JP2012031333A - Gas oil composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas oil composition capable of improving fuel cost, while improving exhaust gas characteristic.SOLUTION: In this gas oil composition including a desulfurized gas oil base material obtained by desulfurizing a fraction formed by mixing a straight-run gas oil fraction whose 90% distillation temperature distilled from an atmospheric distillation apparatus is 330-345°C with a catalytically cracked gas oil fraction whose 90% distillation temperature obtained from a fluidized catalytic cracking unit is 320-350°C in a volume proportion of 95:5 to 80:20, (a) a cetane number is 50-60, (b) a 90% distillation temperature is 282-336°C, (c) a 15°C density is 0.832-0.848 g/cm, (d) a flash point is ≥61°C, (e) a 40°C kinematic viscosity is 1.9-4.1 mm/s, (f) a sulfur content is ≤50 mass ppm, (g) a total aromatic amount is ≤30 mass%, (h) a polycyclic aromatic is ≤4.5 mass%, and (i) HFRR is ≤420 μm.

Description

  The present invention relates to a low-sulfur gas oil composition, and more particularly to a gas oil composition having excellent fuel efficiency and excellent engine exhaust gas characteristics.

  It is a social requirement to reduce NOx and particulate matter discharged from diesel engines used for vehicles and generators, etc. In order to reduce particulate matter in diesel oil fuel Therefore, reduction of sulfur content, lightening of distillation properties, reduction of aromatic content, etc. are required. In order to deal with these problems, kerosene is generally used after lightening the distillation properties of the straight-run gas oil (LGO) fraction distilled from the atmospheric distillation apparatus and hydrodesulfurizing the gas oil fraction. Light oil is formulated by blending fractions and the like. However, it is known that the lightening may lower the density and deteriorate the fuel efficiency.

  On the other hand, in order to reduce particulate matter, Diesel Particulate Filter (DPF) has come to be installed as an engine aftertreatment device. The DPF is a device that captures particulate matter discharged from a diesel engine with a filter, and a differential pressure is generated as the particulate matter is captured. In order to eliminate the differential pressure generated by the particulate matter deposition, it is necessary to inject fuel into the DPF, remove the deposited particulate matter, and regenerate the DPF. Thus, since regeneration of the DPF causes deterioration of fuel consumption, it is important to suppress an increase in the differential pressure of the DPF in order to improve fuel consumption characteristics.

  As a diesel light oil composition with low fuel consumption, a diesel light oil composition containing a desulfurized light oil base material obtained by mixing and passing through straight gas light oil and cracked light oil obtained from a cracker through a light oil desulfurizer is proposed. (For example, refer to Patent Document 1). All the examples described in Patent Document 1 reflect the sulfur content regulation value of light oil at the time of filing of the patent application related to Patent Document 1, and the sulfur content is 0.04 to 0.05 mass%. Although it has been reduced, the improvement in fuel efficiency is not sufficient. Furthermore, it is now known that catalysts used in engine aftertreatment devices are poisoned by sulfur oxides produced by the combustion of sulfur in light oil, reducing the function of the catalyst. The minute regulation value is strengthened to 10 mass ppm or less. In a light oil composition obtained from crude oil as a raw material oil, in order to reduce the sulfur content to 10 ppm by mass or less, it is necessary to desulfurize compounds that are difficult to desulfurize (difficult desulfurization substances), and the decomposition function as a desulfurization catalyst The catalyst which has is used. For this reason, for example, in the diesel light oil composition described in Patent Document 1, when it is attempted to reduce the sulfur content to the current sulfur content regulation value, the decomposition reaction also proceeds together with the desulfurization reaction, and the resulting diesel light oil composition is obtained. The density of the fuel cell may further decrease, and the fuel consumption may be further deteriorated.

  In addition, a low sulfur gas oil composition having a sulfur content of 50 mass ppm or less that combines effective reduction of exhaust gas in diesel vehicles and good low-temperature performance has been proposed. For example, in Patent Document 2, in order to improve low-temperature fluidity, hydrocracked diesel oil obtained from a base oil or hydrocracking apparatus having a specific amount of normal paraffin is blended with a light oil base material having specific properties. A low sulfur gas oil composition is described. However, Cited Document 2 does not discuss further improving the fuel saving characteristics in the low sulfur gas oil composition.

  In this way, in diesel engines, it is important to achieve both low emission characteristics and low fuel consumption from the viewpoint of environmental friendliness and economy, and low emissions while satisfying the current sulfur regulations for diesel oil. A light oil composition that achieves both gas characteristics and fuel saving characteristics is desired.

JP-A-8-311462 Japanese Patent Laid-Open No. 2005-220329

  An object of this invention is to provide the light oil composition which improves a fuel consumption, improving an exhaust gas characteristic in such a condition.

  As a result of intensive studies on a technology for reducing exhaust gas discharged from a diesel engine and a technology for improving fuel consumption, the present inventors have found that a straight-run gas oil fraction having a specific distillation property and a catalytic cracking gas oil fraction having a specific distillation property And a desulfurization treatment at a specific ratio, it was found that a light oil composition having a high density but a light distillation property can be produced, and the present invention has been completed.

That is, the present invention
(1) A 90% distillation temperature of 330-345 ° C distillate gas oil distilled from an atmospheric distillation unit and a 90% distillation temperature of 320-350 ° C catalytic cracking gas oil obtained from a fluid catalytic cracking unit A gas oil composition comprising a desulfurized gas oil base material obtained by desulfurizing a mixture of a fraction and a volume ratio of 95: 5 to 80:20,
(A) a cetane number of 50-60,
(B) 90% distillation temperature is 282 to 336 ° C,
(C) 15 degreeC density is 0.832-0.848g / cm < ³ >,
(D) Flash point is 61 ° C or higher,
(E) Kinematic viscosity at 40 ° C. of 1.9 to 4.1 mm ² / s,
(F) Sulfur content is 50 mass ppm or less,
(G) The total aromatic content is 30% by mass or less,
(H) The light oil composition is characterized in that the polycyclic aromatic is 4.5% by mass or less, and (i) the HFRR is 420 μm or less.

  ADVANTAGE OF THE INVENTION According to this invention, the light oil composition suitable as a fuel oil composition for diesel engines used for vehicles, generators, etc. which made the low exhaust gas characteristic and the fuel-saving characteristic compatible can be provided.

The gas oil composition of the present invention has a 90% distillation temperature of 330 to 345 ° C distilled from an atmospheric distillation apparatus and a 90% distillation temperature of 320 to 350 obtained from a fluid catalytic cracking apparatus. A gas oil composition comprising a desulfurized gas oil base material obtained by desulfurizing a mixture of a catalytically cracked gas oil fraction at 0.degree. C. at a volume ratio of 95: 5 to 80:20, and comprising the following (a) to ( The fuel characteristic of i) is provided.
(A) a cetane number of 50-60,
(B) 90% distillation temperature is 282 to 336 ° C,
(C) 15 degreeC density is 0.832-0.848g / cm < ³ >,
(D) Flash point is 61 ° C or higher,
(E) Kinematic viscosity at 40 ° C. of 1.9 to 4.1 mm ² / s,
(F) Sulfur content is 50 mass ppm or less,
(G) The total aromatic content is 30% by mass or less,
(H) Polycyclic aromatic is 4.5 mass% or less, and (i) HFRR is 420 μm or less.

  In the present invention, a straight-run gas oil (LGO) fraction distilled from an atmospheric distillation device whose distillation properties are optimized respectively and a catalytic cracking light oil (LCO) fraction obtained from a fluid catalytic cracking device are in a specific ratio. Then, a desulfurized light oil base material obtained by desulfurization with a hydrodesulfurization apparatus is used. The desulfurized gas oil base material has a low density of 90% and a high density despite being sufficiently lightened. For this reason, by including the desulfurized light oil base material, the light oil composition of the present invention can simultaneously achieve exhaust gas reduction from a diesel engine and fuel efficiency improvement.

Hereinafter, the contents of the present invention will be described in more detail.
In the gas oil composition of the present invention, the 90% distillation temperature of the straight-run gas oil (LGO) fraction distilled from the atmospheric distillation apparatus is 330 to 345 ° C, preferably 332 to 343 ° C. When the 90% distillation temperature is 330 ° C. or higher, the fuel efficiency of the diesel engine can be kept within a favorable range. Further, when the 90% distillation temperature is 345 ° C. or lower, the discharge amount of soot that is a component of the particulate matter discharged from the engine can be reduced. In addition, in this application document, 90% distillation temperature means the value measured based on the rule of ASTM D86.

  In the light oil composition of the present invention, the 90% distillation temperature of the catalytically cracked light oil (LCO) fraction obtained from the fluid catalytic cracker is 320 to 350 ° C, preferably 322 to 348 ° C. When the 90% distillation temperature is 320 ° C. or higher, the fuel efficiency of the diesel engine can be kept within a favorable range. In addition, when the 90% distillation temperature is 350 ° C. or lower, the discharge of soluble organic components (SOF content) composed of soot and high-boiling hydrocarbon components that are components of particulate matter discharged from the engine The amount can be reduced. In addition, in this application document, 90% distillation temperature means the value measured based on the rule of ASTM D86.

  In the light oil composition of the present invention, the blending ratio of the straight-run gas oil (LGO) fraction and the catalytic cracking light oil (LCO) fraction to be desulfurized is 95: 5 to 80:20, preferably 92: 8 to 81:19. It is. Maintaining the fuel efficiency of diesel engines within a good range by setting the blending amount of catalytic cracking light oil (LCO) to the total amount of straight-run gas oil (LGO) fraction and catalytic cracking light oil (LCO) fraction to 5% by mass or more. be able to. Moreover, by setting it as 20 mass% or less, the discharge amount of soot and SOF which are the components of the particulate matter discharged | emitted from an engine can be reduced.

  The desulfurized light oil base material (hereinafter referred to as the desulfurized light oil base material of the present invention) contained in the light oil composition of the present invention is a mixed raw material oil of a straight-run light oil (LGO) fraction and a catalytic cracked light oil (LCO) fraction. It can manufacture by hydrotreating in presence of this. As the catalyst and the hydrotreating method itself, a known catalyst and hydrotreating method can be used.

In the present invention, the catalyst used for the hydrotreating is not particularly limited, and various hydrotreating catalysts can be used. Examples of the catalyst carrier include inorganic compounds such as silica, alumina, zeolite, boria, magnesia, titania, and phosphorous oxide, or a mixture of one or more of these, composite oxides, and the like. Further, as the metal supported on the carrier, a periodic table group 6 metal such as molybdenum or tungsten, or a periodic table group 8 metal such as cobalt, nickel, platinum, rhodium, ruthenium, or the like can be used. It may be used alone or in combination of two or more. Preferred are a cobalt-molybdenum-based hydrogenation catalyst, a nickel-molybdenum-based hydrogenation catalyst, a nickel-cobalt-molybdenum-based hydrogenation catalyst, and a nickel-tungsten-based hydrogenation catalyst.
In addition to the above components, those carrying a third component such as phosphorus, fluorine, boron, zinc, chlorine, sodium, lithium, potassium, rubidium, magnesium, cesium, zirconia can also be used. Further, a chelating organic compound such as citric acid may be included. These chelating organic compounds are more preferably contained in the hydrotreating catalyst in a state of forming a complex with cobalt or nickel.

  By setting the hydrogen pressure higher than the hydrogen partial pressure used in normal hydrodesulfurization as the hydrotreating condition, the desulfurized light oil base material of the present invention can be produced. The hydrogen partial pressure is 2 to 10 MPa, preferably 3 to 8 MPa, and more preferably 5 to 8 MPa. If the hydrogen partial pressure is within the above range, the desulfurization performance can be improved, and the aromatic content of the desulfurized light oil base material can be reduced to a predetermined range.

  Moreover, reaction temperature is 300-400 degreeC, Preferably, it is 320-380 degreeC. When the reaction temperature is within the above range, the desulfurization performance is high, and the aromatic content of the desulfurized light oil base material can be reduced to a predetermined range.

Also, the liquid hourly space velocity 0.3～5Hr ^-1, preferably 0.5～4Hr ^-1, and more preferably from 0.5~3hr ^-1. When the liquid space velocity is within the above range, the contact time between the catalyst and the raw material oil is sufficient, the processing efficiency is improved, the desulfurization reaction is sufficiently performed, and the residual sulfur content of the produced oil is reduced.

The hydrogen / oil ratio is 100 to 600 Nm ³ / kl, preferably 150 to 400 Nm ³ / kl, more preferably 150 to 300 Nm ³ / kl. If the hydrogen / oil ratio is within the above range, the desulfurization reaction proceeds sufficiently, and the processing cost can be reduced without consuming excessive hydrogen.

  The light oil composition of the present invention may contain other light oil fractions other than the desulfurized light oil base within the range satisfying the fuel characteristics (a) to (i). As other gas oil fractions, hydrogenated gas oil fractions obtained by hydrotreating vacuum gas oil obtained by treating atmospheric residue oil obtained by fractionating crude oil with an atmospheric distillation device using a vacuum distillation device , Hydrogenated gas oil fraction obtained by hydrotreating normal pressure residue oil or vacuum residue oil obtained by vacuum distillation equipment, hydrogen obtained by hydrocracking treatment using a heavier fraction than gas oil as a raw material Examples thereof include hydrocracked gas oil and hydrogenated gas oil fraction obtained by hydrotreating animal and vegetable oils.

  The light oil composition of the present invention may further contain a kerosene fraction within the range satisfying the fuel characteristics (a) to (i) above. However, usually, when a kerosene fraction is included, the 90% distillation temperature or 15 ° C. density often falls outside the above range (b) or (c). For this reason, it is preferable that the light oil composition of the present invention does not contain a kerosene fraction.

  In the light oil composition of the present invention, the cetane number is 50 to 60, preferably 52 to 60. If the cetane number is lower than this, the startability of the diesel engine at low temperatures may be lowered, and the CO and HC emissions from the engine may increase. In addition, in this application document, a cetane number means the value measured based on the prescription | regulation of ASTMD613-84.

  In the light oil composition of the present invention, the 90% distillation temperature is 282 to 336 ° C, preferably 300 to 336 ° C, more preferably 320 to 336 ° C. When the 90% distillation temperature is 282 ° C. or higher, the fuel efficiency of the diesel engine can be kept within a favorable range. Moreover, by being 336 degrees C or less, the discharge amount of soot and SOF which are the components of the particulate matter discharged | emitted from an engine can be reduced. In addition, in this application document, 90% distillation temperature means the value measured based on the rule of ASTM D86.

In the light oil composition of the present invention, the density at 15 ° C. is 0.832 to 0.848 g / cm ³ , preferably 0.832 to 0.840 g / cm ³ , more preferably 0.833 to 0.839 g / cm ^3. It is. By having the density within the range, the fuel efficiency of the diesel engine can be kept within a good range, and the amount of soot and SOF that are components of particulate matter discharged from the engine can be reduced. it can. In addition, in this application document, a 15 degreeC density means the value measured based on the prescription | regulation of ASTMD-4052.

  In the light oil composition of the present invention, the flash point is 61 ° C. or higher, preferably 62 ° C. or higher. When the flash point is 61 ° C. or higher, the proportion of light components does not increase too much, and the fuel efficiency of the diesel engine can be kept within a favorable range. In addition, in this application document, a flash point means the value measured based on the prescription | regulation of ASTM D-93.

In the light oil composition of the present invention, the 40 ° C. kinematic viscosity is 1.9 to 4.1 mm ² / s, preferably 2.0 to 3.8 mm ² / s. A kinematic viscosity within this range is preferable because it does not cause a failure in the injection pump of the diesel engine, and prevents an increase in particulate matter discharged from the diesel engine that adversely affects fuel spray. In addition, in this application document, 40 degreeC kinematic viscosity means the value measured based on the prescription | regulation of ASTM D-445.

  In the light oil composition of this invention, a sulfur content is 50 mass ppm or less, Preferably it is 10 mass ppm or less, More preferably, it is 9 mass ppm or less. If the sulfur content is higher than this, the amount of sulfate that is a component of the particulate matter emitted from the engine will increase, which may adversely affect the performance of the exhaust gas aftertreatment device and increase other exhaust gases. . In addition, in this application document, a sulfur content means the value measured based on the prescription | regulation of ASTMD-5453.

  In the light oil composition of the present invention, the total aromatic content is 30% by mass or less, preferably 27% by mass or less, and the polycyclic aromatic content is 4.5% by mass or less, preferably 3.1% by mass or less. is there. Although there is no restriction on the lower limit, when the straight-run gas oil (LGO) fraction and the catalytic cracking gas oil (LCO) fraction used in the present invention are used, the total aromatic content is usually 19% by mass or more, and the polycyclic aromatic content is 1.6% by mass or more is contained. When the total aromatic amount and the polycyclic aromatic amount are less than or equal to these values, the particulate matter and NOx emission discharged from the diesel engine can be reduced. In addition, in this application document, the amount of aromatics means the value measured based on the rule of ASTM D5186.

  In the light oil composition of the present invention, HFRR is 420 μm or less. When the wear scar diameter of HFRR is 420 μm or less, it is possible to reduce the risk of abnormal wear occurring in the fuel injection pump of the diesel engine. In addition, in this application document, HFRR means the value measured based on the rule of ASTM D-6079.

  Moreover, various additives can be suitably mix | blended with the light oil composition of this invention as needed. Examples of such additives include cetane number improvers, surfactants, fluidity improvers, antiseptics, rust inhibitors, defoamers, detergents, antioxidants, hue improvers, and lubricity improvers. These fuel additives are mentioned. These can be added singly or in combination.

  The content of the present invention will be described in more detail with reference to Examples and Comparative Examples below, but the present invention is not limited thereto.

  In addition, about each light oil composition of an Example and a comparative example, the engine bench test was done using the engine shown in Table 1, and JE05 mode fuel consumption and exhaust gas discharge | emission amount (NOx, CO, THC) were measured. Regarding the fuel consumption, the fuel consumption of the light oil composition of Comparative Example 1 was set to 100%, and the light oil compositions of other Examples and Comparative Examples were relatively compared. In addition, the increase in the differential pressure before and after the DPF due to PM (particulate matter) discharged when the engine was operated for 2 hours under the constant operating condition of 1800 rpm and 100 Nm was measured.

[Examples 1-4, Comparative Examples 1-2]
First, the raw material base material which has a property as shown in Table 2 was mixed by the mixing | blending shown in Table 3. Thereafter, ULGO-1 to 6 were desulfurized using a CoMoP-supported desulfurization catalyst under the conditions shown in Table 3. On the other hand, a kerosene base (UKERO) is prepared by hydrodesulfurizing a straight-run kerosene (KERO) obtained by fractionating crude oil with an atmospheric distillation apparatus under the desulfurization conditions-7 shown in Table 3. did.
Table 4 shows the properties of the desulfurized light oil base material obtained by the desulfurization treatment.

  The obtained desulfurized gas oil base material was blended according to the fuel formulation shown in Table 5, and 150 mass ppm of a lubricity improver was further added to produce a light oil composition. Table 5 shows the properties of the obtained light oil composition and the performance obtained as a result of an engine bench test using the engine shown in Table 1.

  As a result, the light oil compositions of Examples 1 to 4 were obtained by desulfurizing straight-run kerosene and a desulfurized light oil base material obtained by desulfurizing only a straight-run light oil fraction having a 90% distillation temperature higher than 345 ° C. Compared to the light oil composition of Comparative Example 1 blended with the desulfurized kerosene base material obtained by the treatment, the fuel efficiency is low, and the increase in the differential pressure of the DPF due to PM deposition is suppressed. It turned out that there was little discharge. On the other hand, in the light oil composition of Comparative Example 2 in which the amount of LCO fraction mixed is large, the fuel efficiency improvement effect was confirmed as compared with the light oil composition of Comparative Example 1, but the DPF differential pressure increase was significant. In addition, deterioration of NOx, CO, and THC was confirmed. From these results, a raw material mixed oil obtained by mixing an LGO fraction having a 90% distillation temperature within a specific range and an LCO fraction having a 90% distillation temperature within a specific range at a specific mixing ratio is obtained. By using the light oil composition of the present invention including the desulfurized light oil base material obtained by the desulfurization treatment, it is apparent that both improvement in fuel efficiency and excellent exhaust gas performance can be achieved.

Claims (1)

A straight-run gas oil fraction having a 90% distillation temperature of 330 to 345 ° C. distilled from an atmospheric distillation apparatus, and a catalytic cracking gas oil fraction having a 90% distillation temperature of 320 to 350 ° C. obtained from a fluid catalytic cracker Is a gas oil composition comprising a desulfurized light oil base material obtained by desulfurizing a mixture of 95: 5 to 80:20 by volume ratio,
(A) a cetane number of 50-60,
(B) 90% distillation temperature is 282 to 336 ° C,
(C) 15 degreeC density is 0.832-0.848g / cm < ³ >,
(D) Flash point is 61 ° C or higher,
(E) Kinematic viscosity at 40 ° C. of 1.9 to 4.1 mm ² / s,
(F) Sulfur content is 50 mass ppm or less,
(G) The total aromatic content is 30% by mass or less,
(H) A light oil composition, wherein the polycyclic aromatic is 4.5% by mass or less, and (i) HFRR is 420 μm or less.