KR102136853B1 - Integrated solvent deasphalting and steam pyrolysis process for direct processing of a crude oil - Google Patents

Abstract

A process is provided for a steam pyrolysis zone integrated with a solvent deasphalting zone for direct processing of crude oil feedstock to produce petrochemicals containing olefins and aromatics. Integrated solvent deasphalting and steam pyrolysis processes for the direct processing of crude oil for the production of olefins and aromatic petrochemicals are effective amounts of solvents for deasphalting and demetallising oil streams and for the production of lower asphalt phases. And filling with a solvent deasphalting zone; Thermal cracking the deasphalted and demetallized oil stream in the presence of steam to produce a mixed product stream; Separating the mixed product stream; Recovering olefins and aromatics from the separated mixed product stream; And recovering pyrolysis fuel oil from the separated mixed product stream.

Description

Integrated solvent deasphalting and steam pyrolysis process for direct processing of crude oil{INTEGRATED SOLVENT DEASPHALTING AND STEAM PYROLYSIS PROCESS FOR DIRECT PROCESSING OF A CRUDE OIL}

This application claims the benefit of U.S. Provisional Application No. 61/591,783 filed January 27, 2012, the entire contents of which are incorporated herein by reference.

The present invention relates to an integrated solvent deasphalting and steam pyrolysis process for the direct processing of crude oil for the production of petrochemicals such as olefins and aromatics.

Lower olefins (ie ethylene, propylene, butylene and butadiene) and aromatics (ie benzene, toluene and xylene) are the basic intermediates widely used in the petrochemical and chemical industries. Thermal cracking or steam pyrolysis is the main type of process for forming this material, typically in the presence of steam and in the absence of oxygen. The feedstock for steam pyrolysis may include petroleum gas and distillate, such as naphtha, kerosene and gas oil. The availability of these feedstocks is usually limited and requires expensive energy-intensive process steps in crude oil refineries.

Studies were conducted using heavy hydrocarbons as feedstock for the steam pyrolysis reactor. The main disadvantage in the conventional heavy hydrocarbon pyrolysis operation was coke formation. For example, a steam cracking process for heavy liquid hydrocarbons is disclosed in US Pat. No. 4,217,204, in which mist of molten salt is introduced to the steam cracking reaction zone in an effort to minimize coke formation. In one example using Arabian light crude oil with a Conradson residual carbon content of 3.1% by weight, the cracking device can continue to run for 624 hours in the presence of molten salt. In the comparative example in which no molten salt was added, the steam cracking reactor is blocked and becomes inoperable after only 5 hours due to coke formation in the reactor.

In addition, the yield and distribution of olefins and aromatics using heavy hydrocarbons as feedstock for steam pyrolysis reactors is different from using light hydrocarbon feedstocks. Heavy hydrocarbons have a higher aromatic content than light hydrocarbons, as indicated by the higher Bureau of Mines Correlation Index (BMCI). BMCI is a measure of the aromaticity of the feedstock and is calculated as follows:

Where,

VAPB is the volume average boiling point of the Rankine temperature unit,

sp. gr. is the specific gravity of the feedstock.

As BMCI decreases, ethylene yield is expected to increase. Thus, high paraffin or low aromatic feeds are usually preferred for steam pyrolysis to obtain higher yields of the desired olefins and to avoid more undesirable product and coke formation in the reactor coil section.

The rate of absolute coke formation in a steam cracker is described by Kai et al. in "Coke Formation in Steam Crackers for Ethylene Production," Chem. Eng. & Proc. , vol. 41, (2002), 199-214. In general, the rate of absolute coke formation is in the order of increasing olefins>aromatics> paraffins, where olefins represent heavy olefins.

To respond to the growing demand for these petrochemicals, other types of supplies that may be available in bulk, such as crude oil, are attractive to manufacturers. The use of crude oil supplies minimizes or eliminates the potential for bottleneck refineries in the manufacture of this petrochemical product.

The steam pyrolysis process is specially developed and suitable for its intended purpose, but the speed of the feedstock is very limited.

The systems and processes herein provide a steam pyrolysis zone integrated with a solvent deasphalting zone that allows direct processing of crude oil feedstock to produce petrochemicals containing olefins and aromatics.

Integrated solvent deasphalting and steam pyrolysis processes for the direct processing of crude oil for the production of olefins and aromatic petrochemicals are used to produce deasphalted and demetallized oil streams and bottom asphalt phases. Filling the crude oil in a solvent deasphalting zone with an effective amount of solvent; Thermal cracking the deasphalted and demetallized oil stream in the presence of steam to produce a mixed product stream; Separating the mixed product stream; Recovering olefins and aromatics from the separated mixed product stream; And recovering pyrolysis fuel oil from the separated mixed product stream.

It should be understood that the term “crude oil” described herein includes whole crude oil from conventional sources that undergo some pretreatment. The term crude oil also includes water-oil separation; And/or gas-oil separation; And/or desalting; And/or stabilizing treatment.

Other aspects, embodiments and advantages of the process of the present invention are described in more detail below. Moreover, it is understood that both the above information and the following detailed description are merely illustrative examples of various aspects and embodiments, and are intended to provide an overview or basis for understanding the properties and characteristics of claimed features and embodiments. The accompanying drawings are illustrative and provided for further understanding of various aspects and embodiments of the process of the present invention.

The invention is described in more detail below with reference to the accompanying drawings:
1 is a process flow diagram of an embodiment of an integrated process described herein; And
2A-2C are schematic representations of perspective, top and side views of a vapor-liquid separation device used in certain embodiments of a steam pyrolysis unit in the integrated process described herein.

A flow diagram including an integrated solvent deasphalting and steam pyrolysis process and system is shown in FIG. 1. The integrated system includes a solvent deasphalting zone, a steam pyrolysis zone 30 and a product separation zone.

The solvent deasphalting zone generally includes a primary settling tank 14, a secondary settling tank 17, a deasphalting/demetallization oil (DA/DMO) separation zone 20 and a separator zone 23. do.

The primary settling tank 14 may be a feed stream 1 and a solvent (new solvent 29, recycle solvent 12, recycle solvent 24, or a combination comprising one or more of these solvent sources) It includes an inlet for receiving a combined stream 13 comprising a. The primary settling tank 14 also includes an outlet that discharges the primary DA/DMO phase 15 and several pipe outlets that discharge the primary asphalt phase 16. The secondary sedimentation tank 17 has two wooden distributors located at both ends of the primary DA/DMO phase 15, an outlet for discharging the secondary DA/DMO phase 19, and a secondary asphalt phase ( 18) Outlet to discharge. The DA/DMO separation zone 20 is a solvent-free DA for use as an inlet to receive the secondary DA/DMO phase 19, an outlet to discharge the solvent stream 12, and a steam pyrolysis zone feedstock. /DMO stream 21. The separator vessel 23 includes an inlet for receiving the primary asphalt phase 16, an outlet for discharging the solvent stream 24 and an outlet for discharging the lower asphalt phase 25.

The steam pyrolysis zone 30 is generally operated in a steam pyrolysis unit known in the art, ie, a convection section 32 and a pyrolysis section 32 which can be operated based on charging the thermal cracking feed into the convection section in the presence of steam. 34). In addition, in any particular embodiment described herein (indicated by the dotted line in FIG. 1 ), a vapor-liquid separation section 36 is included between section 32 and section 34. The vapor-liquid separation section 36 through which the heated steam cracking feed from the convection section 32 passes may be a separation device based on physical or mechanical separation of vapor and liquid.

In one embodiment, a vapor-liquid separation device is illustrated with reference to FIGS. 2A-2C. Similar arrangements of vapor-liquid separation devices are also described in US Patent Publication No. 2011/0247500, the entirety of which is incorporated herein by reference. In this device, vapor and liquid flow through the cyclone geometry, where the device isothermally operated at very low residence times. In general, the steam vortexes in a circular pattern, where heavier droplets and liquid are captured and channeled through the liquid outlet as a sulfur low-content fuel oil 38, e.g. added to a pyrolysis fuel oil blend, and the steam is pyrolysis section As a filling 37 for 34, it creates a force that is channeled through the vapor outlet. For example, in certain embodiments compatible with the residue fuel oil blend, the vaporization temperature and fluid velocity are varied to adjust the approximate temperature cutoff point, eg, about 540°C.

The quench zone 40 has an inlet in fluid communication with the outlet of the steam pyrolysis zone 30, an inlet for receiving the quench solution 42, an outlet for quenching the quenched mixed product stream 44, and a quench solution 46. It includes an outlet to discharge.

In general, the intermediate quenched mixed product stream 44 is converted to intermediate product stream 65 and hydrogen 62, which is purified in this process and recycled hydrogen stream 2 in the hydrogenation process reaction zone 4 ). The intermediate product stream 65 may be divided into one or multiple separation units, such as, for example, de-ethanizers, de-propanizers, and debutan absorbers (de) as is known to those skilled in the art. -butanizer) In the separating zone 70, which may be a plurality of fractionation towers comprising a column, it is generally fractionated with the final product and residue. For example, suitable devices are described in "Ethylene", Ullmann's Encyclopedia of Industrial Chemistry, Volume 12, pages 531-581, in particular FIGS. 24, 25 and 26, incorporated herein by reference in its entirety. It is done.

In general, the product separation zone 70 comprises an inlet in fluid communication with the product stream 65 and an outlet 78 for discharging methane, an outlet 77 for discharging ethylene, an outlet 76 for discharging propylene, buta It includes a plurality of product outlets 73-78 including an outlet 75 for discharging ene, an outlet 74 for discharging mixed butylene, and an outlet 73 for discharging pyrolysis gasoline. Additionally, an outlet is provided to drain the pyrolysis fuel oil 71. The lower asphalt phase 25 from the separator vessel 23 and optionally the rejected portion 38 from the vapor-liquid separation section 36 are combined with the pyrolysis fuel oil 71 and the mixed stream is a pyrolysis fuel oil blend ( 72), for example, can be discharged as a low sulfur fuel oil blend (processed further in an off-site refinery). Note that although six product outlets are shown, fewer or more outlets may be provided, for example depending on the placement and yield and distribution requirements of the separation unit used.

In an embodiment of the process using the arrangement shown in FIG. 1, crude oil feedstock 1 is mixed with solvents from one or more sources 29, 12 and 24. Then, the resulting mixture 13 is transferred to the primary settling tank 14. By mixing and sedimentation, two phases of the primary DA/DMO phase 15 and the primary asphalt phase 16 are formed in the primary sedimentation tank 14. The temperature of the primary settling tank 14 is low enough to recover all DA/DMO from the feedstock. For example, in the case of a system using n-butane, a suitable temperature range is about 60°C to 150°C, and a suitable pressure range is higher than the vapor pressure of n-butane at the operating temperature, for example, a solvent in a liquid phase. About 15 to 25 bar to maintain. For systems using n-pentane, a suitable temperature range is from about 60°C to about 180°C, and a suitable pressure range is also used to maintain the solvent at a pressure higher than the vapor pressure of n-pentane at the operating temperature, e.g., in the liquid phase. To about 10 to 25 bar. The temperature in the second settling tank is usually higher than the temperature in the first settling tank.

The primary DA/DMO phase 15 containing most of the solvent and the DA/DMO with a small amount of asphalt is discharged through the outlet and collector pipes (not shown) located above the primary sedimentation tank 14. The primary asphalt phase (16) containing 40-50% by volume of solvent is discharged through several pipe outlets located at the bottom of the primary settling tank (14).

The primary DA/DMO phase 15 enters two tree-like distributors at both ends of the secondary settling tank 17, which serves as the last step for extraction. The secondary asphalt phase 18 containing a small amount of solvent and DA/DMO is discharged from the secondary sedimentation tank 17 and recycled back to the primary sedimentation tank 14 to recover DA/DMO. A second DA/DMO phase 19 is obtained and passed through a DA/DMO separation zone 20 to obtain a solvent stream 12 and a solvent-free DA/DMO stream 21. More than 90% by weight of solvent charged to the sedimentation tank enters the DA/DMO separation zone 20, which is dimensioned to allow rapid and effective flash separation of the solvent from the DA/DMO. The primary asphalt phase 16 is sent to a separator vessel 23 for flash separation of the solvent stream 24 and the lower asphalt phase 25. The solvent streams 12 and 24 can be used as a solvent for the primary settling tank 14, minimizing the need for fresh solvent 29.

Solvents The solvents used in the deasphalting zone include pure liquid hydrocarbons such as propane, butane and pentane and mixtures thereof. The choice of solvent depends on the needs of the DAO and the quality and quantity of the final product. Operating conditions for the solvent deasphalting zone include temperatures below the critical point of the solvent; Solvent to oil ratios ranging from 2:1 to 50:1; And a range of pressures effective to keep the solvent/feed mixture in a liquid state in the sedimentation bath.

The substantially solvent-free DA/DMO stream 21 is optionally steam stripped (not shown) to remove any remaining solvent, and, for example, to the convection section 32 in the presence of an effective amount of steam allowed at the steam inlet (not shown). It is a pyrolysis feed stream that passes through. In the convection section 32, the mixture is heated to a predetermined temperature using, for example, one or more waste heat streams or other suitable heating arrangement. The heated mixture of light fractions and steam optionally passes into a vapor-liquid separation section 36 where portion 38 is rejected as a fuel oil component suitable for blending with pyrolysis fuel oil 71. The remaining hydrocarbon portion is transferred to a pyrolysis section 34 to produce a thermal cracked mixed product stream 39.

Steam pyrolysis zone 30 is run under parameters effective to crack DA/DMO stream 21 into the desired product including ethylene, propylene, butadiene, mixed butenes and pyrolysis gasoline. In certain embodiments, the temperature in the convection section and the pyrolysis section ranges from 400°C to 900°C; Steam to hydrocarbon ratios ranging from 0.3:1 to 2:1 in the convection section; And steam cracking is performed in the convection section and the pyrolysis section using conditions of residence time in the range of 0.05 seconds to 2 seconds.

In certain embodiments, vapor-liquid separation section 36 includes one or a plurality of vapor liquid separation devices 80 shown in FIGS. 2A-2C. The vapor liquid separation device 80 does not require power or chemical supply and is economical to operate and maintain. Generally, the device 80 includes three ports including an inlet port for receiving a vapor-liquid mixture, a vapor outlet port for discharging and collecting separated vapor and liquid, respectively, and a liquid outlet port. The device 80 converts the linear velocity of the incoming mixture by a full flow pre-rotational section to a reasonable rate, a control centrifugal effect to pre-separate the vapor from the liquid (residual oil) and separation of the vapor from the liquid (residual oil) It runs on the basis of a combination of phenomena that include the promoting cyclone effect. To achieve this effect, the device 80 includes a pre-rotation section 88, a controlled cyclone vertical section 90 and a liquid collector/sedimentation section 92.

2B, the pre-rotation section 88 is a controlled pre-rotating member between the cross-sectional area S1 and the cross-sectional area S2 and a controlled cyclone vertical section 90 located between the cross-sectional area S2 and the cross-sectional area S3. ). The vapor liquid mixture coming out of the inlet 82 having a diameter D1 enters the device tangentially in the cross-sectional area S1. The area of the entry section S1 for the incoming flow is at least 10% of the area of the inlet 82 according to the following equation:

The preliminary rotating member 88 defines a curved flow path and is characterized in that the cross-sectional area is constant, reduced, or increased from the inlet cross-sectional area S1 to the exit cross-sectional area S2. The ratio between the outlet cross-sectional area and the inlet cross-sectional area S1 from the controlled preliminary rotating member S2 ranges from 0.7≤S2/S1≤1.4 in certain embodiments.

The rotational speed of the mixture depends on the radius of the curvature R1 of the center line of the preliminary rotating member 38, and the center line is a curved line that touches all the central points of the continuous cross-sectional surface of the preliminary rotating member 88. Is defined. In certain embodiments, the radius of curvature R1 is in the range 2≦R1/D1≦6, and the opening angle is in the range 150°≦αR1≦250°.

The cross-sectional shape in the inlet section S1 is generally shown as a square, but may be rectangular, rounded rectangular, circular, elliptical or other straight, curved or a combination of the above-mentioned shapes. In a particular embodiment, the shape of the cross-sectional area along the curved path of the pre-rotational member 38 through which the fluid passes continues to change, for example from a generally rectangular shape to a rectangular shape. The continuously varying cross-sectional area of the member 88 in a rectangular shape advantageously maximizes the open area so that the gas is separated from the liquid mixture in the initial stage and a uniform velocity profile is obtained, and shear stress in the fluid flow is minimized.

The fluid flow from the preliminary rotating member 88 controlled from the cross-sectional area S2 passes through the section S3 to the cyclone vertical section 40 controlled through the connecting member. The connecting member comprises an open area open to and connected to the inlet in the controlled cyclone vertical section 90. The fluid flow enters the cyclone vertical section 90 controlled at a high rotational speed, creating a cyclone effect. The ratio between the connecting member outlet cross-sectional area S3 and the inlet cross-sectional area S2 ranges from 2≤S3/S1≤5 in certain embodiments.

The mixture at high rotational speed enters the cyclone vertical section 90. The kinetic energy decreases, and the vapor separates from the liquid under the cyclone effect. Cyclone is formed at the upper water level 90a and the lower water level 90b of the cyclone vertical section 90. At the upper water level 90a, the mixture is characterized by a high concentration of vapor, and at the lower water level 90b, the mixture is characterized by a high concentration of liquid.

In a particular embodiment, the inner diameter D2 of the cyclone vertical section 90 ranges from 2≤D2/D1≤5, can be constant along its height, and the length LU of the upper portion 90a is 1.2≤LU /D2≤3 range, and the length LL of the lower portion 90b is 2≤LL/D2≤5 range.

The end of the cyclone vertical section 90 adjacent to the steam outlet 34 is connected to a partially open release vertical tube and to the pyrolysis section of the steam pyrolysis unit. The diameter (DV) of the partially open release ranges from 0.05≤DV/D2≤0.4 in certain embodiments.

Thus, in certain embodiments, depending on the nature of the incoming mixture, a large volume fraction of vapor in this mixture leaves the device 80 from the outlet 84 through a partially open release pipe having a diameter (DV). Liquids with low or no vapor concentration (e.g., resid) leave through the bottom portion of the cyclone vertical section 90 having a cross-sectional area S4 and are collected in the liquid collector and settling pipe 92.

The connecting portion between the cyclone vertical section 90 and the liquid collector and sedimentation pipe 92 is 90° in a particular embodiment. In certain embodiments, the inner diameter of the liquid collector and sedimentation pipe 92 ranges from 2≤D3/D1≤4, is constant over the pipe length, and the length (LH) of the liquid collector and sedimentation pipe 92 is 1.2≤LH /D3≤5 range. The liquid with low vapor volume fraction is removed from the device through a pipe 86 having a diameter of DL, located adjacent to or at the bottom of the settling pipe, and in certain embodiments this diameter ranges from 0.05≤DL/D3≤0.4 to be.

Although various members have been described separately and in separate parts, the device 80 can be formed as a monolithic structure, for example cast or molded, or it can be, for example, a member described herein And those skilled in the art will understand that it is possible to assemble from separate parts by welding or otherwise attaching separate parts that do or do not exactly correspond to the parts.

Although various dimensions are described as diameter, it is understood that this value may also be the same effective diameter in embodiments where the part part is not cylindrical.

The mixed product stream 39 is passed through a separate inlet to the inlet of the quench zone 40 with quench solution 42 (eg, water and/or pyrolysis fuel oil), for example about 300 A quenched mixed product stream 44 with reduced temperature, such as °C, is prepared, and spent quench solution 46 is drained.

The gas mixture effluent 39 from the cracker is typically a mixture of hydrogen, methane, hydrocarbons, carbon dioxide and hydrogen sulfide. After cooling with water or oil quenching, the mixture 44 is typically condensed in a multistage condenser zone 51 in steps 4-6 to produce a condensed gas mixture 52. The condensed gas mixture 52 is treated with a caustic treatment unit 53 to produce a gas mixture 54 lacking hydrogen sulfide and carbon dioxide. The gas mixture 54 is further condensed in the condenser zone 55, and the resulting cracked gas 56 is cryogenically treated in a typically dehydrated unit 57 and further dried using molecular sieves.

The cold cracked gas stream 58 from unit 57 is passed through a demethane absorber tower 59 from which an overhead stream 60 comprising hydrogen and methane is produced from the cracked gas stream. Thereafter, the bottoms stream 65 from the demethane absorber tower 59 is subjected to further processing in a product separation zone 70 comprising a fractionation column comprising a deethanizer, a depropane absorber and a debutan absorber tower. To transport. Process batches with different orders of demethane absorber, deethan absorber, depropane absorber and debutan absorber can also be used.

Following the process herein, after separation from methane in the demethane absorber tower 59 and hydrogen recovery in the unit 61, hydrogen 62 having a purity of typically 80-95% by volume is obtained, which It can be further refined as needed or combined with other exhaust gases at the refinery. In addition, a portion of the hydrogen from stream 62 can be used for the hydrogenation reaction of acetylene, methylacetylene and propadiene (not shown). Further, according to the process herein, the methane stream 63 may optionally be recycled to the steam cracker and used as fuel for the burner and/or heater.

The bottoms stream 65 from the demethane absorber tower 59 is transported to the inlet of the product separation zone 70 and the product stream methane, ethylene discharged through the outlets 78, 77, 76, 75, 74 and 73, respectively. , Propylene, butadiene, mixed butylene and pyrolysis gasoline. Pyrolysis gasoline generally contains C5-C9 hydrocarbons, and benzene, toluene and xylene can be extracted from this fraction. Optionally, one or both of the lower asphalt phase 25 from the vapor-liquid separation section 36 and the non-vaporized heavy liquid fraction 38 are also used as a pyrolysis fuel oil 71 (e.g., a "C10+" stream). Known, materials boiling at a temperature higher than the boiling point of the lowest boiling point C10 compound), and the mixed stream can be discharged as a pyrolysis fuel oil blend 16 (processed further in an off-site refinery (not shown)). In certain embodiments, the lower asphalt phase 25 may be transported to an asphalt striper (not shown), where any remaining solvent is stripped, for example, by steam.

Solvent deasphalting is a unique separation process in which residual oil is separated by molecular weight (density) instead of boiling point, as in a vacuum distillation process. Thus, the solvent deasphalting process produces deasphalted oils (DAOs) with low contaminants rich in paraffin-type molecules, resulting in a reduction in BMCI compared to initial feedstocks or hydrogenated process feedstocks.

Solvent deasphalting is usually carried out under critical conditions of the solvent with a paraffin stream in the range of 3 to 7 carbon atoms, in a particular embodiment 4 to 5 carbon atoms. Table 1 describes the properties of the solvents commonly used in solvent deasphalting.

The feed is mixed with a light paraffin solvent having a carbon number in the range of 3 to 7, and the deasphalted oil is solubilized in the solvent. Insoluble pitch precipitates from the mixed solution and separates from the DAO phase (solvent-DAO mixture) in the extractor.

Solvent deasphalting is performed in the liquid phase, so the temperature and pressure are thus set. There are two steps for phase separation in solvent deasphalting. In the first separation step, the temperature is kept lower than in the second step to separate the bulk of asphaltenes. The second stage temperature is maintained to control the deasphalted/demetallized oil (DA/DMO) quality and quantity. Temperature greatly influences the quality and quantity of DA/DMO. Increasing extraction temperature reduces deasphalted/demetallized oil yield, which means DA/DMO is lighter, less viscous, and contains less metal, asphaltenes, sulfur and nitrogen. Temperature reduction has the opposite effect. Generally, the DA/DMO yield decreases as the quality increases by raising the extraction system temperature, and increases as the quality decreases by lowering the extraction system temperature.

The composition of the solvent is an important process variable. In general, the solubility of the solvent increases as the critical temperature increases with C3<iC4<nC4<iC5. Increasing the critical temperature of the solvent increases the DA/DMO yield. However, note that solvents with lower critical temperatures have lower selectivity, resulting in lower quality DA/DMO.

The volume ratio of solvent-to-solvent deasphalting unit charge affects selectivity and, to a lesser extent, DA/DMO yield. Higher solvent to oil ratio produces higher quality DA/DMO for fixed DA/DMO yield. Higher solvent-to-oil ratios are desirable due to better selectivity, but can increase operating costs, so the solvent-to-oil ratio is usually limited to a narrow range. The composition of the solvent will also help establish the required solvent to oil ratio. The required solvent to oil ratio decreases as the critical solvent temperature increases. Thus, the solvent to oil ratio is a function of desired selectivity, operating cost and solvent composition.

The methods and systems herein provide improvements over known steam pyrolysis cracking processes:

The use of crude oil as a feedstock for the production of petrochemicals such as olefins and aromatics;

The hydrogen content of the feed to the steam pyrolysis zone is enriched for high yields of olefins;

In certain embodiments, the coke precursor is significantly removed from the initial total crude oil to reduce coke formation in the radial coil; And

In certain embodiments, additional impurities such as metal, sulfur and nitrogen compounds are also significantly removed from the starting feed, avoiding post-treatment of the final product.

The methods and systems of the present invention are described above and in the accompanying drawings; Modifications are obvious to those skilled in the art, and the protection scope of the present invention should be defined by the following claims.

Claims (21)

An integrated solvent deasphalting and steam pyrolysis method for directly processing crude oil to produce olefins and aromatic petrochemicals,
a. Mixing the crude oil feedstock with a makeup solvent and optionally a fresh solvent;
b. Transferring the mixture to a primary sedimentation tank in which primary deasphalted and demetallized oil phases and primary asphalt phases are formed;
c. Transferring the primary deasphalted and demetallized oil phases to a secondary sedimentation tank in which secondary deasphalted and demetallized oil phases and secondary asphalt phases are formed;
d. Recirculating the secondary asphalt phase to the primary sedimentation tank to recover additional deasphalted and demetallized oils;
e. Transporting the secondary deasphalted and demetallized oil phases to a deasphalted and demetallized oil separation zone to obtain a recycle solvent stream and a substantially solvent-free deasphalted and demetallized oil stream. step;
f. Transporting the primary asphalt phase to a separator vessel for further recycle solvent stream and flash separation on the lower asphalt;
g. Heat cracking the substantially solvent-free deasphalted and demetallized oil stream in the presence of steam to produce a mixed product stream;
h. Separating the heat cracked mixed product stream;
i. Recovering olefins and aromatics from the separated mixed product stream; And
j. A method of integrated solvent deasphalting and steam pyrolysis comprising recovering pyrolysis fuel oil from the separated mixed product stream. The method of claim 1, step (h),
Condensing the heat cracked mixed product stream into a plurality of condensation steps;
Caustic treatment of the condensed heat cracked mixed product stream to produce a heat cracked mixed product stream with reduced hydrogen sulfide and carbon dioxide content;
Condensing the heat cracked mixed product stream with reduced hydrogen sulfide and carbon dioxide content;
Dehydrating the condensed heat cracked mixed product stream with reduced hydrogen sulfide and carbon dioxide content;
Recovering hydrogen from the dehydrated condensed heat cracked mixed product stream with reduced hydrogen sulfide and carbon dioxide content; And
Comprising obtaining olefins and aromatics as in step (i) and pyrolysis fuel oil as in step (j) from the rest of the dehydrated condensed heat cracked mixed product stream with reduced hydrogen sulfide and carbon dioxide content, Integrated solvent deasphalting and steam pyrolysis methods. 3. The method of claim 2, wherein methane is separated and recovered from the dehydrated condensed heat cracked mixed product stream with reduced hydrogen sulfide and carbon dioxide content for use as a fuel for a burner and/or heater in the heat cracking step. Integrated solvent deasphalting and steam pyrolysis method further comprising a. The method of claim 1, wherein the thermal cracking step comprises heating the deasphalted and demetallized oil stream in a convection section of a steam pyrolysis zone, vapor fraction and liquid of the heated deasphalted and demetallized oil stream. A method of integrated solvent deasphalting and steam pyrolysis comprising separating into fractions, passing the vapor fraction through a pyrolysis section of a steam pyrolysis zone and evacuating the liquid fraction. 5. The method of integrated solvent deasphalting and steam pyrolysis according to claim 4, wherein the discharged liquid fraction is blended with the pyrolysis fuel oil recovered in step (j). The integrated solvent deasphalting according to claim 4, wherein the step of separating the heated deasphalted and demetallized oil streams into a vapor fraction and a liquid fraction is by a vapor-liquid separation device based on physical and mechanical separation. Pyrolysis and steam pyrolysis methods. The method of claim 6, wherein the vapor-liquid separation device,
A pre-rotation section having an inlet for receiving a flowing fluid mixture, a connecting member, and a curved conduit from the inlet to an outlet contacting the connecting member,
Controlled cyclone vertical section; And
A liquid collector/sedimentation section through which the liquid passes,
The controlled cyclone vertical section,
An entrance contacting the preliminary rotating section through the connecting member, and
A method of integrated solvent deasphalting and steam pyrolysis, having an open release riser at the upper end of the cyclone vertical section through which steam passes. The method of claim 1, wherein the lower asphalt phase is blended with the pyrolysis fuel oil recovered in step (j). An integrated solvent deasphalting and steam pyrolysis system for directly processing crude oil to produce olefins and aromatic petrochemicals,
A solvent deasphalting mixing zone comprising an inlet to the crude oil feedstock, an inlet to a fresh solvent, an inlet to a makeup solvent, and an outlet;
A primary sedimentation tank in fluid communication with the solvent deasphalting mixing zone outlet, the primary sedimentation tank comprising an inlet for receiving a mixture and secondary asphalt phase from the solvent deasphalting mixing zone, primary deasphalting and Has an outlet for draining the demetallized oil phase, and an outlet for the primary asphalt phase;
The primary sedimentation tank is a secondary sedimentation tank in fluid communication with the primary deasphalted and demetallized oil phase outlet, the secondary sedimentation tank is an inlet for receiving the primary deasphalted and demetallized oil phase, Has an outlet for discharging the secondary deasphalted and demetallized oil phase, and an outlet for the secondary asphalt phase;
Having an outlet for a recycle solvent stream, and an outlet for a substantially solvent-free deasphalted and demetallized oil stream, and for receiving the secondary deasphalted and demetallized oil phases, the secondary deasphalted and Deasphalting and demetallization separation zones in fluid communication with the demetallized oil phase outlet,
Wherein the outlet for a substantially solvent-free deasphalted and demetallized oil stream is in fluid communication with the inlet of the thermal cracking zone; And
A solvent deasphalting zone comprising a separator vessel in fluid communication with the outlet of the primary asphalt phase to receive the primary asphalt phase, an outlet for the recycle solvent and an outlet for the lower asphalt phase,
A thermal cracking zone comprising a thermal cracking convection section and a thermal cracking pyrolysis section, wherein the thermal cracking convection section is inlet in fluid communication with a substantially solvent-free deasphalting and demetallization oil stream outlet of the solvent deasphalting zone, And an outlet, wherein the thermal cracking pyrolysis section has an inlet in fluid communication with an outlet of the convection section, and a pyrolysis section outlet;
A quench zone having an outlet for discharging the intermediate quenched mixed product stream and an outlet for discharging the quench solution, in fluid communication with the pyrolysis section outlet; And
An integrated solvent deasphalting and steam pyrolysis system comprising a product separation zone in fluid communication with the intermediate quenched mixed product stream outlet, having a hydrogen outlet, one or more olefin product outlets and one or more pyrolysis fuel oil outlets. The method of claim 9,
A first condenser zone having an inlet in fluid communication with the quench zone outlet for discharging the intermediate quenched mixed product stream, and an outlet for discharging the condensed gas mixture;
A caustic treatment unit having an inlet in fluid communication with the outlet of the first condenser zone for discharging a condensed gas mixture, and an outlet for discharging a gas mixture depleted of hydrogen sulfide and carbon dioxide;
A second condenser zone having an inlet in fluid communication with the caustic treatment unit outlet, and an outlet for discharging condensed cracked gas;
A dewatering zone having an inlet in fluid communication with the outlet of the second condenser zone, and an outlet for discharging the cold cracked gas stream; And
Further comprising a demethane absorber unit having an inlet in fluid communication with the outlet of the dewatering zone, an outlet for discharging an overhead stream comprising hydrogen and methane, and an outlet for discharging the bottoms stream, and
The product separation zone comprises a deethanizer absorber tower, a depropane absorber tower and a debutan absorber tower, wherein the deethanizer absorber tower is an integrated solvent deasphalting and steam pyrolysis system in fluid communication with the bottoms stream of the demethane absorber unit. . The method of claim 10,
An integrated solvent deasphalting and steam pyrolysis system further comprising a burner and/or heater associated with a thermal cracking zone in fluid communication with the demethane absorber unit. The method according to any one of claims 9 to 11,
Further comprising a vapor-liquid separator having an inlet, a vapor fraction outlet, and a liquid fraction outlet in fluid communication with the thermal cracking convection section outlet, the vapor fraction outlet being in integrated solvent deasphalting and in fluid communication with the pyrolysis section. Steam pyrolysis system. The method of claim 12,
The vapor-liquid separator is an integrated solvent deasphalting and steam pyrolysis system that is a physical or mechanical device for the separation of vapors and liquids. The method of claim 12,
The vapor-liquid separator is:
A pre-rotation section having an inlet for receiving a flowing fluid mixture, a connecting member, and a curved conduit from the inlet to an outlet contacting the connecting member;
Controlled cyclone vertical section, wherein the controlled cyclone vertical section,
An entrance contacting the preliminary rotating section through the connecting member, and
Has an open release vertical tube at the upper end of the controlled cyclone vertical section through which steam passes; And
An integrated solvent deasphalting and steam pyrolysis system comprising a liquid collector/sedimentation section through which liquid passes as the discharged liquid fraction. The method according to any one of claims 9 to 11,
Further comprising a deasphalted and demetallized oil separator having an inlet, a light fractional outlet, and a heavy fractional outlet in fluid communication with a deasphalted and demetallized oil stream outlet of the solvent deasphalted zone, wherein the light The fractional outlet is an integrated solvent deasphalting and steam pyrolysis system in fluid communication with the pyrolysis section. The method of claim 15,
The deasphalted and demetallized oil separator is a flash separator, an integrated solvent deasphalting and steam pyrolysis system. The method of claim 15,
The deasphalted and demetallized oil separator is an integrated solvent deasphalting and steam pyrolysis system that is a physical or mechanical device for the separation of vapors and liquids. The method of claim 15,
The deasphalted and demetallized oil separator,
A pre-rotation section having an inlet for receiving a flowing fluid mixture, a connecting member, and a curved conduit from the inlet to an outlet contacting the connecting member;
Controlled cyclone vertical section, wherein the controlled cyclone vertical section,
An entrance contacting the preliminary rotating section through the connecting member, and
Has an open release vertical tube at the upper end of the controlled cyclone vertical section through which steam passes; And
An integrated solvent deasphalting and steam pyrolysis system comprising a liquid collector/sedimentation section through which liquid passes as the discharged liquid fraction. The method of claim 7,
The pre-rotational section inlet has a cross-sectional area S1, and the pre-rotational section exit has a cross-sectional area S2, where the ratio between S2 and S1 is 0.7 ≤ S2/S1 ≤ 1.4,
Wherein the vapor-liquid separation device comprises a conduit flowing to the inlet of the vapor-liquid separation device having a diameter D1, and
Wherein the curved conduit has an integrated angle of solvent deasphalting and steam characterized by having a radius of curvature R1 in the range of 2 ≤ R1/D1 ≤ 6 and an open angle αR1 between S1 and S2 in the range of 150°≤ αR1 ≤250°. Pyrolysis method. The method of claim 14,
The pre-rotational section inlet has a cross-sectional area S1, and the pre-rotational section exit has a cross-sectional area S2, where the ratio between S2 and S1 is 0.7 ≤ S2/S1 ≤ 1.4,
Wherein the vapor-liquid separator comprises a conduit flowing to the inlet of the vapor-liquid separator having a diameter D1, and
Wherein the curved conduit has an integrated angle of solvent deasphalting and steam characterized by having a radius of curvature R1 in the range of 2 ≤ R1/D1 ≤ 6 and an open angle αR1 between S1 and S2 in the range of 150°≤ αR1 ≤250°. Pyrolysis system. The method of claim 18,
The pre-rotational section inlet has a cross-sectional area S1, and the pre-rotational section exit has a cross-sectional area S2, where the ratio between S2 and S1 is 0.7 ≤ S2/S1 ≤ 1.4,
Wherein the vapor-liquid separator comprises a conduit flowing to the inlet of the vapor-liquid separator having a diameter D1, and
Wherein the curved conduit has an integrated angle of solvent deasphalting and steam characterized by having a radius of curvature R1 in the range of 2 ≤ R1/D1 ≤ 6 and an open angle αR1 between S1 and S2 in the range of 150°≤ αR1 ≤250°. Pyrolysis system.

Images