CN1336418A - Reforming catalyst regenerating process and apparatus with continuous two--section axial flow combined bed - Google Patents

Abstract

The invention belongs to the reforming and regeneration of petrochemical catalysts. The catalyst carbon deposit burning process is as follows: the deactivated catalyst enters the first zone and the regeneration gas flows downward to contact, and burns 60-8% of the carbon deposit; the first zone regenerates the flue gas Supplementary gas and quenching gas are mixed in the second zone to contact with the catalyst coming down from the first zone to burn the remaining carbon deposits. The catalyst distributor of the present invention is in the shape of a funnel, which is connected to the feeding channel. There are first and second sections of axial flow moving bed with conical screens below it, and the lower part of the axial flow moving bed of the second section is separated from the chlorination and oxidation zone. The unloading channel communicates with the chlorination oxidation zone. The bed temperature of the invention is evenly distributed along the radial direction, which is easy to control, the oxygen in the regeneration gas can be fully utilized, the flow rate of the regeneration gas can be reduced by nearly 40%, the inlet temperature of the regeneration gas can be reduced to 445°C, and the utilization rate of the equipment is high.

Description

Continuous two-stage axial flow combined bed regeneration process method and equipment for reforming catalyst

The invention belongs to the technical field of petrochemical industry, relates to catalyst reforming and regeneration, in particular to a process for burning off carbon on the surface of reforming catalysts, and relates to a continuous two-stage axial flow combined bed regeneration process and equipment for reforming catalysts.

Catalytic reforming is an important process for the production of high-octane gasoline, aromatics and cheap hydrogen. Reforming processing capacity is one of the important indicators to measure the advanced petrochemical technology. In areas with relatively developed technology, reforming processing capacity accounts for about 20% of crude oil processing volume, while in relatively less developed areas, reforming capacity can only account for 20% of crude oil processing volume. about 5%. With the development of the petrochemical industry, the demand for aromatics has increased greatly. At the same time, due to the increasing quality of gasoline due to environmental protection requirements, the demand for high-octane gasoline without lead has increased rapidly. Catalytic reforming will inevitably have greater development in the future. .

Continuous catalytic reforming has the characteristics of low operating pressure, small hydrogen-to-hydrocarbon ratio and continuous catalyst regeneration. Currently, there are two continuous reforming technologies, UOP in the United States and IFP in France. In the reforming process, the continuous catalyst regeneration technology is the key to continuous catalytic reforming. UOP and IFP have carried out several updates on the regeneration technology. So far, UOP has developed three generations of technology, and IFP has developed two generations of technology. The third-generation UOP continuous catalytic reforming technology is also called Cycle Max process, the reaction pressure is 0.35MPa, the regeneration pressure is 0.25Mpa, and the coking section of the regenerator adopts a two-stage radial flow combined bed structure. The screen of the burnt section is changed from the first and second generation cylindrical to conical to improve the defects of the original cylindrical screen with uneven temperature distribution and uneven catalyst flow. In 1991, IFP launched the second-generation continuous catalytic reforming process with a reaction pressure of 0.35MPa and a regeneration pressure of 0.55MPa. The regenerator is changed from the first generation of fixed bed to runoff moving bed. At the top of the regenerator is the catalyst storage area, and there are four independent areas below: the main combustion area, the final combustion area, the oxychlorination area, and the burning area. The charred part of the regenerator adopts a two-stage runoff moving bed structure with high efficiency.

Both UOP third-generation and IFP second-generation continuous catalytic reforming regeneration processes adopt a two-stage radial-flow moving bed structure in the coking section. The large air flow leads to high power consumption; (2) The inlet temperature of the regeneration gas in the first stage is high, and the heat released by charring cannot be fully utilized; (3) The temperature distribution along the runoff of the charred section is uneven, An over-temperature area is prone to appear at the screen in one section; (4) The utilization rate of the burnt section is low.

The purpose of the present invention is to provide a method that conforms to the charcoal burning mechanism so that the oxygen in the regeneration gas can be fully utilized, thereby reducing the amount of regeneration gas and lowering the bed temperature. The fully utilized reforming catalyst continuous two-stage axial flow combined bed regeneration process method and equipment.

The present invention is realized through the following technical solutions:

The reforming catalyst continuous two-stage axial flow combined bed regeneration process method of the present invention includes burning off of catalyst carbon deposits, catalyst chlorination and oxidation, separating the chlorination and oxidation zone from the catalyst carbon deposit burning zone, and catalyst carbon deposit burnout The process is:

a. The deactivated catalyst particles discharged from the reforming reaction system enter the regeneration zone;

b. In the first zone of the regeneration zone, the deactivated catalyst particles are in parallel flow contact with the regeneration gas in the same direction, and burn 60-80% of the carbon deposit on the deactivated catalyst;

c. The catalyst particles that have completed most of the charring in the first zone of the regeneration zone enter the second zone of the regeneration zone;

d. The mixture of regeneration flue gas flowing out of the first zone, supplementary air and quenching gas is in the second zone of the regeneration zone, and the catalyst particles flowing down from the first zone are in parallel contact with the catalyst particles flowing down from the first zone, and the remaining gas is burned. of carbon deposits.

The reforming catalyst continuous two-stage axial-flow combined bed regeneration process method of the present invention also includes: the temperature at the inlet of the regeneration gas in the first zone of the process b is 445°C-465°C.

The reforming catalyst continuous two-stage axial flow combined bed regeneration equipment of the present invention comprises an upright container with a catalyst charcoal burning area and a chlorine oxidation area inside, a catalyst distributor 5 inside the upright container, a catalyst inlet 4 on the top, and regeneration gas on the side Inlet 3, supplementary air and quench air inlet 2, regeneration gas outlet 1, the catalyst distributor 5 is funnel-shaped, the edge is connected to the inner wall of the upright container, and the lower end is connected to the feeding channel 6; below the catalyst distributor 5, there are first The first section of axial flow moving bed 8 and the second section of axial flow moving bed 10; the lower part of axial flow moving bed 8, 10 is composed of conical screen 9, the upper edge of conical screen 9 is connected with the inner wall of the upright container, and the feeding channel 6 is connected to the lower end of the conical screen 9; the lower part of the axial flow moving bed 10 of the second section is separated from the chlorination oxidation zone 11, and the end of the feeding channel 6 at the lower end of the conical screen 9 communicates with the chlorination oxidation zone 11.

The reforming catalyst continuous two-stage axial flow combined bed regeneration equipment of the present invention also includes:

Catalyst distributor 5 and the feeding channel 6 of conical screen cloth 9 lower ends are respectively made of more than two garden pipes.

The feed channel 6 at the lower end of the catalyst distributor 5 and the conical screen cloth 9 can be formed by a complete annular pipe.

The conical screen cloth 9 upper center of axial-flow moving bed 8,10 can connect inner pipe 7, and inner pipe 7 is the garden pipe that upper end is closed, forms annular space with the inwall of upright container.

The cylinder or annular space of the axial flow moving bed 10 can be divided into more than two channels.

The regeneration gas inlet is located in the upper part of the vertical container and in the middle of the feed channel 6 at the lower end of the catalyst distributor 5; the supplementary air and quenching gas inlet is located in the middle of the vertical container and in the middle of the feed channel 6 at the lower end of the first section of the axial flow moving bed; the regeneration gas outlet It is located in the middle part of the feeding channel 6 at the lower part of the vertical container and the lower end of the second section of the axial flow moving bed.

The present invention adopts a brand-new two-stage axial-flow moving bed combined process technology. Compared with two-stage radial-flow moving bed, it can realize the uniform distribution of bed temperature along the radial direction, and the bed temperature is easy to control. It can be adjusted flexibly to make full use of the oxygen in the regeneration gas, and the flow rate of the regeneration gas can be reduced by nearly 40%. The ratio can be flexibly adjusted within the range of 60-80%. The total effective bed height of the two-stage axial flow bed can be controlled within 2.5 meters, and the equipment utilization rate of the coking section is relatively high.

The accompanying drawings of the present invention are as follows:

Fig. 1 is a structural diagram of device embodiment 1 of the present invention;

Fig. 2 is a detailed structure diagram of the regeneration gas outlet section of Embodiment 1 of the equipment of the present invention;

Fig. 3 is the sectional view of Fig. 2 of the present invention;

Fig. 4 is another cross-sectional view of Fig. 2 of the present invention;

Fig. 5 is a structural diagram of Embodiment 2 of the device of the present invention.

The present invention is proposed on the basis of research on coking dynamics and fluid mechanics mechanism of moving bed. Through the study of carbon burning kinetics, it is found that there are three types of carbon deposits with large differences in combustion performance on the reforming catalyst, which are called type I carbon, type II carbon and type III carbon respectively. Type I char burns faster and has a lower ignition temperature. Through the hydrodynamic research on the axial flow and radial flow moving bed, it is found that many hydrodynamic characteristics of the axial flow moving bed are more suitable for the coking mechanism of the reforming catalyst.

The principle of the invention is: adopting the moving bed process, the regeneration gas passes through the entire coking section along the axial flow at one time so that the oxygen in the regeneration gas can be fully utilized; the regeneration gas and the catalyst flow downward in the same direction and can be heated by the heat of I-type charcoal combustion The catalyst in the bed makes it reach the light-off temperature of type II and type III charcoal, so that the inlet temperature of the first stage of regeneration gas can be reduced accordingly, and the heat of charcoal burning can be fully utilized; due to the use of two stages of axial flow moving bed The process can control the scorching amount and maximum temperature of the first stage through the oxygen content of the first stage, so the operation is flexible and the adjustment is convenient.

The reforming catalyst regeneration method of the present invention comprises the burning off of catalyst carbon deposit, catalyst chlorination and oxidation, and the chlorination and oxidation zone is separated from the catalyst carbon deposit burning zone, and the catalyst carbon deposit burning process is as follows:

a. The deactivated catalyst particles discharged from the reforming reaction system enter the regeneration zone by weight;

b. In the first zone of the regeneration zone, the deactivated catalyst particles contact with the regeneration gas with a lower inlet temperature in the same direction and flow downwards, and burn 60-80% of the carbon deposit on the deactivated catalyst;

c. The catalyst particles that have completed most of the charring in the first zone of the regeneration zone enter the second zone of the regeneration zone by weight;

d. The mixture of the regeneration flue gas flowing out of the first zone, the supplementary air and the quenching gas is in the second zone of the regeneration zone, and the catalyst particles flowing down from the first zone are in parallel contact with the catalyst particles in the same direction, and the lost gas is burned off. Coke deposits remaining on live catalysts.

Example 1 of the equipment of the present invention adopts the following design, the top of the two-stage axial-flow combined bed is a catalyst distributor 5, the lower part of the distributor 5 is the first-stage axial-flow bed 8, and the bottom of the first-stage axial-flow bed is a conical screen. 9. The lower part of the conical screen 9 is the second section of the axial flow bed 10, and the lower part of the second section of the axial flow bed is the chlorine oxidation section 11. The axial flow beds 8 and 10 are axially divided into a honeycomb structure, and the number of divisions can be 4, 6, 12 or more, and can also be determined according to the size of the outer cylinder. The principle is to ensure that the catalyst moves down evenly. Distributor 5, the bottom of tapered screen cloth 9 are all connected to feed pipe 6, and feed pipe 6 can be many garden pipes, and the quantity of garden pipe can be separated into honeycomb structure quantity consistent with axially. The feeding pipe 6 can also be a complete annular cylinder formed by two plates. The regeneration gas inlet is located in the upper part of the vertical container and in the middle of the feed channel 6 at the lower end of the catalyst distributor 5, the supplementary air and quenching gas inlet is located in the middle of the vertical container and in the middle of the feed channel 6 at the lower end of the first section of the axial flow moving bed, and the regeneration gas outlet It is located in the middle part of the feeding channel 6 at the lower part of the vertical container and the lower end of the second section of the axial flow moving bed. The lower part of the axial-flow moving bed 10 of the second section is separated from the chlorination and oxidation zone 11, and only the end of the feeding channel 6 at the lower end of the conical screen cloth 9 communicates with the chlorination and oxidation zone 11.

The device of the present invention includes the following steps when working: (1) The catalyst enters the distributor 5 through the material leg 4 for redistribution. (2) The catalyst entering the catalyst distributor 5 uniformly flows into the first stage axial flow bed 8 along the feed pipe 6 . (3) The regeneration gas coming in from the first-stage regeneration gas inlet 3 is the same as the catalyst entering the first-stage axial flow bed 8

It flows downward in the form of a moving bed, and the catalyst enters the second section through the conical screen 9 and the feeding pipe 6

Axial flow bed 10, the regeneration gas flows out through the pores of the conical screen 9 and comes from the regeneration gas inlet of the second stage

2, the air mixed with the quench air flows downward together with the catalyst. (4) The catalyst flowing in the second stage axial flow bed 10 enters the chlorine oxygen after passing through the conical screen and the feeding pipe 6.

Paragraph 11. (5) The gas flowing down in the second section of the axial flow bed 10 flows out through the pores of the conical screen 9 and then passes through the second section

The regeneration gas is discharged from outlet 1.

Example 2 of the equipment of the present invention adopts the same design as that of Embodiment 1, the difference is that an inner pipe 7 is connected to the center of the upper end of the conical screen 9 of the axial flow moving bed 8, 10, and the inner pipe 7 is a closed garden pipe at the upper end. , it forms an annular space with the inner wall of the upright container, and the distributor 5 and the lower end of the first section axial flow bed 8 conical screen 9 lower channel 6 extend into the annular space.

Claims (8)

1. reforming catalyst continuous two section axial flow combined bed process of regenerating comprise burn off, catalyzer chlorination and the oxidation of catalyst carbon deposit, it is characterized in that: chloride oxidation district catalyst carbon deposit burn off is separated out, and catalyst carbon deposit burn off process is:

A. the deactivated catalyst particles of discharging from the reforming reaction system enters the breeding blanket;

B. deactivated catalyst particles contacts 60～80% carbon deposit on the burn off decaying catalyst with the downward in the same way also stream of resurgent gases in first district of breeding blanket;

C. in first district of breeding blanket, finish granules of catalyst that major part makes charcoal and enter second district of breeding blanket;

D. also flow downwards in the same way with the granules of catalyst that flows down by first district in second district of breeding blanket with the mixed mixed gas of chilling gas with additional air by the effusive regenerated flue gas in first district and contact the remaining carbon deposit of burn off.

2. reforming catalyst continuous two section axial flow combined bed process of regenerating according to claim 1 is characterized in that: process b first district's resurgent gases temperature in is 445 ℃～465 ℃.

3. reforming catalyst continuous two section axial flow combined bed reclaim equiments, comprise a upright vessel, in have catalyzer make charcoal the district and chlorine oxidation zone, there are catalyst dispenser 5, top that catalyst inlet 4 is arranged in the upright vessel, there are resurgent gases inlet 3, additional air and quench gas inlet 2, resurgent gases outlet 1 in the side, it is characterized in that: catalyst dispenser 5 is funnel-form, and the edge is connected with the upright vessel inwall, and the lower end is communicated with blanking channel 6; Catalyst dispenser 5 belows are arranged with first section axial flow moving-bed 8 and second section axial flow moving-bed 10 successively downwards; The bottom of axial flow moving-bed 8,10 is made of taper screen cloth 9, and the top edge of taper screen cloth 9 is connected with the upright vessel inwall, and blanking channel 6 is connected the lower end of taper screen cloth 9; Separate in second section axial flow moving-bed 10 bottoms and chloride oxidation district 11, and the end of the blanking channel 6 of taper screen cloth 9 lower ends communicates with chloride oxidation district 11.

4. reforming catalyst continuous two section axial flow combined bed reclaim equiments according to claim 3 is characterized in that: the blanking channel 6 of catalyst dispenser 5 and taper screen cloth 9 lower ends is made of the garden pipe more than two respectively.

5. according to claim 3,4 described reforming catalysts continuous two section axial flow combined bed reclaim equiments, it is characterized in that: the blanking channel 6 of catalyst dispenser 5 and taper screen cloth 9 lower ends can be made of a complete ring pipe.

6. reforming catalyst continuous two section axial flow combined bed reclaim equiments according to claim 3, it is characterized in that: pipe 7 in the center, taper screen cloth 9 upper end of axial flow moving-bed 8,10 bottoms can connect, the garden pipe that interior pipe 7 is upper end closeds is with the inwall looping space of upright vessel.

7. reforming catalyst continuous two section axial flow combined bed reclaim equiments according to claim 3 is characterized in that: the garden tube or the annular space of axial flow moving-bed 10 may be partitioned into plural passage.

8. reforming catalyst continuous two section axial flow combined bed reclaim equiments according to claim 3 is characterized in that: resurgent gases inlet is positioned at upright vessel top and at the middle part of catalyst dispenser 5 lower end blanking channels 6; Replenishing air and quench gas inlet is positioned in the middle part of the upright vessel and the middle part of the blanking channel 6 of first section axial flow moving-bed lower end; The resurgent gases outlet is positioned at the middle part of the blanking channel 6 of upright vessel bottom and second section axial flow moving-bed lower end.

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