Gasoline production equipment

Abstract

To provide a gasoline production apparatus capable of efficiently producing gasoline as a renewable fuel.SOLUTION: A gasoline production apparatus 100 comprises a mixer 24 that blends FT naphtha containing olefin and FT naphtha not containing olefin to achieve a predetermined olefin content.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a gasoline production apparatus for producing gasoline as a renewable fuel. [Background technology]

[0002] Conventionally, there has been known an apparatus for producing hydrocarbons such as gasoline from carbon dioxide and hydrogen (see, for example, Patent Document 1). In the apparatus described in Patent Document 1, water is removed from a mixed gas containing carbon monoxide, carbon dioxide, hydrogen, and water obtained by reacting carbon dioxide with hydrogen, and hydrocarbons having a carbon number of 2 or more are produced through methanol. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-44926 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the device described in Patent Document 1, hydrocarbons are produced via methanol, but methanol is toxic, and when it is used as a fuel such as gasoline, the entire amount of methanol must be converted, which requires a lot of energy and makes it difficult to produce hydrocarbons efficiently. [Means for solving the problem]

[0005] A gasoline production apparatus according to one embodiment of the present invention includes a mixer that mixes an FT naphtha containing olefins and an FT naphtha not containing olefins so as to obtain a predetermined olefin content, a first supply unit that supplies a crude naphtha obtained by fractionating an FT crude oil obtained by FT synthesis to the mixer as an FT naphtha containing olefins without hydrogenating the crude naphtha, and a second supply unit that hydrogenates the crude naphtha and supplies it to the mixer as an FT naphtha not containing olefins. 。 Effect of the Invention

[0006] According to the present invention, gasoline as a renewable fuel can be efficiently produced. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram for explaining renewable fuel produced using renewable energy. [Diagram 2] FIG. 2 is a diagram for explaining an octane improver. [Figure 3A] FIG. 2 is a block diagram showing an example of the configuration of a fractionation section of a gasoline production apparatus according to an embodiment of the present invention. [Figure 3B] FIG. 2 is a block diagram showing another example of the configuration of the fractionation section of a gasoline production apparatus according to an embodiment of the present invention. [Figure 4] FIG. 4 is a diagram for explaining the octane number of crude naphtha fractionated in the first distillation column of FIGS. 3A and 3B. [Diagram 5] FIG. 2 is a block diagram showing an example of the configuration of a mixing unit of a gasoline production apparatus according to an embodiment of the present invention. [Figure 6] 1 is a flowchart showing an example of a gasoline production method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to Figures 1 to 6. A gasoline production device according to an embodiment of the present invention fractionates FT crude oil obtained by FT (Fischer-Tropsch) synthesis using renewable electricity into FT naphtha, FT kerosene, FT diesel, etc., and produces gasoline as a renewable fuel from the FT naphtha.

[0009] The average temperature of the Earth is kept warm enough for living things by greenhouse gases in the atmosphere. Specifically, greenhouse gases absorb some of the heat radiated from the Earth's surface, which is warmed by sunlight, into space, and then re-radiate it back to the Earth's surface, thereby keeping the atmosphere warm. If the concentration of greenhouse gases in the atmosphere increases, the average temperature of the Earth will rise (global warming).

[0010] Carbon dioxide, which is one of the greenhouse gases that contributes most to global warming, has a concentration in the atmosphere that is determined by the balance between carbon fixed on the ground or in the earth as plants and fossil fuels, and carbon present in the atmosphere as carbon dioxide. For example, when carbon dioxide in the atmosphere is absorbed by plants through photosynthesis during growth, the concentration of carbon dioxide in the atmosphere decreases, and when carbon dioxide is released into the atmosphere through the combustion of fossil fuels, the concentration of carbon dioxide in the atmosphere increases. To prevent global warming, it is necessary to replace fossil fuels with renewable energy sources such as solar, wind, hydroelectric, geothermal, or biomass, and reduce carbon emissions.

[0011] FIG. 1 is a diagram for explaining renewable fuels produced using such renewable energy. As shown in FIG. 1, renewable electricity is generated by solar power generation, wind power generation, hydroelectric power generation, geothermal power generation, etc., and renewable hydrogen is produced by electrolysis of water using the renewable electricity. Furthermore, renewable hydrogen and carbon dioxide captured from factory exhaust gases, etc. are used to produce renewable fuels by FT synthesis or methanol synthesis. Since methanol is toxic, when producing gasoline via methanol, the entire amount of methanol needs to be converted, which requires a lot of energy.

[0012] Due to the principle of the FT synthesis process, which is a polymerization reaction, FT crude oil obtained by FT synthesis contains a variety of components. Such FT crude oil is fractionated according to the boiling point range and separated into FT diesel, FT kerosene, FT naphtha, etc. Of these, FT diesel can be used as fuel for diesel engines, and FT kerosene can be used as fuel for jet engines.

[0013] FT naphtha contains normal paraffins with carbon numbers of about 5 to 9 as the main component. It also contains olefins as secondary components at a content rate according to the catalyst, reaction temperature, reaction time, etc. used in the FT synthesis process. Such FT naphtha is suitable as a gasoline base material because its vapor pressure characteristics (vaporization characteristics) comply with gasoline standards. On the other hand, FT naphtha has an octane number (research method octane number) of about 50 to 80, which is lower than the gasoline standard (about 90), and if it is used as fuel for gasoline engines as it is, knocking may occur and the combustion performance of the engine may be impaired.

[0014] Conventionally, naphtha obtained by fractional distillation of crude oil has been catalytically reformed into isoparaffins and aromatic hydrocarbons, and mixed with olefins obtained by catalytic cracking of heavy oil components obtained by fractional distillation of crude oil, or alkylates obtained by alkylation, to improve the octane number. However, since FT synthesis for producing renewable fuels is performed under conditions that increase the yield of FT kerosene, etc., FT crude oil contains almost no heavy oil components, and it is difficult to improve the octane number by mixing olefins obtained by catalytic cracking of heavy oil components with FT naphtha. In addition, when increasing the proportion of naphtha catalytically reformed into aromatic hydrocarbons, it is difficult to efficiently improve the octane number.

[0015] Fig. 2 is a diagram for explaining octane number improvers, and shows an example of the measurement results of the octane number of a mixed fuel obtained by mixing various octane number improvers with PRF (Primary Reference Fuel) 65, which is a mixture of isooctane and normal heptane in a volume ratio of 65:35 and has an octane number of 65. As shown in Fig. 2, when toluene (aromatic hydrocarbon) is mixed as an octane number improver, a larger amount is needed to improve the octane number to the gasoline standard (about 90) than when ethanol or diisobutylene (olefin) is mixed.

[0016] The combustion reaction of hydrocarbons is a chain reaction that progresses with the production and consumption of OH radicals, and when combusted alone, the initial combustion reaction is suppressed in hydrocarbons that are difficult to extract hydrogen atoms from and therefore difficult to produce OH radicals, resulting in a higher octane number. For example, isooctane, which has side chains, has a higher octane number than straight-chain normal heptane.

[0017] Olefins are unsaturated hydrocarbons with one double bond. Olefins with three or more carbon atoms contain an allyl group (-CH 2 CH=CH 2 ) The bond energy between the carbon atom adjacent to the double bond of the allyl group and the hydrogen atom is low, and the hydrogen atom is easily removed. When such an olefin is mixed with a hydrocarbon base material as an octane number improver, the OH radicals generated in the initial combustion reaction of the hydrocarbon base material react preferentially with the hydrogen atoms removed from the allyl group of the olefin, and are consumed, suppressing the combustion reaction (chain reaction). In addition, the olefin itself remains in a stable state even after the hydrogen atoms are removed due to allyl resonance stabilization, and is less likely to generate OH radicals. In other words, not only does the olefin have a high octane number by itself, but when mixed with a hydrocarbon base material, it has the effect of suppressing the combustion reaction by consuming the OH radicals generated in the initial combustion reaction of the hydrocarbon base material, thereby improving the octane number (synergistic effect).

[0018] Therefore, when an FT naphtha base material, which is mainly composed of normal paraffin, is mixed with an olefin, the octane number is increased to a value higher than that predicted according to the octane number and the mixing ratio of both components due to a synergistic effect. On the other hand, when toluene is mixed with an FT naphtha base material, the octane number is increased only to a value predicted according to the octane number and the mixing ratio of both components. Therefore, in this embodiment, a gasoline production device is configured as follows so that gasoline as a renewable fuel can be efficiently produced by utilizing the synergistic effect of improving the octane number by the olefin.

[0019] 3A and 3B are block diagrams showing an example of the configuration of fractionation units 10, 10A of a gasoline production apparatus (hereinafter, apparatus) 100 according to an embodiment of the present invention. As shown in FIG. 3A, fractionation unit 10 has a first distillation column 11, an oxidation prevention processing section 12, hydrogenation processing sections 13, 14, and a second distillation column 15. The first distillation column 11 contains CO 2 , which is a by-product when producing bioethanol from biomass such as corn. 2 FT crude oil will be supplied as a renewable fuel, synthesized by FT synthesis using crude oil and hydrogen obtained by electrolysis of water using renewable energy.

[0020] In the first distillation column 11, the FT crude oil is fractionated into a crude naphtha (carbon number 5 to 9) containing olefins and having a boiling point of 150° C. or less, a crude middle distillate (carbon number 10 to 21) having a boiling point of 150° C. to 360° C., and a crude wax fraction (carbon number 22 or more) having a boiling point of 360° C. or more. The crude naphtha is supplied to an oxidation prevention treatment section 12, the crude middle distillate is supplied to a hydrotreating treatment section 13, and the crude wax fraction is supplied to a hydrotreating treatment section 14.

[0021] The oxidation prevention treatment unit 12 is provided adjacent to the first distillation tower 11, and adds a very small amount (about several ppm) of an antioxidant such as BHT (dibutylhydroxytoluene) to the crude naphtha immediately after fractionation in the first distillation tower 11, and supplies the crude naphtha to the storage unit 21 (FIG. 5). The oxidation prevention treatment unit 12 can be provided, for example, in a condenser that condenses the vapor of the crude naphtha discharged from the first distillation tower 11.

[0022] Conventionally, naphtha fractions obtained by distillation of crude oil are first hydrotreated, then a portion of them is catalytically reformed into isoparaffins and aromatic hydrocarbons, and olefins obtained by catalytic cracking of heavy oil fractions are mixed in to improve the octane number. At this time, the olefins contained in the naphtha fraction immediately after distillation are converted to paraffins by hydrogenation (addition reaction), which reduces the octane number of the naphtha fraction. To make up for this, the octane number is improved by catalytic reforming or by mixing olefins from the heavy oil fraction.

[0023] By using the olefin-containing crude naphtha fraction without hydrogenation, the octane number can be efficiently improved. Also, by adding an antioxidant to the crude naphtha fraction immediately after fractionation, the oxidation of the olefins can be prevented, and the decrease in the octane number due to the reduction in the olefins can be prevented.

[0024] The hydrotreating sections 13 and 14 hydrogenate the crude middle fraction and the crude wax fraction fractionated in the first distillation column 11, respectively, and supply them to the second distillation column 15. The hydrotreating sections 13 and 14 use renewable hydrogen.

[0025] In the second distillation column 15, the hydrogenated crude middle fraction and crude wax fraction are fractionated into FT naphtha containing no olefins, FT kerosene, FT diesel, and a wax fraction. Of the fractions obtained from the second distillation column 15, the FT naphtha containing no olefins is supplied to the storage section 22 (FIG. 5), and the wax fraction is supplied to the hydrotreating section 14 and hydrogenated again.

[0026] As shown in FIG. 3B, in addition to the configuration of the fractionation section 10 in FIG. 3A, the fractionation section 10A has a hydrotreating section 16 that hydrogenates a portion of the crude naphtha fractionated in the first distillation column 11 and supplies it to the storage section 22 (FIG. 5). In this case, for example, two condensers are provided to condense the vapor of the crude naphtha discharged from the first distillation column 11, and an oxidation prevention processing section 12 is provided in one of the condensers, while liquid crude naphtha discharged from the other condenser is supplied to the hydrotreating section 16. Renewable hydrogen is also used in the hydrotreating section 16.

[0027] FIG. 4 is a diagram for explaining the octane number of the crude naphtha fractionated in the first distillation column 11, and shows the octane number of typical olefins having 5 to 9 carbon atoms. As shown in FIG. 4, the average octane number of typical olefins having 5 to 9 carbon atoms is about 93, which is higher than the octane number of the entire naphtha (about 50 to 80). Therefore, the octane number of low-boiling olefins (having 5 to 9 carbon atoms) contained in the crude naphtha fraction is higher than the octane number of the entire naphtha, and by increasing the mixing ratio of such olefins, the octane number can be improved regardless of the presence or absence of a synergistic effect.

[0028] Fig. 5 is a block diagram showing an example of the configuration of the mixing section 20 of the unit 100. As shown in Fig. 3A, Fig. 3B, and Fig. 5, the unit 100 includes fractionation sections 10 and 10A that fractionate FT crude oil and perform necessary processing, and a mixing section 20 that mixes the FT naphtha containing olefins and the FT naphtha not containing olefins that have been fractionated and processed in the fractionation sections 10 and 10A.

[0029] As shown in FIG. 5, the mixing section 20 has storage sections 21, 22, 23, mixers 24, 27, an olefin content / octane number measuring section 25, a catalytic reforming section 26, and an octane number measuring section 28. The storage section 21 is supplied with and stores FT naphtha containing olefins to which an antioxidant has been added in the oxidation prevention treatment section 12. The storage section 22 is supplied with and stores FT naphtha containing no olefins that has been fractionated in the second distillation column 15 and FT naphtha containing no olefins that has been hydrogenated in the hydrotreatment section 16. The storage section 23 stores bioethanol produced from biomass such as corn.

[0030] The storage sections 21, 22 and the mixer 24 are connected via piping R10, and FT naphtha containing olefins is supplied from the storage section 21 to the mixer 24 via piping R10, and FT naphtha containing no olefins is supplied from the storage section 22 to the mixer 24. The FT naphtha containing olefins from the storage section 21 and the FT naphtha containing no olefins from the storage section 22 are mixed in the piping R10 and in the mixer 24 to become a mixed fuel.

[0031] The pipe R11 connecting the storage section 21 and the mixer 24 is provided with an adjustment valve 21a for adjusting the supply amount of FT naphtha containing olefins, which is supplied from the storage section 21 to the mixer 24 and becomes part of the mixed fuel. The pipe R12 connecting the storage section 22 and the mixer 24 is provided with an adjustment valve 22a for adjusting the supply amount of FT naphtha not containing olefins, which is supplied from the storage section 22 to the mixer 24 and becomes part of the mixed fuel. The adjustment valves 21a, 22a may be operated manually or may be controlled by a computer 29. Hereinafter, the oxidation prevention treatment section 12 (FIGS. 3A and 3B), the storage section 21, and the adjustment valve 21a may be referred to as a first supply section that supplies the FT naphtha containing olefins to the mixer 24. In addition, the hydrotreating section 16 (FIG. 3B), the storage section 22, and the regulating valve 22a may be referred to as a second supply section that supplies FT naphtha that does not contain olefins to the mixer 24.

[0032] An olefin content / octane number measuring unit 25 for measuring the olefin content and octane number of the mixed fuel is provided in the pipe R10 connecting the storage units 21, 22 and the mixer 24. The olefin content / octane number measuring unit 25 has a measuring device such as a near-infrared spectrometer, measures the olefin content and octane number of the mixed fuel flowing through the pipe R10, and outputs the measurement results to a display or a computer for controlling the regulating valve. The olefin content / octane number measuring unit 25 may sample the mixed fuel flowing through the pipe R10 and measure the octane number by a combustion test.

[0033] As shown in FIG. 2, the larger the difference ΔRON between the octane number predicted according to the octane number and blending ratio of the base material and additives shown by the dashed line and the actual octane number of the blended fuel shown by the solid line, the greater the synergistic effect when olefin is blended with the FT naphtha base material. The synergistic effect when olefin is blended with the FT naphtha base material is maximized when the blending ratio of olefin is 50% by volume, so from the viewpoint of efficiently improving the octane number of the blended fuel, it is preferable to set the blending ratio of olefin to 50% by volume or less. In addition, if the blending ratio of olefin is excessive, non-volatile gums are generated, so it is preferable to set the blending ratio of olefin to about 10 to 25% by volume.

[0034] The adjusting valves 21a and 22a are operated to adjust the supply amount of FT naphtha containing olefins and FT naphtha not containing olefins so that the octane number corresponds to the gasoline standard (about 90) within the range of about 10 to 25% by volume of the olefin content measured by the olefin content / octane number measuring unit 25. This allows even FT naphtha with a wide range of properties such as octane number to be adjusted to an octane number corresponding to the gasoline standard. In addition, the synergistic effect of mixing naphtha and olefins allows the octane number to be efficiently improved.

[0035] The storage unit 23 and the mixer 24 are connected via a pipe R20, and bioethanol is supplied from the storage unit 23 to the mixer 24 via the pipe R20. The bioethanol from the storage unit 23 is added to and mixed in the mixer 24 with a mixed fuel of FT naphtha containing olefins and FT naphtha not containing olefins. The pipe R20 connecting the storage unit 23 and the mixer 24 is provided with an adjustment valve 23a that adjusts the amount of bioethanol supplied from the storage unit 23 to the mixer 24. The adjustment valve 23a may be operated manually or may be controlled by a computer 29.

[0036] The storage section 22 and the mixer 24 are further connected via a pipe R30. A catalytic reforming section 26 is provided in the pipe R30, and FT naphtha not containing olefins is supplied from the storage section 22 to the catalytic reforming section 26 via the pipe R30, and reformed gasoline after catalytic reforming is supplied from the catalytic reforming section 26 to the mixer 24 via the pipe R30. The catalytic reforming section 26 catalytically reforms (cyclization dehydrogenation reaction) the FT naphtha not containing olefins to generate reformed gasoline containing aromatic hydrocarbons such as toluene. Of the FT naphtha not containing olefins stored in the storage section 22, only heavy naphtha with a low octane number separated by, for example, distillation may be supplied to the catalytic reforming section 26 and reformed. A piping R30 between the storage section 22 and the catalytic reforming section 26 is provided with an adjustment valve 22b that adjusts the supply amount of FT naphtha not containing olefins supplied from the storage section 22 to the catalytic reforming section 26, i.e., the supply amount of reformed gasoline reformed in the catalytic reforming section 26 and supplied to the mixer 24. The adjustment valve 22b may be operated manually or may be controlled by a computer 29.

[0037] If the octane number of the mixed fuel measured by the olefin content / octane number measuring unit 25 does not reach the gasoline standard, the adjusting valves 23a, 22b are operated to adjust the supply amount of bioethanol and reformed gasoline so that the octane number of the mixed fuel reaches the gasoline standard. The amount of bioethanol and reformed gasoline added to the mixed fuel is calculated based on a characteristic map previously set by testing according to the octane number of the mixed fuel before addition. By calculating the appropriate amount to be added based on the characteristic map previously set by testing, excessive bioethanol or reformed gasoline is not added, and the olefins in the mixed fuel are not excessively diluted.

[0038] As shown in FIG. 2, the synergistic effect when ethanol is mixed with the FT naphtha base material is maximized when the mixing ratio is 50% by volume, similar to olefins. Therefore, from the viewpoint of efficiently improving the octane number, it is preferable to set the mixing ratio of bioethanol to 50% by volume or less. In addition, since the calorific value decreases when the mixing ratio of alcohols is excessive, the mixing ratio of bioethanol is set to 20% by volume or less, preferably 10% by volume or less. In this case, the content of FT naphtha in the mixed fuel is 50% or more. This makes it possible to more reliably adjust the octane number of the mixed fuel to the gasoline standard, and the synergistic effect of mixing naphtha and ethanol makes it possible to efficiently improve the octane number.

[0039] A mixer 27 is connected downstream of the mixer 24 via a pipe R40, and the bioethanol and reformed gasoline are added in the mixer 24, and the mixed fuel is supplied to the mixer 27 via the pipe R40. An octane number measuring unit 28 that measures the octane number of the mixed fuel is provided in the pipe R40 that connects the mixer 24 and the mixer 27. The octane number measuring unit 28 has a measuring device such as a near-infrared spectrometer, measures the octane number of the mixed fuel flowing through the pipe R40, and outputs the measurement result to a display or a computer 29. The octane number measuring unit 28 may sample the mixed fuel flowing through the pipe R40 and measure the octane number by a combustion test.

[0040] The catalytic reforming unit 26 is further connected to the mixer 24 via a pipe R50, and the reformed gasoline reformed in the catalytic reforming unit 26 is supplied to the mixer 27 via the pipe R50. A regulating valve 26b is provided in the pipe R50 between the catalytic reforming unit 26 and the mixer 27 to regulate the amount of reformed fuel supplied from the catalytic reforming unit 26 to the mixer 27. The regulating valve 26b may be operated manually or may be controlled by a computer 29.

[0041] If the octane number of the mixed fuel measured by the octane number measuring unit 28 does not reach the gasoline standard, the adjusting valve 26b is operated to adjust the amount of reformed gasoline supplied (additional supply amount) so that the octane number of the mixed fuel reaches the gasoline standard. This makes it possible to more reliably adjust the octane number of the mixed fuel to the gasoline standard.

[0042] FIG. 6 is a flow chart showing an example of a gasoline production method according to an embodiment of the present invention. Each step of FIG. 6 may be performed manually or automatically by a computer 29. As shown in FIG. 6, first, in step S1, it is determined whether the olefin content of the mixed fuel measured by the olefin content / octane number measuring unit 25 exceeds the upper limit value. If the result in step S1 is affirmative, the process proceeds to step S2, and if the result in step S1 is negative, the process proceeds to step S3. In step S2, the regulating valves 21a and 22a are operated so as to increase the mixing ratio of FT naphtha that does not contain olefins until the olefin content measured by the olefin content / octane number measuring unit 25 reaches the upper limit value. In step S3, a characteristic map set in advance is referred to, and the amount of bioethanol and the amount of reformed gasoline to be added that correspond to the octane number measured by the olefin content / octane number measuring unit 25 are calculated. In step S4, the regulating valves 23a and 22b are operated so as to add the bioethanol and reformed gasoline in the amounts calculated in step S3 to the mixed fuel. Next, in step S5, it is determined whether the octane number of the mixed fuel to which bioethanol and reformed gasoline have been added, measured by the octane number measuring unit 28, is equal to or higher than a target value. If the result in step S5 is affirmative, the process ends, and if the result in step S5 is negative, the process proceeds to step S6. In step S6, a preset characteristic map is referenced, and the amount of reformed gasoline to be added that corresponds to the octane number measured by the octane number measuring unit 28 is calculated, and the adjusting valve 26b is operated so as to add the calculated amount of reformed gasoline.

[0043] According to this embodiment, the following advantageous effects can be obtained. (1) The device 100 is equipped with a mixer 24 that mixes FT naphtha containing olefins with FT naphtha not containing olefins to achieve a predetermined olefin content (FIG. 5). In this way, by mixing FT naphtha containing olefins with FT naphtha not containing olefins and adjusting the olefin content ratio, gasoline with a desired octane number can be produced from FT naphtha, a renewable fuel with a wide range of properties such as octane number. At this time, the octane number can be efficiently improved due to the synergistic effect when mixing naphtha and olefins (FIG. 2).

[0044] (2) The device 100 is equipped with a first supply section (oxidation prevention processing section 12, storage section 21, adjustment valve 21a) that supplies the crude naphtha obtained by fractionating the FT crude oil synthesized by FT synthesis to the mixer 24 as FT naphtha containing olefins without hydrogenation, and a second supply section (hydrogenation processing section 16, storage section 22, adjustment valve 22a) that hydrogenates the crude naphtha and supplies it to the mixer 24 as FT naphtha not containing olefins (FIGS. 3B and 5). In this way, gasoline can be produced simply and efficiently by using the crude naphtha as a mixed fuel without hydrogenating it as is usually done.

[0045] (3) The first supply section adds an antioxidant to the crude naphtha and supplies it to the mixer 24 as FT naphtha containing olefins (Figures 3A, 3B, and 5). By adding an antioxidant to crude naphtha, which has extremely low oxidation stability, instead of hydrogenating it, it is possible to suppress the loss of olefins due to oxidation and the decrease in octane number.

[0046] (4) The gasoline produced by the device 100 has a naphtha content of 50% or more, an olefin content of 10% or more and 25% or less, and an ethanol content of 20% or less. In this way, by determining the blending ratio within a range in which a synergistic effect is obtained when blending naphtha and olefin, or naphtha and ethanol, the blending ratio of olefin or ethanol to naphtha can be reduced. In addition, by blending olefin preferentially over ethanol, the decrease in calorific value due to the addition of alcohols can be suppressed.

[0047] The above description is merely an example, and the present invention is not limited to the above-mentioned embodiment and modifications, as long as the features of the present invention are not impaired. The above-mentioned embodiment and one or more modifications can be arbitrarily combined, and modifications can be combined with each other. EXAMPLES

[0048] [Example 1] A mixed fuel was prepared by mixing 52% by volume of PRF50 (a 50:50 volume mixture of isooctane and normal heptane) with an octane rating of 50, 10% by volume of ethanol, 18% by volume of diisobutylene, and 20% by volume of toluene. The octane rating of the prepared mixed fuel was 92.5.

[0049] [Example 2] A mixed fuel was prepared by mixing 62% by volume of PRF50, 10% by volume of ethanol, 18% by volume of diisobutylene, and 10% by volume of toluene. The octane number of the prepared mixed fuel was 86.5.

[0050] [Example 3] A mixed fuel was prepared by mixing 80% by volume of PRF65 (an octane number of 65) made by mixing isooctane and normal heptane in a volume ratio of 65:35, 10% by volume of ethanol, and 10% by volume of diisobutylene. The octane number of the prepared mixed fuel was 89.7.

[0051] [Example 4] A mixed fuel was prepared by mixing 90% by volume of PRF80, which is a mixture of isooctane and normal heptane in a volume ratio of 80:20 and has an octane rating of 80, and 10% by volume of ethanol. The octane rating of the prepared mixed fuel was 89.4.

[0052] In Examples 1 to 4, it was confirmed that a mixed fuel equivalent to gasoline standards (about 90) can be prepared by mixing ethanol, diisobutylene, and toluene in appropriate ratios with PRF having an octane number of 50 to 80, which is assumed to be FT naphtha. [Explanation of symbols]

[0053] 10, 10A fractionation section, 11 first distillation column, 12 oxidation prevention processing section, 13, 14 hydrotreating section, 15 second distillation column, 16 hydrotreating section, 20 mixing section, 21, 22, 23 storage section, 21a, 22a, 22b, 23a regulating valve, 24 mixer, 25 olefin content / octane number measurement section, 26 catalytic reforming section, 26a, 26b regulating valve, 27 mixer, 28 octane number measurement section, 29 computer, 100 gasoline production device (device), R10~R12, R20, R30, R40, R50 piping

Claims

1. a mixer for mixing FT naphtha containing olefins and FT naphtha not containing olefins so as to obtain a predetermined olefin content; a first supply section that supplies a crude naphtha obtained by fractionating the FT crude oil obtained by FT synthesis to the mixer as an FT naphtha containing the olefins without hydrogenating the crude naphtha; and a second supply section that hydrogenates the crude naphtha and supplies the crude naphtha to the mixer as FT naphtha not containing the olefins.

2. 2. The gasoline production apparatus according to claim 1, The gasoline production apparatus, wherein the first supply section adds an antioxidant to the crude naphtha and supplies the crude naphtha to the mixer as FT naphtha containing the olefins.

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