Tail gas recycling system for preparing glyoxylic acid by ozonation maleic anhydride method

Abstract

The utility model discloses a tail gas recycling system for preparing glyoxylic acid by an ozonation maleic anhydride method, which comprises a washing tower, a tail gas inlet is arranged close to the bottom of the washing tower, and a first gas outlet is arranged at the top of the washing tower; the front buffer tank is provided with a second gas inlet and a second gas outlet, and the second gas inlet is connected with the first gas outlet; the supercharging device is connected with the second gas outlet; the adsorption tower is provided with a third gas inlet and a third gas outlet, the third gas inlet is connected with the supercharging device, the third gas inlet is arranged close to the bottom of the adsorption tower, the third gas outlet is arranged close to the top of the adsorption tower, and impurity adsorption filler is arranged in the adsorption tower; and the rear buffer tank is provided with a fourth gas inlet and a fourth gas outlet, and the fourth gas inlet is connected with the third gas outlet. According to the utility model, oxygen in tail gas is recycled, and energy conservation and consumption reduction are realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of tail gas treatment, and particularly relates to a tail gas recycling system for preparing glyoxylic acid by an ozone oxidation maleic anhydride process. Background Art

[0002] When ozone oxidation of maleic anhydride is used to produce glyoxylic acid, it relies on ozone and a solid acid catalyst to promote the conversion of maleic anhydride into the desired glyoxylic acid. Ozone is produced by oxidizing ≥90% of oxygen. The tail gas after the ozone oxidation process contains approximately 80%-82% oxygen, 10% carbon dioxide, 5%-7% argon, 3%-5% nitrogen, saturated water, about 0.1% ozone, and VOCs (volatile organic compounds, small molecules, basic carbon 7 or less).

[0003] At present, the waste gas after the ozone oxidation process is directly discharged after being treated to meet the standards, but the waste gas still contains more than 80% oxygen, which greatly wastes resources and costs.

[0004] In view of this, how to design a technology that can recycle oxygen in exhaust gas is a technical problem to be solved by the present utility model. Utility Model Content

[0005] The utility model aims to provide a tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride, so as to realize the recycling of oxygen in the tail gas and save energy and reduce consumption.

[0006] In order to achieve the above technical objectives, the utility model adopts the following technical solutions:

[0007] A tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride, comprising:

[0008] a scrubber having an exhaust gas inlet disposed near the bottom and a first gas outlet disposed at the top, the scrubber being configured to absorb volatile organic acids in the exhaust gas;

[0009] a front buffer tank, on which a second gas inlet and a second gas outlet are provided, the second gas inlet is connected to the first gas outlet, and the front buffer tank is configured to stabilize the pressure of the gas after being scrubbed by the scrubbing tower;

[0010] a pressurizing device connected to the second gas outlet, the pressurizing device being configured to pressurize the gas discharged from the second gas outlet;

[0011] An adsorption tower, on which a third gas inlet and a third gas outlet are provided, wherein the third gas inlet is connected to the booster device, the third gas inlet is arranged near the bottom of the adsorption tower, and the third gas outlet is arranged near the top of the adsorption tower, and an impurity adsorption filler is arranged inside the adsorption tower;

[0012] A rear buffer tank is provided with a fourth gas inlet and a fourth gas outlet, wherein the fourth gas inlet is connected to the third gas outlet, and the rear buffer tank is configured to stabilize the pressure of the gas after the impurities are adsorbed by the adsorption tower.

[0013] In some embodiments of the present application, an alkaline solution spraying mechanism is provided in the washing tower.

[0014] In some embodiments of the present application, the alkali solution spraying mechanism includes a multi-layer spray head arranged from top to bottom in the washing tower.

[0015] In some embodiments of the present application, the impurity adsorption filler includes a volatile organic compound adsorption filler, a moisture adsorption filler, a carbon dioxide adsorption filler and an argon adsorption filler.

[0016] In some embodiments of the present application, the adsorption towers include multiple groups that can work in rotation, and the adsorption towers are connected by electrically controlled valves and pipelines.

[0017] In some embodiments of the present application, the adsorption tower is equipped with a vacuum pump, and the vacuum pump is configured to assist in desorption and regeneration of the impurity adsorption filler.

[0018] In some embodiments of the present application, the tail gas recycling system for producing glyoxylic acid by the ozone oxidation of maleic anhydride method also includes a pressure equalizing tank, which is provided with a fifth gas inlet and a fifth gas outlet respectively connected to the multiple groups of adsorption towers, and the pressure equalizing tank is configured to respectively equalize the pressures in the multiple groups of adsorption towers.

[0019] In some embodiments of the present application, the pressurizing device includes an oxygen compressor.

[0020] In some embodiments of the present application, the pressure of the gas discharged from the second gas outlet compressed by the oxygen compressor is 0.15Mkpa~0.2Mkpa.

[0021] Compared with the prior art, the advantages and positive effects of the utility model are: by setting up a washing tower to absorb the acidic gas in the tail gas first, and then the tail gas that has absorbed the acidic gas is pressurized and purified by a supercharging device, and then the tail gas enters the adsorption tower, and the various impurity adsorption fillers in the adsorption tower adsorb the remaining impurities in the tail gas to obtain oxygen with a content greater than 90%, which can be sent to the ozone preparation system for continued use; in addition, the front buffer tank and the rear buffer tank are set during the treatment process, which can effectively stabilize the pressure during the tail gas treatment process and improve the safety of the tail gas treatment process. The utility model can treat the tail gas after the ozone oxidation process and put it into the ozone oxidation process again, reducing the waste of resources, and the entire treatment process saves energy and reduces consumption, adding economic value to the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 A schematic diagram of an embodiment of the tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride according to the utility model;

[0024] Figure 2 The utility model is a schematic diagram of the structure of the washing tower in the embodiment of the tail gas recycling system for preparing glyoxylic acid by the ozone oxidation of maleic anhydride.

[0025] Description of reference numerals:

[0026] 100, washing tower; 101, tail gas inlet; 102, first gas outlet; 103, spray head;

[0027] 200, front buffer tank; 201, second gas inlet; 202, second gas outlet;

[0028] 300. Pressure boosting device;

[0029] 400, adsorption tower; 401, third gas inlet; 402, third gas outlet;

[0030] 500, rear buffer tank; 501, fourth gas inlet; 502, fourth gas outlet;

[0031] 600, pressure equalizing tank; 601, fifth gas inlet; 602, fifth gas outlet;

[0032] 700. Vacuum pump. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] It should be noted that in the description of the present invention, the terms "upper", "lower", "inner", etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", "third", "fourth", and "fifth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0035] In the present invention, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The disclosure below provides many different embodiments or examples for realizing different structures of the utility model. In order to simplify the disclosure of the utility model, the components and settings of specific examples are described below. Of course, they are merely examples, and the purpose is not to limit the utility model. In addition, the utility model may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the utility model provides various specific examples of processes and materials, but those of ordinary skill in the art may be aware of the application of other processes and / or the use of other materials.

[0037] like Figure 1 to Figure 2 As shown, this embodiment provides a tail gas recycling system for preparing glyoxylic acid by the ozone oxidation of maleic anhydride method. In the process of preparing glyoxylic acid by the ozone oxidation of maleic anhydride method, the tail gas after ozone is prepared by the ozone oxidation process can be treated, and the oxygen in the tail gas can be recovered and applied to the ozone oxidation process again to prepare ozone, thereby reducing the waste of resources and achieving the purpose of energy saving and consumption reduction.

[0038] The tail gas recycling system for preparing glyoxylic acid by the ozone oxidation of maleic anhydride method comprises a washing tower 100, a front buffer tank 200, a pressurizing device, an adsorption tower 400 and a rear buffer tank 500.

[0039] A tail gas inlet 101 is provided near the bottom of the washing tower 100, and a first gas outlet 102 is provided at the top of the washing tower 100. The washing tower 100 is used to absorb volatile organic acids in the tail gas entering the washing tower 100; the tail gas enters the washing tower 100 from a position near the bottom of the washing tower 100 and is then discharged from the top of the washing tower 100, which can increase the washing time of the tail gas and facilitate the full adsorption of the volatile organic acids in the tail gas.

[0040] The front buffer tank 200 is provided with a second gas inlet 201 and a second gas outlet 202, and the second gas inlet 201 is connected to the first gas outlet 102 of the scrubber 100. The front buffer tank 200 is used to stabilize the pressure of the gas coming out of the scrubber 100. Since the tail gas discharged by the ozone oxidation process may have unstable pressure, and this situation continues after entering the scrubber 100, the front buffer tank 200 is provided to stabilize the pressure of the gas, so as to facilitate a safer continuation of the gas treatment process.

[0041] The booster 300 is connected to the second gas outlet 202 of the front buffer tank 200, and is used to boost the pressure of the gas discharged from the second gas outlet 202. Since the gas needs to be at a high pressure when the impurities in the gas are subsequently adsorbed in the adsorption tower 400, the booster 300 is provided to compress and boost the pressure of the gas discharged from the second gas outlet 202.

[0042] The adsorption tower 400 is provided with a third gas inlet 401 and a third gas outlet 402. The third gas inlet 401 is arranged near the bottom of the adsorption tower 400, and the third gas outlet 402 is arranged near the top of the adsorption tower 400. An impurity adsorption filler is arranged in the adsorption tower 400. The compressed and pressurized gas enters the adsorption tower 400, and the impurity adsorption filler absorbs impurities in the gas. The third gas inlet 401 is arranged near the bottom of the adsorption tower 400 to increase the contact area between the incoming gas and the impurity adsorption filler, thereby improving the impurity adsorption efficiency and the effect of impurity adsorption.

[0043] The rear buffer tank 500 is provided with a fourth gas inlet 501 and a fourth gas outlet 502, and the fourth gas inlet 501 is connected to the third gas outlet 402. The rear buffer tank 500 is used to stabilize the pressure of the gas coming out of the adsorption tower 400. Since the gas is pressurized by the booster 300 and then adsorbed in the adsorption tower 400, there may be unstable pressure. Therefore, the rear buffer tank 500 is provided to stabilize the pressure of the gas, so as to facilitate safer re-introduction into the ozone oxidation process for use.

[0044] When in use, the tail gas discharged from the ozone oxidation process first enters the scrubbing tower 100 through the pipeline and the tail gas inlet 101, and the scrubbing tower 100 adsorbs the volatile organic acids therein; the gas without the volatile organic acids is discharged from the first gas outlet 102, and then enters the front buffer tank 200 through the pipeline and the second gas inlet 201 to stabilize the pressure, and then is discharged from the second gas outlet 202; the gas discharged from the second gas outlet 202 enters the boosting device 300 for compression and boosting, which is convenient for subsequent adsorption and extraction; then the boosted gas is passed through the pipeline and the third gas inlet The gas enters the adsorption tower 400 through the third gas outlet 401. The impurity adsorption filler in the adsorption tower 400 adsorbs the remaining impurities in the gas. The gas after adsorbing the impurities is discharged from the third gas outlet 402. At this time, the oxygen content of the gas discharged from the third gas outlet 402 is greater than 90%, which is a qualified raw material for the preparation of the ozone oxidation process. Finally, the gas enters the rear buffer tank 500 through the pipeline and the fourth gas inlet 501 to stabilize the pressure, and is finally discharged from the fourth gas outlet 502. The fourth gas outlet 502 is connected to the oxygen supply end of the ozone oxidation process, thereby realizing the recycling of the tail gas of the ozone oxidation process.

[0045] like Figure 2 As shown, an alkali solution spraying mechanism is provided in the washing tower 100, and the alkali solution spraying mechanism includes a multi-layer spray head 103 arranged from top to bottom in the washing tower 100, and in this embodiment, a double-layer spray head 103. Alkali solution is sprayed from the double-layer spray head 103 to neutralize the volatile organic acid in the tail gas entering the washing tower 100, thereby removing the volatile organic acid in the tail gas. The double-layer spray head 103 increases the contact area between the tail gas and the alkali solution, and improves the washing efficiency.

[0046] The impurity adsorption fillers include volatile organic matter adsorption fillers, moisture adsorption fillers, carbon dioxide adsorption fillers, and argon adsorption fillers. Various impurity adsorption fillers are arranged in the adsorption tower 400. After the gas enters the adsorption tower 400, the various impurity adsorption fillers respectively adsorb the impurities in the gas to complete the purification of the gas.

[0047] like Figure 1As shown, the adsorption tower 400 includes multiple groups that can work in rotation, and in this embodiment, four groups are included. The four groups of adsorption towers 400 are connected in parallel through electric control valves and pipelines. Since the adsorption capacity of the impurity adsorption filler is limited and needs to be desorbed and regenerated regularly, the provision of multiple groups of adsorption towers 400 that can work in rotation can ensure the continuous operation of the tail gas recycling system and improve production efficiency; the electric control valve can control the four groups of adsorption towers 400 to work in rotation according to the set program, and the program used is the existing program on the market. The utility model does not involve the improvement of the program, so it will not be repeated here.

[0048] The adsorption tower 400 is equipped with a vacuum pump 700, which is connected to the inside of the four groups of adsorption towers 400 respectively, and is used to assist the desorption and regeneration of the impurity adsorption filler. When in use, when the impurity adsorption capacity of the impurity adsorption filler in a certain group of adsorption towers 400 reaches a threshold value, the electric control valve of this adsorption tower 400 is closed, and the gas pressurized by the booster device 300 enters the next group of adsorption towers 400 for adsorption. At the same time, the vacuum pump 700 starts to work, reducing the pressure in the adsorption tower 400 of the group whose impurity adsorption capacity of the impurity adsorption filler reaches the threshold value, so that the impurities are desorbed from the impurity adsorption filler, thereby completing the desorption and regeneration of the impurity adsorption filler; the desorbed impurities can be removed regularly.

[0049] like Figure 1 As shown, the tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride also includes a pressure equalizing tank 600, on which a fifth gas inlet 601 and a fifth gas outlet 602 respectively connected to multiple groups of adsorption towers 400 are provided, and the pressure equalizing tank 600 is used to respectively balance the pressures in the multiple groups of adsorption towers 400.

[0050] When a group of adsorption towers 400 has finished adsorbing the pressurized gas, that is, the impurity adsorption capacity of the impurity adsorption filler has reached a threshold, the incompletely purified gas enters the pressure equalizing tank 600. Since the incompletely purified gas will cause unstable gas pressure when it accumulates to a certain concentration in the adsorption tower 400, before entering the next group of adsorption towers 400, the incompletely purified gas first enters the pressure equalizing tank 600 to stabilize the gas pressure, and then enters the next group of adsorption towers 400 for treatment.

[0051] The booster device 300 includes an oxygen compressor, which compresses the gas discharged from the second gas outlet 202 to a pressure of 0.15Mkpa-0.2Mkpa. The oxygen compressor has a simple structure and is easy to operate. 0.15Mkpa-0.2Mkpa is the optimal pressure range for the gas to enter the adsorption tower 400 for impurity adsorption.

[0052] The tail gas recycling system for preparing glyoxylic acid by the ozone oxidation maleic anhydride method provided by the utility model can treat the tail gas and supply it as raw material again, which greatly reduces the waste of resources and brings huge economic benefits to the enterprise. In the description of this specification, the description of reference terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0053] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the above embodiments, or to replace some of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions claimed to be protected by the present invention.

Claims

1. A tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride, characterized in that: include: a scrubber having an exhaust gas inlet disposed near the bottom and a first gas outlet disposed at the top, the scrubber being configured to absorb volatile organic acids in the exhaust gas; a front buffer tank, on which a second gas inlet and a second gas outlet are provided, the second gas inlet is connected to the first gas outlet, and the front buffer tank is configured to stabilize the pressure of the gas after being scrubbed by the scrubbing tower; a pressurizing device connected to the second gas outlet, the pressurizing device being configured to pressurize the gas discharged from the second gas outlet; An adsorption tower, on which a third gas inlet and a third gas outlet are provided, wherein the third gas inlet is connected to the booster device, the third gas inlet is arranged near the bottom of the adsorption tower, and the third gas outlet is arranged near the top of the adsorption tower, and an impurity adsorption filler is arranged inside the adsorption tower; A rear buffer tank is provided with a fourth gas inlet and a fourth gas outlet, wherein the fourth gas inlet is connected to the third gas outlet, and the rear buffer tank is configured to stabilize the pressure of the gas after the impurities are adsorbed by the adsorption tower.

2. The tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride according to claim 1, characterized in that: An alkali solution spraying mechanism is arranged in the washing tower.

3. The tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride according to claim 2, characterized in that: The alkali solution spraying mechanism comprises a plurality of layers of spraying heads which are arranged from top to bottom in the washing tower.

4. The tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride according to claim 1, characterized in that: The impurity adsorption filler includes a volatile organic matter adsorption filler, a moisture adsorption filler, a carbon dioxide adsorption filler and an argon adsorption filler.

5. The tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride according to claim 1, characterized in that: The adsorption towers include a plurality of groups that can work in rotation, and the adsorption towers are connected by electronically controlled valves and pipelines.

6. The tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride according to claim 5, characterized in that: The adsorption tower is equipped with a vacuum pump, and the vacuum pump is configured to assist the desorption and regeneration of the impurity adsorption filler.

7. The tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride according to claim 6, characterized in that: The tail gas recycling system for producing glyoxylic acid by the ozone oxidation of maleic anhydride method also includes a pressure equalizing tank, which is provided with a fifth gas inlet and a fifth gas outlet respectively connected to the multiple groups of adsorption towers, and the pressure equalizing tank is configured to respectively equalize the pressure in the multiple groups of adsorption towers.

8. The tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride according to claim 1, characterized in that: The pressurizing device comprises an oxygen compressor.

9. The tail gas recycling system for preparing glyoxylic acid by ozone oxidation of maleic anhydride according to claim 8, characterized in that: The pressure of the gas discharged from the second gas outlet compressed by the oxygen compressor is 0.15Mkpa~0.2Mkpa.

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