JP5955676B2 - Method of feeding oil to storage tank - Google Patents

Description

  The present invention relates to a method of feeding raw material oil to a storage tank, and more particularly to a method of sequentially feeding a plurality of raw material oils to a storage tank corresponding to the raw material oil using the same receiving pipe. is there.

  In the refinery, when the raw material oil is received in the refinery, the oil is sent to a storage tank corresponding to the raw material oil through a receiving pipe for receiving the raw material oil and stored. For example, crude oil transported by a tanker is sucked up by a pump, sent through a raw material oil receiving pipe, and stored in a crude oil storage tank.

  There are a plurality of types of raw material oil, and a plurality of storage tanks for the raw material oil are provided according to the type of the raw material oil. Therefore, depending on the type of raw material oil and the type of storage tank for raw material oil, it may be possible to provide multiple raw material oil receiving pipes, but considering the cost and installation space, the raw material oil receiving pipes are shared. By providing a tank switching valve on the outlet side (tank side) of the pipe, it is common to operate the valve and switch the flow path from the valve to a tank pipe connected to a plurality of raw oil storage tanks. is there.

  For example, Patent Document 1 discloses that a process for obtaining a base fraction by distilling crude oil, a process for obtaining various bases by refining the base fraction, and using a switching valve or the like. A method for producing a petroleum product, comprising: a step of storing in a material tank; a step of blending the base materials to obtain a petroleum product; and a step of storing the obtained product in a product tank using a valve or the like. The method for producing a petroleum product is characterized in that each step is individually controlled, and each step is optimized and controlled based on the properties of the base material or the blended petroleum product.

  However, by operating the tank switching valve and switching the flow path, when each raw material oil is sent to the corresponding storage tank, the raw material oil receiving pipe is shared. After that, when the flow path of the raw material oil is switched to the storage tank for the next raw material oil, the raw material oil that has been input first remains in the receiving pipe and is mixed in the storage tank for the raw material oil to be input later. There was a problem to do.

  If different types of raw material oils are mixed in the raw material oil storage tank as described above, if the compatibility of the respective raw material oils is poor, insoluble components such as sludge are generated in the storage tanks, There is a problem that storage stability deteriorates due to mixing of raw material oil. In order to satisfy the sulfur content standard in the product oil, the reaction temperature for hydrorefining raw material oil (raw oil introduced later) mixed with different raw oil (raw oil introduced earlier) is increased. There is a problem that the necessity arises and the cost increases.

JP-A-8-225788

  Therefore, the present invention is able to suppress mixing of different types of raw material oil into the raw material oil storage tank by performing appropriate control on the raw material oil remaining in the receiving pipe, and is excellent in storage stability and economy. An object of the present invention is to provide a method for feeding oil to a storage tank for raw material oil.

  The inventors of the present invention have intensively studied to solve the above-described problems with respect to a method of sequentially feeding two or more different raw oils to each raw oil storage tank using the same receiving pipe. As a result, after the physical properties of the mixed oil of the raw material oil previously introduced remaining in the receiving pipe and the raw material oil introduced later into the receiving pipe become below the reference value, By switching the tank, it is possible to suppress the mixing of different types of raw material oils (the raw material oils that have been input earlier) into the storage tanks for the raw material oils that have been input later, and excellent storage stability and economic efficiency. It was found that can be realized.

The present invention has been made based on such findings, and the gist thereof is as follows.
(1) A method of sequentially feeding two or more different raw oils to each raw oil storage tank using the same receiving pipe,
For storing each of the raw oils after the sulfur content or nitrogen content of the mixed oil of the raw material oil previously charged remaining in the receiving pipe and the raw material oil charged later into the receiving pipe falls below a reference value There line switching of the tank, the oil feeding method of sulfur or nitrogen of the reference value of the mixed oil (D mass ppm) is, to the storage tank of the feedstock, characterized in that it is obtained by the following equation.
D = A × (0.001 × C) + B × {1− (0.001 × C)}
In the formula, A: sulfur content or nitrogen content (mass ppm) in the feed oil introduced earlier, B: sulfur content or nitrogen content (mass ppm) in the feed stock introduced later, A> B, C = 4 is there.

( 2 ) The measurement of the sulfur content of the mixed oil is performed by measuring each raw material storage tank side outlet of the receiving pipe, an inlet of a valve for switching the flow path of the raw oil, or the storage tank of the raw oil previously introduced. The method for feeding the raw material oil to the storage tank according to the above (1) , characterized in that the method is carried out at the inlet of the tank.

( 3 ) The feedstock to be introduced later has a distillation property of 10 vol% distillation temperature of 35 to 80 ° C, 95 vol% distillation temperature of 230 to 400 ° C, and 97 vol% distillation temperature of 250 to 450 ° C. Have
The hydrocarbon oil having a value obtained by dividing the sulfur content of the naphtha fraction in the feed oil introduced later by the sulfur content of the feed oil introduced later is 0.1 or more and less than 1.5. (1) The oil feeding method to the storage tank of the raw material oil as described in (2) .

( 4 ) Distillation of the raw material oil to be introduced first is 10% by volume distillation temperature of 75-100 ° C, 95% by volume distillation temperature of 620-800 ° C, 97% by volume distillation temperature of 650-820 ° C. Has properties,
A value obtained by dividing the sulfur content of the naphtha fraction in the feed oil introduced first by the sulfur content of the feed oil introduced earlier is 0.001 or more and less than 0.1 hydrocarbon oil. The method for feeding oil to the storage tank of the raw material oil according to (1) or (2) .

  According to the present invention, it is possible to suppress the mixing of different types of raw material oils in the raw material oil storage tank, and it is possible to provide a method for feeding the raw material oil to the storage tank that is excellent in storage stability and economy. Become.

It is a figure for demonstrating the oil feeding method to the storage tank of the raw material oil by this invention, Comprising: The structure about one Embodiment of raw material oil, a receiving piping, and a storage tank is shown. It is a figure for demonstrating the oil feeding method to the storage tank of the raw material oil by this invention, Comprising: The storage tank for raw material oil which introduce | transduces the raw material oil previously injected | thrown-in through the raw material oil receiving piping previously Shows the state of oil transfer. It is a figure for demonstrating the oil feeding method to the storage tank of the raw material oil by this invention, Comprising: The raw material oil thrown into later starts to feed into a raw material oil receiving piping, and the raw material oil thrown in earlier is thrown in later The state which is sending the mixed oil with raw material oil to the storage tank of the raw material oil input previously is shown. It is a figure for demonstrating the oil feeding method to the storage tank of the raw material oil by this invention, Comprising: When the physical property of the said mixed oil becomes below a reference value, The state of oil transfer to the storage tank is shown. It is a figure for demonstrating the oil feeding method to the storage tank of the raw material oil by this invention, Comprising: The state which feeds the raw material oil thrown into later to the storage tank different from FIG. 3 is shown.

The present invention will be described below with reference to the drawings.
As shown in FIG. 1, the method for feeding raw material oil to the storage tank according to the present invention uses two or more different raw material oils to each of the raw oil storage tanks 10, 11, using the same receiving pipe 1. This is a method of sending oil to 12 sequentially.

  In the present invention, after the physical properties of the mixed oil of the raw material oil that has been previously introduced into the receiving pipe and the raw material oil that has been introduced into the receiving pipe are equal to or less than a reference value, The tank is switched.

  By having the above-described configuration, the mixed oil is supplied to the raw material oil storage tank having a property, sulfur content, and nitrogen content closer between the raw material oil introduced earlier and the raw material oil introduced later. Therefore, it is possible to effectively suppress mixing of different types of raw material oils in the raw material oil storage tank. As a result, it is possible to improve the stability and economy of raw material storage.

  In the conventional oil feeding method, when a new raw material oil (raw material oil introduced later) starts to be introduced into the receiving pipe, the valve is switched to a storage tank for the raw material oil introduced later. The raw material oil introduced earlier that remains in the pipe is mixed into the storage tank for the raw oil introduced later. As a result, the properties of the feedstock oil may fluctuate greatly, and the storage stability of the feedstock oil and the severeness of the equipment operating conditions during the hydrorefining treatment of the feedstock input after the above will be worsened. Will have an impact.

(Plumbing)
In the oil feeding method of the present invention, as shown in FIG. 1, the feed oil is sent to the feed oil storage tanks 10, 11, 12 using the receiving pipe 1. The configuration of the receiving pipe 1 is not particularly limited, and a receiving pipe normally used in a refinery may be used.

In the oil feeding method of the present invention, with regard to the switching of the storage tank for the raw material oil that is input from the receiving pipe, the raw material oil that has been input earlier that remains in the receiving pipe and the raw material oil that has been input later to the receiving pipe Is determined based on whether or not the physical properties of the mixed oil are below the reference value. Switching is performed depending on whether or not the value falls below the reference value, thereby enabling stable oil feeding and automatic control of oil feeding.
For example, first, as shown in FIG. 2, the raw material oil introduced first is sent to the storage tank for the raw material oil introduced first. Next, as shown in FIG. 3, when the feed of the feed oil to be introduced later is started after the feed of the feed oil introduced earlier, the physical properties (for example, sulfur content) of the mixed oil in the feed oil receiving pipe Until the oil becomes below the reference value, the mixed oil is continuously fed to the storage tanks 10a, 10b,. Then, as shown in FIG. 4, after the sulfur content of the mixed oil becomes below the reference value, the raw material oil storage tank 10a (or 10b, 10c,. Then, it switches to the storage tank 11 for the raw material oil introduced later and continues to feed the raw material oil introduced later.
In addition, as shown in FIG. 5, when oil is fed using a pipe in which the oil in the pipe such as the feedstock receiving pipe is appropriately replaced with the feedstock input later, another feed is performed later. The oil supply can be continued by switching to the storage tank 12 for the raw material oil.
Note that tank piping that is directly connected to the storage tank for the target raw material oil, such as piping other than the raw material oil receiving pipe, which is a common pipe regardless of the type of raw material oil, is usually used for the target raw material oil. Only passed.

  Here, the physical properties of the mixed oil are not particularly limited as long as it is a value capable of distinguishing between the feed oil introduced first and the feed oil introduced later, for example, sulfur content, nitrogen content, density, distillation properties The ratio of heavy components calculated from

About the said physical property, the said physical property requires that it is a sulfur content or a nitrogen content, and it can also use a sulfur content and a nitrogen content together. Since the sulfur content and the nitrogen content differ depending on the raw material oil, it is easy to grasp the timing at which the raw material oil is replaced. In addition, for example, when raw material oil with a high sulfur content or nitrogen content is mixed into the raw material storage tank, hydrorefining treatment is required to meet the standards, which causes economic deterioration. This is because excellent economic efficiency can be secured.

Moreover, the reference value of sulfur content of the mixed oil is obtained by the following formula as the reference value (D mass ppm) of the sulfur content of the mixed oil .
D = A × (0.001 × C) + B × {1− (0.001 × C)}
Here, A is the sulfur content (mass ppm) in the raw material oil introduced earlier, B is the sulfur content (mass ppm) in the raw material oil introduced later, and A> B, C = 4 is there.
The value of C was set to 4. When C exceeds 4, the physical properties and properties of the feed oil introduced earlier and the feed oil introduced later are greatly different, so the storage stability when each feedstock is mixed When the mixed oil and the mixed oil are supplied to a batch hydrorefining treatment (desulfurization) device, for example, it is necessary to increase the reaction temperature in order to keep the physical properties (sulfur content, etc.) in the hydrorefining treatment oil constant. This is because there is a possibility that deterioration of the catalyst is promoted due to an increase in the reaction temperature and the life of the catalyst is shortened, and there is a possibility that economic efficiency is deteriorated in terms of operating cost by increasing the reaction temperature. .

As one index of storage stability, there is a numerical value of asphaltenes, which is an index of the compatibility between the raw material oil introduced earlier and the raw material oil introduced later. An increase in this value means that by mixing two raw oils, a large amount of precipitates are generated from the oil, causing the equipment to become dirty and clogged during processing of the raw oil. . When the raw material oil introduced earlier is mixed in a certain amount or more later, the numerical value of the asphaltenes increases.
On the other hand, after the physical properties of the mixed oil of the feed oil introduced later and the feed oil introduced earlier become below the reference value, the tank piping and the storage tank are switched, and the feed oil introduced later When the oil is sent to the storage tank for oil, the raw material oil and its components that are still left in the common receiving pipe continue to be mixed into the raw material oil that was introduced later over a long period of time. Then, it is mixed in the storage tank for raw material oil introduced later. Considering the capacity of the storage tank for raw material oil used in ordinary refineries, the amount of raw material oil stored in the storage tank that has been refueled after the tank changeover is first in the common receiving pipe. The ratio of the amount of raw material oil and the amount of its components mixed is below the extent that the storage stability is not significantly deteriorated, and when the raw material oil is supplied to the hydrorefining (desulfurization) processing device, the processing conditions (reactions) The reference value is determined so that it does not affect the temperature or the like.
Here, since the mixed oil in the common receiving pipe immediately before switching between the pipe and the tank is not the raw material oil in the storage tank during oil feeding, the mixing ratio at this time is the highest. By determining the reference values for the physical properties of the oil, it is possible to prevent the storage stability and processing conditions from being greatly affected. In order to prevent this, it is preferable that when calculating the reference value D, the value of C satisfies A> B and C = 4. For example, a raw material oil having physical properties of the reference value D when C = 4 (for example, sulfur content) is supplied to a hydrorefining apparatus that is processing raw material oil of the same oil type as the raw material oil, and a raw material oil storage tank is provided. If the reaction temperature rises to 10 ° C or less to maintain the physical properties (for example, sulfur content) of the treated oil at a constant level and continue processing, the processing conditions will not be greatly affected. . When the degree of increase in the reaction temperature exceeds 10 ° C., the deterioration of the catalyst is promoted and the life of the catalyst may be shortened, the frequency of catalyst replacement is increased, and the operating cost associated with increasing the reaction temperature is increased. This is because the economic efficiency of the refining treatment may be deteriorated.
Further, even when the physical property of the mixed oil is changed from the sulfur content to the nitrogen content, it is possible to determine the reference value in the same formula as described above.

  Further, for the measurement of the sulfur content of the mixed oil, the raw material storage tank side outlet of the receiving pipe, the inlet of a valve for switching the flow path of the raw oil, or the raw oil previously introduced is described later. Preferably, it is carried out at the inlet of the storage tank. It is because it can suppress in advance that a different kind of raw material oil mixes by performing in front of the said storage tank.

  As shown in FIG. 1, a tank pipe 2 is provided as a pipe connecting the receiving pipe 1 and the raw material oil storage tanks 10, 11, 12. By providing the tank pipe 2, it is possible to feed a plurality of raw material oils using one receiving pipe.

  Furthermore, as shown in FIG. 1, a tank switching valve 3 can be provided between the receiving pipe 1 and each tank pipe 2. By operating the tank switching valve, the raw material oil in the receiving pipe 1 can be passed through the target tank pipe 2 and sent to the storage tanks 10, 11, 12. However, in the present invention, similarly to the tank switching valve, any means having a function of switching the flow path so that the raw material oil in the receiving pipe 1 is directed to each of the storage tanks 10, 11, 12 can be used. The tank switching valve 3 may not be used.

(Raw oil storage tank)
The raw oil storage tank is not particularly limited as long as it can store the raw oil, but the floating roof tank reduces the evaporation loss of the stored oil and eliminates the vapor phase to maintain safety. It is often used for oil storage.

  In addition, the raw material oil storage tank can include one storage tank for each raw material oil, or the storage tank can be divided into several parts to store a plurality of raw material oils. .

(Raw oil)
In the present invention, two or more kinds of raw material oils are sent to a storage tank. The type of the raw material oil is not particularly limited, and various raw material oils can be used.
In the present invention, when two or more kinds of raw material oils are sent to the storage tank, the raw material oil that has been input first into the receiving pipe is referred to as “first input raw material oil”, the previous raw material When the next raw material oil is introduced into the receiving pipe after the oil has been introduced into the receiving pipe, the raw material oil is referred to as “raw oil that was introduced later”.

Further, when the mixed oil of the feed oil introduced later and the feed oil introduced earlier is mixed into the feed oil storage tank for batch hydrorefining of the feed oil introduced later, The impact on the storage stability of the raw material oil in the tank and the operation of the batch hydrorefining (desulfurization) equipment is great.
For example, when operation is performed with the sulfur content of the product after the batch hydrorefining treatment made constant, the reaction temperature rises rapidly, or in the storage tank or pipe, in the batch hydrotreating device, etc. There is a risk that precipitates may be generated and cause troubles such as clogging. Therefore, because the above-mentioned storage stability and the influence on the operation are likely to be large, and the effect of the present invention is remarkably exhibited, the feedstock to be introduced after the subject of the present invention is 10% by volume distillation temperature. Is preferably 35 to 80 ° C, more preferably 36 to 72 ° C, and a 95% by volume distillation temperature is preferably 230 to 400 ° C, more preferably 250 to 350 ° C, and 97 volumes. % Distillation temperature is preferably 250 to 450 ° C., more preferably 250 to 400 ° C. Furthermore, it is preferable to use a hydrocarbon oil in which the value obtained by dividing the sulfur content of the naphtha fraction obtained by atmospheric distillation by the sulfur content of the raw material oil is 0.1 or more and less than 1.5. However, it can be appropriately adjusted within the range not departing from the above numerical range depending on the usage of each fraction.

  In the present invention, the value obtained by dividing the sulfur content of the naphtha fraction by the sulfur content of the feedstock oil is a distillation apparatus (an apparatus for separating a liquid mixture using a difference in boiling points as a naphtha fraction,・ Fractionation at a boiling point of 150 ℃ from liquid hydrocarbons at room temperature and normal pressure with 5 carbon atoms using a device that can separate a liquid or solid mixture at normal pressure by distillation as a liquid mixture by adjusting the temperature and pressure Means the ratio of the sulfur content of the naphtha fraction and the sulfur content of the feedstock. In general, the naphtha fraction has a boiling range of about 30 to 200 ° C.

In the present invention, the value obtained by dividing the sulfur content of the naphtha fraction in the feed oil introduced later by the sulfur content of the feed oil introduced later is preferably 0.1 or more and less than 1.5, more preferably 0.5 or more and less than 1.2. It is. In addition, the sulfur content of the naphtha fraction in the feed oil introduced later is preferably in the range of 200 to 8000 wtppm, and the sulfur content of the feed oil introduced later is preferably in the range of 10 to 3000 wtppm. The batch hydrorefining process (desulfurization) in the present invention is a process of hydrotreating a fraction obtained by removing at least light gas and LP gas from a hydrocarbon oil as a raw material, so sulfur contained in each fraction. Due to the difference in the desulfurization reactivity of the minute, the desulfurization reactivity of the lighter fraction becomes higher. Therefore, by using a feedstock that has a high sulfur content in the naphtha fraction (or a sulfur content in the naphtha fraction that is higher than the sulfur content of other fractions such as kerosene fraction and diesel oil fraction) The reaction temperature can be set by paying attention to the desulfurization rate of the kerosene fraction and the light oil fraction.
For example, when the reaction conditions are set for refining sulfur-free light oil (sulfur content of 10 mass ppm or less), the lighter fractions will have less sulfur content than light oil fractions, such as light naphtha and heavy naphtha. In addition, a product having a desired quality can be obtained even for those having a sulfur content lower than that of light oil.

  Specific examples of the raw material hydrocarbon oil include natural gas condensate. Natural gas condensate is a liquid hydrocarbon at normal temperature and pressure obtained during the process of collecting and refining natural gas from a natural gas field, and is extremely light and naphtha compared to general crude oil obtained from oil fields. It is close to the property. The natural gas condensate is a light oil with an API specific gravity of 50 or more, which is widely used in Western countries as a specific gravity of petroleum, and has a low sulfur content, so an API specific gravity of 20-50 has a sulfur content of about 0-3%. It is a feedstock that can refine more light petroleum products such as gasoline than crude oil. Examples of natural gas condensate include, but are not limited to, South Perth condensate and Northfield condensate produced in the Middle East. Moreover, as said raw material hydrocarbon oil, it is also possible to use what was made into the hydrocarbon oil which has the said distillation property and sulfur content by mixing the some hydrocarbon oil which has a different property.

  On the other hand, as for the raw material oil to be input first, for example, a mixed oil of the raw material oil that has been input first and the raw material oil that has been input later is a raw oil storage for hydrorefining the raw material oil that is input first. Even if it is mixed in the tank for use, the storage stability of the feedstock in the feedstock storage tank and the influence of the feedstock in the feedstock storage tank on operation tend to be small. However, even in that case, the influence on the storage stability and operation caused by the mixed oil of the feed oil to be fed later and the feed oil to be fed earlier tends to be large, and the effect of the present invention is remarkably exhibited. It is preferable that the feedstock oil to be charged at the beginning of the invention has a 10% by volume distillation temperature of 75 to 100 ° C, more preferably 75 to 90 ° C, and a 95% by volume distillation temperature of 620 to 800 ° C. Preferably, the distillation property is such that the temperature is preferably 620 to 750 ° C, and the 97 vol% distillation temperature is preferably 650 to 820 ° C, more preferably 650 to 800 ° C. Furthermore, it is preferable to use a hydrocarbon oil having a value obtained by dividing the sulfur content of the naphtha fraction obtained by atmospheric distillation by the sulfur content in the raw material oil of 0.001 or more and less than 0.1. However, it can be appropriately adjusted within the range not departing from the above numerical range depending on the usage of each fraction.

  In addition, the place mentioned above only showed an example of embodiment of this invention, A various change can be added according to the description content of a claim.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

In Examples and Comparative Examples, distillation properties, density, and sulfur content were performed according to the following methods.
・ Distillation properties: “Petroleum products-Distillation test method” specified in JIS K 2254
-Density: The density at 15 ° C is measured in accordance with "Oscillation type density test method" in "Crude oil and petroleum products-Density test method and density / mass / capacity conversion table (excerpt)" specified in JIS K 2249. Is.
・ Sulfur content: Measured according to “Radiation Excitation Method” of “Crude Oil and Petroleum Products—Sulfur Content Test Method” defined in JIS K2541-1992.
Nitrogen content: Measured in accordance with “chemiluminescence method” or “microcoulometric titration method” of “crude oil and petroleum products—nitrogen content test method” defined in JIS K 2609-1998.

Example 1
As shown in FIG. 1, two different types of raw material oils were sequentially sent to each raw material oil storage tank using the same receiving pipe. The raw material oil previously introduced into the receiving pipe is an Arabian heavy crude oil produced in Saudi Arabia. The properties are shown in Table 1, and the yield and properties of each fraction are shown in Table 2. The feedstock later introduced into the receiving pipe is a condensate (lasgas condensate) obtained from the Northfield gas field in Qatar. Table 3 shows the properties and Table 4 shows the yield and properties of each fraction.
In addition, the switching of each raw material oil storage tank, the sulfur content (mass ppm) of the mixed oil of the raw material oil previously introduced into the receiving pipe and the raw material oil introduced later into the receiving pipe, Assuming that the sulfur content of the feed oil introduced earlier is A (mass ppm) and the sulfur content of the feed oil introduced later is B (mass ppm), D = A × (0.001 × C) + B × { 1− (0.001 × C)} was calculated when the value was equal to or less than the reference value D when C = 4. For the sulfur content and nitrogen content of the mixed oil, a sample obtained from a nozzle (not shown) provided at the outlet on the storage tank side of the raw material oil (lass gas condensate) introduced later in the receiving pipe is used. It was measured.
In other words, the sulfur content of the feed oil (Arabyan heavy crude oil) introduced earlier was 28100 mass ppm, and the sulfur content of the feed oil (rasgas condensate) introduced later was 2280 ppm by mass. Confirm that sulfur content D (mass ppm) of the mixed oil calculated with these values and C = 4 is 2383 mass ppm or less, and operate the tank switching valve to store the raw oil. The tank was switched.
At this time, the nitrogen content of the feed oil (Arabyan heavy crude oil) introduced earlier was 1270 mass ppm, and the nitrogen content of the feed oil (rasgas condensate) introduced later was 9.6 ppm by mass. These values and C = 4 The reference value D ′ (mass ppm) of the nitrogen content of the mixed oil calculated in step 1 is 14.6 mass ppm, but the nitrogen content of the mixed oil when the tank switching valve is operated is 14.6 mass ppm. It was below.
As a result, the fluctuation of the reaction temperature of the batch hydrorefining (desulfurization) apparatus when the tank switching valve was operated was 10 ° C. or less. Further, the value of the asphaltene content of the mixed oil was also inferior to that of the raw material oil introduced later, and there was no trouble such as storage stability in the tank or clogging due to generation of precipitates.

(Example 2)
When the above-mentioned Lasgas condensate and Arabian heavy crude oil are A (mass ppm) and the sulfur content of the Lasgas condensate is B (mass ppm), the sulfur content D in the raw oil mixed with both Is light by atmospheric distillation from a raw material mixed so as to satisfy the relational expression of D = A × (0.001 × C) + B × {1- (0.001 × C)} in a numerical range of C = 0 to 4 A continuous fraction from light naphtha excluding gas and LP gas (all fractions of liquid hydrocarbons at room temperature and normal pressure having 5 or more carbon atoms) was used as a feedstock.
Thereafter, the raw material oil was put into a reactor having an inner diameter of 10 mm and a length of 500 mm, and a downward co-current reactor to which 15 cc of a commercially available Co-Mo catalyst was added, hydrogen purity: 100%, pressure: 5 MPa, H ₂ / Oil ratio: 160 Nm ³ / kL, LHSV: 2.0 h ⁻¹ The continuous fractions from light naphtha to light oil were collectively hydrorefined.
Regarding the reaction temperature, the hydrotreated refined oil was transferred to a fractionator and distilled at atmospheric pressure to separate a light oil fraction (250 ° C to 350 ° C fraction). The residual sulfur concentration in this fraction was 10%. Adjustments were made to achieve ppm by mass.
As a result, when the value of the constant C was 0, the reaction temperature when the residual sulfur in the light oil was 10 ppm by mass was 300 ° C. The reaction temperature when the value of the constant C was 4 was 310 ° C. As a result, it was found that when the constant C is in the range of 0 to 4, the increase in the reaction temperature can be suppressed to 10 ° C. or less, the influence on the apparatus is small, and an economical result is obtained.

(Comparative Example 1)
In Example 2, when the sulfur content of Arabian heavy crude oil is A (mass ppm) and the sulfur content of Lasgas condensate is B (mass ppm), the value of C exceeds 4 and satisfies the relational expression. Continuous fraction from light naphtha from which light gas and LP gas are removed by atmospheric distillation from raw material oil mixed in the range of (ppm by mass) (all hydrocarbons at room temperature and normal pressure with 5 or more carbon atoms) Distillate) was used as the feedstock.
Thereafter, the raw material oil was put into a reactor having an inner diameter of 10 mm and a length of 500 mm, and a downward co-current reactor to which 15 cc of a commercially available Co-Mo catalyst was added, hydrogen purity: 100%, pressure: 5 MPa, H ₂ / Oil ratio: 160 Nm ³ / kL, LHSV: 2.0 h ⁻¹ The continuous fractions from light naphtha to light oil were collectively hydrorefined.
Regarding the reaction temperature, the hydrotreated refined oil was transferred to a fractionator and distilled at atmospheric pressure to separate a light oil fraction (250 ° C to 350 ° C fraction). The residual sulfur concentration in this fraction was 10%. Adjustments were made to achieve ppm by mass.
As a result, when the value of the constant C was 7, the reaction temperature when the residual sulfur in the light oil was 10 ppm by mass was 320 ° C. The reaction temperature when the value of the constant C was 15 was 370 ° C. As a result, it was found that when the value of C exceeds 4, the reaction temperature exceeds 10 ° C. and the influence on the apparatus is large.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that a different kind of raw material oil mixes in a raw material oil storage tank, and the oil supply to the storage tank of the raw material oil excellent in storage stability and economical efficiency is attained. As a result, it is industrially useful in that high purity raw material oil can be stably recovered.

DESCRIPTION OF SYMBOLS 1 Receiving pipe 10 Raw material oil storage tank 11 for raw material oil introduced earlier Raw material oil storage tank 12 for raw material oil introduced later 12 Raw material oil storage tank for raw material oil introduced later

Claims (4)

A method of sequentially feeding two or more different feedstocks to each feedstock storage tank using the same receiving pipe,
For storing each of the raw oils after the sulfur content or nitrogen content of the mixed oil of the raw material oil previously charged remaining in the receiving pipe and the raw material oil charged later into the receiving pipe falls below a reference value There line switching of the tank, the oil feeding method of sulfur or nitrogen of the reference value of the mixed oil (D mass ppm) is, to the storage tank of the feedstock, characterized in that it is obtained by the following equation.
D = A × (0.001 × C) + B × {1− (0.001 × C)}
In the formula, A: sulfur content or nitrogen content (mass ppm) in the feed oil introduced earlier, B: sulfur content or nitrogen content (mass ppm) in the feed stock introduced later, A> B, C = 4 is there. The sulfur or nitrogen content of the mixed oil is measured at the outlet side of each raw material storage tank of the receiving pipe, the inlet of a valve for switching the flow path of the raw material oil, or the storage tank of the raw material oil previously introduced. The method for feeding oil to a storage tank for raw material oil according to claim 1 , wherein the method is carried out at the inlet of the oil. The feedstock to be introduced later has a distillation property such that a 10% by volume distillation temperature is 35 to 80 ° C, a 95% by volume distillation temperature is 230 to 400 ° C, and a 97% by volume distillation temperature is 250 to 450 ° C. ,
The hydrocarbon oil having a value obtained by dividing the sulfur content of the naphtha fraction in the feed oil introduced later by the sulfur content of the feed oil introduced later is 0.1 or more and less than 1.5. A method for feeding the raw material oil according to 1 or 2 to a storage tank. The above-mentioned raw material oil has a distillation property with a 10% by volume distillation temperature of 75 to 100 ° C, a 95% by volume distillation temperature of 620 to 800 ° C, and a 97% by volume distillation temperature of 650 to 820 ° C. And
A value obtained by dividing the sulfur content of the naphtha fraction in the feed oil introduced first by the sulfur content of the feed oil introduced earlier is 0.001 or more and less than 0.1 hydrocarbon oil. A method for feeding the raw material oil according to claim 1 or 2 to a storage tank.