Distillate two-phase hydrogenation reactor and hydrogenation method

Abstract

A hydrogenation method and distillate two-phase hydrogenation reactor in which the size of an upper space of the reactor is greater than that of a lower catalyst bed part. The reactor comprises 2 to 4 catalyst beds. An inner component for gas replenishment and for stripping a liquid-phase stream containing impurities is arranged between at least one adjacent catalyst bed and comprises a separator plate and exhaust pipes. The separator plate is provided with multiple downcomer through holes. The separator plate is connected with a plurality of exhaust pipes. The exhaust pipes are vertically arranged above the separator plate. The top parts of the exhaust pipes are in contact with the lower part of the upper catalyst bed.

Claims

1. A distillate two-phase hydrogenation reactor, wherein the size of an upper space of the reactor is greater than that of a lower catalyst bed part, and wherein the reactor comprises at least 2 catalyst beds.

2. The distillate two-phase hydrogenation reactor according to claim 1, wherein the reactor comprises 2 to 4 catalyst beds.

3. The distillate two-phase hydrogenation reactor according to claim 1, wherein an inner component for gas replenishment and for stripping a liquid-phase stream containing impurities is arranged between at least one adjacent catalyst bed.

4. The distillate two-phase hydrogenation reactor according to claim 3, wherein the inner component comprises a gas-liquid contact component and a stripping component.

5. The distillate two-phase hydrogenation reactor according to claim 4, wherein the gas-liquid contact component and the stripping component are arranged together.

6. The distillate two-phase hydrogenation reactor according to claim 3, wherein the inner component comprises a separator plate and exhaust pipes.

7. The distillate two-phase hydrogenation reactor according to claim 6, wherein the separator plate is provided with multiple downcomer through holes.

8. The distillate two-phase hydrogenation reactor according to claim 6, wherein the separator plate is connected with the exhaust pipes.

9. The distillate two-phase hydrogenation reactor according to claim 6, wherein the exhaust pipes are vertically arranged above the separator plate.

10. The distillate two-phase hydrogenation reactor according to claim 6, wherein the top parts of the exhaust pipes are in contact with the lower part of the upper catalyst bed.

11. A liquid-phase hydrogenation method for removing impurities from a hydrocarbon raw material, characterized in using the reactor according to claim 1.

12. The liquid-phase hydrogenation method according to claim 11, comprising: circulating a portion of a hydrogenated liquid-phase product, and mixing it with fresh raw material into a liquid-phase material, forming, after dissolving hydrogen, a saturated liquid-phase stream, which is introduced into the reactor from the upper part, carrying out a hydrogenation reaction on a hydrogenation catalyst bed at the upper part of the reactor, passing an effluent after the reaction through the internal component to be mixed with hydrogen gas, to supplement the amount of hydrogen gas dissolved in the liquid-phase material, introducing the liquid-phase material supplemented with dissolved hydrogen into the next hydrogenation catalyst bed, introducing gas-phase hydrogen into the catalyst bed through the exhaust pipes of the stripping component, and forming a gas-liquid countercurrent on the catalyst bed, so that the concentration of hydrogen gas on the catalyst bed is increased, wherein the hydrogen gas strips hydrogen sulfide and ammonia impurities produced in the reaction.

13. The liquid-phase hydrogenation method according to claim 12, wherein the volume ratio of the circulated liquid-phase product to the fresh raw material is 0.1:1 to 10:1.

14. The liquid-phase hydrogenation method according to claim 12, wherein the amount of hydrogen gas supplemented among the catalyst beds is 0.5:1 to 10:1 in terms of hydrogen-oil volume ratio.

15. The liquid-phase hydrogenation method according to claim 12, wherein the reaction temperature at which the liquid-phase material is passed through the catalyst bed is 130 to 450 C.

16. The liquid-phase hydrogenation method according to claim 12, wherein the reaction pressure at which the liquid-phase material is passed through the catalyst bed is 1 to 20 MPa.

17. The liquid-phase hydrogenation method according to claim 12, wherein and the liquid hourly space velocity (LHSV) at which the liquid-phase material is passed through the catalyst bed is 0.5 to 15 h.sup.1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of the distillate two-phase hydrogenation reactor of the present invention.

(2) FIG. 2 is a schematic diagram of the internal component of the distillate two-phase hydrogenation reactor of the present invention.

(3) FIG. 3 is a top view of the internal component of the distillate two-phase hydrogenation reactor of the present invention.

(4) In the drawing: 1reactor inlet, 2hydrogen gas inlet, 3first catalyst bed, 4second catalyst bed, 5gas-liquid contact and stripping component, 6exhaust pipe, 7downcomer through hole, 8exhaust system of the reactor, 9reactor outlet.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(5) The structure of the reactor and the operation method of the hydrogenation process of the present invention will be further explained below by referring to the drawings.

(6) As shown in FIG. 1 and FIG. 2, a specific structure of the reactor of the present invention includes a reactor inlet 1, a hydrogen gas inlet 2, and a reactor outlet 9, wherein the size of the upper space of the reactor is slightly greater than that of the lower catalyst bed part, and two catalyst beds (a first catalyst bed 3 and a second catalyst bed 4) are used. An inner component for gas replenishment and for stripping a liquid-phase stream containing impurities is arranged between the two catalyst beds. The inner component comprises a separator plate 5 and exhaust pipes 6. The separator plate is provided with downcomer through holes 7. The separator plate 5 is connected with exhaust pipes 6. The exhaust pipes 6 are arranged above the separator plate 5. The top parts of the exhaust pipes 6 are in contact with the lower part of the upper catalyst bed.

(7) A portion of a hydrogenated liquid-phase product is circulated, and mixed with fresh raw material into a liquid-phase material, after dissolving hydrogen, a saturated liquid-phase stream is formed, which is introduced into the reactor from the upper part, a hydrogenation reaction is carried out on the first hydrogenation catalyst bed, an effluent after the reaction passes through the internal component to be mixed with hydrogen gas, to supplement the amount of hydrogen gas dissolved in the liquid-phase material, the liquid-phase material supplemented with dissolved hydrogen is introduced into the second hydrogenation catalyst bed; the gas-phase hydrogen is introduced into the first catalyst bed through the exhaust pipes of the stripping component, a gas-liquid countercurrent is formed on the catalyst bed, meanwhile the hydrogen gas strips the hydrogen sulfide and ammonia impurities produced in the reaction. The reaction effluent from the second catalyst bed is discharged from the reactor, and then a portion thereof is circulated and another portion thereof is introduced into the product tank.

(8) The present invention will be further explained by the following examples.

(9) The catalyst used in the experiment is an industrially used hydrogenation and hydrocracking catalyst, including PHF-101 diesel hydrodesulfurization catalyst, PHT-01 heavy oil hydrogenation pretreatment catalyst, PHC-03 hydrocracking catalyst, which are developed and produced by Research Institute of Petroleum Processing of Petrochina. The physical and chemical property indexes thereof are shown in Table 1.

Example 1

(10) The mixed diesel oil was sufficiently mixed with hydrogen gas for dissolving hydrogen, and then introduced into the hydrogenation reactor under the reaction conditions of the hydrogen partial pressure at 6.0 MPa, the reaction temperature at 311 C., and the amount of hydrogen gas supplemented among the catalyst beds being 1:1 in terms of hydrogen-oil volume ratio. A portion of the liquid-phase product passed through the circulation pump as the circulated oil, and was mixed with fresh raw material for dissolving hydrogen, and then introduced into the reactor, and another portion of the liquid-phase product was introduced into the product tank in the form of product. The properties of the feedstock oil and the properties of the products are listed in Table 2.

(11) As seen from Table 2, the sulfur and nitrogen content in the diesel oil can be reduced remarkably by the use of this technology.

Example 2

(12) The heavy gatch feedstock was sufficiently mixed with hydrogen gas for dissolving hydrogen, and then introduced into the hydrogenation reactor under the reaction conditions of the hydrogen partial pressure at 12.0 MPa, the reaction temperature at 370 C., and the amount of hydrogen gas supplemented among the catalyst beds being 3:1 in terms of hydrogen-oil volume ratio. A portion of the liquid-phase product passed through the circulation pump as the circulated oil, and was mixed with fresh raw material for dissolving hydrogen, and then introduced into the reactor, and another portion of the liquid-phase product was introduced into the product tank in the form of product. The properties of the feedstock oil and the properties of the products are listed in Table 3.

(13) As seen from Table 3, when the mixed gatch containing 10 wt % coker gatch is used as the raw material, the content of sulfur and nitrogen impurities in the heavy gatch can be reduced remarkably by the use of this technology.

Example 3

(14) The gatch feedstock processed by Example 2 was sufficiently mixed with hydrogen gas for dissolving hydrogen, and then introduced into the hydrogenation reactor under the reaction conditions of the hydrogen partial pressure at 12.0 MPa, the reaction temperature at 385 C., and the amount of hydrogen gas supplemented among the catalyst beds being 7:1 in terms of hydrogen-oil volume ratio. A portion of the liquid-phase product passed through the circulation pump as the circulated oil, and was mixed with fresh raw material for dissolving hydrogen, and then introduced into the reactor, and another portion of the liquid-phase product was introduced into the product tank in the form of product, and then cut according to the true boiling point. The properties of the feedstock oil are listed in Table 4, and the product distribution and properties are listed in Table 5.

(15) As seen from Table 5, when the mixed gatch containing 10 wt % coker gatch is used as the raw material, under the process conditions of controlling the tail oil yield (>370 C.) at about 20 wt %, high-quality jet fuel and clean diesel oil can be produced by the use of this technology.

Comparative Example 1

(16) As compared with Example 1, the mixed diesel oil having the same properties was processed, but there is no internal component between the two catalyst beds in the reactor, and all of the hydrogen gas were introduced into the reactor from the reactor inlet. Other process conditions are the same as those in Example 1, and the properties of the refined diesel oil are shown in Table 6. It can be seen from Table 6 that the reaction temperature in the reactor of the present invention is 15 C. lower than that of the conventional reactor, but the product properties are better.

(17) TABLE-US-00001 TABLE 1 Physical and chemical property indexes of catalysts Catalyst No. PHF-101 PHT-01 PHC-03 Metal composition WO.sub.3 25.1 25.1 MoO.sub.3 20 to 30 NiO 3.2 3 to 10 5.3 Pore volume, 0.37 0.33 0.35 mL/g Specific surface 150 160 190 area, m2/g Shape trefoil trefoil cylindrical

(18) TABLE-US-00002 TABLE 2 Properties of the feedstock oil and the experimental result of Example 1 Mixed diesel Generated oil by Generated oil Mixed Mixed diesel oil oil refining by refining Item diesel oil (160 to 230 C.) (>230 C.) (160 to 230 C.) (>230 C.) Density (20 C.), g/cm.sup.3 0.8350 0.8110 0.8731 0.8122 0.8614 Sulphur content, g/g 1020.0 541.8 1602.1 2.3 7.9 Nitrogen content, g/g 881.8 267.7 1330.6 8.9 9.8

(19) TABLE-US-00003 TABLE 3 Properties of the feedstock oil and the experimental result of Example 2 Item Heavy gatch Generated oil Density (20 C.), g/cm3 0.8559 0.8502 Sulphur content, g/g 780.0 8.1 Nitrogen content, g/g 697.0 5.2

(20) TABLE-US-00004 TABLE 4 Properties of the feedstock oil of Example 3 Items Analytical result Density (20 C.), g/cm3 0.8559 Boiling range, C. IBP/10% 249/333 30%/50% 376/405 70%/90% 438/478 95%/EBP 492/519 Sulphur content, g/g 780.0 Nitrogen content, g/g 697.0 BMCI value 22.2

(21) TABLE-US-00005 TABLE 5 Experiment result of Example 3 Product distribution Item and properties C.sub.5.sup.+ liquid yield, wt. % 98.5 Product yield and quality 65 to 165 C. heavy naphtha yield, wt. % 15.69 Sulphur content, g/g <0.5 Nitrogen content, g/g <0.5 165 to 260 C. jet fuel yield, wt. % 23.83 Freezing point, C. 51 Smoke point, C. 30 260 to 370 C. diesel oil yield, wt. % 35.42 Cetane index 83.2 Condensation point, C. 2 165 to 370 C. diesel oild yield, wt. % 59.25 >370 C. tail oil yield, wt. % 19.80 BMCI value 7.6

(22) TABLE-US-00006 TABLE 6 Properties of the feedstock oil and the experimental result of Comparative Example 1 Comparative Item Example 1 Example 1 Reaction temperature, C. 326 311 Hydrogen partial pressure, MPa 6.0 6.0 Generated oil of the reactor Generated oil of without internal the reactor of the Mixed Mixed diesel oil component present invention Properties of oil product diesel oil (>230 C.) (>230 C.) (>230 C.) Density, (20 C.), g/cm3 0.8350 0.8731 0.8501 0.8614 Sulphur content, g/g 1020.0 1602.1 40.0 7.9 Nitrogen content, g/g 881.8 1330.6 48.0 9.8

INDUSTRIAL APPLICABILITY

(23) In the hydrogenation method with product circulation according to the present invention, two or more reactors may be used in series (the effluent from one reactor is introduced into the next reactor) or in parallel (the material is introduced into different reactors, respectively) as needed.

(24) In the above-mentioned liquid-phase hydrogenation method, it is possible to use a suitable hydrogenation catalyst such as hydrorefining catalyst, hydro-upgrading catalyst, hydrogenation catalyst, hydrocracking catalyst according to the requirement of the reaction, to achieve different hydrogenation purposes. Various catalysts may be selected from commercial catalysts, or be prepared according to the prior art.

(25) By the use of the abovementioned reactor, the liquid-phase hydrogenation method of the present invention can effectively replenish hydrogen gas in a liquid-phase raw material, form a gas-liquid countercurrent on the catalyst beds, increase the concentration of hydrogen gas, remove hydrogen sulfide and ammonia produced by the reaction, reduce inhibitory effects of H.sub.2S and NH.sub.3 on a subsequent hydrogenation reaction, enhance hydrogenation efficiency, and improve raw material applicability. The method does not need circulating hydrogen or circulating hydrogen compressor, which can reduce the equipment investment and the operation cost.

(26) The present invention is mainly used for the deep desulfurization, denitrification and dearomatization of inferior diesel oil components, the production of clean diesel oil, and the hydrorefining of naphtha, jet fuel, lubricating oil, paraffin and the like to produce high-quality oil products, and the process of manufacturing high-quality clean jet fuel and diesel oil by means of mild hydrocracking of gatch feedstock.

(27) During the hydrogenation reaction in the present invention, the amount of the used hydrogen gas is the stoichiometric hydrogen consumption amount plus the amount of dissolved hydrogen amount slightly more than that of the system. The section for reaction is not provided with a hydrogen circulating system, the hydrogen gas needed for the hydrogenation reaction of the fresh raw material is provided by the dissolved hydrogen entrained into the reaction system from the circulation of a large amount of liquid-phase product and the dissolved hydrogen supplemented by the hydrogen gas. Due to the reuse of the hydrogenated product, the activity stability of the catalyst can be maintained. This method is advantageous in that the influence of the wetting factor of the catalyst and the influence of H.sub.2S and NH.sub.3 in the circulating hydrogen can be eliminated; due to a high specific heat capacity of the circulated oil, it is possible to reduce the temperature rise in the reactor and improve the utilization efficiency of the catalyst.