JP2006257442A - Process for removal of salt, catalytic reforming method and catalytic reforming apparatus using the process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an effective removal process of a salt contained in a hydrocarbon oil. <P>SOLUTION: The method for removal of a salt is characterized by filtering a hydrocarbon oil containing the salt through a filter at ≤120°C substantially in the absence of water to trap the salt with the filter, separation and washing of the filter with water to dissolve and remove the trapped salt and reuse of the salt free filter for the removal of the salt in the hydrocarbon oil. The present invention also relates to a catalytic reforming method and apparatus using aforementioned method for removal of the salt. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for removing a salt in a hydrocarbon oil, and more particularly, to a salt removing method for efficiently removing a salt such as ammonium chloride from a hydrocarbon oil with very simple equipment. The present invention also relates to a catalytic reforming apparatus and a catalytic reforming method using such a salt removal method.

  In petroleum refining processes and petrochemical processes, distillation separation operations using distillation towers are widely used to produce various petroleum products and semi-finished products. However, if salts are contained in the raw material oil to the distillation tower, the salts are deposited as solids in the distillation tower and deposited or adhered to the internals of trays, etc. May cause a malfunction. This is because the entrained salt is concentrated in the process of moving through the distillation tower, and further reaches the site of conditions such as temperature, pressure, flow rate, etc. that are convenient for salt precipitation, and precipitation is promoted. It is believed that deposition or adhesion occurs. A typical salt that causes troubles in oils processed in processes such as petroleum refining is ammonium chloride. Salts such as ammonium chloride do not become solid at high temperatures, but become solid at low temperatures and cause various troubles.

  In this way, the salt is deposited in a place that satisfies the precipitation conditions, particularly when the temperature is lowered. Therefore, the salt is not limited to the distillation tower, and piping and heat exchangers are blocked, and rotation of a rotary machine such as a pump / compressor is caused. Cause trouble. In extreme cases, it is also necessary to suspend the operation of the equipment, and even the entire process, to remove salt deposits. This is a significant loss for equipment industries such as petroleum refining and petrochemistry, which are usually premised on continuous operation for one year or longer.

  In recent years, in the petroleum refining industry, a catalytic reformer equipped with a continuous catalyst regeneration device has been widely adopted as a naphtha catalytic reformer. This continuous catalyst regeneration type catalytic reformer always supplies a fresh catalyst (regenerated catalyst) to the reforming reactor, and sequentially flows it to a plurality of reactors to send the deteriorated catalyst to the catalyst regeneration system. Also in the system, regeneration is continuously performed, and the catalyst whose activity is restored is supplied again to the reforming reactor. At this time, the reforming catalyst is treated with a chlorine compound during catalyst regeneration in order to adjust the activity. The chlorine content of the chlorine compound enters the reforming reactor together with the regenerated catalyst. In the reforming reactor in a hydrogen atmosphere and high temperature, the chlorine content is accompanied by impurities in the naphtha feed or the like, or the basic compound and salt produced in the reforming reactor atmosphere are generated, and the catalytic modification is performed. It flows out of the reactor together with quality oil. The salt does not become a solid at high temperature, but is cooled and solidified at a temperature of 120 ° C. or lower, followed by a distillation column such as a stabilizer or debutizer, a pipe or a heat exchanger, and a rotary machine such as a pump / compressor. In this case, it precipitates and causes the above troubles.

As a method for removing salts in oil, there is a method in which a process fluid (hydrocarbon oil) and water or a caustic soda aqueous solution are mixed and a salt contained in the process fluid is transferred to the water or caustic soda aqueous solution side to be removed. Although this method is expected to have a removal effect, it requires water or caustic soda aqueous solution injection equipment, oil and water or caustic soda aqueous solution mixing equipment, oil and water or aqueous solution separation equipment, wastewater treatment equipment, etc. Since a trace amount of water is mixed in the process fluid at the time of cleaning, if the device whose performance is affected by the water is downstream, additional measures for thorough water removal are required.
As a salt removal method similar to the washing method, JP-A-2000-96067 discloses a hydrocarbon oil containing water-soluble salts for introducing water into a distillation column in order to remove the salts accumulated in the distillation column. A distillation method is disclosed. In this method, water injection equipment, oil and water separation equipment need to be expanded or strengthened, and if the subsequent hydrocarbon treatment process dislikes moisture, the same as in the above washing method, There is a problem that trace moisture must be removed.

  Japanese Patent Laid-Open No. 2001-72984 discloses (a) zinc oxide, (b) a binder, and (c) at least one alkali (earth) to remove inorganic and organic chlorine compounds in a liquid hydrocarbon fluid. Class) A chlorine compound removing agent containing a metal compound as a main component and a removing method using the same are disclosed. In the present invention, the chlorine compound is removed and the generation of the organic chlorine compound is suppressed to extend the period until the chlorine leak. However, as shown in the examples of the present invention, the chlorine compound removing agent is an adsorbent, and therefore, when a certain amount of chlorine compound is adsorbed, more chlorine compound leaks without being adsorbed. Therefore, it is necessary to replace the adsorbent before leaking, but it is extremely difficult to predict (that is, the life expectancy of the adsorbent), and it is not possible to use the adsorbent without waste for planned periodic repairs. It's impossible. Furthermore, in the method using an adsorbent, naturally, it is necessary to add a chlorine compound removal facility filled with the adsorbent, and purchase and replace an expensive adsorbent every time periodic repairs are performed. There are also problems such as having to dispose of in consideration of the next pollution.

  An object of the present invention is to solve the above problems, and to provide a salt removal method for effectively removing a salt such as ammonium chloride in a hydrocarbon oil with an extremely simple and easy-to-operate facility. And Another object of the present invention is to provide a naphtha catalytic reforming apparatus and catalytic reforming method using the salt removal method.

The present inventors have examined the cause of operation failure in the distillation column following the reforming reactor, and found that this cause is due to salt precipitation, particularly ammonium chloride precipitation.
Although the details of the salt precipitation mechanism are not clear, an organic chlorine compound injected during regeneration to adjust the activity of the reforming catalyst and an organic nitrogen compound derived from the raw material oil, etc. In which hydrogen chloride and ammonia are produced under the high temperature and hydrogen atmosphere, and they react to form a salt, which is locally precipitated as a salt solid (ammonium chloride crystal) as the temperature decreases. It is guessed. In particular, the problem with distillation towers is that salt concentration in the distillation tower, growth of salt solids (crystals) as the temperature decreases, oil flow rate, and other conditions promote the formation of large salt solids. Presumed to be deposited and deposited at a certain part of the distillation tower.

Furthermore, the present inventors have found that this salt exists in a hydrocarbon oil in a solid state under a certain condition and can be easily filtered off by a filter, and the present invention has been reached.
That is, the gist of the present invention that solves the above problems is as follows.
(1) The salt-containing hydrocarbon oil is filtered through a filter at a temperature of 120 ° C. or less in an atmosphere substantially free of water, the salt is captured by the filter, and the filter is separated and washed with water. And removing the trapped salt and reusing the filter from which the salt has been removed to remove the salt in the hydrocarbon oil.
(2) The method for removing a salt according to the above (1), wherein the salt is ammonium chloride.
(3) The method for removing a salt according to the above (1) or (2), wherein the hydrocarbon oil is a naphtha catalytic reformed oil before distillation.
(4) The salt removal method according to any one of (1) to (3), wherein the filtration is performed using a filter having an opening of 0.1 to 20 μm.

(5) In a catalytic reformer for catalytically reforming naphtha, between the catalytic reforming reactor and a distillation column for removing light components contained in the catalytic reforming oil flowing out from the catalytic reforming reactor And a filter for removing the salt in the catalytic reforming oil by filtering the catalytic reforming oil at a temperature of 120 ° C. or less in an atmosphere substantially free of water.
(6) In the catalytic reforming method for catalytically reforming naphtha, between the catalytic reforming reactor and a distillation column for removing light components contained in the catalytic reforming oil flowing out from the catalytic reforming reactor A catalytic reforming method in which a filter is provided on the catalytic reforming oil and the catalytic reforming oil is filtered at a temperature of 120 ° C. or less in an atmosphere substantially free of water to remove salts in the catalytic reforming oil.

  The present invention is a method for removing a salt in a hydrocarbon oil by filtering a hydrocarbon oil containing a salt at a temperature of 120 ° C. or less in an atmosphere substantially free of water. The salt can be efficiently removed from the hydrocarbon oil. Therefore, troubles due to salt precipitation such as blockage of a tray of a subsequent distillation facility, blockage of a pipe or a heat exchanger, drive failure of a rotary machine such as a pump / compressor, and the like can be avoided.

  Examples of the hydrocarbon oil containing a salt referred to in the present invention include a hydrocarbon oil containing a salt such as ammonium chloride which precipitates at a temperature of 120 ° C. or less, a refined oil containing a salt derived from crude oil or a raw oil, and a petroleum distillate. For example, a spilled oil of the process containing a salt generated in a process for treating a minute or a petrochemical process. Specifically, in a catalytic reformer, particularly in a catalytic reformer equipped with a continuous catalyst regeneration device, catalytic reformed oil flowing out from the catalytic reforming reactor, naphtha or kerosene distilled from the atmospheric distillation unit And hydrodesulfurized oil obtained by hydrodesulfurizing distillate such as reduced pressure gas oil distilled from a vacuum distillation apparatus.

  That is, the present invention provides a salt such as ammonium chloride for filtering a hydrocarbon oil containing a salt, such as catalytic reforming oil, hydrodesulfurized oil, etc., at a temperature of 120 ° C. or less in an atmosphere substantially free of water. It is a method of removing. Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 and 2 with a catalytic reformer for catalytically reforming naphtha as a representative. It is not limited to. FIG. 1 shows a catalytic reforming apparatus as one embodiment of the present invention, and FIG. 2 shows a conventional catalytic reforming apparatus. 1 and 2, the same equipment is given the same reference numerals.

  In FIG. 2, the raw material naphtha (desulfurized naphtha) of the catalytic reformer is supplied to the reforming reactor 1 as a feed 7 mixed and heated with recycled hydrogen. In the reforming reactor 1, the naphtha is catalytically reformed with hydrogen gas and a regenerated catalyst 13 continuously supplied from the regeneration system at a high temperature. In FIG. 2, the reforming reactor is shown by only one unit as reference numeral 1, but usually there are three or four units, and a mixture of naphtha and hydrogen (feed 7) is provided between the three or four reactors. The temperature is adjusted in the heating furnace, and the reforming is performed by sequentially passing through each reactor. The catalyst also sequentially passes through the reactor to become a deteriorated catalyst 14, is sent to a regeneration system (not shown), is regenerated, recovers its activity, and is supplied again to the reforming reactor 1 as a regenerated catalyst 13. The catalytic reformed oil 8 flowing out from the reforming reactor 1 is cooled by the cooler 2 and sent to the separation tank 3 and flows out as a hydrogen-rich light gas 10 and a catalytic reformed oil 9 from which the light gas 10 is separated. To do. Usually, a part of the light gas 10 is used as recycled hydrogen. The catalytic reforming oil 9 is heated by the heater 4 and sent to a distillation column 5 such as a stabilizer or a debutizer to be distilled. A light reformed fraction 12 of light gas or liquefied petroleum gas (LPG) or less flows out from the top of the distillation column 5, and a catalytic reformed oil whose vapor pressure is adjusted or light fraction of LPG or less is separated from the bottom of the column. 11 flows out. The catalytic reforming oil 11 is used as a gasoline base material or as a petrochemical raw material for recovering aromatic components and producing chemical products.

FIG. 1 shows an embodiment of the present invention, which is a catalytic reformer equipped with a filter 6 before heating the catalytic reforming oil 9 with the heater 4 to supply the distillation column 5. .
As already mentioned, the chlorine component derived from the chlorine compound injected to adjust the catalyst activity is introduced into the reforming reactor together with the regenerated catalyst and converted to hydrogen chloride in the reforming reactor in a high-temperature hydrogen atmosphere. Is done. On the other hand, naphtha uses highly hydrodesulfurized desulfurized naphtha as a raw material of the catalytic reformer, but contains a trace amount of nitrogen compound, and the nitrogen content is converted into ammonia in the reforming reactor. Hydrogen chloride and ammonia produced in the reforming reactor are cooled and deposited as ammonium chloride salts. The chlorine and ammonia components that enter the reactor are not necessarily introduced in salt-forming equivalents, and are generally in excess of chlorine. Chlorine content is not preferable because it may corrode equipment materials as hydrogen chloride or chloride ions, but the solidified and precipitated salts are deposited and deposited exclusively in the subsequent equipment, especially the distillation tower 5, causing clogging and malfunction. It also causes problems such as.

  Therefore, in the present invention, the temperature of the catalytic reforming oil 9 that has been cooled down and separated from the hydrogen-rich light gas after flowing out of the catalytic reactor 1 is 120 ° C. or less before being supplied to the distillation column. Filter. That is, in the present invention, as shown in FIG. 1, a filter 6 not provided in the conventional catalytic reforming apparatus is installed, and at least a part of the catalytic reforming oil 9 after light gas separation is filtered through the filter 6. It is. By doing so, a salt such as ammonium chloride in the catalytically modified oil is captured by the filter 6, and problems such as malfunction of the distillation column 5 due to salt precipitation / deposition in the distillation column 5 are eliminated.

  When the temperature exceeds 120 ° C., the precipitation of solid salt is small, and the amount of salt (or hydrogen chloride and ammonia) that passes through without being trapped by the filter increases. The lower the temperature, the better the salt precipitates out and is captured by filtration, but the temperature must be raised in the subsequent distillation step, so it should be determined taking into account the energy balance of the entire device or refinery. The filtration temperature is preferably 100 ° C. or lower, particularly 50 ° C. or lower. When the temperature of the hydrocarbon oil exceeds 120 ° C., the temperature may be adjusted to the above temperature using a known appropriate method.

  In the present invention, the hydrocarbon oil is filtered under an atmosphere substantially free of moisture. That is, in the present invention, the filtration of the hydrocarbon oil is performed without adding water such as water and water vapor from the outside of the system, which means that the hydrocarbon oil such as the contact reforming oil is directly filtered. That is, the hydrocarbon oil is not filtered in the form of a mixture with at least saturated or higher moisture and may contain less than saturated moisture. The amount of water dissolved in the hydrocarbon oil is preferably less than saturation at normal temperature (10 to 25 ° C.), and preferably 50 ppm by weight or less when the hydrocarbon oil is a catalytically modified oil. Therefore, since the hydrocarbon oil from which salt has been removed by the method of the present invention is substantially free of moisture, there is no need to give special consideration to the process that dislikes the subsequent water. In contrast, there is no need for oil / water separation, and water having a large latent heat is not heated and cooled, which is advantageous in terms of energy.

  As the filter used for the filtration of the present invention, any filter such as a nonwoven fabric filter, a sintered filter, and a hollow fiber membrane filter can be used as long as salts can be removed. Since a filter of a type in which a pleated type cartridge in which a flat membrane is folded is accommodated in a casing is compact and can be subjected to a large amount of filtration processing, it can be preferably used particularly when processing petroleum products handled in bulk.

  Examples of the filter material include polytetrafluoroethylene, polyethylene, polypropylene, polycarbonate, polyester, polyamide, polyimide, polysulfone, acrylic, cellulose ester, glass fiber, metal, and paper. When selecting filter materials, some hydrocarbon oils, such as catalytically modified oils that contain a large amount of aromatic components, may dissolve or swell, so the target oil type, its temperature, and pressure must be selected in advance. It is preferable to appropriately select the material under consideration of the use conditions such as the above. For example, since plastics such as polyethylene and polypropylene may be swollen in such applications, it is preferable to avoid them or use those that have been treated for swelling by surface treatment or the like.

  The opening of the filter is preferably 0.1 to 20 μm in order to capture salts efficiently. For filters with a size of less than 0.1 μm, the differential pressure increases, and after passing the oil, the time until the filter differential pressure rises to the allowable differential pressure of the filter is shortened. It is not practical because it must be frequently removed by washing. When the size exceeds 20 μm, there is too much salt passing through the filter without being trapped, and it makes no sense to install the filter. The mesh opening is more preferably 1 to 10 μm, and particularly preferably 1 to 5 μm.

  Specifically, when a filter is installed in a catalytic reformer, as shown in FIG. 1, the filter is a flow path (pipe) between the reactor 1 and the first distillation column where the temperature of the catalytic reforming oil is 120 ° C. or less. For example, it is preferable to install in the flow path of the contact reforming oil 9 flowing out from the separation tank 3 of the recycled hydrogen gas. If there is no place at a temperature of 120 ° C. or lower, the temperature of the contact reformed oil may be lowered to 120 ° C. or lower by a known method such as passing through a cooler (cooling heat exchanger) and passed through a filter. In addition, the filter may be provided so that the total amount or at least a part of the catalytic reforming oil, for example, 10 to 90% of the oil flow rate passes through the filter. In this way, the filter size can be reduced by limiting the amount of oil passed through the filter so as to capture the minimum amount of salt that can avoid the malfunction of the distillation column.

A filter is a facility that does not require complex control and does not require special skill to operate. As salt is captured by the filter, the filter differential pressure increases. When the maximum pressure difference allowed by the design of the filter is reached, oil passing is stopped and the filter whose differential pressure has reached the upper limit is disconnected from the oil system.
Usually, since salts such as ammonium chloride are water-soluble, salts captured by passing water through a filter can be dissolved and removed in water. The filter may be washed by passing water continuously through the filter, or once or two batch washings in which the filter casing is filled with water and held for a certain period of time to dissolve and drain the salt. You may carry out by repeating more than once. The direction in which water is passed through the filter may flow in the direction through which the contact reforming oil is passed, or may flow in the opposite direction to the oil. Alternatively, the salt can be removed by opening the filter casing, extracting the cartridge, and washing with water outside.
After washing with water, moisture is removed by passing dry air through the filter, then the filter is connected to an oil system and contact reformed oil is passed. The filter returns to an almost fresh state and can be used repeatedly.

  In addition, two or more filters may be provided in parallel in the hydrocarbon oil flow path so that oil passing and washing (and waiting) are repeated in cooperation with each other, or one filter is provided in the hydrocarbon oil flow path. Only when the filter is washed with water, the entire amount of the hydrocarbon oil may be passed through the bypass of the filter (conventional hydrocarbon oil passage). In any case, the salt can be removed without stopping the operation of the hydrocarbon treatment apparatus.

In the above description, an example in which the salt removal method of the present invention is applied to a naphtha catalytic reformer in the oil refining industry has been described focusing on a catalytic reformer equipped with a continuous catalyst regeneration device. Since it can be applied as long as it contains hydrocarbon oil, it can also be applied to a fixed bed type catalytic reformer with or without a catalyst regeneration device. Furthermore, the present invention can be similarly applied to the case of removing a salt from a hydrocarbon oil containing a salt in other petroleum refining processes or petrochemical processes.
For example, naphtha is always desulfurized in order to remove sulfur contained as impurities before being processed in the catalytic reformer. This desulfurization treatment is usually a hydrodesulfurization treatment, and the sulfur compound as an impurity is converted into a hydride (mainly H ₂ S) and separated and removed. In this case, the nitrogen compound in the raw naphtha as the raw material to be desulfurized is also hydrogenated to produce ammonia. Ammonia reacts with chlorine etc. brought into the system as impurities in crude naphtha and recycled hydrogen to produce salts such as ammonium chloride. The salt removal method of the present invention can also be applied to hydrodesulfurized naphtha containing such a salt, and the salt can be effectively removed.

  In the method of the present invention, salt can be removed simply by providing a filter in the flow path of hydrocarbon oil. Therefore, conventional water washing or soda washing, introduction of water into a distillation column, method using an adsorbent, etc. Compared with, the equipment is simple and economical, there is no need to worry about secondary pollution, and no skill is required for operation.

  Next, the present study will be described in more detail based on examples. Here, although the test performed using the catalytic reforming apparatus is shown, the present invention is not limited by the examples.

As shown in FIG. 1, in an actual catalytic reforming apparatus, a filter 6 in which a pleated type cylindrical filter cartridge is mounted on a casing in an outlet pipe of a separation tank 3 that separates a hydrogen rich gas 10 and a catalytic reforming oil 9. Was installed, and a certain amount of the catalytic reforming oil 9 was passed through a filter, and a test for removing ammonium chloride in the catalytic reforming oil was conducted.
The concentration of ammonium ions and chlorine ions in the catalytic reforming oil varies depending on the feedstock oil and the amount of chlorine injected to adjust the catalyst activity, but the chlorine ion is usually about twice the ammonium ion by weight ratio. It is included at a rate of more than that. It can be said that the production of ammonium chloride is governed by the amount of ammonium ions. The removal effect of ammonium chloride by the filter was evaluated by measuring the ammonium ion concentration and the chlorine ion concentration in the contact reformed oil sample collected from the inlet and outlet of the filter by the following method.

(Concentration measurement method)
500 ml of the contact reformed oil sample was placed in a separatory funnel, 50 ml of pure water was added and sealed, and shaken vigorously for 5 minutes. Thereafter, the mixture was allowed to stand for 5 minutes to separate the aqueous layer and the oil layer, and the concentrations of ammonium ions and chlorine ions in the obtained aqueous layer were measured using ion chromatography. The obtained measured values of ammonium ion and chlorine ion were converted to the contact reformed oil standard, and the ammonium ion concentration and the chlorine ion concentration in the contact reformed oil were determined.

Example 1
A filter having the specifications shown in Table 1 as Example 1 was used, and contact reforming oil (pressure 3.4 MPa, temperature 35 ° C.) was allowed to flow therethrough at a flow rate of 5 kl / hr, and the filter differential was an allowable differential pressure of 0. When the pressure reached 3 MPa, the supply of catalytic reforming oil was stopped. After stopping the supply of the catalytic reforming oil, the filter casing was opened and the filter cartridge was taken out. The filter cartridge was put in a metal container having a capacity of about 20 l, and pure water was poured to immerse the entire filter cartridge, and then drained. .
This operation is repeated 4 times, and the ammonium chloride is washed and removed. Then, the water is injected for the fifth time, and the filter cartridge is completely immersed for 1 hour to dissolve ammonium chloride deep in the filter medium sufficiently. Drained. The washed filter cartridge was dried in a drying chamber at about 30 ° C. for 24 hours, and then the filter cartridge was set in the casing and contact reformed oil was passed again. In this way, the operation of contact reforming oil passing and filter washing was repeated 6 times.
Sample the contact reformed oil at the filter inlet and outlet at the start of oil flow, at the time of oil flow stop and at the second day after the start of oil flow, and measure the ammonium ion concentration and chlorine ion concentration in each sample oil by the above method. The removal effect of ammonium chloride was evaluated.

  As a result of this test, the contact-modified oil could be passed through the filter without any particular problem during the first to sixth oil passage periods (total 683 hours). The ammonium ion concentration and the chlorine ion concentration in the sample oil at the filter inlet and outlet were measured over the entire oil passage period (n = 18), and numerical values obtained by arithmetic averaging are shown in Table 2. As shown in Table 2, ammonium ions were not detected in the sample oil at the filter outlet over the oil passing period. The amount of decrease in the chlorine ion concentration substantially corresponds to the equivalent amount of chlorine ions that form ammonium chloride with the ammonium ions contained in the contact reforming oil at the filter inlet. Therefore, it can be seen that almost all of the ammonium chloride contained in the contact reformed oil can be removed by the filter.

(Example 2)
Evaluation was performed in the same manner as in Example 1 except that an acrylic filter having the specifications shown in Table 1 as Example 2 was used. The ammonium ion concentration and the chlorine ion concentration (arithmetic average value over the entire oil passing period) are shown in Table 2 as in Example 1.
As a result, during the first to sixth oil passage periods (total of 534 hours), the contact reformed oil can be satisfactorily passed without any particular problems, and almost all ammonium chloride in the contact reformed oil is removed by the filter. We were able to.

(Reference example)
In the catalytic reforming apparatus shown in FIG. 2 in which the filter of the present invention is not installed, inconvenience due to precipitation of ammonium chloride was observed in the distillation column 5 downstream of the separation tank 3 due to long-term continuous operation.

  As described above, the present invention is a method for removing salt in hydrocarbon oil that is filtered at 120 ° C. or lower in an atmosphere substantially free of water, and salt can be reliably removed with simple filtration equipment. In addition, troubles in purification equipment such as distillation towers due to salt precipitation can be prevented, and unlike conventional methods using water and adsorbents, the equipment is simple and economical, and requires no skill in operation. It has the effect of.

It is a flowchart which shows one Embodiment of this invention which installed the filter in the catalytic reforming apparatus. It is a flowchart which shows the conventional catalytic reforming apparatus which does not comprise a filter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Catalytic reforming reactor 5 ... Distillation tower 6 ... Filter 9 ... Catalytic reforming oil (after light gas separation)

Claims (6)

  Hydrocarbon oil containing salt is filtered through a filter at a temperature of 120 ° C. or less under a substantially water-free atmosphere, the salt is captured by the filter, and the filter is separated and washed with water, captured. A method for removing a salt in a hydrocarbon oil, wherein the salt removed is dissolved and the filter from which the salt has been removed is reused for removing the salt in the hydrocarbon oil. The method for removing a salt according to claim 1, wherein the salt is ammonium chloride. The method for removing a salt according to claim 1 or 2, wherein the hydrocarbon oil is a naphtha catalytic reformed oil before distillation. The salt removal method according to any one of claims 1 to 3, wherein the filtration is performed using a filter having an opening of 0.1 to 20 µm. In a catalytic reforming apparatus for catalytically reforming naphtha, a substantial difference between a catalytic reforming reactor and a distillation column for removing light components contained in the catalytic reforming oil flowing out from the catalytic reforming reactor, A catalytic reforming apparatus characterized by comprising a filter for removing the salt in the catalytic reforming oil by filtering the catalytic reforming oil at a temperature of 120 ° C. or less in an atmosphere free of water. In the catalytic reforming method for catalytically reforming naphtha, a filter is provided between the catalytic reforming reactor and a distillation column for removing light components contained in the catalytic reforming oil flowing out from the catalytic reforming reactor. A catalytic reforming method comprising removing the salt in the catalytic reforming oil by filtering the catalytic reforming oil at a temperature of 120 ° C. or lower in an atmosphere substantially free of water.