A high-temperature and high-pressure gas compressor lubricating oil composition and preparation method thereof

Abstract

The present invention provides a high-temperature and high-pressure gas compressor lubricating oil composition, comprising the following components in parts by weight: 64.5 to 97.37 parts of polyethylene glycol ether, 2 to 20 parts of ester oil, 0.5 to 8 parts of antioxidant, 0.1 to 5 parts of extreme pressure anti-wear agent, 0.02 to 2 parts of corrosion inhibitor, and 0.01 to 0.5 parts of defoaming agent. The present invention also discloses a preparation method of the high-temperature and high-pressure gas compressor lubricating oil composition. The present invention uses polyethylene glycol ether and ester oil as base oils, and adds antioxidants, extreme pressure anti-wear agents, corrosion inhibitors, and defoaming agents to prepare a lubricating oil composition, which has excellent thermal stability and chemical stability and high anti-wear performance; at the same time, the compressor lubricating oil composition disclosed by the present invention has very low solubility in hydrocarbon gases, and is suitable for lubrication and protection of compressors that compress various hydrocarbon gases (such as natural gas, gas, liquefied gas, refinery tail gas, ethylene, propylene, etc.).

Description

Technical Field

[0001] This invention relates to the field of gas compressor lubricating oil technology, specifically a high-temperature, high-pressure gas compressor lubricating oil composition and its preparation method. Background Technology

[0002] A gas compressor is a power device that converts mechanical energy into gas pressure energy. It is commonly used to provide gas power for pneumatic tools and is also frequently used in industries such as petrochemicals, drilling, and metallurgy to pressurize and transport media such as oxygen, hydrogen, ammonia, natural gas, coke oven gas, and inert gases.

[0003] Industrially widely used gas compressors can be broadly classified into two categories based on their operating principles: positive displacement and dynamic. Positive displacement compressors work by using movable container walls to reduce the volume of the enclosed working space occupied by the gas, thereby bringing gas molecules closer together and increasing gas pressure. Structurally, positive displacement gas compressors are further subdivided into piston, screw, scroll, and rotary types. Dynamic gas compressors work by propelling gas molecules to a high speed through mechanical high-speed rotation, then decelerating them to convert kinetic energy into pressure energy. Dynamic gas compressors are further divided into centrifugal and axial flow types. The main components of a gas compressor system requiring oil lubrication are three: bearings, rotor teeth, and a capacity control mechanism.

[0004] For lubricating oils used in high-temperature, high-pressure gas compressors, the following requirements should be met:

[0005] (1) Excellent wear resistance, protecting the structure from wear during long-term use.

[0006] (2) Excellent thermal stability and chemical stability, the oil remains stable under high temperature, high pressure and high load conditions.

[0007] (3) Minimal tendency for gum and residual carbon.

[0008] (4) Excellent protective performance, protecting equipment from corrosion.

[0009] (5) It has low solubility in gases, which can effectively prevent it from being diluted by gases.

[0010] (6) Excellent anti-foaming properties: gas foam can be quickly separated from lubricating oil, avoiding accumulation and affecting the normal operation of the gas compressor.

[0011] Currently, most lubricating oils used in gas compressors have an operating temperature range of -25 to 150°C. They are mostly made from refined mineral oil or polyalphaolefin base oils, with a smaller number made from polyether base oils. There are very few reports of gas compressor lubricating oils designed for higher temperature environments. Common gas compressor lubricating oils on the market mainly have the following problems:

[0012] 1) Poor high-temperature performance; the lubricating oil is not suitable for temperatures of 150℃ and above.

[0013] 2) Insufficient anti-wear performance, requiring frequent oil changes;

[0014] 3) It is easily diluted by gases and gradually fails to meet usage requirements;

[0015] 4) Insufficient ability to resist foam aggregation, and foam does not dissipate quickly enough. Summary of the Invention

[0016] To address the aforementioned shortcomings of existing technologies, this invention provides a high-temperature, high-pressure gas compressor lubricating oil composition and its preparation method.

[0017] The first objective of this invention is achieved through the following technical solution:

[0018] A high-temperature, high-pressure gas compressor lubricating oil composition comprising the following components in parts by weight:

[0019]

[0020] Furthermore, the aforementioned polyethylene glycol ether is a linear polymer obtained by ring-opening homopolymerization or copolymerization of ethylene oxide, propylene oxide, and butane oxide as raw materials under the action of a catalyst. Its technical parameters are as follows: kinematic viscosity at 40°C is 32–460 mm³ / s. 2 / s, open flash point ≥200℃, pour point ≤-24℃, colorless and transparent.

[0021] Furthermore, the ester oil is one or more of diesters or polyol esters, and the technical parameters of the ester oil are as follows: kinematic viscosity at 40°C is 8-150 mmHg. 2 / s, open flash point ≥180℃, pour point ≤-24℃.

[0022] Furthermore, the diester includes dioctyl sebacate and dinonyl sebacate, and the polyol ester includes trimethylolpropane ester and pentaerythritol ester.

[0023] Furthermore, the antioxidant is a combination of two or more of N-phenyl-α-naphthylamine (T531), N-phenyl-β-naphthylamine, octylbutyldiphenylamine (T557), diisooctyldiphenylamine, and 2,2,4-trimethyl-1,2-dihydroquinoline polymer (TMQ).

[0024] Furthermore, the anti-wear agent is one or a combination of several of the following: zinc dialkyl dithiophosphate (T202), dibutyl phosphite (T304), tricresyl phosphate (T306), and triphenyl thiophosphate (T309).

[0025] Furthermore, the defoamer is one or a combination of several of the following: non-silicone defoamer, silicone defoamer, polyether defoamer, or polyether-modified silicone defoamer.

[0026] Furthermore, all the defoamers mentioned are transparent, liquid types with a kinematic viscosity of 1–5000 mmHg at 40°C. 2 / s.

[0027] The second objective of this invention is achieved through the following technical solution:

[0028] A method for preparing the above-mentioned high-temperature and high-pressure gas compressor lubricating oil composition includes the following steps:

[0029] 1) First, thoroughly clean the reaction vessel and other preparation tools used to avoid the introduction of other impurities;

[0030] 2) Add the base oil and antioxidant to the reactor, start stirring and heating, seal the lid and draw a vacuum, raise the temperature to 130-135℃, keep the temperature constant and draw a vacuum to dehydrate for 2 hours, with a vacuum degree ≥-0.08Mpa; after the constant temperature is completed, turn on the cooling water to cool down to 80±5℃, close the vacuum valve, open the lid and add the anti-wear agent, corrosion inhibitor and defoamer, close the lid and turn on the filter to circulate for 30 minutes;

[0031] 3) After the cycle time is up, the compressor lubricating oil composition is obtained by filtering and discharging the material.

[0032] This invention has the following inventive features:

[0033] 1. The high-temperature and high-pressure gas compressor lubricating oil composition provided by the present invention uses polyethylene glycol ether and ester oil as base oils and adds compound antioxidants. It has excellent thermal stability and chemical stability, and its open flash point can reach above 290°C. At the same time, it has very low tendency to produce gum and residual carbon, and can be used in high-temperature environments.

[0034] 2. The high-temperature, high-pressure gas compressor lubricating oil composition provided by this invention uses a base oil with a kinematic viscosity of 32-460 mmHg at 40°C. 2 / s of polyethylene glycol ether and a small amount of kinematic viscosity of 8-150 mm at 40°C 2The ester-based oil, with a low solubility for hydrocarbon gases, effectively avoids dilution by hydrocarbon gases and is suitable for compressors that compress various hydrocarbon gases (such as natural gas, coal gas, liquefied petroleum gas, refinery tail gas, ethylene, propylene, etc.). Using a 1000ml graduated cylinder, 200ml of the high-temperature, high-pressure gas compressor lubricating oil provided by this invention was tested. At 24°C, natural gas was introduced at a flow rate of 100±5mL / min using a gas diffuser for 15 minutes. The viscosity reduction rate of the lubricating oil (considered as the dilution rate of hydrocarbon gases) was less than 5%, while under the same conditions, the viscosity reduction rate of compressor oils using mineral oil and polyalphaolefin as base oils was more than 15%.

[0035] 3. The high-temperature and high-pressure gas compressor lubricating oil composition provided by this invention, with the addition of compound anti-wear agent, has excellent anti-wear performance. The maximum non-seize load on the four-ball tester reaches more than 135kg, and the wear scar diameter is within 0.33mm at 40kg for 30min. At the same time, the protective performance is also excellent, and the copper sheet corrosion under the condition of 100℃ for 24h can reach level 1a. Detailed Implementation

[0036] The technical solutions of the present invention will be described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the following embodiments.

[0037] Example 1

[0038] 92 parts with a kinematic viscosity of 150 mmHg at 40℃ were used. 2 Approximately 1 / s of polyethylene glycol ether, 5 parts of trimethylolpropane oleate, 1.5 parts of N-phenyl-β-naphthylamine, and 0.9 parts of 2,2,4-trimethyl-1,2-dihydroquinoline polymer were added to a reactor. Stirring was started, the reactor was sealed, and a vacuum was applied. The temperature was raised to 130–135°C, and the mixture was kept at this temperature under vacuum for 2 hours to dehydrate it, with a vacuum degree ≥-0.08 MPa. After the constant temperature period, cooling water was turned on to lower the temperature to 80±5°C. The vacuum valve was closed, and the reactor lid was opened. 0.3 parts of triphenyl thiophosphate, 0.2 parts of dibutyl phosphite, 0.05 parts of benzotriazole derivative, 0.03 parts of silicone defoamer, and 0.02 parts of polyether defoamer were added. The reactor lid was closed, and the mixture was circulated through a filter for 30 minutes. After filtration, the high-temperature, high-pressure gas compressor lubricating oil composition was obtained.

[0039] Example 2

[0040] 89 parts with a kinematic viscosity of 100 mm at 40℃ 2Polyethylene glycol ether (approximately 1 / 2 ppm), 6 parts dioctyl sebacate, 2 parts N-phenyl-α-naphthylamine, and 1.5 parts diisooctyl diphenylamine were added to a reaction vessel. Stirring was started, the vessel was sealed, and a vacuum was applied. The temperature was raised to 130–135°C, and the mixture was kept at this temperature under vacuum for 2 hours to dehydrate it, maintaining a vacuum level ≥ -0.08 MPa. After the vacuum period, cooling water was turned on to lower the temperature to 80±5°C. The vacuum valve was closed, and the vessel lid was opened. 0.2 parts triphenyl thiophosphate, 0.2 parts zinc dialkyl dithiophosphate, 1 part tricresyl phosphate, 0.03 parts benzotriazole derivative, 0.02 parts thiadiazole derivative, 0.03 parts silicone defoamer, and 0.02 parts non-silicone defoamer were added. The vessel lid was closed, and the mixture was circulated through a filter for 30 minutes. After filtration, the final product was obtained as a high-temperature, high-pressure gas compressor lubricating oil composition.

[0041] Example 3

[0042] 85 parts with a kinematic viscosity of 68 mmHg at 40℃ 2 Approximately 7.5 parts of polyethylene glycol ether, 4 parts of pentaerythritol oleate, 2.2 parts of octylbutyldiphenylamine, and 2.2 parts of 2,2,4-trimethyl-1,2-dihydroquinoline polymer were added to a reactor. Stirring was started, the reactor was sealed, and a vacuum was applied. The temperature was raised to 130–135°C, and the mixture was kept at this temperature under vacuum for 2 hours to dehydrate it, with a vacuum degree ≥ -0.08 MPa. After the constant temperature period, cooling water was turned on to lower the temperature to 80±5°C. The vacuum valve was closed, and the reactor lid was opened. 0.5 parts of tricresyl phosphate, 0.7 parts of dibutyl phosphite, 0.07 parts of benzotriazole derivative, 0.02 parts of silicone defoamer, and 0.01 parts of non-silicone defoamer were added. The reactor lid was closed, and the mixture was circulated through a filter for 30 minutes. After filtration, the high-temperature, high-pressure gas compressor lubricating oil composition was obtained.

[0043] Example 4

[0044] 90 parts with a kinematic viscosity of 150 mm at 40℃ 2 Add approximately 1 part polyethylene glycol ether, 5 parts pentaerythritol oleate, 3 parts N-phenyl-α-naphthylamine, and 2.8 parts 2,2,4-trimethyl-1,2-dihydroquinoline polymer to a reactor. Start stirring, seal the reactor, and apply vacuum. Heat to 130–135°C, maintain the temperature under vacuum for 2 hours to dehydrate, achieving a vacuum degree ≥-0.08 MPa. After the temperature is maintained, cool the reactor to 80±5°C, close the vacuum valve, open the reactor lid, and add 1 part triphenyl thiophosphate, 2 parts tricresyl phosphate, 0.35 parts thiadiazole derivative, 0.02 parts silicone defoamer, and 0.03 parts non-silicone defoamer. Close the reactor lid, circulate the mixture through a filter for 30 minutes, and then filter again to obtain the high-temperature, high-pressure gas compressor lubricating oil composition.

[0045] Example 5

[0046] 91.5 parts with a kinematic viscosity of 220 mmHg at 40℃ 2Add approximately 1 part polyethylene glycol ether, 3 parts trimethylolpropane oleate, 2 parts N-phenyl-α-naphthylamine, and 1 part octylbutyldiphenylamine to a reaction vessel. Start stirring, seal the vessel, and apply vacuum. Heat to 130–135°C, maintain the temperature under vacuum for 2 hours to dehydrate, achieving a vacuum degree ≥ -0.08 MPa. After the temperature is maintained, cool the vessel to 80±5°C, close the vacuum valve, open the vessel lid, and add 0.8 parts triphenyl thiophosphate, 1 part tricresyl phosphate, 0.55 parts dibutyl phosphite, 0.1 parts benzotriazole, 0.01 parts silicone defoamer, and 0.04 parts polyether-modified silicone defoamer. Close the vessel lid, circulate the mixture through a filter for 30 minutes, and then filter again to obtain the high-temperature, high-pressure gas compressor lubricating oil composition.

[0047] Example 6

[0048] 92.36 parts with a kinematic viscosity of 100 mmHg at 40℃ 2 Add approximately 1 part polyethylene glycol ether, 3 parts dinonyl sebacate, 2 parts diisooctyl diphenylamine, and 1 part N-phenyl-α-naphthylamine to a reaction vessel. Start stirring, seal the vessel, and apply vacuum. Heat to 130–135°C, maintain the temperature under vacuum for 2 hours to dehydrate, achieving a vacuum degree ≥-0.08 MPa. After the temperature is maintained, cool the vessel to 80±5°C, close the vacuum valve, open the vessel lid, and add 1 part tricresyl phosphate, 0.2 parts zinc dialkyl dithiophosphate, 0.2 parts benzotriazole derivative, 0.2 parts thiadiazole derivative, 0.02 parts silicone defoamer, and 0.02 parts polyether defoamer. Close the vessel lid, start the filter, and circulate the mixture for 30 minutes. Filter the mixture again to obtain the high-temperature, high-pressure gas compressor lubricating oil composition.

[0049] Example 7

[0050] 84.05 parts with a kinematic viscosity of 320 mmHg at 40℃ 2 Polyethylene glycol ether (approximately 10 parts), pentaerythritol oleate (10 parts), N-phenyl-α-naphthylamine (2 parts), and octylbutyldiphenylamine (1.8 parts) were added to a reaction vessel. Stirring was started, the vessel was sealed, and a vacuum was applied. The temperature was raised to 130–135°C, and the mixture was kept at this temperature under vacuum for 2 hours to dehydrate it, maintaining a vacuum level ≥ -0.08 MPa. After the vacuum period, cooling water was turned on to lower the temperature to 80±5°C. The vacuum valve was closed, and the vessel lid was opened. 0.8 parts of triphenyl thiophosphate, 1 part of tricresol phosphate, 0.2 parts of dibutyl phosphite, 0.1 parts of benzotriazole derivative, 0.02 parts of silicone defoamer, and 0.03 parts of non-silicone defoamer were added. The vessel lid was closed, and the mixture was circulated through a filter for 30 minutes. After filtration, the final product was obtained as a high-temperature, high-pressure gas compressor lubricating oil composition.

[0051] The technical parameters of the high-temperature and high-pressure gas compressor lubricating oil compositions obtained in Examples 1 to 7 are shown in Table 1 below:

[0052] Table 1

[0053]

[0054]

[0055] As shown in the table above, the high-temperature and high-pressure gas compressor lubricating oil composition prepared by this invention not only meets the general requirements for gas compressor use, but also has a unique open flash point higher than 290℃, exhibiting excellent high-temperature thermal stability and meeting the requirements of relatively harsh high-temperature operating environments. Simultaneously, while meeting corrosion resistance requirements, it also possesses excellent wear resistance, with a maximum non-seize load value exceeding 135kg using the four-ball method, and a wear scar diameter not exceeding 0.33mm, effectively protecting equipment from wear during long-term use. More importantly, it has low solubility in hydrocarbon gases, effectively preventing dilution by hydrocarbon gases, making it suitable for the lubrication and protection of compressors that compress various hydrocarbon gases (such as natural gas, coal gas, liquefied petroleum gas, refinery tail gas, ethylene, propylene, etc.).

[0056] The high-temperature, high-pressure gas compressor lubricating oil composition of this invention mainly improves high-temperature performance, anti-wear performance, and low solubility of hydrocarbon gases through the following aspects:

[0057] 1) Two or more antioxidants of N-phenyl-α-naphthylamine (T531), N-phenyl-β-naphthylamine, octylbutyldiphenylamine (T557), diisooctyldiphenylamine, and 2,2,4-trimethyl-1,2-dihydroquinoline polymer (TMQ) are selected and used in combination. The synergistic effect of multiple antioxidants greatly improves the high-temperature performance of the lubricating oil composition, which greatly enhances the high-temperature performance of the polyethylene glycol ether and synthetic ester base oil, which already have good high-temperature performance, and raises the flash point of the lubricating oil composition to above 290°C.

[0058] 2) Polyethylene glycol ether is selected as the main base oil. Its solubility for hydrocarbon gases is extremely low compared with mineral oil and polyalphaolefin. Under the condition of 24°C, natural gas is introduced at a flow rate of 100±5mL / min for 15min using a gas diffuser. The viscosity reduction rate of the lubricating oil of the present invention (considered as the dilution rate of hydrocarbon gases) is less than 5%.

[0059] 3) Select one or a combination of several of the following anti-wear agents: zinc dialkyl dithiophosphate (T202), dibutyl phosphite (T304), tricresyl phosphate (T306), and triphenyl thiophosphate (T309). These anti-wear agents are soluble in polyethylene glycol ether, and the synergistic effect of adding two or more is better than that of a single agent. In addition, polyethylene glycol ether and synthetic ester are selected as base oils, which have a low coefficient of friction. Finally, the lubricating oil of this invention achieves a maximum non-seizure load of over 135 kg in a four-ball test, while the wear scar diameter is within 0.33 mm at 40 kg for 30 min.

[0060] The lubricating oil composition of this invention, using polyethylene glycol ether and synthetic ester as base oils and adding composite antioxidants, anti-wear extreme pressure agents, corrosion inhibitors, and defoamers, exhibits excellent thermal stability and chemical stability, extremely low gum and carbon residue tendency, good low-temperature performance, and excellent anti-wear properties. Simultaneously, it has very low solubility in hydrocarbon gases, effectively preventing dilution by hydrocarbon gases and providing excellent protective performance. It is suitable for compressors that compress various hydrocarbon gases (such as natural gas, coal gas, liquefied petroleum gas, refinery tail gas, ethylene, propylene, etc.).

[0061] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A high-temperature and high-pressure gas compressor lubricating oil composition, characterized in that: The composition comprises the following components in parts by weight: 64.5-97.37 parts of polyethylene glycol ether; 2-20 parts of ester oil; 0.5-8 parts of antioxidant; 0.1-5 parts of anti-wear agent; 0.02-2 parts of corrosion inhibitor; 0.01-0.5 parts of defoaming agent; The polyethylene glycol ether is a linear polymer obtained by homopolymerization or copolymerization of ethylene oxide, propylene oxide and butylene oxide as raw materials under the action of a catalyst. The technical parameters of the polyethylene glycol ether are as follows: the kinematic viscosity at 40°C is 32~460mm 2 / s, open flash point ≥200℃, pour point ≤-24℃, colorless and transparent; The ester oil is one or a combination of diester and polyol ester. The technical parameters of the ester oil are as follows: 40°C kinematic viscosity is 8~150mm 2 / s, open flash point ≥180℃, pour point ≤-24℃.

2. The high-temperature and high-pressure gas compressor lubricating oil composition according to claim 1, characterized in that: The diesters include dioctyl sebacate and dinonyl sebacate, and the polyol esters include trimethylolpropane ester and pentaerythritol ester.

3. The high-temperature and high-pressure gas compressor lubricating oil composition according to claim 1, characterized in that: The antioxidant is a combination of two or more of N-phenyl-α-naphthylamine, N-phenyl-β-naphthylamine, octylbutyldiphenylamine, diisooctyldiphenylamine and 2,2,4-trimethyl-1,2-dihydroquinoline polymer.

4. The high-temperature and high-pressure gas compressor lubricating oil composition according to claim 1, characterized in that: The anti-wear agent is one or a combination of dialkyl zinc dithiophosphate, dibutyl phosphite, tricresyl phosphate and triphenyl thiophosphate.

5. The high-temperature and high-pressure gas compressor lubricating oil composition according to claim 1, characterized in that: The corrosion inhibitor is one or a combination of benzotriazole, benzotriazole derivatives and thiadiazole derivatives.

6. The high-temperature and high-pressure gas compressor lubricating oil composition according to claim 1, characterized in that: The defoamer is a combination of two or more of a non-silicon defoamer, an organosilicon defoamer, a polyether defoamer or a polyether-modified organosilicon defoamer.

7. The high-temperature and high-pressure gas compressor lubricating oil composition according to claim 6, characterized in that: The defoamers are all transparent, liquid, and have a kinematic viscosity of 1~5000mm at 40°C. 2 / s.

8. A method for preparing a high-temperature and high-pressure gas compressor lubricating oil composition according to any one of claims 1 to 7, characterized in that: 1) Clean the reactor and other preparation tools used to avoid mixing with other impurities; 2) Add base oil and antioxidant into the reactor, start stirring and heating, cover and evacuate, raise the temperature to 130~135℃, and dehydrate by vacuum at constant temperature for 2h, with the vacuum degree ≥-0.08Mpa; after the constant temperature is over, open the cooling water to cool down to 80±5℃, close the vacuum valve, open the reactor cover to add anti-wear agent, corrosion inhibitor, defoaming agent, close the reactor cover, and start the filter to circulate for 30min; 3) After the circulation time is up, the high-temperature and high-pressure gas compressor lubricating oil composition is obtained by filtering the material.

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