阅读说明：本技术 渣油加氢原料预处理方法及其装置以及渣油加氢工艺 (Residual oil hydrogenation raw material pretreatment method and device thereof and residual oil hydrogenation process ) 是由 陈强 李小婷 盛维武 蔡连波 赵晓青 刘茂增 陈险峰 魏嘉 于 2020-05-22 设计创作，主要内容包括：本发明公开了渣油加氢原料预处理方法及其装置以及渣油加氢工艺,涉及石油炼制技术领域。渣油加氢原料预处理方法包括将原料油通过具有楔形过滤空间的过滤器,过滤器上安装有能够超声作用于楔形过滤空间的超声波发生器,超声波发生器的频率为15-25kHz,过滤器的操作压力为0.5MPa以上。使原料油经过过滤器处理之后的粘度显著降低,这很可能是由于渣油在过滤器的楔形过滤空间中同时产生水利空化和超声空化,降低渣油的残炭含量和粘度。本发明中的预处理方法和对应的预处理装置可以在不改变原有工艺条件下实现水利空化和超声空化,工业应用前景较好,该渣油加氢工艺采用上述预处理方法进行原料的预处理,能够显著提升轻质油收率。(The invention discloses a residual oil hydrogenation raw material pretreatment method, a residual oil hydrogenation raw material pretreatment device and a residual oil hydrogenation process, and relates to the technical field of petroleum refining. The residual oil hydrogenation raw material pretreatment method comprises the steps of enabling raw oil to pass through a filter with a wedge-shaped filtering space, installing an ultrasonic generator capable of ultrasonically acting on the wedge-shaped filtering space on the filter, enabling the frequency of the ultrasonic generator to be 15-25kHz, and enabling the operating pressure of the filter to be more than 0.5 MPa. The viscosity of the raw oil after being processed by the filter is obviously reduced, which is probably because the residual oil simultaneously generates water conservancy cavitation and ultrasonic cavitation in the wedge-shaped filtering space of the filter, and the carbon residue content and the viscosity of the residual oil are reduced. The pretreatment method and the corresponding pretreatment device can realize water conservancy cavitation and ultrasonic cavitation without changing the original process conditions, have good industrial application prospect, and can remarkably improve the yield of the light oil by adopting the pretreatment method to carry out pretreatment on the raw material in the residual oil hydrogenation process.)

1. The pretreatment method of the residual oil hydrogenation raw material is characterized by comprising the step of enabling the raw material oil to pass through a filter with a wedge-shaped filtering space, wherein an ultrasonic generator capable of ultrasonically acting on the wedge-shaped filtering space is installed on the filter, the frequency of the ultrasonic generator is 15-25kHz, and the operating pressure of the filter is more than 0.5 MPa.

2. The residue hydrogenation feedstock pretreatment method of claim 1, wherein the filter is a backwash filter, and the ultrasonic generator is internal or external;

preferably, the ultrasonic generator is installed in the inner cavity of the backwashing filter.

3. The residue hydrogenation feedstock pretreatment method of claim 2, wherein the back-flushing filter is operated at a temperature of 250 ℃ and 300 ℃ and at a pressure of 0.5 to 1.5 MPa;

preferably, the operating temperature of the backwashing filter is 270 ℃ and 290 ℃, and the pressure is 0.8-1.2 MPa.

4. A residue hydroprocessing feedstock pretreatment process as recited in claim 1, characterized in that the ultrasonic generator has a frequency of from 18 to 22 kHz;

preferably, the maximum amplitude of the ultrasonic generator is 10-20 μm.

5. The resid hydroprocessmg process of claim 1, wherein the feed oil flow rate is less than or equal to 5 mm/s; preferably, the flow rate of the raw oil is 0.1-5 mm/s.

6. The resid hydroprocessmg process of claim 5, wherein said feedstock is stored in a first buffer tank prior to being passed to said filter, the storage in said first buffer tank being monitored by a feedback regulation system, and the booster pump pressure and ultrasonic generator frequency between said first buffer tank and said filter being controlled.

7. The resid hydroprocessmg process of claim 6, wherein the output from said filter is passed to a second surge tank and a return line is provided between said first surge tank and said second surge tank.

8. The resid hydroprocessmg process of claim 7, wherein the mass of reflux from said second buffer tank to said first buffer tank is less than or equal to 10% of the total inventory of said second buffer tank.

9. A pretreatment apparatus for a residue hydrogenation feedstock for carrying out the pretreatment method according to any one of claims 1 to 8, characterized by comprising a filter having a wedge-shaped filtration space, the filter being provided with an ultrasonic generator capable of ultrasonically acting on the wedge-shaped filtration space;

preferably, the ultrasonic wave filter further comprises a first buffer tank, a booster pump and a feedback adjusting system for detecting the storage amount in the first buffer tank, wherein the booster pump is respectively connected with the discharge hole of the first buffer tank and the feed hole of the filter, and the booster pump and the ultrasonic generator are both in communication connection with the feedback adjusting system;

preferably, still include second buffer tank and return line, return line's one end with the discharge gate of second buffer tank links to each other, the other end with the feed inlet intercommunication of first buffer tank.

10. A residual oil hydrogenation process, characterized in that it employs the residual oil hydrogenation feedstock pretreatment method according to any one of claims 1 to 9 for pretreatment of a raw oil.

Technical Field

The invention relates to the technical field of petroleum refining, in particular to a method and a device for pretreating a residual oil hydrogenation raw material and a residual oil hydrogenation process.

Background

With the reduction of world petroleum reserves, the aggravation of the trend of crude oil heaviness and deterioration, the increasingly strict requirements of environmental protection laws and regulations, the increase of light petroleum product demand and the continuous upgrading and updating of product quality, how to utilize petroleum resources cleanly and efficiently becomes an important problem facing the world. The residual oil is the heaviest component in the crude oil, has large average relative molecular mass, high boiling point and large viscosity and polarity, concentrates most of sulfur-containing, nitrogen-containing and oxygen-containing compounds and colloids, and all asphaltenes and heavy metals in the crude oil, and is the key and difficult point of oil product processing. The residual oil hydrogenation technology can obviously improve the properties of the residual oil and is an important means for efficiently utilizing heavy petroleum resources.

At present, the research on residual oil hydrogenation mainly focuses on the forms of a reactor (a fixed bed, a slurry bed, a boiling bed and the like) and high-efficiency catalysts, and along with the research on the process and the catalysts, the research on related engineering technologies such as components in the reactor, large-scale equipment, system energy conservation, addition of auxiliaries, micro-interface strengthening and the like also focuses on the research on the residual oil hydrogenation. A large number of basic researches by domestic and foreign research institutions discover that the desulfurization reaction rate in the residual oil hydrogenation process is mainly related to the asphaltene content in the raw oil, and the lower the asphaltene content is, the higher the hydrodesulfurization reaction rate is. In addition, the viscosity of the residual oil raw material also has an important influence on the activity of the catalyst in the residual oil hydrogenation process, because the residual oil hydrotreating process is a process controlled by diffusion, the higher the viscosity of the raw oil is, the higher the flow of raw oil molecules in a bed layer and the mass transfer diffusion resistance inside catalyst particles are, the slower the hydrogenation reaction speed is, the lower the impurity removal rate at the same volume space velocity is, and the lower the conversion rate in the hydrogenation process is. Therefore, if the viscosity of the feedstock oil is too high, the hydrotreating reaction is not favored.

However, most of the prior viscosity reduction methods for raw oil are still in the laboratory research stage, or the original process flow is greatly changed, so that the method is difficult to be applied industrially, such as adding cavitation equipment such as a venturi tube or generating large pressure drop.

Disclosure of Invention

The invention aims to provide a residual oil hydrogenation raw material pretreatment method which has little change to the original treatment process, is convenient for industrial application, and can significantly reduce the viscosity of residual oil, improve the yield of light oil after hydrogenation reaction and reduce the yield of coke.

Another object of the present invention is to provide a residual oil hydrogenation feedstock pretreatment apparatus, which is convenient for industrial application and can significantly reduce the viscosity of residual oil.

The third purpose of the invention is to provide a residual oil hydrogenation process, which has high yield of light oil and low yield of coke.

The technical problem to be solved by the invention is realized by adopting the following technical scheme.

The invention provides a residual oil hydrogenation raw material pretreatment method, which comprises the steps of enabling raw oil to pass through a filter with a wedge-shaped filtering space, installing an ultrasonic generator capable of ultrasonically acting on the wedge-shaped filtering space on the filter, enabling the frequency of the ultrasonic generator to be 15-25kHz, and enabling the operating pressure of the filter to be more than 0.5 MPa.

The invention also provides a residual oil hydrogenation raw material pretreatment device which comprises a filter with a wedge-shaped filtering space, wherein an ultrasonic generator capable of ultrasonically acting on the wedge-shaped filtering space is arranged on the filter.

The invention also provides a residual oil hydrogenation process, which adopts the residual oil hydrogenation raw material pretreatment method to carry out pretreatment of raw oil.

The embodiment of the invention provides a pretreatment method of a residual oil hydrogenation raw material, which has the beneficial effects that: the viscosity of the raw oil after being processed by the filter is obviously reduced by installing the ultrasonic generator on the filter in the original pretreatment process and controlling the operating pressure of the filter, the frequency of the ultrasonic generator and other conditions, which probably results from the fact that the residual oil simultaneously generates water conservancy cavitation and ultrasonic cavitation in the wedge-shaped filtering space of the filter, the average relative molecular mass of the residual oil is obviously reduced, and the residual carbon content and the viscosity of the residual oil are reduced.

The embodiment of the invention provides a residual oil hydrogenation raw material pretreatment device which is convenient for industrial application and can obviously reduce the viscosity of residual oil through the dual functions of a filter and an ultrasonic generator.

Particularly, the inventor creatively discovers that after the ultrasonic generator is introduced, the ultrasonic cavitation is caused, and simultaneously, the hydrodynamic cavitation can be generated in the pressure drop range which cannot generate hydrodynamic cavitation originally, so that the coupling effect of the two cavitation is realized. The pretreatment method can realize two kinds of cavitation within the pressure drop range of the original pretreatment process, has low energy consumption and can easily realize industrial application.

The embodiment of the invention also provides a residual oil hydrogenation process, wherein the residual oil hydrogenation raw material pretreatment method is adopted for pretreatment of raw oil, so that the yield of light oil after hydrogenation reaction is greatly improved, and the yield of coke is reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic diagram of residue hydrogenation;

FIG. 2 is a schematic diagram of a residue hydrogenation feed pretreatment process provided by an embodiment of the present invention;

FIG. 3 is a schematic diagram of a residue hydroprocessing feedstock pretreatment process provided by another embodiment of the present invention;

FIG. 4 is a gas phase profile without sonication;

FIG. 5 is a gas phase distribution diagram under the action of ultrasound;

FIG. 6 is a gas phase distribution diagram in the filter tube.

Icon: 1-a first buffer tank; 2, a booster pump; 3-backwashing the filter; 4-a second buffer tank, 5-a hydrogenation feed pump; 6-ultrasonic generator; 7-wedge-shaped wire mesh filter tubes; 8-a feedback regulation system; 9-a return line; 10-reflux pump.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The method for pretreating a residue hydrogenation raw material, the device thereof and the residue hydrogenation process provided by the embodiment of the invention are specifically described below.

Referring to fig. 1, the residual oil is a colloid system which takes asphaltene and colloid as dispersed phases and takes saturated components and aromatic components as dispersion media. In the system, the asphaltene molecules with the highest aromaticity are gathered into a gum core, the gum with slightly lower aromaticity is attached to the outer side of the gum core, and the saturated component and the aromatic component are arranged on the outermost sides. The colloid and the asphaltene have an inhibiting effect on the dissolution of hydrogen in residual oil, so that coking and catalyst deactivation are caused, and the hydrogen consumption in the hydrogenation process can be increased due to the excessively high content of the asphaltene. During hydrogenation reaction, hydrogen is dissolved in residual oil in a gap filling mode, and due to the stable existence of a micelle system, the hydrogen cannot enter the inside of the micelle.

The embodiment of the invention provides a pretreatment method of a residual oil hydrogenation raw material, which comprises the step of enabling raw oil to pass through a filter which generates a pressure drop of more than 0.5MPa and is provided with a wedge-shaped filtering space, wherein an ultrasonic generator is arranged on the filter, and the frequency of the ultrasonic generator is 15-25 kHz.

The inventor finds that the average relative molecular mass of the residual oil is reduced after the raw oil passes through the filter, the carbon residue and the viscosity are obviously reduced, and the yield of the light oil is greatly improved and the yield of the coke is reduced after the residual oil is further subjected to the subsequent fixed bed or boiling bed hydrogenation reaction. The reason for this phenomenon is probably that the coupling action of two cavitation mechanisms is formed by the wedge-shaped microfiltration space and the ultrasonic wave when the residual oil passes through the wedge-shaped filtration space of the filter, so that the respective advantages are exerted and the defects of each other are overcome. The inventor also finds that residual oil molecules are changed microscopically after water conservancy cavitation and ultrasonic cavitation, the hydrogen dissolving amount of the residual oil is increased, and the probability of contact between hydrogen molecules and asphaltene molecules is increased, so that the residual oil hydrogenation effect can be improved.

Particularly, the pressure drop for generating the hydraulic cavitation generally needs 2-3MPa, while the pressure drop for generating the hydraulic cavitation by a filter in the pretreatment process of the common residual oil hydrogenation raw material can be about 1MPa, which is not enough for generating the hydraulic cavitation. The inventor creatively introduces the ultrasonic generator and can generate the hydraulic cavitation under the original pressure drop condition at the same time of generating the ultrasonic cavitation.

Specifically, the raw oil may include slag reduction, wax oil, deasphalted oil, and the like.

Further, the frequency of the ultrasonic generator is 18-22 kHz; preferably, the maximum amplitude of the sonotrode is 10-20 μm. The cavitation effect is ensured by further controlling the working parameters of the ultrasonic generator on the premise of smaller energy consumption. In particular, the ultrasonic generator is a conventional device, which may be of the type LYHCCS 01. The acoustic power is 4.73W/cm2 through numerical simulation, the oscillator power is 1.784W, and the cavitation can be realized.

In some embodiments, the pressure drop of the filter is 0.6-1MPa, and two kinds of cavitation can be realized by only adding the ultrasonic generator on the premise of not changing the original process conditions, so that the industrial application is facilitated.

Referring to fig. 2, the filter is a backwashing filter 3, and the ultrasonic generator 6 is built-in or external. On one hand, the residual oil backwashing filter 3 is not easy to block under the action of ultrasonic wave, and the backwashing frequency is greatly reduced; on the other hand, residual oil molecules can be changed microscopically through primary cavitation and secondary cavitation, the hydrogen dissolving amount of the residual oil is improved, the probability of contact of hydrogen molecules and asphaltene molecules is increased, and therefore the residual oil hydrogenation effect can be improved.

In some embodiments, the ultrasonic generator 6 is installed in the inner cavity of the backwashing filter 3, the abrasion to the wall surface of the filter can be reduced by adopting a built-in mode, a plurality of wedge-shaped wire mesh filter pipes 7 are arranged in the backwashing filter 3, and the backwashing filter 3 is an existing device and is a common device in residual oil pretreatment.

Furthermore, the pressure difference of the filter pipe on the back washing filter 3 is 0.4-0.6MPa, the operation temperature of the back washing filter 3 is 250-300 ℃, and the pressure is 0.5-1.5 MPa; preferably, the operating temperature of the backwashing filter 3 is 270 ℃ and 290 ℃, and the pressure is 0.8-1.2 MPa. The working condition of the filter is about the same as that of the original process, and the viscosity of the residual oil can be obviously reduced by matching with an ultrasonic generator in the range.

Further, the flow rate of the raw oil is less than or equal to 5 mm/s; preferably, the flow rate of the feedstock oil is 0.1 to 5 mm/s. Too high a flow rate of the raw oil results in poor cavitation effect and poor viscosity reduction effect.

For better control of the flow rate, the crude oil is stored in the first buffer tank 1 before being introduced into the backflushing filter 3, the storage volume in the first buffer tank 1 is detected by the feedback control system 8, and the pressure of the booster pump (i.e. the booster pump 2) between the first buffer tank 1 and the backflushing filter 3 and the frequency of the ultrasonic generator 6 are controlled. When the oil quantity in the first buffer tank 1 is detected to be less, the feed pressure can be ensured by the booster pump 2, but the flow can be properly reduced, the retention time of the residual oil in the back flush filter is prolonged, the intensity of the ultrasonic wave can be properly adjusted by the feedback adjusting system 8, and the energy consumption of the system is reduced while the cavitation effect is ensured.

Specifically, the material output from the backwashing filter 3 is introduced into a second buffer tank 4, and then enters a raw oil heat exchange system after passing through a hydrogenation feed pump 5.

In particular, the feedback regulation system 8 is a processor, which may be an integrated circuit chip, having signal processing capabilities. The Processor may be a general-purpose Processor, including a Central Processing Unit (CPU), a Network Processor (NP), and the like; but may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, discrete hardware component. A general purpose processor may be a microprocessor; the processor may also be any conventional processor or the like. In the present embodiment, the processor may be an STM32 series processor, such as an STM32F103C8T6, an STM32F103VET6, or the like.

In some preferred embodiments, referring to fig. 3, in order to further enhance the cavitation effect, the residence time of the residual oil in the backflushing filter 3 is properly adjusted, the material output from the backflushing filter 3 is introduced into the second buffer tank 4, and a return line 9 is arranged between the first buffer tank 1 and the second buffer tank 4 and is conveyed by a return pump 10. The mass of the liquid returned from the second buffer tank to the first buffer tank is preferably less than or equal to 10% of the total storage capacity of the second buffer tank.

Referring to fig. 1-2, the embodiment of the present invention further provides a residual oil hydrogenation feedstock pretreatment device for implementing the pretreatment method, which comprises a filter (i.e. a back-washing filter 3 in the figure) with a wedge-shaped filtering space, wherein an ultrasonic generator 6 capable of ultrasonically acting on the wedge-shaped filtering space is arranged on the filter. For the detailed working principle, please refer to the preprocessing method, which is not described herein in detail.

In some embodiments, the system further comprises a first buffer tank 1, a booster pump 2 and a feedback regulation system 8 for detecting the storage amount in the first buffer tank 1, wherein the booster pump 2 is respectively connected with the discharge port of the first buffer tank 1 and the feed port of the filter, and the booster pump 2 and the ultrasonic generator 6 are both in communication connection with the feedback regulation system 8.

In some embodiments, the device further comprises a second buffer tank 4 and a return pipeline 9, wherein one end of the return pipeline 9 is connected with the discharge hole of the second buffer tank 4, and the other end of the return pipeline is communicated with the feed hole of the first buffer tank 1.

The embodiment of the invention also provides a residual oil hydrogenation process, which adopts the residual oil hydrogenation raw material pretreatment method to carry out pretreatment of raw oil, and the pretreated residual oil enters a heat exchange system. The method of other parts of the residual oil hydrogenation process is the existing method, and redundant description is not provided herein.

It should be noted that the pretreatment method provided by the embodiment of the present invention can implement cavitation under low pressure drop, ensure that the operation period is prolonged by 3 to 6 months and the light oil yield is increased by 0.5 to 2%, and reduce the backwashing frequency of the backwashing filter by 50%, after the treated residual oil enters the hydrogenation reactor.

The features and properties of the present invention are described in further detail below with reference to examples.