Complete equipment for preparing butanedioic anhydride by using maleic anhydride as raw material through hydrogenation

Abstract

The utility model relates to the field of production of fine chemicals, in particular to complete equipment for preparing butanedioic anhydride by using maleic anhydride as a raw material through hydrogenation. The utility model relates to complete equipment for preparing succinic anhydride through hydrogenation by using maleic anhydride as a raw material. The complete equipment comprises at least two tubular hydrogenation reactors, a fixed bed hydrogenation reactor, a gas-liquid separator and a mixer, an outlet of the mixer, inlets and outlets of the at least two tubular hydrogenation reactors, an inlet and an outlet of the fixed bed hydrogenation reactor, an inlet and a gas phase outlet of the gas-liquid separator and a hydrogen inlet of the mixer are sequentially connected in series through pipelines. The device has the advantages that the structural design is simple and reasonable, maleic anhydride conversion can be realized in a grading manner, the total conversion rate is increased, the selectivity of a target product succinic anhydride is relatively high, hydrogen can be recycled through a separated medium, and the material consumption and the energy consumption of the device are reduced.

Description

Technical Field

[0001] The utility model relates to the field of fine chemical production, in particular to a complete set of equipment for preparing succinic anhydride by hydrogenating maleic anhydride as a raw material. Background Art

[0002] As my country's requirements for environmental protection become higher and higher, environmentally friendly high-end fine chemical products and new chemical materials have become the priority development direction of the chemical industry, and degradable plastic PBS is gradually gaining favor and recognition in the market. The basic raw materials of degradable plastic PBS are succinic anhydride and 1,4-butanediol. Therefore, it is of great significance to develop the production of degradable and environmentally friendly materials by hydrogenating maleic anhydride to produce succinic anhydride.

[0003] At present, the reaction device for hydrogenating maleic anhydride to produce succinic anhydride, Chinese patent CN116020355A adopts a tubular reactor, maleic anhydride raw material enters the reactor from the bottom of the reactor, supplementary hydrogen is mixed with maleic anhydride raw material in the reactor, and a cooling medium storage tank is provided to provide cooling medium to the reactor shell side. The use of a single tubular reactor can reduce the reaction heat, but when the device is large in scale, even by increasing the number of tubular roots and increasing the length of the tubular, the effect of reducing the reaction heat is limited.

[0004] Chinese patent CN116693475A discloses a method for preparing succinic anhydride by liquid phase selective hydrogenation of maleic anhydride, wherein two fixed bed reactors are set up, and the temperature of each bed in the reactor is controlled by injecting cooling circulating liquid and cold hydrogen. On the one hand, this method has limited effect in reducing the heat of reaction; on the other hand, due to the injection of cold hydrogen, the reaction device is too large, and the material and energy consumption are increased.

[0005] Since the production of succinic anhydride by liquid-phase hydrogenation of maleic anhydride is a highly exothermic reaction, the removal of reaction heat is the key to the large-scale scale of the device. If the reaction heat is not removed in time, it will lead to an increase in reaction by-products and a decrease in the yield of the target product succinic anhydride. Therefore, how to remove the reaction heat in time and develop a complete set of equipment for the production of succinic anhydride by liquid-phase hydrogenation of maleic anhydride with a maleic anhydride conversion rate of 100% and a succinic anhydride yield of ≥96% is the key; in addition, the reaction products of maleic anhydride hydrogenation to produce succinic anhydride are three phases: gas, liquid, and water. Therefore, how to study the ability to separate the droplets entrained in the gas and return the gas to the maleic anhydride liquid-phase hydrogenation reactor is also the key to reducing the material and energy consumption of the device and reducing operating costs.

[0006] Based on this, it is necessary to develop a new set of equipment for hydrogenating maleic anhydride to produce succinic anhydride. Utility Model Content

[0007] The technical problem to be solved by the utility model is to provide a complete set of equipment for preparing succinic anhydride by hydrogenation with maleic anhydride as raw material, which effectively overcomes the defects of the prior art.

[0008] The technical solution of the utility model to solve the above technical problems is as follows:

[0009] A complete set of equipment for preparing succinic anhydride by hydrogenation with maleic anhydride as raw material comprises at least two tubular hydrogenation reactors, a fixed bed hydrogenation reactor, a gas-liquid separator and a mixer. The mixer has a maleic anhydride liquid inlet and a hydrogen inlet. The outlet of the mixer, the inlets and outlets of at least two tubular hydrogenation reactors, the inlet and outlet of the fixed bed hydrogenation reactor, the inlet and gas phase outlet of the gas-liquid separator, and the hydrogen inlet of the mixer are connected in series in sequence through pipelines.

[0010] On the basis of the above technical solution, the present invention can also be improved as follows.

[0011] Furthermore, the inlet of the above-mentioned shell-and-tube hydrogenation reactor is arranged at the top, and the outlet is arranged at the bottom. The internal inlet of the above-mentioned shell-and-tube hydrogenation reactor is connected to a spray distributor for spraying the mixed medium downward.

[0012] Furthermore, reactor interstage coolers are respectively provided on the pipeline connecting two adjacent shell-and-tube hydrogenation reactors and the pipeline connecting the shell-and-tube hydrogenation reactor and the fixed bed hydrogenation reactor.

[0013] Furthermore, two of the above-mentioned shell-and-tube hydrogenation reactors are provided.

[0014] Furthermore, each of the above-mentioned tubular hydrogenation reactors is provided with 100-500 reaction tubes.

[0015] Furthermore, an observation window is provided on the shell of the above-mentioned shell-and-tube hydrogenation reactor.

[0016] Furthermore, a flow valve is provided on the pipeline between the gas phase outlet of the gas-liquid separator and the hydrogen inlet of the mixer.

[0017] Furthermore, a gas booster is provided on the pipeline between the gas phase outlet of the gas-liquid separator and the inlet of the mixer.

[0018] Furthermore, each of the above-mentioned shell-and-tube hydrogenation reactors is provided with a temperature measuring device for monitoring the reaction temperature.

[0019] The beneficial effects of the utility model are: the structural design is simple and reasonable, maleic anhydride conversion can be achieved in stages, the overall conversion rate can be improved, the target product succinic anhydride has high selectivity, and the hydrogen can be recycled through the separated medium, thereby reducing the material consumption and energy consumption of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of an embodiment of a complete set of equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as a raw material according to the utility model;

[0021] Figure 2 This is a structural schematic diagram of another embodiment of a complete set of equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as a raw material according to the utility model;

[0022] Figure 3 This is a structural schematic diagram of another embodiment of the complete set of equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material according to the utility model.

[0023] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0024] 1. Shell and tube hydrogenation reactor; 2. Fixed bed hydrogenation reactor; 3. Gas-liquid separator; 4. Mixer; 5. Jet distributor; 6. Gas booster; 7. Reactor interstage cooler; 11. Temperature measuring device; 12. Observation window. DETAILED DESCRIPTION

[0025] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0026] Example 1

[0027] like Figure 1 As shown, the complete equipment for preparing succinic anhydride by hydrogenating maleic anhydride as a raw material in this embodiment comprises at least two tubular hydrogenation reactors 1, a fixed bed hydrogenation reactor 2, a gas-liquid separator 3 and a mixer 4. The mixer 4 has a maleic anhydride liquid inlet and a hydrogen inlet. The outlet of the mixer 4, the inlets and outlets of at least two tubular hydrogenation reactors 1, the inlet and outlet of the fixed bed hydrogenation reactor 2, the inlet and gas phase outlet of the gas-liquid separator 3, and the hydrogen inlet of the mixer 4 are connected in series in sequence through pipelines.

[0028] More specifically, in this embodiment, the outlets and inlets of two adjacent tubular hydrogenation reactors 1 are connected in series via pipelines.

[0029] The complete set of equipment for preparing succinic anhydride by hydrogenation with maleic anhydride as raw material in this embodiment adopts at least two tubular hydrogenation reactors 1 + one fixed bed hydrogenation reactor 2, and the reactor adopts the upper inlet and lower outlet mode, and the maleic anhydride raw material and hydrogen are fully mixed and uniformly in the mixer 4 and then enter the tubular hydrogenation reactor 1 and the fixed bed hydrogenation reactor 2 in sequence, wherein, in the stage of reaction of all tubular hydrogenation reactors 1, the total conversion rate of maleic anhydride in the reactor reaches 80% or more, and in the reaction stage of the fixed bed hydrogenation reactor 2, the total conversion rate of maleic anhydride reaches 100%, and the selectivity of the target product succinic anhydride is as high as 96%, and the whole equipment effectively solves the problems of large heat release, difficult removal of reaction heat, and difficulty in large-scale device scale of maleic anhydride liquid phase hydrogenation to prepare succinic anhydride. In addition, hydrogen can be effectively separated by the gas-liquid separator 3, and the hydrogen can be put into the mixer 4 through the pipeline as a raw material medium for continuous recycling, which reduces the material consumption and energy consumption of the device.

[0030] In this embodiment, the shell-and-tube hydrogenation reactor 1 and the fixed-bed hydrogenation reactor 2 are both products of the prior art. The models are adapted as needed during actual use, and are not described in detail here.

[0031] Example 2

[0032] like Figure 2 As shown, based on Example 1, the inlet of the above-mentioned shell-and-tube hydrogenation reactor 1 is arranged at the top, and the outlet is arranged at the bottom. The internal inlets of the above-mentioned shell-and-tube hydrogenation reactor 1 are all connected to the injection distributor 5 for spraying the mixed medium downward.

[0033] In this embodiment, a jet distributor 5 is connected to the inlet of the shell-and-tube hydrogenation reactor 1. During operation, the mixed liquid is sprayed evenly above the shell-and-tube through the jet distributor 5 in the form of mist, ensuring that the reactant flow is evenly mixed, the distribution effect is good, and the pressure drop is small.

[0034] Among them, the jet distributor 5 belongs to the product of the prior art. In actual use, it is sufficient to flexibly and reasonably configure an adapted model according to needs, and no further details will be given here.

[0035] Example 3

[0036] like Figure 3 As shown, based on Example 1 and / or Example 2, the pipeline connecting the two adjacent shell-and-tube hydrogenation reactors 1 and the pipeline connecting the shell-and-tube hydrogenation reactor 1 and the fixed bed hydrogenation reactor 2 are respectively provided with reactor interstage coolers 7.

[0037] In this embodiment, a reactor interstage cooler 7 is provided between each reactor, and the reactor interstage cooler 7 is used to control the inlet temperature of the subsequent reactor.

[0038] In this embodiment, the reactor interstage cooler 7 can be a conventional cooler on the pipeline, such as a tubular cooler, etc. In actual use, the adaptable model is flexibly and reasonably selected according to the needs, and no further details are given here.

[0039] Based on the above embodiment, the following optimization can be performed:

[0040] As a preferred embodiment, two of the above-mentioned shell-and-tube hydrogenation reactors 1 are provided.

[0041] In the above embodiment, the total conversion rate of maleic anhydride in the first shell-and-tube hydrogenation reactor 1 is 40-60%, the total conversion rate of maleic anhydride in the second shell-and-tube hydrogenation reactor 1 is 60-80%, and the total conversion rate of maleic anhydride in the fixed-bed hydrogenation reactor 2 is 100%. The conversion efficiency is relatively high, and the selectivity of the target product succinic anhydride is as high as 96%.

[0042] In this embodiment, each of the above-mentioned tubular hydrogenation reactors 1 is provided with 100-500 reaction tubes.

[0043] As a preferred embodiment, an observation window 12 is provided on the shell of the shell-and-tube hydrogenation reactor 1 .

[0044] In the above embodiment, observing the internal situation of the shell-and-tube hydrogenation reactor 1 through the observation window 12 is conducive to troubleshooting the internal faults thereof, and can timely discover the faults to ensure that the shell-and-tube hydrogenation reactor 1 operates well.

[0045] As a preferred embodiment, a flow valve is provided on the pipeline between the gas phase outlet of the gas-liquid separator 3 and the hydrogen inlet of the mixer 4 .

[0046] In the above embodiment, the amount of hydrogen entering the mixer 4 can be controlled by the flow valve to ensure that the hydrogen and maleic anhydride liquid are mixed in a good ratio.

[0047] As a preferred embodiment, a gas booster 6 is provided on the pipeline between the gas phase outlet of the gas-liquid separator 3 and the inlet of the mixer 4 .

[0048] In the above embodiment, the gas booster 6 can ensure good transportation of hydrogen on the pipeline on the one hand, and on the other hand, the hydrogen entering the mixer 4 can be pressurized to facilitate mixing, thereby realizing the recycling of hydrogen and reducing material and energy consumption.

[0049] As a preferred embodiment, each of the above-mentioned shell-and-tube hydrogenation reactors 1 is provided with a temperature measuring device 11 for monitoring the reaction temperature.

[0050] In the above embodiment, since a cooling medium for heat exchange with the shell and tube hydrogenation reactor 1 is introduced into the shell and tube hydrogenation reactor 1, the shell and tube hydrogenation reactor 1 has a cooling medium inlet and outlet connected to an external coolant circulation pipeline. Therefore, by providing a temperature measuring device 11, the shell and tube reaction temperature can be monitored in real time, and the flow rate of the cooling medium entering the shell and tube hydrogenation reactor 1 for heat exchange is adjusted according to the temperature information, thereby achieving the purpose of controlling the reaction temperature by controlling the amount of cooling medium.

[0051] The temperature detector 11 may be a temperature sensor or other suitable temperature measuring components.

[0052] In this embodiment, a collector can be set at the outlet of the shell-and-tube hydrogenation reactor 1 and the fixed bed hydrogenation reactor 2 to prevent leakage of the catalyst and the ceramic ball filler, while ensuring that the reaction effluent flows out evenly and slowing down the occurrence of bias flow. The pressure of the entire reaction process is 0-3.0 MPa, the molar ratio of hydrogen anhydride is 1-10, and the reaction temperature is 0-150°C.

[0053] In this embodiment, the gas-liquid separator 3 adopts a product with micro-cyclone in the prior art. The product from the outlet of the fixed bed hydrogenation reactor 2 enters the gas-liquid separator 3 for three-phase separation of gas, oil and water. In the gas-liquid separator 3, the tangential velocity is dominant, which drives the particles to perform high-speed rotational motion, and they are thrown to the wall of the device under the effect of centrifugal force and separated.

[0054] In this embodiment, the mixer 4 can be a gas-liquid mixer currently available on the market. In actual use, the appropriate model can be flexibly and reasonably selected according to needs, which will not be elaborated here.

[0055] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0056] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0057] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0058] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0059] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. 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 representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0060] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A complete set of equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material, characterized in that: The invention comprises at least two tubular hydrogenation reactors (1), a fixed bed hydrogenation reactor (2), a gas-liquid separator (3) and a mixer (4); the mixer (4) has a maleic anhydride liquid inlet and a hydrogen inlet; the outlet of the mixer (4), the inlets and outlets of at least two tubular hydrogenation reactors (1), the inlet and outlet of the fixed bed hydrogenation reactor (2), the inlet and gas phase outlet of the gas-liquid separator (3), and the hydrogen inlet of the mixer (4) are connected in series in sequence through pipelines.

2. The complete set of equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material according to claim 1, characterized in that: The inlet of the shell-and-tube hydrogenation reactor (1) is arranged at the top, and the outlet is arranged at the bottom. The internal inlets of the shell-and-tube hydrogenation reactor (1) are all connected to a spray distributor (5) for spraying the mixed medium downward.

3. A complete set of equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material according to claim 1 or 2, characterized in that: Reactor interstage coolers (7) are respectively provided on the pipeline connecting two adjacent shell-and-tube hydrogenation reactors (1) and the pipeline connecting the shell-and-tube hydrogenation reactor (1) and the fixed bed hydrogenation reactor (2).

4. The complete set of equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material according to claim 1, characterized in that: The shell-and-tube hydrogenation reactors (1) are provided with two.

5. The complete set of equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material according to claim 1, characterized in that: Each of the tubular hydrogenation reactors (1) is provided with 100 to 500 reaction tubes.

6. The complete equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material according to claim 1, characterized in that: An observation window (12) is provided on the outer shell of the shell-and-tube hydrogenation reactor (1).

7. The complete equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material according to claim 1, characterized in that: A flow valve is provided on the pipeline between the gas phase outlet of the gas-liquid separator (3) and the hydrogen inlet of the mixer (4).

8. The complete equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material according to claim 1, characterized in that: A gas booster (6) is provided on the pipeline between the gas phase outlet of the gas-liquid separator (3) and the inlet of the mixer (4).

9. The complete equipment for preparing succinic anhydride by hydrogenation using maleic anhydride as raw material according to claim 1, characterized in that: Each of the shell-and-tube hydrogenation reactors (1) is provided with a temperature measuring device (11) for monitoring the reaction temperature.

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