Production device and method of aviation hydraulic oil low-condensation base oil
By combining low-pressure hydrorefining and molecular sieve dewaxing, the high cost of high-pressure hydrorefining has been solved, producing low-sulfur, low-aromatic, and low-pour-point base oils. This achieves low investment, high stability, and adaptability to ultra-low temperature environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- PETROCHINA CO LTD
- Filing Date
- 2024-12-30
- Publication Date
- 2026-06-30
AI Technical Summary
The existing low-pour-point base oil production process using high-pressure hydrorefining-isomeric pour point depressant technology has high investment costs, is difficult to implement, and produces products with high aromatic content.
The process employs a low-pressure hydrorefining-molecular sieve dewaxing combined process, including a hydrorefining module, a fine fractionation module, and a molecular sieve dewaxing module. It uses MHDS-8B and MH-6C catalysts, with a production process temperature ≤300℃ and a pressure ≤5MPa, and removes n-alkanes at a deep depth through molecular sieves.
It produces low-pour-point base oil with less than 1% aromatics and less than 1 mg/kg sulfur content. It requires little investment, is easy to implement, and produces base oil with good stability, low pour point, and adaptability to ultra-low temperature environments.
Smart Images
Figure CN122302939A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of petroleum processing technology, and specifically relates to a production apparatus and method for low-pour-point base oil of aviation hydraulic oil. Background Technology
[0002] Low-pour-point base oils are special base oils used in low-temperature environments. They have a lower pour point (i.e., a lower minimum temperature at which they can remain fluid) than ordinary base oils, allowing them to maintain good fluidity even at low temperatures and thus perform their lubrication and energy transfer functions normally. The base oil production process mainly includes fine fractionation, base oil refining (including acid-base refining, clay refining, and hydrorefining), and base oil pour point depressing. Currently, the production of low-aromatic and low-pour-point base oils mainly adopts high-pressure hydrotreating and isomerization pour point depressing technologies (reaction pressure approximately 10 MPa). Due to the high pressure level, the construction or modification costs are high, and implementation is difficult.
[0003] Chinese Invention Patent, Title: A Method for Preparing Aviation Hydraulic Oil Base Oil Containing Appropriate Aromatic Hydrocarbons, Application No.: CN202310037795, Application Date: January 9, 2023, Applicant: Shandong Jingbo New Energy Holding Development Co., Ltd., Legal Status: Substantive Examination Effective. Technical Solution: Employs a hydrorefining-hydrodewaxing-precision fractionation production process, the product mainly being a low-pour-point base oil with 7-10% aromatic hydrocarbons. Chinese Invention Patent, Title: A Method for Preparing Aviation Hydraulic Oil Base Oil, Application No.: CN201611115621.X, Application Date: December 7, 2016, Applicant: China National Petroleum Corporation, Legal Status: Invention Patent Granted. Employs a hydrorefining-hydrodewaxing-precision fractionation production process. The product mainly being a low-pour-point base oil with 9% aromatic hydrocarbons. The above two patents mainly involve high-pressure hydrorefining-isomeric dewaxing process technology, the products have a high aromatic hydrocarbon content, and the production process involves high investment. Summary of the Invention
[0004] To address the aforementioned problems, the purpose of this invention is to provide a production apparatus and method for low-pour-point base oil in aviation hydraulic fluid. This invention utilizes a combined process of "low-pressure hydrorefining-molecular sieve dewaxing" to produce a low-sulfur, low-aromatic, and low-pour-point base oil with less than 1% aromatics. The production method has the advantages of low investment and ease of implementation.
[0005] The technical solution of this invention is as follows: a production apparatus for low-pour-point base oil of aviation hydraulic fluid, comprising a hydrorefining module, a fine fractionation module, and a molecular sieve dewaxing module connected in sequence. The hydrorefining module includes a feed pump, a first heat exchanger, a second heat exchanger, a first heating furnace, and a first-stage desulfurization reactor connected in sequence. The output end of the second heat exchanger is also connected to an air cooler and a second-stage aromatics hydrogenation reactor. The output end of the second-stage aromatics hydrogenation reactor is connected to the first heat exchanger. The output end of the feed pump is connected to the first heat exchanger. The output end of the first heat exchanger is also connected to a high-pressure separator and a circulating hydrogen compressor. ZnO desulfurizing agent and fresh hydrogen, the output end of the circulating hydrogen compressor is connected to the input end of the first heat exchanger, the fine fractionation module includes a fractionation tower, the lower part of the fractionation tower is connected to a second heating furnace, the top of the fractionation tower is connected to a stripping tower, the bottom of the stripping tower is connected to a third heat exchanger, the output end of the third heat exchanger is connected to a first separating tank, the molecular sieve dewaxing module includes a third heating furnace, an adsorption tower, a fourth heat exchanger and a second separating tank connected in sequence, the oil phase output end of the high-pressure separator is connected to the input end of the fractionation tower, and the output end of the first separating tank is connected to the input end of the third heating furnace.
[0006] An apparatus and method for producing low-pour-point base oil for aviation hydraulic fluid, using the apparatus described above, includes the following steps: S1: Hydrorefining of oil products. The specific process is as follows: the feedstock oil is hydrodesulfurized and dearomatized in a two-stage series. In the first stage, a desulfurization catalyst is used to convert organic sulfides into H2S. The generated H2S then reacts with the desulfurization catalyst to generate sulfide XS. In the second stage, a dearomatization catalyst is used to hydrogenate and saturate the aromatics in the feedstock oil into cycloalkanes, producing hydrorefined oil with aromatics <1% and sulfur content <1mg / kg. S2: Fine distillation of oil products, the specific process is: hydrorefined oil is finely distilled in a distillation tower to obtain distillate oil at 230℃~280℃; S3: Molecular sieve dewaxing, the specific process is as follows: the 230℃~280℃ distillate oil is deeply dewaxed by 5A molecular sieve to remove n-alkanes, the oil pour point is reduced to below -75℃, and low pour point and low aromaticity aviation hydraulic oil base oil is produced.
[0007] In step S1, the desulfurization catalyst is specifically MHDS-8B produced by Shanxi Coal Chemistry Research Institute, and the dearomatization catalyst is specifically MH-6C produced by Shanxi Coal Chemistry Research Institute.
[0008] The temperature and pressure of the hydrorefining process in step S1 are ≤300℃ and ≤5MPa.
[0009] In step S2, during the fine fractionation of oil, the outlet temperature of the second heating furnace ranges from 250 to 290°C, the top temperature of the fractionation tower ranges from 145 to 210°C, the bottom temperature of the fractionation tower ranges from 240 to 265°C, and the side stream temperature of the fractionation tower ranges from 180 to 215°C.
[0010] In step S3, during the molecular sieve dewaxing process, the outlet temperature of the third heating furnace ranges from 370 to 425°C, the bed temperature of the adsorption tower reactor ranges from 255 to 365°C, and the desorption steam pressure ranges from 0.05 to 0.35 MPa.
[0011] The technical advantages of this invention are as follows: 1. This invention uses a combined process of "low-pressure hydrorefining - molecular sieve dewaxing" to produce low-sulfur, low-aromatic, and low-pour-point base oil with less than 1% aromatics. The production method has the advantages of low investment and ease of implementation. 2. The reaction temperature and pressure of this invention's production process are low. The hydrorefining process temperature is ≤300℃ and the pressure is ≤5MPa, while the mainstream high-pressure hydrorefining pressure is 8-10MPa, which is only half of that of high-pressure hydrorefining. The investment cost for new construction or renovation is much lower than that of high-pressure hydrorefining units. 3. The base oil produced by this invention has low aromatic and sulfur content. The base oil has an aromatic content of <1% and a sulfur content of <1mg / kg, a high degree of refining, better stability, and can better meet increasingly stringent environmental and health requirements. 4. The base oil produced by this invention has a low pour point. The base oil produced by this method has a pour point of <-75℃, and the low-temperature performance of the product is better suited to the requirements of ultra-low temperature operating environments.
[0012] The following will provide further explanation in conjunction with the accompanying drawings. Attached Figure Description
[0013] Figure 1 This is a process flow diagram of the hydrogenation refining module in an embodiment of the present invention.
[0014] Figure 2 This is a process flow diagram of the fine fractionation module in an embodiment of the present invention.
[0015] Figure 3 This is a process flow diagram of the molecular sieve dewaxing module in an embodiment of the present invention.
[0016] Figure labels: 1-Raw material pump, 2-New hydrogen, 3-First heat exchanger, 4-Second heat exchanger, 5-First heating furnace, 6-First stage desulfurization reactor, 7-Air cooler, 8-Second stage aromatics hydrogenation reactor, 9-High pressure separator, 10-Circulating hydrogen compressor, 11-ZnO desulfurizing agent, 12-Second heating furnace, 13-Fracturing tower, 14-Stripping tower, 15-Third heat exchanger, 16-First separating tank, 17-Third heating furnace, 18-Adsorption tower, 19-Fourth heat exchanger, 20-Second separating tank. Detailed Implementation Example 1
[0017] like Figures 1-3 As shown, a production apparatus for low-pour-point base oil in aviation hydraulic fluid includes a hydrorefining module, a fine fractionation module, and a molecular sieve dewaxing module connected in sequence. The hydrorefining module includes a feedstock pump 1, a first heat exchanger 3, a second heat exchanger 4, a first heater 5, and a first-stage desulfurization reactor 6 connected in sequence. The output end of the second heat exchanger 4 is also connected to an air cooler 7 and a second-stage aromatics hydrorefining reactor 8. The output end of the second-stage aromatics hydrorefining reactor 8 is connected to the first heat exchanger 3. The output end of the feedstock pump 1 is connected to the first heat exchanger 3. The output end of the first heat exchanger 3 is also connected to a high-pressure separator 9, a circulating hydrogen compressor 10, a ZnO desulfurizing agent 11, and fresh hydrogen 2. The output end of the cyclic hydrogen compressor 10 is connected to the input end of the first heat exchanger 3. The fine fractionation module includes a fractionation column 13, the lower part of which is connected to a second heater 12. The top of the fractionation column 13 is connected to a stripping column 14, and the bottom of the stripping column 14 is connected to a third heat exchanger 15. The output end of the third heat exchanger 15 is connected to a first separator 16. The molecular sieve dewaxing module includes a third heater 17, an adsorption column 18, a fourth heat exchanger 19, and a second separator 20 connected in sequence. The oil phase output end of the high-pressure separator 9 is connected to the input end of the fractionation column 13, and the output end of the first separator 16 is connected to the input end of the third heater 17. Example 2
[0018] A method for producing a low-pour-point base oil for aviation hydraulic fluid, using the production apparatus for a low-pour-point base oil for aviation hydraulic fluid as described above, includes the following steps: S1: Hydrorefining of oil products. The specific process is as follows: the feedstock oil is hydrodesulfurized and dearomatized in a two-stage series. In the first stage, a desulfurization catalyst is used to convert organic sulfides into H2S. The generated H2S then reacts with the desulfurization catalyst to generate sulfide XS. In the second stage, a dearomatization catalyst is used to hydrogenate and saturate the aromatics in the feedstock oil into cycloalkanes, producing hydrorefined oil with aromatics <1% and sulfur content <1mg / kg. S2: Fine distillation of oil products, the specific process is: hydrorefined oil is finely distilled in a distillation tower to obtain distillate oil at 230℃~280℃; S3: Molecular sieve dewaxing, the specific process is as follows: the 230℃~280℃ distillate oil is deeply dewaxed by 5A molecular sieve to remove n-alkanes, the oil pour point is reduced to below -75℃, and low pour point and low aromaticity aviation hydraulic oil base oil is produced.
[0019] In step S1, the desulfurization catalyst is specifically MHDS-8B produced by Shanxi Coal Chemistry Research Institute, and the dearomatization catalyst is specifically MH-6C produced by Shanxi Coal Chemistry Research Institute.
[0020] The temperature and pressure of the hydrorefining process in step S1 are ≤300℃ and ≤5MPa.
[0021] In step S2, during the fine fractionation of the oil, the outlet temperature of the second heating furnace 12 ranges from 250 to 290°C, the top temperature of the fractionation tower 13 ranges from 145 to 210°C, the bottom temperature of the fractionation tower 13 ranges from 240 to 265°C, and the side stream temperature of the fractionation tower 13 ranges from 180 to 215°C.
[0022] In step S3, during the molecular sieve dewaxing process, the outlet temperature of the third heating furnace 17 ranges from 370 to 425°C, the temperature of the reactor bed in the adsorption tower 18 ranges from 255 to 365°C, and the desorption steam pressure ranges from 0.05 to 0.35 MPa. Example 3
[0023] The production method of low-pour-point base oil for aviation hydraulic oil as described in Example 2, using the production apparatus of low-pour-point base oil for aviation hydraulic oil as described in Example 1, is as follows: S1: Oil hydrorefining, specifically the process involves hydrodesulfurizing and dearomatizing the feedstock oil in a two-stage series process. The first-stage hydrorefining reaction is carried out at a temperature of 280℃, a pressure of 4.5 MPa, and a mass hourly space velocity of 1.2 h⁻¹. -1 The hydrogen-to-oil volume ratio was 400; the two-stage hydrogenation reaction temperature was 200℃, the pressure was 4.5MPa, and the mass hourly space velocity (HHSV) was 0.7h. -1 Under the condition of a hydrogen-to-oil volume ratio of 400, the refined oil produced has aromatics <1%, sulfur content <1mg / kg, and freezing point <-75℃. S2: Fine distillation of oil products. The specific process is as follows: hydrorefined oil is finely distilled in a distillation tower to obtain distillate oil at 230℃~280℃. The specific process parameters are shown in Table 1. Table 1 Key process parameters for fine fractionation S3: Molecular sieve dewaxing. The specific process is as follows: the distillate oil at 230℃~280℃ is deeply dewaxed by 5A molecular sieve to remove n-alkanes. The specific process parameters are shown in Table 2. The oil pour point is reduced to below -75℃. The specific parameters are shown in Table 3. Low pour point and low aromaticity aviation hydraulic oil base oil is produced.
[0024] Table 2 Key process parameters for molecular sieve dewaxing The outlet temperature of the third heating furnace, ℃ 370～425 Adsorption tower reactor bed temperature, ℃ 255～365 Desorption steam pressure in adsorption tower, MPa 0.05～0.35 Table 3 Properties of Low Pour Point and Low Aromaticity Aviation Hydraulic Oil Base Oils Appearance S, mg / kg Alkylbenzene, % Freezing point, ℃ <![CDATA[Density, kg / m 3 > colorless 0.81 0.56 -78 822.1 This invention utilizes a combined process of "low-pressure hydrorefining - molecular sieve dewaxing" to produce low-sulfur, low-aromatic, and low-pour-point base oil with less than 1% aromatics. The production method offers advantages such as low investment and ease of implementation. The production process involves low reaction temperatures and pressures. The hydrorefining process operates at temperatures ≤300℃ and pressures ≤5MPa, while mainstream high-pressure hydrorefining pressures are 8-10MPa, representing only half the pressure of high-pressure hydrorefining. Therefore, the investment cost for new construction or retrofitting is significantly lower than for high-pressure hydrorefining units. The base oil produced by this invention has low aromatic and sulfur content and a low pour point. The base oil has an aromatic content <1%, a sulfur content <1mg / kg, and a pour point <-75℃, indicating a high degree of refining, better stability, and greater ability to meet increasingly stringent environmental and health requirements.
[0025] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.
Claims
1. A production apparatus for low-pour-point base oil in aviation hydraulic fluid, characterized in that: The system includes a hydrorefining module, a fine fractionation module, and a molecular sieve dewaxing module connected in sequence. The hydrorefining module includes a feed pump (1), a first heat exchanger (3), a second heat exchanger (4), a first heating furnace (5), and a first-stage desulfurization reactor (6) connected in sequence. The output end of the second heat exchanger (4) is also connected to an air cooler (7) and a second-stage aromatic hydrocarbon hydrogenation reactor (8). The output end of the second-stage aromatic hydrocarbon hydrogenation reactor (8) is connected to the first heat exchanger (3). The output end of the feed pump (1) is connected to the first heat exchanger (3). The output end of the first heat exchanger (3) is also connected to a high-pressure separator (9), a circulating hydrogen compressor (10), a ZnO desulfurizing agent (11), and fresh hydrogen (2). The output of the circulating hydrogen compressor (10) is... The fine fractionation module is connected to the input end of the first heat exchanger (3). The fractionation column (13) is connected to the second heating furnace (12) at the bottom. The stripping column (14) is connected to the top of the fractionation column (13). The third heat exchanger (15) is connected to the bottom of the stripping column (14). The output end of the third heat exchanger (15) is connected to the first liquid separator (16). The molecular sieve dewaxing module includes the third heating furnace (17), the adsorption column (18), the fourth heat exchanger (19), and the second liquid separator (20) connected in sequence. The oil phase output end of the high pressure separator (9) is connected to the input end of the fractionation column (13). The output end of the first liquid separator (16) is connected to the input end of the third heating furnace (17).
2. A method for producing low-pour-point base oil for aviation hydraulic fluid, using the production apparatus for low-pour-point base oil for aviation hydraulic fluid as described in claim 1, characterized in that: Includes the following steps: S1: Hydrorefining of oil products. The specific process is as follows: the feedstock oil is hydrodesulfurized and dearomatized in a two-stage series. In the first stage, a desulfurization catalyst is used to convert organic sulfides into H2S. The generated H2S then reacts with the desulfurization catalyst to generate sulfide XS. In the second stage, a dearomatization catalyst is used to hydrogenate and saturate the aromatics in the feedstock oil into cycloalkanes, producing hydrorefined oil with aromatics <1% and sulfur content <1mg / kg. S2: Fine distillation of oil products, the specific process is: hydrorefined oil is finely distilled in a distillation tower to obtain distillate oil at 230℃~280℃; S3: Molecular sieve dewaxing, the specific process is as follows: the 230℃~280℃ distillate oil is deeply dewaxed by 5A molecular sieve to remove n-alkanes, the oil pour point is reduced to below -75℃, and low pour point and low aromaticity aviation hydraulic oil base oil is produced.
3. The method for producing a low-pour-point base oil for aviation hydraulic fluid according to claim 2, characterized in that: In step S1, the desulfurization catalyst is specifically MHDS-8B produced by Shanxi Coal Chemistry Research Institute, and the dearomatization catalyst is specifically MH-6C produced by Shanxi Coal Chemistry Research Institute.
4. The method for producing a low-pour-point base oil for aviation hydraulic fluid according to claim 2, characterized in that: The temperature and pressure of the hydrorefining process in step S1 are ≤300℃ and ≤5MPa.
5. The method for producing a low-pour-point base oil for aviation hydraulic fluid according to claim 2, characterized in that: In the process of fine distillation of oil in step S2, the outlet temperature of the second heating furnace (12) is 250-290℃, the top temperature of the distillation tower (13) is 145-210℃, the bottom temperature of the distillation tower (13) is 240-265℃, and the side stream temperature of the distillation tower (13) is 180-215℃.
6. The method for producing a low-pour-point base oil for aviation hydraulic fluid according to claim 2, characterized in that: In step S3, during the molecular sieve dewaxing process, the outlet temperature of the third heating furnace (17) ranges from 370 to 425°C, the temperature of the reactor bed in the adsorption tower (18) ranges from 255 to 365°C, and the desorption steam pressure ranges from 0.05 to 0.35 MPa.