211 through the microbubble generator 1012 into the oxidation tower is 6200 Nm 3 / h, the flow rate from the gas feed pipe A1212 into the oxidation tower through the gas distributor C1013 is 7750 Nm 3 / h; the distance between the gas distributor 1011 and the microbubble generator 1012 is 1 m, and the height distance between the gas distributor C1013 and the microbubble generator 1012 is 5 cm; the air entering the oxidation tower through the microbubble generator 122 is oxygen-enriched air with an oxygen content of 24%.

[0052] At this time, the distribution of the gas phase flow rate under different process conditions is shown in Table 5.

[0053] Table 5. Flow rate of different gas phases in Example 5

[0054] The oxidation device can operate stably.

[0055] Example 6

[0056] The other designs and operation steps are the same as those in Example 4, except that the value of k1 is 8, the value of k2 is 10, and the value of k3 is 30; The number of gas inlets of the countercurrent oxidation tower 101 is 3, and the total gas flow rate is 31000 Nm 3 / h, of which the flow rate from the gas feed pipe A121 through the gas distributor A1011 into the countercurrent oxidation tower 101 is 23250 Nm 3 / h, the flow rate from the gas feed pipe B1211 through the microbubble generator 1012 into the oxidation tower is 3100 Nm 3 / h, the flow rate from the gas feed pipe A1212 into the oxidation tower through the gas distributor C1013 is 4650 Nm 3 / h; the distance between gas distributor 1011 and microbubble generator 1012 is 2 m, and the height distance between gas distributor C1013 and microbubble generator 1012 is 20 cm. The air entering the oxidation tower through microbubble generator 122 is oxygen-enriched air with an oxygen content of 27%.

[0057] At this time, the distribution of gas phase flow under different process conditions is shown in Table 6: Table 6. Flow rate of different gas phases in Example 6

[0058] The oxidation device can operate stably.

Claims

1. A countercurrent oxidation device for producing hydrogen peroxide, the countercurrent oxidation device comprising a countercurrent oxidation tower (101), an oxidation tail gas treatment process, an oxidation liquid tank (201), an oxygen content online measurement component, and an analysis and processing unit; A gas inlet is provided at the bottom of the countercurrent oxidation tower (101); an oxidation tail gas discharge pipe (122) connected to the oxidation tail gas treatment process is provided at the top of the countercurrent oxidation tower (101); and the oxidation tail gas treatment process is provided with a gas pipe (124); the oxidation liquid tank (201) is provided with a nitrogen pipe (231) and an oxidation tail gas feed pipe (221) connected to the gas pipe (124); and a regulating valve A (601) and a regulating valve B (602) are provided on the oxidation tail gas feed pipe (221) and the nitrogen pipe (231), respectively. The oxygen content online measurement component comprises an oxygen content online measurement component A and an oxygen content online measurement component B. The signal input end of the oxygen content online measurement component A is connected to a gas pipeline (124), and the signal output end is connected to an analysis and processing unit; the signal input end of the oxygen content online measurement component B is connected to an oxidation liquid tank (201), and the signal output end is connected to the analysis and processing unit; and the signal output end of the analysis and processing unit is respectively connected to a regulating valve A (601) and a regulating valve B (602).

2. The countercurrent oxidation device according to claim 1, characterized in that The countercurrent oxidation tower (101) is provided with a hydrogenation liquid feed pipe (111) at the top, and an oxidation liquid discharge pipe (112) connected to the oxidation liquid tank (201) at the bottom; the oxidation tail gas utilization device is provided with a gas holdup online measurement component, the signal input end of the gas holdup online measurement component is connected to the oxidation liquid discharge pipe (112), and the signal output end is connected to the analysis and processing unit.

3. The countercurrent oxidation device according to claim 1, characterized in that The number of the gas inlet is one, namely, a gas feed pipe A (121). A gas distributor A (1011) connected to the gas feed pipe A (121) and a liquid distributor (1016) connected to the hydrogenated liquid feed pipe (111) are provided inside the countercurrent oxidation tower (101).

4. The countercurrent oxidation device according to claim 1, characterized in that There are multiple gas inlets; It is further preferred that the number of gas inlets is two, which are, from top to bottom, a gas feed pipe A (121) and a gas feed pipe B (1211), and a gas distributor A (1011) in communication with the gas feed pipe A (121) and a microbubble generator (1012) in communication with the gas feed pipe B (1211) are provided in the countercurrent oxidation tower (101); It is further preferred that the number of gas inlets is three, which are, from top to bottom, a gas feed pipe A (121), a gas feed pipe B (1211), and a gas feed pipe C (1212). The countercurrent oxidation tower (101) is provided with a gas distributor A (1011) connected to the gas feed pipe A (121), a microbubble generator (1012) connected to the gas feed pipe B (1211), and a gas distributor C (1013) connected to the gas feed pipe C (1212).

5. A process for producing hydrogen peroxide using the countercurrent oxidation device according to any one of claims 1 to 4, comprising the following steps: (1) The oxygen content online measurement component A, the oxygen content online measurement component B, and the optional gas holdup online measurement component measure the oxidation tail gas oxygen content (801), the venting tail gas oxygen content (802), and the gas holdup (803) in real time and transmit them to the analysis and processing unit; (2) The analysis and processing unit processes the oxidation tail gas oxygen content (801), the venting tail gas oxygen content (802), and the gas holdup (803) to obtain an intermediate signal A (901), an intermediate signal B (902), and an intermediate signal C (903); (3) The analysis and processing unit determines the output signal A (911) and the output signal B (912) according to the magnitude of the intermediate signal A (901), the intermediate signal B (902), and the intermediate signal C (903) in accordance with a given method; the output signal A (911) and the output signal B (912) respectively control the opening of the regulating valve A (601) and the regulating valve B (602).

6. The hydrogen peroxide production process according to claim 5, characterized in that: When the countercurrent oxidation device is not provided with a gas holdup online measurement component: when the oxygen content (801) of the oxidation tail gas measured by the oxygen content online measurement component A is ≤8%, the intermediate signal A (901) value is adjusted to 0; when the oxygen content (801) of the oxidation tail gas is >8%, the intermediate signal A (901) value is adjusted to 1; when the oxygen content (802) of the venting tail gas measured by the oxygen content online measurement component B is ≤5%, the intermediate signal B (902) value is adjusted to 0; when the oxygen content (802) of the venting tail gas is >5%, the intermediate signal B (902) value is adjusted to 1; When the value of the intermediate signal B (902) is 0: the output signal A (911) and the output signal B (912) are both 0; When the value of the intermediate signal B (902) is 1: if the intermediate signal A (901) is 0, the output signal B (912) is 0 and the output signal A (911) is 1; otherwise, the output signal B (912) is 1 and the output signal A (911) is 0; When the output signal A (911) is 0, it means that air is not taken in from here, and the control regulating valve A (601) is closed; when the output signal A (911) is not 0, it means that air is taken in from here, and the control regulating valve A (601) is opened; when the output signal B (912) is 0, it means that air is not taken in from here, and the control regulating valve B (602) is closed; when the output signal B (912) is not 0, it means that air is taken in from here, and the control regulating valve B (602) is opened.

7. The hydrogen peroxide production process according to claim 5, characterized in that: When the countercurrent oxidation device is provided with a gas content online measurement component: when the oxygen content (801) of the oxidation tail gas measured by the oxygen content online measurement component A is ≤8%, the intermediate signal A (901) is adjusted to 0, and when the oxygen content (801) of the oxidation tail gas is >8%, the intermediate signal A (901) is adjusted to 1; when the oxygen content (802) of the venting tail gas measured by the oxygen content online measurement component B is ≤5%, the intermediate signal B (902) is adjusted to 0, and when the oxygen content (802) of the venting tail gas is >5%, the intermediate signal B (902) is adjusted to 1; when the gas content (803) in the oxidation liquid discharge pipe (112) measured by the gas content online measurement component is ≤4%, the input intermediate signal C (903) is adjusted to 0, and when the gas content (803) is >4%, the input intermediate signal C (903) is adjusted to 1; When the value of the intermediate signal B (902) is 0: the output signal A (911) and the output signal B (912) are both 0; When the value of the intermediate signal B (902) is 1: if the intermediate signal A (901) and the intermediate signal C (903) are both 0, the output signal B (912) is 0 and the output signal A (911) is 1; otherwise, the output signal B (912) is 1 and the output signal A (911) is 0; When the output signal A (911) is 0, it means that air is not taken in from here, and the control regulating valve A (601) is closed; when the output signal A (911) is not 0, it means that air is taken in from here, and the control regulating valve A (601) is opened; when the output signal B (912) is 0, it means that air is not taken in from here, and the control regulating valve B (602) is closed; when the output signal B (912) is not 0, it means that air is taken in from here, and the control regulating valve B (602) is opened.

8. The hydrogen peroxide production process according to claim 5, characterized in that: In the method, intermediate signal A (901), intermediate signal B (902), and intermediate signal C (903) are signals between 0 and 1, and the analysis and processing unit adjusts the magnitude of output signal A (911) and output signal B (912) according to the strength of the signals, thereby adjusting the flow rate of oxidation tail gas and fresh nitrogen entering the oxidation liquid tank (201).

9. The hydrogen peroxide production process according to claim 5, characterized in that: The oxidation tail gas utilization device is not provided with a gas holdup online measurement component, and the calculation formulas of the intermediate signal A (901), the intermediate signal B (902), the output signal B (912), and the output signal A (911) are as follows: ； The value range of k1 is 6 to 20; the value range of k2 is 8 to 25; the value range of the output signal B (912) is [0, 1], and if the calculated value is greater than 1, it is set to 1; Preferably, the value range of k1 is 6-12; the value range of k2 is 8-15.

10. The hydrogen peroxide production process according to claim 5, characterized in that: The oxidation tail gas utilization device is provided with a gas holdup online measurement component, and the calculation formulas of the intermediate signal A (901), the intermediate signal B (902), the intermediate signal C (903), the output signal B (912), and the output signal A (911) are as follows: ； The value range of k1 is 6~20; the value range of k2 is 8~25; the value range of k3 is 20~50; the value range of the output signal B (912) is [0, 1], and if the calculated value is greater than 1, it is set to 1; Preferably, the value range of k1 is 6-12; the value range of k2 is 8-15; and the value range of k3 is 20-30.

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