SU1184556A1 - Reactor for cracking of hydrocarbon raw material - Google Patents

Abstract

1. HYDROCARBON CRACKING REACTOR, comprising a housing within which a cracking section with a distribution grid with gas collection and overflow pipes and vertically mounted guide baffles with inclined segments in the upper part fixed to the housing and with a stripper section with located inside it is a grate with overflow pipes and collecting devices, with fittings for input of regenerated catalyst and water vapor, bottom with fitting for withdrawal of coked catalyst and nozzles for the withdrawal of reaction products with water vapor, which are characterized by the fact that, in order to increase productivity, decrease catalyst removal, increase product quality and prevent coke formation, it is equipped with partition walls placed between the K1 1 DIMI partitions below the level of the upper end of segments that form together with the housing from (L stand-separation chamber, in the upper part of which are placed fittings for the withdrawal of reaction products with water vapor), for example partitions respectively having openings formed downcomers. 2. The reactor according to claim 1, characterized by the fact that the partition walls are provided with plates fixed to the bottom end.

Description

1 The invention relates to a reactor design for. the processes of catalytic cracking of distillate petroleum and catalytic upgrading of unsteady and chemical unstable gasolines in the moving bed of the granular catalyst and can be applied at refineries and petrochemical plants. The purpose of the invention is to increase the productivity of the reactor, reduce the removal of catalyst crumb from the reactor, improve catalyst stripping and prevent coking on the inner wall of the reactor. Fig, 1 shows the apparatus, a longitudinal section; figure 2 - the same cross section. The reactor contains a housing 1 with nozzles for introducing fresh raw material 2, regenerated catalyst 3, water vapor 4 and fittings for extracting reaction products with water vapor 5 and coked catalyst 6, cracking section SF 7 with a distributor 8 for introducing regenerated catalyst, basic 9 and additional 10 vertical guide partitions with inclined plates 11 and transfer windows 12. At the bottom of the cracking section 7 there is a distribution slat 13 with evenly spaced vertical hectares by suction pipes with caps 14 for taking the reaction products out of the catalyst bed and overflow pipes 15 for descending the coked catalyst from the cracking zone to the stripping section 16. In the distribution grid 13 there are openings 17 for passage of the vapors of the reaction products and water vapor to the ring sludge. but the separation section 18, below the horizontal section 16, is a horizontally assembled grid 19, into which is assembled a collection device 20 for feeding the catalyst from the stripping zone to the fitting 6, fixed in the bottom 21 to remove catalyst from the reactor. A fitting 23 with a distribution manifold for supplying water vapor is mounted in the reactor cover 22. 6 The newly created annular settling separation section 18 is formed by welding to the vessel 1 and the distribution grid 13 of eight eight vertical partitions 9 and eight and eight inclined plates 11 that cut eight segments on the distribution grid 13 (in plan). . In the upper part, the vertical partitions are hermetically connected to the vessel I of the reactor by inclined segments 24. At the top of this annular zone, four nozzles 5 are mounted into the reactor vessel at a height of 1.8-2.1 m from the grid 13 to discharge the vapors from the reactor to the column. In the lower part of the vertical partitions 9, eight windows 12 are cut through - two on each side of the partition. This creates an annular (continuous at the reactor vessel) chamber to discharge the vapor from the apparatus. In order to create the required cross-sectional area for the passage of vapor from under the lattice space into the annular sedimentation separation zone in the distributor ™ lattice 13, two rows of holes I7 are cut evenly along two circles. The inclined plates 11 prevent these holes from coming out of the catalyst from the cracking zone raw material 7. An expelled section of increased volume is created between the distribution 13 and the national grid 19. The reactor works as follows. Fresh raw materials are fed to reactor vessel 1 through nozzle 2, and the catalyst through nozzle 3 and switchgear 8 to cracking section 7. Reaction products from the cracking section are fed through the caps 14 beads under the distribution grid 13. Coked catalyst is transferred from the cracking section the pipes 13 are sent to the stripping section 16, and from there with help; and the collecting device 20 is discharged through the fitting 6 to the regeneration. To remove adsorbed heavy hydrocarbons from the catalyst, steam is supplied to the stripping section 16 through fitting 4, located E (Iis under the collecting grid 19. The reaction product pairs and the water vapor from under the grid 13 through the openings 17 the separation section 18, where the catalyst chips and dust are separated from the vapor. Purified vapors are directed through three geshem pipelines to the distillation column through the outlet nozzles 5. Water vapor is introduced through the fitting 23 into the upper bottom of the reactor. the reactor is installed 43-102, catalytic cracking is subjected to a sulfur vacuum distillate, having a density of 0.895 g / cm, a fraction of boiling to 350 ° C, 11 May by weight, boiling point 520 ° C and a sulfur content of 1.79% by weight. As a catalyst, a zeolite-containing 11-5th globular catalyst with rare-earth elements, the Zeocar-2 catalyst with a density of 0.745 g / cm containing a working fraction in the amount of 92.6 wt.% and having a catalytic activity for gasoline output of 48.5 wt.%, are used. 52 t / h (or 1248 t / s with a temperature of 465 ° C. Are fed into the reactor 1 through nozzles 2. The catalyst (75 t / h) is introduced into the reactor with a temperature of 550 ° C over fitting 3, then through switchgear 8 to the cracking section of the raw material 7. The processing in the reactor is carried out at 460 ° C raw material, in the middle of the cracking section the raw material flow rate is 2 h and the catalyst circulation ratio is 1.44 tons / ton of raw material (Table 1). The pressure at the top of the reactor is maintained 0, 53 at the expense of the organization of the ring output of vapor from the reaction zone, in contrast to the maximum allowable value of 0.7 a ti for this apparatus and 0.67 ati - on the prototype (see table 1. The pressure drop in the cracking section of the raw material is maintained at the same level (o, 07 atm), although the capacity of the plant is increased from 49.2 to 52.0 t / h (see Table 2). The coked catalyst from the cracking zone through the flow pipes 15 is sent to the stripping section 16, where using water vapor supplied at a temperature of 47 ° C through fitting 4 under the combined grid 19, the stripping takes place adsorbed hydrocarbons from the catalyst. The residence time of the catalyst in the stripping section of the reactor is maintained for 7 min. by increasing the height of the catalyst bed from 0.69 to 0.99 m (and, accordingly, the volume of the catalyst in this zone) instead of the 4.9 min of the prototype. After stripping, the catalyst in collecting device 20 through outlet 6 with a temperature of 445 C is removed from the reactor for regeneration. The vapors of the reaction products from the cracking zone of the raw material 7 and water vapor from the stripping section 16 are fed through holes 17 in the distribution grid 13 into an annular settling and separation section 18 with a width of 250 mm and a height of 1.9 m (from the distribution grid to nozzles 5 of the vapor outlet or 2.8 m from the catalyst level in the stripping section to the nozzles 5j, in section 18, the vapor is separated from the catalyst crumb and dust.From the separation and separation section of the pair through nozzles 5 they are removed from the reactor to the distillation column by three streams in three helmets The yield of gasoline is 27.3% by weight of the raw material and the amount of light 54.2%, while the prototype of the light products is 53.8% by weight of Table 3. Example 2. In a new reactor, sulfur dioxide distillate is subjected to catalytic cracking the zeolite-containing Zeocar-2 catcher, the quality of which is given in Example 1. The reactor capacity for raw materials is increased from 52 to 54.2 t / h / up to 1300 t / day instead of 1180 t / day by a known method). The raw material with a temperature of 468c is introduced into the vessel 1 of the reactor through nozzles 2. The catalyst in an amount of 75 tons per hour with a temperature of 555 ° C is introduced into the reactor through the fitting 3 and through the distribution device 8 is distributed evenly over the cross section of the reactor. The processing of raw materials in the reactor is carried out at 460 ° C (in the middle of the cracking section), the volumetric feed rate of the raw material is 2.1 and the circulation ratio of the catalyst 1, the raw material (see table. |). The pressure of the reactor is maintained at 0.56 atm versus 0.67 atm per prototype (Tables 1, 2). The pressure drop in the cracking section (top-bottom) was 0.08 atm, i.e. the same magnitude as the willow of the prototype (see Table 2). the productivity of the reactor was increased in terms of raw materials. This became possible due to the creation of a circular one (along the periphery of the cross section of the reactor

pa sedimentation separation section 18 for evacuating the vapor from the cracking zone 7, coked catalyst From the cracking zone 7, the permeable tubes 15 are sent to the stripping section 16, in which the adsorbed hydrocarbons are stripped with steam at a temperature of 470 ° C fitting 4. The residence time of the catalyst from the stripping section of the reactor is maintained at 7.8 minutes by increasing the height of the catalyst bed in it to 1.1 m. Then the catalyst after stripping with a temperature of 443 ° C is removed from the collecting grid 19 device va 20 through the nozzle 6 from the reactor for regeneration. In spite of the increased productivity of the reactor in terms of raw materials, the depth of transformation of the vacuum distillate (cracking raw material) is not

only it did not decrease, and even slightly increased from 71.3 to 71.8 May.7 ,. The output of gasoline 27.3 and the amount of light 54.2 wt.% From raw materials. The selectivity of the process has been preserved.

level in comparison with the prototype.

The quality of the obtained products of catalytic cracking — gas, gasoline, light and heavy catalytic gas oils — remained almost unchanged in comparison with the prototype, except for the content of mechanical admixtures in heavy gas oil, the amount of which was reduced by 8-10 times,

Table I

Productivity by raw materials:

t / day

t / h

m / h

The temperature in the middle of the cracking zone of raw materials, with

The amount of catalyst in the reactor, m

Volumetric feed rate, 5

Amount of circulating catalyst, t / h

Volume of circulating catalyst, m / h

Catalyst circulation ratio, t / t

Sfya

12481300 52.0 54.2 58.0 60.5

460460

29

29

2.0 2.1

75

75

101101

1.53

1.44 1.38

Indicators

k66

0.67

1350

- No 550 150

2050

470 465

550 446 0.048

1184556, 8

Continuation of table 1

By examples

52 55 0.53 0.56

10001000

150100

300300

150150

16001550

11.7 13.1

8.2 7.0 7.8

4.9

470470

465468

550555

445443 0.006 0.005

118012481300

49,252,054,2 0,670,530,56

0,590,460,48 0,380,250,27

0,270,170,18

0, 080.070.08

7.86.87.8

Maximum allowable working pressure 0.7 MPa

Indicators

The raw material: t / day wt.%

Received products, wt.% From raw materials:

greasy gas

118455610

table 2

T a b l and c a 3

By examples

1180

1248 1300 100.0 100.0 100.0

13.9

13.9 14.0

n

Indicators

now

light gas oil heavy gas oil coke + loss total

The total depth of conversion of raw materials, wt.%

Selectivity of the process:

gasoline output / total turning depth

gasoline output / gas output

118455612

Continuation of table 3

71.3

,eight

0.382 0.38

0.380

1.97

1.95

1.95

Phie.1

20

FIG. Z

Claims (2)

1. REACTOR OF A HYDROCARBON RAW MATERIAL CRACKING, comprising a housing, inside of which a cracking section with a distribution grid with gas collection and transfer pipes and vertically mounted guide walls with inclined segments in the upper part mounted on the housing, and a stripping section located inside it with a booster grill with transfer pipes and prefabricated devices, Kapiku with fittings for the input of the regenerated catalyst and water vapor, the bottom with a fitting for the discharge of coke of the cured catalyst and fittings for the withdrawal of reaction products with water vapor, characterized in that, in order to increase the productivity of reducing the removal of the catalyst, improve the quality of the product and prevent coke formation, it is equipped with additional baffles with inclined segments located between the guide baffles below the upper end face and forming together with a casing, a settling-separation chamber, in the upper part of which there are fittings for withdrawing reaction products with water vapor, into the guide x partitions formed downcomers hole. 2. Reactor pop. ^ characterized in that the guide walls are provided with plates fixed to the lower end. 1 1 184556