Fuel oil composition

Abstract

To provide a fuel oil composition having excellent combustion performance due to the inclusion of fatty acid alkyl ester, and also possessing room temperature oil passage performance.SOLUTION: A fuel oil composition comprises a fatty acid alkyl ester having specific properties and a cracked gas oil fraction, each in a content of 15.0 vol.% or more to 35.0 vol.% or less, and 20.0 vol.% or more to 40.0 vol.% or less, respectively, based on a total content of the composition, the fuel oil composition satisfying all of the following: (1) a density at 15°C of 0.8700 g / cm3 or more to 0.8900 g / cm3 or less, (2) a kinematic viscosity at 50°C of 2.000 mm2 / s or more to 4.500 mm2 / s or less, (3) a sulfur content of 0.400 mass% or less, (4) a content of 3-ring or more aromatics of 2.9 vol.% or more, and (5) a residual carbon content of 10% residuum of 0.21 mass% or more to 0.60 mass% or less. A method for producing the fuel oil composition is also provided.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a fuel oil composition. [Background technology]

[0002] Class 1 heavy oil (hereinafter also referred to as "A heavy oil") of JIS K2205:1991, especially Class 1 No. 1 heavy oil (hereinafter also referred to as "low-sulfur A heavy oil") of JIS K2205:1991, has a higher calorific value per unit volume than kerosene, light oil, etc., and can reduce the amount (volume) of fuel oil used. It also has a smaller sulfur content, nitrogen content, and residual carbon content than C heavy oil (Class 3 heavy oil of JIS K2205:1991), so it has a smaller environmental impact. Furthermore, unlike C heavy oil, it does not need to be heated, can be stored and used at room temperature, and has excellent supply stability, so it is widely used as a fuel oil for internal combustion engines such as marine diesel engines and as a fuel oil for external combustion engines such as power generation boilers.

[0003] As fuel oils for ships, fuel oils that satisfy ISO8217 "Petroleum products-Fuels (class F)-Specification of marine fuels" are known. In ISO8217:2017, additional regulations (DF grades: DFA, DFZ and DFB) were added for marine distillate oils with a maximum content of fatty acid methyl esters (FAME) of 7% by volume or less. As fuel oil compositions containing fatty acid methyl esters (FAME), compositions described in Patent Documents 1 to 3 are known. The above Patent Documents 1 to 3 disclose fuel oil compositions for internal combustion engines and fuel oil compositions for external combustion engines that contain a methyl ester of rapeseed oil containing fatty acid methyl esters such as myristic acid methyl ester at a content of 5 to 100% by volume. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2007-231119 A [Patent Document 2] JP 2007-231120 A [Patent Document 3] JP 2007-231121 A Summary of the Invention [Problem to be solved by the invention]

[0005] Fatty acid alkyl esters such as fatty acid methyl esters (FAME) contained in the fuel oil compositions described in Patent Documents 1 to 3 have high combustion performance, and are therefore one of the base oils that are being considered for use as fuel oils. In addition, when fatty acid alkyl esters derived from animals and plants are used, carbon dioxide emissions are reduced, which contributes to the suppression of global warming through reduced carbon dioxide emissions, and is extremely useful from the perspective of environmental protection. Therefore, by using fatty acid alkyl esters such as fatty acid methyl esters (FAME) as base oils, improved combustion performance can be expected, and further, when fatty acid alkyl esters derived from animals and plants are used, the base oil can contribute to environmental protection.

[0006] Incidentally, when a fuel oil composition is used in a ship, particularly in a diesel engine of a ship, the frequency of blockage of the fuel oil filter is likely to increase due to the generation of sludge caused by the aggregation of asphaltene during normal use. Furthermore, when the fuel oil composition is used after long-term storage in a fuel oil tank or the like on the ship, sludge is likely to be generated, and the frequency of blockage tends to increase.

[0007] As a fuel oil composition for ships, fuel oils that satisfy the above-mentioned ISO8217 are known, but they may cause clogging of fuel oil filters. Methods for reducing the frequency of clogging include a method of reducing potential sediment (total sediment aged, ISO 10307-2) to 0.10 mass% or less, and a method of reducing actual sediment (total sediment by hot filtration, ISO 10307-1) to 0.10 mass% or less. However, for fuel oils for ships, particularly distillate oils, the oil passing performance through fuel oil filters after storage at room temperature is not sufficient, and a fuel oil composition that can further reduce the frequency of clogging is required.

[0008] In Japan, it is known that the Japan Fisheries Federation's fuel oil standard for fishing boats requires that the water content and dry sludge content be set to a specified level or less in order to reduce the frequency of blockage in heavy oil A for fishing boats. Thus, marine fuel oil compositions used both at home and abroad are required to further reduce the frequency of blockage, and the requirements for oil passing performance are becoming stricter every year.

[0009] The fuel oil compositions described in the above Patent Documents 1 to 3 focus on reducing unburned matter (smoke) and particulate matter (PM) in exhaust gas, improving calorific value and reducing soot concentration in combustion exhaust gas, as well as reducing sulfur content and improving sludge stability due to the incorporation of a carbon residue imparting agent. However, attention is not paid not only to improving combustion performance but also to improving oil permeability by reducing the frequency of clogging, and there is room for improvement, especially in terms of oil permeability. In addition, ISO8217 sets standards for ship distillate oils with a fatty acid methyl ester (FAME) content of 7% by volume or less, but does not mention low-sulfur A-type heavy oils with a fatty acid alkyl ester content of more than 7% by volume. Low-sulfur A-type heavy oils with a fatty acid alkyl ester content of more than 7% by volume, such as fatty acid methyl ester (FAME), are prone to clogging of fuel oil filters when used after storage at room temperature, and cannot be said to be excellent in terms of fuel oil filter permeability (hereinafter also referred to as "room temperature permeability"). Therefore, there is a demand for further improvements in improving the oil passing performance by reducing the frequency of clogging of fuel oil filters when the fuel oil is used after storage at room temperature.

[0010] The present invention has been made in view of the above circumstances, and has an object to provide a fuel oil composition which contains a fatty acid alkyl ester and thereby has excellent combustion performance as well as room temperature oil passing performance. [Means for solving the problem]

[0011] As a result of intensive research in view of the above problems, the present inventors have found that the problems can be solved by the following invention. That is, the present invention provides a fuel oil composition having the following composition.

[0012] [1] A fuel oil composition comprising a fatty acid alkyl ester satisfying all of the following (a1) to (a3) ​​and a cracked light oil fraction satisfying all of the following (b1) to (b4), wherein the fatty acid alkyl ester is an ester of a fatty acid having from 8 to 22 carbon atoms and an alkyl alcohol having from 1 to 4 carbon atoms, the content of the fatty acid alkyl ester being from 15.0 vol. % to 35.0 vol. % based on the total amount of the composition, and the content of the cracked light oil fraction being from 20.0 vol. % to 40.0 vol. % based on the total amount of the composition, and satisfying all of the following (1) to (5). (a1) Cetane number is 49.0 or more (a2) Acid value is 0.50 mg KOH / g or less (a3) The residual carbon content of 10% residual oil is 0.80% by mass or more and 1.50% by mass or less (b1) The kinetic viscosity at 50°C is 1.700 mm 2 / s or more 3.600mm 2 / s or less (b2) Sulfur content is 0.40% by mass or less (b3) Aromatic content is 50.0% by volume or more (b4) Aromatic content of 3 or more rings is 5.0% by volume or more (1) Density at 15°C is 0.8700 g / cm 3 More than 0.8900g / cm 3 below (2) Kinematic viscosity at 50°C is 2.000mm 2 / s or more 4.500mm 2 / s or less (3) Sulfur content is 0.400% by mass or less (4) Aromatic content of 3 or more rings is 2.9% by volume or more (5) The residual carbon content of 10% residual oil is 0.21% by mass or more and 0.60% by mass or less. [2] The fuel oil composition according to the above [1], wherein the fatty acid alkyl ester is a fatty acid methyl ester. [3] The fuel oil composition according to [1] or [2] above, wherein the fatty acid is a mixed fatty acid containing two or more kinds of fatty acids having 8 to 22 carbon atoms. [4] The fuel oil composition according to [3] above, wherein the mixed fatty acid is obtained from at least one raw material selected from animal oils and vegetable oils. [5] The fuel oil composition according to the above [4], wherein the raw material is waste edible oil. [6] The fuel oil composition according to any one of the above [1] to [5], which is used in an internal combustion engine. [7] A method for producing a fuel oil composition which satisfies all of the following (1) to (5), comprising mixing a fatty acid alkyl ester which is an ester of a fatty acid having from 8 to 22 carbon atoms and an alkyl alcohol having from 1 to 4 carbon atoms and which satisfies all of the following (a1) to (a3) ​​with a cracked light oil fraction which satisfies all of the following (b1) to (b4) so ​​that the content of the fatty acid alkyl ester is from 15.0 to 35.0 vol. % based on the total volume of the composition, and the content of the cracked light oil fraction is from 20.0 to 40.0 vol. % based on the total volume of the composition. (a1) Cetane number is 49.0 or more (a2) Acid value is 0.50 mg KOH / g or less (a3) The residual carbon content of 10% residual oil is 0.80% by mass or more and 1.50% by mass or less (b1) The kinetic viscosity at 50°C is 1.700 mm 2 / s or more 3.600mm 2 / s or less (b2) Sulfur content is 0.40% by mass or less (b3) Aromatic content is 50.0% by volume or more (b4) Aromatic content of 3 or more rings is 5.0% by volume or more (1) Density at 15°C is 0.8700 g / cm 3 More than 0.8900g / cm 3 below (2) Kinematic viscosity at 50°C is 2.000mm 2 / s or more 4.500mm 2 / s or less (3) Sulfur content is 0.400% by mass or less (4) Aromatic content of 3 or more rings is 2.9% by volume or more (5) The residual carbon content of 10% residual oil is 0.21% by mass or more and 0.60% by mass or less. Effect of the Invention

[0013] According to the present invention, it is possible to provide a fuel oil composition which contains a fatty acid alkyl ester and thus has excellent combustion performance and also room temperature oil passing performance. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, the fuel oil composition according to the embodiment of the present invention (hereinafter, may be simply referred to as "the present embodiment") will be specifically described. In this specification, the numerical values ​​of "less than", "more than", and "to" in the description of a numerical range are numerical values ​​that can be arbitrarily combined. For example, when a certain numerical range is described as "A to B" and "C to D", the numerical ranges "A to D" and "C to B" are also included. Furthermore, the numerical values ​​in the examples are numerical values ​​that can be used as upper or lower limits.

[0015] [Fuel oil composition] The fuel oil composition of this embodiment comprises a fatty acid alkyl ester that satisfies all of the following (a1) to (a3) ​​and a cracked light oil fraction that satisfies all of the following (b1) to (b4), wherein the fatty acid alkyl ester is an ester of a fatty acid having from 8 to 22 carbon atoms and an alkyl alcohol having from 1 to 4 carbon atoms, the content of the fatty acid alkyl ester is from 15.0 vol.% to 35.0 vol.% based on the total amount of the composition, and the content of the cracked light oil fraction is from 20.0 vol.% to 40.0 vol.% based on the total amount of the composition, and the fuel oil composition satisfies all of the following (1) to (5). (a1) Cetane number is 49.0 or more (a2) Acid value is 0.50 mg KOH / g or less (a3) The residual carbon content of 10% residual oil is 0.80% by mass or more and 1.50% by mass or less (b1) The kinetic viscosity at 50°C is 1.700 mm 2 / s or more 3.600mm 2 / s or less (b2) Sulfur content is 0.40% by mass or less (b3) Aromatic content is 50.0% by volume or more (b4) Aromatic content of 3 or more rings is 5.0% by volume or more (1) Density at 15°C is 0.8700 g / cm 3 More than 0.8900g / cm 3 below (2) Kinematic viscosity at 50°C is 2.000mm 2 / s or more 4.500mm 2 / s or less (3) Sulfur content is 0.400% by mass or less (4) Aromatic content of 3 or more rings is 2.9% by volume or more (5) The residual carbon content of 10% residual oil is 0.21% by mass or more and 0.60% by mass or less.

[0016] (Composition and properties of fuel oil composition) The fuel oil composition of this embodiment satisfies the composition and properties specified in the following (1) to (5). (1) Density at 15°C The density of the fuel oil composition of this embodiment at 15 ° C. is 0.8700 g / cm 3 More than 0.8900g / cm 3 If the density at 15°C is not within the above range, the combustion performance and the total calorific value may decrease.

[0017] From the viewpoint of improving room temperature oil passing performance and combustion performance, and further improving the total calorific value, the density at 15°C of the fuel oil composition of this embodiment is preferably 0.8740 g / cm 3 More preferably, 0.8750 g / cm 3 More preferably, 0.8770 g / cm 3 The upper limit is preferably 0.8880 g / cm 3 Less than or equal to 0.8850 g / cm 3 More preferably, 0.8830 g / cm 3 The following is the result. In this specification, the density at 15° C. is a value measured in accordance with JIS K 2249-1:2011 (Crude oil and petroleum products-Determination of density-Part 1: Vibration method).

[0018] (2) Kinematic viscosity at 50°C The fuel oil composition of this embodiment has a kinematic viscosity at 50°C of 2.000mm 2 / s or more 4.500mm 2 If the kinetic viscosity at 50°C is not within the above range, the combustion performance may be reduced. In addition, the composition may not be suitable for use in various devices such as pumps and flow meters, and the lubricity may not be ensured, making it impossible to use the composition as a fuel oil composition.

[0019] By making it easier to set the kinematic viscosity at 50°C of the fuel oil composition of the present embodiment within the above range, it is possible to improve combustion performance, make it easier to adapt to the range of use of various equipment, and improve lubricity. From the viewpoint of this, the kinematic viscosity at 50°C is preferably 2.800mm. 2 / s or more, preferably 3.600 mm 2 / s or more, more preferably 3.680 mm 2 / s or more, and the upper limit is preferably 4.300 mm 2 / s or less, preferably 4.100 mm 2 / s or less, more preferably 3.850 mm 2 / s or less. In this specification, the kinematic viscosity at 50° C. is a value measured in accordance with JIS K 2283:2000 (Testing method for kinematic viscosity of crude oil and petroleum products).

[0020] (3) Sulfur content The sulfur content of the fuel oil composition of this embodiment is 0.400% by mass or less. If the sulfur content is not within the above range, corrosion may occur due to an increase in sulfur oxides in exhaust gas, and environmental performance may be reduced due to an increase in the load on the environment. In consideration of suppressing the occurrence of corrosion and improving environmental performance, the sulfur content is preferably 0.380% by mass or less, more preferably 0.350% by mass or less, and even more preferably 0.300% by mass or less. In addition, the lower the sulfur content, the more preferable it is, and there is no particular limit as to the lower limit, but from the viewpoint of improving storage stability and lubricity, it is usually 0.05% by mass or more. In this specification, the content of sulfur other than fatty acid alkyl esters is measured by selecting a measurement method depending on the content, and when the content is 0.01 to 5 mass%, it is a value measured in accordance with JIS K 2541-4:2003 (Crude oil and petroleum products-Determination of sulfur content-Part 4: Radioactive excitation method).

[0021] (4) Aromatic content of 3 or more rings The content of aromatics with three or more rings in the fuel oil composition of this embodiment is 2.9% by volume or more. If the content of aromatics with three or more rings is not within the above range, the storage stability decreases. In particular, from the viewpoint of suppressing the decrease in the storage stability of the fatty acid alkyl ester and improving the storage stability of the fuel oil composition, the content is preferably 3.0% by volume or more, more preferably 3.1% by mass or more, and even more preferably 3.2% by volume or more, and although there is no particular upper limit, it is usually 6.0% by volume or less. In this specification, the aromatic content (single-ring aromatic content, two-ring aromatic content, and three or more ring aromatic content), as well as the saturated content and olefin content, are values ​​measured by the High Performance Liquid Chromatography method specified in JPI-5S-49-2007, Petroleum Products - Hydrocarbon Type Testing Method.

[0022] (5) Carbon Residual in 10% Residual Oil The residual carbon content of the 10% residual oil of the fuel oil composition of this embodiment is 0.21% by mass or more and 0.60% by mass or less. If the residual carbon content of the 10% residual oil exceeds 0.60% by mass, it becomes difficult to maintain the combustion performance, and sludge is easily generated, resulting in a decrease in room temperature oil passing performance. In addition, by making it 0.21% by mass or more, the fuel oil composition of this embodiment can be treated as heavy oil A and is not subject to the light oil delivery tax, so that a tax benefit can be obtained. From the viewpoint of improving the combustion performance and room temperature oil passing performance, and considering the tax benefit, the residual carbon content of the 10% residual oil is preferably 0.22% by mass or more, and the upper limit is preferably 0.50% by mass or less, more preferably 0.45% by mass or less, even more preferably 0.40% by mass or less, and even more preferably 0.38% by mass or less. In this specification, the carbon residue of 10% residual oil is a value measured in accordance with JIS K 2270-2:2009 (Crude petroleum and petroleum products-Determination of carbon residue-Part 2: Micro method) using 10% residual oil prepared in accordance with Appendix A.

[0023] In addition to the properties and composition of (1) to (5) above, the fuel oil composition of this embodiment preferably satisfies at least one of the following (6) to (12), and particularly preferably satisfies all of the following (6) to (12).

[0024] (6) Flash point From the viewpoint of safety in handling, the flash point of the fuel oil composition of the present embodiment is preferably 60.0° C. or higher, more preferably 65.0° C. or higher, and even more preferably 70.0° C. or higher. There is no particular upper limit, but it is usually 100.0° C. or lower. In this specification, the flash point of a substance other than a fatty acid alkyl ester is a value measured in accordance with JIS K 2265-3:2007 (Crude petroleum and petroleum products-Flash point test method-Part 3: Pensky-Martens closed-cell method).

[0025] (7) Cetane number The cetane number of the fuel oil composition of this embodiment is preferably 39.0 or more, more preferably 40.0 or more, even more preferably 40.5 or more, and even more preferably 41.0 or more, and although there is no particular upper limit, it is usually 45.0 or less. When the cetane number is within the above range, the combustion performance is improved. In this specification, the cetane number is a value determined in accordance with JIS K 2280-4:2013 (Petroleum products-Determination of octane number, cetane number and cetane index-Part 4: Cetane number).

[0026] (8) Moisture content The water content of the fuel oil composition of this embodiment is preferably 0.10% by volume or less, more preferably less than 0.10% by volume, and even more preferably 0.05% by volume or less. If the water content is within the above range, the generation of sludge due to an emulsion of asphaltene and water and the occurrence of freezing during storage at room temperature can be suppressed, thereby reducing the frequency of blockage in the fuel oil filter, and improving the room temperature oil passing performance. In this specification, the water content other than fatty acid alkyl esters is a value measured in accordance with JIS K 2275-1:2015 (Crude oil and petroleum products - Determination of water content - Part 1: Distillation method).

[0027] (9) Copper plate corrosion The copper plate corrosion of the fuel oil composition of this embodiment is preferably 1 or less (1a or 1b) in the classification of copper plate in the copper plate judgment, and more preferably 1a. If the copper plate corrosion is 1 or less, corrosion of various auxiliary machines such as fuel oil tanks, piping, diesel engines, and pumps installed therein can be prevented, thereby enabling more stable operation of various devices such as internal combustion engines and external combustion engines. In this specification, copper plate corrosion is measured in accordance with JIS K 2513:2000 (Petroleum products - Copper plate corrosion test method) at a test temperature of 50°C and for a test time of 3 hours.

[0028] (10) Acid value The acid value of the fuel oil composition of this embodiment is preferably 0.05 mgKOH / g or less, more preferably less than 0.05 mgKOH / g, and even more preferably 0.03 mgKOH / g or less. The smaller the acid value, the more preferable it is, and there is no particular lower limit, and 0.0 mgKOH / g is particularly preferable. When the acid value is within the above range, the frequency of blockage in the fuel oil filter can be reduced by suppressing sludge generation, improving the normal temperature oil passing performance, and further suppressing corrosion of components such as storage tanks and piping during normal temperature storage. In this specification, the acid value is a value measured in accordance with JIS K 2501:2003 (Petroleum products and lubricants -- Determination of neutralization number).

[0029] (11) Pour point The pour point of the fuel oil composition of this embodiment is preferably −0.0° C. or lower, more preferably −2.5° C. or lower, and even more preferably −5.0° C. or lower, and although there is no particular lower limit, it is usually −35.0° C. or higher. When the pour point is within the above range, the fluidity in a storage tank or in piping at low temperatures is improved, and the handleability is also improved. In this specification, the pour point is a value measured in accordance with JIS K 2269:1987 (Testing method for pour point and cloud point of crude oil and petroleum products).

[0030] (12)Nitrogen content The nitrogen content of the fuel oil composition of the present embodiment is preferably 200 ppm by mass or less, more preferably 190 ppm by mass or less, even more preferably 180 ppm by mass or less, and even more preferably 175 ppm by mass or less, and although there is no particular lower limit, it is usually 30 ppm by mass or more. If the nitrogen content is within the above range, NOx emissions can be reduced, improving environmental performance. In this specification, the nitrogen content is a value measured in accordance with JIS K 2609:1998 (Crude petroleum and petroleum products -- Determination method for nitrogen content).

[0031] (Fatty acid alkyl ester) The fuel oil composition of this embodiment satisfies all of the following (a1) to (a3) ​​and contains a fatty acid alkyl ester, which is an ester of a fatty acid having from 8 to 22 carbon atoms and an alkyl alcohol having from 1 to 4 carbon atoms, in an amount of from 15.0 vol. % to 35.0 vol. % based on the total amount of the composition. (a1) Cetane number is 49.0 or more (a2) Acid value is 0.50 mg KOH / g or less (a3) The residual carbon content of 10% residual oil is 0.80% by mass or more and 1.50% by mass or less

[0032] (a1) Cetane number The cetane number of the fatty acid alkyl ester is 49.0 or more. The fatty acid alkyl ester is known as an oil type with a high cetane number, and by using the fatty acid alkyl ester, the cetane number of the fuel oil composition of the present embodiment can be improved, and the combustion performance can be improved. Therefore, if the cetane number of the fatty acid alkyl ester is less than 49.0, the effect of improving the cetane number of the fuel oil composition of the present embodiment cannot be sufficiently obtained, and the combustion performance may be reduced. From the viewpoint of improving combustion performance, the cetane number of the fatty acid alkyl ester is preferably 50.0 or more, more preferably 51.0 or more. There is no particular upper limit, and it is usually 70.0 or less.

[0033] (a2) Acid value The acid value of the fatty acid alkyl ester is 0.50 mgKOH / g or less. If the acid value of the fatty acid alkyl ester is not within the above range, the frequency of clogging in the fuel oil filter is likely to occur due to the suppression of sludge generation, which reduces the room temperature oil passing performance, and corrosion of components such as storage tanks and piping during storage at room temperature may occur. From the viewpoint of improving the room temperature oil passing performance and suppressing corrosion of components, the acid value of the fatty acid alkyl ester is preferably 0.48 mgKOH / g or less, more preferably 0.47 mgKOH / g or less, and even more preferably 0.46 mgKOH / g or less, with no particular lower limit and usually 0.05 mgKOH / g or more.

[0034] (a3) Carbon residue of 10% residual oil The carbon residue of the 10% residual oil of the fatty acid alkyl ester is 0.80% by mass or more and 1.50% by mass or less. If the carbon residue of the 10% residual oil of the fatty acid alkyl ester is not within the above range, it is difficult to make the carbon residue of the 10% residual oil of the fuel oil composition of this embodiment 0.21% by mass or more and 0.60% by mass or less, making it difficult to maintain combustion performance. In addition, it is difficult to reduce the frequency of clogging in the fuel oil filter, and room temperature oil passing performance may decrease. By making it easier to make the residual carbon content of the 10% residual oil of the fuel oil composition of this embodiment 0.21 mass% or more and 0.60 mass% or less, from the viewpoint of improving combustion performance and room temperature oil passing performance, the residual carbon content of the 10% residual oil of the fatty acid alkyl ester is preferably 0.85 mass% or more, more preferably 0.90 mass% or more, even more preferably 1.00 mass% or more, and even more preferably 1.05 mass% or more, and the upper limit is preferably 1.40 mass% or less, more preferably 1.30 mass% or less, even more preferably 1.20 mass% or less, and even more preferably 1.10 mass% or less. In addition, it becomes easier to enjoy tax benefits.

[0035] (Fatty acids and alkyl alcohols) A fatty acid alkyl ester is, in a broad sense, an ester of a fatty acid and an alkyl alcohol. The fatty acid alkyl ester used in the present embodiment is an ester of a fatty acid having 8 to 22 carbon atoms and an alkyl alcohol having 1 to 4 carbon atoms, and satisfies all of the above (a1) to (a3).

[0036] As the fatty acid, either saturated or unsaturated fatty acid can be used. Among fatty acids having 8 to 22 carbon atoms, representative and preferred examples of saturated fatty acids include caprylic acid, pelargonic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, palmitoleic acid, margaric acid, stearic acid, nonadecylic acid, arachidic acid, heneicosylic acid, and behenic acid.

[0037] Representative preferred examples of unsaturated fatty acids include monounsaturated fatty acids such as myristoleic acid, palmitoleic acid, oleic acid, eicosenoic acid, and erucic acid; and polyunsaturated fatty acids such as linoleic acid, linolenic acid, stearidonic acid, eicosadienoic acid, mead acid, arachidonic acid, eicosapentaenoic acid, docosadienoic acid, docosapentaenoic acid, and docosahexaenoic acid.

[0038] The fatty acid may be one kind or a mixed fatty acid containing two or more kinds. The fatty acid alkyl ester may be any of the above (a1) to (a3) ​​and the following (a4) to (a5). 11 In order to easily satisfy all of the above requirements and to improve the combustion performance and room temperature oil passing performance, it is preferable to use a mixed fatty acid containing two or more kinds of fatty acids. That is, it is preferable to use two or more fatty acid alkyl esters using a mixed fatty acid containing two or more kinds of fatty acids as described below. Although the above fatty acids are representative examples of straight-chain fatty acids, the fatty acids may be either straight-chain or branched-chain fatty acids as long as they have 8 or more and 22 or less carbon atoms.

[0039] Examples of the alkyl alcohol having 1 to 4 carbon atoms include methanol, ethanol, propanol, and butanol. Propanol and butanol may have a straight chain or a branched chain. The fatty acid alkyl esters are the above (a1) to (a3) ​​and the following (a4) to (a 11 ) to improve combustion performance and room temperature oil passing performance, and in consideration of ease of production of the fatty acid alkyl ester, the carbon number is preferably 3 or less, more preferably 2 or less, that is, more preferably methanol or ethanol, and particularly preferably methanol. Therefore, the fatty acid alkyl ester used in this embodiment is particularly preferably a fatty acid methyl ester.

[0040] In the present embodiment, the fatty acid alkyl ester may be used alone or in combination of two or more. 11 ) and improve the combustion performance and room temperature oil passing performance, it is preferable to use two or more of them in combination. Examples of combinations of two or more types include two or more fatty acid alkyl esters formed from two or more fatty acids and one type of alkyl alcohol, two or more fatty acid alkyl esters formed from one type of fatty acid and two or more alkyl alcohol, and two or more fatty acid alkyl esters formed from two or more fatty acids and two or more alkyl alcohols, and any of these may be used in this embodiment.

[0041] The fatty acid alkyl esters are the above (a1) to (a3) ​​and the following (a4) to (a 11 ) and improve the combustion performance and room temperature oil passing performance, it is preferable to use two or more fatty acid alkyl esters of two or more fatty acids and one alkyl alcohol. When using two or more fatty acids, for example, the fatty acids exemplified above may be mixed and used, or a mixed fatty acid containing two or more fatty acids may be used. Preferred examples of mixed fatty acids include fatty acids obtained from raw materials such as animal oils, vegetable oils, etc. By using fatty acids derived from animals and plants obtained from these raw materials, it is possible to contribute to the suppression of global warming by reducing carbon dioxide emissions, and is extremely useful from the viewpoint of environmental protection.

[0042] Representative and preferred examples of animal oils that can be used as raw materials for mixed fatty acids include beef tallow, lard, mutton tallow, whale oil, fish oil, liver oil, etc. Representative and preferred examples of vegetable oils include linseed oil, safflower oil, sunflower oil, soybean oil, corn oil, cottonseed oil, sesame oil, olive oil, castor oil, peanut oil, coconut oil, palm kernel oil, rapeseed oil, rice bran oil, etc. When using a naturally derived raw material such as an animal oil or a vegetable oil, a pretreatment may be carried out as necessary before preparing a fatty acid alkyl ester by esterification with an alkyl alcohol. For example, the pretreatment may be carried out by purification such as distillation or clay treatment.

[0043] When two or more fatty acids are used, the two or more fatty acid alkyl esters preferably include fatty acid alkyl esters of an unsaturated fatty acid having 18 carbon atoms and an alkyl alcohol, and among the unsaturated fatty acids having 18 carbon atoms, it is more preferable to include fatty acid alkyl esters of oleic acid, linoleic acid, and linolenic acid, i.e., oleic acid alkyl esters, linoleic acid alkyl esters, and linolenic acid alkyl esters. In this case, the total content of the fatty acid alkyl ester of an unsaturated fatty acid having 18 carbon atoms and an alkyl alcohol contained in the fatty acid alkyl ester is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, and even more preferably 80% by mass or more, and although there is no particular upper limit, it is preferable to set it to 95% by mass or less. When the total content of the fatty acid having 18 carbon atoms is within the above range, the fatty acid alkyl ester can be prepared according to the above (a1) to (a3) ​​and further the following (a4) to (a5). 11 ) can be easily satisfied, thereby improving the combustion performance and room temperature oil passing performance.

[0044] The raw material of the mixed fatty acid is preferably vegetable oil, and more preferably rapeseed oil.The raw material of the mixed fatty acid is preferably waste edible oil, more preferably waste edible oil containing vegetable oil, and more preferably waste edible oil containing rapeseed oil, that is, vegetable oil containing rapeseed oil.By adopting waste edible oil for animal and vegetable oil, it is possible to avoid competition with food and to protect the environment by reusing waste. Like the above-mentioned naturally derived raw materials such as animal oils and vegetable oils, waste edible oils may be pretreated as necessary before being esterified with alkyl alcohol to prepare fatty acid alkyl esters. For example, pretreatment by purification such as distillation or clay treatment may be performed.

[0045] In the present embodiment, when fatty acids derived from animals and plants are used as the mixed fatty acids, they may contain fatty acids other than fatty acids having 8 to 22 carbon atoms, i.e., fatty acids having 7 or less and 23 or more carbon atoms. In this case, the content of fatty acids having 8 to 22 carbon atoms contained in the mixed fatty acids is preferably 90% by mass or more, more preferably 92% by mass or more, and even more preferably 95% by mass or more. That is, the content of fatty acids other than fatty acids having 8 to 22 carbon atoms is preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 5% by mass or less, and the lower limit is preferably as low as possible, and is not particularly limited, but is usually 0.5% by mass or more.

[0046] In addition to the above properties and composition (a1) to (a3), the fatty acid alkyl ester further has the following properties (a4) to (a 11 It is preferable that at least one of the following (a4) to (a 11 ) is preferably satisfied.

[0047] (a4) Density at 15°C The density of the fatty acid alkyl ester at 15° C. is preferably 0.8700 g / cm 3 More preferably, 0.8800 g / cm 3 More than 0.8830g / cm 3 The upper limit is preferably 0.9000 g / cm 3 Less than or equal to 0.8900 g / cm 3 More preferably, 0.8880 g / cm 3 When the density at 15°C is within the above range, the density at 15°C of the fuel oil composition of this embodiment is 0.8700 g / cm or less. 3 More than 0.8900g / cm 3 Therefore, the combustion performance and room temperature oil passing performance are improved, and the total calorific value is also improved.

[0048] (a5) Kinematic viscosity at 50°C The kinetic viscosity of the fatty acid alkyl ester at 50°C is preferably 3.000 mm 2 / s or more, preferably 3.200 mm2 / s or more, more preferably 3.500 mm 2 / s or more, and the upper limit is preferably 4.500 mm 2 / s or less, preferably 4.200 mm 2 / s or less, more preferably 3.800 mm 2 When the kinetic viscosity at 50°C is within the above range, the kinetic viscosity at 50°C of the fuel oil composition of this embodiment is 2.000mm / s or less. 2 / s or more 4.500mm 2 / s or less, improving combustion performance, making it easier to adapt to the range of use of various equipment such as pumps and flow meters, and improving lubricity.

[0049] (a6) Sulfur content The sulfur content of the fatty acid alkyl ester is preferably 3 ppm by mass or less, more preferably 2.5 ppm by mass or less, and the lower limit is not particularly limited because the lower limit is the more preferable. If the sulfur content is within the above range, the sulfur content of the fuel oil composition of the present embodiment can be easily set to 0.400% by mass or less, so that the occurrence of corrosion can be further suppressed and environmental performance can be improved. In this specification, the sulfur content of the fatty acid alkyl ester is a value measured in accordance with JIS K 2541-6:2013 (Crude oil and petroleum products-Determination of sulfur content-Part 6: Ultraviolet fluorescence method).

[0050] (a7) Flash point From the viewpoint of safety in handling, the flash point of the fatty acid alkyl ester is preferably 100.0° C. or higher, more preferably 130.0° C. or higher, and even more preferably 150.0° C. or higher. There is no particular upper limit, but it is usually 200.0° C. or lower. In this specification, the flash point of the fatty acid alkyl ester is a value measured in accordance with JIS K 2265-2:2007 (Crude petroleum and petroleum products-Flash point test method-Part 2: Rapid equilibrium closed cell method).

[0051] (a8) Moisture content The water content of the fatty acid alkyl ester is preferably 1000 mg / kg or less, more preferably 500 mg / kg or less, and even more preferably 250 mg / kg or less, and although there is no particular lower limit, it is usually 100 mg / kg or more. When the water content is within the above range, the generation of sludge and the occurrence of freezing can be suppressed, and the frequency of clogging can be reduced, thereby improving the normal temperature oil passing performance. In this specification, the water content of the fatty acid alkyl ester is a value measured in accordance with JIS K 2275-2:2015 (Crude oil and petroleum products-Determination of water content-Part 2: Karl Fischer volumetric titration method).

[0052] (a9) Copper plate corrosion The copper plate corrosion of the fatty acid alkyl ester is preferably 1 or less (1a or 1b) in the classification of copper plate in the evaluation of copper plate, and more preferably 1a. If the copper plate corrosion is 1 or less, corrosion of various auxiliary machines can be prevented, and more stable operation of various devices such as internal combustion engines and external combustion engines can be achieved.

[0053] (a 10 ) Pour point The pour point of the fatty acid alkyl ester is preferably −0.0° C. or lower, more preferably −2.5° C. or lower, and although there is no particular lower limit, it is usually −20.0° C. or higher. When the pour point is within the above range, the fluidity in a storage tank or in a pipe at low temperatures is improved, and the handleability is also improved.

[0054] (a 11 ) Compositional analysis The composition of fatty acid alkyl esters can be analyzed by gas chromatography using a flame ionization detector (FID) in accordance with "2.4.21.3-77 Fatty acid composition (FID temperature-programmed gas chromatography method)" in the Standard Methods for Analysis of Fats, Oils and Related Materials (established by the Japan Oil Chemists' Society in 1993). As described above, the fatty acid alkyl ester preferably includes a fatty acid alkyl ester of an alkyl alcohol and a mixed fatty acid containing at least an unsaturated fatty acid having 18 carbon atoms, particularly oleic acid, linoleic acid, and linolenic acid. The total content of the fatty acid alkyl ester of an alkyl alcohol and a mixed fatty acid containing at least oleic acid, linoleic acid, and linolenic acid based on the total amount of the fatty acid alkyl ester is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, and even more preferably 80% by mass or more, and although there is no particular upper limit, it is preferably 95% by mass or less.

[0055] When the fatty acid alkyl ester contains two or more kinds of fatty acid alkyl esters, it is preferable that they contain at least an oleic acid alkyl ester, a linoleic acid alkyl ester, and a linolenic acid alkyl ester (a fatty acid alkyl ester of an unsaturated fatty acid having 18 carbon atoms and an alkyl alcohol) as described above. It is more preferable that the composition further contains a stearic acid alkyl ester (a fatty acid alkyl ester of a saturated fatty acid having 18 carbon atoms and an alkyl alcohol), and even more preferable that the composition further contains a palmitic acid alkyl ester (a fatty acid alkyl ester of a saturated fatty acid having 16 carbon atoms and an alkyl alcohol), and even more preferable that the composition further contains an arachidic acid alkyl ester and an erucic acid alkyl ester (a fatty acid alkyl ester of a saturated fatty acid having 20 or 22 carbon atoms and an alkyl alcohol), as well as an eicosenoic acid alkyl ester and a behenic acid alkyl ester (a fatty acid alkyl ester of an unsaturated fatty acid having 20 or 22 carbon atoms and an alkyl alcohol), and even more preferable that the composition further contains at least one selected from a caprylic acid alkyl ester, a capric acid alkyl ester, a lauric acid alkyl ester, and a myristic acid alkyl ester.

[0056] (Fatty acid alkyl ester content) The content of the fatty acid alkyl ester based on the total amount of the composition is 15.0% by volume or more and 35.0% by volume or less. If the content of the fatty acid alkyl ester is less than 15.0% by volume, the combustion performance decreases, and if it exceeds 35.0% by volume, the room temperature oil passing performance decreases. From the viewpoint of improving the combustion performance and room temperature oil passing performance, the content of the fatty acid alkyl ester based on the total amount of the composition is preferably 17.5% by volume or more, and the upper limit is preferably 32.5% by volume or less.

[0057] (Light cracked oil fraction) The fuel oil composition of this embodiment contains a cracked light oil fraction in an amount of 20.0% by volume or more and 40.0% by volume or less based on the total volume of the composition. The cracked light oil fraction is a catalytically cracked light oil fraction obtained by fluid catalytic cracking of atmospheric distillation residue oil and / or vacuum distillation residue oil. The cracked light oil fraction used in this embodiment is one of the above fractions that satisfies the properties and composition of the following (b1) to (b4). (b1) The kinetic viscosity at 50°C is 1.700 mm 2 / s or more 3.600mm 2 / s or less (b2) Sulfur content is 0.40% by mass or less (b3) Aromatic content is 50.0% by volume or more (b4) Aromatic content of 3 or more rings is 5.0% by volume or more

[0058] (b1) Kinematic viscosity at 50°C The kinematic viscosity of the cracked light oil fraction at 50°C is 1.700mm 2 / s or more 3.600mm 2 If the kinematic viscosity at 50°C is not within the above range, the kinematic viscosity at 50°C of the fuel oil composition of this embodiment is set to 2.000mm / s or less. 2 / s or more 4.500mm 2 / s or less, the combustion performance may decrease, it may become difficult to conform to the operating range of various equipment such as pumps and flow meters, and lubricity may decrease. By making it easier to set the kinematic viscosity at 50°C of the fuel oil composition of this embodiment within the above range, it is possible to improve combustion performance, make it easier to adapt to the range of use of various equipment, and improve lubricity. From the viewpoint of this, it is preferable to set the kinematic viscosity at 50°C of the fuel oil composition of this embodiment within the above range. 2 / s or more, preferably 2.100 mm 2 / s or more, and the upper limit is preferably 3.400 mm 2 / s or less, preferably 3.200 mm 2 / s or less.

[0059] (b2) Sulfur content The sulfur content of the cracked light oil fraction is 0.400% by mass or less. If the sulfur content is not within the above range, it is difficult to make the sulfur content of the fuel oil composition of the present embodiment 0.400% by mass or less, so it is difficult to suppress the occurrence of corrosion, and environmental performance may be reduced. In order to suppress the occurrence of corrosion and improve environmental performance by making it easier to make the sulfur content of the fuel oil composition of this embodiment 0.400 mass% or less, the sulfur content of the cracked light oil fraction is preferably 0.300 mass% or less, more preferably 0.250 mass% or less. The lower limit is preferably as low as possible, and although there is no particular limit, it is usually 0.05 mass% or more.

[0060] (b3) Aromatic content The aromatic content of the cracked light oil fraction is 50.0% by volume or more. Here, the aromatic content refers to the total content of one-ring aromatics, two-ring aromatics, and three or more ring aromatics. If the aromatic content is not within the above range, it is not possible to prevent the generation of sludge from clogging the fuel oil filter, which usually leads to a decrease in oil passing performance and may also lead to a decrease in combustion performance. From the viewpoint of further suppressing fuel oil filter clogging due to sludge generation, thereby improving normal oil passing performance and improving combustion performance, the content is preferably 60.0 vol.% or more, more preferably 65.0 vol.% or more, and the upper limit is preferably 85.0 vol.% or less.

[0061] (b4) Aromatic content with 3 or more rings The content of aromatics with three or more rings in the cracked light oil fraction is 5.0% by volume or more. If the content of aromatics with three or more rings is not within the above range, it is difficult to make the content of aromatics with three or more rings in the fuel oil composition of this embodiment 2.9% by volume or more, which may result in reduced storage stability. In the fuel oil composition of this embodiment, the aromatic content of 3 or more rings is easily adjusted to 2.9% by volume or more, and from the viewpoint of improving storage stability, the aromatic content is preferably 6.0% by volume or more, and more preferably 7.0% by volume or more, with no particular upper limit, and is usually 15.0% by volume or less.

[0062] The cracked light oil fraction has the properties and composition (b1) to (b4) described above, and further has the properties (b5) to (b6) described below. 14 It is preferable that at least one of the following (b5) to (b 14 ) is preferably satisfied.

[0063] (b5) Density at 15°C The density of the cracked light oil fraction at 15°C is preferably 0.9000 g / cm 3 More preferably, 0.9100 g / cm 3 More preferably, 0.9120 g / cm 3 That's all. The upper limit is preferably 0.9400 g / cm 3 Less than or equal to 0.9300 g / cm 3 More preferably, 0.9200 g / cm 3 When the density at 15°C is within the above range, the kinematic viscosity at 15°C of the fuel oil composition of this embodiment is 0.8700 g / cm or less. 3 More than 0.8900g / cm 3 Therefore, the normal temperature oil passing performance and combustion performance are improved, and further the total calorific value is improved.

[0064] (b6) Flash point From the viewpoint of improving safety in handling, the flash point of the cracked light oil fraction is preferably 65.0° C. or higher, more preferably 70.0° C. or higher.

[0065] (b7) Carbon residue of 10% residual oil The residual carbon content of the 10% residual oil of the cracked light oil fraction is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and the upper limit is preferably 0.20% by mass or less. If the residual carbon content of the 10% residual oil is within the above range, the residual carbon content of the 10% residual oil of the fuel oil composition of this embodiment can be easily set to 0.21% by mass or more and 0.60% by mass or less, thereby improving the combustion performance and room temperature oil passing performance. In addition, it is easier to enjoy tax benefits.

[0066] (b8) Cetane number The cetane number of the cracked light oil fraction is preferably 20.0 or more, more preferably 25.0 or more, and there is no particular upper limit, but it is usually not more than 50.0. If the cetane number is within the above range, the combustion performance is improved.

[0067] (b9) Moisture content The water content of the cracked light oil fraction is preferably 0.10% by volume or less, more preferably less than 0.10% by volume, and even more preferably 0.05% by volume or less. When the water content is within the above range, the generation of sludge and the occurrence of freezing can be suppressed, and the frequency of blockage can be reduced, thereby improving the normal temperature oil passing performance.

[0068] (b 10 ) Copper plate corrosion The copper plate corrosion of the cracked light oil fraction is preferably classified as 1 or less (1a or 1b), and more preferably 1a, in terms of the copper plate classification in the copper plate judgment. If the copper plate corrosion is 1 or less, corrosion of various auxiliary machines can be prevented, and more stable operation of various devices such as internal combustion engines and external combustion engines can be achieved.

[0069] (b 11 ) Acid value The acid value of the cracked light oil fraction is preferably 0.05 mgKOH / g or less, more preferably less than 0.05 mgKOH / g, and even more preferably 0.03 mgKOH / g or less. The smaller the acid value, the more preferable it is, and there is no particular lower limit, and 0.0 mgKOH / g is particularly preferred. If the acid value is within the above range, the normal temperature oil passing performance is improved, and corrosion of components can be suppressed.

[0070] (b 12 ) Pour point The pour point of the cracked light oil fraction is preferably −10.0° C. or lower, more preferably −12.5° C. or lower, and even more preferably −15.0° C. or lower, and although there is no particular lower limit, it is usually −35.0° C. or higher. If the pour point is within the above range, the fluidity in storage tanks and piping at low temperatures is improved, and the handleability is also improved.

[0071] (b 13 )Nitrogen content The nitrogen content of the cracked light oil fraction is preferably 500 ppm by mass or less, more preferably 400 ppm by mass or less, and even more preferably 300 ppm by mass or less, and although there is no particular lower limit, it is usually 50 ppm by mass or more. If the nitrogen content is within the above range, NOx emissions can be reduced, thereby improving environmental performance.

[0072] (b 14 ) Distillation properties As the distillation properties of the cracked light oil fraction, the 10% by volume distillation temperature is preferably 170.0 ° C. or more, more preferably 180.0 ° C. or more, and even more preferably 195.0 ° C. or more, with the upper limit being preferably 230.0 ° C. or less, more preferably 220.0 ° C. or less, and even more preferably 210.0 ° C. or less. The 50% by volume distillation temperature is preferably 240.0 ° C. or more, more preferably 250.0 ° C. or more, and even more preferably 260.0 ° C. or more, with the upper limit being preferably 300.0 ° C. or less, more preferably 285.0 ° C. or less, and even more preferably 270.0 ° C. or less. The 90% by volume distillation temperature is preferably 310.0 ° C. or more, more preferably 320.0 ° C. or more, and even more preferably 330.0 ° C. or more, with the upper limit being preferably 370.0 ° C. or less, more preferably 355.0 ° C. or less, and even more preferably 340.0 ° C. or less. When the distillation properties of the cracked light oil fraction are the above 10% by volume distillation temperature, 50% by volume distillation temperature and 90% by volume distillation temperature, the effects of low boiling point components and high boiling point components are suppressed and combustion performance is improved. In this specification, the 10% by volume distillation temperature, 50% by volume distillation temperature, and 90% by volume distillation temperature are values ​​measured in accordance with JIS K2254:2018 (Petroleum products - Determination of distillation properties - (normal pressure method)).

[0073] (Content of light cracked oil fraction) The content of the cracked light oil fraction based on the total amount of the composition is 20.0% by volume or more and 40.0% by volume or less. If the content of the cracked light oil fraction is less than 20.0% by volume, room temperature oil passing performance decreases, and if it exceeds 40.0% by volume, combustion performance decreases. From the viewpoint of improving the combustion performance and room temperature oil passing performance, the content of the cracked light oil fraction based on the total amount of the composition is preferably 22.5% by volume or more, and the upper limit is preferably 37.5% by volume or less.

[0074] (Other diesel and kerosene fractions) The fuel oil composition of this embodiment may contain, in addition to the above-mentioned cracked light oil fraction, light oil fractions such as straight-run light oil fraction, vacuum light oil fraction, desulfurized light oil fraction, desulfurized cracked light oil fraction, and kerosene fractions such as straight-run kerosene fraction, desulfurized kerosene fraction, etc. Among these light oil fractions and kerosene fractions, straight-run light oil fractions are preferred from the viewpoint of improving combustion performance and normal temperature oil passing performance by combining with fatty acid alkyl esters and cracked light oil fractions. Directly desulfurized diesel fraction (diesel fraction obtained by directly desulfurizing atmospheric distillation residue and / or vacuum distillation residue in a desulfurization unit) · Straight-run diesel fraction (diesel fraction obtained by distilling crude oil at atmospheric pressure using an atmospheric distillation unit) Vacuum diesel fraction (diesel fraction obtained by vacuum distillation of atmospheric distillation residue using a vacuum distillation unit) Desulfurized diesel fraction (diesel fraction obtained by desulfurizing straight-run diesel fraction and / or vacuum diesel fraction) Desulfurized cracked diesel fraction (a diesel fraction obtained by desulfurizing catalytic cracking diesel fraction obtained by fluid catalytic cracking of atmospheric distillation residue and / or vacuum distillation residue) Straight-run kerosene fraction (kerosene fraction obtained by distilling crude oil at atmospheric pressure using an atmospheric distillation unit) Desulfurized kerosene fraction (kerosene fraction obtained by desulfurizing straight-run kerosene fraction)

[0075] (Properties of other diesel fractions) The other diesel fractions that can be used in the present embodiment preferably have the following properties. When the other diesel fractions have the following properties, excellent combustion performance and room temperature oil passing performance are easily obtained. The kinematic viscosity at 50°C is preferably 2.900 mm 2 / s or more, more preferably 4.000mm 2 / s or more, with the upper limit preferably being 5,000 mm 2 / s or less, more preferably 4.400 mm 2 / s or less. The sulfur content is preferably 0.40% by mass or less, more preferably 0.10% by mass or less, and the lower limit is preferably as low as possible, and is usually 0.01% by mass. The aromatic content is preferably 40.0% by volume or more, more preferably 42.0% by volume or less, and there is no particular upper limit, but it is usually 65.0% by volume or less. The content of aromatic components having 3 or more rings is preferably 2.0% by volume or more, more preferably 2.3% by volume or more, and there is no particular upper limit, but it is usually 5.0% by volume or less. The density at 15°C is preferably 0.8300 g / cm 3 More preferably, 0.8400 g / cm 3 The upper limit is preferably 0.8900 g / cm 3 Less than or equal to 0.8800 g / cm 3 The following is the result. The flash point is preferably 60.0°C or higher, more preferably 65.0°C or higher. The residual carbon content of the 10% residual oil is preferably 0.01% by mass or more, and the upper limit is preferably 0.20% by mass or less. The cetane number is preferably 30.0 or more, more preferably 35.0 or more, and there is no particular upper limit, but it is usually 70.0 or less. The moisture content is preferably 0.10% by volume or less, more preferably less than 0.10% by volume, and even more preferably 0.05% by volume or less. Copper plate corrosion is preferably classified as 1 or lower (1a or 1b) in the assessment of copper plate, and more preferably 1a. The acid value is preferably 0.05 mgKOH / g or less, more preferably less than 0.05 mgKOH / g, and even more preferably 0.03 mgKOH / g or less. The smaller the acid value, the more preferable it is, and there is no particular lower limit, and the most preferable is 0.0 mgKOH / g. The pour point is preferably −0.0° C. or less, more preferably −2.5° C. or less. The nitrogen content is preferably 500 ppm by mass or less, more preferably 400 ppm by mass or less, and further preferably 300 ppm by mass or less, and although there is no particular lower limit, it is usually 50 ppm by mass or more. As for the distillation properties, the 10% by volume distillation temperature is preferably 170.0° C. or higher, more preferably 180.0° C. or higher, with the upper limit being preferably 270.0° C. or lower, more preferably 260.0° C. or lower. The 50% by volume distillation temperature is preferably 250.0° C. or higher, more preferably 265.0° C. or higher, with the upper limit being preferably 310.0° C. or lower, more preferably 300.0° C. or lower. The 90% by volume distillation temperature is preferably 310.0° C. or higher, more preferably 330.0° C. or higher, with the upper limit being preferably 370.0° C. or lower, more preferably 355.0° C. or lower.

[0076] (Other heavy oil fractions) The fuel oil composition of the present embodiment may also contain atmospheric distillation residual oil, vacuum distillation residual oil, direct decomposition heavy oil fraction, and cracked heavy oil. Among these heavy oil fractions, atmospheric distillation residual oil is preferred from the viewpoint of improving combustion performance and room temperature oil passing performance by combining with fatty acid alkyl esters and cracked light oil fractions. Atmospheric distillation residual oil (residual oil obtained by atmospheric distillation of crude oil using an atmospheric distillation unit) · Vacuum distillation residual oil (residual oil obtained by vacuum distillation of atmospheric distillation residual oil using a vacuum distillation apparatus) Directly desulfurized heavy oil fraction (heavy oil fraction obtained by directly desulfurizing atmospheric distillation residue and / or vacuum distillation residue in a desulfurization unit) Cracked heavy oil fraction (heavy oil fraction obtained by fluid catalytic cracking of directly decomposed heavy oil fraction)

[0077] (Properties of other heavy oil fractions) The other heavy oil fractions that can be used in the present embodiment preferably have the following properties. When the other heavy oil fractions have the following properties, excellent combustion performance and room temperature oil passing performance are easily obtained. The kinematic viscosity at 50°C is preferably 190.0 mm 2 / s or less, preferably 185.0 mm 2 / s or less, and there is no particular lower limit, usually 30.00 mm 2 / s or more. The sulfur content is preferably 3.0% by mass or less, more preferably 2.75% by mass or less, and there is no particular lower limit, but it is usually 0.50% by mass or more. The density at 15°C is preferably 0.8800 g / cm 3 More preferably, 0.9000g / cm 3 The upper limit is preferably 0.9700 g / cm 3 Less than or equal to 0.9600 g / cm 3 The following is the result. The carbon residue is preferably 12.0% by mass or less, more preferably 9.0% by mass or less, and even more preferably 7.5% by mass or less, with the lower limit being preferably 3.0% by mass or more, and more preferably 5.0% by mass or more. In this specification, the carbon residue is a value measured in accordance with JIS K 2270-2:2009 (Crude oil and petroleum products-Determination of carbon residue-Part 2: Micro method).

[0078] (Various additives) In the fuel oil composition of this embodiment, various additives such as antioxidants, low-temperature fluidity improvers, lubricity improvers, cetane number improvers, combustion promoters, detergents, sludge dispersants, and fungicides can be appropriately selected and blended as necessary within the range that allows the above-mentioned various properties to be maintained. In addition, coumarin may be blended from the viewpoint of diesel delivery tax.

[0079] (Application) The fuel oil composition of the present embodiment can be used in both internal combustion engines and external combustion engines, but considering the excellent combustion performance and room temperature oil passing performance, it is preferable to use it in an internal combustion engine. In addition, considering the above-mentioned properties of the fuel oil composition of the present embodiment, it is particularly suitable for use in internal combustion engines such as marine diesel engines.

[0080] [Method for producing fuel oil composition] The fuel oil composition of this embodiment can be produced by mixing the above-mentioned fatty acid alkyl ester and cracked light oil fraction, and, if necessary, other light oil fractions, kerosene fractions, heavy oil fractions, and various additives, so that the contents of the fatty acid alkyl ester and cracked light oil fraction based on the total volume of the composition are 15.0 vol.% or more and 35.0 vol.% or less, and 20.0 vol.% or more and 40.0 vol.% or less, respectively.

[0081] There is no particular restriction on the order of mixing the fatty acid alkyl ester, the cracked light oil fraction, and, if necessary, other light oil fractions, kerosene fractions, and heavy oil fractions, and various additives. For example, the fatty acid alkyl ester may be mixed by sequentially adding the cracked light oil fraction, the other light oil fractions, the heavy oil fractions, and various additives to the fatty acid alkyl ester; the fatty acid alkyl ester, the cracked light oil fraction, and, if necessary, the other light oil fractions, kerosene fractions, and heavy oil fractions, and various additives may be mixed simultaneously (lump-blending); or the fatty acid alkyl ester and the cracked light oil fraction may be mixed in advance, and then the other light oil fractions, kerosene fractions, and heavy oil fractions, and various additives may be mixed therewith if necessary. EXAMPLES

[0082] The present invention will now be described in more detail with reference to the following examples, but the present invention is not limited to these examples. The properties of each substrate were determined according to the following methods, as described above.

[0083] [Measurement of properties and composition] The properties and compositions of the various base materials, i.e., fatty acid alkyl esters, cracked light oil fraction, direct desulfurized light oil fraction, direct desulfurized light oil fraction, and atmospheric distillation residual oil, used in the Examples and Comparative Examples, and the properties and compositions of the fuel oil compositions in the Examples and Comparative Examples, were measured by the following methods. The properties and compositions of the fatty acid alkyl esters are shown in Table 1, and the properties and compositions of the other various base materials are shown in Table 2. The properties and compositions of the fuel oil compositions are shown in Table 3. (1)(a4)(b5) Density at 15°C: Measured in accordance with JIS K 2249-1:2011 (Crude oil and petroleum products-Determination of density-Part 1: Vibration method). (2)(a5)(b1) Kinematic viscosity at 50°C: Measured in accordance with JIS K 2283:2000 (Testing method for kinematic viscosity of crude oil and petroleum products). (3)(a6)(b2) Sulfur content: The sulfur content of the fuel oil composition, the cracked diesel fraction, the directly desulfurized diesel fraction, the directly desulfurized diesel fraction and the atmospheric residue is determined in accordance with JIS K 2541-4:2003 (Crude petroleum and petroleum products-Determination of sulfur content-Part 4: Radioactive excitation method), and the sulfur content of the fatty acid alkyl ester is determined in accordance with JIS K 2541-6:2013 (Crude petroleum and petroleum products-Determination of sulfur content-Part 6: Ultraviolet fluorescence method). (4)(b3)(b4) Aromatic content (1-ring aromatics, 2-ring aromatics and 3-ring aromatics), saturates and olefins content: These were measured by the High Performance Liquid Chromatography method as specified in JPI-5S-49-2007, Petroleum Products - Hydrocarbon Type Testing Method. (5)(a3)(b7) Carbon residue of 10% residual oil: This value is determined in accordance with JIS K 2270-2:2009 (Crude petroleum and petroleum products-Determination of carbon residue-Part 2:Micro method) using 10% residual oil prepared in accordance with Appendix A. (6)(a7)(b6) Flash point: The flash points of the fuel oil composition, the cracked light oil fraction, the directly desulfurized light oil fraction, the directly run light oil fraction and the atmospheric distillation residue were measured in accordance with JIS K 2265-3:2007 (Crude petroleum and petroleum products-Flash point test method-Part 3: Pensky-Martens closed-close method), and the flash points of the fatty acid alkyl esters were measured in accordance with JIS K 2265-2:2007 (Crude petroleum and petroleum products-Flash point test method-Part 2: Rapid equilibrium closed-close method). (7)(a1)(b8) Cetane number: A value measured in accordance with JIS K 2280-4:2013 (Petroleum products -- Determination of octane number, cetane number and cetane index -- Part 4: Cetane number). (8)(a8)(b9) Moisture content: The moisture content of the fuel oil composition, the cracked diesel fraction, the directly decomposed diesel fraction, the directly run diesel fraction and the atmospheric distillation residue was measured in accordance with JIS K 2275-1:2015 (Crude oil and petroleum products-Determination of water content-Part 1: Distillation method), and the moisture content of the fatty acid alkyl ester was measured in accordance with JIS K 2275-3:2015 (Crude oil and petroleum products-Determination of water content-Part 3: Karl Fischer coulometric titration method). (9)(a9)(b 10 ) Copper plate corrosion: Measured according to JIS K 2513:2000 (Petroleum products - Copper plate corrosion test method). The test temperature was 50°C and the test time was 3 hours. (10)(a2)(b 11 ) Acid value: Measured in accordance with JIS K 2501:2003 (Petroleum products and lubricants - Neutralization number test method). (11)(a 10 )(b 12 ) Pour point: Measured in accordance with JIS K2269:1987 (Test method for pour point and cloud point of crude oil and petroleum products). (12)(b 13 ) Nitrogen content: Measured in accordance with JIS K 2609:1998 (Crude oil and petroleum products - Determination method for nitrogen content). (a 11 ) Composition analysis of fatty acid alkyl esters: Measured by gas chromatography analysis using a flame ionization detector (FID) in accordance with "2.4.21.3-77 Fatty acid composition (FID temperature-programmed gas chromatography method)" in the Standard Methods for Analysis of Fats, Oils and Related Materials (established by the Japan Oil Chemists' Society in 1993). ·(b 14 ) Distillation properties (10% by volume distillation temperature, 50% by volume distillation temperature, and 90% by volume distillation temperature): Measured in accordance with JIS K2254:2018 (Petroleum products - Determination of distillation properties - (normal pressure method)).

[0084] [Performance evaluation criteria] The following performances were evaluated according to 1 to 4, and the worst evaluation was used as the overall evaluation. Evaluation of each performance is shown in Table 3.

[0085] 1. Combustion performance The increase (Δ cetane number) of the cetane numbers of the fuel oil compositions of the Examples and Comparative Examples relative to the cetane number of the Reference Example was evaluated according to the following criteria. A: The increase in cetane number (Δ cetane number) is 2.5 or more. B: Increase in cetane number (Δ cetane number) is 2.0 or more and less than 2.5 C: The increase in cetane number (Δ cetane number) is less than 2.0

[0086] 2.Normal temperature oil passing performance An 18 L can (made of tinplate) was provided with an open part (φ32.5 mm) at the top to allow air circulation, and 3 L of the fuel oil composition of the Examples and Comparative Examples was placed in the container and stored for 90 days in a dark place at room temperature (no temperature control was performed by air conditioning, and the room temperature during the period was 16.0 to 28.0°C). After storage, the fuel oil composition was subjected to an oil permeability test using an oil permeability tester described in JP 2007-197512 A. The amount of oil passing through the fuel oil composition for 10 minutes was evaluated according to the following criteria. A: The amount of oil passing through is 1.10L or more. B: The amount of oil passing is 0.70L or more and less than 1.10L C: The amount of oil passing through is less than 0.70L

[0087] 3.Low temperature flow performance The pour points of the examples and comparative examples were evaluated according to the following criteria. A: Pour point is -2.5℃ or less B: Pour point is greater than -2.5℃ and less than 5.0℃ C: Pour point is over 5.0℃

[0088] 4.Environmental performance The sulfur content was evaluated according to the following criteria. A: Sulfur content is 0.300% by mass or less B: Sulfur content is more than 0.300 mass% and 0.400 mass% or less C: Sulfur content exceeds 0.400% by mass

[0089] [Examples 1 to 3, Comparative Examples 1 to 7 and Reference Example] Various base materials having the properties and compositions shown in Tables 1 and 2 were mixed in the ratios shown in Table 3 to prepare the fuel oil compositions of Examples 1 to 3, Comparative Examples 1 to 7 and Reference Example. The resulting fuel oil compositions were evaluated for combustion performance, room temperature oil passing performance, low temperature flow performance and environmental performance according to the methods described above. The results are shown in Table 3.

[0090] [Table 1] *1. Base material 1 (fatty acid alkyl ester 1) and base material 2 (fatty acid alkyl ester 2) are both fatty acid methyl esters obtained using waste edible oil, including rapeseed oil.

[0091] [Table 2]

[0092] [Table 3]

[0093] [Performance evaluation results] As shown in Table 3, the fuel oil composition of this embodiment was evaluated to be good in terms of combustion performance, room temperature oil passing performance, low temperature flow performance and environmental performance, and it was confirmed that it can withstand use in internal combustion engines such as marine diesel engines. On the other hand, the fuel oil composition of Comparative Example 1, which contains specific fatty acid alkyl ester 1 but has a low content, is inferior in combustion performance, while the fuel oil composition of Comparative Example 2, which contains a high content, is inferior in room temperature oil passing performance. It was confirmed that the fuel oil compositions of Comparative Examples 5 to 7, which do not contain specific fatty acid alkyl ester 1 and contain fatty acid alkyl ester 2 with a low residual carbon content in 10% residual oil, all have inferior room temperature oil passing performance. It was also confirmed that the fuel oil composition of Comparative Example 3, which contains a low content of cracked light oil fraction, is inferior in room temperature oil passing performance, while the fuel oil composition of Comparative Example 4, which contains a high content, is inferior in combustion performance. [Industrial Applicability]

[0094] The fuel oil composition of the present embodiment contains a fatty acid alkyl ester, and thus has excellent combustion performance, room temperature oil passing performance, and also has excellent low-temperature flow performance and environmental performance. It is suitable for use in internal combustion engines and external combustion engines, and is particularly suitable for use in internal combustion engines such as marine diesel engines.

Claims

1. The following (a １ ) to (a ３ ) and the following (b １ ) to (b ４ and a cracked light oil fraction satisfying all of the following conditions (1) to (5): the fatty acid alkyl ester is an ester of a fatty acid having from 8 to 22 carbon atoms and an alkyl alcohol having from 1 to 4 carbon atoms, the content of the fatty acid alkyl ester is from 15.0 to 35.0 vol% based on the total volume of the composition, and the content of the cracked light oil fraction is from 20.0 to 40.0 vol% based on the total volume of the composition, (a １ ) Cetane number is 49.0 or higher (a ２ ) Acid value is 0.50 mg KOH / g or less (a ３ ) The residual carbon content of 10% residual oil is 0.80% by mass or more and 1.50% by mass or less (b １ ) Kinematic viscosity at 50 ° C. is 1.700 mm ２ / s or more 3.600mm ２ / s or less (b) ２ ) Sulfur content is less than 0.40% by mass (b ３ ) Aromatic content is 50.0% by volume or more (b ４ ) Aromatic content of 3 or more rings is 5.0% by volume or more (1) Density at 15°C is 0.8700 g / cm ３ 0.8900g / cm or more ３ below (2) Kinematic viscosity at 50 ° C. is 2.000 mm ２ / s or more 4.500mm ２ / s or less (3) Sulfur content is 0.400% by mass or less (4) Aromatic content of 3 or more rings is 2.9% by volume or more (5) The residual carbon content of 10% residual oil is 0.21% by mass or more and 0.60% by mass or less.

2. 2. The fuel oil composition according to claim 1, wherein the fatty acid alkyl ester is a fatty acid methyl ester.

3. 3. The fuel oil composition according to claim 1, wherein the fatty acid is a mixed fatty acid containing two or more fatty acids each having from 8 to 22 carbon atoms.

4. 4. The fuel oil composition according to claim 3, wherein the mixed fatty acid is obtained from at least one raw material selected from animal oils and vegetable oils.

5. 5. The fuel oil composition according to claim 4, wherein the raw material is waste cooking oil.

6. 3. The fuel oil composition according to claim 1, which is used in an internal combustion engine.

7. It is an ester of a fatty acid having 8 to 22 carbon atoms and an alkyl alcohol having 1 to 4 carbon atoms, １ ) to (a ３ ) and the following (b １ ) to (b ４ and a cracked light oil fraction that satisfies all of the following conditions (1) to (5): (a １ ) Cetane number is 49.0 or higher (a ２ ) Acid value is 0.50 mg KOH / g or less (a ３ ) The residual carbon content of 10% residual oil is 0.80% by mass or more and 1.50% by mass or less (b １ ) Kinematic viscosity at 50 ° C. is 1.700 mm ２ / s or more 3.600mm ２ / s or less (b) ２ ) Sulfur content is less than 0.40% by mass (b ３ ) Aromatic content is 50.0% by volume or more (b ４ ) Aromatic content of 3 or more rings is 5.0% by volume or more (1) Density at 15°C is 0.8700 g / cm ３ 0.8900g / cm or more ３ below (2) Kinematic viscosity at 50 ° C. is 2.000 mm ２ / s or more 4.500mm ２ / s or less (3) Sulfur content is 0.400% by mass or less (4) Aromatic content of 3 or more rings is 2.9% by volume or more (5) The residual carbon content of 10% residual oil is 0.21% by mass or more and 0.60% by mass or less.