A device for detecting the activity of a catalyst for a light hydrocarbon catalytic cracking reaction

Abstract

The application relates to a device for detecting the activity of a catalyst in a light hydrocarbon catalytic cracking reaction, which comprises a precise feeding module, a multi-section temperature control reaction module and a recovery analysis module. The multi-section temperature control reaction module comprises a preheating pipe section and a reactor. One end of a feeding pipe is connected with raw materials, and the other end of the feeding pipe is connected with the inlet of the reactor through the preheating pipe section. The preheating pipe section heats the raw materials and then sends the raw materials to the reactor. The reactor comprises a reaction pipe and a loading frame. The loading frame is arranged in the reaction pipe and is provided with a plurality of densely arranged loading holes. The loading holes are suitable for loading the catalyst to be tested. The recovery analysis module comprises a three-stage condensation system and a chromatographic analyzer. The three-stage condensation system performs multi-stage condensation on the products and separates cracking gas. The chromatographic analyzer analyzes the components of the cracking gas. The application can well simulate the reaction environment with high catalyst density in the light hydrocarbon catalytic cracking reaction and accurately evaluate the activity of the catalyst in the light hydrocarbon catalytic cracking reaction.

Description

Technical Field

[0001] This application relates to the field of catalyst evaluation technology, and in particular to an activity detection device for a catalyst used in light hydrocarbon catalytic cracking reaction. Background Technology

[0002] Ethylene, propylene, and other low-carbon olefins are important petrochemical feedstocks. In recent years, light hydrocarbon catalytic cracking technology using C4 and / or C5 hydrocarbons and naphtha as feedstocks has been developed. Compared with heavy oil catalytic cracking technology, light hydrocarbon catalytic cracking uses lighter feedstocks, has a more demanding reaction environment, and further improves the yield of ethylene and propylene.

[0003] There are many differences between light hydrocarbon catalytic cracking units and traditional heavy oil catalytic cracking / catalytic cracking units. Due to the high catalyst density required for light hydrocarbon catalytic cracking technology, the traditional methods for testing the activity of heavy oil catalytic cracking / catalytic cracking catalysts have the following drawbacks when used to test the activity of light hydrocarbon catalytic cracking catalysts: they cannot accurately simulate the harsh reaction conditions of high catalyst density, which will affect the catalyst activity test results. Summary of the Invention

[0004] In view of this, this application proposes an activity detection device for catalysts used in light hydrocarbon catalytic cracking reactions.

[0005] According to one aspect of this application, an activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction is provided, characterized in that it includes: a precision feeding module, a multi-stage temperature-controlled reaction module, and a recovery analysis module;

[0006] The precision feeding module includes: a feeding pipe;

[0007] The multi-stage temperature-controlled reaction module includes: a preheating pipe section and a reactor; one end of the feed pipe is suitable for introducing raw materials, and the other end of the feed pipe is connected to the inlet of the reactor through the preheating pipe section, which is suitable for heating the raw materials and then conveying them to the reactor;

[0008] The reactor includes a reaction pipe and a loading rack; the loading rack is located inside the reaction pipe and has multiple densely arranged loading holes, which are suitable for filling the catalyst to be tested, so that the raw material flows through the catalyst to be tested on the loading rack and reacts with it to generate the product;

[0009] The recovery and analysis module includes a three-stage condensation system and a chromatograph. The reactor outlet is connected to the chromatograph via the three-stage condensation system. The three-stage condensation system is suitable for multi-stage condensation of the product and separation of cracked gas before delivering the cracked gas to the chromatograph. The chromatograph is suitable for component analysis of the cracked gas.

[0010] In one possible implementation, the precision feeding module further includes a nitrogen delivery pipe connected to the feed pipe, which is suitable for delivering nitrogen into the feed pipe.

[0011] In one possible implementation, the reaction pipeline includes: a heating layer, an insulation layer, and a protective layer;

[0012] The insulation layer is attached to the inside of the protective layer, and the heating layer is attached to the inside of the insulation layer.

[0013] In one possible implementation, the multi-stage temperature-controlled reaction module further includes a quench tube section, with the reactor's outlet end connected to the quench tube section's inlet end.

[0014] In one possible implementation, the three-stage condensation system includes: a water-cooled assembly, an ice-water-cooled assembly, and an ethylene glycol-water-cooled assembly connected in sequence.

[0015] In one possible implementation, the water-cooling assembly includes a coaxially arranged spiral tube and an outer tube, one end of the spiral tube being connected to the product, and the medium inlet of the outer tube being suitable for receiving room temperature water, with the room temperature water flowing inside the outer tube to carry away the heat from the product inside the spiral tube.

[0016] In one possible implementation, the ice-water cooling assembly includes: a first water tank and a first transition container, the first transition container being placed inside the first water tank, and one end of a spiral tube extending into the interior of the first transition container to deliver the product into the first transition container; the first water tank is suitable for injecting an ice-water mixture.

[0017] In one possible implementation, the ethylene glycol water cooling assembly includes: a second water tank and a second transition container, the second transition container being placed inside the second water tank, and a first transition container being connected to the second transition container via a delivery pipe to deliver the product to the interior of the second transition container; the second water tank is suitable for being injected with an aqueous ethylene glycol solution.

[0018] In one possible implementation, the recovery analysis module also includes a cracked gas collection bottle.

[0019] Beneficial Effects: The main function of the preheating section is to heat and gasify the raw materials. The reactor is the core component of the entire device, where the gasified raw materials from the preheating section undergo catalytic cracking under the action of the catalyst under test, generating products. The recovery and analysis module mainly performs rapid condensation and separation of the products and real-time online analysis of the cracked gas within the products. The densely arranged filling holes on the reactor are suitable for filling the catalyst under test, simulating the high-density distribution structure of the catalyst in actual catalytic reactions, thereby accurately simulating reaction conditions, improving detection accuracy, and reducing experimental result errors. Through this application, the activity of the catalyst under test in the catalytic cracking reaction of light hydrocarbons can be accurately evaluated, and the performance of the evaluation device can be optimized to achieve the goals of minimal material loss and minimal catalyst activity detection error.

[0020] Other features and aspects of this application will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0021] The accompanying drawings, which are included in and form part of this specification, illustrate exemplary embodiments, features, and aspects of this application together with the specification and serve to explain the principles of this application.

[0022] Figure 1 This diagram illustrates the structural connection of an activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction according to an embodiment of this application.

[0023] Figure 2 A cross-sectional view of a multi-segment temperature-controlled reaction module according to an embodiment of this application is shown;

[0024] Figure 3 A top view of the loading rack according to an embodiment of this application is shown;

[0025] Figure 4 This diagram illustrates the structure of the recycling analysis module according to an embodiment of this application. Detailed Implementation

[0026] Various exemplary embodiments, features, and aspects of this application will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0027] It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model or simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0028] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0029] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0030] Furthermore, to better illustrate this application, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this application can be implemented without certain specific details. In some instances, methods, means, components, and circuits well-known to those skilled in the art have not been described in detail in order to highlight the main points of this application.

[0031] Figure 1 This diagram illustrates the structural connection of an activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction according to an embodiment of this application. Figure 2 A cross-sectional view of a multi-segment temperature-controlled reaction module according to an embodiment of this application is shown; Figure 3 A top view of the loading rack according to an embodiment of this application is shown; Figure 4 This diagram illustrates the structure of the recycling analysis module according to an embodiment of this application. Figure 1As shown, the activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction includes: a precision feed module 100, a multi-stage temperature-controlled reaction module 200, and a recovery analysis module 300; the precision feed module 100 includes: a feed pipe 130; the multi-stage temperature-controlled reaction module 200 includes: a preheating pipe section 210 and a reactor 220; one end of the feed pipe 130 is suitable for introducing raw materials, and the other end of the feed pipe 130 is connected to the inlet of the reactor 220 through the preheating pipe section 210, which is suitable for heating the raw materials and then conveying them to the reactor 220; the reactor 220 includes: a reaction pipe and a loading rack 500; the loading rack 500... The loading rack 500, located inside the reaction pipeline, has multiple densely arranged loading holes 540. The loading holes 540 are suitable for filling the catalyst to be tested, so that the raw material flows through the catalyst to be tested on the loading rack 500 and reacts with it to generate the product. The recovery analysis module 300 includes a three-stage condensation system 310 and a chromatograph 330. The outlet of the reactor 220 is connected to the chromatograph 330 through the three-stage condensation system 310. The three-stage condensation system 310 is suitable for multi-stage condensation of the product and separation of cracked gas, and then the cracked gas is delivered to the chromatograph 330. The chromatograph 330 is suitable for component analysis of the cracked gas.

[0032] It should be noted that the main function of the preheating section 210 is to heat and gasify the raw material. The reactor 220 is the core part of the entire device, and its function is to carry out catalytic cracking reaction of the raw material heated and gasified from the preheating section 210 under the action of the catalyst to be tested within the reactor 220. The recovery and analysis module 300 mainly completes the rapid condensation and separation of the products and real-time online analysis. The densely arranged filling holes on the reactor 220 are suitable for filling the catalyst to be tested, simulating the high density distribution of the catalyst in the actual catalytic reaction, so as to accurately simulate the reaction conditions, improve the detection accuracy, and reduce the error of the experimental results. Through this application, the activity of the catalyst to be tested in the catalytic cracking reaction of light hydrocarbons can be accurately evaluated, providing reliable data support for the research and development of the catalyst to be tested, and the operation and optimization of industrial equipment. The performance of the evaluation device is optimized through modular design to achieve the goal of small material loss and small catalyst activity detection error.

[0033] In one possible implementation, the precision feeding module 100 further includes a nitrogen delivery pipe 140, one end of which is connected to the feed pipe 130, and the other end of which is connected to a nitrogen tank 150. This allows nitrogen to enter the feed pipe 130 at a certain flow rate. Nitrogen is introduced into the feed pipe 130 as a purge gas. Nitrogen's chemical stability ensures that there are no impurities other than nitrogen in the pipe, maintaining a pure reaction environment. It also carries all reaction products to the recovery and analysis module 300, ensuring that no products remain in the pipe. Combined with the rapid cooling design of the reaction module, this significantly improves the recovery rate of the reaction products, meeting the stringent requirements for material recovery.

[0034] In one possible implementation, the multi-stage temperature-controlled reaction module 200 further includes a raw material storage tank 110, with the inlet end of the feed pipe 130 connected to the interior of the raw material storage tank 110. The raw material storage tank 110 is suitable for storing sealed raw materials, ensuring that the raw materials will not evaporate or be lost, and ensuring the integrity and stability of the experimental raw materials. A diaphragm metering pump 120 is provided on the feed pipe 130, which can accurately control the feed rate and feed amount of the experimental raw materials, providing a stable and accurate supply of raw materials for the reaction.

[0035] In one possible implementation, the preheating section 210 includes: a first spiral tube 400 and a first outer tube arranged coaxially. The first spiral tube 400 is disposed inside the first outer tube. The outlet end of the feed pipe 130 is connected to one end of the first spiral tube 400, thereby conveying the raw material into the first spiral tube 400. The spiral coil design significantly extends the residence time of the raw material in the first spiral tube 400, thereby ensuring that the raw material can be fully preheated to the required temperature. The first outer tube includes: a first heating layer 430, a first insulation layer 420, and a first protective layer 410 stacked sequentially from the inside to the outside. The first heating layer 430 uses a furnace tile with an electric heating wire to heat the raw material. The electric heating wire is linked with a PID temperature control module, which can accurately control the preheating temperature between 400-500℃, with temperature fluctuations of less than 5℃, providing stable preheated raw material for subsequent reactions. The first insulation layer 420 is suitable for effectively reducing heat loss and ensuring heating efficiency. The first protective layer 410 serves as protection and support.

[0036] Furthermore, the main body of the first insulation layer 420 is a circular tube structure, and the material of the first insulation layer 420 is aluminum silicate fiber, with a thickness ranging from 10 to 15 cm.

[0037] Furthermore, the main body of the first protective layer 410 is a cylindrical shell structure with a cavity, and both the upper and lower ends are provided with through holes for the first spiral tube 400 to enter and exit, and the first heating layer 430 and the first heat insulation layer 420 inside are sealed; preferably, the material of the first protective layer 410 is stainless steel, and the thickness of the first protective layer 410 is in the range of 0.8-1.2mm.

[0038] In one possible implementation, the reaction pipeline includes: a second heating layer 530, a second insulation layer 520, and a second protective layer 510 stacked sequentially from the inside out; wherein the second heating layer 530 is made of a furnace tile with an electric heating wire, which heats the raw materials through the heat generated by the electric heating wire. The electric heating wire is linked with a PID temperature control module to control the temperature of the reactor 220 between 600-700℃, with temperature fluctuations of less than 2℃, ensuring that the reaction takes place in a stable and compliant high-temperature environment, meeting the strict requirements for reaction temperature in light hydrocarbon catalytic cracking; the second insulation layer 520 is suitable for effectively reducing heat loss and ensuring heating efficiency; the second protective layer 510 serves as protection and support.

[0039] Furthermore, the main body of the second insulation layer 520 is a circular tube structure, and the material of the second insulation layer 520 is aluminum silicate fiber, with a thickness ranging from 10 to 15 cm.

[0040] Furthermore, the main body of the second protective layer 510 is a cylindrical shell structure with a cavity, and both the upper and lower ends are provided with clearance holes that are opposite to the two ends of the loading frame 500 so that the raw material in the first spiral tube 400 can enter the loading frame 500. The second protective layer 510 can seal the internal second heating layer 530 and second insulation layer 520. Preferably, the material of the second protective layer 510 is stainless steel, and the thickness of the second protective layer 510 is in the range of 0.8-1.2mm.

[0041] The main body of the loading rack 500 is cylindrical. The length direction of the loading rack 500 is parallel to the length direction of the reaction pipeline, and the central axis of the loading rack 500 is on the same straight line as the central axis of the reaction pipeline. The loading rack 500 has multiple loading holes 540, and each loading hole 540 vertically penetrates the opposite ends of the loading rack 500. The loading holes 540 are suitable for filling the catalyst to be tested.

[0042] Preferred, such as Figure 3 As shown, the cross-section of each filling hole 540 is a regular hexagonal structure, and all filling holes 540 are arranged in a honeycomb structure. The filling density of the catalyst to be tested in the filling rack 500 ranges from 200 to 400 g / L.

[0043] Preferably, the diameter of a single filling hole 540 is 1-3 mm.

[0044] In one possible implementation, the catalyst to be tested is a microsphere with an average particle size of 60-80 micrometers. To prevent the catalyst to be tested from flowing into the quench section with the reaction products, a metal filter screen is installed at the bottom outlet of the reaction pipeline to support the catalyst to be tested in the loading rack 500 without interfering with the flow of products into the quench section 230.

[0045] Preferably, the catalyst to be tested can be a molecular sieve catalyst, a metal oxide catalyst, or a mixture of the two.

[0046] Traditional catalytic cracking uses riser reactors with catalyst densities of less than 100 g / L; while the catalyst density for light oil catalytic cracking needs to be between 200-400 g / L, far exceeding that of conventional catalytic cracking. This application can provide a larger catalyst density during catalyst activity testing, better simulating the reaction environment of light oil catalytic cracking.

[0047] Preferably, the loading rack 500 is made of ceramic; this gives the loading rack 500 good high-temperature resistance and chemical stability, and enables it to uniformly distribute the catalyst to be tested according to the preset density requirements, ensuring the sufficiency and consistency of the reaction.

[0048] In one possible implementation, the multi-stage temperature-controlled reaction module 200 further includes a quench section 230, with the discharge end of the reactor 220 connected to the inlet end of the quench section 230. It should be noted that the key function of the quench section 230 is to indirectly exchange heat between the product from the reactor 220 and air or water, thereby rapidly terminating the reaction.

[0049] Furthermore, the quenching section 230 includes a second spiral tube 600 and a second outer tube arranged coaxially. The spiral coil design extends the residence time of the product in the second spiral tube 600, ensuring that the reaction product can be sufficiently cooled to the required temperature. The second outer tube includes a jacket 620 and a shell 610. The jacket 620 is suitable for conveying the quenching medium, which flows inside the cavity of the jacket 620 and indirectly exchanges heat with the product in the second spiral tube 600, achieving rapid cooling of the product. The shell 610 is a cylindrical barrel made of stainless steel, with through holes at both ends for the second spiral tube 600 to pass through, providing protection and support. This design enables efficient quenching of the reaction product, controlling the temperature of the cooled product at 100-200℃, effectively reducing the occurrence of secondary reactions, improving the authenticity and accuracy of data, and effectively reducing the loss of reaction products.

[0050] Since the temperature of the product stream from reactor 220 reaches over 600°C, direct water cooling would generate water vapor, which would affect the safety of the testing device. Therefore, the cooling tube section 230 adopts a combination of direct air cooling and indirect water cooling. Passing water through the jacket 620 can increase the air cooling effect.

[0051] In one possible implementation, the three-stage condensation system 310 includes a water-cooling component, an ice-water-cooling component, and an ethylene glycol-water-cooling component connected in sequence. The product (cracked gas) from the reaction module undergoes staged condensation through the three-stage condensation system 310, which consists of water cooling, ice-water cooling, and ethylene glycol-water cooling. The water cooling stage uses room-temperature water to initially cool the product; the ice-water-cooling stage further lowers the temperature, condensing high-boiling-point substances (heavy distillate components); and the ethylene glycol-water-cooling stage lowers the temperature even further, condensing low-boiling-point substances (C5+ light components). This three-stage condensation method enables efficient separation of products with different boiling points, ensuring that the cracked gas product is free of liquid and improving the purity and recovery efficiency of the target product.

[0052] In one possible implementation, the water-cooling assembly includes: a third spiral tube 900 and a third outer tube 910 arranged coaxially; the third spiral tube 900 is located inside the third outer tube 910, one end of the third spiral tube 900 is connected to the outlet end of the second spiral tube 600 to receive the product, and the other end of the third spiral tube 900 is connected to the first transition container 710 of the ice-water cooling assembly; the medium inlet of the third outer tube 910 is suitable for receiving room temperature water, and the room temperature water flows in the third outer tube 910 to remove the heat of the product in the third spiral tube 900.

[0053] Furthermore, the main body of the first protective layer 410 is a barrel-shaped structure with a cavity, and both the upper and lower ends are provided with through holes for the third spiral tube 900 to enter and exit.

[0054] In one possible implementation, the ice-water cooling assembly includes: a first water tank 700 and a first transition container 710. The first transition container 710 is placed inside the cavity of the first water tank 700. One end of a third spiral tube 900 extends into the cavity of the first transition container 710 to transport the product into the first transition container 710. The first water tank 700 is suitable for being injected with an ice-water mixture of 0-5°C, and the product in the first transition container 710 is cooled and de-temperatured under the low temperature effect of the ice-water mixture.

[0055] In one possible implementation, the ethylene glycol water cooling assembly includes: a second water tank 800 and a second transition container 810. The second transition container 810 is placed inside the cavity of the second water tank 800. A first transition container 710 is connected to the second transition container 810 through a first delivery pipe 720 to deliver the product into the cavity of the second transition container 810. The second water tank 800 is suitable for being injected with an ethylene glycol aqueous solution at -10°C, and the product in the second transition container 810 is cooled down again under the low temperature effect of the ethylene glycol aqueous solution.

[0056] Furthermore, both the first transition container 710 and the second transition container 810 are made of glass, and their volume ranges from 100 to 200 ml.

[0057] In one possible implementation, the recovery analysis module 300 further includes a cracked gas collection bottle 320 and a brine bottle 340, with the cracked gas collection bottle 320 filled with saturated brine. A second transition container 810 is connected to the cracked gas collection bottle 320 via a second conveying pipe 820 to transport the products into the interior of the cracked gas collection bottle 320. A third conveying pipe is provided on the side wall of the cracked gas collection bottle 320, with one end connected to the interior of the cavity of the cracked gas collection bottle 320 and the other end connected to the interior of the cavity of the brine bottle 340. It should be noted that the reaction products include cracked gas, liquid products, and coke; the coke is negatively deposited on the catalyst, the liquid products (including unconverted raw materials) are stored in the first transition container 710 and the second transition container 810, while the cracked gas is stored in the cracked gas collection bottle 320. By collecting data on the cracked gas, liquid products, and coke, the material balance and material loss of the reaction can be calculated, and the catalyst activity can be further calculated. During the test, the cracked gas is collected in a cracked gas collection bottle 320 filled with saturated saline solution, while the saturated saline solution is discharged into a saline bottle 340. The volume of the cracked gas can be calculated by weighing the change in weight of the saline bottle 340. Then, based on the temperature of the cracked gas and the composition data obtained from chromatographic analysis, the weight of the cracked gas and the yields of ethylene, propylene, and butene can be calculated.

[0058] In one possible implementation, the recovery analysis module 300 further includes a chromatograph 330; the cracked gas collection bottle 320 is connected to the inlet of the chromatograph 330 via a fourth delivery pipe to deliver the product to the chromatograph 330 for analysis. The chromatograph 330 can perform real-time component analysis of the cracked gas, thereby evaluating the activity data of the catalyst under test. By accurately detecting the content and proportion of each component in the cracked gas, it can quickly and accurately obtain the activity performance of the catalyst under test in the catalytic cracking reaction of light hydrocarbons, providing direct and reliable data support for the performance evaluation of the catalyst under test.

[0059] Preferably, the chromatograph 330 uses an Agilent 8890 gas chromatograph.

[0060] The testing process for this application is as follows:

[0061] 1. Preparation stage

[0062] First, the catalyst sample to be tested is loaded into the loading rack 500 of reactor 220.

[0063] Check whether the connections of each component of the multi-stage temperature control reaction module 200 and the recovery analysis module 300 are secure, and whether there is a risk of leakage in each pipeline.

[0064] Add an appropriate amount of feed material to the raw material storage tank 110. Naphtha or n-hexane and other light hydrocarbon feed materials can be selected according to experimental requirements.

[0065] Check and ensure that the nitrogen tank 150 is filled with nitrogen and that the quenching medium (water or air) supply to the quenching pipe section 230 is normal.

[0066] The preheating temperature of the preheating tube section 210 is set to 450℃ (which can be adjusted within the range of 400-500℃ according to experimental requirements), the temperature of the reactor 220 is maintained at 650℃ (which can be adjusted within the range of 600-700℃ according to experimental requirements), and the cooling temperature of the quenching tube section 230 is set to 150℃ (which can be adjusted within the range of 100-200℃ according to experimental requirements).

[0067] Start the three-stage condensation system 310: inject room temperature water at 10-25℃ into the water-cooling components; inject a mixture of ice and water at 0-5℃ into the first water tank 700 to condense the heavy distillation components in the products; inject an ethylene glycol aqueous solution (40% concentration) at -10℃ into the second water tank 800 to condense the C5+ light components in the products, so that the cracked gas sample does not contain components above C5.

[0068] Turn on the chromatograph 330 and calibrate it with a standard sample.

[0069] 2. Experimental Phase

[0070] The nitrogen supply device is turned on, allowing nitrogen to enter the system at a certain flow rate as a purge gas to remove other impurities from reactor 220. After reaching the predetermined preheating and reaction temperatures, the diaphragm metering pump 120 is turned on, and the raw materials are transported from the sealed raw material storage tank 110 to the multi-stage temperature-controlled reaction module 200 at a preset feed rate for raw material preheating, catalytic cracking reaction, and product rapid cooling. After the raw material feeding is terminated, nitrogen is reintroduced into the system at a certain flow rate as a purge gas to transport the reaction products to the subsequent recovery and analysis module 300.

[0071] In the preheating section 210, the raw material is heated and vaporized in the first spiral tube 400, and enters the reactor 220 after reaching the preset preheating temperature.

[0072] In reactor 220, the gasified feedstock comes into full contact with the catalyst to be tested, which is packed on the loading rack 500, and undergoes a catalytic cracking reaction at a high temperature. During the reaction, the temperature of the reaction section is monitored and adjusted in real time by a PID temperature control module to ensure stable reaction.

[0073] The reaction products enter the quench section 230 from the reactor 220. In the quench section 230, the products are rapidly cooled to the preset temperature by indirect heat exchange with the quench medium in the jacket 620.

[0074] The cooled product enters the recovery and analysis module 300, and sequentially passes through a three-stage condensation system 310 consisting of water cooling, ice-water cooling, and ethylene glycol water cooling. Products with different boiling points are condensed and separated at each stage. The separated liquid product is collected in corresponding containers (first transition container 710, second transition container 810), while the cracked gas enters the cracked gas collection bottle 320 and is analyzed in real time by an online cracked gas chromatograph 330.

[0075] 3. Data recording and analysis stage

[0076] During the experiment, the operating parameters of each module were recorded in real time, including feed rate, feed volume, reaction temperature, preheating temperature, quenching temperature, nitrogen flow rate, and the volume and temperature of cracked gas.

[0077] The 330 online cracked gas chromatograph analyzes the composition data of cracked gas in real time, recording the content and proportion of each component. Based on this data, the activity index of the catalyst under test and the olefin content in the cracked gas are calculated.

[0078] It's important to note that two main factors need to be considered in light oil catalytic cracking units: the feedstock conversion rate and the yields of ethylene and propylene. These factors are closely related to the amount of cracked gas and the concentrations of ethylene and propylene within it. Different feedstocks and product requirements necessitate different catalyst activity. If the activity is too high, the yields of low-value byproducts such as methane and coke will be too high, impacting the unit's economic efficiency. Conversely, if the activity is too low, the feedstock conversion rate will be too low, resulting in low yields of the target products, ethylene and propylene, also affecting the unit's economic efficiency. The olefin content in the cracked gas does not have a monotonically increasing relationship with catalyst activity; therefore, higher catalyst activity is not always better and requires comprehensive consideration.

[0079] After the experiment, the collected liquid products were weighed and their composition was analyzed offline. Combined with cracked gas data and carbon determination data of the tested catalyst, the material balance of the experiment was calculated. By comparing and analyzing data from multiple experiments, the activity performance of the tested catalyst under different conditions was evaluated, providing data support for the research and optimization of the tested catalyst.

[0080] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. An activity detection device for a catalyst used in the catalytic cracking reaction of light hydrocarbons, characterized in that, include: Precision feeding module, multi-stage temperature-controlled reaction module, and recovery analysis module; The precision feeding module includes: a feeding pipe; The multi-stage temperature-controlled reaction module includes: a preheating pipe section and a reactor; one end of the feed pipe is suitable for introducing raw materials, and the other end of the feed pipe is connected to the inlet of the reactor through the preheating pipe section, and the preheating pipe section is suitable for heating the raw materials and then conveying them to the reactor; The reactor includes a reaction pipe and a loading rack; the loading rack is disposed inside the reaction pipe and has a plurality of densely arranged loading holes, the loading holes being suitable for filling with a catalyst to be tested, so that the raw material flows through the catalyst to be tested on the loading rack and reacts with it to generate a product; The recovery and analysis module includes a three-stage condensation system and a chromatograph. The outlet of the reactor is connected to the chromatograph through the three-stage condensation system. The three-stage condensation system is suitable for multi-stage condensation of the product and separation of cracked gas, and then delivering the cracked gas to the chromatograph. The chromatograph is suitable for component analysis of the cracked gas.

2. The apparatus for detecting the activity of a catalyst for a light hydrocarbon catalytic cracking reaction according to claim 1, wherein The precision feeding module further includes a nitrogen delivery pipeline, which is connected to the feeding pipeline and is suitable for delivering nitrogen into the feeding pipeline.

3. The apparatus for detecting the activity of a catalyst for a light hydrocarbon catalytic cracking reaction according to claim 1, wherein The reaction pipeline includes: a heating layer, an insulation layer, and a protective layer; The insulation layer is attached to the inside of the protective layer, and the heating layer is attached to the inside of the insulation layer.

4. The activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction according to claim 1, characterized in that, The multi-stage temperature-controlled reaction module further includes a quenching section, wherein the discharge end of the reactor is connected to the inlet end of the quenching section.

5. The activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction according to claim 1, characterized in that, The three-stage condensation system includes: a water-cooled component, an ice-water-cooled component, and an ethylene glycol-water-cooled component connected in sequence.

6. The activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction according to claim 5, characterized in that, The water-cooling assembly includes a spiral tube and an outer tube arranged coaxially. One end of the spiral tube is connected to the product, and the medium inlet of the outer tube is suitable for receiving room temperature water. The room temperature water flows in the outer tube and carries away the heat of the product in the spiral tube.

7. The activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction according to claim 6, characterized in that, The ice-water cooling assembly includes: a first water tank and a first transition container, wherein the first transition container is placed inside the first water tank, and one end of the spiral tube extends into the interior of the first transition container to transport the product into the first transition container; the first water tank is suitable for injecting an ice-water mixture.

8. The activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction according to claim 7, characterized in that, The ethylene glycol water cooling assembly includes: a second water tank and a second transition container, the second transition container being placed inside the second water tank, and the first transition container being connected to the second transition container via a delivery pipe to deliver the product to the interior of the second transition container; the second water tank is suitable for being injected with an aqueous ethylene glycol solution.

9. The activity detection device for a catalyst used in a light hydrocarbon catalytic cracking reaction according to claim 1, characterized in that, The recovery analysis module also includes a cracked gas collection bottle.

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