Fiber membrane regeneration tower for producing hydrogen peroxide by anthraquinone method

Abstract

The fibrous membrane regeneration tower comprises a tower body and a tower kettle, the tower body is vertical, the tower kettle is horizontal, the bottom of the tower body is open, the tower body stands on the tower kettle, and the tower wall of the tower body extends into the tower kettle; the tower body sequentially comprises a tower body upper section, a tower body middle section and a tower body lower section from top to bottom, the tower body upper section is filled with oleophylic fibers, the tower body middle section is filled with hydrophilic fibers, and the tower body lower section is filled with hydrophobic fibers; a working liquid inlet and a hydrogenated liquid inlet are formed in the upper part of the tower body upper section; an alkali liquid inlet is formed in the top of the tower body middle section; the bottom of the tower kettle is provided with an alkali liquor outlet, and the top is provided with an oil phase outlet. According to the fiber membrane regeneration tower, the upper section is filled with oleophylic fibers, the middle section of the tower body is filled with hydrophilic fibers, and the lower section of the tower body is filled with hydrophobic fibers, so that the effects of stable liquid membrane, efficient mixing, good regeneration effect, rapid separation and the like are achieved.

Description

Technical Field

[0001] The present invention relates to the field of hydrogen peroxide production by the anthraquinone method, and particularly to a fiber membrane regeneration tower for hydrogen peroxide production by the anthraquinone method. Background Art

[0002] Hydrogen peroxide is a green oxidant and has wide applications in the chemical industry. Currently, hydrogen peroxide is generally produced by the anthraquinone method in industry. In the anthraquinone method process, a working solution is composed of a carrier and a solvent in a certain proportion. Generally, 2-ethylanthraquinone, 2-butylanthraquinone, 2-pentylanthraquinone or a mixture thereof is used as the carrier, and a mixture of heavy aromatic hydrocarbons, trioctyl phosphate, o-methylcyclohexyl acetate, diisobutyl methanol, tetrabutylurea, etc. is used as the solvent. The working solution circulates in the system in the order of hydrogenation, oxidation, extraction, and post-treatment, and hydrogen peroxide is produced. In the hydrogenation process, the working solution undergoes a hydrogenation reaction under the action of a catalyst to obtain a hydrogenated solution; in the oxidation process, the hydrogenated solution reacts with oxygen to obtain an oxidized solution; in the extraction process, hydrogen peroxide in the oxidized solution is extracted by water to obtain an aqueous hydrogen peroxide solution (extraction solution). The working solution flowing out of the extraction process undergoes dehydration, removal of hydrogen peroxide, and regeneration of degradation products in the post-treatment process, and then enters the circulating working solution storage tank to complete one cycle.

[0003] During the continuous hydrogenation and oxidation reactions of the working solution, the solvent and alkyl anthraquinone will degrade, producing substances such as carboxylic acids, phenols, aldehydes, etc. (JP6428622B2), which change the physical properties of the working solution and may seriously affect the normal operation of the extraction tower in severe cases. Treating the working solution with an alkali solution (generally an aqueous solution of potassium carbonate or sodium hydroxide) can remove or regenerate the degradation products in the working solution and reduce the content of degradation products. For example, when the working solution passes through a drying tower filled with an aqueous solution of potassium carbonate or an alkali washing tower filled with an aqueous solution of sodium hydroxide, some of the degradation products are regenerated into effective anthraquinone, and some of the degradation products are dissolved in the alkali solution and carried out of the system with the alkali solution.

[0004] The use of fiber membrane technology can strengthen the mass transfer between the alkali solution and the working solution (CN114180773A). In the fiber membrane regeneration tower, the working solution and the alkali solution form a liquid film-like non-dispersed mass transfer state, which has the characteristics of less liquid holdup and good regeneration effect. However, in the front part of the fiber membrane regeneration tower, the impact and turbulence of the working solution are strong, resulting in the alkali solution not being able to stably adhere to the surface of the fiber filaments to form a liquid film. There is a poor contact area between the oil and water phases in the front part of the fiber membrane regeneration tower, leading to waste of the fiber filaments in this part.

[0005] Under alkaline conditions, epoxy anthraquinone in anthraquinone degradation products can be regenerated into effective anthraquinone when alkyl anthrahydroquinone is involved. Therefore, after the working solution and the hydrogenated solution are mixed and then jointly treated with alkaline substances such as alkaline solution and activated alumina for regeneration, the regeneration effect of the degradation products can be improved. In the working solution and the hydrogenated solution, the molecular weight of alkyl anthraquinone is relatively large, and simple mechanical mixing cannot ensure the uniform mixing of the hydrogenated solution and the working solution. Appropriate means are needed to achieve the uniform mixing of the liquid-liquid two phases in order to promote the regeneration effect. Generally, external equipment (such as pipeline mixers, stirring kettles, etc.) is required to achieve the uniform mixing of the working solution, the hydrogenated solution, and the alkaline solution. Adding equipment makes the control complex and cannot guarantee the mixing effect. Summary of the Invention

[0006] To solve the above problems, the present invention proposes a fiber membrane regeneration tower for producing hydrogen peroxide by the anthraquinone method. The fiber membrane regeneration tower guides the working solution and the hydrogenated solution to the middle section of the tower body through lipophilic fiber filaments, reducing the impact on the alkaline solution film on the surface of the hydrophilic fiber filaments; the bent and intertwined lipophilic fiber filaments achieve the uniform mixing of the working solution and the hydrogenated solution without additional equipment; the hydrophobic fiber filaments are arranged to accelerate the oil-water separation; the tower body structure design prevents gas backflow, and the tower bottom baffle ensures the oil-water stratification; it has the advantages of stable liquid film, high mixing efficiency, good regeneration effect, and rapid separation.

[0007] The technical solution of the present invention is as follows: A fiber membrane regeneration tower for producing hydrogen peroxide by the anthraquinone method, which comprises two parts: a tower body 101 and a tower bottom 102. The tower body 101 is vertical, the tower bottom 102 is horizontal, the bottom of the tower body 101 is open, the tower body 101 stands on the tower bottom 102, and the tower wall of the tower body 101 extends into the interior of the tower bottom 102; The tower body 101 is successively divided into an upper tower body section 1011, a middle tower body section 1012, and a lower tower body section 1013 from top to bottom. The upper tower body section 1011 is filled with lipophilic fiber filaments, the middle tower body section 1012 is filled with hydrophilic fiber filaments, and the lower tower body section 1013 is filled with hydrophobic fiber filaments; The upper part of the upper tower body section 1011 is provided with a working solution inlet 01 and a hydrogenated solution inlet 02, and the top of the middle tower body section 1012 is provided with an alkaline solution inlet 03; The bottom of the tower bottom 102 is provided with an alkaline solution outlet 05, and the top is provided with an oil phase outlet 04.

[0008] After the hydrogenated liquid and the working liquid enter the fiber membrane regeneration tower from the upper part of the upper section of the tower body, they flow downward. Under the action of the lipophilic fiber filaments in the upper section of the tower body, they are fully mixed to form a mixed working liquid, which enters the middle section of the tower body. The lye enters the fiber membrane regeneration tower from the top of the middle section of the tower body and adheres to the surface of the hydrophilic fiber filaments and flows downward. The mixed working liquid and the lye are fully contacted and reacted under the action of the hydrophilic fiber filaments in the middle section of the tower body, and the degradation products in the mixed working liquid are regenerated. The mixed working liquid and the lye flow into the lower section of the tower body of the fiber membrane regeneration tower together. After the mixed working liquid and the lye pass through the guiding action of the hydrophobic fiber filaments in the lower section of the tower body, they enter the tower kettle of the fiber membrane regeneration tower, and the mixed working liquid and the lye are quickly separated in the tower kettle. The mixed working liquid flows out from the top of the tower kettle, and the lye flows out from the bottom of the tower kettle.

[0009] The liquid level of the tower body of the fiber membrane regeneration tower is controlled by controlling the outflow flow rate of the mixed working liquid at the top of the tower kettle.

[0010] The length of the upper section 1011 of the tower body is 10% - 30% of the total length of the tower body, preferably 15%, 20%, 25%; the length of the middle section 1012 of the tower body is 60% - 85% of the total length of the tower body, preferably 65%, 75%, 80%; the length of the lower section 1013 of the tower body is 5% - 10% of the total length of the tower body, preferably 7 - 9%.

[0011] The lipophilic fiber filaments, hydrophilic fiber filaments, and hydrophobic fiber filaments are all curved.

[0012] The lipophilic fiber filaments are irregularly and evenly intertwined in the upper section of the tower body, and the ratio of the bending diameter of the lipophilic fiber filaments to the radius of the tower body is 1 - 2.

[0013] The material of the lipophilic fiber filaments is one of polyvinylidene fluoride, polystyrene, and silane coupling agent - modified stainless steel; the material of the hydrophilic fiber filaments is one of electrochemically oxidized stainless steel, acrylic - grafted modified stainless steel, and polyvinyl alcohol - modified stainless steel; the material of the hydrophobic fiber filaments is one of polytetrafluoroethylene, silicone - chemical vapor deposition - modified stainless steel, and electrochemically etched stainless steel.

[0014] The volume flow rate ratio of the working liquid to the hydrogenated liquid is 10 - 1.

[0015] The volume flow rate ratio of the mixed working liquid to the lye is 2000 - 20.

[0016] The lye is an aqueous solution of one or more substances among sodium hydroxide, potassium carbonate, potassium hydroxide, and sodium carbonate.

[0017] The distance between the bottom of the tower body and the bottom of the tower kettle is 1 / 5 - 4 / 5 of the diameter of the tower kettle.

[0018] A vertical baffle 103 is provided at the bottom of the tower kettle, and there are holes at the bottom of the vertical baffle 103.

[0019] The working fluid for producing hydrogen peroxide by the anthraquinone method includes a non-polar solvent, a polar solvent, and a working carrier. Among them, the non-polar solvent is heavy aromatic hydrocarbon, the polar solvent is one or a mixture of tributyl phosphate, tetrabutylurea, o-methylcyclohexyl acetate, and diisobutyl methanol, and the working carrier includes a mixture of one or more of 2-ethylanthraquinone, 2-butylanthraquinone, and 2-pentylanthraquinone.

[0020] Compared with the prior art, the present invention has the following beneficial effects: (1) The lipophilic fiber filaments are curved, and the bending radius is greater than the radius of the tower body. They are randomly and evenly intertwined in the upper section of the tower body. The mixing effect of the working fluid and the hydrogenated fluid is good, and uniform mixing of the working fluid and the hydrogenated fluid in the liquid film on the surface of the curved fiber filaments in the fiber membrane regeneration tower can be achieved, ensuring the regeneration effect of the degradation products. Moreover, there is no need to use a pipeline mixer and no new equipment needs to be added; (2) The lipophilic fiber filaments in the upper section of the tower body of the fiber membrane regeneration tower introduce the mixed working fluid into the middle section of the tower body. After being guided, the mixed working fluid flows stably, with little impact on the caustic soda liquid film on the surface of the hydrophilic fiber filaments in the middle section of the tower body, ensuring the stability of the oil-water two-phase liquid film, ensuring the effective utilization of the fiber filaments, and being beneficial to the regeneration of the degradation products; (3) Using caustic soda to treat the mixed solution of the working fluid and the hydrogenated fluid has a better regeneration effect than treating the working fluid or the hydrogenated fluid with caustic soda alone; (4) Using hydrophobic fiber filaments to introduce the mixed working fluid and caustic soda into the tower bottom ensures that the caustic soda enters the tower bottom in the form of a liquid film, which is beneficial to the rapid separation of the mixed working fluid and the caustic soda, and avoids the re-formation of a droplet-like dispersed state mixture of the oil-water two phases in the tower bottom; (5) The tower wall of the tower body extends deep into the tower bottom, and the lower edge of the tower wall of the tower body is 1 / 5 to 4 / 5 of the tower bottom diameter from the bottom of the tower bottom. Even if the oxygen generated by the decomposition of hydrogen peroxide forms an air cushion layer at the top of the tower bottom, the gas will not flow back into the tower body of the fiber membrane regeneration tower, effectively ensuring the stable liquid film flow state in the tower body; (6) The tower bottom is provided with a vertical baffle, and there are holes at the bottom of the vertical baffle. Further ensuring that the mixed working fluid and caustic soda flowing into the tower bottom will not affect the oil-water separation effect in the tower bottom. Brief Description of the Drawings

[0021] Figure 1 It is a fiber membrane regeneration tower for producing hydrogen peroxide by the anthraquinone method of the present invention; In the figure, 101 is the tower body, 1011 is the upper section of the tower body, 1012 is the middle section of the tower body, 1013 is the lower section of the tower body, 102 is the tower bottom, 103 is the vertical baffle, 01 is the working fluid inlet, 02 is the hydrogenated fluid inlet, 03 is the caustic soda inlet, 04 is the oil phase outlet, and 05 is the caustic soda outlet. Detailed Embodiments

[0022] A 200,000-ton / year (calculated at 27.5%) hydrogen peroxide production plant, the working fluid composition is: solvent (75 vol% C10 heavy aromatic hydrocarbon content, 15 vol% tributyl phosphate content, 10 vol% tetrabutylurea content) and working carrier (2-ethylanthraquinone, content is 160 g / L). The hydrogenated liquid and working fluid in the examples and comparative examples are from the above production plant, and the effective anthraquinone content in the working fluid and hydrogenated liquid is 160.0 g / L.

[0023] Example 1

[0024] The regeneration of the working fluid uses the fiber membrane regeneration tower of the present invention, which includes two parts: the tower body 101 and the tower kettle 102. The tower body 101 is vertical, the tower kettle 102 is horizontal, the bottom of the tower body 101 is open, the tower body 101 stands on the tower kettle 102, and the tower wall of the tower body 101 extends into the interior of the tower kettle 102; the tower body 101 is successively the upper tower section 1011, the middle tower section 1012, and the lower tower section 1013 from top to bottom. The upper tower section 1011 is filled with oil-loving fiber filaments, the middle tower section 1012 is filled with water-loving fiber filaments, and the lower tower section 1013 is filled with hydrophobic fiber filaments; a working fluid inlet 01 and a hydrogenated liquid inlet 02 are provided at the upper part of the upper tower section 1011, and an alkali liquid inlet 03 is provided at the top of the middle tower section 1012; an alkali liquid outlet 05 is provided at the bottom of the tower kettle 102, and an oil phase outlet 04 is provided at the top; a vertical baffle 103 is provided at the bottom of the tower kettle 102, and there are holes at the bottom of the vertical baffle 103.

[0025] After the hydrogenated liquid and the working fluid enter the fiber membrane regeneration tower from the upper part of the upper tower section, they flow downward, and are fully mixed under the action of the oil-loving fiber filaments in the upper tower section to form a mixed working fluid, and then enter the middle tower section. The alkali liquid enters the fiber membrane regeneration tower from the top of the middle tower section and adheres to the surface of the water-loving fiber filaments and flows downward. The mixed working fluid and the alkali liquid are fully contacted and reacted under the action of the water-loving fiber filaments in the middle tower section, and the degradation products in the mixed working fluid are regenerated. The mixed working fluid and the alkali liquid flow into the lower tower section of the fiber membrane regeneration tower together. After the mixed working fluid and the alkali liquid pass through the guiding action of the hydrophobic fiber filaments in the lower tower section, they enter the tower kettle of the fiber membrane regeneration tower, and the mixed working fluid and the alkali liquid are quickly separated in the tower kettle. The mixed working fluid flows out from the top of the tower kettle, and the alkali liquid flows out from the bottom of the tower kettle.

[0026] The liquid level of the tower body of the fiber membrane regeneration tower is controlled by controlling the outflow flow rate of the mixed working fluid at the top of the tower kettle.

[0027] The length of the upper tower section is 20% of the total length of the tower body, the length of the middle tower section is 73% of the total length of the tower body, and the length of the lower tower section is 7% of the total length of the tower body.

[0028] Both the water-loving fiber filaments and the hydrophobic fiber filaments are curved.

[0029] The oleophilic fibers are curved and evenly interwoven irregularly in the upper section of the tower body, and the ratio of the bending diameter to the tower body radius is 1.5.

[0030] The oleophilic fiber is made of stainless steel modified by a silane coupling agent, the hydrophilic fiber is made of stainless steel treated by electrochemical oxidation, and the hydrophobic fiber is made of polytetrafluoroethylene.

[0031] Working fluid flow rate 60m 3 / h, hydrogenation liquid flow rate 20m 3 / h, the flow ratio of working fluid to hydrogenation liquid is 3.

[0032] The mixed working fluid flow rate is 80m 3 / h, the alkali solution flow rate is 0.5 m 3 / h, the flow ratio of mixed working fluid to alkali solution is 160.

[0033] The alkali solution is a 40wt% potassium carbonate aqueous solution.

[0034] The distance between the lower edge of the tower wall of the tower body and the bottom of the tower kettle is 1 / 3 of the diameter of the tower kettle.

[0035] A sight glass installed in the upper section of the tower body reveals the uniform appearance of the mixed working solution and hydrogenation solution. The mixed working solution exiting the tower still contains 165.3 g / L of effective anthraquinone. The alkalinity of the mixed working solution is 2-3 mg / L (calculated as potassium carbonate).

[0036] Example 2

[0037] The length of the upper section of the tower body is 15% of the total length of the tower body, the length of the middle section of the tower body is 77% of the total length of the tower body, and the length of the lower section of the tower body is 8% of the total length of the tower body. The ratio of the bending diameter of the oleophilic fiber to the radius of the tower body is 1.7.

[0038] The oleophilic fiber is made of polyvinylidene fluoride, the hydrophilic fiber is made of stainless steel modified by acrylic acid grafting, and the hydrophobic fiber is made of stainless steel modified by siloxane chemical vapor deposition.

[0039] Working fluid flow rate 60m 3 / h, hydrogenation liquid flow rate 10m 3 / h, the ratio of working fluid to hydrogenated fluid flow is 6. The mixed working fluid flow is 70m 3 / h, the alkali solution flow rate is 0.35 m 3 / h, the flow ratio of mixed working fluid to alkali solution is 200.

[0040] The alkali solution is a mixture of 40 wt % potassium carbonate aqueous solution and 2 wt % sodium hydroxide aqueous solution.

[0041] The distance between the lower edge of the tower wall of the tower body and the bottom of the tower kettle is 1 / 2 of the diameter of the tower kettle.

[0042] The remaining operations are the same as those in Example 1.

[0043] Through the sight glass installed in the upper section of the tower body, it can be observed that the appearance of the working fluid and the hydrogenated fluid is uniform after mixing. The effective anthraquinone content in the mixed working fluid flowing out from the bottom of the tower is 163.8 g / L. The alkalinity of the mixed working fluid is 3 - 4 mg / L (calculated as potassium carbonate).

[0044] Example 3

[0045] The length of the upper section of the tower body is 10% of the total length of the tower body, the length of the middle section of the tower body is 80% of the total length of the tower body, and the length of the lower section of the tower body is 10% of the total length of the tower body. The ratio of the bending diameter of the oilophilic fiber filaments to the radius of the tower body is 2.

[0046] The material of the oilophilic fiber filaments is stainless steel modified with silane coupling agent, the material of the hydrophilic fiber filaments is stainless steel modified with polyvinyl alcohol, and the material of the hydrophobic fiber filaments is stainless steel by electrochemical etching.

[0047] The flow rate of the working fluid is 60 m 3 / h, the flow rate of the hydrogenated fluid is 6 m 3 / h, and the flow rate ratio of the working fluid to the hydrogenated fluid is 10. The flow rate of the mixed working fluid is 66 m 3 / h, the flow rate of the lye is 0.066 m 3 / h, and the flow rate ratio of the mixed working fluid to the lye is 1000.

[0048] The lye is a 5 wt% aqueous sodium hydroxide solution.

[0049] The distance between the lower edge of the tower wall of the tower body and the bottom of the tower kettle is 4 / 5 of the diameter of the tower kettle.

[0050] The remaining operations are the same as those in Example 1.

[0051] Through the sight glass installed in the upper section of the tower body, it can be observed that the appearance of the working fluid and the hydrogenated fluid is uniform after mixing. The effective anthraquinone content in the mixed working fluid flowing out from the bottom of the tower is 164.2 g / L. The alkalinity of the mixed working fluid is 1 - 2 mg / L (calculated as potassium carbonate).

[0052] Example 4

[0053] The length of the upper section of the tower body is 30% of the total length of the tower body, the length of the middle section of the tower body is 65% of the total length of the tower body, and the length of the lower section of the tower body is 5% of the total length of the tower body. The ratio of the bending diameter of the oilophilic fiber filaments to the radius of the tower body is 1.3.

[0054] The material of the oilophilic fiber filaments is polystyrene, the material of the hydrophilic fiber filaments is stainless steel by electrochemical oxidation treatment, and the material of the hydrophobic fiber filaments is stainless steel modified by silicon oxide chemical vapor deposition.

[0055] The flow rate of the working fluid is 60 m 3 / h, and the flow rate of the hydrogenated liquid is 60 m 3 / h. The ratio of the flow rate of the working fluid to the hydrogenated liquid is 1. The flow rate of the mixed working fluid is 120 m 3 / h, and the flow rate of the lye is 0.06 m 3 / h. The ratio of the flow rate of the mixed working fluid to the lye is 2000.

[0056] The lye is a mixture of 40 wt% potassium carbonate aqueous solution and 5 wt% sodium hydroxide aqueous solution.

[0057] The distance between the lower edge of the tower wall of the tower body and the bottom of the tower kettle is 1 / 5 of the diameter of the tower kettle.

[0058] The rest of the operations are the same as in Example 1.

[0059] Through the sight glass set in the upper section of the tower body, it can be observed that the appearance of the working fluid and the hydrogenated liquid is uniform after mixing. The effective anthraquinone content in the mixed working fluid flowing out of the tower kettle is 162.8 g / L. The alkalinity of the mixed working fluid is 1 - 3 mg / L (calculated as potassium carbonate).

[0060] Example 5

[0061] The length of the upper section of the tower body is 25% of the total length of the tower body, the length of the middle section of the tower body is 69% of the total length of the tower body, and the length of the lower section of the tower body is 6% of the total length of the tower body. The ratio of the bending diameter of the oil - loving fiber filaments to the radius of the tower body is 1.

[0062] The material of the oil - loving fiber filaments is polyvinylidene fluoride, the material of the hydrophilic fiber filaments is electrochemically oxidized stainless steel, and the material of the hydrophobic fiber filaments is polytetrafluoroethylene.

[0063] The flow rate of the working fluid is 60 m 3 / h, and the flow rate of the hydrogenated liquid is 6 m 3 / h. The ratio of the flow rate of the working fluid to the hydrogenated liquid is 10.

[0064] The flow rate of the mixed working fluid is 66 m 3 / h, and the flow rate of the lye is 3.3 m 3 / h. The ratio of the flow rate of the mixed working fluid to the lye is 20.

[0065] The lye is a mixture of 35 wt% potassium carbonate aqueous solution and 5 wt% sodium hydroxide aqueous solution.

[0066] The distance between the lower edge of the tower wall of the tower body and the bottom of the tower kettle is 2 / 5 of the diameter of the tower kettle.

[0067] No vertical baffle is installed in the tower kettle.

[0068] The rest is the same as in Example 1.

[0069] The appearance of the mixed working fluid and hydrogenated fluid is uniform as observed through the sight glass installed in the upper section of the tower body. The effective anthraquinone content in the mixed working fluid flowing out from the bottom of the tower is 163.5 g / L. The alkalinity of the mixed working fluid is 3.5 - 5.0 mg / L (calculated as potassium carbonate).

[0070] Example 6

[0071] The length of the upper section of the tower body is 15% of the total length of the tower body, the length of the middle section of the tower body is 76% of the total length of the tower body, and the length of the lower section of the tower body is 9% of the total length of the tower body. The ratio of the bending diameter of the oilophilic fiber filaments to the radius of the tower body is 1.8.

[0072] The material of the oilophilic fiber filaments is stainless steel modified with silane coupling agent, the material of the hydrophilic fiber filaments is stainless steel treated by electrochemical oxidation, and the material of the hydrophobic fiber filaments is polytetrafluoroethylene.

[0073] The flow rate of the working fluid is 60 m 3 / h, the flow rate of the hydrogenated fluid is 6 m 3 / h, and the ratio of the flow rate of the working fluid to the flow rate of the hydrogenated fluid is 10.

[0074] The flow rate of the mixed working fluid is 66 m 3 / h, the flow rate of the lye is 1.1 m 3 / h, and the ratio of the flow rate of the mixed working fluid to the flow rate of the lye is 60.

[0075] The lye is a mixture of 35 wt% aqueous potassium carbonate solution and 1 wt% aqueous sodium hydroxide solution.

[0076] The distance between the lower edge of the tower wall of the tower body and the bottom of the tower kettle is 3 / 5 of the diameter of the tower kettle.

[0077] The rest is the same as in Example 1.

[0078] The appearance of the mixed working fluid and hydrogenated fluid is uniform as observed through the sight glass installed in the upper section of the tower body. The effective anthraquinone content in the working fluid is 160.0 g / L, and the effective anthraquinone content in the mixed working fluid flowing out from the bottom of the tower is 162.8 g / L. The alkalinity of the mixed working fluid is 1 - 4 mg / L (calculated as potassium carbonate).

[0079] Comparative Example 1

[0080] The upper section of the tower body is filled with hydrophilic fiber filaments, the middle section of the tower body is filled with hydrophilic fiber filaments, and the lower section of the tower body is filled with hydrophobic fiber filaments. The hydrophilic fiber filaments in the upper section of the tower body are curved and are randomly and evenly intertwined in the upper section of the tower body. The ratio of the bending diameter to the radius of the tower body is 1.5. After the working fluid and the hydrogenated fluid are mixed through a static mixer, they enter the fiber membrane regeneration tower from the working fluid inlet in the upper section of the tower body, and the lye enters the fiber membrane regeneration tower from the upper part of the upper section of the tower body. The material of the hydrophilic fiber filaments is stainless steel treated by electrochemical oxidation, and the material of the hydrophobic fiber filaments is polytetrafluoroethylene. The rest is the same as in Example 1.

[0081] Through the sight glass installed in the upper section of the tower body, obvious local appearance non-uniformity can be observed (the working fluid is yellow and the hydrogenated fluid is black). The effective anthraquinone content in the mixed working fluid flowing out from the bottom of the tower is 161.5 g / L. The alkalinity of the mixed working fluid is 3 - 8 mg / L (calculated as potassium carbonate).

[0082] Comparative Example 2

[0083] The upper section of the tower body is filled with lipophilic fiber filaments, the middle section of the tower body is filled with hydrophilic fiber filaments, and the lower section of the tower body is filled with hydrophilic fiber filaments. The lipophilic fiber filaments are made of stainless steel modified with silane coupling agent, and the hydrophilic fiber filaments are made of stainless steel treated by electrochemical oxidation. The rest is the same as in Example 1.

[0084] Through the sight glass installed in the upper section of the tower body, it can be observed that the appearance is uniform after the working fluid and the hydrogenated fluid are mixed. The effective anthraquinone content in the mixed working fluid flowing out from the bottom of the tower is 165.0 g / L. The oil-water two-phase interface in the bottom of the tower will fluctuate, and the alkalinity of the mixed working fluid is 3 - 10 mg / L (calculated as potassium carbonate).

[0085] Comparative Example 3

[0086] Only the working fluid is introduced into the fiber membrane regeneration tower, and the hydrogenated fluid is not introduced. The rest is the same as in Example 1.

[0087] The effective anthraquinone content in the mixed working fluid flowing out from the bottom of the tower is 161.0 g / L. The alkalinity of the mixed working fluid is 2 - 4 mg / L (calculated as potassium carbonate).

[0088] Comparative Example 4

[0089] The ratio of the bending diameter of the lipophilic fiber filaments to the radius of the tower body is 0.9. The rest is the same as in Example 1.

[0090] Through the sight glass installed in the upper section of the tower body, it can be observed that there is a slight non-uniformity in the appearance after the working fluid and the hydrogenated fluid are mixed. The effective anthraquinone content in the mixed working fluid flowing out from the bottom of the tower is 162.2 g / L. The alkalinity of the mixed working fluid is 2 - 4 mg / L (calculated as potassium carbonate).

[0091] Comparative Example 5

[0092] The ratio of the bending diameter of the lipophilic fiber filaments to the radius of the tower body is 2.5. The rest is the same as in Example 1.

[0093] Through the sight glass installed in the upper section of the tower body, it can be observed that there is a slight non-uniformity in the appearance after the working fluid and the hydrogenated fluid are mixed. The effective anthraquinone content in the mixed working fluid flowing out from the bottom of the tower is 162.1 g / L. The alkalinity of the mixed working fluid is 2 - 4 mg / L (calculated as potassium carbonate).

[0094] From the operating data of the above examples and comparative examples, it can be seen that using a mixed solution of hydrogenated liquid and working liquid for alkali treatment regeneration improves the regeneration effect. In the examples, the upper section of the tower is filled with oil-loving fiber filaments, the middle section of the tower is filled with water-loving fiber filaments, and the lower section of the tower is filled with hydrophobic fiber filaments. The oil-loving fiber filaments in the upper section of the tower promote the uniform mixing of the hydrogenated liquid and the working liquid, and slow down the impact of the mixed working liquid on the alkali solution, which is beneficial to the non-dispersed contact between the mixed working liquid and the alkali solution, beneficial to the regeneration of degradation products, and also beneficial to the rapid separation of the working liquid and the alkali solution; the hydrophobic fiber filaments filled in the lower section of the tower are beneficial to the separation of the mixed working liquid and the alkali solution, and the alkalinity of the mixed working liquid is relatively low. The bending radius of the oil-loving fiber filaments in the upper section of the tower is within a suitable range, which promotes the uniform mixing of the hydrogenated liquid and the working liquid.

[0095] When using a static mixer, since the upper section of the tower is not filled with oil-loving fiber filaments, the mixing of the hydrogenated liquid and the working liquid is poor, and the regeneration effect of the degradation products is average; the impact of the mixed working liquid on the alkali solution is strong, resulting in the alkalinity of the mixed working liquid discharged from the tower bottom being prone to exceed the standard (the index ≤ 4 mg / L, calculated as potassium carbonate), and the fluctuation is relatively large.

Claims

1. A fiber membrane regeneration tower for the production of hydrogen peroxide by the anthraquinone process, characterized in that, It consists of two parts, namely a tower body (101) and a tower bottom (102). The tower body (101) is vertical, and the tower bottom (102) is horizontal. The bottom of the tower body (101) is open, and the tower body (101) stands on the tower bottom (102), with the tower wall of the tower body (101) extending into the interior of the tower bottom (102). The tower body (101) is successively divided into an upper tower body section (1011), a middle tower body section (1012), and a lower tower body section (1013) from top to bottom. The upper tower body section (1011) is filled with oil-loving fiber filaments, the middle tower body section (1012) is filled with water-loving fiber filaments, and the lower tower body section (1013) is filled with water-repellent fiber filaments. At the upper part of the upper tower body section (1011), a working fluid inlet (01) and a hydrogenated liquid inlet (02) are provided, and at the top of the middle tower body section (1012), an alkali solution inlet (03) is provided. At the bottom of the tower bottom (102), an alkali solution outlet (05) is provided, and at the top, an oil phase outlet (04) is provided.

2. The fiber membrane regeneration tower according to claim 1, wherein The length of the upper tower body section (1011) is 10% - 30% of the total length of the tower body, the length of the middle tower body section (1012) is 60% - 85% of the total length of the tower body, and the length of the lower tower body section (1013) is 5% - 10% of the total length of the tower body.

3. The fiber membrane regeneration tower according to claim 1, characterized in that, The oil-loving fiber filaments, water-loving fiber filaments, and water-repellent fiber filaments are all in a curved shape.

4. The fiber membrane regeneration tower according to claim 1, wherein, The oil-loving fiber filaments are randomly and evenly intertwined in the upper tower body section, and the ratio of the bending diameter of the oil-loving fiber filaments to the radius of the tower body is 1 - 2.

5. The fiber membrane regeneration tower according to claim 1, wherein The material of the oil-loving fiber filaments is one of polyvinylidene fluoride, polystyrene, and stainless steel modified with silane coupling agent; the material of the water-loving fiber filaments is one of stainless steel treated by electrochemical oxidation, stainless steel grafted with acrylic acid, and stainless steel modified with polyvinyl alcohol; the material of the water-repellent fiber filaments is one of polytetrafluoroethylene, stainless steel modified by chemical vapor deposition of siloxane, and stainless steel treated by electrochemical etching.

6. The fiber membrane regeneration tower according to claim 1, characterized in that, The volume flow ratio of the working fluid to the hydrogenated liquid is 10 - 1.

7. The fiber membrane regeneration tower according to claim 1, wherein The working fluid and the hydrogenated liquid are fully mixed under the action of the oil-loving fiber filaments in the upper tower body section (1011) to form a mixed working fluid, and the volume flow ratio of the mixed working fluid to the alkali solution is 2000 - 20.

8. The fiber membrane regeneration tower according to claim 1, wherein, The alkali solution is an aqueous solution of one or more substances among sodium hydroxide, potassium carbonate, potassium hydroxide, and sodium carbonate.

9. The fiber membrane regeneration tower according to claim 1, wherein The distance between the bottom of the tower body and the bottom of the tower bottom is 1 / 5 - 4 / 5 of the diameter of the tower bottom.

10. The fiber membrane regeneration tower according to claim 1, characterized in that, A vertical baffle (103) is provided at the bottom of the tower bottom, and there are holes at the bottom of the vertical baffle (103).

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