Method for identifying loss of catalyst in regeneration system of catalytic cracking unit
By quantifying the particle size distribution statistics of the balance agent and regenerated flue gas in the catalytic cracking device regeneration system, the problem of difficult to judge the catalyst loss is solved, and the stable operation and safety of the device are improved.
Patent Information
- Application Number
- CN202311607192.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-11-28
- Publication Date
- 2025-05-30
AI Technical Summary
During the operation of the catalytic cracking device, it is difficult to judge the loss of catalysts in a timely and accurate manner, resulting in unstable operation and low safety of the device.
By quantifying the particle size distribution statistics of the balancer and regenerated flue gas in the catalytic cracking device regeneration system, the running loss position and reason of the catalyst are determined based on the particle size distribution and dust concentration of the catalyst.
The long-term and stable operation of the catalytic cracking device is achieved, the safety and industrial production value are improved, and the impact of catalyst losses on the operation of the device is reduced.
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Figure CN120064033A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of petroleum processing, and particularly to a method for identifying catalyst loss in the regeneration system of a fluid catalytic cracking unit. Background Art
[0002] According to incomplete statistics, there are more than 160 domestic fluid catalytic cracking (pyrolysis) units in operation, with a total processing capacity exceeding 240 million tons / year, and the annual consumption of catalytic cracking catalyst is more than 200,000 tons. Due to the characteristics of the catalytic cracking process and production requirements, the catalyst needs to continuously circulate in the riser reactor, settler, regenerator and catalyst regeneration system of the fluid catalytic cracking unit for fluidization, separation, stripping, regeneration, etc. Due to the objective existence of factors such as equipment separation accuracy and natural wear of the catalyst, there is a natural loss ratio of the catalyst. However, in the production operation of many fluid catalytic cracking units, the catalyst loss is significantly more than the normal loss amount (the normal loss amount is usually about 0.2 kg of catalyst / t of feedstock oil). However, because there is no effective monitoring method and characterization method to judge the catalyst loss path, finding the loss path of FCC catalyst in the unit is a major problem in the industry.
[0003] During the operation of a fluid catalytic cracking unit, catalyst loss is an inevitable and long-existing problem, which seriously affects the safe and stable long-term operation of the unit. However, there are many factors causing catalyst loss, involving catalyst properties, equipment design and operating load, equipment installation volume, feedstock oil properties, changes in unit operating conditions, equipment operation fatigue, failures and damages, etc. Identifying the cause and location of catalyst loss usually depends on the operation and production management experience of technicians, and it is difficult to quantitatively identify and accurately judge the catalyst loss location and specific reasons, etc.
[0004] From the perspective of the catalyst operation path of a fluid catalytic cracking unit, the catalyst loss lines of the fluid catalytic cracking unit are mainly two main lines: the riser reactor - settler reaction oil and gas line and the regenerator - cyclone - regenerated flue gas line. If the catalyst loss amount in the regenerator - cyclone - regenerated flue gas line is greater than the normal production consumption amount, or the dust content index in the discharged regenerated flue gas exceeds the process control experience value, it is easy to cause the overloading operation of the cyclone separators at all levels of the fluid catalytic cracking unit, resulting in scaling and blockage of the dust discharge pipes of the cyclone separators, or reduction and even failure of the cyclone efficiency; furthermore, it may cause problems such as an increase in the vibration value of the key equipment, the flue gas turbine, in the energy recovery unit of the fluid catalytic cracking unit, scaling of key parts such as blades, etc., leading to failures such as damage to the flue gas turbine, and even major production operation and safety accidents such as "runaway" of the flue gas turbine. Summary of the Invention
[0005] The object of the present invention is to overcome the problems in the prior art that during the operation of a catalytic cracking unit, the position of catalyst loss cannot be judged in a timely and accurate manner, resulting in the inability of the catalytic cracking unit to operate stably for a long time and low safety. A method for identifying catalyst loss in the regeneration system of a catalytic cracking unit is provided. This method can quantify the particle size distribution or concentration of the medium to be detected in combination with the characteristics of each link in the whole process of catalytic cracking, so as to facilitate the judgment of the position of catalyst loss, realize the long-term stable operation of the catalytic cracking unit, and improve safety and industrial production value.
[0006] To achieve the above object, the present invention provides a method for identifying catalyst loss in the regeneration system of a catalytic cracking unit. The method is carried out during the operation of the regeneration system of the catalytic cracking unit. The regeneration system of the catalytic cracking unit includes a regenerator, a three-stage cyclone separator, a four-stage cyclone separator, and a three-rotation fine powder sampler connected by pipelines; a balanced catalyst is placed in the regenerator, and the regenerator is used to regenerate the flue gas from the catalytic cracking unit to obtain regenerated flue gas; the three-stage cyclone separator is used to separate the regenerated flue gas to obtain first fine powder catalyst, first regenerated flue gas containing second fine powder catalyst and dust, and second regenerated flue gas containing dust; the four-stage cyclone separator is used to remove gas from the first regenerated flue gas containing second fine powder catalyst and dust to obtain second fine powder catalyst and first regenerated flue gas containing dust; the three-rotation fine powder sampler is used for discharging the mixture of the first fine powder catalyst and the second fine powder catalyst.
[0007] Wherein, the method includes the following steps:
[0008] (1) Quantitatively statistically analyze the particle size distribution of the balanced catalyst in the regenerator, measure the particle size distribution of the balanced catalyst in the ranges of 0-5μm, 0-10μm, 0-20μm, 0-30μm, 0-40μm, 0-60μm, 0-80μm, 0-149μm, and greater than 149μm, and then judge the position of catalyst loss according to the particle size distribution of the balanced catalyst.
[0009] (2) Quantitatively statistically analyze the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst at the three-rotation fine powder sampler, measure the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst in the ranges of 0-5μm, 0-10μm, 0-20μm, 0-30μm, 0-40μm, 0-60μm, 0-80μm, and greater than 80μm, and then judge the position of catalyst loss according to the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst.
[0010] (3) Quantify and count the particle size distribution of the dust in the second regeneration flue gas containing dust, analyze the content of dust <10 μm in the second regeneration flue gas containing dust, and then determine the location of catalyst damage based on the content of dust <10 μm in the second regeneration flue gas containing dust.
[0011] The method provided by the present invention quantifies the particle size distribution or concentration data according to the characteristics of each link in the whole process of catalytic cracking and the particle size distribution or concentration of the medium to be detected, so as to facilitate the determination of the damage position of the medium to be detected, realize the long-term stable operation of the catalytic cracking device, and improve the safety and industrial production value.
[0012] The method provided by the present invention regularly (or temporarily) analyzes the particle size distribution of the balance agent of the fluidized catalytic cracking unit, regularly (or temporarily) or online monitors and analyzes the dust concentration and particle size distribution in the regeneration flue gas, quantifies the data, forms a large database on the dust concentration and particle size distribution of the balance agent and regeneration flue gas during the operation of the catalytic cracking unit, comprehensively analyzes the data characteristics, and quantitatively determines the location of catalyst loss in the regeneration system of the fluidized catalytic cracking unit, thereby providing technical support for the safe and stable operation of the catalytic cracking unit.
[0013] The method provided by the present invention can identify the catalyst damage of the catalytic cracking unit and make targeted adjustments to the production operation of the unit according to the different damage locations and damage degrees of the catalyst, thereby reducing or eliminating the impact of the catalyst damage on the operation of the unit. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a schematic diagram of the regeneration system of the catalytic cracking unit provided by the present invention.
[0015] Description of Reference Numerals
[0016] 1-Three-stage cyclone separator 2-Four-stage cyclone separator
[0017] 3-Fourth-stage cyclone separator silo 4-Catalyst storage tank
[0018] 5- Flue gas turbine 6- Flue gas sampling port at the inlet of the third-stage cyclone separator
[0019] 7-Three-stage cyclone separator outlet flue gas sampling port 8-Three-cyclone fine powder sampling port DETAILED DESCRIPTION
[0020] The endpoints and any values within the ranges disclosed herein are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.
[0021] In the present invention, it should be noted that the absence of abnormal attrition means that there is no attrition in the regenerator or there is slight attrition in the equilibrium catalyst in the regenerator.
[0022] In the present invention, abnormal attrition refers to the catalyst attrition rate exceeding the designed catalyst recovery efficiency value of the regenerator cyclone separator (such as the attrition rate > 0.001%, that is, the recovery efficiency < 99.99%).
[0023] In the present invention, normal attrition refers to the catalyst attrition rate within the designed attrition rate range of the regenerator cyclone separator (such as the attrition rate ≤ 0.001%, that is, the recovery efficiency ≥ 99.99%).
[0024] In the present invention, it should be noted that the equilibrium catalyst, the first fine powder catalyst, the second fine powder catalyst, and the dust in the first regenerated flue gas and the second regenerated flue gas all belong to the catalysts conventionally defined in the art. In the present invention, by measuring the particle size distributions of the equilibrium catalyst, the first fine powder catalyst, and the second fine powder catalyst, and the dust concentration in the second regenerated flue gas, the catalyst attrition situation in the regenerator and the catalyst attrition position in the regenerator system of the fluid catalytic cracking unit are reflected.
[0025] The present invention provides a method for identifying catalyst loss in the regenerator system of a fluid catalytic cracking unit. The method is carried out during Figure 1 the operation of the regenerator system of the fluid catalytic cracking unit shown. The regenerator system of the fluid catalytic cracking unit includes a regenerator, a three-stage cyclone separator 1, a four-stage cyclone separator 2, and a three-cyclone fine powder sampler 8 connected by pipelines. An equilibrium catalyst is placed in the regenerator, and the regenerator is used to regenerate the flue gas from the fluid catalytic cracking unit to obtain regenerated flue gas. The three-stage cyclone separator 1 is used to separate the regenerated flue gas to obtain the first fine powder catalyst, the first regenerated flue gas containing the second fine powder catalyst and dust, and the second regenerated flue gas containing dust. The four-stage cyclone separator 2 is used to remove gas from the first regenerated flue gas containing the second fine powder catalyst and dust to obtain the second fine powder catalyst and the first regenerated flue gas containing dust. The three-cyclone fine powder sampler 8 is used to discharge the mixture of the first fine powder catalyst and the second fine powder catalyst.
[0026] Among them, the method includes the following steps:
[0027] (1) Quantitatively statistically analyze the particle size distribution of the equilibrium catalyst in the regenerator, and measure the particle size distribution of the equilibrium catalyst in the ranges of 0 - 5μm, 0 - 10μm, 0 - 20μm, 0 - 30μm, 0 - 40μm, 0 - 60μm, 0 - 80μm, 0 - 149μm, and greater than 149μm. Then, based on the particle size distribution of the equilibrium catalyst, determine the location of catalyst loss;
[0028] (2) Quantitatively statistically analyze the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst at the sampling port 8 of the three - stage cyclone fine powder collector, and measure the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst in the ranges of 0 - 5μm, 0 - 10μm, 0 - 20μm, 0 - 30μm, 0 - 40μm, 0 - 60μm, 0 - 80μm, and greater than 80μm. Then, based on the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst, determine the location of catalyst loss;
[0029] (3) Quantitatively statistically analyze the particle size distribution of the dust in the second regenerated flue gas containing dust, analyze the content of dust with a particle size less than 10μm in the second regenerated flue gas containing dust, and then based on the content of dust with a particle size less than 10μm in the second regenerated flue gas containing dust, determine the location of catalyst loss.
[0030] The method provided by the present invention quantifies the particle size distribution or concentration data according to the characteristics of each link in the entire catalytic cracking process and in combination with the particle size distribution or concentration of the medium to be detected, which is convenient for determining the location of loss of the medium to be detected, realizing the long - term stable operation of the catalytic cracking unit, and improving safety and industrial production value.
[0031] The method provided by the present invention regularly (or temporarily) analyzes the particle size distribution of the equilibrium catalyst in the fluid catalytic cracking unit, regularly (or temporarily) or online monitors and analyzes the dust concentration and particle size distribution in the regenerated flue gas, quantifies the data, forms a large database on the particle size distribution and dust concentration of the equilibrium catalyst and regenerated flue gas during the operation of the catalytic cracking unit, comprehensively analyzes the data characteristics, and quantitatively determines the location of catalyst loss in the regeneration system of the fluid catalytic cracking unit, providing technical support for the safe and stable operation of the catalytic cracking unit.
[0032] The method provided by the present invention provides data support for identifying catalyst loss in the regeneration system of the fluid catalytic cracking unit by determining the types of materials, analysis items, and analysis means required for analyzing catalyst loss.
[0033] After identifying the catalyst loss situation of the catalytic cracking unit by the method provided by the present invention, the production operation of the unit can be adjusted specifically according to different catalyst loss locations and loss degrees, reducing or eliminating the impact of catalyst loss on the unit operation.
[0034] In the present invention, the particle size distribution of the equilibrium catalyst in the regenerator is analyzed regularly or temporarily by using a reliable catalyst particle size distribution analyzer, and then the catalyst loss in the regenerator is analyzed according to the particle size distribution of the equilibrium catalyst. Preferably, in step (1), when the content of the equilibrium catalyst with a particle size of 0 - 20 μm is 0.2 - 1.5 vol% and when the content of the equilibrium catalyst with a particle size of 0 - 40 μm is 15 - 24 vol%, it is determined that there is no abnormal catalyst loss in the regenerator. In the present invention, preferably, a primary cyclone separator and a secondary cyclone separator (not shown in the figure) are provided in the regenerator. When the content of the particle size distribution of the equilibrium catalyst in the regenerator is within the above range, it can be determined that the separation effects of the primary cyclone separator and the secondary cyclone separator in the regenerator are good, and there is no abnormal catalyst loss in the regenerator.
[0035] In the present invention, the particle size distribution of the equilibrium catalyst in the regenerator is analyzed by using a reliable catalyst particle size distribution analyzer, and then the catalyst loss in the regenerator is analyzed according to the particle size distribution of the equilibrium catalyst. According to a preferred embodiment of the present invention, in step (1), when the content of the equilibrium catalyst with a particle size of 0 - 20 μm is less than 0.2 vol% and when the content of the equilibrium catalyst with a particle size of 0 - 40 μm is less than 15 vol%, it is determined that there is abnormal catalyst loss in the regenerator. When the content of the particle size distribution of the equilibrium catalyst in the regenerator is within the above range, it is determined that the separation effects of the primary cyclone separator and the secondary cyclone separator in the regenerator are poor, resulting in a large amount of abnormal catalyst loss in the regenerator. Abnormal catalyst loss occurs at the positions of the primary cyclone separator and the secondary cyclone separator in the regenerator. Technicians can make targeted adjustments to the production operation of the device according to the degree of catalyst loss to reduce or eliminate the impact of catalyst loss on the operation of the device.
[0036] According to another preferred embodiment of the present invention, in step (1), when the content of the equilibrium catalyst with a particle size of 0 - 20 μm is greater than 1.5 vol% and when the content of the equilibrium catalyst with a particle size of 0 - 40 μm is less than 15 vol%, it is determined that there is abnormal catalyst loss in the regenerator. When the content of the particle size distribution of the equilibrium catalyst in the regenerator is within the above range, it is determined that the separation effects of the primary cyclone separator and the secondary cyclone separator in the regenerator are poor, resulting in a large amount of abnormal catalyst loss in the regenerator. Abnormal catalyst loss occurs at the positions of the primary cyclone separator and the secondary cyclone separator in the regenerator. Technicians can make targeted adjustments to the production operation of the device according to the degree of catalyst loss to reduce or eliminate the impact of catalyst loss on the operation of the device.
[0037] In the present invention, the average particle size of the equilibrium catalyst is statistically calculated according to the particle size distribution in the regenerator, and then the catalyst loss in the regenerator is judged according to the average particle size of the equilibrium catalyst. Preferably, in step (1), when the average particle size of the equilibrium catalyst is 60 - 65 μm, it is determined that there is no abnormal catalyst loss in the regenerator.
[0038] In the present invention, the average particle size of the equilibrium catalyst is statistically calculated according to the particle size distribution in the regenerator, and then the elutriation situation of the equilibrium catalyst in the regenerator is judged based on the average particle size. Preferably, in step (1), when the average particle size of the equilibrium catalyst is greater than 65 μm, it is judged that there is abnormal elutriation of the catalyst in the regenerator.
[0039] In the present invention, the average particle size is used as one of the indicators for judging the elutriation of the equilibrium catalyst. The larger the average particle size of the equilibrium catalyst, the greater the elutriation ratio of the catalyst in the regenerator, indicating abnormal elutriation. Similarly, it also indicates that the separation effects of the primary cyclone separator and the secondary cyclone separator in the regenerator are not good. Technicians can make targeted adjustments to the production operation of the device according to the catalyst elutriation degree to reduce or eliminate the influence of catalyst elutriation on the operation of the device.
[0040] In the present invention, preferably, the regeneration system of the fluid catalytic cracking unit further includes a four-stage cyclone separator silo 3, a catalyst storage tank 4, and a flue gas sampling port 6 at the inlet of the three-stage cyclone separator. The four-stage cyclone separator silo 3 is used for temporarily storing the mixture of the first fine powder catalyst and the second fine powder catalyst. The catalyst storage tank 4 is used for storing the mixture of the first fine powder catalyst and the second fine powder catalyst. The flue gas sampling port 6 at the inlet of the three-stage cyclone separator is used for introducing the regenerated flue gas.
[0041] In the present invention, the regenerated flue gas enters the third-stage cyclone separator 1 and the fourth-stage cyclone separator 2 in sequence through the flue gas sampling port 6 at the inlet of the three-stage cyclone separator for solid-gas separation. The first fine powder catalyst in the regenerated flue gas is separated by the third-stage cyclone separator 1, and the first regenerated flue gas containing the second fine powder catalyst and dust, as well as the second regenerated flue gas containing dust are obtained. The first regenerated flue gas is separated by the fourth-stage cyclone separator 2 to obtain the second fine powder catalyst and the first regenerated flue gas containing dust. The mixture after mixing the first fine powder catalyst and the second fine powder catalyst is stored in the catalyst storage tank 4, and the mixture of the first fine powder catalyst and the second fine powder catalyst is taken out from the three-cyclone fine powder sampling port regularly or temporarily. Then, a reliable catalyst particle size distribution analyzer is used to analyze the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst, and then the catalyst loss situation in the regenerator is analyzed according to the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst. Preferably, in step (2), when the content of particles with a particle size greater than 40 μm in the mixture of the first fine powder catalyst and the second fine powder catalyst is not less than 0.5% by volume, it is determined that there is abnormal loss in the regenerator; preferably, in step (2), when the content of particles with a particle size greater than 40 μm in the mixture of the first fine powder catalyst and the second fine powder catalyst is 0.5 - 100% by volume, it is determined that there is abnormal loss of the catalyst in the regenerator. In the present invention, by analyzing the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst, it is further reflected whether there is abnormal loss in the regenerator. When it is determined that there is abnormal loss of the catalyst in the regenerator, technicians can supplement the catalyst adaptively according to its specific loss degree to ensure the stable operation of the device.
[0042] In the present invention, preferably, in step (2), when the content of particles with a particle size of 0 - 40 μm in the mixture of the first fine powder catalyst and the second fine powder catalyst is 99.5 - 100% by volume, it is determined that there is no abnormal loss of the catalyst in the regenerator.
[0043] In the present invention, the average particle size of the first fine powder catalyst and the second fine powder catalyst is statistically calculated according to the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst, and then the catalyst loss situation in the regenerator is judged according to the average particle size. Preferably, in step (2), when the average particle size of the mixture of the first fine powder catalyst and the second fine powder catalyst is ≤20 μm, it is determined that there is no abnormal loss of the catalyst in the regenerator.
[0044] In the present invention, preferably, in step (2), when the average particle size of the mixture of the first fine powder catalyst and the second fine powder catalyst >20 μm, it is determined that there is abnormal loss of the catalyst in the regenerator.
[0045] In the present invention, preferably, the catalytic cracking unit regeneration system further comprises a flue gas turbine 5, and the flue gas turbine 5 is used to recover the energy of the second regeneration flue gas containing dust.
[0046] In the present invention, the regenerated flue gas is separated by a three-stage cyclone separator to obtain a second regenerated flue gas containing dust. The second regenerated flue gas is expanded by a flue gas turbine 5 to recover the energy in the flue gas, and then enters a subsequent flue gas desulfurization and other flue gas purification device for treatment and meets the emission standards. The present invention determines whether the catalyst in the regenerator has abnormal running and damage by regularly or temporarily analyzing the particle size distribution and content of the dust in the second regenerated flue gas. Preferably, in step (3), when the content of dust with a particle size of <10μm in the second regenerated flue gas containing dust is ≥97% by volume, it is determined that the catalyst in the regenerator has not abnormally run and damage.
[0047] In the present invention, preferably, in step (3), when the content of dust with a particle size of <10 μm in the second regeneration flue gas containing dust is <97% by volume, it is determined that the catalyst in the regenerator has abnormal wear.
[0048] In the present invention, the second regeneration flue gas containing dust is separated by a three-stage cyclone separator. By analyzing the dust distribution and content of the second regeneration flue gas containing dust, the separation effect of the three-stage cyclone separator is judged, and the catalyst wear in the regenerator is reflected.
[0049] In the present invention, preferably, the catalytic cracking regeneration device further comprises a three-stage cyclone separator outlet flue gas sampling port 7, and the three-stage cyclone separator outlet flue gas sampling port 7 is used to discharge the second regeneration flue gas containing dust. The present invention does not particularly limit the sampling position of the second regeneration flue gas, as long as the second regeneration flue gas can be extracted, for example, the second regeneration flue gas can be collected at any position (preferably a horizontal section) after the second regeneration flue gas is discharged from the three-stage cyclone separator 1 and before it enters the flue gas turbine 5. More specifically, the sampling can be performed at the three-stage cyclone separator outlet flue gas sampling port 7, or on the pipeline of the three-stage cyclone separator outlet flue gas sampling port 7.
[0050] The present invention will be described in detail below through examples.
[0051] The properties of the fresh catalysts used in the following examples are shown in Table 1.
[0052] Example
[0053] The method of this embodiment is as follows Figure 1During the operation of the shown system, after the fresh catalyst is used in catalytic cracking, it enters the regenerator of the catalytic cracking regeneration system to obtain the equilibrium catalyst; in the presence of the equilibrium catalyst, the flue gas enters the regenerator for regeneration to obtain the regenerated flue gas. The regenerated flue gas enters the third-stage cyclone separator 1 through the inlet flue gas sampling port 6 of the third-stage cyclone separator for separation, obtaining the first fine powder catalyst, the first regenerated flue gas containing the second fine powder catalyst and dust, and the second regenerated flue gas containing dust. The second regenerated flue gas containing dust enters the gas turbine 5 through the outlet flue gas sampling port 7 of the third-stage cyclone separator and is recycled to the subsequent process; the first regenerated flue gas containing the second fine powder catalyst and dust enters the fourth-stage cyclone separator 2 for gas removal, obtaining the second fine powder catalyst and the first regenerated flue gas containing dust. The first fine powder catalyst and the second fine powder catalyst enter the bin 3 of the fourth-stage cyclone separator for temporary storage, and then enter the catalyst storage tank 4 for storage. Subsequently, a mixture of the first fine powder catalyst and the second fine powder catalyst is periodically or temporarily sampled from the sampling port 8 of the three-cyclone fine powder agent for sampling and analysis.
[0054] (1) The particle size distributions of the equilibrium catalysts in the regenerators of the three sets of catalytic cracking units A, B, and C were respectively statistically analyzed by the method of the present invention. The results are shown in Table 2. Specifically,
[0055] The content of 0 - 20 μm in the equilibrium catalyst of Unit A is 0% by volume, the content of 0 - 40 μm is 5.04% by volume, and the average particle size is 77.09 μm. It can be judged that the effects of the first-stage cyclone separator and the second-stage cyclone separator in the regenerator of this unit are not good, resulting in a large abnormal loss of the equilibrium catalyst in the regenerator;
[0056] The content of 0 - 20 μm in the equilibrium catalyst of Unit B is 0.31% by volume, the content of 0 - 40 μm is 15.19% by volume, and the average particle size is 70.12 μm. It can be judged that the effects of the first-stage cyclone separator and the second-stage cyclone separator in the regenerator of this unit are better than those of Unit A, but there is still a certain degree of abnormal loss of the equilibrium catalyst in the regenerator;
[0057] The content of 0 - 20 μm in the equilibrium catalyst of Unit C is 0.93% by volume, the content of 0 - 40 μm is 21.82% by volume, and the average particle size is 60.14 μm. It can be judged that the effects of the first-stage cyclone separator and the second-stage cyclone separator in the regenerator of this unit are good, and the abnormal loss of the equilibrium catalyst in the regenerator is very small.
[0058] (2) The particle size distributions of the mixtures of the first fine powder catalyst and the second fine powder catalyst in the three sets of catalytic cracking units A, B, and C were respectively statistically analyzed by the method of the present invention. The results are shown in Table 3. Specifically,
[0059] In the mixture of the first fine powder catalyst and the second fine powder catalyst of Unit A, the content of particles with a size of 0 - 5μm is 4.1% by volume, the content of particles with a size of 0 - 10μm is 6.40% by volume, the content of particles with a size of 0 - 20μm is 23.80% by volume, the content of particles with a size of 0 - 30μm is 59.30% by volume, the content of particles with a size of 0 - 40μm is 81.30% by volume, the content of particles with a size of 0 - 80μm is 100.00%, and the average particle size is 27.90μm. It can be judged that the performance of the primary cyclone separator and the secondary cyclone separator in the regenerator of this unit is not good. Part of the equilibrium catalyst with a size of ≥40μm in the regenerator is lost with the regenerated flue gas and recovered in the tertiary cyclone separator, which verifies the reason for the low content (by volume) of 0 - 40μm in the equilibrium catalyst particle size distribution of Unit A listed in Table 2;
[0060] In the mixture of the first fine powder catalyst and the second fine powder catalyst of Unit B, the content of particles with a size of 0 - 5μm is 11.20% by volume, the content of particles with a size of 0 - 10μm is 27.40% by volume, the content of particles with a size of 0 - 20μm is 68.10% by volume, the content of particles with a size of 0 - 30μm is 87.90% by volume, the content of particles with a size of 0 - 40μm is 94.30% by volume, the content of particles with a size of 0 - 80μm is 98.30%, and the average particle size is 28.60μm. It can be judged that the performance of the primary cyclone separator and the secondary cyclone separator in the regenerator of this unit is also poor. Part of the particles with a size of ≥40μm in the regenerator is lost with the regenerated flue gas and recovered in the tertiary cyclone separator, which verifies the reason for the low content (by volume) of 0 - 40μm in the equilibrium catalyst particle size distribution of Unit B listed in Table 2;
[0061] In the mixture of the first fine powder catalyst and the second fine powder catalyst of Unit C, the content of particles with a size of 0 - 5μm is 3.67% by volume, the content of particles with a size of 0 - 10μm is 8.29% by volume, the content of particles with a size of 0 - 20μm is 55.05% by volume, the content of particles with a size of 0 - 30μm is 88.90% by volume, the content of particles with a size of 0 - 40μm is 100.00% by volume, the content of particles with a size of 0 - 80μm is 100.00%, and the average particle size is 16.07μm. It can be judged that the performance of the primary cyclone separator and the secondary cyclone separator in the regenerator of this unit is very good. Part of the catalyst with a size of ≥40μm in the regenerator is recovered in the regenerator, and the catalyst recovered by the tertiary cyclone separator is all <40μm.
[0062] (3) The particle size distribution of the dust in the second regenerated flue gas containing dust at the inlet of the gas turbine 5 of the catalytic cracking units A and B was statistically analyzed by the method of the present invention respectively, and the results are shown in Table 4. Specifically,
[0063] In the second regenerated flue gas containing dust at the inlet of the gas turbine 7 of Unit A, the average content of dust with a size of <10μm is 94.39% by volume. In the second regenerated flue gas containing dust at the inlet of the gas turbine 7 of Unit B, the average content of dust with a size of <10μm is 88.27% by volume. It can be judged that the separation effect of the tertiary cyclone separator of Unit A is better than that of the tertiary cyclone separator of Unit B.
[0064] Table 1
[0065]
[0066] Table 2
[0067] Device A Device B Device C 0 - 20 μm (volume fraction) 0 0.31 0.93 0 - 40 μm (volume fraction) 5.04 15.19 21.82 0 - 80 μm (volume fraction) 56.15 64.72 61.16 ≥80 μm (volume fraction) 43.85 35.28 38.84 Average particle size μm 77.09 70.12 60.14
[0068] Table 3
[0069] Item Device A Device B Device C 0 - 5 μm (volume fraction) 4.10 11.20 3.67 0 - 10 μm (volume fraction) 6.40 27.40 8.29 0 - 20 μm (volume fraction) 23.80 68.10 55.05 0 - 30 μm (volume fraction) 59.30 87.90 88.90 0 - 40 μm (volume fraction) 81.30 94.30 99.08 0 - 80 μm (volume fraction) 100.00 98.30 100.00 Average particle size μm 27.90 16.20 19.08
[0070] Table 4
[0071] Sample Particle size of dust in device A < 10μm, v% Dust particle size of device B < 10μm, v% 1 92.50 83.77 2 92.19 90.78 3 95.75 91.14 4 95.29 82.18 5 94.98 94.09 6 95.40 92.17 7 94.60 83.77 Average 94.39 88.27
[0072] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.
Claims
1. A method for identifying catalyst loss in the regeneration system of a fluid catalytic cracking unit. This method is carried out during the operation of the regeneration system of the fluid catalytic cracking unit. The regeneration system of the fluid catalytic cracking unit includes a regenerator, a third-stage cyclone separator (1), a fourth-stage cyclone separator (2), and a three-cyclone fine powder sampling port (8) connected by pipelines. A balanced catalyst is placed in the regenerator, and the regenerator is used to regenerate the flue gas from the fluid catalytic cracking unit to obtain regenerated flue gas. The third-stage cyclone separator (1) is used to separate the regenerated flue gas to obtain first fine powder catalyst, first regenerated flue gas containing second fine powder catalyst and dust, and second regenerated flue gas containing dust. The fourth-stage cyclone separator (2) is used to remove gas from the first regenerated flue gas containing second fine powder catalyst and dust to obtain second fine powder catalyst and first regenerated flue gas containing dust. The three-cyclone fine powder sampling port (8) is used to discharge the mixture of the first fine powder catalyst and the second fine powder catalyst. Wherein, The method includes the following steps: (1) Quantitatively statistically analyze the particle size distribution of the balanced catalyst in the regenerator, measure the particle size distribution of the balanced catalyst in the ranges of 0 - 5μm, 0 - 10μm, 0 - 20μm, 0 - 30μm, 0 - 40μm, 0 - 60μm, 0 - 80μm, 0 - 149μm, and greater than 149μm, and then judge the catalyst loss position according to the particle size distribution of the balanced catalyst. (2) Quantitatively statistically analyze the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst at the three-cyclone fine powder sampling port (8), measure the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst in the ranges of 0 - 5μm, 0 - 10μm, 0 - 20μm, 0 - 30μm, 0 - 40μm, 0 - 60μm, 0 - 80μm, and greater than 80μm, and then judge the catalyst loss position according to the particle size distribution of the mixture of the first fine powder catalyst and the second fine powder catalyst. (3) Quantitatively statistically analyze the particle size distribution of the dust in the second regenerated flue gas containing dust, analyze the content of dust with a particle size less than 10μm in the second regenerated flue gas containing dust, and then judge the catalyst loss position according to the content of dust with a particle size less than 10μm in the second regenerated flue gas containing dust.
2. The method according to claim 1, Wherein, In step (1), when the content of the balanced catalyst with a particle size in the range of 0 - 20μm is 0.2 - 1.5% by volume and when the content of the balanced catalyst with a particle size in the range of 0 - 40μm is 15 - 24% by volume, it is judged that there is no abnormal catalyst loss in the regenerator.
3. The method according to claim 1 or 2, Wherein, In step (1), when the content of the balanced catalyst with a particle size in the range of 0 - 20μm is less than 0.2% by volume and when the content of the balanced catalyst with a particle size in the range of 0 - 40μm is less than 15% by volume, it is judged that there is abnormal catalyst loss in the regenerator.
4. The method according to claim 1 or 2, Wherein, In step (1), when the content of the equilibrium catalyst with a particle size of 0 - 20 μm is greater than 1.5% by volume and when the content of the equilibrium catalyst with a particle size of 0 - 40 μm is less than 15% by volume, it is determined that there is abnormal catalyst loss in the regenerator.
5. The method according to claim 1 or 2, wherein, in step (1), when the average particle size of the equilibrium catalyst is 60 - 65 μm, it is determined that there is no abnormal catalyst loss in the regenerator.
6. The method according to claim 5, wherein, in step (1), when the average particle size of the equilibrium catalyst is greater than 65 μm, it is determined that there is abnormal catalyst loss in the regenerator.
7. The method according to claim 1 or 2, wherein, in step (2), when the content of the particle size greater than 40 μm in the mixture of the first fine powder catalyst and the second fine powder catalyst is not less than 0.5% by volume, it is determined that there is abnormal catalyst loss in the regenerator.
8. The method according to claim 7, wherein, in step (2), when the content of the particle size greater than 40 μm in the mixture of the first fine powder catalyst and the second fine powder catalyst is 0.5 - 100% by volume, it is determined that there is abnormal catalyst loss in the regenerator.
9. The method according to claim 1 or 2, wherein, in step (2), when the content of the particle size of 0 - 40 μm in the mixture of the first fine powder catalyst and the second fine powder catalyst is 99.5 - 100% by volume, it is determined that there is no abnormal catalyst loss in the regenerator; Preferably, in step (2), when the average particle size of the mixture of the first fine powder catalyst and the second fine powder catalyst is ≤ 20 μm, it is determined that there is no abnormal catalyst loss in the regenerator.
10. The method according to claim 1 or 2, wherein, in step (3), when the content of the dust with a particle size < 10 μm in the second regenerated flue gas containing dust is ≥ 97% by volume, it is determined that there is no abnormal catalyst loss in the regenerator.