Oxidation device for producing cumene hydroperoxide with multi-stage dispersion structure

Abstract

The utility model belongs to hydrogen peroxide cumene production technical field, concretely relates to a kind of hydrogen peroxide cumene production with oxidation device of multistage dispersion structure. The hydrogen peroxide cumene production with oxidation device of multistage dispersion structure, including cumene storage tank, cumene storage tank is connected with preheater by feed pump, and preheater is connected with cumene feed inlet in upper portion of oxidation tower;Oxidation tower top is connected with tail gas condenser by gas phase pipeline, and tail gas condenser bottom is connected with gas-liquid separation tank. The hydrogen peroxide cumene production with oxidation device of multistage dispersion structure of the utility model is matched by air section feeding and internal structure, increases mass transfer area, improves oxidation reaction rate and selectivity;Recovery reaction heat preheats raw material, stabilizes temperature field, reduces energy consumption;Tower top separates tail gas droplet, recovers cumene, guarantees process stability, improves device safety.

Description

Technical Field

[0001] This utility model belongs to the field of cumene hydrogen peroxide production technology, specifically relating to an oxidation device for cumene hydrogen peroxide production with a multi-level dispersion structure. Background Technology

[0002] Cumene hydroperoxide (CHP) is the core raw material for the production of dicumyl peroxide (DCP). As a commonly used organic peroxide, DCP is mainly used in rubber crosslinking agents, plastic polymerization initiators, and other fields. The core step in its production is that cumene reacts with oxygen in an oxidation tower to produce cumene hydroperoxide, which is then further condensed to obtain DCP. However, in actual production, the oxygen introduced from the bottom of the tower is difficult to disperse evenly throughout the tower, which can easily lead to local oxygen concentrations that are too high or too low, affecting the overall oxidation efficiency. When liquid cumene enters from the top of the oxidation tower, it cannot be evenly dispersed across the cross-section of the tower, causing cumene to concentrate in the central area of ​​the tower and flow down, while there is less material near the tower wall, resulting in an uneven reaction.

[0003] CN213557027U discloses an oxidation tower device for producing cumene hydroperoxide. The tower body includes a rotatable guide tube with uniformly distributed blades welded vertically to its inner wall. The upper and lower ends of the tube are slidably connected to upper and lower support rings of the tower body. The guide tube has a double-layered hollow structure with small holes in its inner wall. A ring-shaped opening at the top connects to a through-hole in the upper support ring, which is connected to a gas supply pipe extending out of the tower body. A fixed gear is fitted on the outer wall of the guide tube, meshing with a drive gear driven by a motor. The top of the tower body has a feed pipe with an atomizing nozzle and an exhaust pipe, while the bottom has an inlet pipe, a discharge port with a valve, and support legs. This device uses the rotation of the guide tube to drive the blades to form a wind wall, which, combined with the gas supply pipe, promotes gas-liquid contact and improves oxidation efficiency. However, its rotatable guide tube design has poor practical applicability, and it only changes the feed of liquid cumene, thus having a limited effect on promoting gas-liquid contact. Utility Model Content

[0004] The purpose of this invention is to provide an oxidation device for the production of cumene hydroperoxide with a multi-stage dispersion structure, so as to solve the problems of low oxidation efficiency and poor oxidation effect in the production process of cumene hydroperoxide.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] An oxidation device for producing cumene hydroperoxide with a multi-stage dispersion structure includes an oxidation tower, a cumene storage tank, a tail gas condenser, and a gas-liquid separator. The cumene storage tank is connected to a preheater via a feed pump, and the preheater is equipped with a pipeline connected to the upper part of the oxidation tower. The top of the oxidation tower is connected to the tail gas condenser via a gas phase pipeline, the bottom of the tail gas condenser is connected to the gas-liquid separator, and the top of the gas-liquid separator is connected to the tail gas pipeline. A drain pipeline is provided at the bottom of the oxidation tower, and a discharge port is provided on the bottom sidewall and connected to the discharge pipeline. The oxidation tower can be divided into a top separation section, a reaction section, and a bottom storage section from top to bottom. A demister is provided in the top separation section, and a conical guide tube is connected to the lower part of the demister. A gas inlet is provided at the bottom of the reaction section and connected to an air pipeline. A pipeline is provided in the bottom storage section to return to the middle of the reaction section, and a circulating cooler, a circulating pump, and a mixer are sequentially installed on the pipeline.

[0007] Preferably, a flow guiding component is provided inside the conical flow guide cylinder. The flow guiding component consists of an axial support column and a flow guiding blade spiraling around it. The conical flow guide cylinder, together with the flow guiding blade, separates the isopropylbenzene droplets carried in the oxidation tail gas, preventing the droplets from entering subsequent equipment and avoiding equipment corrosion and a decrease in heat exchange efficiency.

[0008] Preferably, the reaction section is provided with an isopropylbenzene inlet, a circulating liquid inlet, and a gas inlet from top to bottom. Both the isopropylbenzene inlet and the circulating liquid inlet are internally connected to annular feed pipes. A trough-type liquid distributor is provided at the lower part of the annular feed pipe, and a baffle plate is provided at the lower part of the trough-type liquid distributor. Several evenly distributed vent holes are provided on the baffle plate. The trough-type liquid distributor and the baffle plate are arranged crosswise in the tower. The gas inlet is internally connected to annular gas distribution disk, and nozzles are provided on the annular gas distribution disk. After the gas enters the annular cavity through the main pipe, it is distributed to each nozzle along the radial branch pipes to disperse the air in the air pipeline into the interior of the oxidation tower. Further, the isopropylbenzene inlet is located at the upper end of the reaction section, the circulating liquid inlet is located in the middle of the reaction section, and the gas inlet is at the lower end of the reaction section.

[0009] Preferably, the liquid storage section at the bottom of the tower is equipped with a side stirrer.

[0010] Preferably, the air pipeline is provided with a branch connected to the feed end of the mixer, and a three-way gas valve is installed at the branch point to allow air to enter from the lower gas inlet and the middle circulating liquid inlet of the oxidation tower reaction section respectively. Furthermore, each pipeline is provided with a regulating valve to control the gas flow rate.

[0011] Preferably, a pressure detection device is installed at the top of the oxidation tower, and a back pressure valve is installed on the top gas phase pipeline to control the pressure in the reaction and ensure that the reaction proceeds stably.

[0012] Preferably, the shell-side inlet of the tail gas condenser is connected to the cooling water inlet pipe, and the shell-side outlet is connected to the shell-side of the circulating cooler through the cooling water circulation pipe. This is used to transfer the heat generated by the exothermic oxidation of cumene. The shell-side of the circulating cooler is equipped with a pipe connected to the shell-side of the preheater, so that the heat transferred by the reaction is used to preheat the raw material cumene, reducing the impact of temperature difference on the reaction. The circulating water after heat exchange is returned to the plant's circulating water system. Furthermore, the shell-side of the preheater is connected to a steam tracing pipe for preheating cumene in the initial stage of the reaction when there is no residual heat to utilize. The condensate generated after steam heat exchange is transported to the subsequent equipment through the pipe.

[0013] Preferably, the bottom of the gas-liquid separator is provided with a pipeline for returning to the feed end of the preheater to achieve the reuse of cumene.

[0014] Preferably, the trough-type liquid distributor consists of a top main distribution trough, a lower sub-distribution trough, and distribution holes. The distribution holes are located on the connection surface between the main distribution trough and the sub-distribution trough, as well as on the side wall of the sub-distribution trough. The main trough receives the liquid and distributes it evenly to the sub-distribution trough through the distribution holes. The sub-distribution trough evenly sprays the liquid into the tower through the distribution holes on its side wall, thereby achieving uniform liquid distribution across the tower cross section.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0016] (1) The oxidation device for producing cumene hydroperoxide with a multi-stage dispersion structure of this utility model forms a multi-stage gas-liquid mass transfer interface by segmented air feeding and in-tower tank liquid distributor and baffle plate, which increases the gas-liquid contact area and improves the oxidation reaction rate and CHP selectivity.

[0017] (2) The heat generated by the reaction is used to preheat cumene, stabilize the reaction temperature field, reduce temperature fluctuations, and recover the reaction heat to reduce energy consumption, thus ensuring the stability and safety of the reaction.

[0018] (3) A conical cylinder and a flow guiding component are installed at the top of the oxidation tower to separate the tail gas droplets and prevent equipment corrosion. The gas-liquid separator recovers cumene for reuse, ensuring process stability and reducing raw material loss. At the same time, it avoids the direct discharge of high-concentration cumene vapor into the atmosphere, thus improving the safety of the unit. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the oxidation device for producing cumene hydroperoxide with a multi-stage dispersion structure according to this utility model.

[0020] Figure 2 This is a schematic diagram of the oxidation tower in this utility model;

[0021] Figure 3 This is a schematic diagram of the structure of the tank-type liquid distributor of this utility model.

[0022] In the diagram: 1. Oxidation tower; 101. Demister; 102. Conical guide tube; 103. Support column; 104. Guide vane; 105. Annular feed pipe; 106. Tank-type liquid distributor; 1061. Main distribution tank; 1062. Sub-distribution tank; 1063. Liquid distribution hole; 107. Baffle plate; 108. Annular gas distribution plate; 2. Cumene storage tank; 3. Tail gas condenser; 4. Gas-liquid separator; 5. Circulating cooler; 6. Circulating pump; 7. Mixer; 8. Preheater; 9. Feed pump; 10. Air pipeline; 11. Cooling water inlet pipeline; 12. Cooling water circulation pipeline; 13. Tail gas pipeline; 14. Discharge pipeline; 15. Sewage discharge pipeline; 16. Side agitator; 17. Gas three-way valve; 18. Back pressure valve; 19. Pressure detection device. Detailed Implementation

[0023] The specific technical solution of this utility model will be further described below with reference to the accompanying drawings.

[0024] like Figures 1-3 As shown, the oxidation device for producing cumene hydroperoxide with a multi-stage dispersion structure includes an oxidation tower 1 and a cumene storage tank 2. The cumene storage tank 2 is connected to a preheater 8 via a feed pump 9. The preheater 8 is equipped with a pipeline connected to the upper part of the oxidation tower 1. The top of the oxidation tower 1 is connected to a tail gas condenser 3 via a gas phase pipeline. The bottom of the tail gas condenser 3 is connected to a gas-liquid separator 4. The top of the gas-liquid separator 4 is connected to a tail gas pipeline 13, and the bottom is equipped with a return flow to the feed end of the preheater 8. Piping; Oxidation tower 1 can be divided into a top separation section, a reaction section and a bottom storage section from top to bottom. The top separation section is equipped with a demister 101, and the lower part of the demister 101 is connected to a conical guide tube 102. The reaction section is equipped with an isopropylbenzene inlet, a circulating liquid inlet and a gas inlet from top to bottom. The bottom storage section is equipped with a pipeline that returns to the circulating liquid inlet in the middle of the reaction section. A circulating cooler 5, a circulating pump 6 and a mixer 7 are installed on the pipeline in sequence. The bottom storage section is equipped with a side agitator 16.

[0025] The conical guide tube 102 is equipped with a flow guiding assembly, which consists of an axial support column 103 and a flow guiding blade 104 spiraling around it.

[0026] Both the cumene inlet and the circulating liquid inlet are internally connected to annular feed pipes 105. A trough-type liquid distributor 106 is installed at the lower part of the annular feed pipe 105, and a baffle plate 107 is installed at the lower part of the trough-type liquid distributor 106. Several evenly distributed vent holes are provided on the baffle plate 107. The trough-type liquid distributor 106 and the baffle plate 107 are arranged crosswise in the tower. An annular gas distribution disk 108 is internally connected to the gas inlet, and a nozzle is provided on the annular gas distribution disk 108. The trough-type liquid distributor 106 consists of a top main distribution trough 1061, a lower sub-distribution trough 1062, and liquid distribution holes 1063. The liquid distribution holes 1063 are located on the connection surface between the main distribution trough 1061 and the sub-distribution trough 1062, as well as on the side wall of the sub-distribution trough 1062.

[0027] The gas inlet at the bottom of the reaction section is connected to the air pipeline 10. The air pipeline 10 is provided with a branch that connects to the feed end of the mixer 7. A gas three-way valve 17 is installed at the branch point, and a regulating valve is installed on each pipeline.

[0028] The bottom of the oxidation tower 1 is equipped with a sewage discharge pipe 15, and the bottom side wall is equipped with a discharge port connected to the discharge pipe 14; the top of the oxidation tower 1 is equipped with a pressure detection device 19, and the top gas phase pipe is equipped with a back pressure valve 18.

[0029] The shell-side inlet of the exhaust gas condenser 3 is connected to the cooling water inlet pipe 11, and the shell-side outlet is connected to the shell-side of the circulating cooler 5 through the cooling water circulation pipe 12. The shell-side of the circulating cooler 5 is provided with a pipe connected to the shell-side of the preheater 8, and the shell-side of the preheater 8 is also connected to a steam tracing pipe.

[0030] The mixer is used to thoroughly mix the circulating liquid with the branch air to form a uniform gas-liquid mixture before sending it into the reaction section of the oxidation tower. Its specific structure is a conventional type available on the market, so it will not be described in detail.

[0031] The above-mentioned oxidation unit for the production of cumene hydroperoxide with a multi-stage dispersion structure operates as follows:

[0032] First, the cumene in the cumene storage tank 2 is sent to the preheater 8 via the feed pump 9. After being preheated to 60-80℃, it enters the cumene inlet at the top of the oxidation tower 1 through the pipeline. It then flows into the trough-type liquid distributor 106 through the annular feed pipe 105. The trough-type liquid distributor 106 can evenly distribute the liquid into the tower, achieving uniform liquid distribution across the tower cross section. Air is transported through the air pipeline 10. Part of it enters the oxidation tower 1 through the gas inlet at the bottom of the reaction section and is dispersed into the oxidation tower 1 through the annular gas distribution plate 108. The other part enters the mixer 7 on the reflux pipeline of the bottom liquid storage section of the tower through a branch of the air pipeline 10. After being mixed with the circulating liquid, the gas enters the tower through the circulating liquid inlet in the middle of the reaction section. The regulating valves on each pipeline can precisely control the gas flow rate. In the initial stage of the reaction, only air is fed into the mixer 7. After the reaction stabilizes, the circulating liquid is turned on to circulate. The heat generated by the oxidation of cumene is transferred by the circulating cooler 5 to prevent the temperature in the oxidation tower 1 from becoming too high and causing danger. Through circulation, the occurrence of side reactions is reduced, ensuring oxidation efficiency and selectivity. In the initial stage of the reaction, the heat medium of the preheater 8 is steam. After the reaction stabilizes, the circulating water in the shell side of the circulating cooler 5 is used as the heat medium. At this time, the cumene is preheated to 60°C.

[0033] Inside the oxidation tower 1, cumene, circulating liquid, and air come into full contact and undergo an oxidation reaction to generate cumene hydrogen peroxide. During this process, the trough-type liquid distributor 106 and the baffle plate 107 play important roles. The trough-type liquid distributor 106 distributes the liquid evenly, and the evenly distributed air holes on the baffle plate 107 cause the gas and liquid to change their flow direction and collide with each other multiple times during the rising and falling process, which further increases the gas-liquid contact area and contact time, forming a multi-stage gas-liquid mass transfer interface, thereby improving the oxidation reaction rate and CHP selectivity. At the same time, the side stirring 16 in the bottom liquid storage section of the tower also enhances the mixing of materials and ensures that the reaction proceeds fully.

[0034] During the reaction, the tail gas rises to the top of the tower. The conical guide tube 102 set in the separation section at the top of the tower, together with the guide assembly consisting of an axial support column 103 and a spiral guide blade 104, further separates the isopropylbenzene droplets carried in the oxidizing tail gas. The demister 101 can further remove the droplets in the tail gas, prevent the droplets from entering the downstream equipment, and avoid equipment corrosion and heat exchange efficiency reduction.

[0035] The pre-treated tail gas enters the tail gas condenser 3. The cooled gas-liquid mixture enters the gas-liquid separator 4. The separated liquid (cumene) returns to the feed end of the preheater 8 via the reflux pipeline, realizing the reuse of cumene. The separated gas is transported to the subsequent processing device via the tail gas pipeline 13. In addition, the pressure detection device 19 and back pressure valve 18 at the top of the oxidation tower 1 monitor and control the pressure in the reaction in real time to ensure the stable progress of the reaction. Cooling water is introduced into the shell side of the tail gas condenser 3 through the cooling water inlet pipeline 11 to absorb the heat in the tail gas. The cooling water enters the shell side of the circulating cooler 5 via the cooling water circulation pipeline 12 to transfer the heat released by the oxidation reaction. It then flows to the shell side of the preheater 8 to use the heat transferred by the reaction to preheat the raw material cumene, reducing the impact of temperature difference on the reaction. The circulating water after heat exchange is returned to the factory circulating water system. The heat exchange device adopts countercurrent heat exchange, and the temperature is monitored throughout the reaction process.

[0036] The reacted material is temporarily stored in the bottom storage section of the tower, and the qualified product is discharged through the discharge port on the bottom side wall via the discharge pipe 14. After long-term operation, the viscosity of the reacted material increases and impurities are easily deposited at the bottom, so they are periodically discharged through the bottom drain pipe 15.

Claims

1. An oxidation device for producing cumene hydroperoxide with a multi-level dispersion structure, characterized in that, It includes an oxidation tower (1) and an isopropylbenzene storage tank (2). The isopropylbenzene storage tank (2) is connected to a preheater (8) via a feed pump (9). The preheater (8) is provided with a pipeline connected to the upper part of the oxidation tower (1). The top of the oxidation tower (1) is connected to a tail gas condenser (3) via a gas phase pipeline. The bottom of the tail gas condenser (3) is connected to a gas-liquid separator (4). The oxidation tower (1) can be divided into a top separation section, a reaction section and a bottom storage section from top to bottom. The top separation section is equipped with a demister (101), and the lower part of the demister (101) is connected to a conical guide tube (102). The reaction section is equipped with an isopropylbenzene inlet, a circulating liquid inlet and a gas inlet from top to bottom. The bottom storage section is equipped with a pipeline that returns to the circulating liquid inlet in the middle of the reaction section. The bottom storage section is equipped with a side agitator (16).

2. The oxidation apparatus for producing cumene hydroperoxide with a multi-level dispersion structure according to claim 1, characterized in that, The conical guide tube (102) is equipped with a flow guiding assembly, which consists of an axial support column (103) and a flow guiding blade (104) spiraling around it.

3. The oxidation apparatus for producing cumene hydroperoxide with a multi-level dispersion structure according to claim 1, characterized in that, Both the cumene inlet and the circulating liquid inlet are internally connected to an annular feed pipe (105). A trough-type liquid distributor (106) is installed at the lower part of the annular feed pipe (105). A baffle plate (107) is installed at the lower part of the trough-type liquid distributor (106). Several evenly distributed vent holes are provided on the baffle plate (107). The trough-type liquid distributor (106) and the baffle plate (107) are arranged crosswise in the tower. An annular gas distribution plate (108) is internally connected to the gas inlet. A nozzle is provided on the annular gas distribution plate (108).

4. The oxidation apparatus for producing cumene hydroperoxide with a multi-level dispersion structure according to claim 3, characterized in that, The trough-type liquid distributor (106) consists of a top main distribution trough (1061), a lower sub-distribution trough (1062), and a liquid distribution hole (1063). The liquid distribution hole (1063) is located on the connecting surface between the main distribution trough (1061) and the sub-distribution trough (1062) and on the side wall of the sub-distribution trough (1062).

5. The oxidation apparatus for producing cumene hydroperoxide with a multi-level dispersion structure according to claim 1, characterized in that, The gas inlet at the bottom of the reaction section is connected to the air pipeline (10). The air pipeline (10) is provided with a branch that is connected to the feed end of the mixer (7). A gas three-way valve (17) is installed at the branch point. A regulating valve is installed on each pipeline.

6. The oxidation apparatus for producing cumene hydroperoxide with a multi-level dispersion structure according to claim 1, characterized in that, The bottom of the oxidation tower (1) is equipped with a sewage discharge pipe (15), and the bottom side wall is equipped with a discharge port connected to the discharge pipe (14).

7. The oxidation apparatus for producing cumene hydroperoxide with a multi-level dispersion structure according to claim 1, characterized in that, A pressure detection device (19) is installed at the top of the oxidation tower (1), and a back pressure valve (18) is installed on the top gas phase pipeline.

8. The oxidation apparatus for producing cumene hydroperoxide with a multi-level dispersion structure according to claim 1, characterized in that, A circulating cooler (5), a circulating pump (6), and a mixer (7) are sequentially installed on the pipeline that returns to the circulating liquid inlet in the middle of the reaction section.

9. The oxidation apparatus for producing cumene hydroperoxide with a multi-level dispersion structure according to claim 8, characterized in that, The shell-side inlet of the exhaust gas condenser (3) is connected to the cooling water inlet pipe (11), and the shell-side outlet is connected to the shell-side of the circulating cooler (5) through the cooling water circulation pipe (12). The shell-side of the circulating cooler (5) is provided with a pipe connected to the shell-side of the preheater (8), and the shell-side of the preheater (8) is also connected to a steam tracing pipe.

10. The oxidation apparatus for producing cumene hydroperoxide with a multi-level dispersion structure according to claim 1, characterized in that, The top of the gas-liquid separator (4) is connected to the tail gas pipeline (13), and the bottom is provided with a pipeline that returns to the feed end of the preheater (8).

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