Title of Invention

"CATALYTIC CRACKING PROCESS OF PETROLEUM HYDROCARBONS."

Abstract The present invention discloses a catalytic cracking process of petroleum hydrocarbons and a double-pipe type of riser reactor used therein. In the present invention, a catalyst is fed via an inlet tube to an inner tube and an annular reaction space between the inner and outer tubes of the double-pipe type of riser to contact with a hydrocarbon oil feedstock and is subjected to reaction, then a reaction stream thus produced flows into a separation apparatus via a confluence tube to separate the reaction oil-gas from a spent catalyst, the spent catalyst is stripped and regenerated, then the regenerated catalyst is recycled for reuse. The process of the present invention can improve both product distribution and product properties of FCC process.
Full Text Technique field
The present invention relates to a catalytic cracking process of petroleum hydrocarbons in the absence of hydrogen.
Technique background
Although catalytic cracking process has been developed for several decades and formed a relatively complete system of techniques, refiners are still studying and searching untiringly to seek for a process not only meeting the requirements of increasingly rigorous environmental laws and regulations but also according with the change of market demands so as to create satisfactory economic benefit for enterprises .
USP 5043522 and USP 5846403 relate to the improvements of conventional catalytic cracking process, in which part of catalytic gasoline is fed to a riser reactor at upstream of the nozzle for feeding stock oil to contact and react with a regenerated catalyst having high activity at a high temperature, so that the yields of light olefins such as propylene, butylene and the like are increased, meanwhile the octane number of gasoline is improved.
CN 1279270 A discloses a process for increasing simultaneously yields of both liquefied gas and diesel oil. In this process, a catalytic gasoline is also fed to a riser reactor at upstream of feedstock oil nozzles to contact at first and then react with a regenerated catalyst. This part of reprocessed catalytic gasoline is cracked fully at a high temperature under a large catalyst-oil ratio to form a great quantity of liquefied gas. Meanwhile coke is deposited on the catalyst in a minute quantity, so that the catalyst activity is reduced appropriately in favor of producing more diesel oil.
USP 3894933 discloses a catalytic cracking process with two riser reactors sharing a settler. In this process, a light cycle oil is fed to a riser reactor to contact and react with a regenerated catalyst, resulting in a conversion less than 30% ; the reacted catalyst is fed to another riser to contact and react with a fresh feedstock and heavy cycle oil.
CN 1069054 A discloses a flexible and multi-effective catalytic cracking process of hydrocarbons. This process relates to two independent riser reactors and two sedimentation
separation systems attached with the risers. In the first riser reactor, a light hydrocarbon is contacted and reacted with a regenerated catalyst under conditions of a temperature of 600-700°C, a catalyst-oil ratio of 10-40, a reaction time of 2-20 seconds, and the carbon content of the catalyst being controlled in the range of 0.1-0.4% by weight ; the reacted catalyst is fed to the other riser to contact and react with heavy hydrocarbons under conventional catalytic cracking reaction conditions.
Both USP 4820493 and CN 1174094 A expand the diameter of the pre-lifting section of the riser reactor, in which an inner tube for transferring catalyst is set coaxially to improve the contacting effect of oil and catalyst and to increase yield of desired product. Said inner tube for transferring catalyst is located at a place below the feed nozzle of hydrocarbon oil.
Both USP 4310489 and CN 1096047A use a catalytic cracking unit with two risers. Therein, a riser is used to treat a heavy feedstock of conventional catalytic cracking, the other riser is used for catalytic modifying poor diesel oils or heavy gasoline fractions.
In sum, the catalytic conversion processes for treating simultaneously light oil and heavy oil, disclosed in the prior art, can be essentially divided into two categories: (1) using a single riser reactor and setting the light feedstock inlet at upstream of heavy feedstock inlet, and (2) using two riser reactors and treating different feedstocks in different risers. The first category of the processes need a little modification on equipment; however, reaction conditions of light oils are basically fixed, and product distribution and product properties can hardly be improved by means of optimization of operation variables. The second category of the processes overcome disadvantages of the first category of processes, operation conditions of each riser can be adjusted independently to carry out each reaction under respective conditions adapted to different feedstock oils. However, for the second category of the processes, costs in both construction of unit and reconstruction of equipment are increased significantly. Furthermore, in practical industrial production, a complicated flowchart will greatly increase the difficulty in operation.
Summary of invention
An object of the present invention is to provide a catalytic cracking process of petroleum hydrocarbons using a double-pipe type of riser reactor, which can provide hydrocarbon oil feedstocks having different properties with suitable reaction conditions and
improve obviously the product distribution and product properties of the catalytic cracking process.
Another object of the present invention is to provide a relaying cracking process of petroleum hydrocarbons, which can make the catalytic cracking process of petroleum hydrocarbons not only have a desirable ability to convert heavy oils and better product selectivity but also simplify flowchart and easy to operate.
The catalytic cracking process provided in the present invention comprises the following steps:
(1) feeding a catalyst via an inlet tube to on inner tube and an annular reaction space between inner and outer tubes of a double-pipe type of riser reactor, which flows upward under an action of pre-lifting media;
(2) feeding a hydrocarbon oil feedstock to the inner tube and the annular space between the inner and outer tubes of the reactor to contact with the catalysts therein to form a oil-catalyst mixture, so that the reaction of the hydrocarbon oil feedstock is carried out under catalytic cracking reaction conditions, and the reaction streams including the reaction oil-gas and catalyst, flow upward along vessel wall.
(3) the reaction streams both from the inner tube and from the annular space between the inner and outer tubes flow together at the inlet of a confluence tube, then the mixed stream enters a separation apparatus via the confluence tube, where the reaction oil-gas is separated from the reacted and carbon-deposited catalyst ;
(4) further separating the reaction oil-gas into various products including gasoline, diesel oil and liquefied gas, the reacted and carbon-deposited catalyst is stripped and regenerated, and the regenerated catalyst is recycled to the reactor for reuse.
Another catalytic cracking process of petroleum hydrocarbons provided in the present invention mainly comprises the following steps:
(1) feeding a regenerated catalyst to the bottom of a double-pipe type of riser reactor via a catalyst inlet tube, which flows upwards under an action of a pre-lifting media ; 20-80% by weight of the regenerated catalyst flows into the inner tube, and the remaining part of the catalyst enters the annular reaction space between the inner and outer tubes and flows upward under an action of the pre-lifting media ;
(2) feeding a hydrocarbon oil feedstock to the inner tube of the reactor to contact with the catalyst therein to form a oil-catalyst mixture, so that the reaction of the hydrocarbon oil feedstock is carried out under catalytic cracking reaction conditions, the reaction stream including the reaction oil-gas and the catalyst flow upward along vessel wall;
(3) The reaction stream from the inner tube and the regenerated catalyst (stream) from the annular reaction space flow together at the confluence tube inlet of the reactor, and the the reaction oil-gas is reacted continuously under catalytic cracking conditions; the formed reaction stream is introduced in to a separation apparatus via the confluence tube, where the reaction oil-gas is separated from the reacted and carbon-deposited catalyst;
(4) The reaction oil-gas is further separated into various products including gasoline, diesel oil and liquefied gas; the reacted catalyst is stripped and regenerated, and regenerated catalyst is recyded to the reactor for reuse.
In comparison with the prior art, beneficial effects of the present invention are mainly embodied in the following aspects:
The processes provided in the present invention are simple in equipment and flexible in operation. Not only the reactions of heavy oils and light oils can be carried out separately in isolated reactors, but also reaction conditions can be regulated flexibly according to physico-chemical properties and mass flow of different feedstocks, which thus create favorable conditions for improving product distribution and product quality.
The processes provided in the present invention can make flexible arrangements of several production schemes such as, for example, gasoline scheme, diesel oil scheme, liquefied gas scheme, light olefins scheme and the like. Therefore, oil refining enterprises car adjust product distribution pattern in time by using the processes of the present ivention in accordance with variation of market demand so as to obtain more profitably economic benefit.
The processes of the present invention can obviously improve catalytic cracking product distribution, reduce yields of dry gas and coke, increase yields of high value products such as liquefied gas, gasoline and/or diesel oil and the like.
Furthermore, the processes provided in the present invention can also improve the product quality and reduce the environmental pollution caused by petroleum products. It is
proved by test that the processes can decrease olefin content of gasoline and increase the octane number of gasoline, reduce freezing point of diesel oil, improve sensibility of the diesel oil to flow modifiers, increase stability of the diesel oil meanwhile, the processes have a certain effect in reducing contents of the impurities such as sulfur, nitrogen and the like in gasoline and diesel oils .
Ilustration of Figures
Figure 1 is a schematic structure diagram of a double-pipe type of riser reactor having a single channel for feeding catalyst.
Figure 2 is a schematic structure diagram of joint regions for an inner tube, an outer tube and a confluence tube in a double-pipe type of riser reactor having a single channel for feeding catalyst.
Figure 3 is a schematic diagram of setting modes of feed nozzles of an inner tube and an outer tube in a double-pipe type of riser reactor having a single channel for feeding catalyst.
Figure 4 is a schematic structure diagram of a double-pipe type of riser reactor having two channels for feeding catalyst.
Figure 5 is a schematic structure diagram of joint regions for an inner tube, an outer tube and an confluence tube in a double-pipe type of riser reactor having two channels for feeding catalyst.
Figures 6-9 are principle flowcharts of the catalytic cracking processes of petroleum hydrocarbons using a double-pipe type of riser reactor
Figure 10 and 11 are principle flowcharts of the relaying cracking process of petroleum hydrocarbons.
Detailed Description of Invention
The double-pipe type of riser reactor is used both in the catalytic cracking process of petroleum hydrocarbons and in the relaying cracking process of petroleum hydrocarbons of the present invention. Said double-pipe type of riser reactor may have a single channel or two channels for feeding catalyst, or other reactors having similar structure. The structure of the double-pipe type of riser reactor is detailedly illustrated herein below in combination with the Figures.
In the present invention, said double-pipe type of riser reactor with a single channel for feeding catalyst has a structure shown in Figure 1. The reactor mainly includes the following members: regenerated catalyst inlet tube 1, inner tube 2, outer tube 3, confluence tube 4, pre-lifting distribution rings 5, 6 and 7, and feed nozzles 8 and 9 ; wherein the inner tube 2 and outer tube 3 are coaxial, and the ratio of the inner cross-section area of the inner tube to the cross-section area of the annular space between the inner and outer tubes is 1: 0.1-10, preferably 1: 0.2-2; the lower end of the inner tube 2 is located at a place above the inlet of regenerated catalyst, the inner tube has a length amounting to 10-70%of the total length of the reactor, preferably 20-60% ; one end of the confluence tube 4 is connected with the upper end of the outer tube 3, and the other end is connected with a gas/solid separation apparatus, the cross-section area ratio of the confluence tube 4 and the inner tube 2 is 1: 0.2-0.8 ; the pre-lifting distribution rings 5, 6 and 7 are located at the bottoms of the reactor, inner tube and outer tube respectively. Fixing member 10 may be installed in multi-lines, for example, with 2-12 lines of shrouding wires or draw-bars between the inner and outer tubes according to the specific size of the reactor and requirement in engineering.
In the double-pipe type of riser reactor having a single channel for feeding catalyst, the distance from the upper end of the inner tube (i.e. the outlet end of the inner tube) to the outlet end of the confluence tube is 1-30 meters (i.e., total length of the confluence tube), preferably 2-20 meters. Different types of the joint modes between the inner tube, the outer tube and the confluence tube may be set in accordance with requirements. Figure 2 exemplifies four embodiments of the joint modes in the present invention, but does not infend to limit the present invention.
As shown in Figure 2, in the embodiment A the upper end of the inner tube is in a straight tube shape, and the outer tube is also in a straight tube shape, both the inner diameters of the confluence tube and the outer tube are the same. The inner tube has an inner diameter of D1, the confluence tube has an inner diameter of D2, and Dl: D2 = 0.4-0.9: 1.
As shown in Figure 2, in the embodiment B, the upper outlet section of the inner tube is diverged in diameter, the outer tube is a straight tube, and both the confluence tube and the outer tube are equal in inner diameters. The inner tube has an inner diameter of Dl and the confluence tube has an inner diameter of D2. The ratio of the height H1 of the upper outlet
section of the inner tube to the inner diameter Dl of the inner tube is 0.5-3: 1. The divergence angle a of the upper outlet section of the inner tube is 5-30°.
As shown in Figure 2, in the embodiment C, the upper outlet section of the inner tube is diverged in diameter, and the outer tube is converged in diameter and then connected with the confluence tube. The inner tube has an inner diameter of Dl and the confluence tube has an inner diameter of D2. The ratio of the height H2 of the upper outlet section of the inner tube to the inner diameter Dl of the inner tube is 0.5-3: 1. The divergence angle b of the upper outlet section of the inner tube is 5-30°. The bottom end of the converged section of the outer tube is located between 1.0 D2 above the inner tube outlet and 1.0 D2 below the inner tube outlet with the convergence angle c of 10-60°. The ratio of the height H3 of the converged section of the outer tube to the inner diameter D2 of the confluence tube is 0.5-3.0: 1.
As shown in Figure 2, in embodiment D, the upper end of the inner tube is in a straight tube shape, and the outer tube is converged in diameter and then is connected with the confluence tube. The inner tube has an inner diameter of Dl and the confluence tube has an inner diameter of D2. The bottom end of the converged section of the outer tube is located between 1.0D2 above the inner tube outlet and 1.0D2 below the inner tube outlet with the convergence angle d of 5-45°. The ratio of the height H4 of the converged section in the outer tube to the inner diameter D2 of the confluence tube is 0.5-3.0: 1.
As shown in Figure 3, three kinds of designs for diverged, equal and converged diameters may be used to the lower end of the inner tube in the double-pipe type of riser reactor having a single channel for feeding catalyst. The ratio of the height H5 of the inlet section at lower part of the inner tube to the inner diameter Dl of the inner tube is 0.5-3: 1 with the divergence angle e of -30-30°. Three kinds of designs for diverged, equal and converged diameters may be also used to the lower end of the outer tube, in which the specific design concept is similar to the design of the pre-lifting section in a conventional catalytic cracking riser reactor.
Feed nozzle 8 of the double-pipe type of riser reactor having a single channel for feeding catalyst may be installed at lower part of the inner tube at a place 5-30% of its total length ; also, 2-4 layers of feed nozzles may be set along vertical direction of the inner tube.
Or, as shown in Figure 3, the feed nozzle may be set along central axis of the reactor so that it passes through the lower part of the outer tube and then gets into 0.1-3.0 meters in the inner tube. Feed nozzle 9 is set at a place 5-30% of the total outer tube length at the lower part of the outer tube ; also, 2-4 layers of feed nozzles may be set in vertical direction of the outer tube. Feed nozzles 8 and 9 may be used in any form favorable to disperse homogeneously hydrocarbon oil. Feed nozzles 8 or 9 can consist of 2-11 feed nozzles arranged uniformly along periphery direction. A quenching media nozzle may be set at the confluence tube in order to create conditions for injecting a quenching media. In a word, a relatively flexible feeding mode may be used, and batch feeding may be performed in the inner tube and outer tube.
The double-pipe type of riser reactor having two channels for feeding catalyst has a structure shown in Figure 4. The reactor mainly includes the following members: catalyst inlet tubes 21 and 22, inner tube 35, outer tube 36, confluence tube 38, pre-lifting distribution rings 31 and 33, and feed nozzles 32 and 34. Therein, inner tube 35 and outer tube 36 are coaxial, and the ratio of inner cross-section area of the inner tube to cross-section area of the annular space between the inner and outer tubes is 1: 0.1-10, preferably 1: 0.1-2. The catalyst inlet tube 21 is connected with the lower end of the inner tube 35 which has a, length of 10-70% of total length of the reactor, preferably 15-50%. A distance from the lower end of the outer tube 36 to the lower end of the inner tube 35 is 2-20% of total length of the reactor, preferably 5-15%. The catalyst inlet tube 22 is connected with the lower end of the outer tube 36. One end of the confluence tube 38 is connected with the upper end of the outer tube 36, and the other end is connected with a gas/solid separation apparatus. An inner cross-section area ratio of the confluence tube 38 and the inner tube 35 is 1: 0.2-0.8, preferably 1: 0.3-0.7. The pre-lifting distribution rings 31 and 33 are located at the bottom of the inner tube and the bottom of the annular space between the inner and outer tubes respectively. Feed nozzles 32 and 34 are located at the lower parts of the inner tube and the outer tube respectively. Fixing members 30 may be installed in multi-lines, for example, with 2-12 lines of shrouding wires or draw-bars between the inner and outer tubes according to specific size of the reactor and requirements of the engineering.
In the double-pipe type of riser reactor having two channels for feeding catalyst, the
distance from the upper end of the inner tube (i.e. the outlet end of the inner tube) to the outlet end of the confluence tube is 0.5-20 meters, (i.e. total length of the confluence tube) preferably 1-10 meters. It is desirable to optimize the inner diameter of the confluence tube according to the linear speed of oil-gas in the confluence tube, and the linear speed of the oil-gas in the confluence tube should be 0.5-2.0 times of the linear speed at the inner tube outlet, preferably 0.8-1.2 times. The apparent linear speed of initial lifting media vapor is 0.3-8 m/s in the inner tube, and the apparent linear speed of the lifting media vapor is 0.2-10 m/s in the outer tube.
Connection regions of the inner tube, the outer tube and the confluence tube may be used with different ways according to requirements. Figure 5 shows four modes of embodiment, which however do not intend to limit the modes used for the reactor.
As shown in Figure 5, in embodiment Al, the upper end of the inner tube is in a straight tube shape, the outer tube is also in a straight tube shape, and the confluence tube and outer tube are equal in inner diameter. The inner tube has an inner diameter of Ml, and the confluence tube has an inner diameter of M2, and M2: Ml = 1.5-5: 1.
As shown in Figure 5, in embodiment Bl, the upper outlet section of the inner tube is diverged in diameter,, the outer tube is a straight tube, and the confluence tube and outer tube are equal in inner diameter. The inner tube has an inner diameter of M1 and the confluence tube has an inner diameter of M2. The ratio of the height Nl of the upper outlet section of the inner tube to the inner diameter M1 of the inner tube is 0.5-3: 1. The divergence angle al of the upper outlet section of the inner tube is 5-30°.
As shown in Figure 5, in embodiment C1, the upper outlet section of the inner tube is diverged in diameter, and the outer tube is connected with the confluence tube after converged in diameter. The inner tube has an inner diameter of Ml and the confluence tube has an inner diameter of M2. The ratio of the height N2 of the upper outlet section of the inner tube to the inner diameter Ml of the inner tube is 0.5-3: 1. The divergence angle bl of the upper outlet section of the inner tube is 5-30°. The bottom end of the .converged section in the outer tube is located between 1.0 M2 above the inner tube outlet and 1.0M2 below the inner tube outlet with the convergence angle cl of 10-60°. The ratio of the height N 3 of the converged section of the outer tube to the inner diameter M2 of the confluence
tube is 0.5-3.0: 1.
As shown in Figure 5, in embodiment Dl the upper end of the inner tube is in a straight tube shape, and the outer tube is connected with the confluence tube after converged in diameter. The inner tube has an inner diameter as M1 and the confluence tube has an inner diameter as M2. The bottom end of the converged section of the outer tube is located between 1.0 M2 above the inner tube outlet and 1.0 M2 below the inner tube outlet with the convergence angle dl of 5-45°. The ratio of the height N4 of the converged section in the outer tube to the inner diameter M2 of the confluence tube is 0.5-3.0: 1.
The design of both lower ends of the inner tube and the outer tube in the double-pipe type of riser reactor having two channels for feeding catalyst is basically similar to that of the pre-lifting section in a conventional catalytic cracking riser reactor. The design of the pre-lifting distribution rings 31 and 33 are also basically similar to that in a conventional catalytic cracking process.
In the double-pipe type of riser reactor having two channels for feeding catalyst, the feed nozzle 32 is set at a position of 5-30% of total inner tube length along the lower part of the inner tube. Feed nozzle 34 is set at a position of 5-30%of the total outer tube length along the lower part of the outer tube. Feed nozzles 32 and 34 may be used in any form provided that it is favorable to disperse hydrocarbon oil homogeneously. Both feed nozzles 32 and 34 can consist of 2-12 feed nozzles, and said nozzles should be arranged uniformly along periphery direction.
In the processes provided in the present invention, the catalysts fed via catalyst inlet tube respectively to the inner tube and the annular reaction space between the inner and outer tubes of the double-pipe type of riser reactor may be the same or different. Specifically speaking, the catalysts fed to the inner tube and the annular reaction space between the inner and outer tubes of the double-pipe type of riser reactor may be the regenerated catalysts from a regenerator at high temperature. Also, the catalysts may be a mixture of the regenerated catalyst and an spent catalyst and/or a semi-regenerated catalyst. Or else, the regenerated catalyst may be fed to the inner tube of the double-pipe type of riser reactor, and the semi-regenerated catalyst or spent catalyst or a mixture thereof may be fed to the annular reaction space between the inner tube and outer tube, and vice versa. In a word, the catalyst
fed to the catalyst inlet tube may be contemplated comprehensively and rearranged flexibly in accordance with the unit conditions, feedstock properties and requirement for the desired products. Furthermore, the catalysts to be fed to the double-pipe type of riser reactor may also be cooled via a catalyst cooler, or may be fed to the double-pipe type of riser reactor via catalyst inlet tube after the regenerated catalyst and spent catalyst and/or semi-regenerated catalyst is fully mixed in a catalyst mixing tank.
The catalysts used in the present invention may be any catalyst suitable for catalytic cracking process, of which active components may be one, two or more selected from a group consisting of Y-type or HY-type zeolite containing or notcontaining rare earth and/or phosphor, ultra-stablility Y-type zeolite containing or notcontaining rare earth and/or phosphor, ZSM-5 series zeolite or silica-rich zeolite having a five membered ring structure, 3 -zeolite, ferrierite, and also an amorphous silica-alumina catalyst. The inner tube and the annular reaction space between the inner and outer tubes may use two different kinds of catalysts.
In the processes provided in the present invention, the bottom of the double-pipe type of riser reactor, the bottom of the inner tube and the bottom of the annular reaction space between the inner and outer tubes are furnished with an inlet of a pre-lifting media respectively. Steam, dry gas or a mixture thereof can be used as a pre-lifting media. The apparent linear speed of the pre-lifting gas in the inner tube is initially 0.3-6.0 m/s, and the apparent linear speed of the pre-lifting gas in the annular space between the inner and outer tubes is 0.2-8.0 m/s.
The hydrocarbon oil feedstocks fed to the inner tube and the annular space between the inner and outer tubes may be selected from a group consisting of: primary processing gasoline fraction, secondary processing gasoline fraction, primary processing diesel oil fraction, secondary processing diesel oil fraction, straight rungas oil, coking gas oil, deasphalted oil, hydrofined oil, hydrocracking tail oil, vacuum residuum and a mixture thereof. The hydrocarbon oil feedstock fed to the inner tube is preferably selected from a group consisting of straight run gas oil, coking gas oil, deasphalted oil, hydrofined oil, hydrocracking tail oil, vacuum residuum, atmospheric residuum and a mixture thereof. The hydrocarbon oil feedstock fed to the annular space between the inner and outer tubes is
preferably selected from a group consisting of primary processing gasoline fraction, secondary processing gasoline fraction, primary processing diesel oil fraction, or secondary processing diesel oil fraction and a mixture thereof.
The reaction conditions of the hydrocarbon oil feedstock in the inner tube are as follows : a reaction temperature of 460-580°C, preferably 480-550°C; a reaction pressure of 0.1-0.6MPa, preferably 0.2-0.4 MPa; a catalyst-oil ratio of 3-15, preferably 4-10; an oil-gas residence time of 1.0-10 seconds in the inner tube, preferably 1.5-5.0 seconds; a catalyst temperature of 620-720 °C before contacting with the hydrocarbon oil, preferably 650-700°C ; and an atomization steam amount of 1-20% by weight (based on feedstock weight), preferably 2-15% by weight.
Reaction conditions of the hydrocarbon oil feedstock in the annular space between the inner and outer tubes are as follows : a reaction temperature of 300-680°C, preferably 400-600°C ; a reaction pressure of 0.1-0.6MPa, preferably 0.2-0.4MPa; a catalyst-oil ratio of 2-30, preferably 4-20 ; an oil-gas residence time of 0.5-20 seconds, preferablyl-15 seconds; and an atomization steam amount of 1-20% by weight (based on the feedstock), preferably 1-15% by weight. The reaction conditions of the hydrocarbon oil feedstock in the annular space between the inner and outer tubes can be further optimized in the light of the properties of the hydrocarbon oil feedstock and the requirement of the desired product. When liquefied gas or lower olefins are taken as major object products, relatively severe reaction conditions can be adopted; for example, a reaction temperature of 530-680°C, a catalyst-oil ratio of 8-30, an oil-gas residence time of 5-20 seconds and the like. When gasoline and/or diesel oil are taken as major object products, relatively moderate operation conditions should be adopted, for example, a reaction temperature 3 00-540 °C, a catalyst-oil ratio of 2-8, an oil-gas residence time of 1-5 seconds, and the like.
The oil-catalyst mixtures both in the inner tube and in the annular space between the inner and outer tubes are mixed at the confluence tube inlet, and the reactfon oil-gas continues to react in the confluence tube, wherein the reaction time is 0.1-3.0 seconds, and the reaction pressure, temperature, catalyst-oil ratio and the like depond on the reaction conditions in the inner tube and the annular space. Generally, the reaction temperature is 450-600°C, the catalyst-oil ratio is 4-12, the reaction pressure is 0.1-0.6MPa, the weight ratio
of steam to the hydrocarbon oil feedstock is 0.01-0.15: 1.
The processes provided in the present invention are further illustrated as follows in combination with the Figures, but the present invention is not limited.
As shown in Figure 6, the catalyst is fed to the bottom of the double-pipe type of riser reactor having single channel for feeding catalyst via a catalyst inlet tube 1, and flows upward under an action of a pre-lifting media. A part of the catalyst flows into the inner tube 2, and the remaining part of the catalyst enters the annular reaction space between the inner tube 2 and outer tube 3, which continue to flow upward under the action of the pre-lifting media. The hydrocarbon oil feedstocks are fed via nozzles 8 and 9 to the inner tube and the annular space between the inner and outer tubes respectively to contact and react with the catalyst, and both the reaction streams continue to flow upward along vessel wall. The reaction streams both from the inner tube and from the annular space between the inner and outer tubes flow together at the inlet of the confluence tube 4, then the mixed stream enters to the settler 12 via the confluence tube and a rapid gas/solid separation apparatus, where the reaction oil-gas is separated from the reacted and carbon-deposited catalyst; then the separated reaction oil-gas enters the subsequent separation system 14 to be separated further into different products. The reacted catalyst falls down into the stripper 13, where the reaction oil-gas entrained by the catalyst is stripped off by the action of steam ; the stripped catalyst is introduced to the regenerator 15 to burn off coke for the regeneration of the catalyst. The regenerated catalyst is recycled to the reactor for reuse.
As shown in Figure 7, the catalyst is fed to the bottom of the double-pipe type of riser reactor having single channel for feeding catalyst via the catalyst inlet tube 1, and flows upward under the action of a pre-lifting media. A part of the catalyst flows into the inner tube 2, and the remaining part of the catalyst enters the annular reaction space between the inner tube 2 and outer tube 3, which continues to flow upward under the action of the pre-lifting media. The hydrocarbon oil feedstocks are fed via nozzles 8 and 9 into the inner tube and the annular space between the inner and outer tubes of the reactor respectively to contact and react with the catalyst, and the reaction streams flow upwards continuously along vessel wall. The reaction streams both from the inner tube and from the annular space between the inner and outer tubes flow together at the inlet of the confluence tube 4, and the mixed stream
enters the settler 12 via the confluence tube and a gas/solid rapid separation apparatus, where the reaction oil-gas is separated from the reacted and carbon-deposited catalyst. The separated reaction oil-gas enters the subsequent separation system 14 to be further separated into various products, and the reacted catalyst falls down into the stripper 13 where the reaction oil-gas entrained by the catalyst is stripped off under the action of steam. The stripped catalyst is fed to the regenerator 15 to burn off coke for the regeneration of the catalyst, and then the regenerated catalyst is introduced to the catalyst mixing tank 16 to mix with the spent catalyst and/or semi-regenerated catalyst. The mixed catalyst is recycled to the reactor for reuse.
As show in Figure 8, the regenerated catalyst is fed via catalyst inlet tubes 21 and 22 to the inner tube 35 and the annular reaction space between the inner tube 35 and outer tube 36 in the double-pipe type of riser reactor having two channels for feeding catalyst respectively, and flows upward under the action of pre-lifting media. The hydrocarbon oil feedstock is fed via nozzles 32 and 34 to the inner tube and the annular space between the inner and outer tubes respectively to contact and react with the catalyst, and the mixture of reaction oil-gas and the catalyst flows upward along vessel wall. The reaction streams both from the inner tube and from the annular space between the inner and outer tubes flow together at the inlet of the confluence tube 38, and the mixed stream enters the settler 12 via the confluence tube and a rapid gas/solid separation apparatus. In the settler, the reaction oil-gas is separated from the reacted and carbon-deposited catalyst. The separated reaction oil-gas enters the subsequent separation system 14 to be further separated into various products. The reacted catalyst falls down into the stripper 13 where the reaction oil-gas entrained by the catalyst is stripped off under the action of steam. The stripped catalyst is fed to the regenerator 15 to burn coke off for the regeneration of the catalyst, and then the regenerated catalyst is recycled into the reactor for reuse.
As shown in Figure 9, the regenerated catalyst is fed to the bottom of the inner tube 35 via catalyst inlet tube 21 in the double-pipe type of riser reactor and flows upward under the action of a pre-lifting media. A part of spent catalyst flows via the catalyst inlet tube 22 into the annular reaction space between the inner tube 35 and outer tube 36 and flows upward under the action of the pre-lifting media. The hydrocarbon oil feedstock is fed via nozzls
32 and 34 to the inner tube and the annular space between the inner and outer tubes respectively to contact and react with the catalyst, and the reaction mixtures of the reaction oil-gas and catalyst flow upward along vessel wall. Reaction streams both from the inner tube and from the annular space between the inner and outer tubes flow together at the inlet of the confluence tube 38, and the mixed stream enters the settler 12 via the confluence tube and a rapid gas/solid separation apparatus. In the settler, the reaction oil-gas is separated from the reacted and carbon-deposited catalyst. Then the separated reaction oil-gas enters the subsequent separation system 14 to be further separated into various products, and the reacted catalyst falls down into the stripper 13 where the reaction oil-gas entrained by catalyst is stripped off under the action of steam. The stripped spent catalyst is fed partially to the regenerator 15 to burn coke off for the regeneration of the catalyst, and the regenerated catalyst is recycled to the bottom of the inner tube for reuse. The remaining part of the spent catalyst is recycled directly to the bottom of the annular reaction space between the inner and outer tubes for reuse without regeneration.
According to the processes provided in the present invention, in addition to the flowcharts as shown in Figures 6-9 mentioned above, the regenerated catalyst, spent catalyst and semi-regenerated catalyst, or a mixture of any two thereof to be fed to the reactor can be fed via the catalyst inlet tube to the bottom of the double-pipe type of riser reactor after being cooled via a catalyst cooler.
The reactor, catalyst, feedstock oil and operation conditions used in the relaying cracking process of petroleum hydrocarbons provided in the present invention are substantially similar to those in the catalytic cracking process of petroleum hydrocarbons using the double-pipe type of riser reactor aforementioned. The difference between them lies in that: in the relaying cracking process of petroleum hydrocarbons, the hydrocarbon oil feedstock is fed only to the inner tube of the double-pipe type of riser reactor but not to the annular reaction space between the inner tube and outer tube. Thus, there exist the following differences in the aspects of the selection of feedstock and the determination of operation conditions between and the catalytic cracking process of petroleum hydrocarbon using double-pipe type of riser reactor.
The hydrocarbon oil feedstock fed into the inner tube is selected from a group
consisting of primary processing gasoline fraction, secondary processing gasoline fraction, primary processing diesel oil fraction, secondary processing diesel oil fraction, straight run gas oil, coking gas oil, deasphalted oil, hydrofined oil, hydrocracking tail oil, vacuum wax oil, vacuum residuum, atmospheric residuum and a mixture thereof. Therein, it is preferred to select from the group consisting of straight run gas oil, coking gas oil, deasphalted oil, hydrofined oil, hydrocracking tail oil, vacuum gas oil, vacuum residuum, atmospheric residuum and a mixture thereof.
The reaction of the hydrocarbon oil feedstock in the inner tube is carried out under conditions as follows: a reaction temperature of 480-700°C, preferably 500-680°C; a reaction pressure of 0.1-0.6MPa, preferably 0.2-0.4MPa; a catalyst-oil ratio of 3-30, preferably 4-25; an oil-gas residence time of 1.0-10 seconds in the inner tube, preferably 1.5-5.0 seconds; a catalyst temperature of 620-800°C before contacting with hydrocarbon oil, preferably 640-750°C; and an atomization steam amount of 1-45% by weight (based on feedstock weight), preferably 2-35% by weight.
Reaction conditions of the hydrocarbon oil feedstock in the confluence tube are as follows: a reaction temperature of 490-720°C, preferably 500-700°C ; a reaction pressure of 0.1-0.6 MPa, preferably 0.2-0.4MPa; a catalyst-oil ratio of 4-40, preferably 5-30 ; an oil-gas residence time of 0.5-10 seconds in the confluence tube, preferably 1.0-5.0 seconds; and a water-oil ratio (a weight ratio of steam to hydrocarbon oil) of 3-45% by weight (based on feedstock weight), preferably 5-35 % by weight.
The relaying cracking process of petroleum hydrocarbons is further illustrated as follows in combination with the Figures, but is not limited.
As shown in Figure 10, the regenerated catalyst is fed via the catalyst inlet tube 1 to the bottom of the double-pipe type of riser reactor having single channel for feeding catalyst, and flows upward under the action of a pre-lifting media; 20-80%by weight of catalyst flows into the inner tube 2, the remaining part of catalyst enters the annular reaction space between the inner tube 2 and outer tube 3, and both the parts of the catalyst continue to flow upward under the action of the pre-lifting media. The hydrocarbon oil feedstock is fed to the inner tube of the reactor via nozzle 8 to contact and react with the catalyst, and the reaction stream flows upward continuously along vessel wall. The reaction stream from the inner tube flows
together and react at the inlet of the confluence tube 4 with the regenerated catalyst (stream) from the annular space between the inner and outer tubes, and then the mixed reaction stream enters the settler 12 via the confluence tube and a rapid gas/solid separation apparatus, where the reaction oil-gas is separated from the reacted and carbon-deposited catalyst. The separated reaction oil-gas enters the subsequent separation system 14 to be further separated into various products, and the reacted catalyst falls down into the stripper 13 where the reaction oil-gas entrained by catalyst is striped off under the action of steam. The stripped catalyst is fed to the regenerator 15 to burn off coke for the regeneration of the catalyst, and the regenerated catalyst is recycled to the reactor for reuse.
As shown in Figure 11, the regenerated catalyst is fed via the catalyst inlet tubes 21 and 22 to the inner tube 35 and the annular reaction space between the inner tube 35 and outer tube 36 of the double-pipe type of riser reactor having two channels for feeding catalyst respectively, and flows upward under the action of a pre-lifting media. The hydrocarbon oil feedstock is fed to the inner tube of the reactor via the nozzle 32 to contact and react with the catalyst, and the mixture of the reaction oil-gas and the catalyst flows upward along vessel wall. The reaction stream from the inner tube flows together and reacts at the inlet of the confluence tube 38 with the regenerated catalyst (stream) from the annular reaction space between the inner tube 35 and outer tube 36. Then the mixed stream enters the settler 12 via the confluence tube and a rapid gas/solid separation apparatus. In the settler, the reaction oil-gas and the reacted and carbon-deposited catalyst are separated. The separated reaction oil-gas enters the subsequent separation system 14 to be further separated into various products. The reacted catalyst falls down into the stripper 13 where the reaction oil-gas entrained by catalyst is stripped off under the action of steam. The stripped catalyst is introduced to the regenerator 15 to burn off coke for the regeneration of the catalyst, and the regenerated catalyst is recycled to the reactor for reuse.
In addition to those shown in Figures 10 and 11 aforementioned,' in the relaying cracking process of petroleum hydrocarbon, the regenerated catalyst to be fed to the reactor can be fed to the bottom of the double-pipe type of riser reactor after being cooled via a catalyst cooler.
The following examples further illustrate but do not intend to limit the processes
provided in the present invention.
The catalyst used in the examples is a commercial product from Catalyst Plant, Lan Zhou Petroleum Refining & Chemical General Factory, Trademark LV-23, of which major properties are shown in Table 1. The hydrocarbon oil feedstock used in the Examples is Da Qing VGO added with 30% by weight of VR, of which properties are shown in Table 2. The testing apparatus used in the Examples is a double-pipe type of micro-riser cracker unit.
Example 1
The present example shows test results obtained, by using the process provided in the present invention when light oil is produced as main object product.
Main steps of the test are as follows. The feedstock oil shown in Table 1 and the recycled oil of the present unit were mixed, the mixed oil was heated via a preheating furnace and fed to the inner tube of the double-pipe type of riser reactor to contact and react with the regenerated catalyst flowing from the regeneration sloped tube and lifted with a pre-lifting media. The cracking gas produced in the present unit was fed to the annular reaction space between the inner and outer tubes to contact and react with the regenerated catalyst therein. The oil-catalyst mixture in the inner tube and the oil-catalyst mixture in the annular reaction space moved up along vessel wall respectively, then mixed with each other at the confluence tube inlet to continue the reaction, and then entered a settler. In the settler, the reaction oil-gas was separated from the reacted catalyst, then entered a subsequent fractionation system via an oil-gas pipeline to be further fractionated into various products. The formed products were metered and analyzed respectively. Spent catalyst was stripped with steam, then introduced into a regenerator to burn off coke for the regeneration of the catalyst. The regenerated catalyst was recycled to the reactor for reuse.
Main operation conditions, product distribution and main product properties are shown in Tables 3, 4 and 5 respectively. It can be seen from Tables 4 and 5 that when light oil is produced as main object product, the yield of gasoline+diesel oil can amount to 77.80% by weight and a total yield of liquid products can amount to 89.96%by weight with a lower yield of dry gas and coke of the process of the present invention.
Example 2
The present example shows test results obtained by using the process provided in the
present invention when a liquefied gas is produced as main object product.
Main steps of the test are as follows. The feedstock oil shown in Table 1 was heated via a preheating furnace, then fed to the inner tube of the double-pipe type of riser reactor to contact and react with the regenerated catalyst flowing from the regeneration sloped tube and lifted with a pre-lifting media. The light oil (gasoline+diesel oil) with a distillation range less than 350°C produced in the present unit was fed into the annular reaction space between the inner and outer tubes to contact and react with the regenerated catalyst therein. Both the oil-catalyst mixture from the inner tube and the oil-catalyst mixture from the annular reaction space moved up along vessel wall respectively, mixed with each other at the confluence tube inlet to continue the reaction, and then entered a settler. In the settler, the reaction oil-gas was separated from the reacted catalyst, then entered a subsequent fractionation system via an oil-gas pipeline to be further fractionated into various products. The formed products were metered and analyzed respectively. The spent catalyst was stripped with steam, and then introduced to a regenerator to burn off coke for the regeneration of the catalyst. The regenerated catalyst was recycled to the reactor for reuse.
The main operation conditions are shown in Table 3, the product distribution is shown in Table 4, and the main product properties are shown in Table 5. It can be seen from Tables 4 and 5 that when liquefied gas is produced as main object product , the yield of liquefied gas can amount to 29.46 % by weight and the total yield of liquid products can amount to 89.65 %by weight with a lower yield of dry gas and coke of the process of the present invention.
Example 3
The present example shows test results obtained by using the process provided in the present invention when gasoline is produced as main object product.
The main steps of the test are as follows. The feedstock oil shown in Table 1 and the recycled oil produced in the present unit were mixed, then the mixed oil was heated via a preheating furnace and fed to the inner tube of the double-pipe type of riser reactor to contact and react with the regenerated catalyst flowing from the regeneration sloped tube and lifted with a pre-lifting media. Coking gasoline feedstock (with a density of 0.7316 g /cm3, RON = 58.8, MON = 65.4, an olefin content of 37.49%by weight) was fed to the annular reaction
space between the inner and outer tubes to contact and react with the regenerated catalyst therein. Both the oil-catalyst mixture in the inner tube and the oil-catalyst mixture in the annular reaction space moved up along vessel wall respectively, mixed with each other at the confluence tube inlet to continue the reaction, and then entered a settler. In the settler, the reaction oil-gas was separated from the reacted catalyst, and then entered a subsequent fractionation system via an oil-gas pipeline to be further fractionated into various products. The formed products were metered and analyzed respectively. The spent catalyst was stripped with steam, then introduced to a regenerator to burn off coke for the regeneration of the catalyst. The regenerated catalyst was recycled to the reactor for reuse.
Main operation conditions, product distribution and main product properties are shown in Tables 3, 4 and 5 respectively. It can be seen from Tables 4 and 5 that when gasoline is produced as main object product, the gasoline yield can amount to 59.49%by weight, the yield of light oil is 78.14%by weight, and total yield of liquid products amounted to 90.00% by weight with a lower yield of dry gas and coke of the process of the present invention meanwhile, a good quality of gasoline product is obtained.
Example 4
The present example shows test results obtained by using the process provided in the present invention when diesel oil is produced as main object product.
Main teps of test are as follows. As shown in Figure 3, the feedstock oil shown in Table 1 was mixed with the recycled oil of the present unit, the mixed oil was heated via a preheating furnace and fed to the inner tube of the double-pipe type of riser reactor to contact and react with the mixed catalyst from catalyst mixing tank 16 in which the regenerated catalyst and the spent catalyst were mixed. The coking diesel oil feedstock (with a density of 0.8520 g/cm3, a sulfur content of 8225ppm, and a nitrogen content of 5018ppm, a cetane number of 47) was fed to the annular reaction space between the inner and outer tubes to contact and react with the catalyst therein. Both the oil-catalyst mixture in the inner tube and the oil-catalyst mixture in the annular reaction space moved up along vessel wall respectively, then mixed with each other at the confluence tube inlet to continue the reaction, and then entered a settler. In the settler, the reaction oil-gas was separated from the reacted catalyst, and then entered a subsequent fractionation system via an oil-gas pipeline to be
further fractionated into various products. The formed products were metered and analyzed respectively. The spent catalyst was stripped with steam, then part of the stripped catalyst was introduced into a regenerator to burn off coke for the regeneration of the catalyst, and the remaining part of the spent catalyst was fed directly into the catalyst mixing tank 16 to mix with the regenerated catalyst in a mixing ratio of the regenerated catalyst to the spent catalyst of 2: 1. Then the mixed catalyst was recycled to the reactor for reuse.
Main operation conditions, product distribution and main product properties are shown in Tables 3, 4 and 5 respectively. It can be seen from Tables 4 and 5 that when diesel oil is produced as main object product, the yield of diesel oil can amount to 35.13% by weight and the total yield of liquid products can amount to 89.93 %by weight with a lower yield of dry gas and coke in the process of the present invention:
Example 5
The present example shows test results obtained by using the process provided in the present invention when liquefied gas and diesel oil are produced as main object products.
The main steps of test are as follows: The feedstock oil shown in Table 1 was mixed with the recycled oil from the present unit, and the mixed oil was heated via a preheating furnace and then fed to the inner tube of the double-pipe type of riser reactor to contact and react with the regenerated catalyst flowing from regeneration sloped tube and lifted with a pre-lifting media. The gasoline fraction produced in the present unit was fed to the annular reaction space between the inner and outer tubes to contact and react with the regenerated catalyst therein. Both the oil-catalyst mixture in the inner tube and the oil-catalyst mixture in the annular reaction space moved up along vessel wall respectively, mixed each other at the confluence tube inlet to continue the reaction, and then entered a settler. In the settler, the reaction oil-gas was separated from the reacted catalyst, and entered a subsequent fractionation system via an oil-gas pipeline to be further fractionated into various products. The formed products were metered and analyzed respectively. The spent catalyst was stripped with steam, and then introduced to a regenerator to burn off coke for the regeneration of the catalyst. The regenerated catalyst was recycled to the reactor for reuse.
Main operation conditions, product distribution and main product properties are shown in Tables 3, 4 and 5 respectively. It can be seen from Tables 4 and 5 that when liquefied gas

and diesel oil are produced as main object products, the yield of liquefied gas can amount to 19.08% by weight, the yield of diesel oil can amount to 31.46% by weight, and the total yield of liquid products can amount to 88.80%by weight with a lower yield of dry gas and coke of the process of the present invention.
In the following examples, the relaying cracking process will be further illustrated but not limited. The catalysts used in the examples below were commercial products with trademarks respectively of RMQ CIP-1 and CEP manufactured by Qi Lu Petrochemical Catalyst Factory, and the three kinds of catalysts were hydrothermally aged, of which the main properties are shown in Table 6. In the examples, the hydrocarbon oil feedstock used is Da Qing VGO added with 30% by weight of VR, of which properties are shown in Table 1, and the testing apparatus used in the examples below was a small double-pipe type
catalytic cracking apparatus.
Example 6
The present example illustrates that higher yields of liquefied gas, gasoline and diesel oil can be obtained by using the relaying cracking process provided in the present invention with heavy petroleum hydrocarbon as feedstock.
The steps for test are mainly as follows. As shown in Figure 10, the regenerated catalyst was introduced into the bottom of the double-pipe type of riser reactor via the catalyst inlet tube 1, and flew upward under the action of a pre-lifting vapor with 70% by weight of the catalyst flew into the inner tube 2 and the remaining 30% by weight of catalyst entered into the annular reaction space between the inner tube 2 and outer tube 3 to continue flowing upward under the action of pre-lifting vapor. The hydrocarbon oil feedstock as shown in Table 1 was preheated, and fed to the inner tube via the nozzles 8 to contact and react with the catalyst; the reaction stream flew upward continuously along vessel wall. The mixture of the reaction oil-gas and catalyst from the inner tube flew together and reacted at the inlet of the confluence tube 4 with the regenerated catalyst stream from the annular space between the inner tube 2 and outer tube 3, and the mixed stream flew through the confluence tube and a rapid gas/solid separation apparatuo into the settler 12, where the reaction oil-gas was separated from the reacted and carbon-deposited catalyst. The separated reaction oil-gas entered the subsequent separation system 14 to be further separated into various products.
The reacted catalyst fell down into the stripper 13 where the reaction oil-gas entrained by catalyst was stripped off under the action of steam, and the stripped catalyst was introduced to the regenerator 15 to burn coke off for the regeneration of the catalyst. The regenerated catalyst was recycled to the reactor for reuse.
Both main operation conditions and product distribution are shown in Table 7. From Table 7, it can be seen that the present invention has a total liquid yield of light hydrocarbons (liquefied gas + gasoline + diesel oil) of 86.62 %by weight with a lower yield of dry gas and coke.
Example 7
The present example illustrates that a higher yield of lower olefins such as propylene and the like can be obtained by using the relaying cracking process of the present invention when a heavy petroleum hydrocarbon is used as feedstock.
Main steps of test are as follows. As shown in Figure 11, the regenerated catalyst was fed via the catalyst inlet tubes 21 and 22 to the inner tube 35 and the annular reaction space between the inner tube 35 and the outer tube 36 of the double-pipe type of riser reactor having two channels for feeding catalyst respectively, and both parts of the regenerated catalyst flew upward under the action of pre-lifting media. The catalyst fed to the inner tube was 40% by weight of the total catalyst weight. The catalyst fed to the annular space was 60% by weight of the total catalyst weight. The hydrocarbon oil feedstock was fed to the inner tube of the reactor via the nozzle 32 to contact and react with the catalyst, and the mixture of the reaction oil-gas and the catalyst flew upward along vessel wall. The reaction stream from the inner tube flew together and reacted at the inlet of the confluence tube 38 with the regenerated catalyst stream from the annular reaction space between the inner tube 35 and the outer tube 36, and then the mixed stream entered the settler 12 via a confluence tube and a rapid gas/solid separation apparatus. In the settler, the reaction oil-gas is separated from the reacted and carbon-deposited catalyst. The separated reaction oil-gas entered the subsequent separation system 14 to be further separated into various products. The reacted catalyst fell down into the stripper 13 where the reaction oil-gas entrained by catalyst was stripped off under the action of steam. The stripped catalyst was introduced to the regenerator 15 to burn coke off for the regeneration of the catalyst. The regenerated
catalyst was recycled to the reactor for reuse.
Both main operation conditions and product distribution are shown in Table 7. From Table 7, it can be seen that when lower olefins consisting mainly of propylene is produced as main object product, the yields of ethylene, propylene and butylene can amount to 4.79%, 24.01 % and 15.28% by weight, respectively with a lower yield of dry gas and coke of the process of the present invention.
Example 8
This example illustrates that higher yield of lower olefins such as ethylene and the like can be obtained by using the relaying cracking process of the present invention with a heavy petroleum hydrocarbon as feedstock.
Main steps of test are as follows. As shown in Figure 11, the regenerated catalyst was fed via the catalyst inlet tubes 21 and 22 to the inner tube 35 and the annular reaction space between the inner tube 35 and the outer tube 36 of the double-pipe type of riser reactor having two channels for feeding catalyst respectively, and both parts of the regenerated catalyst flew upward under the action of a pre-lifting media. The catalyst fed to the inner tube was in an amount of 50% of the total catalyst weight, and the catalyst fed to the annular space was also in an amount of 50% of the total catalyst weight. The hydrocarbon oil feedstock was fed to the inner tube of the reactor via the nozzle 32 to contact and react with the catalyst, and the mixture of the reaction oil-gas and the catalyst flew upward along vessel wall. The reaction stream from the inner tube flew together and reacted at the confluence tube inlet 38 with the regenerated catalyst stream from the annular reaction space between the inner tube 35 and the outer tube 36, and then entered the settler 12 via the confluence tube and a rapid gas/solid separation apparatus. In the settler, the reaction oil-gas was separated from the reacted and carbon-deposited catalyst. The separated reaction oil-gas flew into the subsequent separation system 14 to be further separated into various products. The reacted catalyst fell down into the stripper 13 where the reaction oil-gas entrained by catalyst was stripped off under the action of steam. The stripped catalyst was introduced to the regenerator 15 to burn coke off for the regeneration of the catalyst. The regenerated catalyst was recycled to the reactor for reuse.
Both main operation conditions and product distribution are shown in Table 7. From
Table 7, it can be seen that, the yields of ethylene, propylene and butylene can amount to 27.63%, 17.62% and 5.06% by weight, respectively, when lower olefins consisting mainly of ethylene is produced as main object product by using the process of the present invention.
Comparative Example
In the comparative example, a conventional riser reactor was used, and the same feedstock oil, catalyst and operation conditions were used as those used in Example 6.
Main steps of test are as follows. The preheated feedstock oil, was fed to the riser reactor to contact and react with the regenerated catalyst flowing from the regeneration sloped tube and lifted with pre-lifting media. The formed reaction oil-gas flew into a settler via a riser; in the settler, the reaction oil-gas was separated from the reacted catalyst. Then, the separated oil-gas entered into a subsequent fractionation system via oil-gas pipeline to be further fractionated into various products. The formed products were metered and analyzed respectively. The spent catalyst was stripped with steam, then introduced to a regenerator to burn off coke for the regeneration of the catalyst. The regenerated catalyst was recycled into to the reactor for reuse.
Both main operation conditions and product distribution are shown in Table 7. Comparing Example 6 with the comparative example, it can be seen that the process of the present invention has a relatively strong ability to convert heavy oils and desired product selectivity.

(Table Removed)
Note *: Yield of light oils = gasoline yield + diesel yield
Total liquid Yield of light hydrocarbons = liquefied gas yield + gasoline yield + diesel yield
Table 5

Table 6

(Table Removed)
Note: *refers to pyrolysis activity index
Table 7
(Table Removed)
Note*: Total liquid Yield of light hydrocarbons = liquefied gas yield + gasoline yield + diesel
yield







We claim:
1. A catalytic cracking process of petroleum hydrocarbons, comprising the following steps:
(1) feeding a catalyst from a inlet tube to an inner tube and an annular reaction space between inner and outer tubes of a double-pipe type of riser reactor, and flowing upward under an action of pre-lifting media;
(2) feeding a hydrocarbon oil feedstock into the inner tube and the annular space between the inner and outer tubes of the reactor, which contacts with the catalyst therein to form an oil-catalyst mixture, so that the reaction of the hydrocarbon oil feedstock is carried out under catalytic cracking reaction conditions, and the reaction streams including the reaction oil-gas and catalyst flow upward along vessel wall.
(3) the reaction streams both from the inner tube and from the annular space between the inner and outer tubes flow together at the inlet of a confluence tube, and the mixed stream enters a separation apparatus via the confluence tube, where the reaction oil-gas is separated from the reacted and carbon-deposited catalyst ;
(4) further separating the reaction oil-gas into various products including gasoline, diesel oil and liquefied gas, stripping and regenerating the reacted and carbon-deposited catalyst, and recycling the regenerated catalyst into the reactor for reuse.
2. The process as claimed in claim 1, wherein said hydrocarbon oil feedstocks fed into the
inner tube and the annular space between the inner and outer tubes can be selected from a group
consisting of primary processing gasoline fraction, secondary processing gasoline fraction, primary
processing diesel oil fraction, secondary processing diesel oil fraction, straight run gas oil, cooking
gas oil, deasphalted oil, hydrofined oil, hydrocracking tail oil, vacuum gas oil, vacuum residuum, or
atmospheric residuum and a mixture thereof.
3. The process as claimed in claim 2, wherein said hydrocarbon oil feedstock fed into the inner tube is selected from a group consisting of straight run gas oil, cooking gas oil, deasphalted oil, hydrofined oil, hydrocracking tail oil, vacuum gas oil, vacuum residuum or atmospheric residuum and a mixture thereof; and the hydrocarbon oil feedstock fed to the annular reaction space between the inner and outer tubes is selected from the a consisting of primary processing gasoline fraction, secondary processing gasoline fraction, primary processing diesel oil fraction, secondary processing diesel oil fraction and a mixture thereof.
4. The process as claimed in claim 1, wherein said hydrocarbon oil feedstock is reacted in the inner tube under conditions as follows: a reaction temperature of 460-580□, a reaction pressure of 0.1-0.6MPa, a catalyst-oil ratio of 3-15, an oil-gas residence time of 1.0-10 seconds in the inner tube, a catalyst temperature of 620-720 □ before contacting with the hydrocarbon oil, and an atomization steam amount of 1-20% by weight.
5. The process as claimed in claim 4, wherein said hydrocarbon oil feedstock is reacted in the inner tube under conditions as follows: a reaction temperature of 480-550D, a reaction pressure of 0.2-0.4MPa, a catalyst-oil ratio of 4-10, an oil-gas residence time of 1.5-5.0 seconds in the inner tube, a catalyst temperature of 650-700□ before contacting with the hydrocarbon oil, and an atomization steam amount of 2-15% by weight.
6. The process as claimed in claim 1, wherein said hydrocarbon oil feedstock is reacted in the annular space between the inner and outer tubes under conditions as follows: a reaction temperature of 300-680□, a reaction pressure of 0.1-0.6MPa, a catalyst-oil ratio of 2-30, an oil-gas residence time of 0.5-20 seconds, and an atomization steam amount of 1-20%by weight.
7. The process as claimed in claim 6, wherein said hydrocarbon oil feedstock is reacted in the annular space between the inner and outer tubes under conditions as follows: a reaction temperature of 400-600□, a reaction pressure of 0.2-0.4MPa, a catalyst-oil ratio of 4-20, an oil-gas residence time of 1-15 seconds, and an atomization steam amount of 1-15% by weight.
8. The process as claimed in claim 1, wherein said catalyst fed via catalyst inlet tube to the inner tube and the annular reaction space between the inner and outer tubes of the double-pipe type of riser reactor is selected from a group consisting of: a regenerated catalyst, a semi-regenerated catalyst, a spent catalyst and a mixture thereof, and the carbon content of the catalyst fed to the inner tube may be different from that of the catalyst fed to the annular reaction space between the inner tube and outer tube.
9. The process as claimed in claim 1, wherein said double-pipe type of riser reactor is one having single channel for feeding catalyst, which comprises mainly the following members: catalyst inlet tube (1), inner tube (2), outer tube (3), confluence tube (4), pre-lifting distribution rings (5), (6) and (7) and feed nozzles (8) and (9); wherein inner tube (2) and outer tube (3) are coaxial, and the ratio of the inner cross-section area of the inner tube to the cross-section area of the annular space between the inner and outer tubes is 1: 0.1-10; the lower end of the inner tube (2) is located at a place above the catalyst inlet, the inner tube has a length amounting to 10-70% of the total length of the reactor ; one end of the confluence tube (4) is connected with the upper end of the outer tube (3), and the other end is connected with a gas/solid separation apparatus, the cross-section area ratio of the confluence tube (4) to the inner tube (2) is 1: 0.2-0.8; the pre-lifting distribution rings (5), (6) and (7) are respectively located at the bottoms of the reactor, the inner tube and the outer tube.
10. The process as claimed in claim 9, characterized in that the ratio of intermediate cross-
section area of the inner tube to the cross-section area of the annular space between the inner and
outer tubes in said double-pipe type of riser reactor is 1: 0.2-2.
11. The process as claimed in claim 9, characterized in that the inner tube of said double-pipe type of riser reactor has a length amounting to 20-60% of the total length of the reactor.
12. The process as claimed in claim 9, characterized in that said double-pipe type of riser reactor has a distance of 1-30 meters from the outlet end of the inner tube to the outlet end of the confluence tube.
13. The process as claimed in claim 9, characterized in that said double-pipe type of riser reactor is installed with 2-12 lines of shrouding wires or draw-bars between the inner tube and the outer tube.
14. The process as claimed in claim 1, wherein said double-pipe type of riser reactor is one
having two channels for feeding catalyst, and comprises mainly the following members: catalyst inlet
tubes (21) and (22), inner tube (35), outer tube (36), confluence tube (38), pre-lifting distribution
rings (31) and (33), and feed nozzles (32) and (34), wherein the inner tube (35) and outer tube (36)
are coaxial; the ratio of the inner cross-section area of the inner tube to the cross-section area of the
annular space between the inner and outer tubes is 1: 0.1-10; the catalyst inlet tube (21) is connected
with the lower end of the inner tube (35), the length of the inner tube is 10-70% of the total length of
the reactor ; the distance from the lower end of the outer tube (36) to the lower end of the inner tube
(35) is 2-20% of the total length of the reactor ; the catalyst inlet tube (22) is connected with the
lower end of the outer tube (36) ; one end of the confluence tube (38) is connected with the upper
end of the outer tube (36) and the other end is connected with a gas/solid separation apparatus, the
inner cross-section area ratio of the confluence tube (38) to the inner tube (35) is 1: 0.2-0.8, the pre-
lifting distribution rings (31) and (33) are located at the bottom of the inner tube and the bottom of
the annular space between the inner tube and outer tube respectively, and feed nozzles (32) and (34)
are located at the lower parts of the inner tube and the outer tube respectively .
15. The process as claimed in claim 14, characterized in that the ratio of the inner cross-section area of the inner tube to the cross-section area of the annular space between the inner and outer tubes is 1: 0.1-2 in said double-pipe type of riser reactor.
16. The process as claimed in claim 14, characterized in that said double-pipe type of riser reactor has an inner tube with a length amounting to 15-50% of the total length of the riser reactor.
17. The process as claimed in claim 14, characterized in that the distance from the lower end of the outer tube to the lower end of the inner tube in said double-pipe type of riser reactor is 5-15% of the total length of the riser reactor.
18. The process as claimed in claim 14, characterized in that the inner cross-section area ratio of the confluence tube to the inner tube is 1: 0.3-0.7 in said double-pipe type of riser reactor.
19. The process as claimed in claim 14, characterized in that said double-pipe type of riser reactor is installed with 2-12 lines of shrouding wires or draw-bars between the inner tube and the outer tube.
20. The process as claimed in claim 14, characterized in that said double-pipe type of riser reactor has a distance of 0.5-20 meters from the outlet end of the inner tube to the outlet end of the confluence tube.
21. A catalytic cracking process of petroleum hydrocarbons as claimed in claim 1, comprising mainly the following steps:

(1) feeding a regenerated catalyst to the bottom of the double-pipe type of riser reactor via the catalyst inlet tube, which flows upwards under an action of a pre-lifting media, 20-80%by weight of the regenerated catalyst flowing into the inner tube, and the remaining part of the catalyst entering the annular reaction space between the inner and outer tubes, which flows upward under an action of the pre-lifting media ;
(2) feeding a hydrocarbon oil feedstock in to the inner tube of the reactor to contact with the catalyst therein and form a oil-catalyst mixture, so that the reaction of the hydrocarbon oil feedstock is carried out under catalytic cracking reaction conditions, wherein the reaction stream, including the reaction oil-gas and the catalyst flows upward along vessel wall;

(3) the reaction stream from the inner tube and the regenerated catalyst (stream) from the annular reaction space flow together at the confluence tube inlet of the reactor, and making the reaction oil-gas react continuously under catalytic cracking conditions; introducing the formed reaction stream to a separation apparatus via the confluence tube, where the reaction oil-gas is separated from the reacted and carbon-deposited catalyst;
(4) separating the reaction oil-gas further into various products including gasoline, diesel oil and liquefied gas; stripping and regenerating the reacted catalyst, and recycling the regenerated catalyst into the reactor for reuse.

22. The process as claimed in claim 21, wherein said catalyst fed to the double-pipe type of riser reactor via the catalyst inlet tube is a regenerated catalyst or a cooled and regenerated catalyst.
23. The process as claimed in claim 21 or 22, wherein active components of said catalyst are one, or two or more selected from a group consisting of Y-type or HY-type zeolite containing or not containing rare earth and/or phosphor, ultrastability Y-type zeolite containing or not containing rare earth and/or phosphor, ZSM-5 series zeolite or silica-rich zeolite having a five-membered ring structure, ß-zeolite, or ferrierite.
24. The process as claimed in claim 21, wherein said catalyst contains 0.5-60%by weight of ZSM-5 series zeolite or other silica-rich zeolite having a five-membered ring structure .
25. The process as claimed in claim 21, wherein said hydrocarbon oil feedstock fed to the inner tube is selected from a group consisting of: primary processing gasoline fraction, secondary processing gasoline fraction, primary processing diesel oil fraction, secondary processing diesel oil fraction, straight run gas oil, cooking gas oil, deasphalted oil, hydrofined oil, hydrocracking tail oil, vacuum gas oil, vacuum residuum or atmospheric residuum and a mixture thereof.
26. The process as claimed in claim 25, wherein said hydrocarbon oil feedstock fed to the inner tube is selected from the group consisting of straight run gas oil , cooking gas oil, deasphalted oil, hydrofined oil, hydrocracking tail oil, vacuum gas oil , vacuum residuum, or atmospheric residuum and a mixture thereof.
27. The process as claimed in claim 21, wherein said hydrocarbon oil feedstock is reacted in the inner tube under conditions as follows: a reaction temperature of 480-700□, a reaction pressure of 0.1-0.6MPa, a catalyst-oil ratio of 3-30, an oil-gas residence time of 1.0-10 seconds in the inner tube, a catalyst temperature of 620-800□ before contacting with the hydrocarbon oil, and an atomization steam amount of 1-45% by weight.
28. The process as claimed in claim 27, wherein said hydrocarbon oil feedstock is reacted in the inner tube under conditions as follows: a reaction temperature of 500-680 □, a reaction pressure of 0.2-0.4MPa, a catalyst-oil ratio of 4-25, an oil-gas residence time of 1.5-5.0 seconds in the inner tube, a catalyst temperature of 640-750□ before contacting with the hydrocarbon oil, and an atomization steam amount of 2-35% by weight.
29. The process as claimed in claim 21, wherein said hydrocarbon oil feedstock is reacted in the confluence tube under conditions as follows: a reaction temperature of 490-720□, a reaction pressure of 0.1-0.6MPa, a catalyst-oil ratio of 4-40, an oil-gas residence time of 0.5-10 second in the confluence tube, and a steam/feedstock ratio of 3-45 by %weight.
30. The process as claimed in claim 29, wherein said hydrocarbon oil feedstock is reacted in the confluence tube under conditions as follws: a reaction temperature of 500-700□, a reaction pressure of 0.2-0.4MPa, a catalyst-oil ratio of 5-30, an oil-gas residence time of 1.0-5 seconds in the confluence tube, and a steam/feedstock ratio of 5-35% by weight.
31. The process as claimed in claim 21, wherein said double-pipe type of riser reactor is one having single channel for feeding catalyst and comprises mainly the following members: catalyst inlet tube (1), inner tube (2), outer tube (3), confluence tube (4), pre-lifting distribution rings (5), (6) and (7), and feed nozzles (8) and (9), wherein, the inner tube (2) and the outer tube (3) are coaxial, and the ratio of the inner cross-section area of the inner tube to the cross-section area of the annular space between the inner and outer tubes is in the range 1: 0.1-10; the lower end of the inner tube (2) is located at a place above the catalyst inlet, the inner tube has a length amounting to 10-70% of the total length of the reactor ; one end of the confluence tube (4) is connected with the upper end of the outer tube (3), and the
other end is connected to the gas/solid separation apparatus, the cross-section area ratio of the confluence tube (4) to the inner tube (2) is 1: 0.2-0.8 ; the pre-lifting distribution rings (5), (6) and (7) are located at the bottoms of the reactor, the inner tube and the outer tube respectively.
32. The process as claimed in claim 31, characterized in that said double-pipe type of riser reactor has a ratio of the inner cross-section area of the inner tube to the cross-section area of the annular space between the inner and outer tubes in a range of 1: 0.2-2.
33. The process as claimed in claim 31, characterized in that the inner tube of said double-pipe type of riser reactor has a length amounting to 20-60% of the total length of the reactor.
34. The process as claimed in claim 31, characterized in that said double-pipe type of riser reactor has a distance of 1-30 meters from the outlet end of the inner tube outlet end of the confluence tube.
35. The process as claimed in claim 31, characterized in that said double-pipe type of riser reactor is installed with 2-12 lines of shrouding wires or draw-bars between the inner tube and outer tube.

36. The process as claimed in claim 21, wherein said double-pipe type of riser reactor is one
having two channels for feeding catalyst and comprises mainly the following members: catalyst inlet
tubes (21) and (22), inner tube (35), outer tube (36), confluence tube (38), pre-lifting distribution
rings (31) and (33), and feed nozzles (32) and (34), wherein, the inner tube (35) and outer tube (36)
are coaxial, the ratio of the inner cross-section area of the inner tube to the cross-section area of the
annular space between the inner and outer tubes is 1: 0.1-10; the catalyst inlet tube (21) is connected
with the lower end of the inner tube (35), the length of the inner tube is 10-70% of the total length of
the reactor; the distance from the lower end of the outer tube (36) to the lower end of the inner tube
(35) is 2-20% of the total length of the reactor, the catalyst inlet tube (22) is connected with the
lower end of the outer tube (36) ; one end of the confluence tube (38) is connected with the upper
end of the outer tube (36), and the other end is connected with a gas/solid separation apparatus, the
inner cross-section area ratio of the confluence tube (38) to the inner tube (35) is 1: 0.2-0.8 ; the
pre-lifting distribution rings (31) and (33) are located at the bottom of the inner tube and the bottom
of the annular space between the inner and outer tubes respectively ; feed nozzles (32) and (34) are
located at the lower part of the inner tube and the lower part of the outer tube respectively.
37. The process as claimed in claim 36, characterized in that said double-pipe type of riser
reactor has a ratio of the inner cross-section area of the inner tube to the cross-section area of the
annular space between the inner and outer tubes in a range of 1: 0.1-2.
38. The process as claimed in claim 36, characterized in that inner tube of said double-pipe type of riser reactor has a length amounting to 15-50% of the total length of the riser reactor.
39. The process as claimed in claim 36, characterized in that said double-pipe type of riser reactor has a distance of 5-15% of the total length of the riser reactor from a lower end of the outer tube to the lower end of the inner tube.
40. The process as claimed in claim 36, characterized in that said double-pipe type of riser reactor has an inner cross-section area ratio of the confluence tube to the inner tube in a range of 1: 0.3-0.7.
41. The process as claimed in claim 36, characterized in that said double-pipe type of riser reactor is installed with 2-12 lines of shrouding wires or draw-bars between the inner tube and outer tube.
42. The process as claimed in claim 36, characterized in that said double-pipe type of riser
reactor has a distance of 0.5-10 meters from the outlet end of the inner tube to the outlet end of the
confluence tube.
43. A catalytic cracking process of petroleum hydrocarbons substantially as herein described
with reference to the foregoing examples.

Documents:

861-del-2002-1-Correspondence Others-(19-02-2013).pdf

861-DEL-2002-Abstract-(30-04-2010).pdf

861-del-2002-abstract.pdf

861-del-2002-Claims-(19-03-2013).pdf

861-DEL-2002-Claims-(30-04-2010).pdf

861-del-2002-claims.pdf

861-del-2002-Correspondence Others-(19-02-2013).pdf

861-del-2002-Correspondence Others-(19-07-2012).pdf

861-DEL-2002-Correspondence-Others-(13-03-2013).pdf

861-del-2002-Correspondence-Others-(19-03-2013).pdf

861-DEL-2002-Correspondence-Others-(30-04-2010).pdf

861-del-2002-correspondence-others.pdf

861-del-2002-correspondence-po.pdf

861-DEL-2002-Description (Complete)-(30-04-2010).pdf

861-del-2002-description (complete).pdf

861-del-2002-drawings.pdf

861-del-2002-form-1.pdf

861-del-2002-form-18.pdf

861-del-2002-form-2.pdf

861-del-2002-Form-3-(19-07-2012).pdf

861-DEL-2002-Form-3-(30-04-2010).pdf

861-del-2002-form-3.pdf

861-del-2002-form-5.pdf

861-DEL-2002-GPA-(13-03-2013).pdf

861-del-2002-gpa.pdf

861-DEL-2002-Petition-137-(30-04-2010).pdf

861-DEL-2002-Petition-138-(30-04-2010).pdf

861-del-2002-petition-138.pdf


Patent Number 257520
Indian Patent Application Number 861/DEL/2002
PG Journal Number 42/2013
Publication Date 18-Oct-2013
Grant Date 10-Oct-2013
Date of Filing 23-Aug-2002
Name of Patentee CHINA PETROLEUM & CHEMICAL CORPORATION
Applicant Address 6A HUIXIN DONG STREET, CHAOYANG DISTRICT, BEIJING 100029, P.R.CHINA.
Inventors:
# Inventor's Name Inventor's Address
1 ZHANG RUICHI, ZHONG XIAOXIANG, ZHANG JIUSHUM, XU KEJIA, ZHANG ZHIGANG, HOU SHUANDI, CHANG XUELIANG AND WU ZHIGUO 18 XUEYUAN ROAD, HAIDIAN DISTRICT, BEIJING 100083, P.R.CHINA.
PCT International Classification Number C10G 11/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 01134268.4 2001-10-30 China
2 01258820.2 2001-08-29 China
3 01134269.2 2001-10-30 China
4 01141477.4 2001-09-27 China
5 01264042.5 2001-09-27 China