JP2006063232A - Gas oil composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a gas oil composition that is a gas oil composition having a relatively large amount of wax precipitation at a low temperature in areas and months in which especially gas oil of JIS guide line of 2 is preferably used in low-sulfur gas oil having ≤10 mass ppm sulfur content, causes no filter clogging at a low temperature and has excellent normal-temperature startability and high fuel consumption. <P>SOLUTION: The gas oil composition comprises 5-50 vol.% based on the total of the gas oil composition of hydrocracking oil having ≥0.82g/cm<SP>3</SP>density at 15°C, -40.0 to 0.0 °C slow-cooling cloud point, ≤100 mass ppm sulfur content, ≤15 mass % normal paraffin content, ≥25 vol.% aromatic component and 90% distillation temperature of 270°C-380°C and has ≥0.82g/cm<SP>3</SP>density at 15°C, 2.5-6.0mm<SP>2</SP>/s kinematic viscosity at 30°C, ≤10 mass ppm sulfur content, -10.0 to 0.0 °C slow-cooling cloud point, ≤ -5 °C cold filter plugging point, ≥50 °C flash point, ≤2.5 mass % wax amount at -10°C and ≤-5°C modified cold filter plugging point. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a low sulfur gas oil composition having a sulfur content of 10 mass ppm or less, which has good low temperature performance, normal temperature performance and high fuel consumption rate (fuel consumption) in a diesel vehicle.

In recent years, from the environmental point of view, the emission of environmental pollutants such as PM (particulate matter), NOx (nitrogen oxide), HC (hydrocarbon), CO (carbon monoxide) in exhaust gas has been greatly increased in diesel vehicles. Reduction is required. For this purpose, the improvement of the engine and the refinement of fuel injection control, as well as the purification of exhaust gas from diesel vehicles by adopting post-treatment devices such as oxidation catalyst, NOx reduction catalyst, DPF (diesel particulate filter), etc. are being promoted. (For example, refer nonpatent literature 1.). On the other hand, in order to effectively demonstrate the capabilities of these aftertreatment devices and maintain durability, diesel oil is required to further reduce the sulfur content (see, for example, Non-Patent Document 2).
Matsuo Shigeru, Present status and future of diesel engines, "Automotive technology", 2003, No. 57 (1), p. 41-46 “The future of vehicle emission reduction measures”, Ministry of the Environment Central Environment Council, Air Environment Committee, Seventh Report, 2003

In order to reduce the sulfur content of light oil, it is effective to reduce the light temperature within the distillation temperature range of the straight-run light oil base material in order to ensure the life of the desulfurization catalyst. However, the lighter narrowing of the base material increases the wax precipitation rate when the temperature is lowered. That is, when the temperature is lowered, the wax is deposited at a stretch.
Moreover, in order to reduce the sulfur content of straight-run gas oil, generally a high degree of hydrorefining treatment is necessary. However, as the hydrogenation of the substrate proceeds, the low-temperature fluidity tends to deteriorate.
Furthermore, in order to produce a low sulfur gas oil, blending of a cracked base material having a relatively high sulfur content (such as a gas oil fraction (MHC-GO) obtained from a mild hydrocracking apparatus) is limited. In general, the cracking base material is excellent in low-temperature fluidity. Therefore, if the blending amount of the cracking base material in light oil is limited to reduce sulfur, the low-temperature fluidity of the light oil may be deteriorated.

On the other hand, in a diesel vehicle, the fuel injection system control has been improved in accuracy in order to make the functions of the aftertreatment device more effective. When the injection system becomes precise, it is necessary to remove finer dust in the fuel, and therefore a fine filter is provided. Such fine filters tend to be clogged easily due to the wax precipitated from the light oil at low temperatures.
In addition, in diesel vehicles that perform such precise injection control, the fuel injection pressure is increased to prevent exhaust gas, and as the fuel injection pressure increases, the amount of fuel that passes through the filter increases, There is a possibility that filter clogging is more likely to occur due to a wax component precipitated from light oil at a low temperature.
Therefore, it is necessary to control the amount of wax in light oil at low temperature in order to prevent filter clogging at low temperature in a combination of low sulfur gas oil and a diesel vehicle that performs post-treatment device and performs more precise injection control. .

  JIS K2204 “Diesel” classifies diesel oil into five grades of No. 1, 1, 2, 3 and No. 3 based on low temperature fluidity, etc. Seasonal usage guidelines have been established. The guidelines state that it is desirable to use No. 2 diesel oil when the regional and monthly minimum temperatures are -10 ° C. However, in the combination of low-sulfur diesel oil and a diesel vehicle with more precise injection control equipped with an aftertreatment device, the minimum temperature is -10 ° C even if the standard of JIS No. 2 diesel oil is satisfied. In some cases, there is a concern of causing filter clogging.

In addition, since diesel vehicles are mobiles and generally have a certain period of time from when diesel oil is produced until it is refueled and used up, diesel oil has low temperature fluidity at the lowest temperature at which it is used. At the same time, it is required that it can be used without problems in practical performance even in an environment of higher temperature than it can be used.
In order to control the amount of wax in light oil at low temperature, the kerosene fraction is usually mixed with the light oil fraction. However, when a kerosene fraction is mixed in a large amount with a light oil fraction, there may be a problem in startability at room temperature due to a decrease in flash point and kinematic viscosity. Moreover, the problem that a fuel consumption deteriorates by a density fall arises.

  The present invention is a light oil composition that has a relatively large amount of wax precipitation at low temperatures especially in low sulfur gas oil having a sulfur content of 10 mass ppm or less, particularly in an area where it is desirable to use JIS guideline No. 2 gas oil. However, the present invention provides a light oil composition that does not cause filter clogging at a low temperature, has good room temperature startability, and high fuel efficiency.

  As a result of intensive studies, the present inventors have found that a light oil composition that simultaneously satisfies all of the specific properties defined below can solve the above problems, and has completed the present invention.

That is, in the present invention, the density at 15 ° C. is 0.82 g / cm ³ or more, the slow cooling cloud point is −40.0 to 0.0 ° C., the sulfur content is 100 mass ppm or less, and the normal paraffin content is 15 mass% or less. The hydrocracked oil having an aromatic content of 25% by volume or more and a 90% distillation temperature of 270 ° C. to 380 ° C. is contained in an amount of 5 to 50% by volume based on the total amount of the light oil composition, and the density at 15 ° C. is 0.82 g / cm ³ or more, kinematic viscosity at 30 ° C. of 2.5 to 6.0 mm ² / s, sulfur content of 10 mass ppm or less, slow cooling cloud point of −10.0 to 0.0 ° C., clogging point of −5 ° C. The following relates to a light oil composition having a flash point of 50 ° C. or more, a wax amount at −10 ° C. of 2.5% by mass or less, and a corrected clogging point of −5 ° C. or less.

  The present invention further relates to the light oil composition as described above, further comprising 50 to 500 mg / L of the low temperature fluidity improver and / or 25 to 500 mg / L of the lubricity improver.

Hereinafter, the contents of the present invention will be described in more detail.
In the present invention, the density at 15 ° C. is 0.82 g / cm ³ or more, the slow cooling cloud point is −40.0 to 0.0 ° C., the sulfur content is 100 mass ppm or less, the normal paraffin content is 15 mass% or less, It is necessary to use hydrocracked oil having an aromatic content of 25% by volume or more and a 90% distillation temperature of 270 ° C. to 380 ° C.

The hydrocracked oil according to the present invention is a heavy feed oil such as atmospheric residual oil, vacuum residual oil, etc., passed through a catalyst having a hydrogenation function under high-temperature and high-pressure hydrogen conditions. A light oil fraction obtained by denitrification or the like, for example, a light oil fraction obtained from a heavy oil direct desulfurization apparatus is preferable. In the heavy oil direct desulfurization apparatus, the reaction is carried out at a high temperature, so that gas, naphtha, kerosene, and light oil fractions are obtained by decomposing part of the raw material oil. Compared to other devices, due to high temperature, high pressure, and low liquid space velocity, the sulfur content of the light oil fraction obtained is obtained from other cracking base materials such as mild hydrocracking equipment and fluid catalytic cracking equipment. Sulfur content is low compared to min.
In addition, as a cracking base material with a low sulfur content, there is a gas oil fraction obtained from a hydrocracking device for vacuum gas oil, but a gas oil fraction obtained from a heavy oil direct desulfurization device has a normal paraffin content compared to that. And cloudy point is low. This is because the hydrogenation function and isomerization ability of the catalyst used are low.

Although the above-mentioned high temperature and high pressure hydrogen conditions are not particularly limited, generally, the hydrogen partial pressure is preferably 10 MPa or more, more preferably 14 MPa or more, further preferably 17 MPa or more, and most preferably 19 MPa or more. The upper limit is not particularly limited, but is preferably 25 MPa or less from the viewpoint of pressure resistance of the reactor.
The reaction temperature is preferably 340 ° C or higher, more preferably 360 ° C or higher, further preferably 370 ° C or higher, and most preferably 380 ° C or higher. Although an upper limit is not specifically limited, From a heat resistant viewpoint of a reactor, 420 degrees C or less is preferable.
Furthermore, the liquid space velocity is preferably 2 / h or less, more preferably 1 / h or less, and most preferably 0.5 / h or less. The lower limit is not particularly limited, but is preferably 0.1 / h or more from the viewpoint of drift.

  The above-mentioned catalyst having a hydrogenation function is not particularly limited, and examples thereof include those using a combination of two or three kinds of metals such as Ni, Co, Mo, W, Pd, and Pt. Specifically, catalysts such as Co—Mo, Ni—Mo, Ni—Co—Mo, and Ni—W can be preferably used. Among them, from the viewpoint of versatility, Co—Mo, Ni— A Mo-based catalyst is more preferable.

The density at 15 ° C. of the hydrocracked oil according to the present invention is required to be 0.82 g / cm ³ or more, preferably from the viewpoint of easily obtaining the light oil composition of the present invention having a predetermined property. 0.83 g / cm ³ or more, more preferably 0.84 g / cm ³ or more.
Here, the density at 15 ° C. means a value measured according to JIS K2249 “Crude oil and petroleum products—density test method and density / mass / capacity conversion table”.

The slow cooling cloud point of the hydrocracked oil according to the present invention needs to be −40.0 to 0.0 ° C. as described above. When the slow-cooling cloud point is higher than 0.0 ° C., it is not preferable in terms of the solubility of the filter-attached wax of the light oil composition of the present invention, and when it is lower than −40.0 ° C., the low-temperature fluidity of the light oil composition of the present invention is low. Since the CFPP lowering ability by an improver becomes insufficient, it is not preferable. In addition, from the viewpoint of solubility of the filter-attached wax, the slow cooling cloud point is preferably −2 ° C. or lower, more preferably −6 ° C. or lower, and most preferably −10 ° C. or lower.
Here, the slow cooling cloud point is obtained by slowly cooling at a temperature of 0.5 ° C./min until a cloud point is detected from a temperature 10 ° C. or more higher than the cloud point, and detecting in units of 0.1 ° C. It is a cloudy point. The method of detecting the slow cooling cloud point is that the sample is irradiated with light, and the reflected light on the aluminum surface at the bottom of the sample container is reduced by a predetermined amount (reflected light of light irradiated from a height of 3 mm from the bottom of the sample liquid with a thickness of 15 mm). Is the slow cooling cloud point.

The sulfur content of the hydrocracked oil according to the present invention is required to be 100 mass ppm or less. If the sulfur content is more than 100 ppm by mass, the properties defined in the light oil composition of the present invention may not be satisfied, which is not preferable. In addition, 70 mass ppm or less is preferable, as for a sulfur content, 50 mass ppm or less is more preferable, and 30 mass ppm or less is further more preferable.
In addition, the sulfur content here means the content of the sulfur content measured by JIS K2541 “Sulfur content test method”.

The normal paraffin content of the hydrocracked oil according to the present invention needs to be 15% by mass or less, preferably 13% by mass or less, and more preferably 11% by mass or less. When the normal paraffin content exceeds 15% by mass, it is not preferable in terms of an increase in precipitated wax of the light oil composition.
The normal paraffin content mentioned here is a content quantified from a gas chromatograph that is equipped with a nonpolar column and an FID (flame ionization detector) and is operated with a predetermined temperature program. What is a gas chromatograph? It is an analytical technique for separating and quantitatively analyzing each composition by utilizing the physical properties (boiling point, polarity, etc.) of each composition in the sample.

The aromatic content of the hydrocracked oil according to the present invention needs to be 25% by volume or more, and in order that the light oil composition of the present invention has good fuel consumption, 30% by volume or more is preferable, and 40% by volume. % Or more is more preferable. On the other hand, from the viewpoint of preventing an increase in PM discharged from the engine, 60% by volume or less is preferable, and 50% by volume or less is more preferable.
The aromatic content herein means a value measured by the Petroleum Institute Standard JPI-5S-49-97 “Hydrocarbon Type Test Method—High Performance Liquid Chromatograph Method” issued by the Japan Petroleum Institute. To do.

  The 90% distillation temperature (T90) of the hydrocracked oil according to the present invention is required to be 270 ° C. to 380 ° C., and from the viewpoint of securing CFPP lowering ability and fuel consumption by the low temperature fluidity improver. The above is preferable, and 290 ° C. or higher is more preferable. On the other hand, from the viewpoint of suppressing an increase in PM discharged from the engine, the temperature is preferably 360 ° C. or lower, more preferably 340 ° C. or lower, and further preferably 320 ° C. or lower. In addition, 90% distillation temperature (T90) here means the value measured by JIS K2254 "petroleum product-distillation test method-atmospheric pressure distillation test method".

  The light oil composition in the present invention needs to contain 5 to 50% by volume, preferably 10 to 50% by volume, of the specific hydrocracked oil based on the total amount of the light oil composition. When the content of the hydrocracked oil is outside the above range, a gas oil composition having a relatively large amount of precipitated wax at low temperatures may cause clogging of the filter at low temperatures, and good startability at normal temperature. It is not preferable because fuel consumption cannot be achieved.

The light oil composition of the present invention comprises 5 to 50% by volume of the hydrocracked oil described above and 50 to 95% by volume of another constituent base material.
As other constituent base materials, various light oil base materials, kerosene base materials, synthetic light oils, synthetic kerosene and the like can be used as long as the fuel properties necessary for the light oil composition of the present invention are satisfied. Moreover, these can also mix | blend 2 or more types.
As such a light oil base or kerosene base, specifically, straight run diesel oil / kerosene obtained from crude oil atmospheric distillation equipment, straight run heavy oil or residual oil obtained from atmospheric distillation equipment is decompressed. Reduced gas oil / kerosene obtained by treating with a distillation unit, hydrorefined gas oil / kerosene obtained by hydrotreating the above-mentioned gas oil with a hydrorefining device according to the sulfur content. Hydrodesulfurized gas oil / kerosene obtained by hydrodesulfurization in stages or multistages, hydrocracked gas oil / kerosene obtained by hydrocracking the above various light oil base materials, and the like can be used.
Synthetic light oil and synthetic kerosene mean synthetic light oil and synthetic kerosene obtained by chemically synthesizing natural gas, asphalt, coal and the like. Chemical synthesis methods include indirect liquefaction method and direct liquefaction method, and typical synthesis methods include Fischer-Trops synthesis method, but the synthetic light oil used in the present invention is limited by these production methods. is not.

The density at 15 ° C. of the light oil composition of the present invention needs to be 0.82 g / cm ³ or more. When the density of the light oil composition is less than 0.82 g / cm ³ , the fuel consumption, engine output, startability at high temperature, and stability of engine rotation at idling deteriorate, which is not preferable. Such reasons, preferably 0.825 g / cm ³ or more, 0.83 g / cm ³ or more is more preferable.
Here, the density at 15 ° C. means a value measured according to JIS K2249 “Crude oil and petroleum products—density test method and density / mass / capacity conversion table”.

The kinematic viscosity at 30 ° C. of the light oil composition of the present invention needs to be 2.5 to 6.0 mm ² / s. When the kinematic viscosity at 30 ° C. is less than 2.5 mm ² / s, there is a possibility of starting failure or unstable engine rotation during idling when used at a relatively high temperature. In addition, there may be a problem in the durability of the fuel injection pump. From the viewpoint of ensuring startability at high temperatures, stability of engine rotation during idling, and ensuring durability of the fuel injection pump, the kinematic viscosity at 30 ° C. is preferably 2.8 mm ² / s or more, and 3.0 mm ² / s or more. More preferred. Moreover, since kinematic smoke will increase when dynamic viscosity in 30 degreeC becomes larger than 6.0 mm < ² > / s, it is unpreferable. From the viewpoint of preventing increase in black smoke, the kinematic viscosity at 30 ° C. is preferably 5.8 mm ² / s or less, more preferably 5.6 mm ² / s or less, and 5.5 mm ² / s or less. Most preferred.
Here, the kinematic viscosity at 30 ° C. means a value measured by JIS K2283 “Crude oil and petroleum products—Kinematic viscosity test method and viscosity index calculation method”.

The sulfur content of the light oil composition of the present invention needs to be 10 mass ppm or less. When the sulfur content in the light oil composition is more than 10 mass ppm, the exhaust gas purification performance of the aftertreatment device of the diesel vehicle is deteriorated, which is not preferable. In addition, 5 mass ppm or less is preferable from a viewpoint of the exhaust gas purification performance of the post-processing apparatus of a diesel vehicle, and, as for a sulfur content, 1 mass ppm or less is more preferable.
In addition, the sulfur content here means the content of the sulfur content measured by JIS K2541 “Sulfur content test method”.

The slow cooling cloud point of the light oil composition of the present invention is required to be -10.0 to 0.0 ° C. When the slow-cooling cloud point is higher than 0.0 ° C, it is not preferable in terms of the solubility of the filter-attached wax, and when it is lower than -10.0 ° C, it is not preferable because the CFPP lowering ability by the low-temperature fluidity improver becomes insufficient. .
In addition, from the viewpoint of solubility of the filter-attached wax, the slow cooling cloud point is preferably −2.0 ° C. or less, more preferably −4.0 ° C. or less, and −6.0 ° C. or less. Most preferred.

The clogging point of the light oil composition of the present invention is required to be −5 ° C. or less, preferably −8 ° C. or less, and −10 ° C. or less from the viewpoint of preventing filter blockage of a diesel vehicle. More preferably.
The clogging point here means a value measured according to JIS K2288 "Petroleum product-light oil-clogging point test method".

The flash point of the light oil composition of the present invention is required to be 50 ° C. or higher, and preferably 60 ° C. or higher, from the viewpoint of ensuring safety during handling.
The flash point here means a value measured by JIS K2265 “Crude oil and petroleum product flash point test method”.

The amount of wax at −10 ° C. of the light oil composition of the present invention is required to be 2.5% by mass or less and preferably 2.4% by mass or less from the viewpoint of preventing filter blockage of a diesel vehicle. As used herein, the amount of wax at −10 ° C. means an amount measured by a low-temperature differential scanning calorimeter. The low-temperature differential scanning calorimeter is based on the temperature difference between the sample and the reference material that occurs when the sample changes phase at a certain temperature while cooling the temperature of the sample part composed of the sample and the reference material according to a certain program. This is an apparatus for quantifying the amount of phase change in a sample. The measurement of the wax amount a (unit: mass%) at −10 ° C. with a low-temperature differential scanning calorimeter is carried out by setting a sample of a predetermined amount m (unit: mg) on a low-temperature differential scanning calorimeter and −3 ° C./min. When it is cooled at the rate of temperature decrease, the amount of heat generated by the wax precipitation is measured. Then, the total heat generation amount b from the heat generation start temperature to −10 ° C. (unit: mJ, 0 when the heat generation start temperature is lower than −10 ° C.) is divided by the heat generation amount per unit wax amount (188 mJ / mg). This is the value obtained. Specifically, it is obtained by the following formula.
a (mass%) = (b ÷ 188) ÷ m × 100

The corrected clogging point of the light oil composition of the present invention is required to be −5 ° C. or less, preferably −8 ° C. or less, from the viewpoint of preventing filter blockage in a diesel vehicle.
In addition, the correction clogging point as used in the field of this invention means the value measured by the correction method 4 as described in the description of the Petroleum Institute method JPI-5S-47-96 “Low temperature fluidity test method of heavy oil A”.

The pour point of the light oil composition of the present invention is preferably −7.5 ° C. or less, more preferably −10.0 ° C. or less, from the viewpoint of securing fluidity in the fuel line, and −15. Most preferably, it is 0 ° C. or lower.
The pour point here means a value measured by JIS K2269 “Pour point of crude oil and petroleum products and cloud point test method of petroleum products”.

The cetane index of the light oil composition of the present invention is preferably 45.0 or more, more preferably 48.0 or more, and most preferably 50.0 or more from the viewpoint of engine ignitability.
The cetane index here means a value calculated according to JIS K2280 “Petroleum products-fuel oil-octane number and cetane number test method and cetane index calculation method”.

In the light oil composition of the present invention, the distillation properties are not particularly limited, but are preferably as follows.
Initial boiling point (IBP): 140-230 ° C
10% distillation temperature (T10): 165 to 260 ° C
50% distillation temperature (T50): 240-310 ° C
90% collection temperature (T90): 300-350 ° C
95% distillation temperature (T95): 305-365 ° C
End point (EP): 310-380 ° C
Here, the distillation property means a value measured according to JIS K2254 “Petroleum product-distillation test method”.

  When the IBP of the light oil composition of the present invention is too low, there is a concern that some light fractions are vaporized, the spray range is too wide, and HC entrained in the exhaust gas as an unburned component increases. From the viewpoint of ensuring startability at high temperatures and stability of engine rotation during idling, IBP is preferably 140 ° C or higher, more preferably 150 ° C or higher, more preferably 155 ° C or higher, and most preferably 160 ° C or higher. is there. On the other hand, when IBP is too high, there is a possibility of causing problems in low temperature startability and low temperature drivability, so IBP is preferably 230 ° C. or lower, more preferably 220 ° C. or lower, most preferably 215 ° C. or lower. It is.

  When T10 of the light oil composition of the present invention is too low, there is a concern that HC accompanying the exhaust gas may increase, as in the case of IBP being too low, and startability at high temperatures, stability of engine rotation at idling From the viewpoint of securing the property, T10 is preferably 165 ° C. or higher, more preferably 170 ° C. or higher, and most preferably 175 ° C. or higher. On the other hand, T10 is preferably 260 ° C. or lower, more preferably 255 ° C. or lower, and most preferably 250 ° C. or lower because T10 is too high, which may cause problems in low temperature startability and low temperature drivability. It is.

  T50 of the light oil composition of the present invention is preferably 240 ° C. or higher, more preferably 250 ° C. or higher, from the viewpoints of fuel efficiency, engine output, startability at high temperatures, and stability of engine rotation during idling. Preferably it is 260 degreeC or more. On the other hand, from the viewpoint of preventing an increase in PM discharged from the engine, T50 is preferably 310 ° C. or lower, more preferably 300 ° C. or lower, and most preferably 295 ° C. or lower.

  T90 of the light oil composition of the present invention is preferably 350 ° C. or less, more preferably 345 ° C. or less, and most preferably 340 ° C. or less from the viewpoint of preventing an increase in particulate matter (PM) discharged from the engine. is there. On the other hand, the lower limit is preferably 90 ° C. or higher from the viewpoint of securing CFPP lowering ability by a low temperature fluidity improver, starting performance at high temperature, ensuring stability of engine rotation at idling, and fuel consumption, and 310 ° C. More preferably, it is more preferably 315 ° C. or higher.

  T95 of the light oil composition of the present invention is preferably 305 ° C. or higher from the viewpoints of securing CFPP lowering ability by a low temperature fluidity improver, starting performance at high temperature, ensuring stability of engine rotation at idling, and fuel consumption. More preferably, it is 315 degreeC or more, Most preferably, it is 320 degreeC or more. On the other hand, from the viewpoint of preventing increase in PM discharged from the engine, T95 is preferably 365 ° C. or less, more preferably 360 ° C. or less, further preferably 355 ° C. or less, even more preferably 350 ° C. or less, and most preferably It is 345 degrees C or less.

  The EP of the light oil composition of the present invention is preferably 310 ° C. or higher from the viewpoints of securing CFPP lowering ability by a low temperature fluidity improver, starting performance at high temperature, ensuring engine rotation stability at idling, and fuel consumption. More preferably, it is 320 degreeC or more, Most preferably, it is 325 degreeC or more. On the other hand, from the viewpoint of preventing increase in PM discharged from the engine, EP is preferably 380 ° C. or lower, more preferably 375 ° C. or lower, further preferably 370 ° C. or lower, and most preferably 365 ° C. or lower.

The WS1.4 value of HFRR of the light oil composition of the present invention is preferably 500 μm or less, more preferably 460 μm or less, and further preferably 420 μm or less from the viewpoint of ensuring the lubricity of the fuel injection pump. Preferably, it is most preferably 400 μm or less.
The WS1.4 value of HFRR here means a value measured by the Petroleum Institute Standard JPI-5S-50-98 “Light Oil-Lubricity Test Method” issued by the Japan Petroleum Institute.

The light oil composition of the present invention preferably contains a low-temperature fluidity improver from the viewpoint of preventing filter blockage in a diesel vehicle.
The type of the low-temperature fluidity improver is not particularly limited. For example, ethylene-unsaturated ester copolymer represented by ethylene-vinyl acetate copolymer, alkenyl succinic acid amide, dibehenic acid ester of polyethylene glycol Linear compounds such as phthalic acid, ethylenediaminetetraacetic acid, nitriloacetic acid and the like, or polar nitrogen compounds consisting of reaction products of hydrocarbyl-substituted amines, alkyl fumarate or alkyl itaconate-unsaturated esters One kind or two or more kinds of low-temperature fluidity improvers such as a comb polymer made of a copolymer can be used. Among these, from the viewpoints of versatility and low-temperature practical performance improvement, an ethylene-vinyl acetate copolymer additive and a polar nitrogen compound can be preferably used. When the low temperature fluidity improver is added, the addition amount is preferably 50 to 500 mg / L, and particularly preferably 100 to 500 mg / L. In addition, since a commercial product referred to as a low temperature fluidity improver may be diluted with an appropriate solvent for an active ingredient that contributes to low temperature fluidity, such a commercial product is used as the light oil composition of the present invention. In the case of adding, the above-mentioned addition amount means the addition amount as an active ingredient.

Moreover, it is preferable that the light oil composition of this invention contains a lubricity improvement agent from a viewpoint of ensuring lubricity in an injection pump.
The type of the lubricity improver is not particularly limited, but one or more of the lubricity improvers such as ester, carboxylic acid, alcohol, phenol, and amine can be used. . Among these, from the viewpoint of versatility, it is preferable to use an ester-based or carboxylic acid-based lubricity improver. Furthermore, an ester-based lubricity improver is preferable from the viewpoint that the additive effect on the added concentration hardly reaches saturation and the WS1.4 value of HFRR can be further reduced, and the initial responsiveness of the added effect on the added concentration is high, and the lubricity improver Carboxylic acid type lubricity improvers are preferred from the viewpoint that the amount of addition of can be reduced.

Examples of the ester-based lubricity improver include glycerin carboxylic acid ester and the like. 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. . Examples of the carboxylic acid-based lubricity improver include linoleic acid, oleic acid, salicylic acid, palmitic acid, myristic acid, hexadecenoic acid, and the like, and one or more of these can be used arbitrarily. is there.
If the low-temperature fluidity improver has a lubricity improving effect, the use of only the low-temperature fluidity improver can improve the lubricity, but the low-temperature fluidity improver and the lubricity improver are combined. As a result, the lubricity can be further improved.

  When the lubricity improver is added, the addition amount is preferably 25 to 500 mg / L, more preferably 25 to 300 mg / L or less, and further preferably 25 to 200 mg / L or less. In particular, it is preferable to add a lubricity improver so that the WS1.4 value of HFRR is preferably 460 μm or less, more preferably 420 μm or less, and most preferably 400 μm or less. In addition, as for the commercial item called a lubricity improver, the active ingredient which contributes to lubricity is usually obtained in the state diluted with a suitable solvent. In the case where such a commercial product is added to the light oil composition of the present invention, the above addition amount means the addition amount as an active ingredient.

  In the light oil composition of the present invention, other optional additives other than the low temperature fluidity improver and the lubricity improver can be appropriately blended without departing from the properties defined in the present invention. These additives include cetane number improvers such as nitrate esters and organic peroxides typified by 2-ethylhexyl nitrate, alkenyl succinic acid derivatives, detergents such as amine salts of carboxylic acids, phenols, Antioxidants such as amines, metal deactivators such as salicylidene derivatives, anti-icing agents such as polyglycol ethers, corrosion inhibitors such as aliphatic amines and alkenyl succinates, anionic, cationic and amphoteric interfaces Examples thereof include an antistatic agent such as an activator, a colorant such as an azo dye, a silicon-based antifoaming agent, and the like. These other additives can be added singly or in combination of several kinds. Although the addition amount is also arbitrary, the total amount of other additives is usually 0.5% by mass or less, preferably 0.2% by mass or less, based on the total amount of the light oil composition. In addition, the addition amount whole quantity here means the addition amount as an active ingredient of an additive.

  The light oil composition of the present invention has good low-temperature performance, normal-temperature performance, and high fuel efficiency despite the low sulfur content of 10 ppm by mass or less.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[Examples 1-8 and Comparative Examples 1-4]
Hydrocracked diesel oils 1 to 3 obtained by hydrocracking the feedstock oil of Table 1 under the conditions shown in Table 2, and hydrogen obtained by hydrodesulfurization treatment of the feedstock oil of Table 1 under the conditions shown in Table 2 By mixing hydrodesulfurized diesel oil 1-2 and hydrodesulfurized kerosene at a blending ratio shown in Table 3, and adding low temperature fluidity improver and lubricity improver to the concentrations shown in Table 3, the present invention A light oil composition (Examples 1 to 8) and a comparative light oil composition (Comparative Examples 1 to 4) were prepared. Properties of these light oil compositions are shown in Table 4.

The properties of the base material and the light oil composition were measured by the following analytical methods.
The sulfur content was measured according to JIS K2541 “Sulfur content test method”.
The density was measured according to JIS K2249 “Crude oil and petroleum products—Density test method and density / mass / capacity conversion table”.
Distillation properties were measured according to JIS K2254 “Petroleum products—Distillation test method”.
The slow cooling cloud point is the cloud point detected as described above at a rate of 0.5 ° C./min.
The normal paraffin content was quantified from the gas chromatograph as described above.
The aromatic content was measured by the Petroleum Institute Standard JPI-5S-49-97 “Hydrocarbon Type Test Method—High Performance Liquid Chromatograph Method”.
The pour point was measured according to JIS K2269 “Pour point of crude oil and petroleum products and cloud point test method of petroleum products”.
The clogging point was measured in accordance with JIS K2288 “Petroleum products—light oil—clogging point test method”.
The cetane index was measured according to JIS K2280 “Petroleum products—fuel oil—octane number and cetane number test method and cetane index calculation method”.
The kinematic viscosity (30 ° C.) refers to the kinematic viscosity at 30 ° C. measured by JIS K2283 “Crude oil and petroleum products—Kinematic viscosity test method and viscosity index calculation method”.
WSFR 1.4 of HFRR was measured according to Petroleum Institute Standard JPI-5S-50-98 “Light Oil-Lubricity Test Method”.
The flash point was measured according to JIS K2265 “Crude oil and petroleum product flash point test method”.
The amount of wax at −10 ° C. was quantified with a low-temperature differential scanning calorimeter as described above.
The corrected clogging point was measured by the correction method 4 described in the description of JPI-5S-47-96 “A low temperature fluidity test method for heavy oil A”.

Next, the various tests shown below were performed on the light oil compositions of Examples 1 to 8 and Comparative Examples 1 to 4.
(Low-temperature vehicle test)
On a chassis dynamometer capable of controlling the ambient temperature, at room temperature, (1) flush the fuel system of the test diesel car with the evaluation fuel, (2) extract the flushing fuel, and (3) a new main filter (4) Insert the specified amount of fuel to be evaluated into the fuel tank (1/2 of the fuel tank capacity of the vehicle under test). Thereafter, (5) the ambient temperature is rapidly cooled from room temperature to 5 ° C., (6) held at 5 ° C. for 1 hour, (7) slowly cooled to −10 ° C. at a cooling rate of 1 ° C./h, ( 8) After running at -10 ° C for 1 hour, start running test. The driving test consists of (9) engine start, (10) idling for 5 minutes, (11) acceleration to 50 km / h, and (12) driving for 1 hour at 50 km / h. judge. If there was no problem with engine start, idling, and acceleration, and 50 km / h traveling could be maintained over the entire traveling, it was judged as good (◎). In the first cranking, minor problems occurred, such as when the engine could not be started or when the vehicle speed decreased temporarily during driving, but then recovered. . It was determined that the engine could not be started (when cranking for 10 seconds was not started even after being repeated 5 times at 30-second intervals). The following two diesel vehicles A and B were used in the low-temperature actual vehicle test.

Vehicle A is a diesel truck that conforms to short-term regulations and is equipped with a PM reduction device designated by Tokyo. The specifications are as follows.
(Vehicle A specifications)
Maximum loading capacity: 2t
Engine type: Inline 4-cylinder diesel
Engine displacement: 4.3L
Fuel injection pump: In-line type Applicable regulations: Compliant with short-term exhaust gas regulations (base vehicle)
Exhaust gas aftertreatment device: PM reduction device designated by Tokyo (conforming to Category 4)

The vehicle B is a sports utility vehicle conforming to long-term regulations. The specifications are as follows.
(Vehicle B specifications)
Engine type: Supercharged in-line 4-cylinder diesel with intercooler Displacement: 3.0L
Fuel injection system: Common rail method Conformity regulation: Long-term exhaust gas regulation conformity Exhaust gas aftertreatment device: Oxidation catalyst

(High temperature startability test)
In a room where the environmental temperature can be controlled, 15 L of evaluation fuel is supplied to the test vehicle, and after setting the environmental temperature to 30 ° C., the engine is started and held by idling. When the fuel injection pump outlet temperature of the idling vehicle is stabilized, the engine is stopped and left for 5 minutes, and then the engine is restarted. At this time, when the engine started normally, it passed (◯), and when it did not start, it was rejected (x).

The vehicle C used in the high temperature startability test is a diesel truck of a low-pollution vehicle designated by the seven metropolitan cities that conforms to long-term regulations. The specifications are as follows.
(Vehicle C specifications)
Maximum loading capacity: 4t
Engine type: In-line 6-cylinder engine Engine displacement: 8.2L
Fuel injection pump: High-pressure distribution type Applicable regulations: Long-term exhaust gas regulations (low-pollution vehicles designated by seven prefectures)
Exhaust gas aftertreatment device: oxidation catalyst

(Vehicle fuel consumption test)
Using vehicle B, fuel consumption was measured. The test mode is a transient operation mode that simulates the actual driving shown in FIG. 1, and the fuel consumption is corrected for the fuel volume flow rate consumed during the test mode and replaced with the weight value. Each result was compared and quantified relative to 100 as the result of the test. Accordingly, if the amount of fuel consumption is less than that of Comparative Example 2, the value is less than 100, and if it is greater, the value exceeds 100.

  The results of each test are as shown in Table 4, while the light oil compositions of Comparative Examples 1 to 4 failed either the low-temperature actual vehicle test or the high-temperature startability test using two vehicles. The diesel oil compositions of Examples 1 to 8 passed both the low-temperature actual vehicle test and the high-temperature startability test using two vehicles. Moreover, as a result of the fuel consumption test, the light oil composition of Examples 1 to 8 improved the fuel consumption with respect to the light oil composition of Comparative Example 2.

It is a figure which shows the test mode in a fuel consumption measurement.

Claims (2)

15 Density at ° C. is 0.82 g / cm ³ or more, annealing cloud point -40.0～0.0 ° C., sulfur content 100 ppm by mass or less, normal paraffins content of 15 wt% or less, an aromatic content of 25 volume The hydrocracked oil having a distillation temperature of 270 ° C. to 380 ° C. is contained in an amount of 5 to 50% by volume based on the total amount of the light oil composition, and the density at 15 ° C. is 0.82 g / cm ³ or more at 30 ° C. Kinematic viscosity is 2.5 to 6.0 mm ² / s, sulfur content is 10 mass ppm or less, slow cooling cloud point is −10.0 to 0.0 ° C., clogging point is −5 ° C. or less, and flash point is 50. A gas oil composition having a wax amount at 2.5 ° C. or less at −10 ° C. and a corrected clogging point of −5 ° C. or less.   The gas oil composition according to claim 1, comprising 50 to 500 mg / L of the low temperature fluidity improver and / or 25 to 500 mg / L of the lubricity improver.

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