JP2008231201A - A-type heavy oil composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an A-type heavy oil composition excellent in combusibility of an off road engine, having small influence to a member, and having excellent performance in low temperature fluidity. <P>SOLUTION: In the A-type heavy oil composition fulfilling JIS No. 1 heavy oil specification, a specific aliphatic acid alkyl ester is formulated, at a predetermined ratio, in a hydrotreating oil having a sulfur content of 800 mass ppm or lower, a monocyclic naphthene content of 10 vol.% or higher, a monocyclic aromatic content of 20 vol.% or lower, a 90% distillation temperature of 280-350°C, and a difference of 80% distillation temperature and 20% distillation temperature of 50-150°C. The A-type heavy oil composition is characterized in that volume modulus is 1,350-1,550 MPa and the whole insoluble amount after the oxidation stability test is 2.0 mg/100 ml or less. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an A heavy oil composition having a low sulfur content and containing a fatty acid alkyl ester. More specifically, the present invention relates to an A heavy oil composition having excellent combustibility of an off-road engine, little influence on members, and excellent low-temperature fluidity.

Conventionally, as the base material for heavy oil A, straight-run kerosene obtained from crude oil atmospheric distillation equipment, straight-run gas oil obtained from crude oil atmospheric distillation equipment, hydrorefining treatment or hydrodesulfurization treatment, Those subjected to hydrorefining treatment or hydrodesulfurization treatment are known. Conventional A heavy oil compositions are produced by blending one or more of the above light oil base and kerosene base. In addition, it is produced by applying one or more kinds of atmospheric residual oil, direct desorption residual oil, reduced pressure residual oil, etc. as residual carbon base materials. Moreover, additives such as a cetane number improver and a low temperature fluidity improver are blended with these A heavy oil compositions as necessary (see, for example, Non-Patent Document 1).
Seiichi Konishi, “Introduction to Fuel Engineering”, Saika Hanafusa, March 1991, p. 136-144

  By the way, in recent years, with the aim of urgently improving the air environment and reducing the environmental load, there has been a demand for a reduction in the sulfur content and aromatic content in heavy fuel oil A, which is also a fuel for internal combustion engines. At the same time, in order to cope with the global warming problem, there is a need for fuel properties that contribute to further improving fuel efficiency and reduce carbon dioxide. One of the solutions is biofuels such as synthetic fuels and renewable energy. The use of fuel (hereinafter also referred to as BDF) as an alternative fuel is being studied.

The conventional A heavy oil base contains an aromatic content of about 50% by volume at maximum, and about 25% by average on average. In addition, the A heavy oil fraction contains several percent of polycyclic aromatic components having two or more rings, which are considered to have a large ability to generate particulate matter (hereinafter also referred to as PM). In general, the aromatic content cannot be sufficiently reduced by hydrorefining treatment or hydrodesulfurization treatment, so it is necessary to introduce a dearomatic process, but the existing equipment may not provide the desired A heavy oil base material. In addition, the purification cost increases significantly.
In general, the kerosene base material has a lower aromatic content than the A heavy oil base material (up to about 40% by volume, and on average, about 20% by volume). By mixing with the heavy oil base material, the aromatic content can be reduced. However, the A heavy oil composition simply obtained in this way is low in density and very light, which causes a deterioration in fuel consumption and a decrease in output. Furthermore, since the kinematic viscosity of the composition is reduced by mixing the A heavy oil base material and the kerosene base material, a problem of the lubricating surface of the fuel injection pump or the like is likely to occur.

  Synthetic oils that use natural gas, asphalt, coal, or the like as raw materials have attracted attention as synthetic fuels. These fuel base materials are characterized by containing almost no aromatic content or sulfur content. However, in view of the influence on the members used in the fuel injection system, when such a fuel is used, the rubber member used in the aged equipment is rather contracted, resulting in fuel leakage ( (Leakage) may occur. In addition, since it is a base material mainly composed of paraffin, there is a concern that the precipitation of wax during start-up at low temperatures and the deterioration of fuel consumption due to low density are concerned.

  On the other hand, BDF is mainly a mixture of fatty acid alkyl esters made from vegetable oil, which contains almost no aromatics or sulfur, and is itself an oxygen-containing compound with oxygen in the molecule. It is attracting attention as a promising candidate for fuel. In addition, because it is plant-derived, it is positioned as renewable energy, so the international carbon dioxide reduction protocol signed in 1997, the so-called Kyoto Protocol, does not count carbon dioxide derived from BDF as an emission amount. The BDF also has a policy merit.

  However, depending on the composition of the fatty acid alkyl ester contained, there are those that are solid at room temperature and those that have a very heavy boiling point, so when used simply as a substitute for heavy oil A, flow performance at low temperatures and unburned Deterioration of hydrocarbon emissions and nitrogen oxide emissions will occur. The fatty acid alkyl ester itself is a chemically stable substance, but the fatty acid glyceride, alkyl alcohol, and by-product glycerin mixture, which are raw materials for refining the fatty acid alkyl ester, are used for off-road engine parts and fuel injection systems. The adverse effects of are very concerned. Therefore, when using BDF as a substitute for A heavy oil, it is natural to pay attention to the properties of BDF itself, but in addition to that, BDF can be used by replacing it with A heavy oil in its entirety, or with a high blending ratio with A heavy oil. Mixing is problematic and must be avoided.

  Therefore, regarding the provision of A heavy oil composition that reduces harmful exhaust components, especially particulate matter (PM) and fine particles and nitrogen oxides at the same time, improves fuel consumption, has little effect on members, and has excellent low-temperature fluidity However, these improvements in performance cannot be achieved at the same time by simply using existing refining methods or simply replacing them with alternative fuels. Furthermore, because these off-road engine performance is closely related to other fuel properties, it is very difficult to design a high-quality fuel that can simultaneously achieve these required performances at a high level, and commercial fuels. There are no examples or findings that fully satisfy the various performance requirements for oil and are based on the study of realistic production methods.

  The present invention has been made in view of such a situation, and the object thereof is excellent in the combustibility of an off-road engine when used as an off-road diesel fuel, has little influence on members, and has low temperature fluidity. It is in providing A heavy oil composition which has the outstanding performance.

As a result of intensive studies to solve the above problems, the present inventors have completed the present invention. That is, in the present invention, the sulfur content is 800 mass ppm or less, the monocyclic naphthene content is 10% by volume or more, the monocyclic aromatic content is 20% by volume or less, and the 90% distillation temperature is 280 ° C. or more. A hydrorefined oil having a difference of 350 ° C. or lower and a difference between 80% distillation temperature and 20% distillation temperature of 50 ° C. or higher and 150 ° C. or lower is selected from myristic acid alkyl ester, palmitic acid alkyl ester and stearic acid alkyl ester Any one of fatty acid alkyl esters (B) containing any one or more of fatty acid alkyl esters (A) and selected from lauric acid alkyl esters, oleic acid alkyl esters, linoleic acid alkyl esters and linolenic acid alkyl esters The total of the mass content of the fatty acid alkyl ester (A) The total mass content of (B) is 0.1 or more and 2.0 or less, the average molecular weight as a fatty acid alkyl ester mixture is 500 or less, the total acid value is 1.0 mgKOH / g or less, and the sulfur content is 5 mass. The volume modulus of elasticity is 1350 MPa or more and 1550 MPa or less, and the total insoluble matter after the oxidation stability test is 2.0 mg / 100 mL or less. The present invention relates to an A heavy oil composition that satisfies the JIS heavy oil standard.
RBDF = (− 6 × C × FAME + HDS × (2 × PA + PN)) / 100
0 ≦ RBDF ≦ 10
RBDF: BDF index
C: Sum of mass content of fatty acid alkyl ester (A) / fatty acid alkyl
Sum of mass content of ruester (B) FAME: Fatty acid alkyl ester mixture content (volume%)
HDS: blended hydrorefined oil (volume%)
PA: Aromatic content of 2 or more rings in hydrorefined oil (volume%)
PN: Content of naphthene in two or more rings in hydrorefined oil (volume%)

The A heavy oil composition preferably has a density at 15 ° C. of 800 kg / m ³ or more and 850 kg / m ³ or less, a cetane number of 40 or more, and an HFRR wear scar diameter (WS 1.4) of 410 μm or less.
Moreover, in the said A heavy oil composition, it is preferable to mix | blend the fatty-acid alkylester mixture which used vegetable oil as the raw material, and is a water content of 800 volume ppm or less.

  The A heavy oil composition of the present invention is an A heavy oil composition in which an appropriate amount of the hydrorefined oil having the above specific properties and the fatty acid alkyl ester mixture having the above specific properties are mixed to satisfy the predetermined properties. Therefore, it is excellent in the combustibility of the off-road engine, which is difficult to realize with the conventional A heavy oil composition, has little influence on the member, and has excellent performance in low-temperature flow.

Hereinafter, the present invention will be described in detail.
As a constituent of the A heavy oil composition of the present invention, the sulfur content is 800 mass ppm or less, the monocyclic naphthene content is 10% by volume or more, the monocyclic aromatic content is 20% by volume or less, and 90% retention A hydrorefined oil having a distillation temperature of 280 ° C. or higher and 350 ° C. or lower and a difference between 80% distillation temperature and 20% distillation temperature of 50 ° C. or higher and 150 ° C. or lower is used.

  The hydrorefined oil according to the present invention is a low sulfur gas oil fraction, a kerosene fraction, or a mixture thereof obtained by hydrotreating a predetermined raw material oil.

  Gas oil fraction feedstocks include straight-run gas oil obtained from crude oil atmospheric distillation equipment, straight-run heavy oil obtained from atmospheric distillation equipment, and vacuum gas oil obtained by treating residual oil with vacuum distillation equipment , Catalytic cracked light oil or hydrocracked diesel oil obtained by catalytic cracking or hydrocracking heavy vacuum oil or desulfurized heavy oil, hydrorefined diesel oil obtained by hydrorefining these petroleum hydrocarbons or hydrodesulfurization A light oil etc. are mentioned.

The hydrorefining of the petroleum hydrocarbon can be performed using a hydrodesulfurization apparatus common in petroleum refining. In general, the reaction is performed under the conditions of a reaction temperature of 300 to 380 ° C., a hydrogen pressure of 3 to 8 MPa, LHSV 0.3 to 2 h ⁻¹ , and a hydrogen / oil ratio of 100 to 500 NL / L.
As a catalyst used for hydrorefining, a general hydrodesulfurization catalyst can be applied. As the active metal, normally, Group 6A and Group 8 metals of the periodic table are preferably used, and examples thereof include Co—Mo, Ni—Mo, Co—W, and Ni—W. As the carrier, a porous inorganic oxide mainly composed of alumina is used.

Moreover, as a hydrorefined oil concerning this invention, the hydrorefined light oil fraction obtained by hydrotreating the above-mentioned raw material oil in presence of a hydrogenation catalyst can be used. The hydrotreating conditions are a reaction temperature of 170 to 320 ° C., a hydrogen pressure of 2 to 10 MPa, LHSV of 0.1 to 2 h ⁻¹ , and a hydrogen / oil ratio of 100 to 800 NL / L. The reaction temperature is preferably 175 ° C to 300 ° C, the hydrogen pressure is 2.5 to 8 MPa, the LHSV is 0.2 to 1.5 h ^-1 , and the hydrogen / oil ratio is 150 to 600 NL / L, more preferably the reaction temperature is 180 ° C to 280 ° C. The hydrogen pressure is 3 to 7 MPa, the LHSV is 0.3 to 1.2 h ⁻¹ , and the hydrogen / oil ratio is 150 to 500 NL / L. The lower the reaction temperature, the more advantageous for the hydrogenation reaction, but not for the desulfurization reaction. The higher the hydrogen pressure and the hydrogen / oil ratio, the more the desulfurization and hydrogenation reactions are promoted, but there is an optimal point economically. The lower the LHSV, the better the reaction, but if it is too low, it is disadvantageous because it requires an extremely large reaction column volume and excessive capital investment.

The apparatus for hydrotreating the feedstock may be of any configuration, the reaction towers may be used alone or in combination, and hydrogen may be additionally injected between the reaction towers, gas-liquid separation operation or hydrogen sulfide. You may have the removal equipment.
A fixed bed system is preferably employed as the reaction mode of the hydrotreating apparatus. Hydrogen can take either a countercurrent or cocurrent flow with respect to the feedstock, and may have a plurality of reaction towers and a combination of countercurrent and cocurrent. As a general format, it is a down flow, and a gas-liquid twin parallel flow format is preferable. Hydrogen gas may be injected into the middle stage of the reaction tower as a quench for the purpose of removing reaction heat or increasing the hydrogen partial pressure.

  The catalyst used for the hydrotreatment is a catalyst in which a hydrogenation active metal is supported on a porous carrier. An inorganic oxide is mentioned as a porous support | carrier. Specific inorganic oxides include alumina, titania, zirconia, boria, silica, or zeolite. In the present invention, at least one of titania, zirconia, boria, silica, and zeolite is composed of alumina. Things are good. The production method is not particularly limited, but any preparation method can be employed using raw materials in various sols, salt compounds, and the like corresponding to each element. Furthermore, once the composite hydroxide or composite oxide such as silica alumina, silica zirconia, alumina titania, silica titania, and alumina boria is prepared, the preparation process in the state of alumina gel and other hydroxides or in an appropriate solution state It may be prepared by adding at any step. The ratio of alumina to other oxides can be any ratio with respect to the porous carrier, but preferably alumina is 90% by mass or less, more preferably 60% by mass or less, and more preferably 40% by mass or less. .

  Zeolite is a crystalline aluminosilicate, such as faujasite, pentasil, mordenite, etc., which is ultra-stabilized by a predetermined hydrothermal treatment and / or acid treatment, or one whose alumina content in the zeolite is adjusted is used. be able to. Preferably, faujasite and mordenite, particularly preferably Y type and beta type are used. The Y-type is preferably ultra-stabilized, and the ultra-stabilized zeolite by hydrothermal treatment forms new pores in the range of 20 to 100% in addition to the original pore structure called micropores of 20 cm or less. . Known conditions can be used for the hydrothermal treatment conditions.

  The active metal of the catalyst used for the hydrotreatment is at least one metal selected from Group 6A metals of the periodic table. Preferably, it is at least one selected from Mo and W. The active metal may be a combination of a Group 6A metal and a Group 8 metal, specifically, a combination of Mo or W and Co or Ni. For example, Co—Mo, Co—W, Ni—Mo, Combinations such as Ni-W, Co-Ni-Mo, and Co-Ni-W can be employed. As the metal source, a general inorganic salt or a complex salt compound can be used, and as a supporting method, any method of a supporting method used in an ordinary hydrogenation catalyst such as an impregnation method or an ion exchange method can be used. When a plurality of metals are supported, they may be supported simultaneously using a mixed solution, or may be sequentially supported using a single solution. The metal solution may be an aqueous solution or an organic solvent.

The metal support may be performed after the completion of the entire process of preparing the porous support, or after further supporting on the appropriate oxide, composite oxide, zeolite in the intermediate process of preparing the porous support, or after further gel preparation process or Heat concentration and kneading may be performed.
The amount of the active metal supported is not particularly limited, but is 0.1 to 10% by mass, preferably 0.15 to 5% by mass, and more preferably 0.2 to 3% by mass with respect to the catalyst mass.
The catalyst is preferably used after a preliminary reduction treatment in a hydrogen stream. In general, when a gas containing hydrogen is circulated and heat of 200 ° C. or higher is applied according to a predetermined procedure, the active metal on the catalyst is reduced, and hydrogenation activity is exhibited.

As the hydrorefined oil according to the present invention, in addition to the hydrorefined oil of the light oil fraction described above, unrefined oil and / or hydrorefined oil is used as a raw material oil, and the reaction temperature is 220 in the presence of a hydrogenation catalyst. ~ 350 ° C, hydrogen pressure 1-6 MPa, LHSV 0.1-10 h ^-1 , sulfur content obtained by hydrotreating with hydrogen / oil ratio 10-300 NL / L, 8 mass ppm or less, total aromatic content Low volume kerosene fraction (hydrorefined oil kerosene fraction) having an amount of 20 vol% or less, aromatic content of two or more rings of 1 vol% or less, naphthene content of 10 vol% or more, and boiling point range of 140-300 ° C Min).

  Such a low sulfur kerosene fraction is a kerosene fraction obtained by hydrotreating a predetermined feedstock. The raw oil is mainly straight-run kerosene obtained by atmospheric distillation of crude oil, but hydrocracked kerosene produced together with hydrocracked light oil and hydrogen obtained by hydrotreating the above kerosene fraction. Examples include chemical kerosene, natural gas, asphalt, and synthetic kerosene made from coal.

The feedstock oil as the hydrorefined oil kerosene fraction is obtained by hydrorefining a petroleum hydrocarbon using a general hydrodesulfurization apparatus in petroleum refining. Usually, the reaction temperature is 220 to 350 ° C., the hydrogen pressure is ^{1 to} 6 MPa, the LHSV is 0.1 to 10 h ⁻¹ , and the hydrogen / oil ratio is 10 to 300 NL / L.
A general hydrodesulfurization catalyst can be applied as the catalyst. As the active metal, Group 6A and Group 8 metals of the periodic table are usually used, and examples thereof include Co—Mo, Ni—Mo, Co—W, and Ni—W. As the carrier, a porous inorganic oxide mainly composed of alumina is used.

As the hydrorefined oil kerosene fraction according to the present invention, one obtained by hydrotreating (desulfurizing and refining) the above-described raw material oil in the presence of a hydrogenation catalyst can be used.
The hydrotreating conditions are a reaction temperature of 220 to 350 ° C., a hydrogen pressure of ^{1 to} 6 MPa, an LHSV of 0.1 to 10 h ⁻¹ , and a hydrogen / oil ratio of 10 to 300 NL / L. Preferably, the reaction temperature is 250 ° C. to 340 ° C., the hydrogen pressure is 2 to 5 MPa, the LHSV is ^{1 to} 10 h ⁻¹ , and the hydrogen / oil ratio is 30 to 200 NL / L, more preferably the reactivity is 270 ° C. to 330 ° C., the hydrogen pressure is 2 to 4 MPa. , LHSV 2 to 10 h ⁻¹ , hydrogen / oil ratio 50 to 200 NL / L. The lower the reaction temperature, the more advantageous for the hydrogenation reaction, but not for the desulfurization reaction. The higher the hydrogen pressure and the hydrogen / oil ratio, the more the desulfurization and hydrogenation reactions are promoted, but there is an optimal point economically. The lower the LHSV, the more advantageous for the reaction. However, if the LHSV is too low, a very large reaction tower volume is required, resulting in an excessive capital investment.

The apparatus for hydrotreating the feedstock may be of any configuration, the reaction towers may be used alone or in combination, and hydrogen may be additionally injected between the reaction towers, gas-liquid separation operation or hydrogen sulfide. You may have the removal equipment.
A fixed bed system is preferably employed as the reaction mode of the hydrotreating apparatus. Hydrogen can take either a countercurrent or cocurrent flow with respect to the feedstock, and may have a plurality of reaction towers and a combination of countercurrent and cocurrent. A general format is a down flow, and a gas-liquid twin-cocurrent format is preferable. Hydrogen gas may be injected into the middle stage of the reaction tower as a quench for the purpose of removing reaction heat or increasing the hydrogen partial pressure.

  The catalyst used for the hydrotreatment is a catalyst in which a hydrogenation active metal is supported on a porous carrier. An inorganic oxide is mentioned as a porous support | carrier. Specific inorganic oxides include alumina, titania, zirconia, boria, silica, or zeolite. In the present invention, at least one of titania, zirconia, boria, silica, and zeolite is composed of alumina. Things are good. The production method is not particularly limited, but any preparation method can be employed using raw materials in various sols, salt compounds, and the like corresponding to each element. Furthermore, once the composite hydroxide or composite oxide such as silica alumina, silica zirconia, alumina titania, silica titania, and alumina boria is prepared, the preparation process in the state of alumina gel and other hydroxides or in an appropriate solution state It may be prepared by adding at any step. The ratio of alumina to other oxides can be any ratio with respect to the porous carrier, but preferably alumina is 90% by mass or less, more preferably 60% by mass or less, and more preferably 40% by mass or less. .

  Zeolite is a crystalline aluminosilicate, such as faujasite, pentasil, mordenite, etc., which is ultra-stabilized by a predetermined hydrothermal treatment and / or acid treatment, or one whose alumina content in the zeolite is adjusted is used. be able to. Preferably, faujasite and mordenite, particularly preferably Y type and beta type are used. The Y-type is preferably ultra-stabilized, and the ultra-stabilized zeolite by hydrothermal treatment forms new pores in the range of 20 to 100% in addition to the original pore structure called micropores of 20 cm or less. . Known conditions can be used for the hydrothermal treatment conditions.

  The active metal of the catalyst used for the hydrotreatment is at least one metal selected from Group 6A metals of the periodic table. Preferably, it is at least one selected from Mo and W. The active metal may be a combination of a Group 6A metal and a Group 8 metal, specifically, a combination of Mo or W and Co or Ni. For example, Co—Mo, Co—W, Ni—Mo, Combinations such as Ni-W, Co-Ni-Mo, and Co-Ni-W can be employed. As the metal source, a general inorganic salt or a complex salt compound can be used, and as a supporting method, any method of a supporting method used in an ordinary hydrogenation catalyst such as an impregnation method or an ion exchange method can be used. When a plurality of metals are supported, they may be supported simultaneously using a mixed solution, or may be sequentially supported using a single solution. The metal solution may be an aqueous solution or an organic solvent.

The metal support may be performed after the completion of the entire process of preparing the porous support, or after further supporting on the appropriate oxide, composite oxide, zeolite in the intermediate process of preparing the porous support, or after further gel preparation process or Heat concentration and kneading may be performed.
The amount of the active metal supported is not particularly limited, but is 0.1 to 10% by mass, preferably 0.15 to 5% by mass, and more preferably 0.2 to 3% by mass with respect to the catalyst mass.
The catalyst is preferably used after a preliminary reduction treatment in a hydrogen stream. In general, when a gas containing hydrogen is circulated and heat of 200 ° C. or higher is applied according to a predetermined procedure, the active metal on the catalyst is reduced, and hydrogenation activity is exhibited.

  The hydrorefined oil according to the present invention needs to satisfy predetermined properties by using at least one of the above-described light oil fraction and kerosene fraction. Moreover, the hydrorefined oil in this invention can be comprised by mix | blending a some light oil fraction base material and a kerosene fraction base material in the category which satisfy | fills a predetermined condition. Examples of the light oil fraction base material include hydrorefined light oil, hydrodesulfurized light oil, hydrocracked light oil, natural gas, asphalt, synthetic light oil synthesized from coal, and the like. Examples of the kerosene fraction base material include hydrorefined kerosene, hydrodesulfurized kerosene, hydrocracked kerosene, natural gas, asphalt, and synthetic kerosene synthesized from raw materials such as coal.

  The sulfur content of the hydrorefined oil according to the present invention needs to be 800 ppm by mass or less from the viewpoint of reducing harmful exhaust components discharged from off-road engines and improving the performance of exhaust gas aftertreatment devices, preferably It is 700 mass ppm or less, More preferably, it is 600 mass ppm or less, More preferably, it is 500 mass ppm or less. In addition, the sulfur content here means the mass content of the sulfur content based on the total amount of A heavy oil composition measured by JIS K2541 “Sulfur content test method”.

  The monocyclic naphthene content of the hydrorefined oil according to the present invention needs to be 10% by volume or more, preferably 15% by volume or more, and more preferably 20% by volume or more. When the content of monocyclic naphthene in the hydrorefined oil is within the above range, the properties defined in the A heavy oil composition of the present invention can be achieved more easily and reliably, and the fatty acid alkyl ester mixture and The synergistic effect can be achieved. Here, the content of 1-ring naphthene is the volume percentage of 1-ring naphthene measured according to ASTM D2786 “Standard Test Method for Hydrocarbon Types Analysis of Gas-Oil Saturates Fractions by High Ionizing Voltage Mass Spectrometry”. (Capacity%).

  The monocyclic aromatic content of the hydrorefined oil according to the present invention needs to be 20% by volume or less, preferably 17% by volume or less, more preferably 15% by volume or less, More preferably, it is 12 volume% or less. When the aromatic content of the hydrorefined oil is within the above range, the properties defined in the A heavy oil composition of the present invention can be achieved more easily and reliably, and the fatty acid alkyl ester mixture Synergy can be achieved. The monocyclic aromatic content mentioned here is based on the JPI-5S-49-97 “Hydrocarbon Type Test Method—High Performance Liquid Chromatograph Method” published by the Japan Petroleum Institute. It means the volume percentage (volume%) of the monocyclic aromatic content to be measured.

  The 90% distillation temperature (hereinafter also referred to as T90) of the hydrorefined oil according to the present invention is 280 ° C. or higher in order to suppress adverse effects on operating performance and the like associated with excessive lightening of distillation properties. It is necessary to be, preferably 290 ° C. or higher, more preferably 300 ° C. or higher. The T90 needs to be 350 ° C. or less, preferably 340 ° C. or less, more preferably 330 ° C. or less, from the viewpoint of suppressing an increase in particulate matter (PM) discharged from the off-road engine. It is. The 90% distillation temperature here means a value measured by JIS K 2254 “Petroleum product-distillation test method”.

  The difference between the 80% distillation temperature (hereinafter also referred to as T80) and the 20% distillation temperature (hereinafter also referred to as T20) of the hydrorefined oil according to the present invention is synergistic with the fatty acid alkyl ester mixture. In order to express the action, it is necessary to be 50 ° C. or higher, preferably 60 ° C. or higher, more preferably 70 ° C. or higher, and further preferably 80 ° C. or higher. Similarly, the difference between T80 and T20 needs to be 150 ° C. or less, preferably 140 ° C. or less, more preferably 130 ° C. or less, and further preferably 120 ° C. or less. Here, the 80% distillation temperature and the 20% distillation temperature mean values measured by JIS K 2254 “Petroleum products-distillation test method”.

In the present invention, it is necessary to mix an appropriate amount of a fatty acid alkyl ester mixture containing a specific fatty acid alkyl ester compound with the above-described hydrorefined oil.
As the fatty acid alkyl ester mixture, a glyceride compound (animal oil, vegetable oil) composed of fatty acid and glycerin produced from animal lipid parts and plant seeds as raw materials is generally used under an alkali catalyst (sodium methylate, caustic soda, etc.). And a mixture of fatty acid alkyl ester compounds obtained by separating and removing the remaining raw materials and by-products such as glycerin, catalyst, and the like. In the present invention, fatty acid alkyl ester compounds obtained by other chemical synthesis techniques can also be used.

Examples of the raw material of the animal lipid part include beef tallow, milk lipid (butter), pork tallow, sheep fat, whale oil, fish oil, liver oil, and the like. Then, it is desirable to use vegetable oil as a raw material.
Examples of vegetable oil raw materials include coconut palm, palm palm, olive, Benibana, rapeseed (rapeseed flower), rice bran, sunflower, cottonseed, corn, seeds such as soybeans and sesame, and other parts.
Moreover, in this invention, the waste oil which used these animal oils and vegetable oils for consumer use, industrial use, food use etc. can also be used as a raw material after adding the removal process of miscellaneous matters.

As a typical composition of the fatty acid portion of the glyceride compound contained in these raw materials, butyric acid (C ₃ H ₇ COOH), which is a fatty acid having no unsaturated bond in the molecular structure called saturated fatty acid, caproic acid ( C ₅ H ₁₁ COOH), caprylic acid (C ₇ H ₁₅ COOH), capric acid (C ₉ H ₁₉ COOH), lauric acid (C ₁₁ H ₂₃ COOH), myristic acid (C ₁₃ H ₂₇ COOH), palmitic acid ( C ₁₅ H ₃₁ COOH), stearic acid (C ₁₇ H ₃₅ COOH), and oleic acid (C ₁₇ H ₃₃ COOH), which is an unsaturated fatty acid having one or more unsaturated bonds, linoleic acid (C ₁₇ H ₃₁ COOH) ), linolenic acid _{(C 17} H 29 COOH), ricinoleic acid _{(C 17 H 32 (OH)} COOH) Hitoshigakyo It is. The hydrocarbon part of these fatty acids in natural substances is generally linear, but it is used in the present invention even if it has a structure having a side chain, that is, an isomer, as long as the properties defined in the present invention are satisfied. be able to. Further, the position of the unsaturated bond in the molecule of the unsaturated fatty acid is not limited to those generally found in nature as long as the properties defined in the present invention are satisfied in the present invention. The set one can also be used.

  The above-mentioned raw material oils (animal oil, vegetable oil) have one or more of these fatty acids, and the fatty acids they have differ depending on the raw material. For example, coconut oil has a relatively large amount of saturated fatty acids such as lauric acid and myristic acid, while soybean oil has a large amount of unsaturated fatty acids such as oleic acid and linoleic acid.

  In the present invention, the method for producing the fatty acid alkyl ester mixture is not particularly limited. As a typical example, stirring is performed at 70 ° C. for about 1 hour in the presence of an alkali catalyst (sodium methylate, caustic soda, etc.) Fatty acid by hydrolyzing raw material oil in a method of obtaining ester compound by directly reacting with alcohol (transesterification reaction) or high temperature and high pressure process (50-60 atm, 250-260 ° C, reaction for 2-3 hours, no catalyst) And glycerin, and the fatty acid obtained is reacted with an alkyl alcohol in the presence of an acid catalyst (sulfuric acid, PTS) to obtain an ester compound (esterification reaction).

Examples of the alkyl alcohol compound include methanol (CH ₃ OH), ethanol (C ₂ H ₅ OH), propanol (C ₃ H ₇ OH), butanol (C ₄ H ₉ OH), hexanol (C ₅ H ₁₁ OH) and the like. These isomers can also be used, but it is preferable to use methanol and ethanol mainly from the viewpoints of economy and property stabilization upon esterification.

Examples of the methyl ester compound obtained by the production method include butyric acid methyl ester (C ₃ H ₇ COOCH ₃ ), caproic acid methyl ester (C ₅ H ₁₁ COOCH ₃ ), caprylic acid methyl ester (C ₇ H ₁₅ COOCH ₃ ), Capric acid methyl ester (C ₉ H ₁₉ COOCH ₃ ), lauric acid methyl ester (C ₁₁ H ₂₃ COOCH ₃ ), myristic acid methyl ester (C ₁₃ H ₂₇ COOCH ₃ ), palmitic acid methyl ester (C ₁₅ H ₃₁ COOCH ₃₎ ), methyl stearate _{(C 17 H 35 COOCH 3)} , methyl oleate _{(C 17 H 33 COOCH 3)} , linoleic acid methyl ester _{(C 17 H 31 COOCH 3)} , linolenic acid methyl ester _(C 17 _{H 2} COOCH _3), as the ricinoleic acid methyl ester _{(C 17 H 32 (OH)} COOCH 3) or the like, also ethyl ester compound, butyric acid ethyl ester _{(C 3 H 7 COOC 2 H} 5), caproic acid ethyl ester _{(C 5} H ₁₁ COOC ₂ H ₅ ), caprylic acid ethyl ester (C ₇ H ₁₅ COOC ₂ H ₅ ), capric acid ethyl ester (C ₉ H ₁₉ COOC ₂ H ₅ ), lauric acid ethyl ester (C ₁₁ H ₂₃ COOC ₂ H ₅ ), myristic acid ethyl ester (C ₁₃ H ₂₇ COOC ₂ H ₅ ), palmitic acid ethyl ester (C ₁₅ H ₃₁ COOC ₂ H ₅ ), stearic acid ethyl ester (C ₁₇ H ₃₅ COOC ₂ H ₅ ), oleic acid ethyl ester _{(C 17 H 33 COOC 2 H} 5) Linoleic acid ethyl ester _{(C 17 H 31 COOC 2 H} 5), linolenic acid ethyl ester _{(C 17 H 29 COOC 2 H} 5), ricinoleic acid ethyl ester _{(C 17 H 32 (OH)} COOC 2 H 5) or the like include It is done.

Quantification of these fatty acid alkyl ester compounds and raw fatty acids can be carried out using a gas chromatograph. Analytical conditions are shown below. By using a free fatty acid type column (FFAP), these substances can be easily and accurately quantified.
Column: FFAP (φ0.32mm × 25m)
Carrier gas: He (26 psi)
Detector: FID
Injection temperature: 280 ° C
Detector temperature: 300 ° C
Oven temperature: 100-260 ° C (10 minutes)
Temperature increase rate: 5 ° C./min Injection amount: 0.4 μL (methanol solution)

  In the present invention, it is necessary to blend an appropriate amount of a fatty acid alkyl ester mixture having at least two kinds of specific fatty acid alkyl ester compounds and satisfying predetermined properties into the hydrorefined oil. Specifically, among the fatty acid alkyl ester compounds described above, one or more of fatty acid alkyl ester compounds (A) selected from myristic acid alkyl esters, palmitic acid alkyl esters, and stearic acid alkyl esters must be contained. Moreover, it must contain at least one of fatty acid alkyl ester compounds (B) selected from lauric acid alkyl esters, oleic acid alkyl esters, linoleic acid alkyl esters and linolenic acid alkyl esters. Moreover, the value which remove | divided (B) by the sum total of the mass content of below-mentioned four types of fatty-acid alkylester compound (B) for the sum total of the mass content of the above-mentioned three types of fatty-acid alkylester compound (A) at this time ( C), that is, C = the sum of the mass contents of the fatty acid alkyl ester (A) / the sum of the mass contents of the fatty acid alkyl ester (B) needs to be 0.1 or more. This value is an index that represents the overall characteristics of the fatty acid alkyl ester mixture. If this value is small, the fluidity at low temperatures will deteriorate. Since the present A heavy oil composition is required to have performance equivalent to JIS standard No. 1 heavy oil, this value needs to be 0.1 or more, preferably 0.2 or more. Is more preferably 3 or more, and further preferably 0.4 or more. Further, if this value is excessively large, the exhaust gas performance deteriorates, and in order to have a fluidity improving effect in the category of JIS standard No. 1 heavy oil, it is necessary to be 2.0 or less, 1.8 Or less, more preferably 1.6 or less, and even more preferably 1.4 or less.

  The average molecular weight of the fatty acid alkyl ester mixture blended in the A heavy oil composition of the present invention needs to be 500 or less. The average molecular weight means an average molecular weight obtained by multiplying the content ratio of the contained compound and the molecular weight. If this value is excessively large, the fluidity tends to deteriorate at low temperatures, so it is necessary that it is 500 or less, preferably 450 or less, and more preferably 400 or less.

  Moreover, the total acid value of the fatty acid alkyl ester mixture blended in the A heavy oil composition of the present invention is required to be 1.0 mgKOH / g or less. Since the total acid value indicates the amount of free fatty acid in the mixture, if this value is large, there is a concern that the acidic compound may adversely affect the member. Therefore, the total acid value needs to be 1.0 mgKOH / g or less, desirably 0.9 mgKOH / g or less, and more preferably 0.8 mgKOH / g or less. The total acid value as used herein means the total acid value measured according to JIS K 2501 “Petroleum products and lubricating oils—neutralization number test method”.

  The sulfur content of the fatty acid alkyl ester mixture blended in the A heavy oil composition of the present invention is required to be 5 ppm by mass or less. When the sulfur content is high, the exhaust gas aftertreatment device installed in the off-road engine has a significant adverse effect, and since there is no sulfur content in the esterification reaction, contamination with multiple components is considered. The sulfur content is required to be 5 ppm by mass or less, preferably 4 ppm by mass or less, more preferably 3 ppm by mass or less, still more preferably 2 ppm by mass or less. Most preferably, it is at most ppm by mass. In addition, the sulfur content here means the mass content of the sulfur content based on the total amount of the mixture measured by JIS K2541 “Sulfur content test method”.

The A heavy oil composition in the present invention can be obtained by blending an appropriate amount of the hydrorefined oil having the predetermined properties and the fatty acid alkyl ester mixture having the predetermined properties. The blending ratio of both must satisfy the following formula.
RBDF = (− 6 × C × FAME + HDS × (2 × PA + PN)) / 100
0 ≦ RBDF ≦ 10
RBDF: BDF index
C: Sum of mass content of fatty acid alkyl ester (A) / fatty acid alkyl ester
Sum of mass content of ru (B) FAME: Fatty acid alkyl ester mixture content (volume%)
HDS: Hydrorefined oil content (volume%)
PA: Aromatic content of 2 or more rings in hydrorefined oil (volume%)
PN: Content of naphthene in two or more rings in hydrorefined oil (volume%)

Here, the RBDF is referred to as a BDF index. The BDF index is a relational expression found by the present inventors through a number of experiments, and displays the following contents.
Although it is well known that aromatic compounds having two or more rings in the fuel (polycyclic aromatic components) adversely affect PM, nitrogen oxides (NOx), etc., they are heavy naphthenic compounds having two or more rings (polyhydric compounds). The present inventors have grasped that the amount of ring naphthene is also an adverse factor. At the same time, when the influence on the low-temperature flow performance was taken into consideration, the degree of influence was the ratio of the polycyclic naphthene content 1 to the polycyclic aromatic content 2.

  On the other hand, since the fatty acid alkyl ester mixture is an oxygen-containing compound and has a structure that easily undergoes thermal decomposition, it has the effect of suppressing PM generation and improving combustion, and improving fuel efficiency and output. On the other hand, it has factors that cause deterioration of NOx emissions and low temperature fluidity. The present inventors have grasped that these phenomena are largely caused by the influence of the fatty acid structure of the fatty acid alkyl ester mixture and the content ratio of the specific saturated fatty acid and the specific unsaturated fatty acid. At the same time, the content ratio has a great influence on the low-temperature flow performance. Although lauric acid is a saturated fatty acid, the present inventors have found that these behaviors are similar to those of unsaturated fatty acids. Therefore, lauric acid is treated as an unsaturated fatty acid and is not useful when calculating the content ratio. We decided to rate the sum of saturated fatty acids and lauric acid.

  As a result of examining the influence of the polycyclic aromatic component and the polycyclic naphthene and the degree of influence of the fatty acid alkyl ester mixture, the present inventors have found that these have a first-order correlation. In view of combustibility, low-temperature flow performance, etc., the influence of these three factors is: fatty acid alkyl ester mixture: −6 × (content of specific saturated fatty acid alkyl ester / (unsaturated fatty acid alkyl ester and lauric acid alkyl ester )), Polycyclic aromatic content: 2, polycyclic naphthene content: 1 was found. In other words, the production of this relational expression at this ratio makes it possible to obtain fuel quality that simultaneously improves combustibility, low temperature performance, and the like.

  This means that the fatty acid alkyl ester compound, the polycyclic aromatic compound, and the polycyclic naphthene compound have a large degree of influence on the flammability and that the direction works in reverse.

  In the A heavy oil composition according to the present invention, the properties and effects defined in the A heavy oil composition of the present invention can be achieved more easily and reliably, and a synergistic action with the fatty acid alkyl ester mixture is achieved. The RBDF represented by the above formula needs to be 0 or more, preferably 1 or more, more preferably 2 or more, further preferably 3 or more, and 4 or more. Even more preferred is 5 or greater. For the same reason, the RBDF represented by the above formula needs to be 10 or less, preferably 9 or less, and more preferably 8 or less.

  In the present invention, the amount of the fatty acid alkyl ester mixture is not limited as long as the above conditions are satisfied. However, in order to easily and reliably obtain the properties and effects of the present invention, the A heavy oil composition Based on the total amount, it is preferably 3% by volume or more, more preferably 5% by volume or more, further preferably 7% by volume or more, and particularly preferably 10% by volume or more. Similarly, the amount of the fatty acid alkyl ester mixture is preferably 50% by volume or less, more preferably 45% by volume or less, and further preferably 40% by volume or less. When the blended amount of the fatty acid alkyl ester mixture is extremely large, a problem arises in the oxidation stability of the fuel and the predetermined effect cannot be exhibited.

In addition, a residual carbon base material is mix | blended with the A heavy oil composition of this invention as needed.
The type of the residual carbon content-imparting base material is not particularly limited, and examples thereof include normal pressure residual oil, residual oil desulfurized heavy oil, reduced pressure residual oil, slurry oil, and extract oil. These may be used alone or in combination of two or more. Used in combination. Here, the atmospheric residual oil is a residual oil obtained by distilling crude oil at atmospheric pressure using an atmospheric distillation apparatus. The residual oil desulfurized heavy oil is a heavy oil obtained when a normal pressure residual oil or a vacuum residual oil is desulfurized in a residual oil desulfurization apparatus. The vacuum residue is a residue obtained by distilling atmospheric residue under reduced pressure using a vacuum distillation apparatus. A slurry oil is a residual oil obtained from a fluid catalytic cracking apparatus. Extract oil is an aromatic component that is not suitable for lubricating oil among the fractions extracted from the vacuum distillation apparatus for lubricating oil raw material by solvent extraction.

The bulk modulus of the A heavy oil composition of the present invention needs to be 1350 MPa or more and 1550 MPa or less.
In general, when a high pressure is applied to a compressible fluid such as light oil, the fluid itself is compressed according to the temperature and pressure at that place, and the density (volume per flow rate) changes. The compression elastic modulus of this object is defined as the bulk elastic modulus (unit: MPa). Assuming diesel fuel injection, the volume modulus of elasticity for the fuel fluid changes at a constant rate according to the physical characteristics and composition of the fuel itself as well as the temperature and pressure of the atmosphere in which the fuel is placed. Therefore, in an injection system having high-pressure and high-precision injection characteristics, such as an electronically controlled fuel injection pump, in order to maintain the fuel injection amount and injection rate as set, the volume elastic modulus shows a stable value. Fuel is needed. The stabilization of this value leads to the reduction of NOx, PM, fine particles and the like. Therefore, in the A heavy oil composition of the present invention, the volume modulus of elasticity needs to be 1350 MPa or more and 1550 MPa or less, and preferably 1370 MPa or more and 1500 MPa or less.

Note that the bulk modulus is not governed by a single fuel physical property or composition, but is defined as a result of multiple effects of multiple physical properties and compositions. From the technical point of view, it is reasonable to think of it as a fuel characteristic that should be considered in parallel with the composition.
There is no officially determined method for measuring the bulk modulus at this time, but an outline will be described. The fuel to be measured is sealed in a constant volume container made of a material and structure that can prove that the volume change of the container itself due to temperature and pressure changes is sufficiently small with respect to the fuel volume change in the same environmental change. . At this time, the container needs to be filled only with the fuel to be measured. A constant volume piston made of a material and a structure capable of demonstrating that the volume change of the piston itself due to changes in temperature and pressure is sufficiently small with respect to the volume change of the fuel in the same environmental change is inserted into this constant volume container, Change the container volume. Since the fuel to be measured is compressed according to its compression elastic characteristic, the pressure in the container changes as a result. By measuring this pressure, the bulk modulus is calculated.

  In the A heavy oil composition of the present invention, from the viewpoint of storage stability, the total insoluble content after the oxidation stability test needs to be 2.0 mg / 100 mL or less, and is 1.5 mg / 100 mL or less. It is preferably 1.0 mg / 100 mL or less, and more preferably 0.5 mg / 100 mL or less. The oxidation stability test here is conducted under conditions of 95 ° C. and oxygen bubbling for 16 hours in accordance with ASTM D2274-94. The total insoluble matter after the oxidation stability test here means a value measured in accordance with the oxidation stability test.

  In the heavy oil composition A of the present invention, the peroxide value after the oxidation stability test is preferably 10 ppm by mass or less, more preferably 5 ppm by mass or less, from the viewpoint of storage stability and compatibility with members. Preferably it is 2 mass ppm or less, Most preferably, it is 1 mass ppm or less. Here, the peroxide value means a value measured in accordance with the Petroleum Institute Standard JPI-5S-46-96.

  In order to reduce the total insoluble matter and the peroxide value, additives such as an antioxidant and a metal deactivator can be appropriately added to the A heavy oil composition of the present invention.

The A heavy oil composition in the present invention needs to satisfy the JIS No. 1 heavy oil standard. The JIS No. 1 heavy oil standard is a standard that satisfies “Type No. 1” defined in JIS K 2204 “Heavy oil”. Specifically, the flash point is 60 ° C. or higher, the pour point is 5 ° C. or lower, and the residual carbon content is 4 mass. % Or less, a kinematic viscosity at 50 ° C. of 20 mm ² / s or less, and a sulfur content of 0.5% by mass or less.

  The flash point of the heavy oil composition A of the present invention needs to satisfy JIS No. 1 heavy oil standard of 60 ° C. or higher. If the flash point is less than 60 ° C., it cannot be handled as a heavy fuel oil composition for safety reasons. For the same reason, the flash point is preferably 62 ° C. or higher, and more preferably 64 ° C. or higher. The flash point in the present invention is a value measured by JIS K 2265 “Crude oil and petroleum product flash point test method”.

  The cetane index of the A heavy oil composition of the present invention is preferably 40 or more. When the cetane index is less than 40, the concentration of PM, aldehydes, or NOx in the exhaust gas tends to increase. For the same reason, the cetane index is more preferably 42 or more. The cetane index referred to in the present invention is defined by “Method of calculating cetane index using 8.4 variable equation” in JIS K 2280 “Petroleum products-fuel oil-octane number and cetane number test method and cetane index calculation method”. It means the calculated value. Here, the cetane index in the JIS standard is generally applied to light oil to which no cetane number improver is added. However, in the present invention, the cetane index is also applied to the A heavy oil composition to which a cetane number improver is added. Applying “8.4 Calculation Method of Cetane Index Using Variable Equation”, a value calculated by the calculation method is expressed as a cetane index.

  The cetane number of the A heavy oil composition of the present invention is preferably 40 or more, more preferably 42 or more, and still more preferably 44 or more. When the cetane number is less than 40, the concentration of NOx, PM and aldehydes in the exhaust gas tends to be high. Further, from the viewpoint of reducing black smoke in the exhaust gas, the cetane number is preferably 80 or less, more preferably 75 or less, and further preferably 70 or less. The cetane number referred to here is a cetane number measured in accordance with “7. Cetane number test method” in JIS K 2280 “Petroleum products—Fuel oil—Octane number and cetane number test method and cetane index calculation method”. Means.

In the A heavy oil composition of the present invention, an appropriate amount of a cetane number improver can be blended as necessary to improve the cetane number of the obtained A heavy oil composition.
As the cetane number improver, various compounds known as cetane number improvers can be arbitrarily used, and examples thereof include nitrate esters and organic peroxides. These cetane number improvers may be used alone or in combination of two or more.

  In the present invention, it is preferable to use a nitrate ester among the cetane number improvers described above. Such nitrate esters include 2-chloroethyl nitrate, 2-ethoxyethyl nitrate, isopropyl nitrate, butyl nitrate, primary amyl nitrate, secondary amyl nitrate, isoamyl nitrate, primary hexyl nitrate, Various nitrates such as secondary hexyl nitrate, n-heptyl nitrate, n-octyl nitrate, 2-ethylhexyl nitrate, cyclohexyl nitrate, and ethylene glycol dinitrate are included. An alkyl nitrate of 6-8 is preferred.

  The content of the cetane improver is preferably 500 ppm by mass or more based on the total amount of the composition, more preferably 600 ppm by mass or more, further preferably 700 ppm by mass or more, and 800 ppm by mass or more. Even more preferably, it is most preferably 900 ppm by mass or more. When the content of the cetane improver is less than 500 ppm by mass, a sufficient cetane number improving effect cannot be obtained, and PM, aldehydes, and further NOx in off-road engine exhaust gas tend not to be sufficiently reduced. is there. Moreover, the upper limit of the content of the cetane number improver is not particularly limited, but is preferably 1400 mass ppm or less, more preferably 1250 mass ppm or less, based on the total amount of the heavy oil A composition, and 1100 mass ppm. Or less, and most preferably 1000 ppm by mass or less.

  As the cetane number improver, one synthesized according to a conventional method may be used, or a commercially available product may be used. In addition, what is marketed as a cetane number improver is usually obtained in a state where an active ingredient contributing to cetane number improvement (that is, cetane number improver itself) is diluted with an appropriate solvent. When preparing the A heavy oil composition of this invention using such a commercial item, it is preferable that content of the said active ingredient in A heavy oil composition becomes in the above-mentioned range.

In the A heavy oil composition of the present invention, additives other than the cetane number improver can be blended as necessary, and in particular, a lubricity improver and / or a detergent is preferably blended.
As the lubricity improver, for example, one or more of carboxylic acid-based, ester-based, alcohol-based, and phenol-based lubricity improvers can be arbitrarily used. Among these, carboxylic acid-based and ester-based lubricity improvers are preferable.
Examples of the carboxylic acid-based lubricity improver include linoleic acid, oleic acid, salicylic acid, palmitic acid, myristic acid, hexadecenoic acid and a mixture of two or more of the above carboxylic acids.
Examples of ester-based lubricity improvers include carboxylic acid esters of glycerin. The carboxylic acid constituting the carboxylic acid ester may be one kind or two or more kinds, and specific examples thereof include linoleic acid, oleic acid, salicylic acid, palmitic acid, myristic acid, hexadecenoic acid and the like. There is.

  The blending amount of the lubricity improver is not particularly limited as long as the HFRR wear scar diameter (WS1.4) is within a preferable range described later, but is preferably 35 ppm by mass or more based on the total amount of the composition, and 50 ppm by mass. More preferably. When the blending amount of the lubricity improver is within the above range, the effectiveness of the blended lubricity improving agent can be effectively extracted. For example, in an off-road engine equipped with a distribution type injection pump, An increase in pump driving torque can be suppressed, and pump wear can be reduced. Further, the upper limit of the blending amount is preferably 150 mass ppm or less on the basis of the total amount of the composition, and more preferably 105 mass ppm or less because an effect commensurate with the addition amount cannot be obtained even if it is added more. preferable.

  As in the case of the cetane number improver, what is marketed as a lubricity improver is obtained in a state where the active ingredient contributing to the improvement of lubricity is diluted with an appropriate solvent. It is customary. When blending such a commercial product in the A heavy oil composition of the present invention, the content of the active ingredient in the A heavy oil composition is preferably within the above range.

Further, for the purpose of further improving the performance of the A heavy oil composition of the present invention, other known fuel oil additives (hereinafter referred to as “other additives” for convenience) to be described later are added alone or in combination of several kinds. You can also. Other additives include, for example, low-temperature fluidity improvers such as ethylene-vinyl acetate copolymer and alkenyl succinic acid amide; antioxidants such as phenols and amines; metal deactivators such as salicylidene derivatives; Anti-icing agents such as polyglycol ethers; corrosion inhibitors such as aliphatic amines and alkenyl succinic acid esters; antistatic agents such as anionic, cationic and amphoteric surfactants; colorants such as azo dyes; Antifoaming agents and the like.
Although the addition amount of other additives can be arbitrarily determined, the addition amount of each additive is preferably 0.5% by mass or less, more preferably 0.2% by mass or less, based on the total amount of A heavy oil composition. It is.

The density at 15 ℃ of A fuel oil composition of the present invention, in terms of calorific value ensuring, is preferably 800 kg / ^{m 3} or more, more preferably 805kg / ^{m 3} or more, 810kg / ^{m 3} or more and more preferable. Further, the density, NOx, from the viewpoint of reducing the emission of PM, it is preferably 850 kg / ^{m 3} or less, more preferably 845 kg / ^{m 3} or less, more preferably 840 kg / ^{m 3} or less. In addition, the density here means the density measured by JIS K 2249 “Density test method and density / mass / capacity conversion table of crude oil and petroleum products”.

The A heavy oil composition of the present invention desirably has a lubricating performance such that the HFRR wear scar diameter (WS 1.4) is preferably 410 μm or less, more preferably 380 μm or less. When the HFRR wear scar diameter (WS1.4) exceeds 410 μm, particularly in an off-road engine equipped with a distribution type injection pump, the driving torque of the pump during operation and the wear of each part of the pump are increased, exhaust gas performance, The off-road engine itself may be destroyed as well as the fine particle performance deteriorates. In addition, in an electronically controlled fuel injection pump capable of high-pressure injection, there is a concern about wear on the sliding surface.
The HFRR wear scar diameter (WS1.4) as used in the present invention is a value measured by the Petroleum Institute Standard JPI-5S-50-98 “Light Oil-Lubricity Test Method” issued by the Japan Petroleum Institute. Means.

  The sulfur content of the heavy fuel oil composition A of the present invention is not particularly limited as long as the hydrorefined oil and the fatty acid alkyl ester mixture satisfy a predetermined value, but in order to enhance the environmental load reduction effect, 8 mass ppm. Is preferably 5 mass ppm or less, more preferably 3 mass ppm or less, still more preferably 1 mass ppm or less. The content of sulfur as used herein means the content of sulfur based on the total amount of A heavy oil composition, measured by JIS K 2541 “Sulfur content test method”.

  The aromatic content of the A heavy oil composition of the present invention is not particularly limited as long as the hydrorefined oil and the fatty acid alkyl ester mixture satisfy a predetermined value, but the environmental load reduction effect is enhanced, and NOx and PM are reduced. In view of the above, it is preferably 20% by volume or less, more preferably 15% by volume or less, and still more preferably 10% by volume or less. The aromatic content is preferably 3% by volume or more, and more preferably 5% by volume or more. If the aromatic content is less than 3% by volume, there is a concern about the influence on the material used for the injection pump.

  The naphthene compound content of the heavy fuel oil composition A of the present invention is not particularly limited as long as the hydrorefined oil and the fatty acid alkyl ester mixture satisfy a predetermined value, but in order to increase the environmental impact reduction effect, the naphthene compound The content is preferably 95% by volume or less, more preferably 90% by volume or less, still more preferably 85% by volume or less, and most preferably 80% by volume or less. The naphthene compound content is preferably 10% by volume or more, more preferably 20% by volume or more, and further preferably 30% by volume or more from the viewpoint of fuel economy and output improvement. In addition, the naphthene compound content in the present invention is a volume percentage (volume%) of naphthene measured in accordance with ASTM D2786 “Standard Test Method for Hydrocarbon Types Analysis of Gas-Oil Saturates Fractions by High Ionizing Voltage Mass Spectrometry”. ).

  The water content of the A heavy oil composition of the present invention is preferably 800 ppm by volume or less, preferably 700 ppm by volume or less, from the viewpoint of adverse effects on members to fuel tanks and the like and suppression of ester compound hydrolysis. More preferably, it is more preferably 600 ppm by volume or less. In addition, the water | moisture content here is the water prescribed | regulated by JISK2275 "moisture test method (crude oil and petroleum products)."

  The clogging point (CFPP) of the heavy fuel oil composition A of the present invention is preferably −3 ° C. or less, more preferably −5 ° C. or less, from the viewpoint of preventing pre-filter blockage of off-road diesel vehicles. . Here, the clogging point refers to a clogging point measured according to JIS K 2288 “Light oil—clogging point test method”.

  The pour point of the A heavy oil composition of the present invention needs to satisfy JIS No. 1 heavy oil standard of 5 ° C. or lower. Furthermore, from the viewpoint of low temperature startability or low temperature drivability, and from the viewpoint of maintaining injection performance in the electronically controlled fuel injection pump, it is preferably −2.5 ° C. or lower, and more preferably −5 ° C. or lower. Here, the pour point means a pour point measured by JIS K 2269 “Pour point of crude oil and petroleum products and cloud point test method of petroleum products”.

  As distillation characteristics in the heavy oil composition A of the present invention, it is preferable that the hydrorefined oil and the fatty acid alkyl ester mixture satisfy a predetermined value, and the 90% distillation temperature is 360 ° C. or lower. More preferably, it is 350 degrees C or less, More preferably, it is 340 degrees C or less, Most preferably, it is 330 degrees C or less. When the 90% distillation temperature exceeds 360 ° C., the amount of PM and fine particles discharged tends to increase. The 90% distillation temperature is preferably 280 ° C. or higher, more preferably 285 ° C. or higher, further preferably 290 ° C. or higher, even more preferably 295 ° C. or higher, and most preferably 300 ° C. or higher. If the 90% distillation temperature is less than 280 ° C., the fuel efficiency improvement effect becomes insufficient, and the output of the off-road engine tends to decrease. Although there is no restriction | limiting in particular in 10% distillation temperature, Preferably it is 250 degrees C or less, More preferably, it is 240 degrees C or less, More preferably, it is 230 degrees C or less, More preferably, it is 220 degrees C or less. If the 10% distillation temperature exceeds 250 ° C, the exhaust gas performance tends to deteriorate. The 10% distillation temperature is preferably 160 ° C or higher, more preferably 170 ° C or higher, and further preferably 180 ° C or higher. If the 10% distillation temperature is less than 160 ° C, the output of the off-road engine and the startability at high temperatures tend to deteriorate. The 10% distillation temperature and 90% distillation temperature here mean values measured by JIS K 2254 “Petroleum product-distillation test method”.

The kinematic viscosity at 50 ° C. of the heavy fuel oil composition A of the present invention is preferably such that the hydrorefined oil and fatty acid alkyl ester mixture satisfies a predetermined value and is 2.0 mm ² / s or more, and 2.2 mm ² / s More preferably, it is s or more. When the kinematic viscosity is less than 2.0 mm ² / s, it tends to be difficult to control the fuel injection timing on the fuel injection pump side, and lubricity in each part of the fuel injection pump mounted on the off-road engine May be damaged. Further, the kinematic viscosity at 50 ° C. of the A heavy oil composition of the present invention is preferably 5 mm ² / s or less, more preferably 4.8 mm ² / s or less, and 4.5 mm ² / s or less. More preferably. If the kinematic viscosity exceeds 5 mm ² / s, the resistance inside the fuel injection system increases, the injection system becomes unstable, and the concentrations of NOx and PM in the exhaust gas increase. In addition, kinematic viscosity here means kinematic viscosity measured by JISK2283 "crude oil and petroleum products-kinematic viscosity test method and viscosity index calculation method".

  The carbon content of the A heavy oil composition of the present invention must satisfy 4% by mass or less, which is JIS No. 1 heavy oil standard. Furthermore, it is preferably 3% by mass or less, more preferably 2% by mass or less from the viewpoint of reducing fine particles and PM and maintaining the performance of the exhaust gas aftertreatment device mounted on the off-road engine. . In addition, a residual carbon content here means the residual carbon content measured by JISK2270 "Crude oil and petroleum products-residual carbon content test method".

In the A heavy oil composition of the present invention, the ash content is preferably 0.01% by mass or less. If the ash content exceeds the upper limit, the ash becomes the core of PM during the combustion process in the off-road engine, and the total amount of PM and the amount of nanoparticles increase. Further, even when the ash is discharged as it is, the ash is deposited on the exhaust gas post-processing device, and the performance of the post-processing device may be deteriorated. Furthermore, an adverse effect on the fuel injection system can be considered.
The ash content in the present invention means a value measured by JIS K 2272 “Crude oil and petroleum product ash content and sulfate ash test method”.

Moreover, the electrical conductivity of the A heavy oil composition of the present invention is not particularly limited, but is preferably 50 pS / m or more from the viewpoint of safety.
In order to improve electrical conductivity, an antistatic agent or the like can be appropriately added to the A heavy oil composition of the present invention. Here, the conductivity means a value measured in accordance with JIS K 2276 “Petroleum products—aviation fuel oil test method”.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example and a comparative example, this invention is not limited to these Examples at all.

(Examples 1-5 and Comparative Example 1)
Additives were blended with the hydrorefined oil having the properties shown in Table 1, the residual carbon base material, and the fatty acid alkyl ester mixture to prepare A heavy oil compositions shown in Table 2 (Examples 1 to 5 and Comparative Example 1). ).
In addition, the additive used was as follows.
Cetane number improver: 2-ethylhexyl nitrate Lubricant improver: Carboxylic acid mixture based on linoleic acid Low temperature fluidity improver: Ethylene-vinyl acetate copolymer

  The blending ratio of the blended A fuel oil composition, and the blended A fuel oil composition, density at 15 ° C., kinematic viscosity at 50 ° C., flash point, sulfur content, distillation properties, cetane number and cetane index, Results of measuring pour point, clogging point, residual carbon content of 10% residual oil, volume modulus, ash content, moisture, total insoluble matter after oxidation stability test, peroxide value, conductivity, wear scar diameter It shows in Table 2.

The properties of the fuel oil were measured by the following method.
The density refers to a density measured according to JIS K 2249 “Determination method of density of crude oil and petroleum products and density / mass / capacity conversion table”.
The kinematic viscosity refers to a kinematic viscosity measured according to JIS K 2283 “Crude oil and petroleum products—Kinematic viscosity test method and viscosity index calculation method”.
The sulfur content refers to the mass content of the sulfur content based on the total amount of A heavy oil composition measured by JIS K2541 “Sulfur content test method”.

All the distillation properties are values measured by JIS K 2254 "Petroleum products-Distillation test method".
The aromatic content and the aromatic content of two or more rings are determined by the Petroleum Institute Method JPI-5S-49-97 “Hydrocarbon Type Test Method—High Performance Liquid Chromatograph Method” published by the Japan Petroleum Institute. It means the volume percentage (volume%) of the aromatic content that has been observed and complied with.
The naphthene compound content means a volume percentage (volume%) of naphthene measured in accordance with ASTM D2786 “Standard Test Method for Hydrocarbon Types Analysis of Gas-Oil Saturates Fractions by High Ionizing Voltage Mass Spectrometry”.
Moisture means the moisture specified by JIS K 2275 “Moisture test method (crude oil and petroleum products)”.
The flash point indicates a value measured according to JIS K 2265 “Crude oil and petroleum product flash point test method”.
The total acid value means the total acid value measured according to JIS K 2501 “Petroleum products and lubricating oils—neutralization number test method”.

The cetane index refers to a value calculated according to “Method for calculating cetane index using 8.4 variable equation” in JIS K 2280 “Petroleum products—fuel oil—octane number and cetane number test method and cetane index calculation method”. The cetane index in the JIS standard is not applied to the cetane number improver added, but the cetane index of the cetane index added with the cetane number improver also uses the above “8.4 variable equation”. It shall represent the value calculated by “Calculating method of cetane index”.
The cetane number means a cetane number measured according to “7. Cetane number test method” of JIS K 2280 “Petroleum products—fuel oil—octane number and cetane number test method and cetane index calculation method”.

Lubrication performance and HFRR wear scar diameter (WS1.4) refer to the lubrication performance measured by the Petroleum Institute Standard JPI-5S-50-98 “Diesel Oil-Lubricity Test Method” published by the Japan Petroleum Institute. .
The clogging point refers to a clogging point measured by JIS K 2288 “Light oil—clogging point test method”.
The pour point refers to a pour point measured according to JIS K 2269 “Crude point of petroleum and petroleum products and a cloud point test method of petroleum products”.
The residual carbon content of 10% residual oil means the residual carbon content of 10% residual oil as measured by JIS K 2270 “Crude oil and petroleum products—residual carbon content test method”.
Ash content means a value measured by JIS K 2272 “Crude oil and petroleum product ash and sulfate ash test method”.
The total insoluble matter after the oxidation stability test means a value measured under conditions of 95 ° C. and oxygen bubbling for 16 hours in accordance with ASTM D2274-94.
The peroxide value means a value measured according to the Petroleum Institute Standard JPI-5S-46-96.
The conductivity means a value measured in accordance with JIS K 2276 “Petroleum product-aviation fuel oil test method”.

As shown in Table 2, A heavy oil compositions used in Examples and Comparative Examples are prepared by blending hydrorefined oil, residual carbon base material and fatty acid alkyl ester mixture at a specific blending ratio.
As is apparent from Table 2, 90% distillation temperature (T90), difference between 80% distillation temperature and 20% distillation temperature (T80-T20), sulfur content, 1-ring naphthene content, 1-ring Example 1 in which a mixture of a hydrorefined oil and a fatty acid alkyl ester, each having an aromatic content and an ester coefficient (C) within the range defined by the present invention, was blended within the range defined by the present invention. ~ 5, the A heavy oil composition satisfying the properties of JIS heavy oil and having a bulk modulus of 1350 MPa to 1550 MPa and a total insoluble matter after oxidation stability test of 2.0 mg / 100 mL or less can be easily obtained I was able to get it without fail. On the other hand, in the comparative example 1 which prepared A heavy oil composition, without using the said specific hydrorefined oil and fatty-acid alkylester mixture, the A heavy oil composition made into the objective of this invention is not necessarily obtained.

  Next, using each A heavy oil composition of Examples 1 to 5 and Comparative Example 1, various tests shown below were performed. All test results are shown in Table 3. As can be seen from the results in Table 3, the A heavy oil compositions of Examples 1 to 5 have better combustibility and low temperature startability than the A heavy oil composition of Comparative Example 1, and excellent rubber swelling performance. It is clear that

(Flammability performance evaluation)
The combustion performance was evaluated by measuring the ignition delay by the following method. Ignition delay adversely affects engine performance and exhaust gas, and is a major cause of trouble in recent high-performance engines. Using a fuel ignitability tester having a combustion chamber volume of 1 liter, fuel was injected into air having a pressure of 45 barrels and a temperature of 450 ° C., and the time from injection to ignition was measured as the ignition delay time. An ignition delay time of 5 ms or less was judged as good (◯), and 5 ms or more was judged as bad (x).

(Low temperature fluidity performance evaluation)
A 20 L pail can was prepared as a sample container, and a hole into which the sample suction tube was inserted was provided on the top surface of the pail can. The hole was formed at the midpoint of a straight line connecting the center of the upper surface and the point on the outer periphery. On the other hand, a copper tube having an outer diameter of 10 mm was prepared as a sample suction tube, and one end thereof was connected to an inlet of a filter (Nepon Corporation, code No. 120267) via a silicon rubber tube. Moreover, the outlet of the filter was connected to a suction pump through a copper tube. As the suction pump, a pump capable of adjusting the oil flow rate within a range of 1 to 10 L / hr was used.
Next, about 15 L of a sample (A heavy oil composition) having a temperature of 20 to 25 ° C. is put in the above-mentioned pail can, and a lid with a sample suction tube is put on the hole on the upper surface of the pail can. The pump was accommodated in a thermostat, the pump was driven, and the pump pressure was adjusted so that the oil flow rate was 9.5 ± 0.2 L / hr. As the low-temperature thermostatic bath, a thermostatic bath having a program temperature adjusting function and capable of cooling to −30 ° C. or less within a temperature system of ± 0.5 ° C. was used. After the pail can and the filter were accommodated in the low temperature thermostat, the inside of the low temperature thermostat was cooled with a predetermined temperature profile, and the suction pump was driven. More specifically, the sample was cooled from a temperature 8 ° C. higher than the cloud point of the sample to a predetermined temperature at a cooling rate of 1 ° C./hr. The temperature was held for 3 hours, and the oil passage limit was determined by measuring the pressure with a pressure gauge. Judgment of the oil passage limit is accepted when the differential pressure is 33 kPa (250 mmHg) or less during oil passage for 60 minutes at the holding temperature, and is rejected when it exceeds 33 kPa, and held at 1 ° C intervals until it fails. The test was repeated at a lower temperature. The highest temperature (clogging temperature) at which the judgment was rejected was used as an index for evaluating the low temperature performance. In addition, the sample was replaced with new oil for each test. A clogging temperature of -3 ° C. or lower was judged good (◯), and a temperature of −2 ° C. or higher was judged bad (x).

(Rubber swelling test)
In order to confirm the influence on the rubber member used in the O-ring or the like of the engine part, a soaking test was performed according to the following procedure. Acrylonitrile, one of the compounds composing rubber, has a combined acrylonitrile mass center value of nitrile rubber (medium nitrile rubber) that is 25% or more and 35% or less of the total as a rubber member to be evaluated, and conforms to MIL R6855 Then, the test fuel is heated and held at 100 ° C., and the test rubber member is immersed in it for 70 hours. Evaluation is made by comparing and quantifying the volume change of the test rubber member after 70 hours. Judgment is that the volume change rate absolute value before and after the test is ± 20% or more is rejected (x), the case of ± 10% or more and within ± 20% is borderline (△), and the case is within ± 10% (○).

Claims (3)

Sulfur content is 800 mass ppm or less, 1-ring naphthene content is 10 volume% or more, 1-ring aromatic content is 20 volume% or less, 90% distillation temperature is 280 ° C. or more and 350 ° C. or less, and 80 Fatty acid alkyl ester (A) selected from hydrolyzed refined oil having a difference between% distillation temperature and 20% distillation temperature of 50 ° C. or higher and 150 ° C. or lower selected from myristic acid alkyl ester, palmitic acid alkyl ester and stearic acid alkyl ester Any one or more of fatty acid alkyl ester (B) selected from lauric acid alkyl ester, oleic acid alkyl ester, linoleic acid alkyl ester and linolenic acid alkyl ester, Total mass content of alkyl ester (A) / mass content of fatty acid alkyl ester (B) Fatty acid alkyl ester mixture having a total sum of 0.1 or more and 2.0 or less, an average molecular weight of 500 or less, a total acid value of 1.0 mgKOH / g or less, and a sulfur content of 5 mass ppm or less. JIS No. 1 characterized in that the volume modulus of elasticity is 1350 MPa or more and 1550 MPa or less, and the total insoluble matter after the oxidation stability test is 2.0 mg / 100 mL or less. A heavy oil composition satisfying heavy oil standards.
RBDF = (− 6 × C × FAME + HDS × (2 × PA + PN)) / 100
0 ≦ RBDF ≦ 10
RBDF: BDF index
C: Sum of mass content of fatty acid alkyl ester (A) / fatty acid alkyl
Sum of mass content of ruester (B) FAME: Fatty acid alkyl ester mixture content (volume%)
HDS: Hydrorefined oil content (volume%)
PA: Aromatic content of 2 or more rings in hydrorefined oil (volume%)
PN: Content of naphthene in two or more rings in hydrorefined oil (volume%) 2. A heavy oil according to claim 1, having a density at 15 ° C. of 800 kg / m ³ or more and 850 kg / m ³ or less, a cetane number of 40 or more, and an HFRR wear scar diameter (WS 1.4) of 410 μm or less. Composition.   3. A heavy oil composition according to claim 1 or 2, wherein a mixture of fatty acid alkyl esters using vegetable oil as a raw material is blended, and the water content is 800 ppm by volume or less.