CN210058196U

CN210058196U - Fixed bed reactor for producing hydrocarbons

Info

Publication number: CN210058196U
Application number: CN201920400699.9U
Authority: CN
Inventors: 孙丽丽; 王振维; 盛在行; 刘罡; 丁利伟; 李少鹏; 聂毅强; 赵百仁
Original assignee: China Petroleum and Chemical Corp; Sinopec Engineering Inc
Current assignee: China Petroleum and Chemical Corp; Sinopec Engineering Inc
Priority date: 2019-03-27
Filing date: 2019-03-27
Publication date: 2020-02-14
Anticipated expiration: 2029-03-27

Abstract

The utility model belongs to the petrochemical field relates to a fixed bed reactor of production hydrocarbon. The fixed bed reactor is a downflow reactor adopting a plurality of sections of catalyst bed layers connected in series, 1-3 stages of heat taking measures are arranged between two adjacent sections of catalyst bed layers, wherein at least 1 stage of heat taking measures adopts a coil heat exchanger; at least one section of catalyst bed layer is provided with an injection port. Adopt the utility model discloses a scheme can guarantee that the reaction condition of every section bed all is in suitable within range, has both improved the overall yield of target product and also does benefit to operation and control.

Description

Fixed bed reactor for producing hydrocarbons

Technical Field

The utility model belongs to the petrochemical field, more specifically relates to a fixed bed reactor of production hydrocarbon.

Background

Ethylene is one of the chemical products with the largest yield in the world, the ethylene industry is the core of the petrochemical industry, and the ethylene product accounts for more than 75 percent of petrochemical products and occupies an important position in national economy. Ethylene production has been used worldwide as one of the important indicators for the development of petrochemical in one country.

With the large fluctuation of the international crude oil price and the technical progress, in order to change the condition that the raw materials for producing ethylene depend on petroleum resources excessively, the raw materials for producing ethylene are changed, and the technology for producing ethylene by taking methanol as the raw material is developed and becomes a technology with wide industrial application in the novel coal chemical industry technology.

The technology for preparing ethylene by Oxidative Coupling of Methane (OCM) is an important technology for producing ethylene, takes natural gas as a raw material, can prepare ethylene by only one-step reaction process, and has high theoretical value and economic value. After more than 30 years of research, the research on ethylene preparation by a methane one-step method has made a breakthrough, and the industrial demonstration device for preparing ethylene by methane coupling is successfully put into production, which is moving towards the beginning of industrialization. The method has great significance for breaking the bottleneck of raw material sources in the ethylene industry, reducing the production cost and enhancing the competitiveness of the ethylene industry and downstream industries.

Research and development at home and abroad are most typical of Siluria technology company in the United states, and the Siluria develops an industrially feasible methane direct ethylene catalyst by precisely synthesizing a nanowire catalyst by using a biological template. The catalyst can efficiently catalyze the conversion of methane into ethylene under the condition of 200-300 ℃ lower than the operation temperature of the traditional steam cracking method and under the pressure of 5-10 atmospheric pressures. The technology prolongs the service life of the catalyst, greatly reduces the operation temperature, but has no substantial breakthrough on the conversion rate of methane and the yield of ethylene.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a fixed bed reactor of production hydrocarbons, specifically for providing a reliable with methane transformation for richly contain the technical scheme of the product of components such as high added value hydrocarbons such as ethylene.

In order to achieve the above object, the present invention provides a fixed bed reactor for producing hydrocarbons, which is a downflow reactor using a plurality of catalyst beds connected in series, wherein 1-3 stages of heat extraction measures are arranged between two adjacent catalyst beds, wherein at least 1 stage of heat extraction measure is a coil heat exchanger; at least one section of catalyst bed layer is provided with an injection port.

Furthermore, the number of the sections of the multi-section catalyst bed layer is 2-6.

Further, the position of the heat removal means is located outside the catalyst bed.

Further, the position of the heat removal means is located inside the catalyst bed.

Further, the injection port is disposed adjacent to the catalyst bed.

Further, the injection port is arranged at a position that the residence time of the material injected by the injection port from the injection to the catalyst bed layer is not more than 100 ms.

Further, the injection opening is arranged at a position that the residence time of the material injected by the injection opening from the injection to the catalyst bed layer is not more than 50 ms.

Furthermore, the middle part of at least one section of the catalyst bed layer is also provided with an injection port.

Further, a heat insulation structure is arranged in the fixed bed reactor; for separating a high temperature region from a low temperature region.

The beneficial effects of the utility model reside in that: the reaction conditions of each section of bed layer can be ensured to be in a proper range, thereby not only improving the overall yield of the target product, but also being beneficial to operation and control. Due to the arrangement of a special heat taking means, the reaction condition can be controlled, and meanwhile, the system can be used for timely heat removal when the reaction generates temperature runaway, so that the safety of the system is improved. Furthermore, the utility model discloses avoided complicated heat transfer part, adopted simple structure's coil heat exchanger, reduced equipment cost.

Other features and advantages of the present invention will be described in detail in the detailed description which follows.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings.

FIG. 1 shows a schematic diagram of a reaction scheme in which the reaction raw materials are methane and oxygen, and three-stage reaction is carried out with inter-stage oxygen supplementation.

FIG. 2 is a schematic diagram showing a reaction scheme of two-stage reaction of methane and oxygen as reaction raw materials and provided with interstage methane and oxygen supplementation.

FIG. 3 shows a schematic diagram of a reaction scheme in which reaction raw materials are methane and oxygen, two-stage reaction is carried out, and the reaction scheme is provided with interstage methane supplement and oxygen and steam temperature control.

FIG. 4 shows a schematic diagram of a reaction scheme of two-stage reaction with methane and oxygen as reaction raw materials and with interstage methane, oxygen and ethane supplementation.

Description of the reference numerals

S1, raw material gas; s2, boiler water supply; s3, steam; s4, oxygen; s5, reacting product gas; s6, methane and oxygen; s7, water vapor; s8, ethane.

1. A catalyst bed layer; 2. a coil heat exchanger; 3. and (4) injecting the liquid into the opening.

Detailed Description

Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be construed as limited to the embodiments set forth herein.

The utility model provides a fixed bed reactor for producing hydrocarbons, which is a downflow reactor adopting a plurality of sections of catalyst bed layers connected in series, wherein 1-3 levels of heat taking measures are arranged between two adjacent sections of catalyst bed layers, and at least 1 level of heat taking measures is a coil heat exchanger; at least one section of catalyst bed layer is provided with an injection port.

Furthermore, the number of the sections of the multi-section catalyst bed layer is 2-6. According to the utility model discloses, "between two sections adjacent catalyst bed" both include the space outside two sections adjacent catalyst bed, also include the inside space of catalyst bed, consequently, the implementation position of getting the heat measure can be located catalyst bed outside, also can be located catalyst bed inside.

The utility model discloses in, get hot measure and can be the heat exchanger, used heat getting medium can be selected from at least one of following material: water, steam, raw gas, reaction product gas, inert substances and molten salt.

According to the utility model, the injection port is arranged at the position of at least one section of catalyst bed layer. When the injection port is used for sectional feeding or sectional oxygen supply, the injection ports can be arranged at all catalyst bed layers, or at all other catalyst bed layers except the first catalyst bed layer; the injection material may comprise oxygen-enriched gas and optionally: methane-rich gas, CO, inert gas and water. In this case, the injection port is preferably disposed close to the catalyst bed, and the term "close to the catalyst bed" includes both a position outside the catalyst bed and a position inside the catalyst bed. In particular, the injection port is positioned such that the residence time of the material injected by the injection port from injection to the arrival at the catalyst bed is not more than 100ms, preferably not more than 50 ms. Compare and set up in the mode of reactor entrance, will the filling opening sets up and to realize the control to process conditions better near catalyst bed department, improves methane conversion and ethylene selectivity then, through this setting, can minimize the contact time of methane outside catalyst bed layer in oxygen and the feed gas, reduces methane combustion volume, avoids extravagant material, can effectively control the temperature rise simultaneously.

When the injection port is used for injecting ethane and coupling with an OCM process, the injection port is preferably arranged in the middle of the catalyst bed layer, ethane absorbs heat released by oxidative coupling reaction to crack, and the two reactions are carried out in the same catalyst bed layer, so that the temperature of the oxidative coupling reaction of methane can be controlled, and the yield of olefin is improved.

According to the utility model, preferably, a heat insulation structure is arranged in the fixed bed reactor; the heat insulation structure can use refractory materials as main construction materials, the refractory materials can be selected from corundum refractory bricks and the like, and a high-temperature area in the reactor is separated from a low-temperature area such as an outer wall, a heat extraction structure and a pipeline.

Example 1

Adopting a fixed bed reactor as shown in figure 1, wherein the fixed bed reactor is a down-flow reactor adopting 3 sections of catalyst bed layers 1 connected in series, and 3-stage heat taking measures are arranged between two adjacent sections of catalyst bed layers, wherein the 1 st-stage heat taking measure is positioned in the catalyst bed layers and used for taking heat for a heat exchanger (not shown), the used heat taking medium is water, the 2 nd-stage heat taking measure is positioned in the catalyst bed layers and used for taking heat for directly injecting low-temperature materials (not shown), and the used low-temperature materials are water vapor; the 3 rd stage heat taking measure is positioned outside the catalyst bed layer, the heat is taken by adopting a coil heat exchanger 2, the feed in the coil heat exchanger 2 is boiler feed water S2, and the discharge is steam S3; and the second section of catalyst bed layer and the third section of catalyst bed layer are both provided with injection ports 3, and the injection ports 3 are arranged close to the catalyst bed layer 1. A heat insulation structure (not shown) is arranged in the fixed bed reactor and used for separating a high-temperature region from a low-temperature region;

specifically, natural gas (wherein the methane content is 95%) is mixed with oxygen to form feed gas S1, and the mixing temperature is 650 ℃; carrying out oxidative coupling reaction in a fixed bed reactor under the action of an OCM catalyst to obtain a catalyst containing at least CO and CO₂Ethylene, ethane, ethylene,Reaction product gas S5 containing carbon three or more, wherein at least one of unreacted methane, generated CO and ethane in the reaction product gas S5 returns to the reaction system to continuously participate in the reaction; the raw material gas S1 flows from top to bottom, and the volume space velocity is 10000h^-1The temperature of the oxidative coupling reaction is 800 ℃, the pressure is 0.15MPaG, and the volume ratio of methane to oxygen at the inlet of each section of bed layer is 1.2: 1; the injection port injects oxygen S4, and the residence time of oxygen from injection to bed is 80 ms.

In this example, the methane conversion was 30% and the ethylene selectivity was 60%.

Example 2

The difference from example 1 is that a fixed bed reactor as shown in FIG. 2 was used. The reactor adopts 2 sections of catalyst bed layers 1 which are connected in series, an injection port 3 is arranged at the position close to the second section of catalyst bed layer, the injected materials are methane and oxygen S6, and the retention time of the oxygen from the injection to the bed layer is 90 ms.

Example 3

The difference from example 1 is that a fixed bed reactor as shown in FIG. 3 was used. The reactor adopts 2 sections of catalyst bed layers 1 which are connected in series, the 2 nd-stage heat taking measure is positioned outside the catalyst bed layers, the coil heat exchanger 2 is adopted for heat taking, the 3 rd-stage heat taking measure is used for directly injecting low-temperature materials for heat taking, the used low-temperature materials are water vapor S7, an injection port 3 is arranged at the position close to the second section of catalyst bed layers, the injected materials are methane and oxygen S6, and the retention time of the oxygen from the injection to the bed layers is 40 ms.

In this example, the methane conversion was 35% and the ethylene selectivity was 65%.

Example 4

The difference from example 2 is that a fixed bed reactor as shown in FIG. 4 was used. And the middle parts of the two catalyst bed layers are respectively provided with an injection port for injecting ethane. Ethane absorbs the heat released by the oxidative coupling reaction to carry out cracking.

In this example, the methane conversion was 25%, the ethylene selectivity yield was 60%, and the bed temperature rise was 70 ℃.

While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A fixed bed reactor for producing hydrocarbons is characterized in that the fixed bed reactor is a downflow reactor adopting a plurality of sections of catalyst bed layers connected in series, 1-3 stages of heat extraction measures are arranged between two adjacent sections of catalyst bed layers, wherein at least 1 stage of heat extraction measure is a coil heat exchanger; at least one section of catalyst bed layer is provided with an injection port.

2. The fixed bed reactor for producing hydrocarbons according to claim 1, wherein the number of stages of the multi-stage catalyst bed is 2 to 6 stages.

3. Fixed bed reactor for the production of hydrocarbons according to claim 1, characterised in that the location of the heat removal means is outside the catalyst bed.

4. Fixed bed reactor for the production of hydrocarbons according to claim 1, characterised in that the location of the heat removal means is inside the catalyst bed.

5. The fixed bed reactor for producing hydrocarbons as claimed in claim 1, wherein said injection port is located adjacent to the catalyst bed.

6. The fixed bed reactor for producing hydrocarbons according to claim 5, wherein the injection port is positioned such that the residence time of the material injected by the injection port from the injection to the catalyst bed is not more than 100 ms.

7. The fixed bed reactor for producing hydrocarbons according to claim 6, wherein the injection port is positioned such that the residence time of the material injected by the injection port from the injection to the catalyst bed is not more than 50 ms.

8. The fixed bed reactor for producing hydrocarbons according to claim 1, wherein at least one section of the catalyst bed is further provided with an injection port in the middle.

9. The fixed bed reactor for producing hydrocarbons as claimed in claim 1, wherein a thermal insulation structure is provided in the fixed bed reactor; for separating a high temperature region from a low temperature region.