A clean marine fuel oil based on hydro-ethylene tar and a method of preparation

Abstract

The present application belongs to the technical field of marine fuel oil, and particularly relates to a clean marine fuel oil prepared based on ethylene tar hydrogenation product, more particularly to a No. 180 clean marine fuel oil, and further discloses a preparation method thereof. The marine fuel oil is prepared by compounding and blending ethylene tar under hydrogenation treatment, catalytic oil slurry, residue material, dilution light oil and stearate, and has the advantages of low sulfur content, moderate viscosity, good lubricity, good compatibility, good storage stability and low process cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of marine fuel oil, and particularly relates to a clean marine fuel oil prepared based on a hydrogenation product of ethylene tar, more particularly to a No. 180 clean marine fuel oil, and further discloses a preparation method thereof. BACKGROUND

[0002] With the increasing global environmental problems, according to the requirements of the International Maritime Organization, the upper limit of sulfur content in marine fuel is reduced to 0.5% from January 1, 2020. At the same time, with the development trend of about 3.7% annual growth of global shipping freight volume and large-scale development of shipping market, it is predicted that the annual growth rate of marine fuel consumption will be about 1% during this period, and after the implementation of the sulfur limitation policy in 2020, there will be a gap of about 95 million tons / year of low-sulfur heavy marine fuel.

[0003] At present, high-sulfur heavy marine fuel is mainly produced by blending process, and the blending components include low-sulfur crude oil residue, fixed-bed hydrogenation normal residue, catalytic oil slurry, catalytic diesel, catalytic cycle oil, coking wax oil, ethylene tar, etc. From the blending results, it is relatively easy to meet the quality requirements of low-sulfur marine fuel when using low-sulfur crude oil residue and fixed-bed hydrogenation normal residue to blend low-sulfur marine fuel, which is a high-quality low-sulfur marine fuel blending component. However, due to the use of low-sulfur crude oil residue, fixed-bed hydrogenation normal residue and other materials, which can enter the fixed-bed hydrogenation device and catalytic cracking device to produce fuel oil or chemical raw materials and other products with higher value, from the economic value and refinery material balance, it is not the optimal solution to blend low-sulfur marine fuel with low-sulfur crude oil residue and fixed-bed hydrogenation normal residue, and the economic benefit is not ideal. Therefore, from the economic benefit of the refinery, it is of obvious economic advantage to blend low-sulfur marine fuel product with inferior oil such as ethylene tar and catalytic oil slurry as raw material.

[0004] Ethylene tar is a by-product of high-temperature condensation in the process of steam cracking to produce ethylene, about 10%-15% of the ethylene yield. Ethylene tar has complex composition structure, among which the content of unsaturated hydrocarbons such as aromatics and aromatic alkenes is high, resulting in poor oxidation stability, easy deposition of coke under heat, and high condensation degree, poor compatibility with other heavy oil components. However, ethylene tar is a good potential low-sulfur heavy marine fuel blending component due to its rich aromatic hydrocarbons, high calorific value, low ash content, short side chain, high carbon-hydrogen ratio, low heavy metal content, and low sulfur content. Therefore, it is necessary to try to use as many low-value products as possible to improve the utilization value of refinery chemical by-products, reduce the production cost of low-sulfur heavy marine fuel, and stand firm in the competition.

[0005] The low-sulfur heavy marine fuel oil prepared by blending the residue oil, catalytic slurry oil, ethylene tar and additives with the styrene tar of diesel oil reported in the prior art is a low-sulfur heavy marine fuel oil with simple process, energy saving and consumption of low-value catalytic slurry oil. However, the kinematic viscosity of the fuel oil product obtained by the process is low, which cannot meet the standard indicators of the existing market 180# marine fuel oil, and it is difficult to fully meet the use requirements of low-speed diesel engines of large ships, and the blended components of the process are not uniform, which leads to the problem of easy flocculation, and additives need to be added, which increases the process cost. The process of adding heavy residue oil into suitable light oil components for dilution and blending to produce 180# residue type fuel oil is reported, which can meet the index requirements of marine fuel oil in viscosity, density and pour point, but the process also easily causes uneven mixing of components, resulting in asphaltene and oil sludge deposition problems.

[0006] Although the ethylene tar is treated by hydrogenation to improve its properties in the prior art, the viscosity of the marine fuel oil blended by the hydrogenated ethylene tar according to the traditional scheme is low, and the low viscosity will cause poor lubrication, leading to increased wear between precision parts of fuel injection equipment and even seizure, the leakage between the plunger parts of the high-pressure oil pump will increase with the increase of wear gap, which will reduce the flow of the pump configured in the original system, and further cause the diesel engine to not generate full power, the generator to trip, etc. Therefore, how to prepare a marine dye meeting the performance requirements based on the hydrogenated ethylene tar still has technical problems. SUMMARY

[0007] Therefore, the technical problem to be solved by the present application is to provide a clean marine fuel oil prepared based on the hydrogenated ethylene tar product, which has low sulfur content, low process cost, moderate viscosity, good compatibility and good storage stability.

[0008] The second technical problem to be solved by the present application is to provide a preparation method of the above-mentioned marine fuel oil.

[0009] To solve the above technical problems, the clean marine fuel oil prepared based on the hydrogenated ethylene tar according to the present application comprises the following raw material components by weight:

[0010]

[0011] Preferably, the clean marine fuel oil prepared based on the hydrogenated ethylene tar of the present application comprises the following raw material components by weight: 50-60 parts by weight of residue material, 10-15 parts by weight of hydrogenated ethylene tar, 17-22 parts by weight of catalytic slurry oil, 10-15 parts by weight of dilution light oil, 0.5 parts by weight of stearate. In the above-mentioned preferred weight parts of raw materials, based on the synergistic cooperation of each raw material, the fuel oil composition of the present application has low cleanliness, low sulfur content, moderate viscosity, and increased stability and storage stability of the fuel oil, improving the combustion performance and use performance of the fuel oil.

[0012] Specifically, the residue material comprises one or a mixture of several of VRDS normal residue of high-sulfur crude oil refinery, atmospheric and vacuum distillation residual oil of low-sulfur crude oil processing refinery, viscosity reducing residual oil, and viscosity reducing desulfurized residual oil. One or a mixture of two or more of atmospheric and vacuum distillation residual oil, viscosity reducing residual oil, and viscosity reducing desulfurized residual oil. More preferably, VRDS normal residue is used as the residue material, which has high calorific value and good combustion performance, and can better combine with other components in the present application, thereby playing a role in adjusting the performance indicators of the fuel oil.

[0013] Specifically, the catalytic slurry oil is a low-particulate-content clean catalytic slurry oil obtained by treating the bottom oil of the outer dump of the catalytic cracking unit of the refinery with a settling agent. Preferably, the grade of the slurry oil settling agent is GT-1106D, and the settling conditions are preferably as follows: temperature 50-60℃, settling agent addition amount 100-700ppm, settling time 24-36h, and removal of the upper 90% of the slurry oil as a low-silicon-aluminum-content clean catalytic slurry oil for blending the required 180# marine fuel oil. The catalytic slurry oil is a raw material, which makes full use of the low-value-added products of the refinery, reduces the cost of the refinery, and provides an excellent process route.

[0014] Specifically, the dilution light oil comprises a mixture of one or several of ethylene diesel, catalytic diesel, coking diesel, and catalytic cracking light cycle oil. Preferably, catalytic diesel is used.

[0015] Specifically, the hydrogenated ethylene tar is an ethylene tar product obtained by hydrogenation treatment under the following conditions: temperature 240-360℃ (preferably 280℃), pressure 4.0-7.0MPa (preferably 4.0MPa), space velocity 1.0h -1 -1 (preferably 400:1). After hydrogenation, the original odor of the ethylene tar is improved, dienes, olefins, and acetylenes are saturated, asphaltene is greatly reduced, cleanliness is improved, and the problems of compatibility and storage stability of ethylene tar blending are solved, making it more suitable for the processing of marine fuel oil.

[0016] The stearate includes at least one of octadecanoic acid butyl ester, monopentaerythritol tristearate, monopentaerythritol distearate, dipentaerythritol stearate, tripentaerythritol stearate or pentaerythritol stearate. The addition of it makes the colloidal dispersion system of the composition more stable, so that the formulated marine fuel oil has moderate viscosity, density and good lubricating performance, and improves the service performance and storage stability of the fuel oil.

[0017] Specifically, the marine fuel oil is No. 180 marine fuel oil.

[0018] The application further discloses a preparation method of the clean marine fuel oil prepared based on hydrogenated ethylene tar.

[0019] (1) a selected amount of the catalytic diesel oil and stearate are taken and uniformly mixed;

[0020] (2) a selected amount of the catalytic oil slurry and hydrogenated ethylene tar are sequentially added, and heated to 50-70 DEG C, and uniformly mixed;

[0021] (3) a selected amount of the residue quality material is continuously added, and uniformly mixed at 30-50 DEG C, and the clean marine fuel oil prepared based on hydrogenated ethylene tar is obtained.

[0022] Specifically, the preparation method of the clean marine fuel oil prepared based on hydrogenated ethylene tar comprises the following steps:

[0023] In the step (1), the mixing step is controlled at 50-100 rpm medium speed stirring for 20-30 min;

[0024] In the step (2), the mixing step is controlled at 50-100 rpm medium speed stirring for 15-25 min;

[0025] In the step (3), the mixing step is controlled at 200-400 rpm high speed stirring for 15-30 min.

[0026] Specifically, the preparation method of the clean marine fuel oil prepared based on hydrogenated ethylene tar further comprises a step of preparing the hydrogenated ethylene tar, namely a step of carrying out hydrogenation treatment on ethylene tar under the conditions of 240-360 DEG C, pressure 4.0-7.0 MPa, space velocity 1.0 h -1 , and hydrogen-oil ratio 200-400:1.

[0027] Specifically, the preparation method of the clean marine fuel oil prepared based on hydrogenated ethylene tar further comprises a step of carrying out settling treatment on the catalytic oil slurry, namely a step of adding a settling agent to the catalytic oil slurry and carrying out settling at 50-60 DEG C for 24-36 h, and removing the upper 90% of the oil slurry.

[0028] The method of this invention involves heating, stirring, and mixing according to a specific process sequence and preparation conditions to ensure that all materials are fully mixed and interact with each other. Under the action of intermolecular forces of similar compatibility, the compatibility and stability of fuel oil are greatly improved.

[0029] The marine fuel oil of this invention utilizes hydrotreated ethylene tar, blended with catalytic slurry, slag materials, diluted light oil, and stearate. This fuel oil boasts advantages such as low sulfur content, moderate viscosity, good lubricity, good compatibility, good storage stability, and low processing cost. It effectively solves the problems of low viscosity caused by hydrotreated ethylene tar in marine fuel blending, leading to poor lubrication, increased wear and even seizure of precision components in fuel injection equipment, and increased leakage between high-pressure oil pump plunger components due to increased wear clearance. These issues reduce the flow rate of the pumps in the original system, resulting in the diesel engine not producing full power and generator tripping.

[0030] The marine fuel oil described in this invention improves the odor of ethylene tar by hydrogenating it under optimized process conditions, achieving saturation of dienes, olefins, and alkynes, a desulfurization rate of 54%, a viscosity reduction to 27%, a carbon residue reduction of 31%, a significant reduction in asphaltenes (by 38%), and improved cleanliness (from level 5 to level 1). This effectively solves the problems of compatibility and storage stability in blending ethylene tar.

[0031] The marine fuel oil of the present invention is based on a compound blend of hydrogenated ethylene tar, catalytic slurry, slag material, diluted light oil and stearate. The addition of stearate makes the colloidal dispersion system of the composition more stable, so that the blended marine fuel oil has a suitable viscosity, density and good lubrication performance, thereby improving the performance and storage stability of the fuel oil. Attached Figure Description

[0032] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0033] Figure 1 A standard comparison chart for analyzing oil compatibility. Detailed Implementation

[0034] In the following embodiments of the present invention, the catalytic slurry is a catalytic slurry that has undergone sedimentation treatment. Specifically, the bottom oil from the catalytic cracking unit of an oil refinery is taken, and a slurry settling agent (brand name GT-1106D) is added at a concentration of 500 ppm. After thorough mixing, the mixture is subjected to sedimentation treatment at 55°C for 30 hours. The upper 90% of the slurry is then removed as a clean catalytic slurry with low silica and aluminum content for blending the required No. 180 marine fuel oil.

[0035] Preparation Example 1-8

[0036] The ethylene tar raw material was subjected to hydrotreating at 240-360°C, a pressure of 4.0 MPa, a space velocity of 1.0 h -1 , a hydrogen to oil ratio of 200:1, wherein the control temperature of the hydrotreating scheme in Preparation Example 1-8 was 220, 240, 260, 280, 300, 320, 340, and 360°C, respectively, and the untreated ethylene tar raw material was used as a control.

[0037] The conventional physicochemical properties of the ethylene tar hydrotreated product samples in Preparation Example 1-8 and the ethylene tar raw material were analyzed, and the results are shown in Table 1 below.

[0038] Table 1 Analysis results of index properties of ethylene tar before and after hydrotreating

[0039]

[0040]

[0041] As can be seen from the data in Table 1, the higher the temperature of the hydrotreating process, the better the hydrotreating effect, and when the temperature is increased to 300°C, the density, carbon residue, and asphaltene of the hydrotreated ethylene tar product are mutated, the desulfurization rate reaches 66.4%, the viscosity is reduced to 21.2%, the density is reduced by 0.0482 kg / m -3 , and the physicochemical properties of the ethylene tar are greatly improved.

[0042] Preparation Example 9-13

[0043] The ethylene tar raw material was subjected to hydrotreating at 240-360°C, a pressure of 4.0 MPa, a space velocity of 1.0 h -1 , a hydrogen to oil ratio of 400:1, wherein the control temperature of the hydrotreating scheme in Preparation Example 9-11 was 240, 260, 280, 300, and 360°C, respectively, and the untreated ethylene tar raw material was used as a control.

[0044] The hydrogen sulfide, total precipitate, and cleanliness of the ethylene tar hydrotreated product samples in Preparation Example 9-11 and the ethylene tar raw material were analyzed, and the results are shown in Table 2 below.

[0045] Table 2 Analysis results of physicochemical properties of ethylene tar before and after hydrotreating

[0046]

[0047] From the data in Table 2, it can be seen that before stripping, whether the ethylene tar raw material or the hydrogenated product, the hydrogen sulfide content is higher and higher with the increase of hydrogenation temperature, indicating that the hydrogenation is more and more obvious. After stripping, the hydrogen sulfide of both the ethylene tar raw material and the hydrogenated ethylene tar product is less than 1 mg / kg, and the performance indicators are lower than the national control indicators of 2 mg / kg and the internal control indicators of 1.5 mg / kg, respectively. From the cleanliness analysis results, under the conditions of a temperature of 280℃ and a hydrogen to oil ratio of 400:1, the hydrogenated ethylene tar is between 1-2, indicating that the properties of the ethylene tar have been greatly improved.

[0048] Compatibility indicates the ability of a fuel sample to be compatible with other samples when mixed. Ethylene tar has the advantages of high calorific value and low sulfur content, but also has the disadvantages of strong odor, high asphaltene content, poor compatibility with oil slurry, poor stability in storage and application, and environmental odor and potential instability factors in blending marine fuel components.

[0049] The compatibility of the ethylene tar hydrogenation product samples and the ethylene tar raw material with the catalytic oil slurry in Preparation Examples 10-13 above was tested, Figure 1 which is a standard control chart for analyzing oil compatibility (No. 1-No. 5, No. 5 has the worst compatibility), and the test results are shown in Table 3 below.

[0050] Table 3 Compatibility test

[0051] Item Control 2 Preparation Example 10 Preparation Example 11 Preparation Example 12 Preparation Example 13 Compatibility 4 2 2 2 2

[0052] As can be seen from the data in Table 3, the hydrogenation treatment can effectively solve the compatibility problem of ethylene tar when blended with other oil products.

[0053] Example 1

[0054] The clean marine fuel oil prepared based on hydrogenated ethylene tar described in this example includes the following raw material components by weight: 20 parts by weight of catalytic oil slurry, 10 parts by weight of hydrogenated ethylene tar (Preparation Example 11), 10 parts by weight of catalytic diesel, 59.5 parts by weight of VRDS constant residue, and 0.5 parts by weight of n-butyl stearate.

[0055] The preparation method of the No. 180 clean marine fuel oil described in this example includes the following steps:

[0056] (1) Mix the selected amount of the catalytic diesel and n-butyl stearate described above, and stir at a medium speed of 50-100 rpm for 20-30 min until the mixture is uniform;

[0057] (2) Add the selected amount of the catalytic oil slurry and hydrogenated ethylene tar in sequence, heat to 60℃, and continue to stir at a medium speed of 50-100 rpm for 15-25 min until the mixture is uniform;

[0058] (3) Continue to add selected amount of the VRDS constant residue, slowly control the temperature to 40℃, and high-speed stirring at 200-400 rpm for 15-30 min, until the mixture is uniform, and then reduce to room temperature, to obtain.

[0059] Example 2

[0060] The clean marine fuel oil prepared based on the hydrogenated ethylene tar in this example comprises the following raw material components in parts by weight: catalytic oil slurry 20 parts by weight, hydrogenated ethylene tar (Preparation Example 11) 10 parts by weight, catalytic diesel oil 5 parts by weight, VRDS constant residue 64.5 parts by weight, and n-butyl stearate 0.5 parts by weight.

[0061] The preparation method of the 180# clean marine fuel oil in this example is the same as that in Example 1.

[0062] Example 3

[0063] The clean marine fuel oil prepared based on the hydrogenated ethylene tar in this example comprises the following raw material components in parts by weight: catalytic oil slurry 20 parts by weight, hydrogenated ethylene tar (Preparation Example 13) 10 parts by weight, catalytic diesel oil 5 parts by weight, VRDS constant residue 64.5 parts by weight, and n-butyl stearate 0.5 parts by weight.

[0064] The preparation method of the 180# clean marine fuel oil in this example is the same as that in Example 1.

[0065] Example 4

[0066] The clean marine fuel oil prepared based on the hydrogenated ethylene tar in this example comprises the following raw material components in parts by weight: catalytic oil slurry 20 parts by weight, hydrogenated ethylene tar (Preparation Example 11) 10 parts by weight, catalytic diesel oil 10 parts by weight, VRDS constant residue 60 parts by weight, and n-butyl stearate 0.5 parts by weight.

[0067] The preparation method of the 180# clean marine fuel oil in this example is the same as that in Example 1.

[0068] Example 5

[0069] The clean marine fuel oil prepared based on the hydrogenated ethylene tar in this example comprises the following raw material components in parts by weight: catalytic oil slurry 15 parts by weight, hydrogenated ethylene tar (Preparation Example 1) 20 parts by weight, ethylene diesel oil 5 parts by weight, constant vacuum distillation residue 70 parts by weight, and single pentaerythritol tristearate 0.3 parts by weight.

[0070] The preparation method of the 180# clean marine fuel oil in this example is the same as that in Example 1.

[0071] Example 6

[0072] The clean marine fuel oil prepared from the hydrogenated ethylene tar according to the embodiment comprises the following raw material components by weight: catalytic oil slurry 30 parts by weight, hydrogenated ethylene tar (preparation example 8) 10 parts by weight, coking diesel 20 parts by weight, viscosity-reducing residual oil 30 parts by weight, and dipentaerythritol stearate 0.7 parts by weight.

[0073] The preparation method of the 180# clean marine fuel oil according to the embodiment is the same as that of example 1.

[0074] Comparative example 1

[0075] The preparation raw materials and preparation method of the marine fuel oil according to the comparative example are the same as those of example 2, and the only difference is that no corresponding stearate is added.

[0076] Experimental example

[0077] 1. Product performance

[0078] The main performances of the fuel oils prepared in examples 1-3 above were detected respectively, and the fuel oil in example 1 stored for 3 months (according to GB / T17411-2015) was used as a control, and the test results are shown in Table 4 below.

[0079] Table 4 Main properties of products of examples 1-3

[0080]

[0081] As can be seen from the data in Table 4, the various indicators of the marine fuel oil product according to the embodiment meet the internal control index requirements. Due to deep hydrogenation, especially hydrogenation treatment of ethylene tar at 360℃, the properties of ethylene tar are greatly improved, and the viscosity is greatly reduced, so that the blending ratio of catalytic diesel in the marine fuel formula is reduced, and the carbon aromatic index and calorific value are not greatly improved, but the hydrogenation cost is significantly increased, therefore, in actual operation, the generated oil under operation at about 280℃ is preferably used as a blending raw material. After the control product is stored for 3 months, the various indicators are analyzed, and there is basically no change, indicating that the blended marine fuel product according to the embodiment has good stability.

[0082] 2. Lubricating property

[0083] The lubricating properties of the fuel oils in example 2 and comparative example 1 above were investigated respectively, a high-frequency reciprocating rig (HFRR) produced by the British PCS company was used, and the fuel oil lubricity test (abrasion diameter not greater than 460μm) was carried out according to the method of SH / T 0765-2005 (ISO12156-1), and the test results are shown in Table 5.

[0084] Table 5 Lubricity investigation

[0085] Sample Grinding track diameter μm Kinematic viscosity (50°C) / (mm 2 ·s -1 )]]> Comparative Example 1 396 120.3 Example 2 245 157.3

[0086] From the data in Table 5, it can be seen that the lubricity and kinematic viscosity of the marine fuel oil formula described in the application are greatly improved after adding stearate.

[0087] 3. Stability

[0088] Take 1000ml of the blended fuel oil in Example 4 into three sample bottles, respectively marked as No. 1 sample, No. 2 sample and No. 3 sample, and place them still for 5 months. Take the upper and lower parts of the samples respectively, and analyze them respectively. The analysis results are shown in Table 6.

[0089] Table 6 Analysis results of blended fuel oil

[0090]

[0091]

[0092] From the data in Table 6, it can be seen that the blended fuel oil described in the application is placed still for 5 months, and the upper and lower parts are analyzed. Due to the volatilization of light components, some performance indicators change slightly, but all performance indicators meet the requirements of GB / T17411-2015, and the comprehensive performance index determines that the compatibility and stability of the hydrogenated ethylene tar, VRDS constant residue, catalytic oil slurry, catalytic diesel and stearate are all good.

[0093] Obviously, the above examples are only examples for clearly illustrating, but not limit the embodiments. For ordinary skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, it is not necessary and impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A clean marine fuel oil prepared from hydrogenated ethylene tar, characterized in that, The total amount of the fuel oil includes the following raw material components by mass: 15-30 parts by weight of catalytic oil slurry; 30-70 parts by weight of slag material; Dilute the light oil with 5-20 parts by weight; 10-20 parts by weight of hydrogenated ethylene tar; Stearate 0.3-0.7 parts by weight; The hydrogenated ethylene tar is prepared at a temperature of 240-360℃, a pressure of 4.0-7.0 MPa, and a space velocity of 1.0 h⁻¹. -1 The ethylene tar product after hydrogenation treatment under controlled hydrogen-to-oil ratio of 200-400:1; the stearate includes at least one of butyl octadecyl acetate, pentaerythritol tristearate, pentaerythritol distearate, dipentaerythritol stearate, tripentaerythritol stearate or pentaerythritol stearate.

2. The clean marine fuel oil prepared from hydrogenated ethylene tar according to claim 1, characterized in that, The residue material includes one or a mixture of several of the following: VRDS atmospheric residue from high-sulfur crude oil refineries, atmospheric and vacuum distillation residue from low-sulfur crude oil refineries, viscous residue, and viscous desulfurized residue.

3. The clean marine fuel oil prepared from hydrogenated ethylene tar according to claim 1 or 2, characterized in that, The catalytic slurry is a clean catalytic slurry with low particle content obtained by treating the bottom oil of the catalytic cracking unit in an oil refinery with a settling agent.

4. The clean marine fuel oil prepared based on hydrogenated ethylene tar according to claim 1 or 2, wherein the diluted light oil comprises one or a mixture of several of ethylene diesel, catalytic diesel, coking diesel, and catalytic cracking light cycle oil.

5. A method for preparing clean marine fuel oil based on hydrogenated ethylene tar as described in claim 4, characterized in that, Includes the following steps: (1) Take the selected amount of the catalytic diesel and stearate, and mix them evenly; (2) Add the selected amounts of the catalytic oil slurry and hydrogenated ethylene tar in sequence, and heat to 50-70°C to mix evenly; (3) Continue to add the selected amount of the slag material and mix it evenly at 30-50℃ to obtain the final product.

6. The method for preparing clean marine fuel oil based on hydrogenated ethylene tar according to claim 5, characterized in that: In step (1), the mixing step is to control the stirring speed at 50-100 rpm for 20-30 minutes; In step (2), the mixing step is to control the stirring speed at 50-100 rpm for 15-25 minutes; In step (3), the mixing step involves controlling the high-speed stirring at 200-400 rpm for 15-30 minutes.

7. The method for preparing clean marine fuel oil based on hydrogenated ethylene tar according to claim 5 or 6, characterized in that, It also includes the step of preparing the hydrogenated ethylene tar, which involves heating the ethylene tar at 240-360°C, a pressure of 4.0-7.0 MPa, and a space velocity of 1.0 h⁻¹. -1 The steps for hydrotreating under the condition of controlling the hydrogen-to-oil ratio at 200-400:

1.

8. The method for preparing clean marine fuel oil based on hydrogenated ethylene tar according to claim 5 or 6, characterized in that, It also includes a step of settling the catalytic slurry, which includes adding a settling agent to the catalytic slurry and settling it at 50-60°C for 24-36 hours, and then removing the upper 90% of the slurry to obtain the final product.

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