阅读说明：本技术 一种用溶剂从油砂中提取道路沥青的系统及方法 (System and method for extracting road asphalt from oil sand by using solvent ) 是由 陈虹均 陈建树 吴泽雄 于 2018-06-01 设计创作，主要内容包括：本发明为一种用溶剂从油砂中提取道路沥青的系统及方法,通过交替连接的至少两级抽提装置及至少两级离心分离装置,且二级抽提、离心分离出的二级混合液返回一级抽提装置,形成逆流抽提、溶剂循环利用,每个过程生成的固液气的产物均利用起来,解决了利用天然沥青生产道路沥青的问题,还解决了含油砂砾的污染问题,既可以保障能量自身需求,又在高温下除掉了污染物,而且由于设备是在全密封的环境下运行的,对环境没有任何污染。(The invention relates to a system and a method for extracting road asphalt from oil sand by using a solvent, wherein at least two stages of extraction devices and at least two stages of centrifugal separation devices are alternately connected, secondary mixed liquid obtained by secondary extraction and centrifugal separation returns to the primary extraction device to form countercurrent extraction and solvent recycling, and solid-liquid-gas products generated in each process are all utilized, so that the problem of producing the road asphalt by using natural asphalt is solved, the pollution problem of oil-containing gravel is also solved, the energy requirement can be guaranteed, pollutants are removed at high temperature, and no pollution is caused to the environment because equipment operates in a fully sealed environment.)

1. A system for extracting road asphalt from oil sand by using a solvent is characterized by comprising a rotary drying device, at least two stages of extraction devices, at least two stages of centrifugal separation devices, a rotary burning device and a mixed liquid separation device, wherein the at least two stages of extraction devices are sequentially and alternately connected with the rotary drying device, the mixed liquid separation device is connected with a first-stage centrifugal separation device, and a liquid phase outlet of a final-stage centrifugal separation device is connected with an inlet of the first-stage extraction device in a return mode.

2. The system for extracting the road asphalt from the oil sand by using the solvent as claimed in claim 1, which is characterized by comprising a rotary drying device (11), and a primary extraction device (2), a primary centrifugal separation device (3), a secondary extraction device (5), a secondary centrifugal separation device (6) and a rotary incineration device (10) which are sequentially connected with the rotary drying device; the liquid outlet of the primary centrifugal separation device 3 is connected with a normal pressure separation device (12), the mixed liquid outlet of the normal pressure separation device (12) is connected with a decompression separation device (13), and the decompression separation device (13) comprises a fuel oil outlet and a road asphalt outlet; a solvent inlet of the secondary extraction device (5) is connected with a circulating solvent storage tank (9), and a solvent outlet of the normal-pressure separation device (12) is connected with an inlet or an inlet pipeline of the circulating solvent storage tank (9); and a liquid outlet of the secondary centrifugal separation device (6) is connected back to a solvent inlet of the primary extraction device (2).

3. The system for extracting the road asphalt from the oil sand by using the solvent as claimed in claim 1, wherein the flue gas outlet of the rotary incineration device (10) is connected with a rotary drying device (11), and the solid phase outlet is connected with a tailing heat exchange device (21).

4. A method for extracting road asphalt from oil sand by using a solvent is characterized by comprising the steps of crushing and screening an oil sand raw material (1), drying the oil sand raw material in a rotary drying device (11), enabling the dried oil sand to enter a primary extraction device (2), mixing the dried oil sand according to the volume ratio of the solvent to the oil sand being 1 ~ 3:1, enabling a solid-liquid mixture obtained by extraction to enter the primary centrifugal separation device 3 for primary centrifugal separation, enabling solid-phase gravel obtained by separation to enter a secondary extraction device (5), enabling primary mixed liquid obtained by separation to enter an atmospheric separation device (12), distilling the atmospheric separation device (12) at normal pressure to obtain the solvent and natural asphalt, recycling the solvent to a circulating solvent storage tank (9), enabling the natural asphalt to enter a reduced pressure separation device (13) for reduced pressure distillation to obtain fuel oil (15) and road asphalt (16), enabling the solid-phase gravel entering the secondary extraction device (5) to be mixed according to the volume ratio of the solvent to the solid-phase gravel being 1 ~ 3:1, enabling the solid-phase gravel entering the secondary extraction device (10) to enter a rotary centrifugal separation device (10), enabling the solid-phase gravel mixture obtained by extraction device to be burned at the temperature of the two-stage centrifugal separation device (25 ~ 120) and burning process.

5. The method for extracting road asphalt from oil sand by using solvent as claimed in claim 4, wherein the hot flue gas (181) generated after the incineration and decomposition of the oil-containing gravel in the rotary incineration device (10) is introduced into the rotary drying device (11) to participate in the drying process.

6. A method for extracting road asphalt from oil sand by using solvent according to claim 4, characterized in that the hot tailings (201) generated after the solid-phase oil-containing gravel (8) is incinerated and decomposed is passed to a tailings heat exchanger (21).

7. The method for extracting road bitumen from oil sands with solvents according to claim 4, wherein the drying time of the tailings is 30 to 60 minutes.

8. The process for extracting road bitumen from oil sands with solvents according to claim 4, wherein the mixing time in the reaction tank of the primary and secondary extraction device is 15 ~ 30 minutes.

9. The method for extracting road bitumen from oil sands using a solvent according to claim 4, wherein the solvent is one or a mixture of two or more hydrocarbons selected from naphtha, reformed gasoline, kerosene, diesel, crude oil, C ₉ aromatics, ethylene cracked light diesel, and fuel oil.

10. The process for the extraction of road bitumen from oil sands with solvent according to any of claims 4 to 9, characterized in that the oil sands have a natural bitumen extraction of 92 ~ 95% with a cyclic solvent loss of 0.5 ~ 2%.

Technical Field

The invention relates to a system and a method for extracting road asphalt from oil sand by using a solvent, belonging to the technical field of oil sand separation.

Background

Oil sand is a sand or sandstone containing natural bitumen or tar, is an unconventional sandy deposit containing crude oil, and is a preferred material for refining petroleum products and constructing asphalt pavements. Under the condition of increasing international petroleum demand, the heavy oil bitumen resource enriched in oil sand is developed, and the method has wide market prospect and economic benefit.

The global oil sand resource has huge potential, the recoverable resource amount of the global oil sand resource is equivalent to the residual recoverable resource amount of conventional petroleum, and oil sand resources are reserved in more than 70 countries in the world, but only 12% of the oil sand resources can be economically exploited and utilized by the current technology, and if the oil sand resources are completely exploited and utilized, the oil sand resources can be consumed for hundreds of years in the world.

The exploitation and utilization of oil sand depend on the separation technology of the oil sand, and the existing oil sand separation technology mainly comprises a water washing separation technology, a solvent extraction technology and a dry distillation technology. The dry distillation technology is a combined process for obtaining light oil products by thermal destruction processing, and only a water washing separation technology and a solvent extraction technology are used for extracting asphalt from oil sand.

The water washing separation technology is to use hot water and surfactant to change the wettability of sand surface and make the surface hydrophilic, so as to achieve the purpose of separating sand from asphalt. The method is only suitable for separating hydrophilic oil sand, and for lipophilic oil sand such as Indonesia oil sand, the separation efficiency is low, the water consumption is high, and sewage needs to be treated.

The solvent extraction technology is that according to the similar compatibility principle, organic solvent is used for extracting colloid and asphaltene in oil sand, then the solvent and the asphalt are separated through distillation, and the solvent is recycled. The method is applicable to both hydrophilic and lipophilic oil sands. The disadvantage of this method is also the biggest problem of excessive environmental pollution. Although the separation equipment is closed, a small amount of solvent is still adsorbed on the surface of the gravel, and the separated gravel accumulated in the open air causes certain pollution to the environment.

Disclosure of Invention

The invention aims to overcome the defects of the existing solvent extraction technology and provides a system and a method for extracting road asphalt from oil sand by using a solvent.

The technical means adopted by the invention are as follows.

The invention discloses a system for extracting road asphalt from oil sand by using a solvent, which comprises a rotary drying device, at least two stages of extraction devices, at least two stages of centrifugal separation devices, a rotary burning device and a mixed liquid separation device, wherein the at least two stages of extraction devices are sequentially and alternately connected with the rotary drying device, the mixed liquid separation device is connected with a first-stage centrifugal separation device, and a liquid phase outlet of a final-stage centrifugal separation device is connected with an inlet of the first-stage extraction device in a return connection mode.

Comprises a rotary drying device 11 and a primary extraction device 2, a primary centrifugal separation device 3, a secondary extraction device 5, a secondary centrifugal separation device 6 and a rotary incineration device 10 which are sequentially connected with the rotary drying device; the liquid outlet of the primary centrifugal separation device 3 is connected with a normal pressure separation device 12, the mixed liquid outlet of the normal pressure separation device 12 is connected with a decompression separation device 13, and the decompression separation device 13 comprises a fuel oil outlet and a road asphalt outlet; a solvent inlet of the secondary extraction device 5 is connected with a circulating solvent storage tank 9, and a solvent outlet of the normal-pressure separation device 12 is connected with an inlet or an inlet pipeline of the circulating solvent storage tank 9; the liquid outlet of the secondary centrifugal separation device 6 is connected back to the solvent inlet of the primary extraction device 2.

The flue gas outlet of the rotary incineration device 10 is connected with the rotary drying device 11, and the solid phase outlet is connected with the tailing heat exchange device 21.

The invention also provides a method for extracting road asphalt from oil sand by using a solvent, which comprises the following steps of crushing and screening an oil sand raw material 1, drying the oil sand raw material in a rotary drying device 11, feeding the dried oil sand into a primary extraction device 2, mixing the dried oil sand according to the volume ratio of the solvent to the oil sand being 1 ~: 1, feeding a solid-liquid mixture obtained by extraction into a primary centrifugal separation device 3 for primary centrifugal separation, feeding solid-phase gravel obtained by separation into a secondary extraction device 5, feeding the primary mixed liquid obtained by separation into an atmospheric separation device 12, distilling the atmospheric separation device 12 at normal pressure to obtain the solvent and natural asphalt, recovering the solvent into a circulating solvent storage tank 9, feeding the natural asphalt into a reduced pressure separation device 13 for reduced pressure distillation to obtain fuel oil 15 and road asphalt 16, mixing the solid-phase gravel entering the secondary extraction device 5 according to the volume ratio of the solvent to the solid-sand being 1 ~: 1, feeding the solid-liquid mixture obtained by extraction into a secondary centrifugal separation device 6 for secondary centrifugal separation, feeding the solid-phase oil-containing gravel 8 obtained by separation into a rotary burning device 10, returning the secondary mixed liquid obtained by separation to the primary extraction device 2, and feeding.

Hot flue gas 181 generated after the burning and decomposition of the oil-containing gravel in the rotary burning device 10 is introduced into the rotary drying device 11 to participate in the drying process.

The hot tailings 201 generated after the solid-phase oil-containing gravel 8 is incinerated and decomposed are introduced into a tailing heat exchange device 21.

The drying time of the tailings is 30-60 minutes.

The time for mixing in the reaction kettle of the primary extraction device and the secondary extraction device is 15 ~ 30 minutes.

The solvent is one or a mixture of two or more of naphtha, reformed gasoline, kerosene, diesel oil, crude oil, C ₉ aromatic hydrocarbon, ethylene cracking light diesel oil and fuel oil.

The oil sand has a natural bitumen extraction of 92 ~ 95% and a cyclic solvent loss of 0.5 ~ 2%.

The beneficial effects produced by the invention are as follows.

1. The present invention uses natural bitumen in oil sands to produce a road bitumen component. The fuel oil and road asphalt components are mixed together in the oil sand raw material, also called as 'natural asphalt', but the 'natural asphalt' can not be used as road asphalt, mainly the existence of the fuel oil makes the hardness of the asphalt insufficient.

2. The present invention burns the solvent carried by the oil-containing gravel and the natural asphalt which is not extracted completely to obtain pure tailings, and has no pollution in the process of storage and transportation.

3. The solvent carried by the oil-containing gravel and the natural asphalt which is not extracted completely meet the requirement of burning on energy, the products of solid, liquid and gas generated in each process are utilized, the obtained hot flue gas is used for drying the raw materials, the high-temperature tailings are used for generating electricity, the heat is fully utilized, and the tailings can be used as the raw materials of building materials and the like.

4. The invention solves the problem of producing road asphalt by using natural asphalt and also solves the pollution problem of oil-containing gravel. The method can not only ensure the self-demand of energy, but also remove pollutants at high temperature, and has no pollution to the environment because the equipment operates in a fully-sealed environment.

Drawings

FIG. 1 is a flow chart of the system of the present invention.

[ description of the main symbols ]

1. An oil sand feedstock; 2. a primary extraction device; 3. a first-stage centrifugal separation device; 4. a first-stage mixed liquid storage tank; 5. a secondary extraction device; 6. a secondary centrifugal separation device; 7. a second-stage mixed liquid storage tank; 8. oil-containing gravel; 9. a circulating solvent storage tank; 10. a rotary incineration device; 11. a rotary drying device; 12. a normal pressure separation device; 13. a pressure-reducing separation device; 14. recovering the solvent; 15. a fuel oil; 16. road asphalt; 17. air; 181. hot flue gases; 182. waste flue gas; 19. replenishing solvent, 201, hot tailings; 202. cooling the tailings; 21. tailings heat exchange device.

Detailed Description

The invention protects a system for extracting road asphalt from oil sand by using a solvent.

The system comprises a rotary drying device 11, at least two stages of extraction devices and at least two stages of centrifugal separation devices which are alternately arranged in sequence, a rotary incineration device 10 and a mixed liquid separation device connected with the first-stage centrifugal separation device.

As shown in fig. 1, in the embodiment using two-stage extraction and centrifugation devices, the outlet of the rotary drying device 11 is sequentially connected with a first-stage extraction device 2, a first-stage centrifugal separation device 3, a second-stage extraction device 5, a second-stage centrifugal separation device 6 and a rotary incineration device 10.

The liquid phase outlet of the first-stage centrifugal separation device 3 is connected with the first-stage mixed liquid storage tank 4 and then connected with the normal pressure separation device 12, and the mixed liquid outlet of the normal pressure separation device 12 is connected with the decompression separation device 13.

The solvent inlet of the secondary extraction device 5 is connected with a circulating solvent storage tank 9, and the solvent outlet of the atmospheric separation device 12 is connected with the inlet or inlet pipeline of the circulating solvent storage tank 9. The solid phase outlet of the secondary centrifugal separation device 6 is connected with the rotary burning device 10, and the liquid phase outlet is connected with the secondary mixed liquid storage tank 7 and then is connected to the solvent inlet of the primary extraction device 2.

The rotary drying device 11 is a horizontally rotating drum, and a heat insulation layer and a wear-resistant layer made of high-temperature-resistant materials are arranged on the inner surface of the drum. The rotary incinerator 10 is a horizontally rotating drum, the inner surface of the drum is provided with a heat insulation layer and a wear-resistant layer made of high-temperature resistant materials, and the inlet end of the drum is provided with an auxiliary burner and a pipeline for introducing air. The flue gas outlet of the rotary incineration device 10 is connected with the rotary drying device 11, and the solid phase outlet is connected with the tailing heat exchange device 21.

The separation method and process using the above system are as follows.

Carrying out crushing and screening on the oil sand raw material 1, and drying the screened oil sand in a rotary drying device 11 for 30-60 minutes, wherein the water content is less than 1% after drying.

The dried oil sand is alternately subjected to countercurrent extraction twice and centrifugal separation twice at the temperature of 25 ~ 120 ℃ according to the volume ratio of the solvent to the oil sand of 1 ~ 3:1 to obtain a mixed solution of a circulating solvent and natural asphalt and oil-containing gravel, wherein the circulating solvent is heated to 25 ~ 120 ℃ in a solvent storage tank, and the extraction process is carried out in a reaction kettle of an extraction device.

Specifically, the dried oil sand sequentially enters a primary extraction device 2 and a primary centrifugal separation device 3, the obtained solid gravel enters a secondary extraction device 5, and the obtained primary mixed liquid enters a normal-pressure separation device 12. The mixed solution is separated into solvent and natural asphalt solution in the normal pressure separation device 12, the solvent is recovered to the circulating solvent storage tank for later use, and the natural asphalt solution enters the decompression separation device 13 to be subdivided into fuel oil and road asphalt again. And finishing the separation of the first-stage mixed liquid.

The solid gravel entering the secondary extraction device 5 is mixed with introduced fresh circulating solvent and extracted, and then enters the secondary centrifugal separation device 6, the obtained solid oil-containing gravel 8 enters the rotary incineration device 10 for incineration treatment, and the obtained secondary mixed liquid returns to and is introduced into the primary extraction device 2.

The oily gravel is sent into the rotary incineration device 10 through the solid conveying device, the oily gravel is combusted in the rotary incineration device 10 in direct contact with introduced air, a solvent carried by the oily gravel and natural asphalt not extracted are completely combusted, hot tailings and hot flue gas are obtained, and the combustion time is 20-40 minutes. Hot flue gas is introduced into the rotary drying device 11 to participate in the drying process, and the hot flue gas and the screened oil sand directly flow in parallel in the rotary drying device. The hot tailings generated after the burning and decomposing of the oil-containing gravel are introduced into the tailing heat exchange device 21 to exchange heat energy, and the heat is recycled, for example, the heat-exchange tailing can be used for power generation and the like. The obtained cold tailings 202 are used as a raw material for materials such as buildings.

The stirring time in the reaction kettle of the primary extraction device and the secondary extraction device is 15 ~ 30 minutes.

In the normal pressure separation device 12, the mixed solution of the solvent and the natural asphalt is distilled at normal pressure to obtain a circulating solvent and the natural asphalt, and the circulating solvent is returned to the circulating solvent storage tank 9 for recycling. In the vacuum separation device 13, the natural asphalt is subjected to vacuum distillation to obtain fuel oil and road asphalt components, and the fuel oil is used as fuel for a heating furnace during distillation.

The solvent used in the invention can be one or a mixture of two or more of naphtha, reformed gasoline, kerosene, diesel oil, crude oil, C ₉ aromatic hydrocarbon, ethylene cracking light diesel oil and fuel oil, and the type of the solvent is hydrocarbons.

In the above steps, after the primary extraction and the primary centrifugal separation, 65 ~ 75% of natural bitumen in the dewatered oil sand is extracted and separated, and the rest 25 ~ 35% of natural bitumen and solid oil sand continue to enter the secondary extraction device 5.

98 ~ 99.5.5 percent of circulating solvent and 20 ~ 27 percent of natural asphalt which are separated from a liquid phase outlet of the secondary centrifugal separation device 6 enter a secondary mixed liquid storage tank 7, then flow back to the primary extraction and separation device to participate in primary extraction and separation, and enter a primary mixed liquid storage tank 4 together with 65 ~ 75 percent of natural asphalt, and finally the primary mixed liquid contains 92 ~ 95 percent of natural asphalt in oil sand.

The solid phase oil-containing grit 8 obtained from the two-stage centrifugal separation unit 6 contains 0.5 ~ 2% of the circulating solvent and the remainder 5 ~ 8% of the natural asphalt, the remainder being grit.

The invention sets two-stage extraction and centrifugation, the extraction rate of the natural asphalt can reach 92 ~ 95% (depending on the composition of the solvent), if the extraction rate is three-stage, the extraction rate can reach 96 ~ 98%, and the economical efficiency and other factors are comprehensively considered in actual production.

Compared with the method that a storage tank is adopted to directly provide the solvent, the method that the secondary mixed liquid is adopted to provide the solvent for the primary extraction device 2 has the advantages that the solvent is used in a countercurrent mode, the secondary mixed liquid is obtained after the circulating solvent extracts the gravel subjected to primary centrifugation, the gravel subjected to primary centrifugation contains natural asphalt accounting for 25 ~% of the natural asphalt in the oil sand raw material, 20 ~% of the natural asphalt is dissolved out after the secondary extraction, the mixed liquid and 98 ~ 99.5% of the circulating solvent form the secondary mixed liquid, the mixed liquid has certain dissolving capacity and is used as the solvent of the primary extraction device, the primary mixed liquid mainly extracts the oil sand raw material, and countercurrent extraction is formed in such a way, namely the oil sand is from top to bottom, and the solvent is from bottom.

The following are specific examples of the above-described method.