Catalyst unloading system and method for catalytic cracking unit

Abstract

This invention provides a catalyst unloading system and method for a catalytic cracking unit. The system includes a catalyst storage tank, an air extractor, and a dust collection device. The air extractor is located at the top of the catalyst storage tank, and the outlet on the upper side wall of the catalyst storage tank is connected to the dust collection device. The air extractor is a steam air extractor, including a sintered filter and a steam injector. The lower end of the steam injector is connected to the upper end of the sintered filter. The sintered filter is located at the top of the catalyst storage tank, and its lower end is located inside the catalyst storage tank. This invention changes the current situation where the catalyst at the bottom of the regenerator needs to be manually bagged after the catalytic cracking unit is shut down. It also combines catalyst transfer with dust removal, completely changing the operating environment for unloading catalyst during shutdown of the catalytic cracking unit, improving unloading efficiency, and avoiding moisture and contamination during the bagging and transfer of the unloaded catalyst.

Description

Technical Field

[0001] The invention relates to the field of petrochemical industry, and in particular to a catalyst unloading system and method for a catalytic cracking unit. Background Art

[0002] At present, the catalytic cracking unit uses powdered catalytic cracking catalyst. During the shutdown and maintenance period, the catalyst in the regenerator must be transferred out and used as a start-up balance agent.

[0003] The regenerator shutdown and catalyst transfer operation in this catalytic cracking unit relies on the unit's own catalyst unloading system. Since the catalyst unloading port of the catalyst unloading system cannot be set at the lowest point of the regenerator, the catalyst below the catalyst unloading port in the regenerator cannot be transferred in the existing catalyst unloading system. In the actual operation process, workers need to manually bag the catalyst at the bottom of the regenerator and transfer it out of the regenerator. This operation method has high labor intensity for workers, and the environmental dust pollution during the catalyst loading and transfer process is large. In addition, the bagged catalyst is easily damp and contaminated during the catalyst loading and transfer process, and cannot be reused as a balance agent. Summary of the invention

[0004] In order to solve the problems that the existing operating method has high labor intensity for workers, large environmental dust pollution during the loading and transfer process, and the bagged catalyst is easily affected by moisture and contaminated during the loading and transfer process, and cannot be reused as a balance agent, the present invention provides a catalyst unloading system and method for a catalytic cracking unit. The present invention changes the current situation that the catalyst at the bottom of the regenerator needs to be manually bagged after the catalytic cracking unit is shut down, and at the same time combines the catalyst transfer with dust removal, completely changes the operating environment of the catalytic cracking unit shutdown unloading, improves the unloading efficiency, and avoids the situation that the catalyst is affected by moisture and contamination during the bagging and transfer process after unloading.

[0005] The technical solution adopted by the present invention is:

[0006] A catalyst unloading system for a catalytic cracking device comprises a catalyst storage tank, an evacuator and a dust collecting device, wherein the evacuator is arranged on the top of the catalyst storage tank, and an outlet on the upper side wall of the catalyst storage tank is connected to the dust collecting device.

[0007] The vacuum evacuator is a steam vacuum evacuator, which includes a sintered filter and a steam ejector. The lower end of the steam ejector is connected to the upper end of the sintered filter. The sintered filter is arranged on the top of the catalyst storage tank, and the lower end of the sintered filter is located in the catalyst storage tank.

[0008] The dust collecting device at least comprises a powder conveying pipeline and a dust collector, wherein the dust collector is connected to the outlet of the upper side wall of the catalyst storage tank through the powder conveying pipeline; both ends of the powder conveying pipeline are provided with cut-off valves.

[0009] The dust collector comprises a rubber hose and a filter. One end of the filter is connected to the rubber hose through a reducer, and the other end is connected to a powder conveying pipeline of the dust collecting device.

[0010] The filter is a Y-type filter.

[0011] The pore size of the filter screen in the Y-type filter does not exceed 3mm.

[0012] The catalyst storage tank has a cylindrical upper end and a conical lower end, and a catalyst discharge valve is arranged at the conical bottom.

[0013] A stamping valve is arranged on the side wall of the catalyst storage tank, and a safety valve, a material level measuring port and a pressure gauge are also arranged on the top of the catalyst storage tank.

[0014] A catalyst unloading method for a catalytic cracking unit, comprising the following specific steps: Step 1, closing a stamping valve on a catalyst storage tank;

[0015] Step 2: Vacuum, turn on the steam evacuator to evacuate, and confirm that the vacuum degree is below -0.15Mpa;

[0016] Step 3, turn on the dust collector and start working;

[0017] Step 4: After the operation is completed, turn off the steam evacuator, wait until the pressure returns to one atmosphere, and then turn off the dust collector to complete the operation.

[0018] In the above step 4, when closing the dust collector, first close the shut-off valve at the connection between the dust collector and the powder conveying pipeline, and then close the shut-off valve at the connection between the catalyst storage tank side wall outlet and the powder conveying pipeline.

[0019] The beneficial effects of the present invention are:

[0020] The present invention adds an evacuator and a dust collecting device, changes the operating environment of catalyst unloading during shutdown of a catalytic cracking unit, improves catalyst unloading efficiency, and avoids moisture and contamination during bagging and transfer of catalyst after catalyst unloading.

[0021] The following is a further description with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the structure of the present invention is shown in FIG.

[0023] In the figure, the reference numerals are: 1, catalyst storage tank; 101, stamping valve; 102, unloading valve; 103, safety valve; 104, material level measuring port; 2, vacuum pump; 201, sintering filter; 202, steam ejector; 3, powder conveying pipeline; 4, dust collector; 401, rubber hose; 402, filter; 403, reducer; 5, pressure gauge; 6, shut-off valve. DETAILED DESCRIPTION

[0024] Embodiment 1:

[0025] In order to solve the problems of high labor intensity of workers in the existing operation mode, large dust pollution in the environment during the loading and transfer process, and the bagged catalyst is easily damp and contaminated during the loading and transfer process, and cannot be reused as a balancing agent, the present invention provides a Figure 1 The catalyst unloading system and method of a catalytic cracking unit are shown. The present invention changes the operating environment of the catalytic cracking unit during shutdown and unloading, improves the unloading efficiency, and avoids moisture and contamination during bagging and transfer of the catalyst after unloading.

[0026] A catalyst unloading system for a catalytic cracking unit comprises a catalyst storage tank 1, an evacuator 2 and a dust collecting device, wherein the evacuator 2 is arranged on the top of the catalyst storage tank 1, and an outlet on the upper side wall of the catalyst storage tank 1 is connected to the dust collecting device.

[0027] In the present invention, the catalyst storage tank 1 is used to store the catalyst, the vacuum device 2 is used to form negative pressure, and the dust collecting device is used to remove dust. The present invention changes the current situation that the catalyst at the bottom of the regenerator needs to be manually bagged after the catalytic cracking unit is shut down. The present invention combines catalyst transfer with dust removal, completely changes the operating environment of catalyst unloading during shutdown of the catalytic cracking unit, improves catalyst unloading efficiency, and avoids moisture and contamination during bagging and transfer after catalyst unloading.

[0028] Embodiment 2:

[0029] Based on Example 1, in this embodiment, preferably, the evacuator 2 is a steam evacuator, including a sintered filter 201 and a steam injector 202, the lower end of the steam injector 202 is connected to the upper end of the sintered filter 201, the sintered filter 201 is arranged on the top of the catalyst storage tank 1, and the lower end of the sintered filter 201 is located in the catalyst storage tank 1.

[0030] Preferably, the dust collecting device at least comprises a powder conveying pipeline 3 and a dust collector 4, and the dust collector 4 is connected to the upper side wall outlet of the catalyst storage tank 1 through the powder conveying pipeline 3; both ends of the powder conveying pipeline 3 are provided with a shut-off valve 6.

[0031] In the present invention, the powder delivery pipeline 3 is made of Q345R, with a diameter of DN200, and the length of the pipeline can be determined according to actual conditions (generally greater than 10 meters), and there is no coating inside. Both ends of the powder delivery pipeline 3 are connected to the cut-off valve 6, and one of the cut-off valves 6 is connected to the filter 402 of the dust collector 4 through a flange.

[0032] Preferably, the dust collector 4 comprises a rubber hose 401 and a filter 402 , one end of the filter 402 is connected to the rubber hose 401 via a reducer 403 , and the other end is connected to the powder conveying pipeline 3 of the dust collecting device.

[0033] The reducer 403 solves the problem of different diameters when connecting pipes, and at the same time has the function of reducing vibration and noise, which can save pipe installation parts and save costs.

[0034] Preferably, the filter 402 is a Y-type filter.

[0035] Preferably, the pore size of the inner filter of the Y-type filter does not exceed 3 mm.

[0036] In the present invention, the rubber hose 401 is preferably a DN150 wear-resistant steel wire skeleton corrugated hose, one end of which has a flange, one end of the flange is connected to a concentric reducer DN200 to DN150, and the other end of the flange is connected to the filter 402. The filter 402 is preferably a DN200 flange Y-type filter with a filter mesh aperture of 3mm, which mainly filters broken linings and other debris. The length of the rubber hose 401 is determined according to actual use. The Y-type filter has the advantages of advanced structure, small resistance, and convenient sewage discharge.

[0037] Preferably, the catalyst storage tank 1 has a cylindrical upper end and a conical lower end, and a catalyst discharge valve 102 is provided at the conical bottom.

[0038] Preferably, a stamping valve 101 is provided on the side wall of the catalyst storage tank 1 , and a safety valve 103 , a material level measuring port 104 and a pressure gauge 5 are also provided on the top of the catalyst storage tank 1 .

[0039] like Figure 1 As shown, in the present invention, the catalyst storage tank 1 has a cylindrical structure at the top and a cone at the bottom. The catalyst storage tank 1 is provided with multiple ports on the top, including at least: an evacuation port, a material level measurement port, a pressure gauge port, and a safety valve port. A sintered filter 201 is provided at the connection between the catalyst storage tank 1 and the evacuation port. The evacuation port is connected to the steam ejector 202, a pressure gauge 5 is provided at the pressure gauge port, a safety valve 103 is connected to the safety valve port, and a double gate valve is installed at the material level measurement port 104. A stamping port is provided at the upper part of the side wall of the catalyst storage tank 1, and a stamping valve 101 is provided at the stamping port. A discharge port is provided at the bottom of the lower cone of the catalyst storage tank 1, and a discharge valve 102 is provided at the discharge port. The design temperature of the catalyst storage tank 1 is 220-450℃, and the design pressure is 0.78-1.0 MPa (abs). The material is Q345R. The preferred catalyst storage tank 1 has an inner diameter of φ6000mm, a wall thickness of 18mm, and a total height of 23000mm.

[0040] The present invention provides a catalyst unloading method for a catalytic cracking device, which specifically comprises the following steps: Step 1, closing the stamping valve 101 on the catalyst storage tank 1;

[0041] Step 2: Vacuuming: Open the steam evacuator 2 to evacuate and confirm that the vacuum degree is below -0.15Mpa;

[0042] Step 3, turn on the dust collector 4 and start working;

[0043] Step 4: After the operation is completed, close the steam evacuator 2, wait until the pressure returns to one atmosphere, and then close the dust collector 4 to complete the operation.

[0044] Preferably, in step 4, when closing the dust collector 4, first close the shut-off valve 6 at the connection between the dust collector 4 and the powder conveying pipeline 3, and then close the shut-off valve 6 at the connection between the side wall outlet of the catalyst storage tank 1 and the powder conveying pipeline 3.

[0045] The implementation process of the present invention is:

[0046] 1. Check whether there is pressure in the catalyst storage tank 1 through the pressure gauge 5. If there is pressure (the pressure will not exceed 0.5MPa on site), close the stamping valve 101.

[0047] 2. Vacuuming: Open the steam evacuator 2 to evacuate.

[0048] 3. Confirm that the vacuum degree is below -0.15MPa.

[0049] 4. Open the dust collector 4 and start working; when the operation is completed, the catalyst unloading is completed and closed

[0050] Steam evacuator, wait until the pressure returns to normal pressure (one atmosphere) and close the dust collector 4.

[0051] The working principle of the present invention is as follows: after the steam evacuator 2 is started, a negative pressure is formed in the catalyst storage tank 1, and the catalyst below the unloading port in the regenerator is sucked into the catalyst storage tank 1 through the powder conveying pipeline 3 and the dust collector 4, without manual bagging. At the same time, because the catalyst transfer process is a negative pressure operation, the catalyst dust will not be raised during the previous manual bagging. At the same time, the catalyst dust can reach the catalyst storage tank 1 through the integrator 4, avoiding the pollution that may occur during the bagging and transfer process, completely changing the operating environment of the catalytic cracking unit shutdown unloading, and improving the unloading efficiency.

[0052] The present invention can realize dust-free operation of catalyst unloading at the bottom of the regenerator after the catalytic device is shut down, can completely avoid the possibility of catalyst being dampened and contaminated during the catalyst unloading process, and can reduce the workload of catalyst unloading.

[0053] The above examples are merely illustrative of the present invention and do not constitute a limitation on the protection scope of the present invention. Any design that is the same or similar to the present invention belongs to the protection scope of the present invention. The device structure and method steps not described in detail in the present invention are all prior art and will not be further described in the present invention.

Claims

1. A catalyst unloading system for a catalytic cracking unit, characterized in that: The invention comprises a catalyst storage tank (1), an evacuator (2) and a dust collecting device, wherein the evacuator (2) is arranged at the top of the catalyst storage tank (1), and the outlet of the upper side wall of the catalyst storage tank (1) is connected to the dust collecting device; the evacuator (2) is a steam evacuator, comprising a sintered filter (201) and a steam ejector (202), the lower end of the steam ejector (202) is connected to the upper end of the sintered filter (201), the sintered filter (201) is arranged at the top of the catalyst storage tank (1), and the lower end of the sintered filter (201) is located in the catalyst storage tank (1); the dust collecting device comprises at least a powder conveying pipeline (3) and a dust collector (4), and the dust collector (4) is connected to the outlet of the upper side wall of the catalyst storage tank (1) via the powder conveying pipeline (3); and cut-off valves (6) are provided at both ends of the powder conveying pipeline (3).

2. The catalyst unloading system of a catalytic cracking unit according to claim 1, characterized in that: The dust collector (4) comprises a rubber hose (401) and a filter (402); one end of the filter (402) is connected to the rubber hose (401) via a reducer (403), and the other end is connected to a powder conveying pipeline (3) of the dust collecting device.

3. The catalyst unloading system of a catalytic cracking unit according to claim 2, characterized in that: The filter (402) is a Y-type filter.

4. The catalyst unloading system of a catalytic cracking unit according to claim 3, characterized in that: The pore size of the filter screen in the Y-type filter does not exceed 3mm.

5. The catalyst unloading system for a catalytic cracking unit according to claim 1, characterized in that: The catalyst storage tank (1) has a cylindrical upper end and a conical lower end, and a catalyst discharge valve (102) is provided at the conical bottom.

6. A catalyst unloading system for a catalytic cracking unit according to claim 1 or 5, characterized in that: A stamping valve (101) is provided on the side wall of the catalyst storage tank (1), and a safety valve (103), a material level measuring port (104) and a pressure gauge (5) are also provided on the top of the catalyst storage tank (1).

7. A catalyst unloading method for a catalytic cracking unit, characterized in that: The specific steps are as follows: Step 1, closing the stamping valve (101) on the catalyst storage tank (1); Step 2: Vacuuming: Open the steam evacuator (2) to evacuate the air and make sure the vacuum degree is below -0.15 MPa; Step 3, open the dust collector (4) to start working; Step 4: After the operation is completed, the steam evacuator (2) is closed, and the dust collector (4) is closed after the pressure returns to one atmosphere to complete the operation.

8. A catalyst unloading method for a catalytic cracking unit according to claim 7, characterized in that: In the above-mentioned step 4, when closing the dust collector (4), first close the shut-off valve (6) at the connection between the dust collector (4) and the powder conveying pipeline (3), and then close the shut-off valve (6) at the connection between the side wall outlet of the catalyst storage tank (1) and the powder conveying pipeline (3).

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