JPH05431B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention produces a distillate obtained by fractionating crude oil using a distillation apparatus after mixing a hydroreformed refined oil obtained by hydroreforming and refining crude oil sierre oil in the presence of a catalyst and hydrogen, and petroleum crude oil. This invention relates to a method for refining crude oil sier oil by hydrotreating each fraction separately in the presence of a catalyst and hydrogen. In general, the properties of crude oil sier oil obtained by above-ground carbonization or underground carbonization are different from those of petroleum crude oil, and have a high viscosity and pour point.
Contains large amounts of impurities such as heavy metals and inorganic substances. Furthermore, crude oil siere oil contains large amounts of unsaturated compounds and nitrogen compounds,
It is characterized by the tendency to form gummy substances or precipitates. In particular, crude oil siere oil contains a large amount of nitrogen compounds with a nitrogen content of 0.5 to 3 wt%, so it is difficult to apply hydrotreatment, hydrocracking, catalytic cracking, etc. that are applied in the current oil refining process. In addition, because it is difficult to sufficiently remove nitrogen compounds, hydro-reformed refined oil may become discolored during storage, and gums or precipitates may form. This is one of the obstacles that prevents the introduction of oil shale oil into the current oil refining process. Based on the above, we are considering a method of improving the existing catalyst and hydrorefining equipment and processing crude oil siel oil under conditions more severe than the current hydrorefining conditions to refine it to the same level as current petroleum products. However, in order to achieve sufficient desulfurization, denitrification, and cracking rates through one-stage hydrorefining, high severity is required, and as a result, the catalyst performance deteriorates due to an increase in coke formation rate. In addition, fixed bed reactors have drawbacks such as clogging of the catalyst bed. At the current level of technology such as catalysts and hydrorefining equipment, there are still many technical problems remaining in the first step of hydrorefining to produce products with quality comparable to current petroleum products from crude oil siel oil. Currently, it is difficult to achieve economical and stable long-term operation. As mentioned above, it is difficult to refine crude oil sierre oil, and the carbonization technology comparable to the production cost of petroleum-based crude oil has not been developed, so oil sierre resources have remained largely unused, but in recent years,
From the standpoint of developing petroleum alternative fuels, various attempts have been made to produce and refine crude oil shale oil with the aim of producing products comparable in properties to current petroleum products. As mentioned above, the nitrogen content is 0.5~
It is technically difficult and uneconomical to produce a product with properties comparable to current petroleum products through one-stage hydrorefining of crude oil shale oil, which amounts to 3wt%. A method is being considered in which a refining process is followed by a hydrogenation process or a hydrocracking process in a two- or three-stage process. In this method, it is difficult to reduce the nitrogen content to the same level as that of general petroleum crude oil by treating the crude oil siere oil in the first stage hydrorefining process, and Nitrogen must be denitrified through chemical treatment to a level that meets product standards. For this reason, it is difficult to refine using hydroprocessing equipment designed for the purpose of hydroprocessing each fraction obtained from petroleum crude oil with a low nitrogen content, and it is difficult to modify or operate the hydroprocessing equipment. Forced to change methods. In order to sufficiently denitrify the hydrorefined oil obtained by the first-stage hydrotreating in the second-stage hydrotreating, it is necessary to increase the reaction pressure and reaction temperature or reduce the amount of oil passed. However, the hydrotreated oil obtained in the first stage of hydrorefining contains nitrogen compounds with a structure that is difficult to denitrify, with a nitrogen content of 200 to 200%.
Considering that 20,000 wtppm remains and the thermodynamic equilibrium between nitrogen compounds and their hydrides, it is not desirable to increase the denitrification reaction rate by increasing the reaction temperature, and it is also difficult to maintain the performance of the catalyst. It cannot be said that it is an effective method from a viewpoint.
Furthermore, a particularly important point in the second hydrotreating step is to maintain the sulfur balance of the catalyst system. The sulfur content of the hydrorefined oil obtained through the first stage of hydrorefining is in the range of 50 to 3000 wtppm, which is significantly lower than that of general petroleum crude oil.In particular, the sulfur content of the heavy fraction is lower than that of petroleum crude oil The sulfur content is significantly lower than that of the resulting fractions with the same boiling point range. This becomes more obvious the more you try to achieve a high denitrification rate in the first-stage hydrorefining process, and if the sulfur content of the hydrorefined oil is extremely low, the second-stage hydrorefining process It is difficult to maintain the sulfurized state of the catalyst during the process, and
It is generally known that the cleavage of carbon-nitrogen bonds in nitrogen compounds is promoted by the presence of an appropriate amount of sulfur compounds in the reaction system, making it difficult to fully demonstrate the catalytic performance. As mentioned above, there is a method for producing hydrorefined oil obtained by treating crude oil siere oil alone in the first hydrorefining process to a quality comparable to that of current petroleum products in the second hydrotreating process. , it is necessary to change the equipment and reaction conditions for the second-stage hydrotreating process from the current hydrotreating process equipment and reaction conditions, making it difficult to effectively utilize the equipment installed in the existing refinery. ,
This method has the disadvantage that the cost for refining crude oil shale oil increases due to changes in equipment, catalysts, and reaction conditions. A method that improves the shortcomings of the two-stage processing method for crude oil siere oil described so far, that is, a refining method in which an acid treatment step is installed after the first-stage hydrorefining step to remove nitrogen compounds. Are known. This method uses a mineral acid such as hydrochloric acid or sulfuric acid or an organic solvent such as acetic acid or formic acid instead of the second-stage hydrotreating step, and the hydrorefining process is carried out after the first-stage hydrorefining step. This relates to a method for removing nitrogen compounds remaining in oil, but there is also a known method similar to this method in which a step for adsorption and removal of nitrogen compounds using a cationic ion exchange resin is installed in the second step. ing. Although it is possible to manufacture products comparable in quality to current petroleum products using these methods, it is necessary to regenerate the extraction solvent for removing nitrogen compounds or the cationic ion exchange resin, and from an industrial perspective, the products are difficult to manufacture. There are problems such as a decrease in yield and treatment of recycled waste liquid. In addition, as a method for refining crude oil siel oil, there is a method in which crude oil sier oil is coked by a delayed coking method and then subjected to hydrogenation treatment. The disadvantage was that the yield of liquid product was low due to the generation of coke. Another known method is to hydrorefining crude oil siere oil to reduce the nitrogen content of the hydrorefined oil to an extent that does not impede the performance of the catalytic cracking catalyst, and then catalytically cracking it. The cracking method is a method mainly aimed at producing gasoline, and is not necessarily a method suitable for producing kerosene or light oil. In existing petroleum refining processes, various attempts have been made to produce products that meet current petroleum product standards by processing crude oil shale oil by mixing it with petroleum-based crude oil. Oil and Gas Journal Volume 79 (No. 29) 43 (1981)
The results of test operations conducted at an existing refinery are published in . A first example is naphtha, which is obtained by feeding crude oil siere oil to a fractionating column in a delayed coker that processes petroleum residue fractions.
A production method has been implemented in which jet fuel, light gas oil, and heavy gas oil fractions are each hydrotreated, and the bottom oil is circulated to a delayed coker to produce heavy fuel oil. It has been shown that they tend to form gums or precipitates, and have poor storage stability and thermal stability. It is stated that in order to pass the standards for each fuel oil, it is necessary to further increase the pressure of hydrotreating or to perform clay treatment. As a second example, in the current petroleum refining process, a method is implemented in which 0.1 to 1.0% by volume of crude oil shale oil is mixed with petroleum-based crude oil. Although no effect of mixing crude oil siere oil was observed on properties such as specific gravity and pour point of the distillate obtained by distillation, it was reported that the light oil fraction was colored and a precipitate was formed. There is. In view of the above-mentioned current situation, as a result of intensive research to resolve the shortcomings of the conventional technology regarding a method for refining crude oil siel oil to properties comparable to current petroleum products, we have developed a method for refining crude oil sier oil to a property comparable to that of current petroleum products. Pressure 50-200Kg/ ^cm2 , reaction temperature 300-500
Light naphtha with a nitrogen content of 100wtppm or less, obtained by mixing hydrorefined oil obtained by hydrorefining and refining at ℃ and petroleum crude oil, and then distilling the mixture.
By hydrotreating heavy naphtha of 150wtppm or less, kerosene of 300wtppm or less, gas oil of 700wtppm or less, and vacuum gas oil fraction of 3000wtppm or less in the presence of a catalyst and hydrogen, crude oil sier oil is produced. I finally found a way to purify it. That is, according to the present invention, each fraction obtained by fractionating the hydro-reformed refined oil obtained by treating the crude oil siere oil and the petroleum crude oil in the first stage hydro-reforming refining step is Compared to the method of manufacturing a product by treating the oil separately in the current hydrotreating process and then mixing both types of hydrotreated oil, crude oil with a lower sulfur content is used in the second stage of hydrotreating. By performing a second stage of hydrogenation treatment on each fraction obtained by distilling the mixture of the hydro-reformed refined oil of Sierre oil and petroleum crude oil, we are able to perform processes such as desulfurization, denitrification, and hydrocracking. It becomes possible to maintain a high refining level and at the same time relax the conditions for hydroreforming and refining of crude oil sierre oil, thereby providing an overall stable method for refining crude oil sierre oil. Furthermore, existing equipment can be used effectively without changing equipment, catalysts, or hydrotreating conditions, and it is clear that this is a new invention not found in conventional methods. Next, the configuration of the present invention will be explained in detail. The reactor used in the first hydroreforming refining step in which the present invention is implemented is at least one fixed bed reactor, at least one fluidized bed reactor, or one moving bed reactor. However, depending on the metal content of the crude oil siel oil, the performance of the catalyst, and the hydroreforming refining conditions, a guard reactor or a catalyst whose activity has deteriorated during operation may be extracted and a new catalyst may be supplied. You may install equipment that can do so. The catalyst filled in the reactor is a refractory inorganic oxide such as alumina, silica, alumina zeolite, etc., or a support obtained by mixing these refractory inorganic oxides, and a support obtained from groups of the periodic table such as Ni, Co, and Fe. one or more metals selected from metals and
It is a catalyst obtained by supporting one or more metals selected from group a metals of the periodic table, such as Cr, Mo, and W. These carriers, types of metals, method of combining metals, supported amount, and shape are determined by the properties of the crude oil siere oil and the operating method, but the catalysts packed in the fluidized bed reactor or moving bed reactor are is required to have excellent strength such as wear resistance. In the hydrorefining of crude oil sierre oil in the first-stage hydroreforming refining process, the reaction pressure is generally 50 to 200 Kg/ ^cm2 , especially 100 to 200 Kg/cm2.
The range of 150Kg/ ^cm2 is preferable, and the reaction temperature is 300~
The temperature is 500°C, and a range of 350 to 450°C is particularly preferable. In addition, the feed rate of crude oil sier oil is 0.1
A range of ~2.0 feed volume/catalyst volume/hour is preferred;
Hydrogen is preferably supplied in a range of 2000 to 10000 scf/bb1. When adopting a method of mixing the hydro-reformed refined oil and petroleum crude oil obtained in this manner and then supplying the mixed oil to a distillation apparatus, light naphtha and heavy naphtha obtained by distillation are used. , the nitrogen content of kerosene, gas oil and vacuum gas oil fraction is 100, 150, respectively.
The mixing ratio of the hydro-reformed refined oil and petroleum crude oil is determined so that it is 300, 700 and 3000wtppm or less. As mentioned above, after mixing the hydro-reformed crude oil and petroleum crude oil at a predetermined mixing ratio, the raw material oil for hydrotreating obtained by distillation is used for the subsequent fraction-separated hydrogenation process. It is fed into processing processes and refined to a quality comparable to current petroleum products. Fraction-specific hydrotreatment is carried out in the current petroleum refining process, and the performance of reactors and other equipment installed in each process is comparable to the performance of equipment listed in existing refineries. The performance of the catalyst is also required to be higher than that of existing catalysts. There are optimal conditions for hydrotreating each fraction for each fraction to be treated, but the disadvantage of the low sulfur content of each fraction obtained from hydro-reformed refined oil is that By supplementing by mixing each fraction separately, the sulfurized state of the catalyst is maintained and the denitrification reaction is promoted. Hydrotreated oils that pass the test can be produced. From an industrial perspective, the present invention, which includes new knowledge, can be used to further improve crude oil sier oil, which has a significantly higher nitrogen content than petroleum-based crude oil and which tends to form gums or precipitates. By introducing it into the current petroleum refining process after processing it in the hydrorefining process, it is possible to refine it to a quality comparable to that of current petroleum products, making a significant industrial contribution. . Further, according to the present invention, it is possible to effectively utilize the existing petroleum refining process without modifying it, and in addition, the hydrogenation process obtained by processing crude oil sierre oil in the first stage hydroreforming refining process Compared to the method of treating each fraction from reformed refined oil and petroleum crude oil separately in the current hydrotreating process and then mixing the two hydrotreated oils, denitrification is extremely easy. Moreover, there is no need to add new equipment to the current oil refining process, and manufacturing costs can be reduced. As mentioned above, the method of the present invention makes a significant industrial contribution in the field of fuel oil production. The method of the present invention will be further specifically explained using the following examples, but the method of the present invention is not limited to these examples. In the following, "parts" means "parts by weight" unless otherwise specified. [Example] After filling a boiling bed reactor with the Ni-Mo catalyst shown in Table 1 and carrying out presulfurization and acclimatization, crude oil sier oil having the properties shown in Table 2 was prepared. Hydroreforming and purification at a reaction pressure of 140Kg/cm ² ,
Reaction temperature 400℃, crude oil sier oil feed rate 1.0
The experiment was carried out under the conditions of oil flow volume/catalyst volume/hour and hydrogen ratio of 8000 scf/bb1, and a hydro-reformed refined oil with a nitrogen content of 1070 wtppm was obtained.

【table】

【table】

[Table] 10 parts of this oil sierre oil and 90 parts of Arabian light crude oil whose properties are shown in Table 3.
Fractional hydrogenation treatment was carried out on each fraction obtained by distilling a mixed oil consisting of 1. A fixed bed reactor was filled with the Ni-Mo catalyst shown in Table 4, and after presulfiding and acclimatization were carried out, the above-mentioned fractions were separated into fractions under the conditions shown in Table 5. Hydrogenation treatment was performed. Table 6 shows the results of the hydrotreatment for each fraction.

【table】

【table】

【table】

【table】

【table】

【table】

[Table] Yield of mixed crude oil for mixed oil As a comparative example, the results are shown in which each fraction obtained from hydro-reformed refined oil and Arabian light crude oil was hydrotreated individually without being mixed, and then mixed. . Comparative Example 1 in Table 7 shows the results of a method in which hydrotreated refined refined oil and heavy naphtha fraction obtained from Arabian Light crude oil were individually hydrotreated and then mixed. The nitrogen content of the mixture significantly exceeds the permissible value for catalytically reformed feedstocks, demonstrating the superiority of the process according to the invention.

[Table] Hydrogenated reformed refined oil Heavy naphtha hydrogenated oil + Arabian la
Comparative Example 2 in Table 8 shows the results of a method in which hydrotreated heavy naphtha hydrotreated oil, hydrotreated refined refined oil and kerosene fraction obtained from Arabian light crude oil were each individually hydrotreated and then mixed. However, due to the high nitrogen content, the hydrotreated oil mixture turned yellow-brown in color and the formation of precipitates was observed. Therefore, it is clear that the method according to the present invention is superior.

[Table] Hydrogenated reformed refined oil Kerosene fraction Hydrotreated oil + Arabian Rye
Comparative Example 3 in Table 9 shows the results of a method in which the hydrogenated reformed refined oil and the light oil fraction obtained from Arabian Light crude oil were each individually hydrotreated and then mixed. However, the hydrotreated oil mixture turned brown due to the high nitrogen content, and the formation of precipitates was observed. Therefore, it is clear that the method according to the present invention is superior.

[Table] Hydrogenated reformed refined oil, gas oil distillate, hydrogenated oil + Arabian Rye
Gas oil fraction hydrotreated oil The above results show that the method of the present invention is an effective method for improving the quality of crude oil shale oil to a level comparable to that of current petroleum products.

Claims (1)

[Claims] 1 Crude oil sier oil in the presence of a catalyst and hydrogen at a reaction pressure of 50 to 200 Kg/cm ² and a reaction temperature of 300 to 500
Light naphtha with a nitrogen content of 100wtppm or less, heavy naphtha with a nitrogen content of 150wtppm or less, obtained by mixing hydroreformed refined oil obtained by hydroreforming and refining at ℃ and petroleum crude oil, and then distilling the mixture. Kerosene below 300wtppm, diesel oil below 700wtppm and
1. A method for refining crude oil siel oil, which comprises hydrotreating vacuum gas oil fractions of 3000wtppm or less in the presence of a catalyst and hydrogen.