Compatible food-grade screw air compressor oil with long service life and low loss and preparation method of compatible food-grade screw air compressor oil

Abstract

The invention relates to the technical field of compressor oil, in particular to compatible long-service-life low-loss food-grade screw air compressor oil and a preparation method thereof. Comprising the following raw material components in parts by weight: 7-21 parts of hydrocarbon polymeric fluid containing ester functional groups, 6-18 parts of aromatic ester base oil, 2-9 parts of modified polyol ester, 3-8 parts of cyclohexane dibasic acid ester, 2-5 parts of poly-alpha-olefin, 2-5 parts of shaddock peel essential oil, 1-3 parts of propyl gallate, 3-6 parts of an antioxidant, 0.5-3 parts of an anti-wear reagent at extreme pressure, 0.05-0.2 part of a corrosion inhibitor, 0.05-0.5 part of an anti-rust agent, 0.05-0.2 part of a demulsifier and 0.01-0.2 part of a defoaming agent. The modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into polyol ester, and the mass ratio of the polyol ester to the diphenylamine to the naphthylamine to the phenolic ester is (3-5): (1-2): (1-2): 1.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of compressor oil, more particularly, it relates to a compatible long-life low-loss food-grade screw air compressor oil and a preparation method thereof. BACKGROUND

[0002] Air compressor is a machine that converts the power of a prime mover into gas pressure energy, and transports the pressure gas by increasing the gas pressure. It is a general equipment in modern equipment manufacturing industry. Screw air compressor is an important branch of compressor and belongs to positive displacement compressor. When the screw air compressor works, air enters the main machine through the air inlet filter, enters a pair of meshing male and female rotors which are parallel to each other, and the rotors change the air in the rotor tooth groove periodically to change the volume of the main machine, so as to realize the processes of air suction, sealing, compression and air exhaust. During the compression process, air is transported along the rotor axis from the air inlet side to the air outlet side, so as to complete the processes of air suction, sealing, compression and air exhaust.

[0003] Air compressor is widely used in mining, textile, metallurgy, machinery manufacturing, civil engineering, petroleum chemical industry and other industries, and is an indispensable key equipment for many enterprises in production and operation. In the field of energy storage which has emerged in recent years, compressed air energy storage is also the direction supported by the state.

[0004] However, the energy consumption problem of air compressor is increasingly prominent. At present, air compressor is one of the key energy consumption equipment of industrial enterprises. Energy saving of air compressor is of great significance. Air compressor manufacturers, various air compressor users and supporting service manufacturers pay more and more attention to energy saving index in the aspects of design, manufacture, use and maintenance, and reduce the energy consumption of air compressor through various ways. In the hardware link of air compressor, efforts are made to reduce the energy consumption index through variable speed drive device, heat recovery drive system, increase of power density, etc. In the operation and maintenance link, the emerging air compression station hosting project, contract energy management and other new operation modes also focus on energy saving and consumption reduction.

[0005] Under the background of energy saving and consumption reduction of air compressor industry, the energy saving and consumption reduction potential of air compressor lubricating oil has not been fully tapped. The oil injection screw air compressor oil on the market includes synthetic oil-PAO (polyalphaolefin), PAG (polyether) and POE (synthetic ester), etc. The high temperature performance and detergency of synthetic oil are good, the oil change period is also long, but the energy saving index is general; the compatibility is poor, and mixed use of lubricating oils with different formulas may cause additive incompatibility, causing oil gelling, precipitation or performance degradation, and even causing rotor jamming in severe cases. SUMMARY

[0006] The present application provides a compatible long-life low-loss food-grade screw air compressor oil and a preparation method thereof, which solves the above technical problems.

[0007] In a first aspect, the present application provides a compatible long-life low-loss food-grade screw air compressor oil, comprising the following raw material components by weight: ester group-containing hydrocarbon polymeric fluid 7-21 parts, aromatic ester base oil 6-18 parts, modified polyol ester 2-9 parts, cyclohexane diacid ester 3-8 parts, poly-alpha olefin 2-5 parts, naringin essential oil 2-5 parts, propyl gallate 1-3 parts, antioxidant 3-6 parts, extreme pressure anti-wear agent 0.5-3 parts, corrosion inhibitor 0.05-0.2 parts, anti-rust agent 0.05-0.5 parts, demulsifier 0.05-0.2 parts, and defoaming agent 0.01-0.2 parts. The modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester to the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 3-5:1-2:1-2:1.

[0008] Preferably, the ester group-containing hydrocarbon polymeric fluid is selected from at least one of VBS5-150, VBS5-180, VBS5-188, VISCOBASE11-570, VISCOBASE11-574, and VISCOBASE11-572.

[0009] Preferably, the aromatic ester base oil is selected from at least one of diisooctyl phthalate, diisodecyl phthalate and trimellitate ester.

[0010] Preferably, the cyclohexane diacid ester is selected from at least one of dimethyl(1S,2S)-cyclohexane-1,2-dicarboxylate, diethyl cyclohexane-1,4-dicarboxylate, di-isononyl-cyclohexane-1,2-dicarboxylate, and di-iso-octyl-cyclohexane-1,2-dicarboxylate.

[0011] Preferably, the polyol ester is selected from at least one of dipropylene glycol dibenzoate, dipentaerythritol ester, and glycerol triacetate.

[0012] Preferably, the antioxidant is selected from at least one of phenolic antioxidant, amine antioxidant, phosphite antioxidant, or high-molecular phenol-amine composite antioxidant.

[0013] Preferably, the extreme pressure anti-wear agent is selected from at least one of sulfide phosphonate, phosphate ester type extreme pressure anti-wear agent, phosphate type extreme pressure anti-wear agent, and amine phosphate type extreme pressure anti-wear agent.

[0014] Preferably, the corrosion inhibitor is selected from at least one of benzotriazole, methyl benzotriazole or derivatives thereof.

[0015] Preferably, the rust inhibitor is selected from one or more of dodecenyl succinic acid, sodium sebacate, barium neutral dinonylnaphthalene sulfonate and benzotriazole.

[0016] Preferably, the demulsifier is an oil-soluble non-ionic surfactant; the defoaming agent is at least one of a silicone defoaming agent, a non-silicone defoaming agent.

[0017] Preferably, the poly-alpha olefin is at least one of PAO2, PAO2.5, PAO3.5, PAO4, PAO5, PAO6, PAO7, PAO8, PAO9 and PAO10.

[0018] Preferably, the preparation method of the shaddock peel essential oil is as follows: shredded shaddock peel is heated with distilled water, water vapor carries volatile oil into a condenser for cooling, after separation of the oil-water mixture, water is removed to obtain the essential oil; wherein, the material-liquid ratio is 1:2~1:4, the heating temperature is 150 DEG C, the distillation time is 3~4h, and the NaCl salting-out is 1.5%.

[0019] In the second aspect, the application provides a preparation method of a compatible long-life low-loss food-grade screw air compressor oil, comprising the following steps: (1) adding a hydrocarbon polymer fluid containing an ester group functional group, an aromatic ester base oil, a modified polyol ester, a cyclohexane diacid ester, a poly-alpha olefin, shaddock peel essential oil and propyl gallate into a blending kettle, and heating and stirring uniformly; (2) adding an antioxidant, an extreme pressure anti-wear agent, a corrosion inhibitor, a rust inhibitor, a demulsifier and a defoaming agent into the blending kettle, and mixing uniformly; (3) after blending is completed, filtering with a filter bag with a filter diameter of 2~3 mu m, to obtain the compatible long-life low-loss food-grade screw air compressor oil.

[0020] In summary, the application has the following beneficial effects: 1. The polyol esters in this invention possess excellent antioxidant properties, maintaining the chemical stability of the oil under the high-temperature operating environment of the compressor, significantly reducing the risk of aging and acid value increase in air compressor oil. As a polar ester matrix, the polyol esters can form a homogeneous mixture with other cyclohexane diesters, exhibiting good compatibility; they can provide a solvent environment for the natural antioxidants grapefruit peel oil and propyl gallate, facilitating their uniform dispersion. Both polyol esters and cyclohexane diesters are ester compounds with similar polarities, enabling the formation of a homogeneous single-phase system, avoiding phase separation or precipitation. The modified polyol esters are prepared by adding diphenylamine, naphthylamine, and phenolic esters to the polyol esters, exhibiting good antioxidant effects in the system and inhibiting the oxidative decomposition of the oil under high-temperature operating conditions. Combined with the extreme pressure anti-wear agent and rust inhibitor selected in this invention, the oil possesses excellent extreme pressure anti-wear properties while exhibiting low corrosivity and excellent rust prevention capabilities. It can achieve advantages such as high-temperature oxidation resistance, low coking, low volatility, and excellent extreme pressure anti-wear and anti-corrosion, thereby improving the operational reliability of the compressor and extending the service life of the oil. Polyalphaolefins, with their low-temperature fluidity, high-temperature stability, oxidation and hydrolysis resistance, excellent rust and wear prevention, and good material compatibility, can significantly improve the reliability, efficiency and service life of air compressors.

[0021] 2. The cyclohexane diester in this invention is a branched diester, providing a high viscosity index (VI≈180-216) and good low-temperature fluidity, as well as excellent antioxidant properties. Similar to the ester bond structure of polyol esters, it exhibits strong miscibility and can be used as a viscosity index improver to enhance the viscosity-temperature characteristics of oils over a wide temperature range. The ester structure also helps to fix the volatile components in grapefruit peel essential oil, reducing their evaporation loss at high temperatures.

[0022] 3. The main components of the grapefruit peel essential oil in this invention are limonene, geraniol, β-caryophyllene, etc., which are natural antioxidants capable of capturing free radicals and providing certain friction-reducing and anti-wear effects. Some components possess surface activity, which can improve the lubrication uniformity of the oil film. The antioxidant activity in the essential oil forms a synergistic antioxidant effect with propyl gallate, and the two together inhibit the thermal oxidation of the oil. Furthermore, the polar components of the essential oil are easily soluble in the ester matrix, avoiding phase separation. Propyl gallate is a potent oil-soluble antioxidant that can inhibit the oxidative decomposition of oils at high temperatures, forming a double protection with the natural antioxidants in grapefruit peel essential oil, thereby improving the overall antioxidant index. It exists stably in the ester matrix without affecting viscosity characteristics and can reduce the degradation rate of the essential oil at high temperatures.

[0023] 4、The natural phenolic / terpenoid radical scavenging ability of the grapefruit peel essential oil and the phenolic acyl ester antioxidant mechanism of propyl gallate, both of which work in different temperature ranges, significantly improve the oxidative stability of the oil product. The terpenoids (such as limonene) in the grapefruit peel essential oil form a thin lubricating film on the metal surface, reducing the friction coefficient; the polyol ester and cyclohexane dibasic acid ester as the ester matrix provide high load bearing capacity. The combination of the two can achieve a balance of low friction and high load. Although propyl gallate is mainly an antioxidant, its phenolic hydroxyl group can form a thin protective layer in the high-pressure contact area, further inhibiting wear. The four additives are all esters or oil-soluble components, and can form a stable single-phase system in food-grade polyol ester base oil. The synergistic effect of the additives is: cyclohexane dibasic acid ester improves the viscosity index and thermal stability, grapefruit peel essential oil provides natural antioxidant and friction reduction, and propyl gallate enhances antioxidant protection. The combined action of the three makes the compressor oil maintain low viscosity decay, low sludge generation and long oil change cycle under high temperature and high load.

[0024] 5、The compatible long-life low-loss food-grade screw air compressor oil prepared in the present application uses modified polyol ester, cyclohexane dibasic acid ester, grapefruit peel essential oil and propyl gallate, which can significantly improve the high-temperature oxidation resistance, low-temperature fluidity, wear resistance and corrosion resistance of the screw air compressor oil under the premise of maintaining food-grade safety, prolong the service life of the oil, reduce oil consumption and operating costs, and realize the functions of long life, low loss and compatibility.

[0025] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the protection scope of the present application. DETAILED DESCRIPTION

[0026] The present application will be further described in detail below in combination with examples, and it should be particularly noted that: in the following examples, the specific conditions are not specified, and the conventional conditions or the conditions recommended by the manufacturer are used, and the raw materials used in the following examples can be obtained from ordinary market sales unless otherwise specified. EXAMPLE Example 1

[0027] A compatible long-life low-loss food-grade screw air compressor oil, comprising the following raw material components by weight: ester group-containing hydrocarbon polymeric fluid 7 parts, aromatic ester base oil 6 parts, modified polyol ester 2 parts, cyclohexane diacid ester 3 parts, polyalphaolefin 2 parts, natal oil 2 parts, propyl gallate 1 part, antioxidant 3 parts, extreme pressure anti-wear agent 0.5 parts, corrosion inhibitor 0.05 parts, rust inhibitor 0.05 parts, demulsifier 0.05 parts, and defoaming agent 0.01 parts; the modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 3:1:1:1.

[0028] The cyclohexane diacid ester is selected from dimethyl (1S, 2S)-cyclohexane-1, 2-dicarboxylic acid ester; the polyalphaolefin is selected from PAO2; the preparation method of the natal oil is: shredded natal peel is heated with distilled water, the water vapor carries the volatile oil into the condenser to cool, the oil-water mixture is separated, and the moisture is removed to obtain the essential oil; wherein, the material liquid ratio is 1:2, the heating temperature is 150 DEG C, the distillation time is 3h, and the NaCl salting-out is 1.5%.

[0029] The ester group-containing hydrocarbon polymeric fluid is selected from VBS5-150; the aromatic ester base oil is selected from diisooctyl phthalate; the polyol ester is selected from dipropylene glycol dibenzoate; the antioxidant is selected from the dialkyl phenol in the phenolic antioxidant; the extreme pressure anti-wear agent is selected from thio phosphonate; the corrosion inhibitor is selected from benzotriazole; the rust inhibitor is selected from dodecenyl succinic acid; the demulsifier is an oil-soluble nonionic surfactant; and the defoaming agent is an organic silicon defoaming agent.

[0030] A preparation method of a compatible long-life low-loss food-grade screw air compressor oil, comprising the following steps: (1) The ester group-containing hydrocarbon polymeric fluid, aromatic ester base oil, modified polyol ester, cyclohexane diacid ester, polyalphaolefin, natal oil and propyl gallate are added into a blending kettle and heated and stirred uniformly; (2) The antioxidant, extreme pressure anti-wear agent, corrosion inhibitor, rust inhibitor, demulsifier and defoaming agent are added into the blending kettle and mixed uniformly; (3) After blending is completed, a filter bag with a filter diameter of 2μm is used for filtration, and the compatible long-life low-loss food-grade screw air compressor oil is obtained. Example 2

[0031] A compatible long-life low-loss food-grade screw air compressor oil, comprising the following raw material components by weight: ester group-containing hydrocarbon polymeric fluid 8 parts, aromatic ester base oil 7 parts, modified polyol ester 3 parts, cyclohexane diacid ester 4 parts, polyalphaolefin 3 parts, natal oil 3 parts, propyl gallate 2 parts, antioxidant 4 parts, extreme pressure anti-wear agent 1 part, corrosion inhibitor 0.08 parts, rust inhibitor 0.08 parts, demulsifier 0.08 parts, and defoaming agent 0.05 parts; the modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 3:2:1:1.

[0032] The cyclohexane diacid ester is selected from dimethyl (1S, 2S)-cyclohexane-1, 2-dicarboxylic acid ester; the polyalphaolefin is selected from PAO2; the preparation method of the natal oil is: shredded natal peel is heated with distilled water, the water vapor carries the volatile oil into the condenser to cool, the oil-water mixture is separated, and the moisture is removed to obtain the essential oil; wherein, the material liquid ratio is 1:2, the heating temperature is 150 DEG C, the distillation time is 3h, and the NaCl salting-out is 1.5%.

[0033] The ester group-containing hydrocarbon polymeric fluid is selected from VBS5-150; the aromatic ester base oil is selected from diisooctyl phthalate; the polyol ester is selected from dipropylene glycol dibenzoate; the antioxidant is selected from a phenolic antioxidant with a molecular weight of 1500; the extreme pressure anti-wear agent is selected from a thio phosphonate; the corrosion inhibitor is selected from benzotriazole; the rust inhibitor is selected from dodecenyl succinic acid; the demulsifier is an oil-soluble non-ionic surfactant; and the defoaming agent is an organic silicon defoaming agent.

[0034] A preparation method of a compatible long-life low-loss food-grade screw air compressor oil, comprising the following steps: (1) The ester group-containing hydrocarbon polymeric fluid, aromatic ester base oil, modified polyol ester, cyclohexane diacid ester, polyalphaolefin, natal oil and propyl gallate are added into a blending kettle and heated and stirred uniformly; (2) The antioxidant, extreme pressure anti-wear agent, corrosion inhibitor, rust inhibitor, demulsifier and defoaming agent are added into the blending kettle and mixed uniformly; (3) After blending, the compatible long-life low-loss food-grade screw air compressor oil is obtained by filtering through a filter bag with a diameter of 2 μm. Example 3

[0035] A compatible long-life low-loss food-grade screw air compressor oil, comprising the following raw material components by weight: ester group-containing hydrocarbon polymeric fluid 9 parts, aromatic ester base oil 9 parts, modified polyol ester 4 parts, cyclohexane diacid ester 5 parts, poly-alpha olefin 3 parts, shaddock peel essential oil 3 parts, propyl gallate 2 parts, antioxidant 5 parts, extreme pressure anti-wear agent 1.2 parts, corrosion inhibitor 0.1 part, rust inhibitor 0.1 part, demulsifier 0.1 part, and defoaming agent 0.08 part; the modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 4:1:1:1.

[0036] The cyclohexane diacid ester is selected from dimethyl (1S, 2S)-cyclohexane-1, 2-dicarboxylic acid ester; the poly-alpha olefin is selected from PAO2; the shaddock peel essential oil is prepared by heating the shredded shaddock peel with distilled water, carrying the volatile oil into the condenser by water vapor, removing the water to obtain the essential oil after separating the oil-water mixture; wherein, the material-liquid ratio is 1:2, the heating temperature is 150℃, the distillation time is 3h, and the NaCl salting-out is 1.5%.

[0037] The ester group-containing hydrocarbon polymeric fluid is selected from VBS5-150; the aromatic ester base oil is selected from diisooctyl phthalate; the polyol ester is selected from dipropylene glycol dibenzoate; the antioxidant is selected from the dialkyl phenol in the phenolic antioxidant; the extreme pressure anti-wear agent is selected from thio phosphonate; the corrosion inhibitor is selected from benzotriazole; the rust inhibitor is selected from dodecenyl succinic acid; the demulsifier is an oil-soluble non-ionic surfactant; and the defoaming agent is an organic silicon defoaming agent.

[0038] A preparation method of a compatible long-life low-loss food-grade screw air compressor oil, comprising the following steps: (1) adding the ester group-containing hydrocarbon polymeric fluid, aromatic ester base oil, modified polyol ester, cyclohexane diacid ester, poly-alpha olefin, shaddock peel essential oil and propyl gallate into a blending kettle, and heating and stirring uniformly; (2) adding the antioxidant, extreme pressure anti-wear agent, corrosion inhibitor, rust inhibitor, demulsifier and defoaming agent into the blending kettle, and mixing uniformly; (3) after the blending is completed, filtering through a filter bag with a filter diameter of 2μm to obtain the compatible long-life low-loss food-grade screw air compressor oil. Example 4

[0039] A compatible long-life low-loss food-grade screw air compressor oil, comprising the following raw material components by weight: ester group-containing hydrocarbon polymeric fluid 10 parts, aromatic ester base oil 9 parts, modified polyol ester 5 parts, cyclohexane diacid ester 5 parts, polyalphaolefin 4 parts, natal oil 3 parts, propyl gallate 1 part, antioxidant 3 parts, extreme pressure anti-wear agent 1.5 parts, corrosion inhibitor 0.12 parts, rust inhibitor 0.05 parts, demulsifier 0.06 parts, and defoaming agent 0.06 parts; the modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 3:2:2:1.

[0040] The cyclohexane diacid ester is selected from dimethyl (1S, 2S)-cyclohexane-1, 2-dicarboxylic acid ester; the polyalphaolefin is selected from PAO2; the preparation method of the natal oil is: shredded natal peel is heated with distilled water, the water vapor carries the volatile oil into the condenser to cool, the oil-water mixture is separated, and the moisture is removed to obtain the essential oil; wherein, the material liquid ratio is 1:2, the heating temperature is 150 DEG C, the distillation time is 3h, and the NaCl salting-out is 1.5%.

[0041] The ester group-containing hydrocarbon polymeric fluid is selected from VBS5-150; the aromatic ester base oil is selected from diisooctyl phthalate; the polyol ester is selected from dipropylene glycol dibenzoate; the antioxidant is selected from a phenolic antioxidant with a molecular weight of 1500; the extreme pressure anti-wear agent is selected from a thio phosphonate; the corrosion inhibitor is selected from benzotriazole; the rust inhibitor is selected from dodecenyl succinic acid; the demulsifier is an oil-soluble non-ionic surfactant; and the defoaming agent is an organic silicon defoaming agent.

[0042] A preparation method of a compatible long-life low-loss food-grade screw air compressor oil, comprising the following steps: (1) The ester group-containing hydrocarbon polymeric fluid, aromatic ester base oil, modified polyol ester, cyclohexane diacid ester, polyalphaolefin, natal oil and propyl gallate are added into a blending kettle and heated and stirred uniformly; (2) The antioxidant, extreme pressure anti-wear agent, corrosion inhibitor, rust inhibitor, demulsifier and defoaming agent are added into the blending kettle and mixed uniformly; (3) After blending, the compatible long-life low-loss food-grade screw air compressor oil is obtained by filtering through a filter bag with a diameter of 2 μm. Example 5

[0043] A compatible long-life low-loss food-grade screw air compressor oil, comprising the following raw material components by weight: ester group-containing hydrocarbon polymeric fluid 12 parts, aromatic ester base oil 10 parts, modified polyol ester 3 parts, cyclohexane diacid ester 3 parts, poly-alpha olefin 4 parts, natal oil 3 parts, propyl gallate 2 parts, antioxidant 3 parts, extreme pressure anti-wear agent 1.2 parts, corrosion inhibitor 0.1 parts, rust inhibitor 0.3 parts, demulsifier 0.08 parts, and defoaming agent 0.12 parts; the modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 3:1:2:1.

[0044] The cyclohexane diacid ester is selected from dimethyl (1S, 2S)-cyclohexane-1, 2-dicarboxylic acid ester; the poly-alpha olefin is selected from PAO2; the preparation method of the natal oil is: shredded natal peel is heated with distilled water, the water vapor carries the volatile oil into the condenser to cool, the oil-water mixture is separated, and the moisture is removed to obtain the essential oil; wherein, the material liquid ratio is 1:2, the heating temperature is 150 DEG C, the distillation time is 3h, and the NaCl salting-out is 1.5%.

[0045] The ester group-containing hydrocarbon polymeric fluid is selected from VBS5-150; the aromatic ester base oil is selected from diisooctyl phthalate; the polyol ester is selected from dipropylene glycol dibenzoate; the antioxidant is selected from the dialkyl phenol in the phenolic antioxidant; the extreme pressure anti-wear agent is selected from thio phosphonate; the corrosion inhibitor is selected from benzotriazole; the rust inhibitor is selected from dodecenyl succinic acid; the demulsifier is an oil-soluble non-ionic surfactant; and the defoaming agent is an organic silicon defoaming agent.

[0046] A preparation method of a compatible long-life low-loss food-grade screw air compressor oil, comprising the following steps: (1) The ester group-containing hydrocarbon polymeric fluid, aromatic ester base oil, modified polyol ester, cyclohexane diacid ester, poly-alpha olefin, natal oil and propyl gallate are added into a blending kettle and heated and stirred uniformly; (2) The antioxidant, extreme pressure anti-wear agent, corrosion inhibitor, rust inhibitor, demulsifier and defoaming agent are added into the blending kettle and mixed uniformly; (3) After blending is completed, the compatible long-life low-loss food-grade screw air compressor oil is obtained by filtering with a filter bag with a filter diameter of 3μm. Example 6

[0047] A compatible long-life low-loss food-grade screw air compressor oil, comprising the following raw material components by weight: ester group-containing hydrocarbon polymeric fluid 16 parts, aromatic ester base oil 12 parts, modified polyol ester 4 parts, cyclohexane dibasic acid ester 5 parts, polyalphaolefin 2 parts, shaddock peel essential oil 3 parts, propyl gallate 2 parts, antioxidant 4 parts, extreme pressure anti-wear agent 2 parts, corrosion inhibitor 0.15 parts, rust inhibitor 0.3 parts, demulsifier 0.1 parts, defoaming agent 0.12 parts; the modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 5:1:1:1.

[0048] The cyclohexane dibasic acid ester is selected from dimethyl (1S, 2S)-cyclohexane-1, 2-dicarboxylic acid ester; the polyalphaolefin is selected from PAO2; the preparation method of the shaddock peel essential oil is: the chopped shaddock peel is heated with distilled water, the water vapor carries the volatile oil into the condenser for cooling, the oil-water mixture is separated, and the moisture is removed to obtain the essential oil; wherein, the material liquid ratio is 1:2, the heating temperature is 150 DEG C, the distillation time is 3h, and the NaCl salting-out is 1.5%.

[0049] The ester group-containing hydrocarbon polymeric fluid is selected from VBS5-150; the aromatic ester base oil is selected from diisooctyl phthalate; the polyol ester is selected from dipropylene glycol dibenzoate; the antioxidant is selected from the dialkyl phenol in the phenolic antioxidant; the extreme pressure anti-wear agent is selected from thio phosphonate; the corrosion inhibitor is selected from benzotriazole; the rust inhibitor is selected from dodecenyl succinic acid; the demulsifier is an oil-soluble nonionic surfactant; and the defoaming agent is an organic silicon defoaming agent.

[0050] A preparation method of a compatible long-life low-loss food-grade screw air compressor oil, comprising the following steps: (1) the ester group-containing hydrocarbon polymeric fluid, aromatic ester base oil, modified polyol ester, cyclohexane dibasic acid ester, polyalphaolefin, shaddock peel essential oil and propyl gallate are added into a blending kettle and heated and stirred uniformly; (2) the antioxidant, extreme pressure anti-wear agent, corrosion inhibitor, rust inhibitor, demulsifier and defoaming agent are added into the blending kettle and mixed uniformly; (3) after the blending is completed, the compatible long-life low-loss food-grade screw air compressor oil is obtained by filtering with a filter bag with a filter diameter of 2 μm. Example 7

[0051] A compatible long-life low-loss food-grade screw air compressor oil, comprising the following raw material components by weight: ester group-containing hydrocarbon polymeric fluid 18 parts, aromatic ester base oil 10 parts, modified polyol ester 8 parts, cyclohexane dibasic acid ester 7 parts, poly-alpha olefin 3 parts, natal grapefruit essential oil 3 parts, propyl gallate 2 parts, antioxidant 4 parts, extreme pressure anti-wear agent 2.5 parts, corrosion inhibitor 0.18 parts, rust inhibitor 0.4 parts, demulsifier 0.15 parts, and defoaming agent 0.15 parts; the modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 5:1:2:1.

[0052] The cyclohexane dibasic acid ester is selected from dimethyl (1S, 2S)-cyclohexane-1, 2-dicarboxylic acid ester; the poly-alpha olefin is selected from PAO2; the preparation method of the natal grapefruit essential oil is: shredded natal grapefruit is heated with distilled water, the water vapor carries the volatile oil into the condenser for cooling, the oil-water mixture is separated, and the moisture is removed to obtain the essential oil; wherein, the material liquid ratio is 1:2, the heating temperature is 150 DEG C, the distillation time is 3h, and the NaCl salting-out is 1.5%.

[0053] The ester group-containing hydrocarbon polymeric fluid is selected from VBS5-150; the aromatic ester base oil is selected from diisooctyl phthalate; the polyol ester is selected from dipropylene glycol dibenzoate; the antioxidant is selected from the dialkyl phenol in the phenolic antioxidant; the extreme pressure anti-wear agent is selected from thio phosphonate; the corrosion inhibitor is selected from benzotriazole; the rust inhibitor is selected from dodecenyl succinic acid; the demulsifier is an oil-soluble non-ionic surfactant; and the defoaming agent is an organic silicon defoaming agent.

[0054] A preparation method of a compatible long-life low-loss food-grade screw air compressor oil, comprising the following steps: (1) the ester group-containing hydrocarbon polymeric fluid, aromatic ester base oil, modified polyol ester, cyclohexane dibasic acid ester, poly-alpha olefin, natal grapefruit essential oil and propyl gallate are added into a blending kettle and heated and stirred uniformly; (2) the antioxidant, extreme pressure anti-wear agent, corrosion inhibitor, rust inhibitor, demulsifier and defoaming agent are added into the blending kettle and mixed uniformly; (3) after the blending is completed, the compatible long-life low-loss food-grade screw air compressor oil is obtained by filtering with a filter bag with a filter diameter of 3μm. Example 8

[0055] A compatible long-life low-loss food-grade screw air compressor oil, comprising the following raw material components in parts by weight: ester group-containing hydrocarbon polymeric fluid 21 parts, aromatic ester base oil 18 parts, modified polyol ester 9 parts, cyclohexane dibasic acid ester 8 parts, poly-alpha olefin 5 parts, shaddock peel essential oil 5 parts, propyl gallate 3 parts, antioxidant 6 parts, extreme pressure anti-wear agent 3 parts, corrosion inhibitor 0.2 parts, rust inhibitor 0.5 parts, demulsifier 0.2 parts, and defoaming agent 0.2 parts; the modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 5:2:2:1.

[0056] The cyclohexane dibasic acid ester is selected from dimethyl (1S, 2S)-cyclohexane-1, 2-dicarboxylic acid ester; the poly-alpha olefin is selected from PAO2; the preparation method of the shaddock peel essential oil is: heating the chopped shaddock peel with distilled water, the water vapor carrying the volatile oil into the condenser for cooling, separating the oil-water mixture and removing the water to obtain the essential oil; wherein, the material liquid ratio is 1:2, the heating temperature is 150℃, the distillation time is 3h, and the NaCl salting-out is 1.5%.

[0057] The ester group-containing hydrocarbon polymeric fluid is selected from VBS5-150; the aromatic ester base oil is selected from diisooctyl phthalate; the polyol ester is selected from dipropylene glycol dibenzoate; the antioxidant is selected from dialkyl phenol in phenolic antioxidants; the extreme pressure anti-wear agent is selected from thio phosphonate; the corrosion inhibitor is selected from benzotriazole; the rust inhibitor is selected from dodecenyl succinic acid; the demulsifier is an oil-soluble non-ionic surfactant; and the defoaming agent is an organic silicon defoaming agent.

[0058] A preparation method of a compatible long-life low-loss food-grade screw air compressor oil, comprising the following steps: (1) adding the ester group-containing hydrocarbon polymeric fluid, the aromatic ester base oil, the modified polyol ester, the cyclohexane dibasic acid ester, the poly-alpha olefin, the shaddock peel essential oil and the propyl gallate into a blending kettle, and heating and stirring uniformly; (2) adding the antioxidant, the extreme pressure anti-wear agent, the corrosion inhibitor, the rust inhibitor, the demulsifier and the defoaming agent into the blending kettle, and mixing uniformly; (3) after the blending is completed, filtering with a filter bag with a filter diameter of 3μm to obtain the compatible long-life low-loss food-grade screw air compressor oil.

[0059] Comparative Example 1 The same as Example 1, except that the cyclohexane dibasic acid ester is not added.

[0060] Comparative Example 2 The same as Example 1, except that the modified polyol ester is not added.

[0061] Comparative Example 3 The same as example 1, except that the naringin essential oil is not added.

[0062] Comparative example 4 The same as example 1, except that the propyl gallate is not added.

[0063] Comparative example 5 The same as example 1, except that the modified polyol ester is replaced by polyol ester.

[0064] Test method: 1. Viscosity index: the kinematic viscosity of the lubricating oil is tested according to the standard of GB / T 265, and the corresponding viscosity index is calculated according to the standard of GB / T 1995.

[0065] 2. Pour point: the pour point of the lubricating oil is tested according to the standard of GB / T 3535-2006.

[0066] 3. Wear scar diameter: the wear scar diameter of the lubricating oil is tested according to the standard of GB / T 212-2008.

[0067] 4. Rotating bomb: the oxidation characteristics of the lubricating oil are tested according to the standard of GB / T 12581.

[0068] Table 1 Performance test results Viscosity index Pour point / °C Abrasion diameter (1200 rpm, 75°C, 395 N, 60 min) / mm Rotary oxygen bomb (150°C) / min Example 1 152 -55 0.40 2250 Example 2 148 -54 0.41 2240 Example 3 145 -55 0.42 2230 Example 4 146 -52 0.41 2210 Example 5 151 -53 0.40 2220 Example 6 144 -55 0.44 2230 Example 7 147 -54 0.42 2240 Example 8 149 -52 0.41 2210 Comparative Example 1 124 -32 0.48 1250 Comparative Example 2 121 -36 0.49 1220 Comparative Example 3 132 -42 0.45 1280 Comparative Example 4 122 -38 0.47 1230 Comparative Example 5 124 -40 0.48 1250 As shown in Table 1, the compatible long-life low-loss food-grade screw air compressor oil prepared in the example has good viscosity, and also has good antioxidant performance and wear resistance, which shows that the four components of modified polyol ester, cyclohexane diacid ester, naringin essential oil and propyl gallate are used in combination, which can significantly improve the high-temperature oxidation resistance, low-temperature flowability, wear resistance and corrosion resistance of the screw air compressor oil under the premise of maintaining food-grade safety.

[0069] The above is only an exemplary specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A compatible long life low loss food grade screw air compressor oil characterized in that, The raw material components include the following by weight: 7-21 parts of a carbon-hydrogen polymer fluid containing ester group functional groups, 6-18 parts of an aromatic ester base oil, 2-9 parts of a modified polyol ester, 3-8 parts of a cyclohexane dibasic acid ester, 2-5 parts of a poly-alpha olefin, 2-5 parts of a naring peel essential oil, 1-3 parts of propyl gallate, 3-6 parts of an antioxidant, 0.5-3 parts of an extreme pressure anti-wear agent, 0.05-0.2 parts of a corrosion inhibitor, 0.05-0.5 parts of a rust inhibitor, 0.05-0.2 parts of a demulsifier, and 0.01-0.2 parts of an antifoaming agent. The modified polyol ester is prepared by adding diphenylamine, naphthylamine and phenolic ester into the polyol ester, and the mass ratio of the polyol ester, diphenylamine, naphthylamine and phenolic ester is 3-5:1-2:1-2:

1.

2. The compatible long life low loss food grade screw compressor oil of claim 1, wherein, The carbon-hydrogen polymer fluid containing ester group functional groups is selected from at least one of VBS5-150, VBS5-180, VBS5-188, VISCOBASE11-570, VISCOBASE11-574 and VISCOBASE11-572.

3. The compatible long life low loss food grade screw compressor oil of claim 1, wherein, The aromatic ester base oil is selected from at least one of diisooctyl phthalate, diisodecyl phthalate and trimellitate.

4. The long life, low loss, food grade, compatible screw compressor oil of claim 1, wherein, The polyol ester is selected from at least one of dipropylene glycol dibenzoate, dipentaerythritol ester and glycerol triacetate.

5. The compatible long life low loss food grade screw compressor oil of claim 1, wherein, The antioxidant is selected from at least one of a phenolic antioxidant, an amine antioxidant, a phosphite ester, a phosphite salt antioxidant or a high-molecular phenol and amine composite antioxidant.

6. The long life, low loss, food grade, compatible, screw compressor oil of claim 1, wherein, The extreme pressure anti-wear agent is selected from at least one of a phosphonothioate, a phosphate ester type extreme pressure anti-wear agent, a phosphate salt type extreme pressure anti-wear agent and an amine phosphate type extreme pressure anti-wear agent.

7. The long life, low loss, food grade, compatible, screw compressor oil of claim 1, wherein, The corrosion inhibitor is selected from at least one of benzotriazole, methyl benzotriazole or a derivative thereof.

8. The long life, low loss, food grade, compatible, screw compressor oil of claim 1, wherein, The rust inhibitor is selected from one or more of dodecenyl succinic acid, sodium sebacate, neutral dinonyl naphthalene barium sulfonate and benzotriazole.

9. The long life, low loss, food grade, compatible, screw compressor oil of claim 1, wherein, The demulsifier is an oil-soluble non-ionic surfactant, and the antifoaming agent is at least one of a silicone antifoaming agent and a non-silicone antifoaming agent.

10. The process for the preparation of a compatible long life low loss food grade screw compressor oil as claimed in any one of claims 1 to 9, wherein, The method comprises the following steps: (1) adding the carbon-hydrogen polymer fluid containing ester group functional groups, the aromatic ester base oil, the modified polyol ester, the cyclohexane dibasic acid ester, the poly-alpha olefin, the naring peel essential oil and the propyl gallate into a blending kettle, and heating and stirring to be uniform; (2) adding the antioxidant, the extreme pressure anti-wear agent, the corrosion inhibitor, the rust inhibitor, the demulsifier and the antifoaming agent into the blending kettle, and mixing to be uniform; (3) after the blending is completed, filtering through a filter bag with a filter diameter of 2-3 μm to obtain the compatible long-life low-loss food-grade screw air compressor oil.