A fiber membrane regeneration tower for producing hydrogen peroxide using anthraquinone method

Abstract

The present invention discloses a fiber membrane regeneration tower for producing hydrogen peroxide by an anthraquinone process, comprising a tower body and a tower kettle. The tower body is vertical, the tower kettle is horizontal, the tower body has an opening at the bottom, the tower body stands on the tower kettle, and the tower wall of the tower body extends deep into the tower kettle; the tower body is divided into an upper section, a middle section, and a lower section from top to bottom, the upper section is filled with oleophilic fiber filaments, the middle section is filled with hydrophilic fiber filaments, and the lower section is filled with hydrophobic fiber filaments; the upper part of the upper section of the tower body is provided with a working liquid inlet and a hydrogenation liquid inlet, the top of the middle section of the tower body is provided with an alkali liquid inlet; the bottom of the tower kettle is provided with an alkali liquid outlet, and the top is provided with an oil phase outlet. The fiber membrane regeneration tower achieves the effects of stable liquid film, efficient mixing, good regeneration effect, rapid separation, etc. by filling the upper section with oleophilic fiber filaments, the middle section with hydrophilic fiber filaments, and the lower section with hydrophobic fiber filaments.

Description

Technical Field

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

[0002] Hydrogen peroxide is a green oxidant widely used in the chemical industry. Currently, hydrogen peroxide is generally produced industrially using the anthraquinone process. In this process, a carrier and solvent are combined in a specific ratio to form a working fluid. Typically, the carrier is 2-ethylanthraquinone, 2-butylanthraquinone, 2-pentylanthraquinone, or a mixture thereof, and the solvent is a mixture of heavy aromatic hydrocarbons, trioctyl phosphate, o-methylcyclohexyl acetate, diisobutylcarbinol, and tetrabutylurea. The working fluid circulates through the system in the order of hydrogenation, oxidation, extraction, and post-processing, producing hydrogen peroxide. In the hydrogenation step, the working fluid undergoes a hydrogenation reaction over a catalyst to produce a hydrogenated solution. In the oxidation step, the hydrogenated solution reacts with oxygen to produce an oxidized solution. In the extraction step, the hydrogen peroxide in the oxidized solution is extracted with water to produce a hydrogen peroxide aqueous solution (extract). After dehydration, hydrogen peroxide removal, and degradation product regeneration in the post-processing step, the working fluid enters the circulating working fluid storage tank, completing the cycle.

[0003] During the continuous hydrogenation and oxidation reactions of the working fluid, the solvent and alkylanthraquinone degrade, producing substances such as carboxylic acids, phenols, and aldehydes (JP6428622B2). This alters the working fluid's physical properties and, in severe cases, can affect the proper operation of the extraction tower. Treating the working fluid with an alkaline solution (typically an aqueous solution of potassium carbonate or sodium hydroxide) can remove or regenerate degradation products and reduce their content. For example, if the working fluid passes through a drying tower filled with potassium carbonate or an alkaline washing tower filled with sodium hydroxide, some of the degradation products are regenerated into effective anthraquinone, while others dissolve in the alkaline solution and are carried out of the system.

[0004] Fiber membrane technology can enhance mass transfer between the alkali solution and the working fluid (CN114180773A). In the fiber membrane regeneration tower, the working fluid and the alkali solution form a liquid film-like, non-dispersed mass transfer, resulting in low liquid holdup and excellent regeneration efficiency. However, in the front section of the fiber membrane regeneration tower, the working fluid experiences strong impact and turbulence, preventing the alkali solution from stably adhering to the fiber surface to form a liquid film. This creates a poor contact zone between the oil and water phases in the front section of the fiber membrane regeneration tower, leading to waste of fiber in this area.

[0005] Under alkaline conditions, the epoxyanthraquinones in anthraquinone degradation products can be regenerated into effective anthraquinones with the presence of alkylanthrahydroquinones. Therefore, mixing the working solution with the hydrogenation solution and subjecting them to a regeneration treatment with an alkaline solution, such as alkali solution and activated alumina, can enhance the regeneration of the degradation products. The alkylanthraquinones in the working and hydrogenation solutions contain relatively large molecular weights, making simple mechanical mixing inadequate. Appropriate means are required to achieve uniform mixing of the two phases to promote regeneration. External equipment (such as pipeline mixers and stirred tanks) is generally required to achieve uniform mixing of the working solution, hydrogenation solution, and alkali solution. This additional equipment complicates control and does not guarantee effective mixing. Summary of the Invention

[0006] To solve the above problems, the present invention proposes a fiber membrane regeneration tower for producing hydrogen peroxide using the anthraquinone method. The fiber membrane regeneration tower uses oleophilic fiber filaments to guide the working fluid and hydrogenation liquid to the middle section of the tower body, thereby reducing the impact of the alkaline liquid film on the surface of the hydrophilic fiber filaments; the curved and interwoven oleophilic fiber filaments achieve uniform mixing of the working fluid and the hydrogenation liquid without the need for additional equipment; the provision of hydrophobic fiber filaments accelerates oil-water separation; the tower body structure is designed to prevent gas backflow, and the tower kettle baffle ensures oil-water stratification; it has the advantages of stable liquid film, efficient mixing, good regeneration effect, and rapid separation.

[0007] The technical solutions of the present invention are as follows:

[0008] A fiber membrane regeneration tower for producing hydrogen peroxide using an anthraquinone process comprises a tower body 101 and a tower bottom 102. The tower body 101 is vertical and the tower bottom 102 is horizontal. The tower body 101 has an open bottom and stands on the tower bottom 102. The tower wall of the tower body 101 extends deep into the tower bottom 102.

[0009] The tower body 101 is composed of an upper section 1011, a middle section 1012 and a lower section 1013 from top to bottom. The upper section 1011 is filled with oleophilic fibers, the middle section 1012 is filled with hydrophilic fibers, and the lower section 1013 is filled with hydrophobic fibers.

[0010] The upper part of the tower body upper section 1011 is provided with a working liquid inlet 01 and a hydrogenation liquid inlet 02, and the top of the tower body middle section 1012 is provided with an alkali liquid inlet 03;

[0011] The bottom of the tower kettle 102 is provided with an alkali liquid outlet 05, and the top is provided with an oil phase outlet 04.

[0012] After the hydrogenation liquid and working liquid enter the fiber membrane regeneration tower from the upper section of the tower, they flow downward and are thoroughly mixed by the oleophilic fibers in the upper section, forming a mixed working liquid that then enters the middle section. Alkaline solution enters the fiber membrane regeneration tower from the top of the middle section, adheres to the surface of the hydrophilic fibers, and flows downward. The mixed working liquid and alkali solution fully contact and react with each other under the action of the hydrophilic fibers in the middle section, regenerating the degradation products in the mixed working liquid. The mixed working liquid and alkali solution then flow together into the lower section of the fiber membrane regeneration tower. After being guided by the hydrophobic fibers in the lower section, the mixed working liquid and alkali solution enter the lower section of the fiber membrane regeneration tower, where they are rapidly separated. The mixed working liquid flows out from the top of the lower section, while the alkali solution flows out from the bottom.

[0013] The liquid level of the fiber membrane regeneration tower body is controlled by controlling the outflow rate of the mixed working liquid at the top of the tower kettle.

[0014] The length of the upper section 1011 of the tower body is 10% to 30% of the total length of the tower body, preferably 15%, 20%, or 25%; the length of the middle section 1012 of the tower body is 60% to 85% of the total length of the tower body, preferably 65%, 75%, or 80%; the length of the lower section 1013 of the tower body is 5% to 10% of the total length of the tower body, preferably 7% to 9%.

[0015] The oleophilic fiber yarns, hydrophilic fiber yarns and hydrophobic fiber yarns are all curved.

[0016] The oleophilic fiber filaments are randomly and evenly interwoven in the upper section of the tower body, and the ratio of the bending diameter of the oleophilic fiber filaments to the radius of the tower body is 1-2.

[0017] The oleophilic fiber material is one of polyvinylidene fluoride, polystyrene, and stainless steel modified by silane coupling agent; the hydrophilic fiber material is one of stainless steel treated by electrochemical oxidation, stainless steel modified by acrylic acid grafting, and stainless steel modified by polyvinyl alcohol; the hydrophobic fiber material is one of polytetrafluoroethylene, stainless steel modified by siloxane chemical vapor deposition, and stainless steel modified by electrochemical etching.

[0018] The volume flow ratio of the working fluid to the hydrogenation fluid is 10-1.

[0019] The volume flow ratio of the mixed working liquid to the alkali solution is 2000~20.

[0020] The alkali solution is an aqueous solution of one or more substances selected from the group consisting of sodium hydroxide, potassium carbonate, potassium hydroxide, and sodium carbonate.

[0021] The distance between the bottom of the tower body and the bottom of the tower kettle is 1 / 5 to 4 / 5 of the diameter of the tower kettle.

[0022] A vertical baffle 103 is provided at the bottom of the tower kettle, and a hole is provided at the bottom of the vertical baffle 103 .

[0023] The working fluid for producing hydrogen peroxide by the anthraquinone process includes a non-polar solvent, a polar solvent, and a working carrier. The non-polar solvent is a heavy aromatic hydrocarbon, the polar solvent is a mixture of one or more of trioctyl phosphate, tetrabutyl urea, o-methylcyclohexyl acetate, and diisobutyl carbinol, and the working carrier includes a mixture of one or more of 2-ethylanthraquinone, 2-butylanthraquinone, and 2-amylanthraquinone.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The oleophilic fiber filaments are curved, with a bending radius greater than the radius of the tower body. They are evenly interwoven in the upper part of the tower body. The mixing effect of the working liquid and the hydrogenation liquid is good, and the working liquid and the hydrogenation liquid can be evenly mixed in the liquid film on the surface of the curved fiber filaments in the fiber membrane regeneration tower, ensuring the regeneration effect of the degradation products. There is no need to use a pipeline mixer and no need for additional equipment;

[0026] (2) The oleophilic fiber filaments in the upper part of the fiber membrane regeneration tower guide the mixed working liquid into the middle part of the tower. After the mixed working liquid is guided, it flows stably and has little impact on the alkaline liquid film on the surface of the hydrophilic fiber filaments in the middle part of the tower, thus ensuring the stability of the oil-water two-phase liquid film and the effective utilization of the fiber filaments, which is conducive to the regeneration of the degraded products.

[0027] (3) The regeneration effect of treating the mixed solution of working solution and hydrogenation solution with alkali solution is better than that of treating the working solution or hydrogenation solution with alkali solution alone;

[0028] (4) Using hydrophobic fiber to introduce the mixed working liquid and alkali solution into the tower kettle, ensuring that the alkali solution enters the tower kettle in the form of a liquid film, which is conducive to the rapid separation of the mixed working liquid and the alkali solution, and avoids the oil-water two phases from forming a droplet-like dispersion state in the tower kettle again;

[0029] (5) The tower wall extends deep into the tower kettle, and the lower edge of the tower wall is 1 / 5 to 4 / 5 of the tower kettle diameter away from the bottom of the tower kettle. Even if the oxygen generated by the decomposition of hydrogen peroxide forms an air cushion layer at the top of the tower kettle, the gas will not flow back into the fiber membrane regeneration tower body, effectively ensuring a stable liquid film flow state in the tower body;

[0030] (6) The tower kettle is equipped with a vertical baffle with a hole at the bottom to further ensure that the mixed working fluid and alkali solution flowing into the tower kettle will not affect the oil-water stratification effect in the tower kettle. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a fiber membrane regeneration tower for producing hydrogen peroxide by the anthraquinone method of the present invention;

[0032] In the figure, 101 is the tower body, 1011 is the upper part of the tower body, 1012 is the middle part of the tower body, 1013 is the lower part of the tower body, 102 is the tower kettle, 103 is the vertical baffle, 01 is the working liquid inlet, 02 is the hydrogenation liquid inlet, 03 is the alkali liquid inlet, 04 is the oil phase outlet, and 05 is the alkali liquid outlet. DETAILED DESCRIPTION

[0033] The working fluid composition of a 200,000 tons / year (27.5% hydrogen peroxide) hydrogen peroxide production unit consists of a solvent (75 vol% C10 heavy aromatics, 15 vol% trioctyl phosphate, and 10 vol% tetrabutyl urea) and a working carrier (2-ethylanthraquinone, 160 g / L). The hydrogenation liquid and working fluid used in the Examples and Comparative Examples were obtained from the aforementioned production unit. The effective anthraquinone content in both the working and hydrogenation liquids was 160.0 g / L.

[0034] Example 1

[0035] The fiber membrane regeneration tower of the present invention is used for the regeneration of the working fluid, which comprises 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. The tower wall of the tower body 101 penetrates into the interior of the tower bottom 102. The tower body 101 is composed of an upper tower section 1011, a middle tower section 1012 and a lower tower section 1013 from top to bottom. The upper tower section 1011 is filled with pro The tower body is provided with oil fiber filaments, the middle section 1012 of the tower body is filled with hydrophilic fiber filaments, and the lower section 1013 of the tower body is filled with hydrophobic fiber filaments; the upper part of the upper section 1011 of the tower body is provided with a working liquid inlet 01 and a hydrogenation liquid inlet 02, and the top of the middle section 1012 of the tower body is provided with an alkali liquid inlet 03; the bottom of the tower kettle 102 is provided with an alkali liquid outlet 05, and the top is provided with an oil phase outlet 04; the bottom of the tower kettle 102 is provided with a vertical baffle 103, and the bottom of the vertical baffle 103 has a hole.

[0036] After the hydrogenated liquid and working liquid enter the fiber membrane regeneration tower from the upper section of the tower, they flow downward and are thoroughly mixed by the oleophilic fibers in the upper section, forming a mixed working liquid that then enters the middle section. Alkaline solution enters the fiber membrane regeneration tower from the top of the middle section, adheres to the surface of the hydrophilic fibers, and flows downward. The mixed working liquid and alkali solution fully contact and react with each other under the action of the hydrophilic fibers in the middle section, regenerating the degradation products in the mixed working liquid. The mixed working liquid and alkali solution then flow together into the lower section of the fiber membrane regeneration tower. After being guided by the hydrophobic fibers in the lower section, the mixed working liquid and alkali solution enter the lower section of the fiber membrane regeneration tower, where they are rapidly separated. The mixed working liquid flows out from the top of the lower section, while the alkali solution flows out from the bottom.

[0037] The liquid level of the fiber membrane regeneration tower body is controlled by controlling the outflow rate of the mixed working liquid at the top of the tower kettle.

[0038] The length of the upper section of the tower body is 20% of the total length of the tower body, the length of the middle section of the tower body is 73% of the total length of the tower body, and the length of the lower section of the tower body is 7% of the total length of the tower body.

[0039] Both the hydrophilic fiber filaments and the hydrophobic fiber filaments are curved.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] The alkali solution is a 40wt% potassium carbonate aqueous solution.

[0045] 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.

[0046] 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).

[0047] Example 2

[0048] 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.

[0049] 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.

[0050] 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.

[0051] The alkali solution is a mixture of 40 wt % potassium carbonate aqueous solution and 2 wt % sodium hydroxide aqueous solution.

[0052] 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.

[0053] The remaining operations are the same as in Example 1.

[0054] 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 163.8 g / L of effective anthraquinone. The alkalinity of the mixed working solution is 3-4 mg / L (calculated as potassium carbonate).

[0055] Example 3

[0056] 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 oleophilic fiber to the radius of the tower body is 2.

[0057] The oleophilic fiber is made of stainless steel modified with silane coupling agent, the hydrophilic fiber is made of stainless steel modified with polyvinyl alcohol, and the hydrophobic fiber is made of electrochemically etched stainless steel.

[0058] Working fluid flow rate 60m 3 / h, hydrogenation liquid flow rate 6m 3 / h, the ratio of working fluid to hydrogenated fluid flow is 10. The mixed working fluid flow is 66m 3 / h, the alkali solution flow rate is 0.066 m 3 / h, the flow ratio of mixed working fluid to alkali solution is 1000.

[0059] The alkali solution is a 5wt% sodium hydroxide aqueous solution.

[0060] 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.

[0061] The remaining operations are the same as in Example 1.

[0062] 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 164.2 g / L of effective anthraquinone. The alkalinity of the mixed working solution is 1-2 mg / L (calculated as potassium carbonate).

[0063] Example 4

[0064] 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 oleophilic fiber to the radius of the tower body is 1.3.

[0065] The oleophilic fiber is made of polystyrene, the hydrophilic fiber is made of stainless steel treated by electrochemical oxidation, and the hydrophobic fiber is made of stainless steel modified by siloxane chemical vapor deposition.

[0066] Working fluid flow rate 60m 3 / h, hydrogenation liquid flow rate 60m 3 / h, the ratio of working fluid to hydrogenated fluid flow is 1. The mixed working fluid flow is 120m 3 / h, the alkali solution flow rate is 0.06 m 3 / h, the flow ratio of mixed working fluid to alkali solution is 2000.

[0067] The alkali solution is a mixture of 40 wt % potassium carbonate aqueous solution and 5 wt % sodium hydroxide aqueous solution.

[0068] 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.

[0069] The remaining operations are the same as in Example 1.

[0070] 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 162.8 g / L of effective anthraquinone. The alkalinity of the mixed working solution is 1-3 mg / L (calculated as potassium carbonate).

[0071] Example 5

[0072] 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 oleophilic fiber to the radius of the tower body is 1.

[0073] The oleophilic fiber is made of polyvinylidene fluoride, the hydrophilic fiber is made of electrochemically oxidized stainless steel, and the hydrophobic fiber is made of polytetrafluoroethylene.

[0074] Working fluid flow rate 60m 3 / h, hydrogenation liquid flow rate 6m 3 / h, the flow ratio of working fluid to hydrogenation liquid is 10.

[0075] The mixed working fluid flow rate is 66m 3 / h, the alkali solution flow rate is 3.3 m 3 / h, the flow ratio of mixed working fluid to alkali solution is 20.

[0076] The alkali solution is a mixture of 35 wt % potassium carbonate aqueous solution and 5 wt % sodium hydroxide aqueous solution.

[0077] 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.

[0078] The tower kettle is not provided with a vertical baffle.

[0079] The rest is the same as Example 1.

[0080] 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 163.5 g / L of effective anthraquinone. The alkalinity of the mixed working solution is 3.5-5.0 mg / L (calculated as potassium carbonate).

[0081] Example 6

[0082] 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 oleophilic fiber to the tower body radius is 1.8.

[0083] The oleophilic fiber is made of stainless steel modified with silane coupling agent, the hydrophilic fiber is made of stainless steel treated with electrochemical oxidation, and the hydrophobic fiber is made of polytetrafluoroethylene.

[0084] Working fluid flow rate 60m 3 / h, hydrogenation liquid flow rate 6m 3 / h, the flow ratio of working fluid to hydrogenation liquid is 10.

[0085] The mixed working fluid flow rate is 66m 3 / h, the alkali solution flow rate is 1.1 m 3 / h, the flow ratio of mixed working fluid to alkali solution is 60.

[0086] The alkali solution is a mixture of 35 wt % potassium carbonate aqueous solution and 1 wt % sodium hydroxide aqueous solution.

[0087] 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.

[0088] The rest is the same as Example 1.

[0089] 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 effective anthraquinone content in the working solution is 160.0 g / L, and the effective anthraquinone content in the mixed working solution flowing out of the tower bottom is 162.8 g / L. The alkalinity of the mixed working solution is 1-4 mg / L (calculated as potassium carbonate).

[0090] Comparative Example 1

[0091] 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 evenly interwoven in a random pattern in the upper section of the tower body. The ratio of the bending diameter to the tower body radius is 1.5. After the working fluid and the hydrogenated liquid are mixed in a static mixer, they enter the fiber membrane regeneration tower through the working fluid inlet of the upper section of the tower body, and the alkali solution enters the fiber membrane regeneration tower from the upper part of the upper section of the tower body. The hydrophilic fiber filaments are made of stainless steel treated by electrochemical oxidation, and the hydrophobic fiber filaments are made of polytetrafluoroethylene. The rest is the same as in Example 1.

[0092] A sight glass installed in the upper section of the tower reveals significant localized unevenness (the working fluid is yellow, the hydrogenation fluid is black). The mixed working fluid exiting the tower kettle contains 161.5 g / L of effective anthraquinone. The alkalinity of the mixed working fluid is 3-8 mg / L (calculated as potassium carbonate).

[0093] Comparative Example 2

[0094] The upper section of the tower body is filled with oleophilic fiber, the middle section is filled with hydrophilic fiber, and the lower section is filled with hydrophilic fiber. The oleophilic fiber is made of stainless steel modified with a silane coupling agent, and the hydrophilic fiber is made of stainless steel treated with electrochemical oxidation. The rest is the same as in Example 1.

[0095] A sight glass installed in the upper section of the tower body reveals the uniform appearance of the mixed working liquid and hydrogenation liquid. The mixed working liquid exiting the tower kettle contains 165.0 g / L of effective anthraquinone. Fluctuations occur at the oil-water interface within the tower kettle, and the alkalinity of the mixed working liquid ranges from 3 to 10 mg / L (calculated as potassium carbonate).

[0096] Comparative Example 3

[0097] Only the working liquid was introduced into the fiber membrane regeneration tower, and no hydrogenation liquid was introduced.

[0098] The effective anthraquinone content of the mixed working liquid flowing out of the tower bottom is 161.0 g / L. The alkalinity of the mixed working liquid is 2-4 mg / L (calculated as potassium carbonate).

[0099] Comparative Example 4

[0100] The ratio of the bending diameter of the oleophilic fiber to the radius of the tower body is 0.9. The rest is the same as in Example 1.

[0101] A sight glass installed in the upper section of the tower revealed a slightly uneven appearance after mixing the working liquid and hydrogenation liquid. The mixed working liquid exiting the tower had an effective anthraquinone content of 162.2 g / L. The alkalinity of the mixed working liquid was 2-4 mg / L (calculated as potassium carbonate).

[0102] Comparative Example 5

[0103] The ratio of the bending diameter of the oleophilic fiber to the radius of the tower body is 2.5. The rest is the same as in Example 1.

[0104] A sight glass installed in the upper section of the tower revealed a slightly uneven appearance after mixing the working liquid and hydrogenation liquid. The mixed working liquid exiting the tower had an effective anthraquinone content of 162.1 g / L. The alkalinity of the mixed working liquid was 2-4 mg / L (calculated as potassium carbonate).

[0105] As can be seen from the operating data of the above embodiments and comparative examples, the use of a mixed solution of hydrogenating solution and working solution for alkali treatment regeneration improves the regeneration effect. In the embodiment, the upper section of the tower body is filled with oleophilic 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. The oleophilic fibers in the upper section of the tower body promote uniform mixing of the hydrogenating solution and the working solution, and slow down the impact of the mixed working solution on the alkali solution, which is beneficial for the non-diffusive contact between the mixed working solution and the alkali solution, is beneficial for the regeneration of degradation products, and is also beneficial for the rapid separation of the working solution and the alkali solution; the hydrophobic fibers in the lower section of the tower body are beneficial for the separation of the mixed working solution and the alkali solution, and the alkalinity of the mixed working solution is relatively low. The bending radius of the oleophilic fibers in the upper section of the tower body is within an appropriate range, which promotes the uniform mixing of the hydrogenating solution and the working solution.

[0106] When using a static mixer, since the upper part of the tower body is not filled with oleophilic fibers, the mixing of the hydrogenated liquid and the working liquid is poor, and the regeneration effect of the degradation products is general; the mixed working liquid has a strong impact on the alkaline solution, resulting in the alkalinity of the mixed working liquid discharged from the bottom of the tower easily exceeding the standard (indicator ≤4mg / L, calculated as potassium carbonate), and the fluctuation is large.

Claims

1. A fiber membrane regeneration tower for producing hydrogen peroxide using an anthraquinone process, characterized in that: The tower body (101) comprises a tower body (101) and a tower kettle (102), wherein the tower body (101) is vertical and 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 deep into the tower kettle (102); The tower body (101) comprises, from top to bottom, an upper tower section (1011), a middle tower section (1012), and a lower tower section (1013); the upper tower section (1011) is filled with oleophilic fiber filaments, the middle tower section (1012) is filled with hydrophilic fiber filaments, and the lower tower section (1013) is filled with hydrophobic fiber filaments; The upper portion of the tower body upper section (1011) is provided with a working liquid inlet (01) and a hydrogenation liquid inlet (02), and the top of the tower body middle section (1012) is provided with an alkali liquid inlet (03); The bottom of the tower kettle (102) is provided with an alkali liquid outlet (05), and the top is provided with an oil phase outlet (04); The length of the upper tower section (1011) is 10% to 30% of the total length of the tower body, the length of the middle tower section (1012) is 60% to 85% of the total length of the tower body, and the length of the lower tower section (1013) is 5% to 10% of the total length of the tower body; The oleophilic fiber filaments are randomly and evenly interwoven in the upper part of the tower body, and the ratio of the bending diameter of the oleophilic fiber filaments to the radius of the tower body is 1-2; The volume flow ratio of the working fluid to the hydrogenated fluid is 10 to 1; The working liquid and the hydrogenated liquid are fully mixed under the action of the oleophilic fiber filaments in the upper section (1011) of the tower body to form a mixed working liquid, and the volume flow ratio of the mixed working liquid to the alkali solution is 2000~20.

2. The fiber membrane regeneration tower according to claim 1, characterized in that: The oleophilic fiber yarns, hydrophilic fiber yarns and hydrophobic fiber yarns are all curved.

3. The fiber membrane regeneration tower according to claim 1, characterized in that: The oleophilic fiber material is one of polyvinylidene fluoride, polystyrene, and stainless steel modified by silane coupling agent; the hydrophilic fiber material is one of stainless steel treated by electrochemical oxidation, stainless steel modified by acrylic acid grafting, and stainless steel modified by polyvinyl alcohol; the hydrophobic fiber material is one of polytetrafluoroethylene, stainless steel modified by siloxane chemical vapor deposition, and stainless steel modified by electrochemical etching.

4. The fiber membrane regeneration tower according to claim 1, characterized in that: The alkali solution is an aqueous solution of one or more substances selected from the group consisting of sodium hydroxide, potassium carbonate, potassium hydroxide, and sodium carbonate.

5. The fiber membrane regeneration tower according to claim 1, characterized in that: The distance between the bottom of the tower body and the bottom of the tower kettle is 1 / 5 to 4 / 5 of the diameter of the tower kettle.

6. The fiber membrane regeneration tower according to claim 1, characterized in that: A vertical baffle (103) is provided at the bottom of the tower kettle, and a hole is provided at the bottom of the vertical baffle (103).

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