JPH0657829B2 - Method for removing solids from heavy oil - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for removing solids in heavy oil such as atmospheric distillation residual oil and vacuum distillation residual oil using a high gradient magnetic separation device. .

[Prior Art] Heavy oil contains heavy metals such as iron, nickel, and vanadium, and solid substances mixed in by corrosion of tanks, pipes, and other devices. When these heavy oils or solids due to corrosion are treated by, for example, fluid catalytic cracking, hydrodesulfurization, or hydrocracking, the heavy metals adhere to or deposit on the catalyst, degrading the activity of the catalyst. Alternatively, in the fixed bed reaction tower, the space between the catalyst particles is closed to increase the differential pressure in the catalyst bed.

Therefore, conventionally, the heavy oil is passed using a mesh filter having a plurality of filter elements to capture and remove the solid matter in the heavy oil, and with the increase of the differential pressure of the filter element, the The method of replacing and backwashing the element was adopted.

[Problems to be Solved by the Invention] However, in the method using the mesh filter, most of the particle diameters of the solids in the heavy oil are as small as 10 μm or less, and the heavy oil contains asphaltene content. Therefore, if the opening of the filter is made large, the solid matter is not sufficiently captured, and if the opening is made small, blockage occurs, the backwashing frequency increases, and the removal efficiency deteriorates. Had a problem.

By the way, in recent years, a high gradient magnetic separation method has been proposed as a method for removing magnetic particles (see, for example, JP-A-59-59).
(See Japanese Patent No. 115716). This method fills the magnetic fine wire in the magnetic field space generated by the electromagnet, and effectively utilizes the high gradient magnetic field generated around the magnetic fine wire as a filter by magnetizing the fine wire. Has been done.

The present inventors have studied the application of the high gradient magnetic separation method to the removal of solids in the heavy oil, and as it is, the magnetic susceptibility of the solids is low due to asphaltene etc. Although the efficiency is low, it was found that the removal efficiency is remarkably enhanced by using the aromatic base material.

The present invention has been made based on the above findings, and an object of the present invention is to provide a method for efficiently removing solid matter in heavy oil, and even removing particles of several μ or less.

[Means for Solving the Problems] As a means for solving the above problems, the present invention removes solids by mixing a heavy oil with an aromatic base material and using a high gradient magnetic separator. In particular, a method of removing solids in heavy oil, which comprises mixing the aromatic base material to 5% by volume or more, is particularly preferable.

The heavy oil of the present invention includes atmospheric distillation residual oil obtained by atmospheric distillation of crude oil, or vacuum distillation residual oil obtained by vacuum distillation of this crude oil, and further deasphalted residual oil thereof. etc,
Oils with a relatively high asphaltene content are suitable. Needless to say, these heavy oils may be used alone or as a mixture of plural oils.

Further, as the aromatic base material referred to in the present invention, benzene,
Aromatic solvents such as toluene and xylene, light fractions produced by catalytic cracking, thermal cracking or coking of petroleum fractions or residual oil, or heavy fractions, or by-products during solvent purification of lubricating oils. A so-called extract or the like that grows is preferably used. In particular, light cycle oil (light cycle oil), which is a by-product of fluid catalytic cracking of a light oil fraction, ethylene tar, which is a by-product of ethylene production, and coker light gasoline fraction, which is a by-product of heavy oil coking. And the like are preferably used.

The amount of these aromatic base materials to be mixed cannot be unconditionally determined depending on the content of asphaltene in the heavy oil or the type or content of the aromatic components contained in the aromatic base material, It is sufficient to mix at least 5% by weight.
If the mixing amount is 5% by weight or less, the effect of increasing the removal efficiency of solids in heavy oil cannot be expected so much. If the mixing amount of the aromatic base material is large, the processing amount of the heavy oil will be reduced. Therefore, economically, as small as possible,
It is preferable that the volume is 50 or less.

The high-gradient magnetic separation device is configured such that a thin magnetic pole wire is filled in the filter vessel through pole pieces (magnetic pole irons) at upper and lower portions so as to be perpendicular to the magnetic field lines, and an electromagnet that generates magnetic field lines is provided around the vessel. A commercially available product having a structure provided with can be used as it is.

When the temperature of the oil is high in the case of processing with the high gradient magnetic separation device, the higher the removal rate is, the more preferable. However, if the temperature is too high, the magnetic susceptibility of the particles decreases. Therefore, it is preferable to perform the treatment at a temperature of room temperature to 260 ° C. The magnetic field is 0.5 to
If it is 20 KOe, solid matter can be sufficiently captured. Furthermore, the filter in the device is 10-50.
A wire mesh fine pole wire having a thickness of 0.02 to 3 mm and a thickness of 50 to 400 mm formed in a layer shape with a mesh of 0 mesh is preferably used.

[Embodiment] One embodiment of an application example of the present invention will be described with reference to the drawings.

An aromatic base material is mixed with the heavy oil to be treated, and introduced into the line mixer 1 in order to sufficiently perform the mixing.
If the line mixer 1 is a nozzle mixer, an orifice mixer, an injector mixer, or the like that can be stirred at high speed, the two liquids can be efficiently mixed, and the solid removal efficiency is improved.

The oil mixed in the line mixer 1 is supplied to either one of the plurality of high gradient magnetic separation devices 2 provided. Here, the solid matter in the heavy oil is trapped in the mesh layer from the magnetic fine wire in the separation device 2. The heavy oil from which the solid matter has been captured and removed is supplied to the raw material container 3. When the trapping effect of the high gradient magnetic separation device 2 decreases, the other high gradient magnetic separation device 2 is switched to and regenerated. In the case of regeneration, the electromagnetic force of the high gradient magnetic separation device 2 is cut off, and the backwashing liquid and gas are made to flow from the containers 4 and 5 at the same time and in the opposite direction to that at the time of processing. By using the liquid and the gas at the same time, the solid matter trapped in the mesh layer can be efficiently removed by the vibration caused by bubbling.
The backwash liquid and the gas are separated in the gas-liquid separation container 6. The solid material is concentrated in the liquid layer of the separator 6, and the solid material is separated by sedimentation, centrifugation or the like. Incidentally, as the backwashing liquid in this regeneration, it is preferable to use the same heavy oil as the object to be treated, because it is not necessary to replace the retained oil in the apparatus and to wash the inside of the container. Furthermore, in consideration of the fact that mineral oil is flammable, it is necessary to use an inert gas such as nitrogen gas as the backwash gas, but in particular, off gas emitted from petroleum refining plants, petrochemical plants, etc. It is economically preferable to use.

As described above, the solid content in the heavy oil can be continuously removed by alternately capturing and regenerating the high gradient magnetic separation devices 2.

Experimental example Heavy oil containing 55 ppm by weight of solids (specific gravity 15/4 ° C, 0.95
8, the viscosity of 50 ° C., 242 cst) was mixed with the aromatic base material as shown in the table, and the solid matter was captured and removed by the high gradient magnetic separation device. The high-gradient magnetic separation device has a filter part having an opening of 100 μ and an overlength of 150 mm, and was processed under the conditions of an overspeed of 42 m / Hr, a magnetic field strength of 3.2 KOe, and a processing liquid temperature of 70 ° C. The results are shown in the following table together with a comparative experiment example in which the aromatic base material was not mixed.

[Effects of the Invention] In the present invention, the heavy oil is mixed with the aromatic base material so as to remove the solid content by the high gradient magnetic separator, so that the fine solid matter in the heavy oil can be efficiently removed. It has a special effect.

[Brief description of drawings]

The figure shows a flow for explaining an embodiment to which the present invention is applied. In the figure, 2 is a high gradient magnetic separation device.

Front page continuation (72) Inventor Takami Akada 2-1-1, Shiododori, Kurashiki-shi, Okayama Japan Mining Co., Ltd. Mizushima Refinery (72) Inventor Akio Saito 2-1-2, Shiododori, Kurashiki-shi, Okayama Japan Mining Co., Ltd. Mizushima Inside the refinery (72) Inventor Hiroki Koyama 2-1, Shiododori, Kurashiki-shi, Okayama Japan Mining Co., Ltd. Mizushima Refinery

Claims (2)

[Claims] 1. A method for removing solids in heavy oil, which comprises mixing an aromatic base material with heavy oil and removing solids by a high gradient magnetic separation device. 2. The mixing of the aromatic base material is at least 5
The method for removing solids from heavy oil according to claim 1, characterized in that the content is% by volume.