阅读说明：本技术 一种原油或重油预处理组合工艺方法 (Crude oil or heavy oil pretreatment combined process method ) 是由 范景新 于海斌 郭春垒 臧甲忠 李犇 赵训志 赵闯 郭健 袁慎忠 郭子峰 聂枫 于 2021-09-20 设计创作，主要内容包括：本发明公开了一种原油或重油预处理组合工艺方法,该方法包括：原油或重油原料首先进入溶剂脱沥青单元进行溶剂脱沥青操作,所得脱油沥青产物物流进入装有吸附剂的分离塔实现沥青质的吸附分离,得到含解析剂的沥青质和再生的吸附剂,经解析得到沥青质,再生的吸附剂干燥后循环使用。本发明方法可降低原油或重油中沥青质、硫氮化合物及金属污染物含量,提高脱沥青油的收率和选择性。(The invention discloses a crude oil or heavy oil pretreatment combined process method, which comprises the following steps: crude oil or heavy oil raw materials firstly enter a solvent deasphalting unit for solvent deasphalting operation, the obtained deoiled asphalt product material flow enters a separation tower filled with an adsorbent to realize the adsorption and separation of asphaltene, the asphaltene containing the desorption agent and the regenerated adsorbent are obtained, the asphaltene is obtained through desorption, and the regenerated adsorbent is recycled after being dried. The method can reduce the contents of asphaltene, sulfur and nitrogen compounds and metal pollutants in the crude oil or the heavy oil, and improve the yield and the selectivity of the deasphalted oil.)

1. A combined process for pre-treating crude oil or heavy oil is used for removing asphaltene, sulfur and nitrogen compounds and metal pollutants in raw materials with high selectivity and simultaneously realizing high yield and selectivity of deasphalted oil, and is characterized by comprising the following steps:

(a) introducing raw oil and a non-aromatic solvent into a solvent deasphalting unit, and obtaining a product material flow containing deasphalted oil and a product material flow containing deasphalted asphalt under the condition of solvent deasphalting; the mass ratio of the non-aromatic solvent to the raw materials is 2: 1-15: 1;

(b) feeding the product material flow of the deasphalted oil in the step (a) into a separation tower to obtain deasphalted oil and a non-aromatic solvent;

(c) the deasphalted oil in the step (b) enters a catalytic cracking unit for directly preparing chemicals from crude oil, or is used as a catalytic cracking raw material, a hydrogenation raw material and for producing rubber filling oil;

(d) the product material flow containing the deoiled asphalt in the step (a) enters two towers which are connected in parallel and independently used adsorption towers, the asphaltene is further removed in the adsorption towers, and the obtained liquid phase product enters a separation tower together with the deasphalted oil in the step (b);

the adsorption towers are filled with adsorbents, when the amount of the asphaltenes adsorbed by the adsorbent of one adsorption tower reaches or approaches to the saturated adsorption amount, the adsorbent in the tower is considered to be deactivated, the deoiled asphalt product material flow is switched to the other adsorption tower, and the desorption agent is introduced into the tower containing the deactivated adsorbent to carry out the desorption of the asphaltenes, so that the asphaltenes containing the desorption agent and the regenerated adsorbent are obtained;

(e) separating the asphaltene containing the resolving agent in the step (d) to obtain the asphaltene.

(f) And (d) drying the regenerated adsorbent and then recycling the regenerated adsorbent.

2. The method of claim 1, wherein: the raw oil is one or mixture of heavy oil such as crude oil, atmospheric residue, vacuum residue, oil sand bitumen, etc.

3. The method of claim 1, wherein: the non-aromatic solvent is one of C3-C7 light hydrocarbon or the mixture of the light hydrocarbon in any proportion.

4. The method of claim 1, wherein: the mass ratio of the non-aromatic solvent to the raw materials is 2: 1-10: 1.

5. the method of claim 1, wherein: the adsorbent is high-purity mesoporous and macroporous silica gel or modified mesoporous and macroporous silica gel.

6. The method of claim 1, wherein: the resolving agent is low-carbon aromatic hydrocarbon or low-carbon alcohol.

7. The method of claim 6, wherein: the low-carbon aromatic hydrocarbon is one or a mixture of benzene, toluene, ethylbenzene and xylene, and the low-carbon alcohol is one or a mixture of methanol, ethanol and propanol.

8. The method of claim 1, wherein: the mass ratio of the adsorbent to the resolving agent is 3: 1-12: 1.

9. the method of claim 1, wherein: the condition of the analysis agent for asphaltene analysis is 20-80 ℃ and 0.1-1 MPa.

10. The method of claim 1, wherein: the non-aromatic solvent and the resolving agent are both recycled.

Technical Field

The invention relates to crude oil or heavy oil processing, belongs to the technical field of petrochemical industry, and particularly relates to a crude oil or heavy oil pretreatment combined process method.

Background

In the last 10 years, the oil refining industry in the world is continuously carrying out structure transformation and upgrading due to the influence of adverse factors such as fierce market competition of the finished oil, descending of processing profit margin, economic uncertainty and the like. Different from the market of finished oil, the olefin and the aromatic hydrocarbon are important basic chemical raw materials, have wide application and vigorous demand. Therefore, many large projects in construction and proposed construction around the world seek to improve the level of integration of refining.

The civil enterprises such as the perpetual petrochemical industry, the Zhejiang petrochemical industry, the rainbow petrochemical industry and the like in China are based on the principle of integrating refining into a factory and aim at maximizing the production of chemicals such as aromatic hydrocarbon, ethylene and the like, but the processing route of the civil enterprises takes large hydrocracking as a main processing means, so that the investment is huge, the processing cost is still higher, a certain amount of finished oil is still produced as a byproduct, and the competitiveness is to be further improved.

The technology for directly preparing chemicals from crude oil changes over the traditional processing concept, abandons the complex processing flow of a common refinery, directly introduces the crude oil into a special processing unit after simple treatment, produces chemicals such as olefin, aromatic hydrocarbon and the like to the maximum extent, and does not produce oil products such as gasoline, diesel and the like basically. Compared with the refining and chemical integration processing technology, the technology for directly preparing the chemicals from the crude oil has the advantages of shorter flow, lower energy consumption, higher yield of target products and the like, so that the competitiveness is stronger.

However, the existing technology for directly preparing chemicals from crude oil has limitations on raw materials, and is suitable for processing paraffin-base light crude oil, while heavy oil such as intermediate base crude oil, naphthenic base crude oil, vacuum residue oil, oil sand asphalt and the like has high asphaltene content and high impurity content, and if chemicals are directly produced by a catalytic cracking mode, the target product selectivity is poor, and the carbon deposition amount is increased.

The solvent deasphalting technology is mainly applied to preparing heavy lubricating oil from heavy oil in the early stage, and is gradually derived to be a very important pretreatment process for processing the heavy oil, so that most of non-ideal components such as asphaltene, heavy metals and the like in crude oil or other heavy raw materials can be removed, and deasphalted oil with better properties is obtained to be subjected to catalytic cracking, hydrocracking and other conventional process treatments.

CN200910012495.9 takes propane, butane or pentane as a solvent, and the volume ratio of the solvent is 6: 1-13: 1, firstly, carrying out solvent deasphalting treatment on the heavy oil raw material, and carrying out catalytic cracking or hydrocracking on the deasphalted oil. The deoiled asphalt and the hydrogen donor solvent including tetrahydronaphthalene or decahydronaphthalene are mixed for supercritical treatment to raise the utilization rate of inferior heavy oil.

CN201910109514.3 crude oil is fed into a solvent deasphalting zone along with an effective amount of solvent to produce a deasphalted and demetalized oil stream, which is then subjected to hydrogenation and steam thermal cracking to produce olefins and lower aromatics.

CN01805006.9 uses C₃、C₄、C₅The alkane, natural gas concentrate or their mixture is used as solvent to make solvent deasphalting of crude oil or crude oil fraction, and the asphalt product is fed into slurry hydrogenation treatment equipment so as to obtain the modified oil.

CN01141462.6 adopts light hydrocarbon (pentane or pentane fraction) with higher carbon atom number as solvent, the solvent is mixed with residual oil according to a certain proportion, and the mixture enters a solvent deasphalting tower to be separated to obtain deasphalted oil phase and asphalt phase, so as to obtain deasphalted oil with higher yield.

Thus, the existing solvent deasphalting technology still has the defects. When a lighter solvent such as propane is used, a higher deasphalted oil selectivity can be obtained, but the deasphalted oil yield is lower, while when a heavier solvent such as heptane is used, a higher deasphalted oil yield can be obtained, but the selectivity of the deasphalted oil is affected, and when a mixed solvent is used, part of the deasphalted oil yield and the selectivity need to be sacrificed, so that high deasphalted oil yield and selectivity cannot be simultaneously realized. When the solvent deasphalting technology is applied to the raw material pretreatment of crude oil chemicals, the problem that the yield and the selectivity of high-quality raw materials cannot be simultaneously considered is inevitably caused.

Disclosure of Invention

The invention mainly aims to provide a combined process method for pretreating crude oil or heavy oil aiming at the defects of the prior art, improve the quality of the crude oil, reduce the contents of asphaltene, sulfur and nitrogen compounds and metal pollutants in the crude oil, provide high-quality raw materials for a catalytic cracking unit for preparing chemicals from the crude oil, and maximize the yield and selectivity of the high-quality raw materials.

In order to achieve the above objects, the present invention provides a combined process for pre-treating crude oil or heavy oil, which is used for removing asphaltenes, sulfur and nitrogen compounds and metal pollutants in raw materials with high selectivity, simultaneously realizing high yield and selectivity of deasphalted oil, and providing high-quality raw materials for a cracking device for chemical products made from crude oil, and the process comprises:

(a) introducing raw oil and a non-aromatic solvent into a solvent deasphalting unit, and obtaining a product material flow containing deasphalted oil and a product material flow containing deasphalted asphalt under the condition of solvent deasphalting;

(b) feeding the product material flow of the deasphalted oil in the step (a) into a separation tower to obtain deasphalted oil and a non-aromatic solvent;

(c) the deasphalted oil in the step (b) enters a catalytic cracking unit for directly preparing chemicals from crude oil, or is used as a catalytic cracking raw material, a hydrogenation raw material, production rubber filling oil and the like;

(d) feeding the product material flow containing the deoiled asphalt in the step (a) into an adsorption tower, further removing asphaltene in the adsorption tower, and feeding the obtained liquid phase product into a separation tower together with the deasphalted oil in the step (b);

wherein the adsorption tower is formed by connecting two towers in parallel and independently using; loading adsorbents into the adsorption towers, when the amount of the asphaltenes adsorbed by the adsorbent in one adsorption tower reaches or approaches to the saturated adsorption amount of the adsorbents, considering that the adsorbent in the tower is deactivated, switching the deoiled asphalt product flow to the other adsorption tower, and introducing a resolving agent into the tower containing the deactivated adsorbent to perform the resolution of the asphaltenes to obtain the asphaltenes containing the resolving agent and the regenerated adsorbent;

(e) separating the asphaltene containing the resolving agent in the step (d) to obtain the asphaltene which can be used for road asphalt or gasification or coking or fuel;

(f) the regenerated adsorbent in the step (d) can be recycled after being dried.

In the pretreatment combined process method, the raw oil is preferably one of heavy oil such as crude oil, atmospheric residue, vacuum residue, oil sand bitumen and the like or a mixture of the heavy oil and the atmospheric residue, the vacuum residue and the oil sand bitumen.

In the pretreatment combined process method, the preferable non-aromatic solvent is one of C3-C7 light hydrocarbons or a mixture of the light hydrocarbons in any proportion.

In the pretreatment combined process method, the preferable mass ratio of the non-aromatic solvent to the raw materials is 2: 1-15: 1.

in the pretreatment combined process method, the solid adsorbent is preferably high-purity mesoporous and macroporous silica gel or modified mesoporous and macroporous silica gel.

In the pretreatment combined process method, the desorbent is preferably one or a mixture of low-carbon aromatic hydrocarbons such as benzene, toluene, ethylbenzene, xylene and the like, or one or a mixture of low-carbon alcohols such as methanol, ethanol, propanol and the like.

In the pretreatment combined process method, the mass ratio of the bulk adsorbent to the resolving agent is preferably 3: 1-12: 1.

in the pretreatment combined process method, the conditions for carrying out asphaltene analysis on the low-carbon aromatic hydrocarbon solvent are preferably 20-80 ℃ and 0.1-1 MPa;

in the pretreatment combined process method, the non-aromatic solvent and the low-carbon aromatic solvent resolving agent can be preferably recycled.

Compared with the prior art, the method has the beneficial effects that: the invention can reduce the contents of asphaltene, sulfur and nitrogen compounds and metal pollutants in crude oil or heavy oil, provides a high-quality raw material for a catalytic cracking unit for preparing chemicals from crude oil, avoids the influence of the asphaltene in the crude oil on a catalytic cracking catalyst for directly preparing the chemicals from the crude oil to the greatest extent, and maximizes the yield and selectivity of the high-quality raw material.

Drawings

FIG. 1 is a schematic diagram of the combined system and method for crude oil or heavy oil pretreatment of the present invention.

Description of the reference numerals

1 is raw oil, 2 is a non-aromatic solvent, 3 is a solvent deasphalting unit, 4 is a product stream containing deasphalted oil, 5 is a product stream containing deasphalted asphalt, 6 is a separation tower, 7 is a non-aromatic solvent, 8 is deasphalted oil, 9 is a first adsorption tower, 10 is a second adsorption tower, 11 is a resolving agent, and 12 is asphaltene containing the resolving agent.

Detailed Description

The following examples are intended to illustrate the practice and advantageous effects of the present invention, but are not to be construed as limiting the scope of the present invention.

Comparative example 1: solvent deasphalting of the raw materials only

The raw oil shown in Table 1 was used for solvent deasphalting under the following conditions: the temperature is 140 ℃, the pressure is 4MPa, the solvent is n-pentane, the weight ratio of the solvent is 6, and the properties of the solvent deasphalting product are shown in Table 2.

Example 1

By adopting the pretreatment combined process method, raw oil and a non-aromatic solvent are introduced into a solvent deasphalting unit, and solvent deasphalting is carried out under the operation conditions shown in the comparative example 1; and introducing the product material flow containing the deoiled asphalt obtained by the solvent deasphalting unit into one adsorption tower to remove the asphaltene, after the adsorbent is saturated, using the resolving agent to resolve the asphaltene, and simultaneously introducing the product material flow containing the deoiled asphalt obtained by the solvent deasphalting unit into the other adsorption tower to perform adsorption.

The mass ratio of the non-aromatic solvent to the raw oil is 4: 1, adopting a modified mesoporous silica gel solid adsorbent, wherein an analytic agent is a low-carbon aromatic solvent, specifically toluene, and the mass ratio of the solid adsorbent to the low-carbon aromatic is 4: 1, the condition for carrying out asphaltene analysis by using the low-carbon aromatic hydrocarbon solvent is 50 ℃ and 0.2 MPa.

Example 2

By adopting the pretreatment combined process method, raw oil and a non-aromatic solvent are introduced into a solvent deasphalting unit, and solvent deasphalting is carried out under the operation conditions shown in the comparative example 1; and introducing the product material flow containing the deoiled asphalt obtained by the solvent deasphalting unit into one adsorption tower to remove the asphaltene, after the adsorbent is saturated, using the resolving agent to resolve the asphaltene, and simultaneously introducing the product material flow containing the deoiled asphalt obtained by the solvent deasphalting unit into the other adsorption tower to perform adsorption.

The mass ratio of the non-aromatic solvent to the raw materials is 7: 1, adopting a modified mesoporous silica gel solid adsorbent, wherein an analytic agent is an alcohol solvent, specifically ethanol, and the mass ratio of the solid adsorbent to the analytic agent is 4: the conditions for asphaltene desorption by the desorbing agent were 50 ℃ and 0.2 MPa.

Example 3

By adopting the pretreatment combined process method, raw oil and a non-aromatic solvent are introduced into a solvent deasphalting unit, and solvent deasphalting is carried out under the operation conditions shown in the comparative example 1; and introducing the product material flow containing the deoiled asphalt obtained by the solvent deasphalting unit into one adsorption tower to remove the asphaltene, using a low-carbon aromatic solvent to analyze the asphaltene after the adsorbent is saturated, and simultaneously introducing the product material flow containing the deoiled asphalt obtained by the solvent deasphalting unit into the other adsorption tower to adsorb.

The mass ratio of the non-aromatic solvent to the raw materials is 7: 1, adopting a modified mesoporous silica gel solid adsorbent, taking benzene as a low-carbon aromatic solvent, wherein the mass ratio of the solid adsorbent to the low-carbon aromatic is 4: 1, the condition for carrying out asphaltene analysis by using the low-carbon aromatic hydrocarbon solvent is 60 ℃ and 0.2 MPa.

TABLE 1 oil feedstock Properties

Item	Unit of	Crude oil 1
			Sulfur content	wt％	2.0
Nitrogen content	wt％	0.59
			Carbon Residue (CCR)	wt％	22.1
Ni+V	μg/g	85
			Glue	wt％	26.7
Asphaltenes	wt％	6.8

TABLE 2 Properties of deasphalted oils after pretreatment of the oils

Item	Unit of	Comparative example 1	Example 1	Example 2	Example 3
						Deasphalted oil yield	wt％	74.6	85.5	87.1	87.0
Carbon Residue (CCR)	wt％	6.7	4.3	4.7	4.7
						Asphaltenes	wt％	2.10	0.07	0.80	0.82
Sulfur content	wt％	0.86	0.91	0.94	0.95
						Nitrogen content	wt％	0.28	0.30	0.32	0.32
Ni+V	μg/g	24.5	24.0	24.3	24.4
						Deasphalted oil selectivity	wt％	97.90	99.93	99.20	99.18

Deasphalted oil selectivity 100% -asphaltene content in deasphalted oil

By adopting the raw material pretreatment method provided by the invention, the solid adsorbent is introduced, so that the asphaltene in the product material flow containing the deoiled asphalt obtained by the solvent deasphalting unit is further adsorbed on the adsorbent, and then the deasphalted oil and the non-aromatic solvent are recovered, thereby more effectively improving the yield and the selectivity of the deasphalted oil. The above embodiments are only for illustrating the technical idea and features of the present invention, and the purpose of the embodiments is to enable people to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the main technical scheme of the invention are covered in the protection scope of the invention.