Method for improving stable storage of ship loaded with marine biological fuel oil

Abstract

The invention relates to a method for improving storage stability of marine biological fuel oil loaded on a ship, which comprises the following steps of: coating an antioxidant coating on the inner wall of a fuel oil container, and storing the fuel oil by using the fuel oil container; the preparation method of the anti-oxidation coating comprises the following steps: mixing an antioxidant with a polymer coating; or grafting the antioxidant onto the polymer coating. Compared with the prior art, the oxidation stability is improved, the problem that the stability is reduced due to long-time storage of the marine biological fuel oil is solved, and the stable storage time in an oil tank is prolonged especially when the marine biological fuel oil is stored in a ship oil tank.

Description

Technical Field

[0001] The invention belongs to the technical field of marine biofuel oil, and relates to a method for improving the stable storage of marine biofuel oil when a ship is loaded with the marine biofuel oil. Background Art

[0002] With the rapid development of the global economy and the growth of industrial activities, the demand for energy is increasing. However, the large-scale exploitation and use of traditional fossil fuels such as coal and oil will not only produce a large amount of greenhouse gases and cause the greenhouse effect, but also lead to the over-exploitation of earth resources, and eventually face the threat of resource depletion. In this context, countries are constantly working to find and develop new renewable energy sources to reduce their dependence on fossil energy.

[0003] Marine biofuel oil refers to a marine alternative fuel made by mixing marine fuel oil and biodiesel in a certain proportion. Marine biofuel oil contains a certain proportion of long-chain fatty acids from vegetable oil or animal fats and alcohols such as methanol to produce fatty acid methyl esters. It has the characteristics of being renewable, having good combustion performance, and being clean and pollution-free, and is considered an ideal component for marine fuel.

[0004] The flash point, acid value, kinematic viscosity, cetane number, density, water content and other physical and chemical indicators of marine fuel oil are of great significance to the use and storage of marine oil products. my country has strict regulations on the performance indicators of marine fuel oil. However, there is still a lack of relevant standards and specifications for marine biofuel oil, which affects the promotion and application of marine biofuel oil.

[0005] During the period of using marine biofuel oil by ships, the components of marine biofuel oil must be stable, which is a very critical indicator. Because the oxidation stability of biofuel oil refers to the property of biofuel oil to maintain unchanged chemical properties, it is crucial to the stability of ships when storing biofuel oil for a long time.

[0006] Biofuel oil has a potential corrosion effect on ship bulkheads due to its reduced oxidation stability.

[0007] Depending on the raw materials used in the preparation of biofuel oil, the composition of biofuel oil may vary greatly, which may lead to a decrease in its oxidative stability. In particular, long-term exposure to air and high humidity conditions will seriously affect the quality of biofuel oil.

[0008] Biofuel oil has many obvious advantages over petroleum diesel, but due to the presence of some C=C unsaturated bonds in the molecules of its raw oil, it is more susceptible to oxidation than traditional petroleum diesel. The oxidation of biofuel oil not only leads to the appearance of precipitates and changes in physical and chemical properties in the biofuel oil, but the products formed after oxidation also lead to serious usage problems such as the formation of deposits, increased corrosion and blockage of the engine fuel oil injection system. Therefore, oxidation stability is a key issue that must be addressed for biofuel oil.

[0009] At present, the oxidation stability of biofuel oil can be improved by means of preparation structure modification, production technology improvement, etc. However, this may increase the use cost and complicate the process. The present invention can improve the stability without affecting the total composition by adding an antioxidant as the simplest improvement method. Summary of the invention

[0010] The purpose of the present invention is to provide a method for improving the stable storage of marine biofuel oil when loaded on a ship, improving the oxidation stability and avoiding the problem of stability degradation caused by long-term storage of marine biofuel oil, especially when stored in a ship's oil tank, to increase the stable storage time in the oil tank.

[0011] The preliminary research results of the present invention found that the marine biofuel oil was prepared by blending fatty acid methyl esters prepared from waste edible oils, and adding BHA and BHT antioxidants to the marine biofuel oil, which proved to improve the kinematic viscosity, density, flash and oxidation stability, but the calorific value would be reduced, so as an additive, it might cause a decrease in economic efficiency. In addition, marine biofuel oil contains a large amount of saturated fatty acid methyl esters, and the freezing point is usually above 5°C, which may have higher requirements for the use of antioxidants, and the impact is still unknown, especially in cold regions where possible adverse effects have not been clearly identified. In this regard, the present invention improves the lubricity of marine biofuel oil by molecular modification to reduce its freezing point.

[0012] The purpose of the present invention can be achieved by the following technical solutions:

[0013] A method for improving the stable storage of marine biofuel oil when loaded on a ship, comprising: coating an anti-oxidation coating on the inner wall of a fuel oil container, and storing the fuel oil in the fuel oil container;

[0014] The preparation method of the anti-oxidation coating comprises: mixing an antioxidant with a polymer coating; or grafting the antioxidant onto the polymer coating.

[0015] Furthermore, the antioxidant is selected from one or a combination of natural antioxidants or artificially synthesized antioxidants;

[0016] The natural antioxidant is selected from at least one of propyl gallate, protocatechin, tea polyphenols, vitamins or chitosan;

[0017] The synthetic antioxidant is selected from at least one of butylated hydroxyanisole, dibutyl hydroxytoluene, propyl gallate, di-tert-butylhydroquinone or tert-butylhydroquinone.

[0018] In the present invention, the synergistic effect of the two antioxidants is better than that of a single antioxidant.

[0019] Furthermore, the polymer coating is a polycarbonate coating or a polyurethane coating.

[0020] The polymer coating in the method of the present invention is only a carrier of the antioxidant, so its solid content has no effect on improving the antioxidant stability of marine biofuel oil, as long as the coating can be evenly coated on the surface of the container to form a thin film. Preferably, the solid content of the polymer coating in the present invention is 20-30%.

[0021] Furthermore, the content of the antioxidant in the antioxidant coating is not higher than 3wt%.

[0022] In the present invention, the amount of antioxidant added increases, the induction period is prolonged, but the antioxidant can achieve the effect when the amount added is controlled below 3wt%. If the amount of antioxidant added is too high, it will affect the fluidity, sprayability and film-forming properties of the coating liquid. Therefore, the amount of antioxidant added in the present invention is 1-2wt% of the mass of the polymer coating; preferably, the amount of antioxidant added is 1.5-2wt% of the mass of the polymer coating.

[0023] Furthermore, the base material of the polymer coating is a natural polymer material or an artificially synthesized polymer material;

[0024] The natural polymer material is selected from one of starch, cellulose, chitin or chitosan; the synthetic polymer material is selected from one of polyvinyl alcohol, polylactic acid, polytetrafluoroethylene, polyethylene, polypropylene, polystyrene, polymethyl methacrylate, polyvinyl chloride, nylon, polycarbonate, polyurethane or polyethylene terephthalate.

[0025] Furthermore, the antioxidant is grafted onto the polymer coating by an emulsion graft copolymerization method.

[0026] Furthermore, the coating method is airless spraying, air spraying, electrostatic spraying or mechanical dipping.

[0027] Furthermore, the fuel oil container includes a ship oil tank and an oil tank.

[0028] Furthermore, the fuel oil container is a metal container.

[0029] Furthermore, the material of the metal container is E36 grade low alloy ship plate steel or D36 steel.

[0030] Furthermore, the fuel oil is B10-B30 biofuel oil.

[0031] Furthermore, the biofuel oil is a biofuel oil obtained from one or more of waste cooking oil, soybean oil, corn oil, peanut oil, rapeseed oil, palm oil, sesame oil, sunflower oil, sesame oil, cottonseed oil, flax oil, safflower seed oil, hemp oil, sesame oil, camellia seed oil, peony seed oil, walnut oil, coconut oil and olive oil.

[0032] Compared with the prior art, the present invention has the following characteristics:

[0033] The present invention adds an antioxidant to a polymer coating, and uses the polymer compound coating to evenly coat the coating on the inner wall of a ship's oil tank or an oil tank, and forms one or more layers of thin film on the inner surface of the ship's oil tank or the oil tank through bonding, which not only improves some surface functions of the ship's oil tank or the oil tank, but also gives them an antioxidant function, effectively prolongs the oxidation induction period of the marine biofuel oil, and optimizes the oxidation stability of the biofuel oil.

[0034] Unlike adding antioxidants directly, the innovative method of coating antioxidants on the inner wall of the container instead of adding them directly to the biofuel oil can avoid the problem of shipboard crew members not being able to correctly add the appropriate antioxidant ratio, while helping to save additive costs and improve economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A method for improving the antioxidant stability of marine biofuel oil in antioxidant-grafted polymer coatings. DETAILED DESCRIPTION

[0036] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0037] The following are more detailed implementation cases, which further illustrate the technical solutions of the present invention and the technical effects that can be obtained.

[0038] The following examples are to prepare antioxidant coatings by grafting antioxidants (tea polyphenols, chitosan) into polymer coatings of polycarbonate and polyurethane through an emulsion graft copolymerization method. The specific preparation method includes:

[0039] First, the antioxidant was mixed with 50 mL of water and sheared using a high-speed shearing machine to form a uniform antioxidant emulsion, wherein the shear rate was controlled at 8000 r / min, the water bath temperature was controlled at 80°C, and the shearing time was 30 minutes;

[0040] Then, the antioxidant emulsion was added to 500 mL of a polymer coating with a solid content of 30%, and the reaction temperature was controlled at about 70° C. After 2 hours, the coating containing the graft copolymer was subjected to coagulation, dehydration and drying to obtain the final antioxidant coating.

[0041] Embodiment 1:

[0042] A method for improving the antioxidant stability of marine biofuel oil comprises the following steps: adding an antioxidant into a polymer coating, then coating the antioxidant coating on the inner wall of a ship's oil tank and an oil tank, and directly using the dried ship's oil tank and oil tank to store biofuel oil.

[0043] In the antioxidant coating of this embodiment, the polymer coating used is a polycarbonate (grade LXTY1609T-11) aqueous dispersion produced by Luxi Chemical Group Co., Ltd., with a solid content of 30%, the antioxidant is chitosan, and the mass fraction of the antioxidant in the polymer coating is 2wt%. The material of the fuel oil container is D36 steel, and the fuel oil is B24 biofuel oil.

[0044] The coating method is spraying, and the coating thickness is 1 mm.

[0045] Embodiment 2:

[0046] A method for improving the antioxidant stability of marine biofuel oil comprises the following steps: adding an antioxidant into a polymer coating, then coating the antioxidant coating on the inner wall of a ship's oil tank and an oil tank, and directly using the dried ship's oil tank and oil tank to store biofuel oil.

[0047] In the antioxidant coating of this embodiment, the polymer coating used is a polycarbonate (grade LXTY1609T-11) aqueous dispersion produced by Luxi Chemical Group Co., Ltd., with a solid content of 30%, the antioxidant is tea polyphenols, and the mass fraction of the antioxidant in the polymer coating is 2wt%. The material of the fuel oil container is D36 steel, and the fuel oil is B24 biofuel oil.

[0048] The coating method is spraying, and the coating thickness is 1 mm.

[0049] Embodiment 3:

[0050] A method for improving the antioxidant stability of marine biofuel oil comprises the following steps: adding an antioxidant into a polymer coating, then coating the antioxidant coating on the inner wall of a ship's oil tank and an oil tank, and directly using the dried ship's oil tank and oil tank to store biofuel oil.

[0051] In the antioxidant coating of this embodiment, the polymer coating used is a polycarbonate (grade LXTY1609T-11) aqueous dispersion produced by Luxi Chemical Group Co., Ltd., with a solid content of 30%, and the antioxidants are tea polyphenols and chitosan. The mass fraction of the two antioxidants in the polymer coating is 1wt%. The material of the fuel oil container is D36 steel, and the fuel oil is B24 biofuel oil.

[0052] The coating method is spraying, and the coating thickness is 1 mm.

[0053] Comparative Example 1:

[0054] Compared with Example 1, this comparative example differs only in that:

[0055] The polymer coating without antioxidant was coated on the inner wall of the fuel oil container in the same way, and an equal amount of antioxidant was added to the fuel oil.

[0056] The rest is the same as in Example 1.

[0057] Comparative Example 2:

[0058] Compared with Example 1, this comparative example differs only in that:

[0059] The polymer coating without adding antioxidant is applied to the inner wall of the fuel oil container in the same manner, while no antioxidant is added to the fuel oil.

[0060] Application examples:

[0061] This example is used to examine the storage stability of the fuel of Examples 1-4 and the comparative example. The test method is: after the fuel is stored for 30 days, the fuel acid value of the fuel stored in Examples 1-4 and the comparative example is tested using the ASTM D664 method.

[0062] The test results are shown in Table 1.

[0063] Table 1

[0064] Acid value Example 1 1.12mg KOH / g Example 2 1.37mg KOH / g Example 3 1.05mg KOH / g Comparative Example 1 1.55mg KOH / g Comparative Example 2 2.02mg KOH / g

[0065] As can be seen from Table 1, after using antioxidants, the acid value of stored fuel is much lower than that without antioxidants, which indicates that the degree of fuel oxidation is low. After using two antioxidants in combination, the antioxidant effect on fuel is better than using a single antioxidant alone. The method of using polymer coating grafted antioxidant is better than directly adding antioxidants.

[0066] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A method for improving the stable storage of marine biofuel oil when loading a ship, characterized in that: include: Applying an anti-oxidation coating to the inner wall of a fuel oil container and using the fuel oil container to store fuel oil; The preparation method of the anti-oxidation coating comprises: mixing an antioxidant with a polymer coating; or grafting the antioxidant onto the polymer coating.

2. The method for improving the stable storage of marine biofuel oil when loaded on a ship according to claim 1, characterized in that: The antioxidant is selected from one or a combination of natural antioxidants or artificially synthesized antioxidants; The natural antioxidant is selected from at least one of propyl gallate, protocatechin, tea polyphenols, vitamins or chitosan; The synthetic antioxidant is selected from at least one of butylated hydroxyanisole, dibutyl hydroxytoluene, propyl gallate, di-tert-butylhydroquinone or tert-butylhydroquinone.

3. The method for improving the stable storage of marine biofuel oil when loaded on a ship according to claim 1, characterized in that: The polymer coating is a polycarbonate coating or a polyurethane coating.

4. The method for improving the stable storage of marine biofuel oil when loaded on a ship according to claim 1, characterized in that: The content of the antioxidant in the antioxidant coating is not higher than 3 wt %.

5. The method for improving the stable storage of marine biofuel oil when loaded on a ship according to claim 4, characterized in that: The base material of the polymer coating is a natural polymer material or an artificially synthesized polymer material; The natural polymer material is selected from one of starch, cellulose, chitin or chitosan; the synthetic polymer material is selected from one of polyvinyl alcohol, polylactic acid, polytetrafluoroethylene, polyethylene, polypropylene, polystyrene, polymethyl methacrylate, polyvinyl chloride, nylon, polycarbonate, polyurethane or polyethylene terephthalate.

6. The method for improving the stable storage of marine biofuel oil when loaded on a ship according to claim 1, characterized in that: The antioxidant is grafted onto the polymer coating by an emulsion graft copolymerization method.

7. The method for improving the stable storage of marine biofuel oil when loaded on a ship according to claim 1, characterized in that: The coating method is airless spraying, air spraying, electrostatic spraying or mechanical dipping.

8. The method for improving the stable storage of marine biofuel oil when loaded on a ship according to claim 1, characterized in that: The fuel oil container is a metal container.

9. The method for improving the stable storage of marine biofuel oil when loaded on a ship according to claim 1, characterized in that: The fuel oil is biofuel oil.

10. The method for improving the stable storage of marine biofuel oil when loaded on a ship according to claim 9, characterized in that: The biofuel oil is a biofuel oil made from one or more of the following: waste cooking oil, soybean oil, corn oil, peanut oil, rapeseed oil, palm oil, sesame oil, sunflower seed oil, sesame oil, cottonseed oil, flax oil, safflower seed oil, hemp oil, sesame oil, camellia seed oil, peony seed oil, walnut oil, coconut oil, and olive oil.

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