阅读说明：本技术 一种油页岩分级热解制备页岩油的装置及方法 (Device and method for preparing shale oil through oil shale graded pyrolysis ) 是由 王庆元 汤奕婷 于清江 于 2020-05-21 设计创作，主要内容包括：本发明提供了一种油页岩分级热解制备页岩油的装置及方法,所述装置包括主提升管、辅助提升管、页岩烧焦器、气固分离单元和油气回收单元；所述主提升管和辅助提升管并列设置,主提升管向上延伸至气固分离单元内,辅助提升管向上延伸、从外侧连接至气固分离单元上部,气固分离单元的出口与页岩烧焦器相连,页岩烧焦器的出口与主提升管的中部、辅助提升管的下部均相连,油气回收单元的气体出口与主提升管、辅助提升管均相连。本发明通过主提升管、辅助提升管的设置,将油页岩的热解进行分级控制,从而便于不同反应阶段工艺条件的调节,保证油页岩的热解过程及油品回收更加充分,实现页岩油收率最大化；所述装置热量循环利用,热量利用率高。(The invention provides a device and a method for preparing shale oil by performing staged pyrolysis on oil shale, wherein the device comprises a main lifting pipe, an auxiliary lifting pipe, a shale charring device, a gas-solid separation unit and an oil-gas recovery unit; the main lifting pipe and the auxiliary lifting pipe are arranged in parallel, the main lifting pipe extends upwards into the gas-solid separation unit, the auxiliary lifting pipe extends upwards and is connected to the upper portion of the gas-solid separation unit from the outer side, an outlet of the gas-solid separation unit is connected with the shale singer, an outlet of the shale singer is connected with the middle portion of the main lifting pipe and the lower portion of the auxiliary lifting pipe, and a gas outlet of the oil-gas recovery unit is connected with the main lifting pipe and the auxiliary lifting pipe. According to the invention, through the arrangement of the main lifting pipe and the auxiliary lifting pipe, the pyrolysis of the oil shale is controlled in a grading manner, so that the adjustment of process conditions at different reaction stages is facilitated, the pyrolysis process and the oil recovery of the oil shale are ensured to be more sufficient, and the maximization of the oil yield of the shale is realized; the device has the advantages of cyclic utilization of heat and high heat utilization rate.)

1. A device for preparing shale oil by performing staged pyrolysis on oil shale is characterized by comprising a main lifting pipe, an auxiliary lifting pipe, a shale singeing device, a gas-solid separation unit and an oil-gas recovery unit;

the gas-solid separation device comprises a main lifting pipe, an auxiliary lifting pipe, a shale burning device, an oil-gas recovery unit and an oil-gas recovery unit, wherein the main lifting pipe and the auxiliary lifting pipe are arranged in parallel, the main lifting pipe upwards extends into the gas-solid separation unit, the auxiliary lifting pipe upwards extends and is connected to the upper portion of the gas-solid separation unit from the outer side, the lower outlet of the gas-solid separation unit is connected with the inlet of the shale burning device, the lower outlet of the shale burning device is connected with the middle portion of the main lifting pipe and the lower portion of the.

2. The apparatus of claim 1, wherein the gas-solid separation unit comprises a settling separator;

preferably, a cyclone separator is arranged at the upper part in the settling separator;

preferably, the sedimentation separator comprises an upper section of cylinder and a lower section of cylinder, and the upper section of cylinder and the lower section of cylinder are arranged concentrically or eccentrically;

preferably, the diameter of the upper section cylinder is larger than that of the lower section cylinder;

preferably, a gas stripping ring pipe is arranged in the lower section cylinder body;

preferably, the lower part of the upper section cylinder is connected to the lower part of the main riser by arranging a semicoke riser pipe;

preferably, the lower part of the lower cylinder is connected with the inlet of the shale burner through a semicoke inclined tube.

3. The apparatus of claim 1 or 2, wherein the shale-charrer is internally and/or externally provided with a gas-solid separator;

preferably, the shale singeing device is connected with the middle part of the main riser through a first heat carrier descending pipe and is connected with the lower part of the auxiliary riser through a second heat carrier descending pipe;

preferably, a coke-burning temperature-control heat collector is arranged outside the shale coke burner and is connected in two directions;

preferably, the lower outlet of the scorching temperature-control heat extractor is connected with a shale ash cooler;

preferably, an outlet at the top of the shale burning device is sequentially connected with a smoke machine and a waste heat recovery device.

4. The apparatus of any one of claims 1 to 3, further comprising a mill drying unit, an outlet of the mill drying unit being connected to an inlet of the main riser;

preferably, the outlet flue gas of the waste heat recovery device is connected to a flue gas cooler through a milling and drying unit.

5. The device according to any one of claims 1 to 4, wherein an upper outlet of the oil gas recovery unit is connected with two pipelines, one pipeline is connected with inlets of the main riser and the auxiliary riser through a circulating compressor, and the other pipeline produces pyrolysis dry gas;

preferably, a lower outlet of the oil and gas recovery unit produces shale oil.

6. A method for producing shale oil using an apparatus according to any of claims 1 to 5, the method comprising the steps of:

(1) the oil shale raw material enters a main lifting pipe under the action of carrier gas to sequentially carry out primary pyrolysis and secondary pyrolysis reactions, and a heat carrier is introduced into the middle of the main lifting pipe in the pyrolysis process;

(2) separating the two-stage pyrolysis reaction products to obtain pyrolysis oil gas and shale semicoke, wherein the shale semicoke is mixed with shale ash from an auxiliary riser in the sedimentation process to carry out three-stage pyrolysis;

(3) fractionating the pyrolysis oil gas obtained in the step (2) to obtain pyrolysis dry gas and shale oil, and returning part of the pyrolysis dry gas to the step (1) and the step (2) to be used as carrier gas;

(4) and (3) carrying out a coking reaction on the shale semicoke subjected to the three-stage pyrolysis in the step (2), and returning the obtained heat carrier to the main riser in the step (1) and the auxiliary riser in the step (2).

7. The method of claim 6, wherein the oil shale raw material in step (1) is first pulverized and dried to obtain shale powder;

preferably, the temperature of the primary pyrolysis in the step (1) is 300-400 ℃;

preferably, the temperature of the secondary pyrolysis in the step (1) is 500-550 ℃;

preferably, the pressure of the primary pyrolysis and the secondary pyrolysis in the step (1) is 0-0.3 MPaG;

preferably, the total time of the primary pyrolysis and the secondary pyrolysis in the step (1) is 2-5 s;

preferably, the heat carrier is shale ash from a shale charrer, and the temperature is 600-800 ℃.

8. The process of claim 6 or 7, wherein the separation of step (2) is performed in a settling separator;

preferably, the settling separator comprises an upper section cylinder and a lower section cylinder, and the lower part of the upper section cylinder separates part of the shale semicoke to enter the lower part of the main riser to be used as a heat carrier for primary pyrolysis;

preferably, the three-stage pyrolysis in the step (2) is carried out in both the upper section cylinder and the lower section cylinder;

preferably, the oil gas entrained in the shale semicoke in the three-stage pyrolysis process in the step (2) is stripped;

preferably, the temperature of the tertiary pyrolysis in the step (2) is 520-600 ℃;

preferably, the residence time of the tertiary pyrolysis in the step (2) is 30-600 s.

9. The method of any one of claims 6-8, wherein said fractionating of step (3) is performed in an oil and gas recovery unit;

preferably, the pyrolysis oil gas in the step (3) is subjected to quenching and fractionation to obtain pyrolysis dry gas and shale oil;

preferably, the pyrolysis dry gas returned in the step (3) accounts for 80-95% of the total amount of the pyrolysis dry gas.

10. The method according to any one of claims 6 to 9, wherein the shale semicoke of step (4) enters a shale charrer for charring reaction;

preferably, the temperature of the scorching reaction in the step (4) is 600-800 ℃;

preferably, air is introduced into the shale charring device;

preferably, fuel is also introduced into the shale combustor;

preferably, the temperature in the shale charring device is controlled by a charring temperature-control heat collector, and a solid material fluidization heat-collecting mode is adopted;

preferably, the oxygen content of the flue gas obtained by the scorching reaction in the step (4) is 2-5%;

preferably, the flue gas obtained by the scorching reaction in the step (4) is subjected to gas-solid separation, potential energy recovery and waste heat recovery in sequence, and the temperature of the flue gas is reduced to 300-370 ℃;

preferably, the flue gas after waste heat recovery is used as dry gas for milling and drying the oil shale raw material in the step (1), the temperature of the flue gas is reduced to 100-130 ℃, and then the flue gas is cooled to recover moisture and is discharged;

preferably, a part of shale ash obtained by the scorching reaction in the step (4) is used as a heat carrier, and the other part is cooled and recovered;

preferably, the cooling mode is dry cooling and is carried out by adopting a fluidized cooler or a plate cooler;

preferably, the cooling medium comprises any one of cooling water, deoxygenated water or molten salt or a combination of at least two of the above.

Technical Field

The invention belongs to the technical field of fossil energy utilization, and relates to a device and a method for preparing shale oil by oil shale graded pyrolysis.

Background

The oil shale is a sedimentary rock containing organic matters, shale oil, dry distillation gas and the like can be generated through heating and dry distillation, the oil shale belongs to unconventional oil and gas resources, and with increasing shortage of petroleum resources, shale oil is produced by using an oil shale dry distillation technology and becomes an important scheme for replacing and supplementing the petroleum resources, so that the development of an oil shale comprehensive utilization technology is developed, the development of the oil shale industry is promoted, and the strategic significance for relieving energy shortage and improving an energy structure is realized.

At present, a plurality of countries in the world research oil shale utilization technology, the oil shale dry distillation technology can be divided into an external heating type and an internal heating type according to heating modes, the former has the problems that the thermal efficiency is low, a secondary decomposition device of volatile products is difficult to enlarge the size and the like, the research is less, the latter utilizes a heat carrier to directly transfer heat, the defects of the external heating type can be overcome, the oil shale dry distillation technology has the advantages of uniform heating, relatively less secondary decomposition and the like, and is favored by researchers.

CN 106833714A discloses a process for refining oil shale or oil sand by downward circulating bed millisecond pyrolysis, wherein the oil shale or oil sand is dried and lifted by a flue gas lift pipe and subjected to gas-solid fractional separation at the top, the flue gas is discharged outside, fine particles enter a semicoke returning device, large and medium particles are rapidly heated and pyrolyzed with high-temperature circulating ash at the top end of a downward pyrolysis reactor, pyrolysis oil gas passes through a fractionating tower to obtain different fractions of oil products and dry gas, and hot ash and semicoke enter a coke burning lift pipe for combustion and heating; after gas-solid separation, the high-temperature hot ash after combustion is introduced into a flue gas riser to lift and dry the oil shale or the oil sand, and part of large and medium particle hot ash enters a descending pyrolysis reactor or a fluidized heat collector for secondary combustion; the process is mainly characterized in that hot ash and semicoke react in a burning riser, the primary pyrolysis of the oil shale or oil sand raw material is incomplete, a plurality of devices are adopted for respectively carrying out pyrolysis, the required separation steps are more, and the process is more complex.

CN 103131444a discloses a fluidized bed dry distillation method and device for oil shale, the method comprises: mixing an oil shale raw material and a high-temperature heat carrier in a mixing tube, then feeding the mixture into a bed-type dry distillation reactor for dry distillation reaction, steam-stripping the formed mixed semicoke in a steam stripping section to obtain entrained oil gas, removing heat and cooling one part of the steam-stripped mixed semicoke, discharging the cooled mixed semicoke out of a dry distillation device, feeding the other part of the steam-stripped mixed semicoke into a tubular carbon burning device for carbon burning, and feeding the high-temperature heat carrier and flue gas generated after the carbon burning into a flue gas removal tank for separation; the method only carries out a section of dry distillation process, the mixing of the solid heat carrier and the solid raw material is not beneficial to heat transfer, the oil shale conversion is not thorough, and the shale oil yield is not high.

In summary, for the process of preparing shale oil from oil shale raw materials, the pyrolysis process needs to be controlled in a grading manner, and the process is adjusted according to products at different stages, so that the overall conversion degree of the raw materials is improved, and the product yield is maximized.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide a device and a method for preparing shale oil by performing staged pyrolysis on oil shale, wherein the device controls the pyrolysis process of the oil shale in a staged manner, so that the processes in different reaction stages are all in a reasonable range, the pyrolysis process of the oil shale and the recovery of oil products are more sufficient, and the yield of the shale oil is maximized.

In order to achieve the purpose, the invention adopts the following technical scheme:

on one hand, the invention provides a device for preparing shale oil by performing staged pyrolysis on oil shale, which comprises a main lifting pipe, an auxiliary lifting pipe, a shale singeing device, a gas-solid separation unit and an oil-gas recovery unit;

the gas-solid separation device comprises a main lifting pipe, an auxiliary lifting pipe, a shale burning device, an oil-gas recovery unit and an oil-gas recovery unit, wherein the main lifting pipe and the auxiliary lifting pipe are arranged in parallel, the main lifting pipe upwards extends into the gas-solid separation unit, the auxiliary lifting pipe upwards extends and is connected to the upper portion of the gas-solid separation unit from the outer side, the lower outlet of the gas-solid separation unit is connected with the inlet of the shale burning device, the lower outlet of the shale burning device is connected with the middle portion of the main lifting pipe and the lower portion of the.

According to the invention, the oil shale graded pyrolysis device controls the pyrolysis of the oil shale in a graded manner through the arrangement of the main riser and the auxiliary riser, so that the conditions of different reaction stages are conveniently controlled, the utilization rate of a pyrolysis product is improved through the shale burner, the product is used as a heat carrier of the pyrolysis reaction, the oil shale pyrolysis is more thorough, the oil recovery is more sufficient, the secondary reaction and entrainment loss of shale oil are avoided, and the yield of the shale oil is improved; meanwhile, the device can recycle heat and has high heat utilization rate.

The following technical solutions are preferred technical solutions of the present invention, but not limited to the technical solutions provided by the present invention, and technical objects and advantageous effects of the present invention can be better achieved and achieved by the following technical solutions.

As a preferred technical scheme of the invention, the gas-solid separation unit comprises a settling separator.

Preferably, a cyclone separator is arranged at the inner upper part of the settling separator.

According to the invention, the main riser extends into the settling separator, and the gas-solid separator is arranged at the outlet of the main riser, so that the pyrolysis oil gas and the shale semicoke can be quickly separated.

Preferably, the sedimentation separator comprises an upper section of cylinder and a lower section of cylinder, and the upper section of cylinder and the lower section of cylinder are arranged concentrically or eccentrically.

Preferably, the diameter of the upper section cylinder is larger than that of the lower section cylinder.

Preferably, a gas stripping ring pipe is arranged in the lower cylinder.

According to the invention, the settling separator is structurally arranged, so that the separated shale semicoke can be further pyrolyzed under the action of high-temperature shale ash, the gas lift ring pipe in the cylinder body forms a pyrolysis bed layer, the introduction of a gas lift medium can maintain the fluidization state of the pyrolysis bed layer to provide partial heat for pyrolysis of the shale semicoke, and meanwhile, pyrolysis oil gas carried by the shale semicoke is subjected to gas lift, so that the yield of the pyrolysis oil gas is improved.

In the present invention, the stripping medium may be selected from any one of steam, oil-free pyrolysis gas or inert gas, or a combination thereof.

Preferably, the lower part of the upper section cylinder is connected to the lower part of the main riser by arranging a semicoke riser pipe.

Preferably, the lower part of the lower cylinder is connected with the inlet of the shale burner through a semicoke inclined tube.

According to the structure of the sedimentation separator, the shale semicoke is subjected to three-stage pyrolysis in the sedimentation process, then part of the shale semicoke can leave from the upper section of the cylinder body and is used as a heat carrier for the first-stage pyrolysis, and the other part of the shale semicoke is sedimentated to the lower section of the cylinder body and enters the shale charring device for charring reaction.

As a preferable technical scheme of the invention, a gas-solid separator is arranged inside and/or outside the shale singeing device.

Preferably, the shale-burning device is connected with the middle part of the main riser through a first heat carrier descending pipe and is connected with the lower part of the auxiliary riser through a second heat carrier descending pipe.

Preferably, a coke-burning temperature-control heat collector is arranged on the outer side of the shale coke burner and is in bidirectional connection with the shale coke burner.

Preferably, the lower outlet of the scorching temperature-control heat extractor is connected with a shale ash cooler.

Preferably, an outlet at the top of the shale burning device is sequentially connected with a smoke machine and a waste heat recovery device.

In the invention, air is introduced into the shale charring device to ensure that the shale semicoke is fully combusted, and the temperature is controlled by the charring temperature control heat collector, so that the generation of nitrogen oxides is reduced while the complete charring is ensured.

As a preferred technical scheme, the device also comprises a milled powder drying unit, and an outlet of the milled powder drying unit is connected with an inlet of the main riser.

Preferably, the outlet flue gas of the waste heat recovery device is connected to a flue gas cooler through a milling and drying unit.

In the invention, the oil shale raw material needs to be ground to a proper particle size range and is dried to be beneficial to full pyrolysis, the smoke generated in the coke burner is used as drying gas, but the smoke has high temperature and is not suitable for direct use, and the smoke is firstly reduced to a proper temperature through waste heat recovery and the like and then is used for drying the oil shale.

As a preferred technical scheme of the invention, an upper outlet of the oil gas recovery unit is connected with two pipelines, one pipeline is connected with inlets of the main riser and the auxiliary riser through a circulating compressor, and the other pipeline generates pyrolysis dry gas.

Preferably, a lower outlet of the oil and gas recovery unit produces shale oil.

In another aspect, the present invention provides a method for preparing shale oil using the above apparatus, the method comprising the steps of:

(1) the oil shale raw material enters a main lifting pipe under the action of carrier gas to sequentially carry out primary pyrolysis and secondary pyrolysis reactions, and a heat carrier is introduced into the middle of the main lifting pipe in the pyrolysis process;

(2) separating the two-stage pyrolysis reaction products to obtain pyrolysis oil gas and shale semicoke, wherein the shale semicoke is mixed with shale ash from an auxiliary riser in the sedimentation process and heated to carry out three-stage pyrolysis;

(3) fractionating the pyrolysis oil gas obtained in the step (2) to obtain pyrolysis dry gas and shale oil, and returning part of the pyrolysis dry gas to the step (1) and the step (2) to be used as carrier gas;

(4) and (3) carrying out a coking reaction on the shale semicoke subjected to the three-stage pyrolysis in the step (2), and returning the obtained heat carrier to the main riser in the step (1) and the auxiliary riser in the step (2).

As a preferable technical scheme of the invention, the oil shale raw material in the step (1) is firstly ground and dried to obtain shale powder. The shale powder has a particle size of not more than 3mm, for example 3mm, 2.5mm, 2mm, 1.5mm or 0.5mm, but is not limited to the recited values, and other values not recited within the range of values are equally applicable.

Preferably, the temperature of the primary pyrolysis in step (1) is 300 to 400 ℃, such as 300 ℃, 320 ℃, 340 ℃, 360 ℃, 380 ℃ or 400 ℃, but not limited to the recited values, and other values not recited in the range of the values are also applicable.

Preferably, the temperature of the secondary pyrolysis in step (1) is 500 to 550 ℃, for example 500 ℃, 510 ℃, 520 ℃, 530 ℃, 540 ℃, 550 ℃ or the like, but is not limited to the recited values, and other values not recited in the range of the values are also applicable.

Preferably, the pressure of the primary pyrolysis and the secondary pyrolysis in step (1) is 0 to 0.3MPaG, such as 0, 0.05MPaG, 0.1MPaG, 0.15MPaG, 0.2MPaG, 0.25MPaG, 0.3MPaG, etc., but is not limited to the recited values, and other values not recited in the range of the values are also applicable.

Preferably, the total time of the primary pyrolysis and the secondary pyrolysis in step (1) is 2 to 5s, such as 2s, 2.5s, 3s, 3.5s, 4s, 4.5s, or 5s, but not limited to the recited values, and other values not recited in the range of the values are also applicable.

According to the invention, oil gas contained in the shallow surface of the powder oil shale is gasified and diffused into the lifting gas during primary pyrolysis, the temperature is further increased during secondary pyrolysis, a large amount of oil gas contained in the oil shale is pyrolyzed out, the temperature of the whole lifting pipe is rapidly increased, and the reaction time is short.

Preferably, the heat carrier is shale ash from a shale-burning device, and the temperature is 600-800 ℃, such as 600 ℃, 650 ℃, 700 ℃, 750 ℃ or 800 ℃, but not limited to the recited values, and other values not recited in the range of the recited values are also applicable.

As a preferred technical scheme of the invention, the separation in the step (2) is carried out in a settling separator.

Preferably, the settling separator comprises an upper section cylinder and a lower section cylinder, and the lower part of the upper section cylinder separates part of the shale semicoke to enter the lower part of the main riser to be used as a heat carrier for primary pyrolysis.

Preferably, the three-stage pyrolysis in the step (2) is performed in both the upper section cylinder and the lower section cylinder.

Preferably, the oil gas entrained in the shale semicoke in the three-stage pyrolysis process in the step (2) is stripped.

Preferably, the temperature of the tertiary pyrolysis in step (2) is 520 to 600 ℃, for example 520 ℃, 530 ℃, 540 ℃, 550 ℃, 560 ℃, 570 ℃, 580 ℃, 590 ℃ or 600 ℃, but not limited to the recited values, and other values not recited in the range of the values are also applicable.

Preferably, the residence time of the tertiary pyrolysis in step (2) is 30 to 600s, such as 30s, 60s, 100s, 150s, 200s, 300s, 400s, 500s, or 600s, but not limited to the recited values, and other values not recited in the range of the values are also applicable.

In the invention, the three-stage pyrolysis is carried out in the settling separator, the shale semicoke separated at the outlet of the main riser enters the bed layer pyrolysis section under the action of gravity, and is mixed with the shale ash lifted by the auxiliary riser to be heated for deep pyrolysis, and as the reaction temperature is further increased, the reaction time is prolonged, and the oil shale which is not completely pyrolyzed in the original riser is thoroughly pyrolyzed.

As a preferred technical scheme of the invention, the fractionation in the step (3) is carried out in an oil gas recovery unit.

Preferably, the pyrolysis oil gas in the step (3) is subjected to quenching and fractionation to obtain pyrolysis dry gas and shale oil.

Preferably, the pyrolysis dry gas returned in step (3) accounts for 80-95% of the total pyrolysis dry gas, such as 80%, 82%, 85%, 88%, 90%, 92%, or 95%, but not limited to the recited values, and other values not recited in the range of the recited values are also applicable.

As a preferable technical scheme of the invention, the shale semicoke in the step (4) enters a shale charring device for charring reaction.

Preferably, the temperature of the scorch reaction in step (4) is 600-800 ℃, such as 600 ℃, 640 ℃, 670 ℃, 700 ℃, 720 ℃, 750 ℃, 780 ℃ or 800 ℃, but not limited to the recited values, and other values not recited in the range of values are also applicable.

Preferably, air is introduced into the shale charrer.

Preferably, fuel is also introduced into the shale combustor.

Preferably, the temperature in the shale-burning device is controlled by a burning temperature-control heat collector, and a solid material fluidization heat-collecting mode is adopted.

Preferably, the oxygen content of the flue gas obtained by the scorch reaction in step (4) is 2-5%, such as 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%, but not limited to the recited values, and other values not recited in the range of the recited values are also applicable.

Preferably, the flue gas obtained from the scorching reaction in step (4) is sequentially subjected to gas-solid separation, potential energy recovery, and waste heat recovery, and the temperature of the flue gas is reduced to 300-370 ℃, for example, 300 ℃, 310 ℃, 320 ℃, 330 ℃, 340 ℃, 350 ℃, 360 ℃, or 370 ℃, but not limited to the recited values, and other unrecited values in the range of the values are also applicable.

Preferably, the flue gas after recovering the waste heat is used as a drying gas for milling and drying the oil shale raw material in the step (1), the temperature of the flue gas is reduced to 100-130 ℃, for example, 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, 125 ℃ or 130 ℃, and the flue gas is cooled to recover the moisture and then is discharged.

In the invention, the water content of the oil shale raw material is improved by drying the smoke, the water is condensed and recovered after the smoke is cooled to the room temperature, and the gas is discharged.

Preferably, a part of shale ash obtained by the scorching reaction in the step (4) is used as a heat carrier, and the other part is cooled and recovered.

Preferably, the cooling mode is dry cooling and is performed by adopting a fluidized cooler or a plate cooler.

Preferably, the cooling medium comprises any one of cooling water, deoxygenated water or molten salt or a combination of at least two of the following, typical but non-limiting examples being: combinations of cooling water and deoxygenated water, combinations of deoxygenated water and molten salt, combinations of cooling water, deoxygenated water and molten salt, and the like.

Compared with the prior art, the invention has the following beneficial effects:

(1) according to the device, the pyrolysis of the oil shale is controlled in a grading manner through the arrangement of the main lifting pipe and the auxiliary lifting pipe and the arrangement of the position relation between the main lifting pipe and the gas-solid separation unit, so that the adjustment of process conditions at different reaction stages is facilitated, the pyrolysis process and the oil recovery of the oil shale are more sufficient, the shale oil yield is maximized, the yield of the aluminum retort dry distillation oil can reach 90-130%, and the shale oil yield is improved by more than 50% compared with that of the common shale dry distillation technology;

(2) the shale charring device is beneficial to full utilization of shale semicoke, and the charred product is used as a heat carrier for pyrolysis reaction, so that the heat utilization rate is high.

Drawings

FIG. 1 is a schematic structural diagram of an apparatus for preparing shale oil by fractional pyrolysis of oil shale according to example 1 of the present invention;

the system comprises a grinding and drying unit 1, a main lifting pipe 2, an auxiliary lifting pipe 3, a settling separator 4, a shale charring device 5, an oil gas recovery unit 6, a semicoke vertical pipe 7, a semicoke inclined pipe 8, a first heat carrier descending pipe 9, a second heat carrier descending pipe 10, a charring temperature-control heat extractor 11, a shale ash cooler 12, a gas-solid separator 13, a smoke machine 14, a waste heat recovery device 15, a smoke cooler 16 and a circulating compressor 17.

Detailed Description

In order to better illustrate the present invention and facilitate the understanding of the technical solutions of the present invention, the present invention is further described in detail below. However, the following examples are only simple examples of the present invention and do not represent or limit the scope of the present invention, which is defined by the claims.

The invention provides a device and a method for preparing shale oil by oil shale graded pyrolysis, wherein the device comprises a main lifting pipe 2, an auxiliary lifting pipe 3, a shale charrer 5, a gas-solid separation unit and an oil gas recovery unit 6;

the gas-solid separation device is characterized in that the main lifting pipe 2 and the auxiliary lifting pipe 3 are arranged in parallel, the main lifting pipe 2 extends upwards into the gas-solid separation unit, the auxiliary lifting pipe 3 extends upwards and is connected to the upper portion of the gas-solid separation unit from the outer side, the lower outlet of the gas-solid separation unit is connected with the inlet of the shale charring device 5, the lower outlet of the shale charring device 5 is connected with the middle portion of the main lifting pipe 2 and the lower portion of the auxiliary lifting pipe 3, the top outlet of the gas-solid separation unit is connected with the inlet of the oil-gas recovery unit 6, and the gas outlet of the oil-gas recovery unit 6 is connected with the inlets of the main.

The following are typical but non-limiting examples of the invention: