Alkylation ethylbenzene preparation device with protection reactor

Abstract

The utility model provides an alkylation preparation ethylbenzene device with protection reactors, which comprises an alkylation reactor and a first protection reactor, a benzene feeding pipeline is arranged at the bottom of the alkylation reactor, a reaction liquid discharging pipeline is arranged at the top of the alkylation reactor, an ethylene feeding pipeline is further arranged, and the ethylene feeding pipeline is provided with a compressor; a protective reaction bed layer is arranged on the first protective reactor, a low-temperature catalyst is arranged on the protective reaction bed layer, a fresh benzene feeding pipeline and a protective reactor ethylene feeding pipeline are arranged at the bottom of the first protective reactor, a first heater is arranged on the fresh benzene feeding pipeline, and a second heater is arranged on the protective reactor ethylene feeding pipeline. An ethylene feeding pipeline of the protection reactor is provided with a first compressor, an outlet of the first protection reactor is connected to a benzene feeding pipeline, and the benzene feeding pipeline is provided with a second heater. Basic nitride and sulfur-containing compound impurities contained in the raw material benzene can be removed to protect an acid catalyst in the alkylation reactor, and the yield of ethylbenzene can be increased.

Description

Technical Field

[0001] The utility model relates to the technical field of ethylbenzene production, in particular to an alkylation ethylbenzene preparation device with a protective reactor. Background Art

[0002] Ethylbenzene, as an important chemical product, is mainly produced by the alkylation reaction of raw materials benzene and ethylene. The reaction equation is: Because the raw benzene contains basic nitrogen compounds and sulfur-containing impurities, these impurities adsorb onto the acidic sites of the catalyst, causing catalyst deactivation. Although regeneration can restore activity, regeneration is difficult and time-consuming. Therefore, a protective device, or guard reactor, is required for the acidic catalyst in the alkylation reactor. Existing guard reactors simply absorb and remove basic nitrogen compounds and sulfur-containing impurities from benzene, failing to effectively utilize the guard reactor's production capacity to increase ethylbenzene production. Summary of the Invention

[0003] In view of this, the utility model aims to provide an alkylation ethylbenzene production device with a protective reactor, which can not only absorb and remove the alkaline nitrogen compounds and sulfur-containing compound impurities contained in the raw benzene to protect the acidic catalyst in the alkylation reactor, but also increase the output of ethylbenzene.

[0004] The utility model provides an alkylation device for preparing ethylbenzene with a guard reactor, comprising an alkylation reactor and a first guard reactor. The alkylation reactor comprises an upper reaction bed and a lower reaction bed, alkylation catalysts being installed on the upper and lower reaction beds. A benzene feed pipeline is provided at the bottom of the alkylation reactor, and a reaction liquid discharge pipeline is provided at the top. An upper ethylene feed pipeline and a lower ethylene feed pipeline are provided at the bottoms of the upper and lower reaction beds, respectively. Both the upper ethylene feed pipeline and the lower ethylene feed pipeline are provided with compressors for injecting ethylene into the alkylation reactor. The first guard reactor is provided with a guard reaction bed, a low-temperature catalyst being installed on the guard reaction bed. A fresh benzene feed pipeline and a guard reactor ethylene feed pipeline are provided at the bottom of the first guard reactor. The fresh benzene feed pipeline is provided with a fresh benzene feed pump and a first heater for heating fresh benzene. The guard reactor ethylene feed pipeline is provided with a first compressor for injecting ethylene into the guard reactor for reaction. The outlet of the first guard reactor is connected to the benzene feed pipeline, and the benzene feed pipeline is provided with a second heater.

[0005] Furthermore, a hot reaction liquid extraction pipeline is provided between the upper and lower reaction beds, and an extraction pump is provided on the hot reaction liquid extraction pipeline.

[0006] Furthermore, the alkylation ethylbenzene production unit of the guard reactor is also provided with a second guard reactor.

[0007] Furthermore, a first valve is provided before the hot reaction liquid extraction pipeline enters the first protection reactor, a second valve is provided before the fresh benzene feed pipeline enters the first protection reactor, a third valve is provided before the protection reactor ethylene feed pipeline enters the first protection reactor, and a seventh valve is provided at the outlet of the first protection reactor; a branch is provided on the hot reaction liquid extraction pipeline, and a fourth valve is provided before entering the second protection reactor, a branch is provided on the fresh benzene feed pipeline, and a fifth valve is provided before entering the second protection reactor, a branch is provided on the protection reactor ethylene feed pipeline, and a third valve is provided before entering the second protection reactor, and an eighth valve is provided at the outlet of the second protection reactor.

[0008] Furthermore, a first thermometer and a second thermometer are respectively provided at the bottom of the first protection reactor and the second protection reactor.

[0009] Furthermore, the first thermometer and the second thermometer are provided with upper and lower limits.

[0010] Furthermore, the first thermometer and the second thermometer are electrically connected to the first heater.

[0011] Furthermore, a third thermometer is provided at the bottom of the alkylation reactor, and the third thermometer is provided with an upper limit and a lower limit.

[0012] Furthermore, the third thermometer is electrically connected to the second heater. When the temperature of the third thermometer is higher than the upper limit, the heating power of the second heater is reduced. When the temperature of the third thermometer is lower than the lower limit, the heating power of the second heater is increased.

[0013] Furthermore, a fourth thermometer is provided in the middle of the alkylation reactor, and the fourth thermometer is provided with an upper limit and a lower limit. The fourth thermometer is electrically connected to the compressor of the lower ethylene feed pipeline. When the temperature of the fourth thermometer is higher than the upper limit, the ethylene outflow of the compressor of the lower ethylene feed pipeline is reduced. When the temperature of the fourth thermometer is lower than the lower limit, the ethylene outflow of the compressor of the lower ethylene feed pipeline is increased.

[0014] Beneficial effects:

[0015] The utility model provides an alkylation device for preparing ethylbenzene with a guard reactor, comprising an alkylation reactor and a first guard reactor, wherein the alkylation reactor is provided with an upper and a lower reaction bed layer, the upper and lower reaction beds are provided with an alkylation catalyst, a benzene feed pipeline is provided at the bottom of the alkylation reactor, a reaction liquid discharge pipeline is provided at the top, an upper ethylene feed pipeline and a lower ethylene feed pipeline are provided at the bottom of the upper and lower reaction beds, respectively, the upper ethylene feed pipeline and the lower ethylene feed pipeline are provided with compressors for injecting ethylene into the alkylation reactor; the first guard reactor is provided with a guard reaction bed layer, and the guard reaction bed layer is provided with a low-temperature catalyst. The bottom of the first guard reactor is provided with a fresh benzene feed pipeline and a guard reactor ethylene feed pipeline. The fresh benzene feed pipeline is provided with a fresh benzene feed pump and a first heater for heating fresh benzene. The ethylene feed pipeline of the guard reactor is provided with a first compressor for injecting ethylene into the guard reactor for reaction. The outlet of the first guard reactor is connected to the benzene feed pipeline, and the benzene feed pipeline is provided with a second heater. The low-temperature catalyst in the guard reactor can not only absorb and remove the basic nitrogen compounds and sulfur-containing compound impurities contained in the raw benzene, but also protect the acidic catalyst in the alkylation reactor and increase the output of ethylbenzene. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of an alkylation device for preparing ethylbenzene with a guard reactor in the present invention;

[0017] In the figure, the reference numerals are as follows: 100, alkylation unit for preparing ethylbenzene with guard reactor; 1, alkylation reactor; 11, upper ethylene feed line; 12, lower ethylene feed line; 13, hot reaction liquid extraction line; 131, extraction pump; 132, first valve; 133, fourth valve; 14, third thermometer; 15, fourth thermometer; 16, upper reaction bed; 17, lower reaction bed; 2, first guard reactor; 21, first thermometer; 22, first guard Reactor bed; 3. Second protective reactor; 31. Second thermometer; 32. Second protective reactor bed; 4. Fresh benzene feed line; 41. Fresh benzene feed pump; 42. First heater; 43. Second valve; 44. Fifth valve; 5. Protective reactor ethylene feed line; 51. First compressor; 52. Third valve; 53. Sixth valve; 6. Benzene feed line; 61. Seventh valve; 62. Eighth valve; 63. Second heater; 7. Reaction liquid discharge line. DETAILED DESCRIPTION

[0018] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the examples in the specification. The methods described are all conventional methods unless otherwise specified, and the raw materials described can be obtained from public commercial channels unless otherwise specified.

[0019] The term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0020] like Figure 1 As shown, this embodiment provides an alkylation device 100 for preparing ethylbenzene with a guard reactor, comprising an alkylation reactor 1 and a first guard reactor 2. The alkylation reactor 1 comprises an upper reaction bed 16 and a lower reaction bed 17, each containing an alkylation catalyst. A benzene feed line 6 is provided at the bottom of the alkylation reactor 1, and a reaction liquid discharge line 7 is provided at the top. An upper ethylene feed line 11 and a lower ethylene feed line 12 are provided at the bottoms of the upper and lower reaction beds, respectively. Both the upper ethylene feed line 11 and the lower ethylene feed line 12 are equipped with compressors for injecting ethylene into the alkylation reactor. A first guard reactor bed 22 is provided on the first guard reactor 2, and a low-temperature catalyst is provided on the first guard reactor bed. The low-temperature catalyst allows benzene to undergo an alkylation reaction with ethylene at a relatively low temperature. The bottom of the first guard reactor 2 is equipped with a fresh benzene feed line 4 and a guard reactor ethylene feed line 5. The fresh benzene feed line is equipped with a fresh benzene feed pump 41 and a first heater 42 for heating the fresh benzene. The guard reactor ethylene feed line 5 is equipped with a first compressor 51, which injects ethylene into the guard reactor for reaction. The outlet of the first guard reactor 2 is connected to a benzene feed line 6, which is equipped with a second heater 63. The benzene, after the removal of basic nitrogen compounds and sulfur-containing compound impurities, and the remaining reaction products, are fed through the benzene feed line 6 into the alkylation reactor 1 for further alkylation reaction.

[0021] Preferably, a hot reaction liquid extraction pipeline 13 is provided between the upper and lower reaction beds. The hot reaction liquid extraction pipeline 13 is provided with an extraction pump 131. The extraction pump 131 can inject part of the high-temperature reaction liquid (mainly composed of excess benzene that has not participated in the reaction and reaction products) that has passed through the lower reaction bed into the protective reactor as a heat source and reaction raw material.

[0022] Preferably, the alkylation unit for preparing ethylbenzene with a guard reactor is further provided with a second guard reactor 3. A second guard reactor bed 32 is provided on the first guard reactor 2, and a low-temperature catalyst is provided on the bed of the second guard reactor. Since the low-temperature catalyst in the guard reactor not only performs the alkylation reaction, but more importantly, adsorbs and removes alkaline nitrogen compounds and sulfur-containing compound impurities contained in benzene, the low-temperature catalyst in the guard reactor needs to be frequently activated, regenerated or replaced. When the first guard reactor 2 is stopped for activation, regeneration or replacement of the catalyst, the unit can be switched to the second guard reactor 3 for production without affecting the operation of the entire production line. Specifically, a first valve 132 is set before the hot reaction liquid extraction pipeline 13 enters the first protection reaction, a second valve 43 is set before the fresh benzene feed pipeline 4 enters the first protection reaction, a third valve 52 is set before the protection reactor ethylene feed pipeline 5 enters the first protection reaction, and a seventh valve 61 is set at the outlet of the first protection reactor; a branch is set on the hot reaction liquid extraction pipeline 13, and a fourth valve 133 is set before entering the second protection reaction, a branch is set on the fresh benzene feed pipeline 4, and a fifth valve 44 is set before entering the second protection reaction, a branch is set on the protection reactor ethylene feed pipeline 5, and a sixth valve 53 is set before entering the second protection reaction, and an eighth valve 62 is set at the outlet of the second protection reactor.

[0023] When the first protection reactor 2 is connected to the alkylation ethylbenzene production unit having a protection reactor, the first valve 132, the second valve 43, the third valve 52 and the seventh valve 61 are opened, and the fourth valve 133, the fifth valve 44, the sixth valve 53 and the eighth valve 62 are closed; when the first protection reactor 2 needs to be activated, regenerated or the catalyst is replaced, the first valve 132, the second valve 43 and the third valve 52 are closed, the fourth valve 133, the fifth valve 44 and the sixth valve 53 are opened, and the second protection reactor 3 is switched to the working state.

[0024] Preferably, a first thermometer 21 and a second thermometer 31 are respectively provided at the bottom of the first protective reactor 2 and the second protective reactor 3. The first thermometer 21 has upper and lower limits and is electrically connected to the first heater 42. When the temperature of the first thermometer 21 is higher than the upper limit, the heating power of the first heater 42 is reduced. When the temperature of the first thermometer 21 is lower than the lower limit, the heating power of the first heater 42 is increased. The second thermometer 31 has the same function as the first thermometer 21 and is not further described here.

[0025] Preferably, a third thermometer 14 is provided at the bottom of the alkylation reactor 1. The third thermometer 14 has upper and lower limits. The third thermometer 14 is electrically connected to the second heater 63. When the temperature of the third thermometer 14 is higher than the upper limit, the heating power of the second heater 63 is reduced. When the temperature of the third thermometer 14 is lower than the lower limit, the heating power of the second heater 63 is increased.

[0026] Preferably, a fourth thermometer 15 is provided in the middle of the alkylation reactor 1. The fourth thermometer 15 is provided with an upper limit and a lower limit. The fourth thermometer 15 is electrically connected to the compressor of the lower ethylene feed pipeline. When the temperature of the fourth thermometer 15 is higher than the upper limit, the ethylene outflow of the compressor of the lower ethylene feed pipeline 11 is reduced. When the temperature of the fourth thermometer 15 is lower than the lower limit, the ethylene outflow of the compressor of the lower ethylene feed pipeline 11 is increased.

[0027] The working mode of the alkylation preparation ethylbenzene device with a protective reactor of the utility model is:

[0028] Fresh benzene is heated through a first heater 42 via fresh benzene feed line 4 before entering the bottom of guard reactor 2. Ethylene is then fed through ethylene feed line 5. The molar ratio of ethylene to fresh benzene is 1:10 to 1:5. The low-temperature catalyst in the guard reactor bed of guard reactor 2 adsorbs and removes basic nitrogen compounds and sulfur-containing impurities while catalyzing the alkylation reaction between fresh benzene and ethylene. Unreacted benzene from guard reactor 2 and a small amount of reaction products are heated through a second heater 63 before entering the bottom of alkylation reactor 1 via benzene feed line 6, where they undergo an alkylation reaction with ethylene entering through upper and lower ethylene feed lines 11 and 12. The benzene-ethylene reaction is exothermic. A hot reaction liquid withdrawal line 13, located in the middle of alkylation reactor 1, can deliver a portion of the hot reaction liquid to the bottom of the guard reactor, providing a heat source. This reduces the heating load of the first heater 42 and reduces energy consumption. When the first guard reactor 2 requires activation, regeneration, or catalyst replacement, the second guard reactor 3 is switched into operation as described above.

[0029] 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 aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features thereof can be replaced by 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 of the various embodiments of the present invention.

Claims

1. An alkylation device for preparing ethylbenzene with a guard reactor, characterized in that: The invention comprises an alkylation reactor and a first guard reactor. The alkylation reactor comprises an upper reaction bed and a lower reaction bed, each of which is equipped with an alkylation catalyst. A benzene feed line is provided at the bottom of the alkylation reactor and a reaction liquid discharge line is provided at the top. An upper ethylene feed line and a lower ethylene feed line are provided at the bottoms of the upper and lower reaction beds, respectively. Both the upper ethylene feed line and the lower ethylene feed line are equipped with compressors for injecting ethylene into the alkylation reactor. The first guard reactor is equipped with a guard reaction bed equipped with a low-temperature catalyst. A fresh benzene feed line and a guard reactor ethylene feed line are provided at the bottom of the first guard reactor. The fresh benzene feed line is equipped with a fresh benzene feed pump and a first heater for heating fresh benzene. The guard reactor ethylene feed line is equipped with a first compressor for injecting ethylene into the guard reactor for reaction. The outlet of the first guard reactor is connected to the benzene feed line, and the benzene feed line is equipped with a second heater.

2. The alkylation device for preparing ethylbenzene with a guard reactor according to claim 1, characterized in that: A hot reaction liquid extraction pipeline is further provided between the upper and lower reaction beds, and a extraction pump is provided on the hot reaction liquid extraction pipeline.

3. The alkylation device for preparing ethylbenzene with a guard reactor according to claim 2, characterized in that: The alkylation ethylbenzene preparation unit of the guard reactor is further provided with a second guard reactor.

4. The alkylation device for preparing ethylbenzene with a guard reactor according to claim 3, characterized in that: A first valve is provided before the hot reaction liquid extraction pipeline enters the first protection reactor, a second valve is provided before the fresh benzene feed pipeline enters the first protection reactor, a third valve is provided before the protection reactor ethylene feed pipeline enters the first protection reactor, and a seventh valve is provided at the outlet of the first protection reactor; a branch is provided on the hot reaction liquid extraction pipeline, and a fourth valve is provided before entering the second protection reactor, a branch is provided on the fresh benzene feed pipeline, and a fifth valve is provided before entering the second protection reactor, a branch is provided on the protection reactor ethylene feed pipeline, and a third valve is provided before entering the second protection reactor, and an eighth valve is provided at the outlet of the second protection reactor.

5. The alkylation device for preparing ethylbenzene with a guard reactor according to claim 3, characterized in that: A first thermometer and a second thermometer are respectively provided at the bottom of the first protection reactor and the second protection reactor.

6. The alkylation device for preparing ethylbenzene with a guard reactor according to claim 5, characterized in that: The first thermometer and the second thermometer are provided with upper and lower limits.

7. The alkylation device for preparing ethylbenzene with a guard reactor according to claim 6, characterized in that: The first thermometer and the second thermometer are electrically connected to the first heater.

8. The alkylation device for preparing ethylbenzene with a guard reactor according to claim 7, characterized in that: A third thermometer is provided at the bottom of the alkylation reactor, and the third thermometer is provided with an upper limit and a lower limit.

9. The alkylation device for preparing ethylbenzene with a guard reactor according to claim 8, characterized in that: The third thermometer is electrically connected to the second heater. When the temperature of the third thermometer is higher than the upper limit, the heating power of the second heater is reduced. When the temperature of the third thermometer is lower than the lower limit, the heating power of the second heater is increased.

10. The alkylation device for preparing ethylbenzene with a guard reactor according to claim 9, characterized in that: A fourth thermometer is provided in the middle of the alkylation reactor. The fourth thermometer is provided with an upper limit and a lower limit. The fourth thermometer is electrically connected to the compressor of the lower ethylene feed pipeline. When the temperature of the fourth thermometer is higher than the upper limit, the ethylene outflow of the compressor of the lower ethylene feed pipeline is reduced. When the temperature of the fourth thermometer is lower than the lower limit, the ethylene outflow of the compressor of the lower ethylene feed pipeline is increased.

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