JP4409977B2 - Waste oil treatment method in oil refining - Google Patents

Description

  The present invention relates to a method for treating waste oil (slop oil) generated in a petroleum refining process.

  FIG. 2 shows an outline of an example of a typical oil refining process conventionally performed.

  As shown in FIG. 2, in the oil refining process, the crude oil in the crude oil tank 100 is usually fed to the atmospheric distillation column 103 through the crude oil desalting apparatus 101 and the heating furnace 102, and is sent to the atmospheric distillation column 103. , Naphtha, kerosene, light oil, etc. are fractionated for each fraction, and heavy oil is separated as residual oil. Subsequently, the said fraction and residual oil are made into petroleum products through the process process in the processing apparatus 200 arrange | positioned downstream of the atmospheric distillation tower 103. FIG.

  Further, in such a petroleum refining process, waste oil generated from the crude oil desalting apparatus 101, mixed oil generated when the apparatus is switched, and off-spec (non-standard) products are used as waste oil (slop oil) in a slop tank. Collected in 300 and processed.

At present, slop oil generated in such refineries is accepted in one slop tank 300 without distinguishing heavy and light distillation properties, and thereafter, this slop oil is removed from the slop tank 300 by crude oil removal. It is sent to the salt device 101 and fractionated for each fraction together with the crude oil, and then sent to the processing device 200 of the next step for processing. In general, slop oil is processed in the same manner as crude oil and residual oil.
JP-A-5-222374 Special table 2003-511546 gazette

  According to the results of studies and experiments conducted by the present inventors, according to the distillation properties of a certain slop oil, a light fraction having a distillation temperature (EP) of 360 ° C. or lower is about 90% by volume, and a heavy fraction having a distillation temperature of 360 ° C. or higher. The fraction was 10% by volume, most of which was lighter than the light oil fraction.

  As the product properties will require severe management due to the planned zero-sulfurization and ultra-deep desulfurization in the future, the amount of off-spec products is expected to increase. Is likely to increase.

  From the above viewpoint, the present inventors do not have such a bad property that the light component in the slop oil has to be returned to the atmospheric distillation column 103. Therefore, the heavy component and the light component are not included. In other words, the heavy component can be returned to the atmospheric distillation column 103 and the light component can be returned to the processing apparatus 200 downstream of the atmospheric distillation column 103.

  The present invention has been made on the basis of the novel findings of the present inventors.

  The objective of this invention is providing the processing method of the waste oil in the petroleum refining process which can reduce the fuel of an atmospheric distillation tower, as a result, aim at energy saving, and also reduce the discharge | emission amount of a carbon dioxide.

The above object is achieved by the method for treating waste oil in petroleum refining according to the present invention. In summary, the present invention separates crude oil into a residual oil and at least one fraction in an atmospheric distillation tower, and then the fraction and the residual oil are arranged downstream of the atmospheric distillation tower. In a waste oil treatment method for treating waste oil generated in an oil refining process for further processing in a treated apparatus to produce a petroleum product,
Separate tanks for residual oil waste oil and tanks for light waste oil are installed separately.
The residual oil waste oil generated in the residual oil treatment process for treating the residual oil is received in a tank dedicated to the residual oil waste oil, and sent to the atmospheric distillation tower through the crude oil desalting apparatus and the heating furnace together with the crude oil, and processed.
A waste oil treatment method characterized in that light waste oil generated in a light treatment step for treating the fraction is received in a tank dedicated to light waste oil, and returned to the raw oil treatment step or the light treatment step as a raw material. .
According to one embodiment of the present invention, waste oil generated in the oil refining process, waste oil fraction produced from crude oil desalter, a混油or off-spec products generated when switching device.

According to another embodiment of the present invention, the processing step of returning the light waste oil is a step of processing the heaviest fraction of the light processing steps of processing the fraction , or a step of processing the residual oil. It is said. Here, the step of treating the residual oil can be a step of treating a distillate obtained by vacuum distillation of the atmospheric residual oil.

According to another embodiment of the present invention, the step of processing the heaviest fraction among the light processing steps of processing the fraction is a step of processing the light oil fraction.

According to another embodiment of the present invention, the 90% distillation temperature of the light waste oil may be 320-420 ° C.

According to another embodiment of the present invention, the light treatment step is a hydrorefining, catalytic reforming or catalytic cracking step for treating a fraction containing naphtha, gasoline, kerosene or light oil as a main component. ,
The residual oil treatment step includes (1) vacuum distillation, hydrorefining, thermal decomposition or catalytic cracking of atmospheric residual oil, (2) hydrorefining, thermal cracking or catalytic cracking of vacuum residual oil, or (3) This is a process of hydrorefining, hydrocracking, thermal cracking or catalytic cracking of distillate by distillation under reduced pressure of atmospheric residue.

  According to the present invention, the slop oil (waste oil) generated in the petroleum refining process is distinguished into residual oil slop oil and light slop oil, and the light slop oil processes the fraction arranged downstream of the atmospheric distillation tower. The fuel can be reduced by reducing the processing amount of the atmospheric distillation tower by directly feeding it into the light processing equipment. As a result, energy saving can be achieved, and at the same time, carbon dioxide emissions can be reduced.

  Hereinafter, the method for treating waste oil in petroleum refining according to the present invention will be described in more detail with reference to the drawings.

Example 1
FIG. 1 shows an overview of one embodiment in a typical oil refining process.

  In the oil refining process shown in FIG. 1, crude oil is continuously supplied from the crude oil tank 100, and desalting, dehydration, and solid content removal are performed by the crude oil desalting apparatus 101. The crude oil leaving the crude oil desalting apparatus 101 is further heated to an appropriate temperature in the heating furnace 102 and fed to the atmospheric distillation tower 103.

  Next, in the atmospheric distillation tower 103, the gas is recovered, and fractions such as naphtha, kerosene, and light oil are distilled, and heavy oil that does not distill is separated as residual oil. These distillates and residual oil are sent to the processing apparatus 200 for processing, and the final petroleum product is obtained.

  That is, according to the present embodiment, LPG is recovered from the gas component by the gas recovery device 201, and LPG is made into a product. The naphtha is directly used as a petrochemical raw material, subjected to desulfurization treatment by the naphtha hydrorefining device 202, and further reformed by the catalytic reforming device 203 and used for blending gasoline. The kerosene component is desulfurized in the kerosene hydrorefining device 204, and the sulfur and nitrogen components are removed as product kerosene, or refined naphtha is blended into jet fuel.

  Some diesel oil components are used as diesel oil as they are, but many are desulfurized by diesel oil hydrorefining device 205 to remove diesel sulfur diesel diesel oil.

  The residual oil may be used as heavy oil as it is, and if necessary, it is blended into product heavy oil such as C heavy oil by desulfurization using a direct desulfurization apparatus, excluding sulfur.

  In addition, the residual oil is distilled under reduced pressure in a vacuum distillation apparatus 206, and separated into a vacuum gas oil that does not contain residual oil and a vacuum residual oil that is a residual oil. The obtained vacuum gas oil is converted into a vacuum desulfurized gas oil that has been desulfurized by the indirect desulfurization device 207, and this vacuum desulfurized gas oil is decomposed by the catalytic cracking device 208 to produce cracked gasoline. Cracked gasoline is blended into product gasoline. The vacuum desulfurized gas oil is blended with A heavy oil.

  Further, the reduced pressure residual oil is directly desulfurized by the direct desulfurization apparatus 210 to be C heavy oil. Alternatively, it is pyrolyzed with a heavy oil pyrolysis device 209 to produce pyrolysis oil and petroleum coke. Petroleum coke becomes a product as coke. The pyrolysis oil is used as a raw material for the indirect desulfurization unit 207 together with the fraction by-produced in the direct desulfurization unit 210.

  According to the above oil refining process, mixed oil may be produced when the operation of each apparatus is switched, or a product with off-standard properties (off-spec) may be generated. In this case, these oils are collected in a slop tank as slop oil and are not shipped as a product.

  According to the results of the present inventors' research experiments, in the conventional method, in the slop oil, the light fraction at 360 ° C. or less has a heavy fraction of about 90% by volume or 360 ° C. It was found that the mass fraction was 10% by volume, and that most of the fraction was lighter than the light oil fraction.

  Therefore, in this example, the slop oil was roughly divided into a slop oil composed of a light component (light slop oil) and a slop oil composed of a heavy component (residual oil slop oil). The residual oil slop oil contains a heavier fraction containing vacuum gas oil, and the light slop oil contains a lighter fraction containing light oil.

  Furthermore, to explain, the residual oil slop oil which is a heavier fraction containing vacuum gas oil has a 10% distillation temperature in the range of 320 ° C. to 420 ° C., and a lighter fraction which is lighter than this containing gas oil. The slop oil preferably has a 90% distillation temperature in the range of 320 ° C to 420 ° C. In this example, the 10% distillation temperature of the residual oil slop oil was 360 ° C, and the 90% distillation temperature of the light slop oil was 360 ° C. However, the distillation temperature is not limited to this, and may be other temperatures as desired.

  Therefore, according to this embodiment, as the slop tank, the tank 300 dedicated to the residual oil slop oil and the tank 400 dedicated to the light slop oil are provided, and the light slop oil and the residual oil slop oil are separated into separate tanks, that is, The residual oil slop oil tank 300 and the light slop oil tank 400 were accepted respectively.

  If the residual oil slop oil tank 300 and the light slop oil tank 400 are not provided as in the present embodiment, they are collected in one slop tank without distinction between heavy and light as in the conventional method. When the structure is divided into a mass fraction and a light fraction, a fractionation (distillation) process that requires a heat source such as a stripper is required, and the same operation as that performed at an atmospheric distillation column is performed. This requires new fuel to operate this fractionation (distillation) process, resulting in loss of merit.

  As described above, the major feature of the present invention is that the residual oil slop oil and the light oil slop oil are received in the separate tanks 300 and 400, respectively. 101, sent to the atmospheric distillation tower 103 via the heating furnace 102 and processed, and the light slop oil is returned from the tank 400 as a raw material for the processing step disposed downstream of the atmospheric distillation tower 103 and processed. .

  In other words, according to the present invention, the residual slop oil generated in the residual oil treatment process for treating the residual oil is sent to the atmospheric distillation tower together with the crude oil to be processed, and the light slop generated in the light light treatment process for treating the fraction. The oil is returned and processed as a raw material for the residual oil treatment process or the light treatment process.

  Here, the light treatment step can be a hydrorefining, catalytic reforming, or catalytic cracking step for treating a fraction mainly composed of naphtha, gasoline, kerosene or light oil, and the residual oil. The treatment steps are (1) vacuum distillation, hydrorefining, thermal cracking or catalytic cracking of atmospheric residue, (2) hydrorefining, thermal cracking or catalytic cracking of vacuum residue, or (3) atmospheric residue. It can be a process of hydrorefining, hydrocracking, thermal cracking or catalytic cracking of distillate by vacuum distillation of oil.

  Further, the treatment step for returning the light slop oil may be a step for treating the heaviest fraction of the fractions, or a step for treating the residual oil. The treatment step for returning the waste water can be a step for treating the heaviest fraction of the fractions, or a step not containing the residual oil in the step for treating the residual oil.

  On the other hand, the step of treating the heaviest fraction can be a step of treating a light oil fraction, and the step of not treating the residual oil in the step of treating the residual oil is a normal pressure residual oil. It can be set as the process of processing the distillate by vacuum distillation.

  Further specific description will be given with reference to FIG.

  According to the present embodiment, the residual oil slop oil is a direct desulfurization apparatus 210, a vacuum distillation apparatus 206, an indirect desulfurization apparatus 207, a heavy oil pyrolysis apparatus 209, a flow, which are residual oil processing steps for processing the residual oil. It is slop oil from the catalytic cracking device 208. Further, the light slop oil is a naphtha hydrorefining device 202, kerosene hydrorefining device 204, light oil hydrorefining device 205, catalytic reforming device 203, etc., which are processing devices for processing a fraction distilled at atmospheric pressure. From the slop oil. The slop oil that does not contain residual oil from the heavy oil pyrolysis device 209 and the fluid catalytic cracking device 208 can be treated as a light slop oil.

  Therefore, the light slop oil is sent from the tank 400 as a raw material for the light oil hydrorefining device 205, which is a process for processing the heaviest fraction of the fractions. The light fraction slop oil is sent to the heavy oil indirect desulfurization unit 207 as a raw material.

  According to the present invention, as described above, the slop oil is treated by distinguishing the residual oil slop oil and the light slop oil according to the generation process, and the residual oil slop oil is returned to the atmospheric distillation column 103 in the same manner as in the prior art. By returning the slop oil to the processing apparatus downstream of the atmospheric distillation column 103, the flow rate of passing through the atmospheric distillation column 103 compared to the conventional case where all the slop oil is returned to the atmospheric distillation column 103. The fuel corresponding to the basic unit of the apparatus can be saved, and as a result, the energy can be saved and the carbon dioxide emission can be reduced. In addition, if gasoline or light oil is made sulfur-free or ultra-deep desulfurized, the above-mentioned merit is further increased from the viewpoint of the amount of off-spec products generated.

  In this example, if the ratio of light slop oil to all slop oil is 90% and the ratio of slop oil generated to the crude oil throughput is 2.5%, the amount of crude oil processed annually in Japan is 234. 964,381 KL and the fuel unit required for atmospheric distillation is 9.5 L / KL, which can reduce fuel consumption by 50,789 KL throughout Japan, Generation can be reduced.

It is a diagram which shows the outline | summary of one Example of the oil refinery process which implements the waste-oil processing method of this invention. It is a diagram which shows the outline | summary of an example of an oil refinery process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Crude oil tank 101 Crude oil desalination apparatus 102 Heating furnace 103 Atmospheric distillation tower 200 Processing apparatus 201 Gas recovery apparatus 202 Naphtha hydrorefining apparatus 203 Contact reformer 204 Kerosene hydrotreating apparatus 205 Light oil hydrotreating apparatus 206 Vacuum distillation apparatus 207 Indirect desulfurization device 208 Catalytic cracking device 209 Heavy oil thermal cracking device 210 Direct desulfurization device 300 Residual oil slop oil tank 400 Light slop oil tank

Claims (7)

Crude oil is separated into residual oil and at least one fraction in an atmospheric distillation tower, and then the fraction and the residual oil are further processed in a processing apparatus disposed downstream of the atmospheric distillation tower. In a waste oil treatment method for treating waste oil generated in an oil refining process for producing petroleum products,
Separate tanks for residual oil waste oil and tanks for light waste oil are installed separately.
The residual oil waste oil generated in the residual oil treatment process for treating the residual oil is received in a tank dedicated to the residual oil waste oil, and sent to the atmospheric distillation tower through the crude oil desalting apparatus and the heating furnace together with the crude oil, and processed.
A waste oil treatment method characterized in that light waste oil generated in a light treatment process for treating the fraction is received in a tank dedicated to light waste oil, and returned to the raw oil treatment process or the light treatment process as a raw material. Waste oil generated in the oil refining process, waste oil fraction produced from crude oil desalter, waste oil treatment method according to claim 1, characterized in that a混油or off-spec products generated when switching device.   The processing step of returning the light waste oil is a step of processing the heaviest fraction among the light processing steps of processing the fraction, or a step of processing residual oil. 2. Waste oil treatment method.   The method for treating waste oil according to claim 3, wherein the step of treating the residual oil is a step of treating a distillate obtained by distillation under reduced pressure of the atmospheric residual oil.   The waste oil treatment method according to claim 3 or 4, wherein the step of treating the heaviest fraction among the light treatment steps of treating the fraction is a step of treating a light oil fraction.   The waste oil treatment method according to any one of claims 1 to 5, wherein a 90% distillation temperature of the light waste oil is 320 to 420 ° C. The light treatment step is a hydrorefining, catalytic reforming or catalytic cracking step for treating a fraction mainly composed of naphtha, gasoline, kerosene or light oil,
The residual oil treatment step includes (1) vacuum distillation, hydrorefining, thermal decomposition or catalytic cracking of atmospheric residual oil, (2) hydrorefining, thermal cracking or catalytic cracking of vacuum residual oil, or (3) It is a process of hydrorefining, hydrocracking, thermal cracking or catalytic cracking of distillate by vacuum distillation of atmospheric residue.
The method for treating waste oil according to any one of claims 1 to 6, wherein:

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