CN114133944A

CN114133944A - Oil shale treatment system and treatment method

Info

Publication number: CN114133944A
Application number: CN202111496392.1A
Authority: CN
Inventors: 郑莹; 黄绍通; 杨爱国; 杨新乐; 吴丽佳
Original assignee: Liaoning Technical University
Current assignee: Liaoning Technical University
Priority date: 2021-12-09
Filing date: 2021-12-09
Publication date: 2022-03-04

Abstract

The invention relates to the technical field of oil production from oil shale, in particular to a system and a method for treating oil shale with small particle diameter. The top end of the oil shale dry distillation device is provided with a waterwheel type feeder and an umbrella-shaped object collecting device, a plurality of zigzag roller beds are fixed on the furnace wall inside the oil shale dry distillation device, a gas washing device is connected with the outlet of the umbrella-shaped object collecting device through a dry distillation gas product pipeline, low-temperature gas produced by the oil shale dry distillation device is connected with a gas tank and a superheater through a longitudinal gas distribution air port and a low-temperature gas pipeline, and the bottom of a circulating water tank is connected with the top end of the gas washing device through a circulating water pump and a circulating cooling water pipeline. By adopting the destructive distillation technology of the oil shale with small particle size and small particles, the production cost of oil shale products can be saved, the path length of the oil shale in the furnace can be effectively increased by adopting the zigzag roller bed in the oil shale treatment system and the treatment method thereof, and the paths of the oil shale particles with different particle sizes in the furnace are different.

Description

Oil shale treatment system and treatment method

Technical Field

The invention relates to the technical field of oil production from oil shale, in particular to a system and a method for treating oil shale with small particle diameter.

Background

At present, three kinds of oil shale gas retort independently researched and developed in China exist, the first kind is a smoothing furnace, oil shale particles with the particle size of 12mm-75mm are processed, the oil shale particles with the particle size of less than 12mm generated in mining exceed 20% of the total amount, a large number of small-particle oil shale particles are discarded, and environmental pollution is caused; the recovery rate of oil is 65% due to combustion in the smoothing furnace, the calorific value of gas produced by the furnace body is reduced due to air introduced into the furnace, and the calorific value is 4000kJ/Nm for high speed plantation, so that the method is difficult to utilize. The second is a rare gas combustion type round furnace improved by a rare gas combustion type square furnace, gas is used as a heat carrier to process oil shale particles with the particle size of 15mm-75mm, and a large amount of oil shale particles with small particle size are discarded; the recovery rate of oil is low; the gas distribution in the furnace is not uniform, so that the dry distillation of partial oil shale particles is incomplete, and the oil shale with high water content is difficult to process. The third is a birchdian gas full-circulation retort furnace, which takes gas as a heat carrier to process oil shale particles with the particle size of 6mm-50mm, the recovery rate of oil is higher than 90 percent, and the birchdian gas full-circulation retort furnace is in the leading level in the world. And an Australian ATP furnace introduced from abroad takes solids as heat carriers and can treat oil shale particles smaller than 16mm, but a cyclone separator for separating the heat carriers and dry distillation products in the ATP process causes consumption of a large amount of high-grade energy, and the ATP furnace is huge in furnace body and expensive in manufacturing cost. At present, only Chinese birch type gas full-cycle gas retort furnaces for performing fractional dry distillation on oil shale particles according to particle sizes are used all over the world, but the actual production is only divided into two grades of 6mm-20mm and 20mm-50 mm. The dry distillation time of the oil shale particles is increased along with the increase of the particle size, when the oil shale particles with different particle sizes are subjected to dry distillation in the same furnace, the oil shale particles which are subjected to dry distillation occupy the space inside the hearth, so that the daily treatment capacity of the oil shale dry distillation furnace cannot be improved, and the heat brought by circulating gas is wasted. The oil shale with small particle size becomes waste materials of most of domestic processes due to the characteristics of the oil shale, so that a large amount of resources are wasted, the cost is increased, and the product lacks competitiveness. The reasons for the difficulty in utilizing the small-particle-size oil shale particles are as follows: the small particles are piled up, so that the heat carrier is unevenly distributed due to poor air permeability and large bed resistance, and the dry distillation of part of the oil shale particles is incomplete; the heating time of the small-particle oil shale cannot be too long, otherwise, the secondary cracking of the shale oil can be caused, the generation of products is reduced, and a large amount of heat is wasted; the small-particle oil shale is easier to cause the thermal disintegration of oil shale particles due to the separation of volatile gases, and smaller oil shale particles are generated, so that the air permeability in the retort is poorer; the small-particle oil shale is easy to excessively dry distill to cause coking of a hearth, so that the operation link is deteriorated, and the maintenance cost of equipment is increased.

Disclosure of Invention

The invention aims to overcome the technical defects and provide the oil shale treatment system and the treatment method which have simple structure, are safe and reliable in use and reduce the production cost of oil shale products.

The technical scheme adopted by the invention for solving the technical problem is as follows: the processing system in the oil shale processing system and the processing method comprises: the oil shale dry distillation device is characterized in that a waterwheel type feeder and an umbrella-shaped object collecting device are arranged at the top end of the oil shale dry distillation device, a hopper is connected above the waterwheel type feeder, a plurality of zigzag roller beds are fixed on the furnace wall in the oil shale dry distillation device, each zigzag roller bed consists of a plurality of rollers, roller gears are arranged on the rollers, intervals are arranged among the rollers, the intervals among the rollers on the same layer are the same, the intervals among the rollers on different layers of the roller beds decrease gradually from top to bottom, a chain is arranged below the roller beds to drive the roller beds to move, a speed distribution box serving as a zigzag roller bed driving device is arranged on the furnace wall of the oil shale dry distillation device at the intersection and the starting position of the zigzag roller beds, and a first layer of transverse gas distribution air ports are horizontally arranged on the furnace wall of the oil shale dry distillation device, A second layer of transverse gas distribution air port, a third layer of transverse gas distribution air port and a longitudinal gas distribution air port, wherein the longitudinal gas distribution air port is arranged below the third layer of transverse gas distribution air port, the transverse gas distribution air port forms an angle with the horizontal direction of the furnace wall of the oil shale dry distillation device, the longitudinal gas distribution air port forms an angle with the vertical direction of the furnace wall of the oil shale dry distillation device, a scraper discharging system is arranged below the oil shale dry distillation device, a water seal pool is arranged below the scraper discharging system corresponding to the furnace wall of the oil shale dry distillation device, the scraper discharging system is connected with the upper part of a semicoke hopper along the upper part of the wall of the water seal pool, the lower parts of the semicoke hopper and a coal briquette hopper are communicated with a pulverizer, the lower end of the pulverizer is communicated with an inner cavity of a powder discharge machine and a semicoke combustion device, a water superheater and a water superheater are arranged above the semicoke combustion device, and a steam turbine is connected above the water superheater through a steam pipeline, a tail gas output pipeline is communicated with the upper right of the semicoke combustion device, an ignition device is arranged below the wall of the semicoke combustion device, a furnace ash waste heat collecting device is arranged below the semicoke combustion device, a multi-stage herringbone baffle is arranged above the furnace ash waste heat collecting device, a heat conducting oil pipeline is arranged inside the multi-stage herringbone baffle, an ash storage chamber is arranged below the multi-stage herringbone baffle in the furnace ash waste heat collecting device, a furnace ash outlet is arranged in the bottom of the furnace ash waste heat collecting device and communicated with the ash storage chamber, the heat conducting oil pipeline sends oil to a heat conducting oil pipeline port on a roller through a heat conducting oil conveying pipeline, a hot oil pump is arranged on the heat conducting oil conveying pipeline, a gas washing device is connected with the outlet of the umbrella-shaped product collecting device through a dry distillation gas product pipeline, the gas washing device is connected with a gas tank through a gas pipeline, and low-temperature gas produced by the oil dry distillation device is connected with the gas tank and a superheater through a longitudinal gas distribution air port and a low-temperature gas pipeline, the first layer of transverse gas distribution air port, the second layer of transverse gas distribution air port and the third layer of transverse gas distribution air port are connected with the superheater through high-temperature gas pipelines, the lower part of the gas washing device is connected with the oil storage tank through shale oil pipelines, the bottom of the gas washing device is connected with the top end of the circulating water tank through a circulating cooling water pipeline, and the bottom of the circulating water tank is connected with the top end of the gas washing device through a circulating water pump and a circulating cooling water pipeline. The oil shale treatment method adopting the device comprises the following steps: firstly, oil shale particles fall onto a Z-shaped roller bed at a constant speed through a waterwheel type feeder, and a material layer is formed on the first layer of the Z-shaped roller bed; secondly, the oil shale enters the upper part of the first layer of the Z-shaped roller bed in the oil shale dry distillation device to complete the first screening, oil shale particles which are positioned below the oil shale particle material layer and are smaller than the distance between rollers fall into the lower layer of the Z-shaped roller bed, and the oil shale particles which are positioned below the oil shale particle layer and above the material layer slide down along the Z-shaped roller bed due to self gravity; the roller bed is driven by the speed distributor to rotate in the direction opposite to the moving direction of the oil shale, oil shale particles are turned by the rollers, the material layer is prevented from being pressed to be compact due to the self gravity, the oil shale particles above the material layer can be favorably leaked downwards, the heat required by the oil shale is derived from high-temperature gas sprayed from a transverse gas distribution air port and heat conducting oil in the rollers, semicoke and low-temperature gas react at the lower half part of the oil shale dry distillation device, the temperature of the low-temperature gas rises, the heat value rises, and the gas in two different directions causes disturbance and forms turbulence in the furnace, so that the heating is more uniform; fourthly, when the oil shale particles enter a second layer of the Z-shaped roller bed, repeating the steps of the first step and the second step;

fifthly, the oil shale particles after dry distillation generate semicoke, the semicoke leaves the Z-shaped roller bed and enters the lower part of the oil shale dry distillation device to meet with low-temperature gas sprayed out from the transverse gas distribution air port and the longitudinal gas distribution air port and complete heat exchange, the temperature of the low-temperature gas is increased, residual carbon in the semicoke is consumed, and partial carbon dioxide in the gas is reduced into carbon monoxide, so that the heat value of the gas is increased.

The invention has the beneficial effects that: the oil shale treatment system and the treatment method can effectively increase the path length of the oil shale in the furnace by adopting the zigzag roller bed, the paths of the oil shale particles with different particle sizes in the furnace are different, the oil shale particle material layer can be disturbed by the rollers, and the phenomena of uneven distribution of heat carriers in the furnace and incomplete dry distillation caused by the oil shale particles with small particle sizes are effectively solved. After the oil shale particles are subjected to thermal disintegration, the oil shale particles can fall into the next layer of roller bed from the rollers after the particle size is reduced, and the air permeability of the bed layer cannot be reduced. Because the time required for the dry distillation of the oil shale with small particle diameter in the dry distillation device is shorter than that of the oil shale with large particle diameter, the secondary cracking of the product is effectively prevented. The dry distillation device is directly used for multi-stage screening, so that the volume of the equipment is reduced. The system utilizes the waste heat of the furnace dust to dry and distill the oil shale, and reduces the energy consumption of the oil shale dry distillation system. The furnace ash produced by the semicoke combustion furnace has a high temperature higher than 900 ℃, and is an unavailable waste heat resource.

Drawings

The following description is made in detail by way of example with reference to the accompanying drawings.

Fig. 1 is a schematic diagram of an equipment structure of an oil shale processing system and a processing method.

Fig. 2 is an enlarged view of the structure at I in fig. 1.

Fig. 3 is a diagram showing the relationship between the drum structure and the connecting members in fig. 1.

In the figure, 1-oil shale dry distillation device; 1-1-hopper; 1-2-water wheel type feeder; 1-3-umbrella-shaped product collecting device; 1-4-speed distribution box; 1-5-roller bed; 1-6-chain; 1-7-a first layer of transverse gas distribution air port; 1-8-a second layer of transverse gas distribution air ports; 1-9-third layer transverse gas distribution air port; 1-10-longitudinal gas distribution air port; 1-11-water seal tank; 1-12-a scraper discharge system; 2-a semicoke combustion device; 2-1-superheater; 2-2-a coal block hopper; 2-3-semicoke hopper; 2-4-powder discharging machine; 2-5-a pulverizer; 2-6-ignition device; 2-7-passing hot gas through water; 2-8-steam turbine; 3-a furnace ash waste heat collecting device; 3-1-multi-stage herringbone baffles; 3-2-heat conducting oil pipeline; 3-3-ash storage chamber; 3-4-furnace ash outlet; 4-a gas washing device; 4-1-gas tank; 4-2-circulating water tank; 4-3-circulating water pump; 4-4-oil storage tank; 5-a roller; 5-1-roller gear; 5-2-sealing ring; 5-3-hot oil pump; 5-4-heat conducting oil pipe port; 6-gas pipeline; 7-low temperature gas pipeline; 8-high temperature gas pipeline; 9-tail gas output pipeline; 10-a heat transfer oil conveying pipeline; 11-a dry distillation gas product pipeline; 12-a water vapor line; 13-circulating cooling water pipeline; 14-shale oil pipeline.

Detailed Description

In the embodiment, referring to the attached figures 1-3, the oil shale treatment system and the treatment method are characterized in that a waterwheel type feeder 1-2 and an umbrella-shaped product collecting device 1-3 are arranged at the top end of an oil shale dry distillation device 1 in a treatment device, the umbrella-shaped product collecting device 1-3 is connected with an air extractor, a hopper 1-1 is connected above the waterwheel type feeder 1-2, and a discharge port below the waterwheel type feeder 1-2 is arranged above an upper layer roller bed 1-5. The multilayer roller beds 1-5 are fixedly arranged on the furnace wall of the oil shale dry distillation device 1 in a Z shape, and the furnace wall of the oil shale dry distillation device 1 at the junction of the ends of the Z-shaped roller beds 1-5 is provided with a speed distribution box 1-4 serving as a driving device of the Z-shaped roller beds 1-5. The roller bed 1-5 is composed of a plurality of rollers 5 with spaces between the rollers 5. The intervals between the rollers 5 on the same layer are the same, and the intervals between the rollers 5 on the roller beds 1-5 on different layers decrease gradually from top to bottom layer by layer. The distance between the rollers 5 of the first layer of roller bed 1-5 is 10mm, the distance between the rollers 5 of the second layer of roller bed 1-5 is 8mm, the distance between the rollers of the third layer of roller bed 6mm, the distance between the rollers of the fourth layer of roller bed 4mm, the distance between the rollers of the fifth layer of roller bed 2mm, and the distance between the rollers of the second layer of roller bed 1-5 and the horizontal direction are alpha, and alpha is 15 degrees. Chains 1-6 are arranged below the roller beds 1-5 to drive the roller beds 1-5 to move. A first layer of transverse gas distribution air ports 1-7, a second layer of transverse gas distribution air ports 1-8, a third layer of transverse gas distribution air ports 1-9 and a longitudinal gas distribution air port 1-10 are horizontally arranged on the furnace wall of the oil shale dry distillation device 1 below the third layer of roller bed 1-5 in parallel. The longitudinal gas distribution air ports 1-10 are arranged below the third layer of transverse gas distribution air ports 1-9, the transverse gas distribution air ports and the horizontal direction of the inner wall of the oil shale dry distillation device 1 form an angle of 30 degrees, and the longitudinal gas distribution air ports 1-10 and the vertical direction of the inner wall of the oil shale dry distillation device 1 form an angle of 15 degrees. Gas sprayed out of the transverse gas distribution air ports and the longitudinal gas distribution air ports 1-10 forms turbulent flow in the furnace wall of the oil shale dry distillation device 1, so that heat in the furnace chamber of the oil shale dry distillation device 1 is distributed more uniformly. A scraper discharging system 1-12 is arranged below the oil shale dry distillation device 1, and a water seal pool 1-11 is arranged below the scraper discharging system 1-12 and corresponding to the furnace wall of the oil shale dry distillation device 1. The scraper plate discharging system 1-12 is connected above the semicoke hopper 2-3 along the upper part of the wall of the water seal tank 1-11, and the lower parts of the semicoke hopper 2-3 and the coal block hopper 2-2 are communicated with the pulverizer 2-5. The lower end of the flour mill 2-5 is communicated with the inner cavities of the powder exhauster 2-4 and the semicoke combustion device 2, the upper part in the semicoke combustion device 2 is provided with a superheater 2-1 and a water superheater 2-7, the upper part of the water superheater 2-7 is connected with a steam turbine 2-8 through a steam pipeline 12, and the upper right part of the semicoke combustion device 2 is communicated with a tail gas output pipeline 9. An ignition device 2-6 is arranged below the wall of the semicoke combustion device 2. A furnace ash waste heat collecting device 3 is arranged below the communicated semicoke combustion device 2, a multi-stage herringbone baffle 3-1 is arranged above the furnace ash waste heat collecting device 3, and a heat conducting oil pipeline 3-2 is arranged inside the multi-stage herringbone baffle 3-1. And heat conduction oil is introduced into the heat conduction oil pipeline 3-2, absorbs the residual heat of furnace dust to increase the temperature, and is sent to a roller 5 in the oil shale dry distillation device through a heat conduction oil conveying pipeline 10. An ash storage chamber 3-3 is arranged below the multi-stage herringbone baffle 3-1 in the furnace ash waste heat collecting device 3, a furnace ash output port 3-4 is arranged at the bottom in the furnace ash waste heat collecting device 3 and communicated with the ash storage chamber, and the furnace ash is output from the furnace ash output port 3-4 and then accumulated to a certain amount to be used as a material in the building industry. The heat conduction oil pipeline 3-2 sends oil to a heat conduction oil pipeline port 5-4 on the roller 5 through a heat conduction oil conveying pipeline 10, a heat oil pump 5-3 is arranged on the heat conduction oil conveying pipeline 10, a sealing ring 5-2 is arranged at a seam allowance of the heat conduction oil pipeline port 5-4, and roller gears 5-1 are arranged on two side edges of the roller 5. The gas washing device 4 is connected with the outlet of the umbrella-shaped product collecting device 1-3 through a dry distillation gas product pipeline 11, the gas washing device 4 is connected with the gas tank 4-1 through a gas pipeline 6, and low-temperature gas produced by the oil shale dry distillation device 1 is connected with the gas tank 4-1 and the superheater 2-1 through a longitudinal gas distribution air port 1-10 and a low-temperature gas pipeline 7. The first layer of transverse gas distribution air ports 1-7, the second layer of transverse gas distribution air ports 1-8 and the third layer of gas distribution air ports 1-9 are connected with the superheater 2-1 through high-temperature gas pipelines. The lower part of the gas washing device 4 is connected with an oil storage tank 4-4 through a shale pipeline 14, the bottom of the gas washing device 4 is connected with the top end of a circulating water tank 4-2 through a circulating cooling water pipeline 13, and the bottom of the circulating water tank 4-2 is connected with the top end of the gas washing device 4 through a circulating water pump 4-3 and the circulating cooling water pipeline 13.

The oil shale treatment method adopting the oil shale treatment system comprises the following steps: oil shale particles smaller than 12mm are sent into a hopper 1-1, and the oil shale is sent into the furnace of the oil shale dry distillation device 1 by a water wheel type feeder 1-2 which rotates clockwise. The adoption of the water wheel type feeder 1-2 can uniformly feed and prevent the gas inside the oil shale dry distillation device 1 from leaking. The oil shale particles fed into the oil shale dry distillation apparatus 1 first fall onto the zigzag-shaped upper roller bed 1-5, and the oil shale slides in the rolling direction of the roller bed 1-5. The oil shale is heated by circulating coal gas entering the oil shale dry distillation device 1 in the horizontal direction at 650-750 ℃, when the temperature reaches 550 ℃, rock oil in the oil shale is released and becomes shale semicoke, and the shale semicoke is conveyed to a semicoke recovery system by a conveying belt. The oil shale particles with the particle size smaller than the distance between the rollers 5 directly fall onto the next layer of roller bed 1-5. The oil shale particles roll through the second layer to the fifth layer of the roller beds 1 to 5 in multiple layers, and the oil shale particles are heated more uniformly in all directions. The temperature of the oil shale is continuously increased, when the temperature is increased to 120 ℃, the moisture on the surface is evaporated, when the temperature is increased to 150-170 ℃, the internal adsorption gas is released, and when the temperature is increased to 180 ℃, the organic matter is decomposed. The speed of decomposing the kerogen into the asphalt is greatly increased when the temperature is raised to 350-420 ℃, and when the temperature of the center of the oil shale reaches 550 ℃, the tar in the oil shale is released. When the temperature inside the oil shale reaches 550 ℃, the dry distillation is completed, and the required time is 20-300 s when the particle size of the oil shale is 1-12 mm.

Semicoke particles obtained after the oil shale is subjected to dry distillation fall into a scraper discharging system 1-12 in a water seal tank 1-11, and semicoke is conveyed to a semicoke hopper 2-3 through the scraper discharging system 1-12 and enters a pulverizer 2-5. The coal blocks enter a pulverizer 2-5 through a coal block hopper 2-2, and the semicoke and the coal blocks are pulverized in the pulverizer 2-5 and are mixed and sent to a hearth of a semicoke combustion device 2 through a powder discharge machine 2-4. The pulverized coal and the semicoke are ignited through the ignition device 2-6, the semicoke and the pulverized coal are burnt and reacted in the semicoke combustion device 2 to release a large amount of heat and generate furnace dust, and the heat is absorbed by a working medium in the superheater 2-1. The superheater 2-1 adopts a water superheater 2-7 through which water flows or a gas superheater through which gas flows. Water in the water superheater 2-7 is sent to the steam turbine 2-8 through a steam pipeline 12 to generate electricity, and gas in the superheater 2-1 is sent to the oil shale dry distillation device 1 through nozzles of a transverse gas distribution system 1-7, 1-8 and 1-9 to heat the oil shale. Furnace ash generated by burning the semicoke and the pulverized coal enters the furnace ash waste heat collecting device 3 from an outlet below the semicoke burning device 2. Furnace dust flows down from the multi-stage herringbone baffles 3-1, and the multi-stage herringbone baffles 3-1 shunt and turn over the furnace dust, so that different furnace dust and the multi-stage herringbone baffles 3-1 exchange heat. And a heat conduction oil pipeline 3-2 for circulating heat conduction oil is arranged in the multistage herringbone baffle 3-1, the heat conduction oil collects the waste heat of furnace dust, and the waste heat is sent to a roller 5 in the oil shale dry distillation device 1 through a heat conduction oil conveying pipeline 10, a hot oil pump 5-3 and a heat conduction oil pipeline port 5-4 to provide heat required by dry distillation. After the furnace dust passes through the multi-stage herringbone baffles 3-1, the temperature of the furnace dust is reduced to 700 ℃ and falls into the dust storage chamber 3-3, and the furnace dust is removed from a furnace dust outlet 3-4 at the bottom of the furnace dust waste heat collecting device 3 and used as a building material. An umbrella-shaped product collecting device 1-3 above the oil shale dry distillation device 1 is connected with a gas washing device 4 through a dry distillation gas product pipeline 11, and the top end of the gas washing device 4 is connected with the top end of a gas tank 4-1 through a gas pipeline 6. The lower part of the gas washing device 4 is connected with the upper part of the oil storage tank 4-4 through a shale oil pipeline 14, the bottom of the gas washing device 4 is connected with the top end of the circulating water tank 4-2 through a circulating cooling water pipeline 13, and the bottom of the circulating water tank 4-2 is connected with the top end of the gas washing device 4 through a circulating water pump 4-3 and the circulating cooling water pipeline 13. The first layer of transverse gas distribution air ports 1-7, the second layer of transverse gas distribution air ports 1-8 and the third layer of transverse gas distribution air ports 1-9 on the oil shale dry distillation device 1 are connected with the superheater 2-1 through a high-temperature gas pipeline 8 and then conveyed to the gas tank 4-1 through a pipeline. The low-temperature gas produced by the longitudinal gas distribution tuyere 1-10 is conveyed to the gas tank 4-1 through a low-temperature gas pipeline 7.

In the description of the present embodiment, it is to be understood that the terms "left", "upper", "lower", and the like, which indicate the orientation or positional relationship, or the orientation or positional relationship shown on the basis of the drawings, are merely for convenience of description of the present invention and are not to be construed as limiting the present invention.

Claims

1. An oil shale processing system, the processing system comprising: the oil shale dry distillation device is characterized in that a water wheel type feeder (1-2) and an umbrella-shaped object collecting device (1-3) are arranged at the top end of the oil shale dry distillation device (1), a hopper (1-1) is connected above the water wheel type feeder (1-2), a plurality of Z-shaped roller beds (1-5) are fixed on the wall of the oil shale dry distillation device (1), each Z-shaped roller bed (1-5) is composed of a plurality of rollers (5), roller gears (5-1) are arranged on the rollers (5), intervals are arranged among the rollers (5), the intervals among the rollers (5) on the same layer are the same, and the intervals among the rollers (5) on different layers of the roller beds (1-5) are gradually decreased from top to bottom, chains (1-6) are arranged below the roller beds (1-5) to drive the roller beds (1-5) to move, speed distribution boxes (1-4) are arranged on the furnace wall of the oil shale dry distillation device (1) at the intersection and the starting position of the Z-shaped roller beds (1-5) to be used as driving devices of the Z-shaped roller beds (1-5), a first layer of transverse gas distribution air ports (1-7), a second layer of transverse gas distribution air ports (1-8), a third layer of transverse gas distribution air ports (1-9) and a longitudinal gas distribution air port (1-10) are horizontally arranged on the furnace wall of the oil shale dry distillation device (1) in parallel, the longitudinal gas distribution air ports (1-10) are arranged below the third layer of transverse gas distribution air ports (1-9), and the transverse gas distribution air ports form an angle with the horizontal direction of the oil shale dry distillation device, the vertical direction of a longitudinal gas distribution air port (1-10) and the furnace wall of the oil shale dry distillation device (1) forms an angle, a scraper discharging system (1-12) is arranged below the oil shale dry distillation device (1), a water seal pool (1-11) is arranged below the scraper discharging system (1-12) and corresponding to the furnace wall of the oil shale dry distillation device (1), the scraper discharging system (1-12) is connected above a semicoke hopper (2-3) along the upper part of the wall of the water seal pool (1-11), the lower parts of the semicoke hopper (2-3) and a coal block hopper (2-2) are communicated with a flour mill (2-5), the lower end of the flour mill (2-5) is communicated with a powder discharging machine (2-4) and the inner cavity of the semicoke combustion device (2), a superheater (2-1) and a water superheater (2-7) are arranged above the semicoke combustion device (2), a steam turbine (2-8) is connected above a water superheater (2-7) through a steam pipeline (12), a tail gas output pipeline (9) is communicated with the upper right side of a semicoke combustion device (2), an ignition device (2-6) is arranged below the wall of the semicoke combustion device (2), a furnace ash waste heat collecting device (3) is arranged below the communicated semicoke combustion device (2), a multi-stage herringbone baffle plate (3-1) is arranged above the furnace ash waste heat collecting device (3), a heat conducting oil pipeline (3-2) is arranged inside the multi-stage herringbone baffle plate (3-1), an ash storage chamber (3-3) is arranged below the multi-stage herringbone baffle plate (3-1) in the furnace ash waste heat collecting device (3), a furnace ash outlet (3-4) is arranged at the bottom of the furnace ash waste heat collecting device (3) and communicated with the ash storage chamber (3-3), the heat conduction oil pipeline (3-2) sends oil to a heat conduction oil pipeline port (5-4) on the roller (5) through a heat conduction oil conveying pipeline (10), a heat oil pump (5-3) is arranged on the heat conduction oil conveying pipeline (10), a gas washing device (4) is connected with an outlet of an umbrella-shaped product collecting device (1-3) through a dry distillation gas product pipeline (11), the gas washing device (4) is connected with a gas tank (4-1) through a gas pipeline (6), low-temperature gas produced by the oil shale dry distillation device (1) is connected with the gas tank (4-1) and a superheater (2-1) through a longitudinal gas distribution air port (1-10) and a low-temperature gas pipeline (7), a first layer of transverse gas distribution air ports (1-7), a second layer of transverse gas distribution air ports (1-8) and a third layer of transverse gas distribution air ports (1-9) are connected with the superheater (superheater) through a high-temperature gas pipeline (8) 2-1), an oil storage tank (4-4) is connected below the gas washing device (4) through a shale oil pipeline, the bottom of the gas washing device (4) is connected with the top end of a circulating water tank (4-2) through a circulating cooling water pipeline (13), and the bottom of the circulating water tank (4-2) is connected with the top end of the gas washing device (4) through a circulating water pump (4-3) and the circulating cooling water pipeline (13).

2. The oil shale processing system of claim 1, wherein the oil shale processing method using the apparatus is as follows: firstly, oil shale particles fall onto a Z-shaped roller bed (1-5) at a constant speed through a waterwheel type feeder (1-2), and a material layer is formed on the first layer of the Z-shaped roller bed (1-5); secondly, the oil shale enters the upper part of the first layer of the Z-shaped roller bed (1-5) in the oil shale dry distillation device (1) to complete the first screening, oil shale particles which are positioned below an oil shale particle material layer and are smaller than the distance between the rollers (5) fall into the lower layer of the Z-shaped roller bed (1-5), and the oil shale particles which are positioned below the oil shale particle layer and above the material layer slide down along the Z-shaped roller bed (1-5) due to self gravity; the roller bed (1-5) is driven by the speed distributor (1-4) to rotate in the direction opposite to the moving direction of the oil shale, oil shale particles are turned by the roller (5), the material layer is prevented from being pressed to be compact due to self gravity, the oil shale particles above the material layer are favorably leaked downwards, heat required by the oil shale is sourced from high-temperature gas sprayed from a transverse gas distribution air port and heat conduction oil in the roller (5), semicoke and low-temperature gas react at the lower half part of the oil shale dry distillation device (1), the temperature of the low-temperature gas rises, the heat value rises, the two gases in different directions cause disturbance and form turbulence in the furnace, and the heating is more uniform; fourthly, when the oil shale particles enter a second layer of the Z-shaped roller bed (1-5), repeating the steps of the first step and the second step;

fifthly, the oil shale particles after dry distillation generate semicoke, leave the Z-shaped roller bed (1-5), enter the lower part of the oil shale dry distillation device (1) and meet low-temperature gas sprayed out from the transverse gas distribution air port and the longitudinal gas distribution air port (1-10) to complete heat exchange, the temperature of the low-temperature gas is increased, residual carbon in the semicoke is consumed, and partial carbon dioxide in the gas is reduced into carbon monoxide, so that the heat value of the gas is increased.