A low-sulfur heavy marine fuel and a method for preparing the same

Abstract

The present application relates to a kind of low sulfur heavy ship fuel and its preparation method, styrene tar and deaggregation solvent are added into mixing tank, fully mixed, after stratification, the upper liquid is recorded as recovery oil F1;Recovery oil F1 enters settling tank, adds settling agent, fully reacts and stratifies after being placed, the upper liquid is recorded as recovery oil F2;Recovery oil F2 enters extraction tank, after fully mixing with catalytic cracking slurry, stratification is placed, the upper liquid is recorded as recovery oil F3;Recovery oil F3 is treated with desolventizer, and low sulfur heavy ship fuel is obtained.The present application utilizes styrene tar to prepare low sulfur heavy ship fuel, realizes the resource utilization of styrene tar, and the prepared ship fuel meets the use requirements, has the advantages of not coking, not blocking, secondary pollution is light etc.

Description

Technical Field

[0001] This invention relates to a low-sulfur heavy marine fuel and its preparation method, belonging to the field of solid waste treatment technology. Background Technology

[0002] my country's Ministry of Transport requires that, starting January 1, 2019, ships entering emission control areas must use low-sulfur fuel oil with a sulfur content not exceeding 0.5 wt%. The International Maritime Organization (IMO) requires that, starting January 1, 2020, all ships navigating the high seas must use low-sulfur fuel oil (IMO 2020). These changes in the sulfur content standards for marine fuel oil will have a profound impact on both domestic and international marine fuel markets. my country's production and supply capacity of low-sulfur marine fuel is limited, with more than half of the market relying on imports. The production volume of low-sulfur marine fuel is extremely mismatched with the rapidly growing volume of foreign trade cargo at ports. Marine fuel mainly consists of two categories: distillate fuels and residue fuels. Residue marine fuel is primarily produced through blending. Blending components mainly originate from high-sulfur residue oil that is difficult to process in refineries, as well as non-ideal byproducts such as catalytic slurry oil and low-quality secondary processed distillate oils (mostly distillation residues). The key to blending is ensuring that viscosity and stability meet quality requirements. High-sulfur residue oil mainly includes atmospheric residue, vacuum residue, and tar from refineries, while diluent oil components mainly include catalytic slurry, catalytic cycle oil, catalytic diesel, coking wax oil, ethylene tar, and lubricating oil solvent refining extract.

[0003] Patent CN110872533A discloses a low-sulfur heavy marine fuel oil and its preparation method, comprising the following raw materials in parts by weight: 40-65 parts of residue oil, 5-15 parts of catalytic slurry oil, 5-20 parts of styrene tar, 5-20 parts of ethylene tar, 5-20 parts of diesel oil, 0.2-1 parts of additive OP-10, and 0.1-0.5 parts of additive AES. The preparation steps are as follows: First, styrene tar is mixed with diesel oil, additive OP-10 (polyoxyethylene octylphenol ether), additive AES (sodium fatty alcohol polyoxyethylene ether sulfate), residue oil, and catalytic slurry oil at medium speed. Then, ethylene tar is added and stirred at high speed to obtain the final product. This invention solves the problem of uneven mixing of styrene tar with other oil products, which easily produces flocculent matter and coking during use. However, this invention uses a simple mixture of several common distillation residues found in existing refineries. To ensure uniform mixing, surfactants (emulsifiers) OP-10 and AES are added to achieve a uniform emulsification effect. The following problems exist: (1) The composition of various distillation residues will change due to changes in refinery operating conditions, that is, the raw materials are unstable; (2) Using surfactants to increase mixing and emulsification effects increases costs and the emulsification and dispersion effects are not very good for catalytic cracking slurry and various tars with extremely high viscosity at low temperatures; (3) The main reason for easy coking mentioned in the patent is the presence of oligomers, unsaturated substances and solid impurities (such as catalyst powder in catalytic cracking slurry). Simply adding surfactants cannot change the composition, and therefore cannot change the defects of easy coking and easy clogging; (4) Styrene tar contains more than 5 wt% nitrogen-containing polymerization inhibitors, which will cause NOx to be generated when the fuel is burned. Although the marine fuel standard does not further specify the nitrogen content, it will still cause certain environmental problems.

[0004] Wang Qi et al. (Research on blending of low-sulfur marine fuel oil under new standards [J]. Modern Chemical Industry, 2020, v.49; No.298(11): 2371-2374) published a method for preparing marine fuel oil by blending vacuum residue, ethylene tar and hydrotreated tail oil, and produced a variety of marine fuels. After testing, some of them met the requirements of sulfur content being less than 0.5wt%, and the viscosity also met the corresponding standards. Because 2.5wt% of surfactant was used in this process, the problem mentioned in point (2) above also exists. Summary of the Invention

[0005] To address the problems of existing methods, this invention provides a low-sulfur heavy marine fuel and its preparation method. This invention utilizes styrene tar to prepare low-sulfur heavy marine fuel, achieving the resource utilization of styrene tar. The prepared marine fuel meets usage requirements and has advantages such as non-coking, non-clogging, and low secondary pollution during use.

[0006] The present invention provides a method for preparing low-sulfur heavy marine fuel, comprising the following steps: (1) adding styrene tar and depolymerization solvent into a mixing tank and mixing thoroughly, allowing the mixture to stand and separate into layers, and then recording the upper layer as recovered oil F1; (2) entering a settling tank, adding a settling agent, allowing the mixture to react fully and stand and separate into layers, and then recording the upper layer as recovered oil F2; (3) entering an extraction tank, adding catalytic cracking slurry and mixing thoroughly, allowing the mixture to stand and separate into layers, and then recording the upper layer as recovered oil F3; (4) performing desolventizing treatment on recovered oil F3 to obtain low-sulfur heavy marine fuel.

[0007] The styrene tar mentioned in step (1) comes from the distillation residue produced during the production of styrene by ethylbenzene dehydrogenation. It mainly includes aromatics, heterocyclic compounds containing N / O and other elements, among which the aromatics mainly include monocyclic aromatics, bicyclic aromatics and fused-ring aromatics.

[0008] The depolymerization solvent mentioned in step (1) is an alkane or a mixture thereof, preferably one or more of C2-C12 straight-chain alkanes, branched alkanes, cycloalkanes, etc., more preferably one or more of pentane, hexane, heptane, octane, nonane, etc.

[0009] The mass ratio of styrene tar to depolymerization solvent in step (1) is 1:1-4, preferably 1:2-3.5.

[0010] The mixing described in step (1) can be achieved by means including but not limited to stirring, forced circulation, etc., that is, by achieving uniform mixing of the substances in the system.

[0011] The settling agent mentioned in step (2) is one or more of the following: sodium bicarbonate solution, ammonia solution, calcium hydroxide solution, sodium hydroxide solution, potassium hydroxide solution, sodium carbonate solution, potassium carbonate solution, etc., with a mass concentration of 2.5%-20%, preferably 5%-15%.

[0012] In step (2), the flocculant is added at a volume ratio of 1:15-120 to recovered oil F1, preferably 1:30-90.

[0013] When adding the settling agent in step (2), it is preferable to add it slowly while stirring to prevent the quality of the recycled polymerization inhibitor from deteriorating due to rapid addition at one time. The stirring speed is 60-200 rpm, preferably 80-120 rpm.

[0014] In step (3), the volume ratio of catalytic cracking slurry to recovered oil F2 is 1:2-15, preferably 1:3-10.

[0015] The solvent removal process described in step (4) is a method to evaporate the solvent mixed in the recovered oil F3, which can be, but is not limited to, a thin-film evaporator.

[0016] The final temperature of the solvent removal process in step (4) is 90-200℃, preferably 120-170℃.

[0017] The low-sulfur heavy marine fuel described in this invention is prepared using the method described above. The sulfur content and other indicators of the prepared low-sulfur heavy marine fuel meet the residual fuel standards specified in GB17411-2015.

[0018] Compared with the prior art, the method of the present invention has the following advantages:

[0019] (1) The present invention uses depolymerization solvent to treat styrene tar, and after the recovered oil reacts with the settling agent, it is then mixed and reacted with catalytic cracking slurry. Finally, after desolventization treatment, low-sulfur heavy marine fuel is obtained. In this way, nitrogen-containing substances such as polymerization inhibitors are converted into salts and removed. At the same time, the easily polymerizable and coking oligomers in styrene tar and catalytic cracking slurry are removed. This not only reduces the viscosity, but also allows the obtained oil to be well mixed even without the presence of emulsifiers.

[0020] (2) Compared with the low-sulfur heavy marine fuel prepared by the prior art, the present invention can obtain low-sulfur heavy marine fuel with a more stable composition, no additives required in the preparation process, no coking or clogging during use, and low secondary pollution.

[0021] (3) The raw materials used in this invention are all common hazardous wastes in refineries. In addition to obtaining ship fuel that meets the standards, the invention also achieves the reduction and recycling of hazardous waste. Attached Figure Description

[0022] Figure 1 This is a schematic flowchart of a method for preparing low-sulfur heavy marine fuel according to the present invention;

[0023] Among them, 1-mixing tank, 2-sedimentation tank, 3-extraction tank, 4-evaporator, 1.1-styrene tar, 1.2-recovered oil F1, 1.3-recovered oil F2, 1.4-recovered oil F3, 1.5-low sulfur heavy marine fuel, 1.6-recovered solvent, 1.7-catalytic cracking slurry. Detailed Implementation

[0024] The method and its effects of the present invention will be further illustrated below with reference to specific embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0025] Unless otherwise specified, the experimental methods used in the following examples are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following examples were purchased from conventional biochemical reagent stores.

[0026] The embodiments of the present invention employ appendices Figure 1The process flow for preparing low-sulfur heavy marine fuel from styrene tar shown mainly includes a mixing tank 1, a settling tank 2, an extraction tank 3, and an evaporator 4. The mixing tank 1 is used to fully mix styrene tar 1.1 with the depolymerization solvent. After settling and separation, the upper layer liquid, denoted as recovered oil F1, enters the settling tank. A settling agent is added, and after full reaction and settling and separation, the upper layer liquid, denoted as recovered oil F2, enters the extraction tank. Catalytic cracking slurry is added, and after full mixing and settling and separation, the upper layer liquid, denoted as recovered oil F3, is then subjected to desolventizing treatment to obtain low-sulfur heavy marine fuel.

[0027] The styrene tar and catalytic cracking slurry in this embodiment of the invention are sourced from a refining and chemical enterprise of Sinopec. The styrene tar mainly comprises aromatics and heterocyclic compounds containing N / O elements, while the catalytic cracking slurry mainly comprises heavy oil, oligomers, and catalytic cracking catalyst powder. The specific compositions of the two raw materials are shown in the table below:

[0028]

[0029] Example 1

[0030] 1000 mL of styrene tar was added to a mixing tank, followed by 3000 mL of a depolymerization solvent, a mixture of n-heptane and n-octane at a mass ratio of 1:1. After thorough mixing and settling, the upper layer was identified as recovered oil F1. Recovered oil F1 was then transferred to a settling tank, where a settling agent was added. This agent consisted of a mixture of 8 wt% sodium hydroxide and sodium carbonate (at a mass ratio of 1:1), with a volume ratio of 1:60 to recovered oil F1. The agent was added slowly while stirring at 80 rpm. After thorough reaction and settling, the upper layer was identified as recovered oil F2. The upper layer F2 was then transferred to an extraction tank, where catalytic cracking slurry was added at a volume ratio of 1:5 to recovered oil F2. After thorough mixing and settling, the upper layer was identified as recovered oil F3. Recovered oil F3 was then transferred to an evaporator for desolventizing at a final temperature of 125°C, yielding 958.17 mL of low-sulfur heavy marine fuel. The test results of the prepared marine fuel are shown in Table 1.

[0031] Example 2

[0032] 1000 mL of styrene tar was added to a mixing tank, followed by 3000 mL of a depolymerization solvent, a mixture of n-pentane and n-hexane at a mass ratio of 1:1. After thorough mixing and settling, the upper layer was the recovered oil F1. Recovered oil F1 was then transferred to a settling tank, where a settling agent, a mixture of 10 wt% sodium bicarbonate and sodium carbonate (mass ratio 1:1), was added at a volume ratio of 1:30 to recovered oil F1. The agent was added slowly while stirring at 100 rpm. After thorough reaction and settling, the upper layer was the recovered oil F2. The upper layer F2 was then transferred to an extraction tank, where catalytic cracking slurry was added at a volume ratio of 1:5 to recovered oil F2. After thorough mixing and settling, the upper layer was the recovered oil F3. Recovered oil F3 was then transferred to an evaporator for desolventizing at a final temperature of 135°C, yielding 881.63 mL of low-sulfur heavy marine fuel. The test results of the prepared marine fuel are shown in Table 1.

[0033] Example 3

[0034] 1000 mL of styrene tar was added to a mixing tank, followed by 3000 mL of a depolymerization solvent, a mixture of n-octane and n-nonane at a mass ratio of 1:4. After thorough mixing and settling, the upper layer was the recovered oil F1. Recovered oil F1 was then transferred to a settling tank, where a settling agent (a mixture of 5 wt% potassium hydroxide solution, at a volume ratio of 1:80) was added slowly while stirring at a rate of 90 rpm. After thorough reaction and settling, the upper layer was the recovered oil F2. The upper layer F2 was then transferred to an extraction tank, where catalytic cracking slurry was added at a volume ratio of 1:3. After thorough mixing and settling, the upper layer was the recovered oil F3. Recovered oil F3 was then transferred to an evaporator for desolventizing at a final temperature of 150°C, yielding 997.0 mL of low-sulfur heavy marine fuel. The test results of the prepared marine fuel are shown in Table 1.

[0035] Example 4

[0036] 1000 mL of styrene tar was added to a mixing tank, followed by 3000 mL of a depolymerization solvent, a mixture of n-hexane and n-heptane at a mass ratio of 1:1. After thorough mixing and settling, the upper layer was identified as recovered oil F1. Recovered oil F1 was then transferred to a settling tank, where a settling agent, a mixture of 8 wt% sodium bicarbonate and potassium bicarbonate solution at a volume ratio of 1:70, was slowly added while stirring at 85 rpm. After thorough reaction and settling, the upper layer was identified as recovered oil F2. The upper layer F2 was then transferred to an extraction tank, where catalytic cracking slurry was added at a volume ratio of 1:10. After thorough mixing and settling, the upper layer was identified as recovered oil F3. Recovered oil F3 was then transferred to an evaporator for desolventizing at a final temperature of 150°C, yielding 965.95 mL of low-sulfur heavy marine fuel. The test results of the prepared marine fuel are shown in Table 1.

[0037] Example 5

[0038] 1000 mL of styrene tar was added to a mixing tank, along with 3000 mL of depolymerization solvent (n-nonane). After thorough mixing and settling, the upper layer was the recovered oil F1. Recovered oil F1 was then transferred to a settling tank, where a settling agent (a mixture of 5 wt% calcium hydroxide solution and ammonia solution) was added at a volume ratio of 1:40. The agent was added slowly while stirring at 95 rpm. After thorough reaction and settling, the upper layer was the recovered oil F2. The upper layer F2 was then transferred to an extraction tank, where catalytic cracking slurry was added at a volume ratio of 1:8. After thorough mixing and settling, the upper layer was the recovered oil F3. Recovered oil F3 was then transferred to an evaporator for desolventizing at a final temperature of 150°C, yielding 951.41 mL of low-sulfur heavy marine fuel. The test results of the prepared marine fuel are shown in Table 1.

[0039] Example 6

[0040] 1000 mL of styrene tar was added to a mixing tank, followed by 3000 mL of depolymerization solvent (isopentane and isooctane in a 1:1 mass ratio). After thorough mixing and settling, the upper layer was the recovered oil F1. Recovered oil F1 was then transferred to a settling tank, where a settling agent (a mixture of 5 wt% sodium bicarbonate and potassium bicarbonate solution, at a volume ratio of 1:50) was added slowly while stirring at 100 rpm. After thorough reaction and settling, the upper layer was the recovered oil F2. The upper layer F2 was then transferred to an extraction tank, where catalytic cracking slurry was added in a 1:3 volume ratio. After thorough mixing and settling, the upper layer was the recovered oil F3. Recovered oil F3 was then transferred to an evaporator for desolventizing at a final temperature of 130°C, yielding 793.88 mL of low-sulfur heavy marine fuel. The test results of the prepared marine fuel are shown in Table 1.

[0041] Comparative Example 1

[0042] Same as Example 1, except that xylene was used as the depolymerization solvent. The test results of the prepared marine fuel are shown in Table 2.

[0043] Comparative Example 2

[0044] Same as Example 1, except that ethyl acetate was used as the depolymerization solvent. The test results of the prepared marine fuel are shown in Table 2.

[0045] Comparative Example 3

[0046] Same as Example 1, except that step (1) was not used; instead, step (2) was used directly for sedimentation treatment. The test results of the prepared ship fuel are shown in Table 2.

[0047] Comparative Example 4

[0048] Same as Example 1, except that styrene tar was directly mixed with catalytic cracking slurry. The test results of the prepared marine fuel are shown in Table 2.

[0049] The low-sulfur heavy marine fuels prepared in the examples and comparative examples were tested according to the various indicators in "Marine Fuel Oil" (GB17411-2015), and the results are shown in Tables 1 and 2.

[0050] Table 1 Summary of Sample Analysis Results from Examples

[0051]

[0052] Table 2 Summary of analytical results for comparative samples

[0053]

[0054] As can be seen from the above, the low-sulfur heavy marine fuel prepared by the method of the present invention meets the current standards.

Claims

1. A method for preparing low-sulfur heavy marine fuel, characterized in that... The process includes the following steps: (1) Styrene tar and depolymerization solvent are added to a mixing tank and mixed thoroughly. After standing and separating into layers, the upper layer is recorded as recovered oil F1; (2) Recovered oil F1 is introduced into a settling tank, a settling agent is added, and after fully reacting and standing and separating into layers, the upper layer is recorded as recovered oil F2; (3) Recovered oil F2 is introduced into an extraction tank, catalytic cracking slurry is added and mixed thoroughly, and after standing and separating into layers, the upper layer is recorded as recovered oil F3; (4) Recovered oil F3 is subjected to desolventization treatment to obtain low-sulfur heavy marine fuel; the depolymerization solvent is one or more of pentane, hexane, heptane, octane, and nonane; the mass ratio of styrene tar to depolymerization solvent is 1:1-4; the volume ratio of catalytic cracking slurry to recovered oil F2 is 1:2-15; the settling agent is one or more of sodium bicarbonate solution, ammonia solution, calcium hydroxide solution, sodium hydroxide solution, potassium hydroxide solution, sodium carbonate solution, and potassium carbonate solution, with a mass concentration of 2.5%-20%.

2. The method according to claim 1, characterized in that: The styrene tar mentioned in step (1) comes from the distillation residue produced during the production of styrene by ethylbenzene dehydrogenation, including aromatics and heterocyclic compounds containing N / O elements, wherein the aromatics include monocyclic aromatics, bicyclic aromatics and polycyclic aromatics.

3. The method according to claim 1 or 2, characterized in that: The mass ratio of styrene tar to depolymerization solvent in step (1) is 1:2-3.

5.

4. The method according to claim 1, characterized in that: The settling agent mentioned in step (2) has a mass concentration of 5%-15%.

5. The method according to claim 1 or 4, characterized in that: In step (2), the flocculant is added at a volume ratio of 1:15-120 to the recovered oil F1.

6. The method according to claim 5, characterized in that: In step (2), the flocculant is added at a volume ratio of 1:30-90 to the recovered oil F1.

7. The method according to claim 1, characterized in that: When adding the settling agent described in step (2), add it slowly while stirring at a stirring rate of 60-200 rpm.

8. The method according to claim 7, characterized in that: In step (2), the stirring speed is 80-120 rpm.

9. The method according to claim 1, characterized in that: The volume ratio of catalytic cracking slurry to recovered oil F2 in step (3) is 1:3-10.

10. The method according to claim 1, characterized in that: The solvent removal process described in step (4) is a method of evaporating the solvent mixed in the recovered oil F3, specifically using a thin-film evaporator.

11. The method according to claim 1, characterized in that: The final temperature of the solvent removal process in step (4) is 90-200℃.

12. The method according to claim 11, characterized in that: The final temperature of the solvent removal process in step (4) is 120-170℃.

13. A low-sulfur heavy marine fuel, characterized in that... It is prepared by the method described in any one of claims 1-12.

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