CN112391203A

CN112391203A - Asphaltene dispersant, oil product and application thereof

Info

Publication number: CN112391203A
Application number: CN202011344173.7A
Authority: CN
Inventors: 陈傲; 严斌; 熊靓
Original assignee: SHENZHEN GUANGCHANGDA ENVIRONMENTAL SCIENCES CO LTD; Shenzhen Guangchangda Petroleum Additive Co ltd; Guangchangda New Material Technology Service Shenzhen Co ltd
Current assignee: SHENZHEN GUANGCHANGDA ENVIRONMENTAL SCIENCES CO LTD; Shenzhen Guangchangda Petroleum Additive Co ltd; Guangchangda New Material Technology Service Shenzhen Co ltd
Priority date: 2020-11-26
Filing date: 2020-11-26
Publication date: 2021-02-23
Anticipated expiration: 2040-11-26
Also published as: CN112391203B

Abstract

The invention relates to an asphaltene dispersant, which comprises aromatic polyester polyol, block polyoxyethylene polyoxypropylene ether amine, a surfactant, an aromatic hydrocarbon solvent and the like. The aromatic polyester polyol contains a large number of benzene rings and polar groups, and can destroy the hydrogen bond function among asphaltene molecules; the long chain of the block polyoxyethylene polyoxypropylene ether amine can form a stable space structure, the mutual repulsion among asphaltene molecules is enhanced under the combined action of the block polyoxyethylene polyoxypropylene ether amine and aromatic polyester polyol, and the dispersibility and the aggregation resistance are effectively improved; in addition, the block polyoxyethylene polyoxypropylene ether amine has appropriate lipophilic and hydrophilic properties, and the dispersing effect is better; the aromatic solvent and the surfactant with better lipophilicity are selected to act together with the aromatic polyester polyol and the block polyoxyethylene polyoxypropylene ether amine, so that the method is beneficial to the dissociation of asphaltene macromolecules, the dispersion of asphaltene, the delay of the initial flocculation point of the asphaltene, the enhancement of the stability of the asphaltene in a crude oil solution and the prevention of aggregation and deposition.

Description

Asphaltene dispersant, oil product and application thereof

Technical Field

The invention relates to the field of crude oil treatment, and particularly relates to an asphaltene dispersant, an oil product and application thereof.

Background

Substances that are insoluble in n-heptane but soluble in toluene in petroleum are generally referred to as asphaltenes. Asphaltenes are the heaviest, most polar components of the heavy oil components and are complex structures having alkyl branches and polycyclic aromatic or naphthenic aromatic nuclei containing significant amounts of oxygen, nitrogen, and sulfur heteroatoms. Many forces exist between asphaltene molecules, such as pi-pi interactions between aromatic rings, lewis acid-base interactions between heteroatoms, and hydrogen bonding, and the like, and the existence of these forces gives asphaltene molecules a strong tendency to self-associate. The flocculation and deposition of the asphaltenes have negative effects on the production, transportation, storage and the like of oil products, particularly heavy oil.

The traditional method for solving the problem of asphaltene deposition mainly comprises two methods: one is to dissolve the asphaltene by using an aromatic hydrocarbon solvent, and the other is to disperse the asphaltene by adding an asphaltene dispersant. The method for dissolving the asphaltene by using the aromatic hydrocarbon solvent has the problems of large solvent consumption, high cost, short treatment effect maintaining time, frequent operation, environmental pollution and the like. The addition of the asphalt dispersant is a method for effectively treating asphaltene deposition, and the method has the advantages of cost saving and simple construction.

Conventional asphaltene dispersants generally fall into two categories: one is compounded by a conventional surfactant and a solvent; the other is an asphaltene dispersant obtained by chemically modifying a polar group. However, the asphaltene dispersant composed of conventional surfactant and solvent usually needs a large amount of the surfactant to achieve the effect of dispersing asphaltene, and needs to be subjected to demulsification and dehydration treatment; however, the asphaltene dispersant obtained by chemically modifying the polar group is usually adsorbed on the side chain of the asphaltene molecule, and is difficult to completely dissociate the asphaltene, and the dispersion effect is still not ideal.

Disclosure of Invention

In view of this, it is necessary to provide an asphaltene dispersant capable of improving the asphaltene dispersing effect.

The invention provides an asphaltene dispersant, which comprises the following components in percentage by mass:

in some of these embodiments, the aromatic polyester polyol has a molecular weight of 500 to 3000.

In some of these embodiments, the aromatic polyester polyol is selected from one or more of the group consisting of the phthalic anhydride polyester polyol PS-450, the phthalic anhydride polyester polyol PS-550, the phthalic anhydride polyester polyol PS-1000, and the phthalic anhydride polyester polyol PS-2000.

In some embodiments, the molar ratio of the oxyethyl group to the oxypropyl group in the block polyoxyethylene polyoxypropylene ether amine is (2-3): 1.

in some of the embodiments, the molecular weight of the block polyoxyethylene polyoxypropylene ether amine is 200-1200.

In some of these embodiments, the block polyoxyethylene polyoxypropylene ether amine is selected from one or more of polyetheramine ED600, polyetheramine ED900 and polyetheramine ED 1200.

In some of these embodiments, the surfactant is selected from one or more of sorbitan fatty acid esters, glyceryl monostearate, and glycol fatty acid esters.

In some of these embodiments, the asphaltene dispersant comprises the following components in mass percent:

the asphaltene dispersant comprises aromatic polyester polyol, block polyoxyethylene polyoxypropylene ether amine, a surfactant, an aromatic hydrocarbon solvent and the like. The aromatic polyester polyol contains a large number of aromatic rings and various polar groups, can generate interaction with asphaltene molecules, adheres to the asphaltene molecules and destroys hydrogen bond interaction and pi-pi interaction between the asphaltene molecules; the block polyoxyethylene polyoxypropylene ether amine forms a stable spatial structure through long-chain bridging, the mutual repulsion among asphaltene molecules is enhanced under the combined action of the block polyoxyethylene polyoxypropylene ether amine and aromatic polyester polyol, the dispersibility and the anti-aggregation capability are effectively improved, and the block polyoxyethylene polyoxypropylene ether amine has proper lipophilic and hydrophilic properties and is better in dispersing effect; the aromatic solvent and the surfactant with better lipophilicity are selected to act together with the aromatic polyester polyol and the block polyoxyethylene polyoxypropylene ether amine, so that the method is favorable for the dissociation of asphaltene macromolecules, delays the initial flocculation point of the asphaltene, enhances the stability of the asphaltene in the solution, ensures that the asphaltene in the crude oil is not easy to aggregate and deposit, and is particularly suitable for the asphaltene dispersion of the heavy crude oil.

Meanwhile, the components of the asphaltene dispersant are wide in source, and can be prepared by simply mixing the components, the preparation process is simple, the production flexibility is strong, and the using effect of the product is greatly improved compared with that of the traditional asphaltene dispersant.

The invention also provides an application of the asphaltene dispersant in crude oil processing.

The asphaltene dispersant can effectively disperse asphaltene molecules contained in crude oil, prevents the aggregation and association of asphaltene macromolecules, can be used in the processes of processing, transporting and storing of the crude oil, and is beneficial to avoiding or reducing the negative influence caused by asphaltene deposition.

The invention also provides an oil product which contains the asphaltene dispersant.

The oil product is added with the asphaltene dispersant comprising the components of aromatic polyester polyol, block polyoxyethylene polyoxypropylene ether amine, surfactant, aromatic hydrocarbon solvent and the like, so that the asphaltene dispersant in the oil product has good dispersibility, delayed initial flocculation point and difficult aggregation and deposition.

Drawings

FIG. 1 is a graph showing the determination of initial asphaltene flocculation point for various toluene to crude oil mass ratios according to one embodiment of the present invention;

FIG. 2 is a graph of the mass ratio of toluene to crude oil versus the measured initial asphaltene flocculation point for the present invention; the abscissa M (toluene)/M (crude oil) is the mass ratio of toluene to crude oil; the ordinate M (n-heptane)/M (crude oil) is the mass ratio of n-heptane to crude oil, indicating the initial flocculation point of asphaltenes.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

One embodiment of the invention provides an asphaltene dispersant, which comprises the following components in percentage by mass:

the asphaltene dispersant comprises aromatic polyester polyol, block polyoxyethylene polyoxypropylene ether amine, a surfactant and aromatic hydrocarbon solvent components. The aromatic polyester polyol contains a large number of aromatic rings and various polar groups, can generate interaction with asphaltene molecules, adheres to the asphaltene molecules, and destroys hydrogen bond interaction and pi-pi interaction between the asphaltene molecules. The block polyoxyethylene polyoxypropylene ether amine forms a stable spatial structure through long-chain bridging, the mutual repulsion among asphaltene molecules is enhanced under the combined action of the block polyoxyethylene polyoxypropylene ether amine and aromatic polyester polyol, the dispersibility and the anti-aggregation capability are effectively improved, and in addition, the block polyoxyethylene polyoxypropylene ether amine has proper lipophilic and hydrophilic properties and is better in dispersing effect. The aromatic solvent and the surfactant with better lipophilicity are selected to act together with the aromatic polyester polyol and the block polyoxyethylene polyoxypropylene ether amine, so that the method is beneficial to the dissociation of asphaltene macromolecules, delays the initial flocculation point of the asphaltene, enhances the stability of the asphaltene in the solution and ensures that the asphaltene is not easy to aggregate and deposit.

Meanwhile, the components of the asphaltene dispersant are wide in source, the asphaltene dispersant can be prepared by simply mixing the components, the preparation process is simple, the production flexibility is high, and the using effect of the product is greatly improved compared with that of the traditional asphaltene dispersant.

In some of these embodiments, the aromatic polyester polyol is selected from one or more of the group consisting of the phthalic anhydride polyester polyol PS-450, the phthalic anhydride polyester polyol PS-550, the phthalic anhydride polyester polyol PS-1000, and the phthalic anhydride polyester polyol PS-2000. The aromatic polyester polyol can achieve a good asphaltene dispersion effect in the asphaltene dispersant.

In some embodiments, the molar ratio of the oxyethyl group to the oxypropyl group in the block polyoxyethylene polyoxypropylene ether amine is (2-3): 1. preferably, the molar ratio of the oxyethyl group to the oxypropyl group in the block polyoxyethylene polyoxypropylene ether amine is 2.5: 1. specifically, the molar ratio of oxyethyl groups to oxypropyl groups is 2.5: the block polyoxyethylene polyoxypropylene ether amine of 1 has appropriate lipophilic and hydrophilic properties, and has good dispersing effect on asphaltene molecules.

In some of the embodiments, the molecular weight of the block polyoxyethylene polyoxypropylene ether amine is 200-1200. Within this molecular weight range, the block polyoxyethylene polyoxypropylene ether amine can form a stable steric structure, which contributes to the improvement of asphaltene dispersion effect.

In some of these embodiments, the surfactant is selected from one or more of sorbitan fatty acid esters, glyceryl monostearate, and glycol fatty acid esters. Preferably, the surfactant is a sorbitan fatty acid ester. The sorbitan fatty acid ester has good lipophilicity, can enable the asphaltene dispersant to quickly enter asphaltene sediments, and improves the effects of dissolving and dispersing the asphaltene. Specifically, the sorbitan fatty acid ester is selected from one or more of Span20, Span40, Span60, Span80 and Span 85. Among them, Span60 has good solubility in aromatic hydrocarbon solvents and better effect on asphaltene molecule dispersion due to proper lipophilicity and polarity.

In some of these embodiments, the aromatic hydrocarbon solvent is selected from one or more of mixed xylenes, mixed trimethylbenzenes, and mixed tetramethylbenzenes. Preferably, the aromatic hydrocarbon solvent is durene. The mixed tetramethylbenzene has higher flash point, good lipophilicity as a solvent, good compatibility with aromatic polyester polyol, block polyoxyethylene polyoxypropylene ether amine and a surfactant in the asphalt dispersant, and can damage pi-pi interaction among asphaltene molecules under synergistic action, thereby avoiding the aggregation and deposition of the asphaltene molecules and improving the asphaltene dispersion effect.

the asphaltene dispersant contains 35-40% of aromatic polyester polyol and 20-25% of block polyoxyethylene polyoxypropylene ether amine, has good asphaltene dispersion effect, and has low consumption of aromatic polyester polyol and block polyoxyethylene polyoxypropylene ether amine, thereby reducing production cost.

An embodiment of the present invention also provides a method for preparing any one of the above asphaltene dispersants. Further, the asphaltene dispersants can be prepared by mixing the components of any of the above asphaltene dispersants.

An embodiment of the invention also provides the use of any one of the asphaltene dispersants in crude oil processing.

The asphaltene dispersant can effectively avoid deposition of asphaltene molecules in crude oil, can be used in the processes of crude oil processing, transportation and storage, is particularly suitable for heavy oil, and is beneficial to avoiding negative effects caused by asphaltene deposition.

An embodiment of the present invention also provides an oil product containing any of the above asphaltene dispersants.

In some of the examples, the asphaltene dispersant is present in the oil in an amount of 200ppm to 400 ppm.

The action of the asphaltene dispersant of the present invention will be specifically described below by way of specific examples.

Example 1:

the asphaltene dispersant comprises the following components in percentage by mass:

example 2:

example 3:

example 4:

example 5:

example 6:

comparative example 1:

comparative example 2:

comparative example 3:

PS 200040% of phthalic anhydride polyester polyol;

polyether amine ED 900025%; and

mixed tetramethylbenzene 35 percent.

Comparative example 4:

comparative example 5:

comparative example 6:

asphaltene molecules bind to colloidal molecules in crude oil and exist as a colloidal solution, and when a precipitant, such as n-heptane, is added to the crude oil solution, the relatively stable colloidal system is broken down, resulting in flocculation and precipitation of asphaltenes in the crude oil. The initial flocculation point of asphaltenes in a crude oil system is generally obtained by adding a precipitant to the crude oil system and detecting the change of light transmittance of the crude oil system. The light transmittance of the crude oil system is comprehensively influenced by factors such as the dilution effect of a precipitator and the scattering effect of large asphaltene particles, and the light absorbance of toluene and n-heptane is smaller than that of asphaltene, so that the aggregation condition of the asphaltene in the crude oil system can be reflected through the change of the light transmittance of the system. Generally, the M (precipitant)/M (crude oil) value corresponding to the time at which the light transmittance value of a crude oil system begins to decrease is defined as the initial flocculation point of asphaltenes in the system. If the initial flocculation point of the asphaltene is a positive value, indicating that the oil sample is stable, a precipitator is required to precipitate the asphaltene; if the initial flocculation point of the asphaltene is negative, the oil sample is unstable, and the asphaltene deposition exists in the oil sample.

The initial flocculation point of asphaltenes in crude oil will be tested by spectrophotometry to evaluate the dispersing effect of asphaltene dispersants on asphaltenes.

Firstly, preparing a certain heavy crude oil with high asphaltene content into toluene solutions with different proportions, wherein the mass ratio of toluene to crude oil is 30:1, 40:1, 50:1 and 60:1 respectively. Then, a toluene/crude oil mixed solution with an actual crude oil content of 0.5g is taken, n-heptane with different qualities is added into each toluene/crude oil mixed solution, a spectrophotometer is used for testing the change condition of the light transmittance of the toluene/crude oil mixed solution along with the increase of the added n-heptane quantity, and the asphaltene initial flocculation point of the crude oil is measured.

As shown in fig. 1, which is a plot of the initial asphaltene flocculation point of crude oil at different toluene to crude oil mass ratios. As can be seen from FIG. 1, as the amount of n-heptane added increases, the transmittance of the toluene solution of each crude oil increases and then decreases, and the peak point on the line connecting the points is taken as the initial flocculation point of asphaltenes in the toluene solution of the crude oil. From FIG. 1, it can be found that as the mass ratio of toluene to crude oil increases, the amount of n-heptane reaching the initial flocculation point of asphaltene gradually increases, indicating that the initial flocculation point of asphaltene gradually increases.

Further, from the initial flocculation point of asphaltenes measured in FIG. 1, a standard curve is plotted for the toluene to crude oil mass ratio versus the initial flocculation point (see FIG. 2 in particular). The equation for fitting a standard curve of toluene to crude mass ratio (M (toluene)/M (crude)) to initial asphaltene flocculation point (M (n-heptane)/M (crude)) is: y is 0.43x-7.60, and the correlation coefficient is as follows: r²0.9968 where x represents the mass ratio of toluene to crude oil (M (toluene)/M (crude oil)), y represents the initial flocculation point of asphaltenes (M (n-heptane)/M (crude oil)), and R²0.9968 shows that the standard curve fitting formula has high reliability. From the above fit equation, it can be seen that when crude oil is diluted without toluene, i.e., x is 0, the initial flocculation point of asphaltenes in the crude oil is-7.60, indicating that the heavy crude oil is unstable and contains asphaltene deposits itself.

Examples 7 to 12:

the asphaltene dispersants of examples 1-6 were added to the crude oil at 60 ℃ in an amount of 300ppm to obtain the crude oils of examples 7-12.

Comparative examples 7 to 14:

and respectively adding the asphaltene dispersants of the comparative examples 1 to 6 into the crude oil at the temperature of 60 ℃, wherein the addition amount of the asphaltene dispersant is 300ppm, and obtaining the crude oil to be tested of the comparative examples 7 to 12. The crude oil to be tested of comparative example 13 was used as a blank crude oil without addition of asphaltene dispersant. A commercially available dispersant (Miller chemical POLSEN NS-2100) was added to the crude oil at a temperature of 60 ℃ in an amount of 300ppm to give the crude oil to be tested of comparative example 14.

Then, the crude oils to be tested of examples 7 to 12 and comparative examples 7 to 14, which have an actual crude oil content of 0.5g, were taken, n-heptane with different qualities was added, and a spectrophotometer was used to test the change of the light transmittance of each crude oil to be tested with the addition of n-heptane, and the initial flocculation point of asphaltenes in each crude oil to be tested was determined. The initial flocculation point of the asphaltenes was determined as shown in Table 1.

TABLE 1

Examples of the invention	Initial flocculation point	Examples of the invention	Initial flocculation point
				Example 7	13.3	Comparative example 8	8.61
Example 8	13.04	Comparative example 9	10.02
				Example 9	12.21	Comparative example 10	10.95
Example 10	13.94	Comparative example 11	13.49
				Example 11	13.45	Comparative example 12	11.86
Example 12	12.64	Comparative example 13	-7.60
				Comparative example 7	6.49	Comparative example 14	8.58

As can be seen from Table 1, the initial flocculation point of asphaltenes for the crude oil of comparative example 13 is negative, indicating that the crude oil sample is unstable and that asphaltene deposition is present in the oil sample itself. The initial flocculation point of asphaltenes in examples 7 to 12, comparative examples 7 to 12 and comparative example 14 to which the asphaltene dispersant was added was changed to a positive value, indicating that the asphaltene dispersant functions to disperse asphaltenes to different degrees.

Specifically, the asphaltene dispersants of examples 7 to 12, which were added to the asphaltene dispersants of examples 1 to 6, were effective in retarding flocculation of asphaltenes, and the anti-aggregation effect was superior to that of comparative example 14, which used a commercially available dispersant (Miller chemical POLSEN NS-2100). When the mass percent of the phthalic anhydride polyester polyol PS2000 in the asphaltene dispersant is 25-40% and the mass percent of the block polyoxyethylene polyoxypropylene ether amine ED900 is 20-25%, a good asphaltene dispersing effect can be achieved, the content of the phthalic anhydride polyester polyol and the block polyoxyethylene polyoxypropylene ether amine is increased, the asphaltene dispersing effect cannot be obviously improved, and the cost is increased.

The block polyoxyethylene polyoxypropylene ether amine used in example 6 was polyether amine ED600, which had an oxyethyl to oxypropyl molar ratio of about 2:1, and a more lipophilic, but slightly less asphaltene-dispersing effect than polyether amine ED900, which had an oxyethyl to oxypropyl molar ratio of 2.5: 1. Example 12, using the asphaltene dispersant of example 6, had an initial flocculation point for asphaltenes of 12.64, which was lower than the initial flocculation point for asphaltenes of example 7 using example 1.

The asphaltene dispersant of comparative example 1 replaced the aromatic polyester polyol with the aliphatic polyester polyol, lacking a large number of benzene ring groups, and comparative example 7 using this asphaltene dispersant had an initial flocculation point of 6.49, and the asphaltenes in the crude oil aggregated more easily than example 7 using the asphaltene dispersant of example 1, indicating that the presence of benzene ring groups in the asphaltene dispersant can enhance the interaction of the dispersant with the asphaltenes, thereby achieving a better dispersion effect.

In contrast to example 1, the asphaltene dispersant of comparative example 2 replaced the block polyoxyethylene polyoxypropylene ether amine ED900 with polyoxypropylene ether amine D1000. The polyoxypropylene ether amine D1000 had a stronger lipophilicity than the block polyoxyethylene polyoxypropylene ether amine ED900, however, the initial flocculation point of the asphaltenes was 8.61 when the asphaltene dispersant of comparative example 2 was used in comparative example 8, and the anti-aggregation effect was inferior to that of example 7 using the asphaltene dispersant of example 1. The reason is that the mol ratio of the block polyoxyethylene polyoxypropylene ether amine ED900 oxyethyl group to the oxypropyl group is 2.5:1, and the block polyoxyethylene polyoxypropylene ether amine ED900 has appropriate lipophilic and hydrophilic properties and better stabilization effect on asphaltene molecules. Therefore, the ED900 with the molar ratio of the oxyethyl group to the oxypropyl group of 2.5:1 is selected in the asphalt dispersant, and the asphalt dispersant has better dispersion effect.

In contrast to example 1, the asphaltene dispersant of comparative example 3 did not contain the surfactant Span 60. The asphaltene dispersant of comparative example 3 was used in comparative example 9, the initial flocculation point of the asphaltene was 10.02, and the dispersing effect was inferior to that of example 7. The addition of the surfactant is beneficial to the rapid entrance of the asphaltene dispersant into the asphaltene deposit, thereby improving the dissolution and dispersion effects.

In the asphaltene dispersant of comparative example 4, the contents of the phthalic anhydride polyester polyol PS2000 and the block polyoxyethylene polyoxypropylene ether amine ED900 were lower than those of examples 1 to 5, and comparative example 10 using the asphaltene dispersant of comparative example 4 also had a poorer asphaltene dispersing effect than examples 7 to 11 using the asphaltene dispersants of examples 1 to 5.

The content of the block polyoxyethylene polyoxypropylene ether amine ED900 in the asphaltene dispersant of comparative example 5 was further increased, while the effect of dispersing asphaltene was not significantly improved, but the cost was increased, in comparative example 11 using the asphaltene dispersant of comparative example 5, as compared with examples 7 and 11 using the asphaltene dispersants of examples 1 and 5.

In the asphaltene dispersant of comparative example 6, the content of the phthalic anhydride polyester polyol PS2000 was decreased, and the effect of dispersing asphaltenes was decreased in comparative example 12 using the asphaltene dispersant of comparative example 6, compared to examples 7 and 10 using the asphaltene dispersants of examples 1 and 4.

Therefore, it is appropriate to control the mass percent of the aromatic polyester polyol, the mass percent of the block polyoxyethylene polyoxypropylene ether amine, the mass percent of the surfactant and the mass percent of the aromatic hydrocarbon solvent in the asphaltene dispersant to be 35-50%, 20-35%, 10-15% and 20-30%.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The asphaltene dispersant is characterized by comprising the following components in percentage by mass:

2. the asphaltene dispersant according to claim 1, wherein the aromatic polyester polyol has a molecular weight of 500 to 3000.

3. The asphaltene dispersant according to claim 2, wherein the aromatic polyester polyol is selected from one or more of the group consisting of phthalic anhydride polyester polyol PS-450, phthalic anhydride polyester polyol PS-550, phthalic anhydride polyester polyol PS-1000, and phthalic anhydride polyester polyol PS-2000.

4. The asphaltene dispersant according to claim 1, wherein the molar ratio of oxyethyl group to oxypropyl group in the block polyoxyethylene polyoxypropylene ether amine is (2-3): 1.

5. the asphaltene dispersant according to claim 4, wherein the molecular weight of said block polyoxyethylene polyoxypropylene ether amine is 200-1200.

6. The asphaltene dispersant according to claim 5, characterized in that said block polyoxyethylene polyoxypropylene ether amine is selected from one or more of polyetheramine ED600, polyetheramine ED900 and polyetheramine ED 1200.

7. The asphaltene dispersant according to claim 1, wherein the surfactant is selected from one or more of sorbitan fatty acid esters, glycerol monostearate and glycol fatty acid esters.

8. The asphaltene dispersant according to claim 1, characterized by comprising the following components in mass percent:

9. use of an asphaltene dispersant according to any of claims 1 to 8 in crude oil processing.

10. An oil product characterized by containing the asphaltene dispersant according to any one of claims 1 to 8.