A single-stage rotary kiln processing device for coal upgrading or resource utilization

Abstract

The application discloses a single-stage rotary kiln processing device for coal upgrading or resource utilization, and particularly relates to the field of coal chemical device. The device comprises a raw coal feeding system, a rotary kiln pyrolysis furnace, a jacket heating layer of the rotary kiln outer wall and outer ring kiln, a cooling washing tower, a light oil recovery system, a combustion chamber, a quenching chamber, a semi-coke conveyor, a crude coke tar purification system and an induced draft fan. The raw coal feeding system is sequentially connected with the rotary kiln pyrolysis furnace, the cooling washing tower and the semi-coke conveyor; the cooling washing tower is connected with the combustion chamber through the light oil recovery system; the non-condensable coal gas after water removal is combusted with air in the combustion chamber; the combustion chamber is connected with the quenching chamber, and the quenching chamber is used for quenching the high-temperature gas after combustion as a pyrolysis heat source; the quenching chamber is connected with the jacket heating layer of the rotary kiln outer wall and outer ring kiln, and the high-temperature gas is used for heating the rotary kiln pyrolysis furnace; the gas after heating is discharged through the induced draft fan. The device is more simple than the prior art, easy to operate, stable in performance, and higher in processing efficiency.

Description

Technical Field

[0001] This invention relates to the field of coal chemical equipment, specifically to a single-stage rotary kiln processing device for coal upgrading or resource recovery. Background Technology

[0002] Currently, coal in my country is mainly used for power generation, coking, and industrial and domestic fuel. The fuel and power industries typically require low-sulfur, high-quality coal or specific coal types (such as gas coal, coking coal, and lean coal for coking). Developing clean coal technologies is an important way to improve China's energy efficiency, conserve energy and reduce emissions, achieve clean and low-carbon development, and reduce environmental pollution (including urban smog).

[0003] Although my country has relatively abundant coal resources, only about half are high-quality coal, with the remainder being low-quality coal such as lignite. Young coal types like lignite account for about 40% of my country's coal reserves, reaching over 70% in eastern Inner Mongolia. Due to their high moisture, ash, volatile matter, and low calorific value, young coal types like lignite are often used as low-quality fuel or thermal coal. Furthermore, their susceptibility to decomposition and spontaneous combustion makes them unsuitable for long-distance transportation, thus hindering their processing and utilization in other locations. When high-quality coal is mined, the associated low-quality coal resources cannot be extracted simultaneously due to market factors, remaining permanently underground and resulting in a waste of coal resources.

[0004] The pyrolysis upgrading and oil extraction technology of low-rank coal (such as lignite and long-flame coal) has attracted much attention, and many institutions are conducting research and development. Vertical internal heating pyrolysis furnaces have been industrialized in China, but they are only suitable for lump coal with good thermal stability and are not suitable for lignite and pulverized coal. Therefore, in 2007, the Inner Mongolia Development and Reform Commission organized a seminar on the development and utilization of lignite and other young coal types. Representatives at the seminar suggested adopting lignite pyrolysis technology to process lignite into semi-coke, low-temperature tar, and coke oven gas, thus making full use of the resources. Semi-coke has good stability, meeting the needs of long-distance transportation; its calorific value can reach 4000-5000 kcal / kg, making it suitable as fuel for power generation and industrial furnaces, as well as a feedstock for gasification.

[0005] Currently, the existing technologies for upgrading pyrolytic coal in China using rotary kilns / rotary furnaces or rotary distillation furnaces / rotary distillation mills, such as CN101608126B (a coal pyrolysis upgrading device), CN103074095A (a coal pyrolysis system), CN102732277A (a horizontal rotary segmented return material distillation equipment and process for coal), and CN202220155U (a combined drying and distillation upgrading system for low-rank coal), all combine drying upgrading and pyrolysis upgrading into two units / systems, or even other units.

[0006] Domestic coal pyrolysis processes mostly generate water, including pyrolysis wastewater produced during gas cooling, washing, and tar separation. Low-temperature (400–800℃) coal pyrolysis can rapidly convert coal into coal-based products such as coal gas and tar. Due to the lower reaction temperature and coal quality, the wastewater generated from low-rank coal pyrolysis is more complex than that from traditional coal gasification, containing aromatic and long-chain hydrocarbons, benzene, volatile phenols, ammonia nitrogen, and oils. It is characterized by high COD, high color, and poor biodegradability. Phenolic compounds and nitrogen-containing heterocyclic compounds are predominant, many of which are highly toxic and carcinogenic, making treatment extremely difficult and requiring deep treatment. Furthermore, recycling is challenging, increasing coal pyrolysis production costs and exacerbating the environmental crisis in the coal industry. Clean, efficient treatment and zero discharge of pyrolysis wastewater are urgent problems to be solved. Moreover, my country's coal and water resources are inversely distributed; for coal chemical enterprises in water-scarce areas, water recycling is of great significance.

[0007] Currently, the main clean coal technology being developed in Europe and America is externally heated rotary kilns, which avoid direct contact with coal to prevent oxidation or combustion and chain reactions. In an almost oxygen-free state, the water, impurities, volatile organic matter including polycyclic aromatic hydrocarbons and tar in the coal are thermally cracked and separated to produce high-quality, high-calorific-value, smokeless clean coal (semi-coke) and fuel oil with very low dust content.

[0008] However, most rotary kiln pyrolysis systems currently require frequent shutdowns for cleaning or maintenance due to equipment blockages. Shutdowns necessitate a cooling period, followed by a warm-up period before restarting, resulting in significant productivity reductions. Common points of blockage in existing rotary kiln pyrolysis systems include:

[0009] 1. Solid particles (or those containing tar) accumulate and block the pipes between the pyrolysis reactor and the cooling and washing tower when carried away from the rotary kiln pyrolysis furnace by the pyrolysis gas.

[0010] 2. When pyrolysis gas exits the cooling and scrubbing tower, the oil mist cools and accumulates, clogging the outlet of the scrubbing tower, causing the cooling and scrubbing tower to lose its function and the entire system to fail to operate.

[0011] 3. The bottom outlet of the cooling scrubbing tower is blocked by solid particles containing tar, causing the cooling scrubbing tower to lose its function and the entire system to fail to operate.

[0012] 4. The screw conveyor between the dryer and the rotary kiln pyrolysis furnace is prone to blockage by solid materials. Summary of the Invention

[0013] Therefore, the present invention provides a continuous, high-performance single-stage rotary kiln processing device for coal upgrading or resource utilization, in order to improve the existing pyrolysis raw coal upgrading technology or solve the problem of pyrolysis coal wastewater and solve the problem of easy blockage in existing devices.

[0014] To achieve the above objectives, the present invention provides the following technical solution:

[0015] According to the present invention, a single-stage rotary kiln processing device for coal upgrading or resource utilization includes:

[0016] Raw coal feeding system, rotary kiln pyrolysis furnace, outer wall of rotary kiln and jacket heating layer of outer ring kiln, cooling and washing tower, light oil recovery system, combustion chamber, quenching chamber, semi-coke conveyor, crude tar purification system, induced draft fan;

[0017] The raw coal feeding system is connected to the rotary kiln pyrolysis furnace.

[0018] A cooling and scrubbing tower and a semi-coke conveyor are connected after the rotary kiln pyrolysis furnace. The gas enters the cooling and scrubbing tower, which uses 10W grade machine oil as a coolant to cool the pyrolysis gas and the crude tar it contains. At the same time, the viscous machine oil impacts and removes the condensed crude tar and dust particles from the gas. The semi-coke conveyor is used to cool and recover the semi-coke after the rotary kiln pyrolysis.

[0019] After cooling and scrubbing, the gas passes through a light oil recovery system and is connected to a combustion chamber. The combustion chamber is used for the combustion of the gas after water removal and the gas after the recovery of condensable light oil.

[0020] The combustion chamber is followed by a quenching chamber, which is used to quench the high-temperature gas from the combustion process to provide the heat source for the rotary kiln pyrolysis furnace and the required specific operating temperature range.

[0021] The outer wall of the rotary kiln is connected to the jacket heating layer of the rotary kiln via a quenching chamber, which is used to heat the rotary kiln pyrolysis furnace. The heated gas is then discharged by an induced draft fan.

[0022] A tar purification system with a centrifugal separator is used to forcefully extract the bottom discharge from the cooling washing tower, which contains cooled machine oil, crude tar, fine dust particles, and soot, along with the tar and other organic matter they are attached to. Solid-liquid separation is then performed to separate the recovered oil, including machine oil and tar. The separated fine dust particles, soot, and the tar and organic matter they are attached to are sent back to the rotary kiln pyrolysis furnace for secondary pyrolysis.

[0023] The recovered oil after separation and purification can be sent back to the bottom of the washing tower to replenish the consumed oil. It first flows through the filter to remove solid particles that may clog the nozzles of the cooling washing tower, and then passes through the second heat exchanger to reduce the temperature to about 75°C before being circulated back to the cooling washing tower for use. If the quality of the raw coal is insufficient to recover enough tar to replenish the coolant, then oil (grade 10W) ​​can be added.

[0024] Furthermore, the raw coal feeding system includes a movable bottom bed feeder, a feeding transfer conveyor, and a feeding input conveyor; the three are connected in sequence for feeding raw coal; the feeding input conveyor is connected to the rotary kiln pyrolysis furnace.

[0025] Furthermore, the movable bed feeder has a variable speed drive device and a counterclockwise screw propeller; the feeding conveyor is an inclined cylindrical conveyor with external bearings and a cantilever drive shaft; and the feeding input conveyor is a heavy-duty screw conveyor.

[0026] Furthermore, the rotary kiln consists of a fixed outer ring kiln and an internal rotary kiln. The outer wall of the rotary kiln is densely covered with approximately 20,000 needle-like fins, each about 1.27 cm in diameter and 22.86 cm long, perpendicular to the direction of the hot air flow. Inside the rotary kiln, there is a floating scraper and a small steel ball internal circulation device. The head and tail ends of the rotary kiln each have a feed cover and a discharge cover with a self-lubricating carbon steel sealing device, as well as a uniquely designed tire and drive device. This ensures that the rotary kiln pyrolysis furnace, which is less than 1 meter long, is not located within the jacket layer of the outer ring kiln and the outer wall of the rotary kiln (i.e., within the effective heat transfer area).

[0027] This invention features a novel and unique rotary kiln pyrolysis furnace drive system, with the remainder of the kiln, except for the initial approximately 1m, located within the jacket layer of the outer ring kiln (i.e., within the effective heat transfer area). Traditional rotary kiln designs use approximately 3m or longer of the kiln as the mounting point for the tires and drive gears (i.e., occupying a significant portion of the available heat transfer area). For a 24m long rotary kiln pyrolysis furnace, this invention provides at least 10% more usable heat transfer area compared to traditional designs. In other words, the drive system, i.e., the mounting of the tires and drive gears, is housed with minimal external wall area of ​​the rotary kiln. The remaining area can then be utilized as the effective heat transfer area within the jacket layer.

[0028] The small steel ball circulation system is located at the outlet of the pyrolysis furnace. 100 small steel balls with a diameter of about 5 cm are heated and then returned to the colder raw coal feeding system through this circulation system.

[0029] Furthermore, the cooling scrubbing tower is a direct-flow cooling system that uses machine oil (grade 10W) ​​as the coolant.

[0030] The contact-type condensation scrubbing tower is equipped with two sets of automatically switching demisters at the top to remove oil mist, and two sets of scrubbing solvent filtration systems to clean clogged demisters. When a running demister becomes clogged to a certain degree, it automatically switches to the other standby one. At the same time, the scrubbing solvent filtration system automatically starts to clean the clogged demister until it is completely cleaned and then stops.

[0031] Furthermore, the device also includes a continuous automatic pipeline cleaning device; a closed hydraulic drive, hydraulic tool control valve, and carbon steel telescopic push rod installed on the exhaust gas pipeline between the rotary kiln pyrolysis furnace and the cooling washing tower.

[0032] Furthermore, the device also includes a crude tar purification system connected to the oil storage device, which uses a centrifugal separator to purify the crude tar. The purified tar is then returned to the cooling and washing tower for cooling or recycling and sale.

[0033] Furthermore, the device also includes a light oil recovery system, comprising a first heat exchanger (an externally circulating cooling water, indirect water-cooled horizontal long duct), a water separator, and an oil-water separator, which condenses, removes, and recovers water vapor while simultaneously recovering condensable light oil; the recovered water can be used for subsequent cooling water replenishment. The recovered condensable light oil can be sold.

[0034] Furthermore, the device also includes a second heat exchanger and a filter; the filter and the second heat exchanger are connected after the cooling scrubbing tower; the purified tar treated by the filter and the second heat exchanger is returned to the cooling scrubbing tower for cooling and reuse.

[0035] Furthermore, the device also includes a burner fan connected to the front of the combustion chamber to ensure the combustion of the gas in the combustion chamber.

[0036] Furthermore, the device also includes a floating scraper located inside the rotary kiln pyrolysis furnace, which rotates continuously during system operation to scrape off material adhering to the kiln wall.

[0037] Furthermore, the device also includes a semi-coke conveyor, which mainly utilizes a screed conveyor with an inclined angle within a load-bearing cylindrical mechanism—a load-bearing, circulating, indirect water-cooled semi-coke heat exchanger—to discharge the semi-coke solids. These powdered solids themselves form a barrier during the discharge process, preventing air from entering the system. Moreover, the powdered semi-coke conveyor of this invention is located below the kiln tail hood and has no internal connection or bearings, thus being seamless and using an offset rotary valve to prevent air from entering the system.

[0038] Furthermore, the crude tar purification system powerfully extracts and separates the emissions from the bottom of the cooling and washing tower, which contain cooled engine oil, crude tar, particulate matter, and soot, along with the crude tar and other organic matter adhering to them. This process yields recovered oil, including engine oil and tar. The separated particulate matter, soot, and the tar and organic matter adhering to them are returned to the rotary kiln pyrolysis furnace for secondary pyrolysis. The purified recovered oil can be returned to the bottom of the washing tower to replenish the consumed engine oil as a coolant. It first flows through a filter and then through a second heat exchanger to reduce the temperature to approximately 75°C before being circulated back to the cooling and washing tower. If the raw coal quality is insufficient to recover enough tar to replenish the consumed coolant, engine oil (grade 10W) ​​can be added.

[0039] Furthermore, the device also includes a nitrogen generator and a nitrogen heater, used to flush away and seal the tar adhering to the surface of the feed and discharge mask cover, and to cool the rapidly increasing temperature inside the pyrolysis furnace or to increase the rapidly decreasing temperature through the nitrogen heater, thereby releasing and expelling the sudden increase in oxygen inside the furnace, preventing combustion or even explosion, and improving the quality, calorific value, and crude tar yield of the semi-coke. When it is necessary to cool the rapidly increasing temperature inside the rotary kiln pyrolysis furnace, the nitrogen heater is not turned on, and nitrogen at the ambient temperature is directly generated by the nitrogen generator; when it is necessary to increase the rapidly decreasing temperature inside the pyrolysis furnace, the nitrogen heater is turned on, and the nitrogen generated by the nitrogen generator is first heated by the nitrogen heater.

[0040] The present invention has the following advantages:

[0041] The present invention installs needle-like fins perpendicular to the direction of hot air flow on the outer wall of the rotary kiln pyrolysis furnace within the jacket layer. These fins resemble heat transfer fins and scales in a boiler, which not only enhances the rigidity of the rotary kiln and increases the heat convection and conduction area by about 110% compared to the traditional design, but also increases its heat transfer efficiency by more than three times compared to a bare-faced pyrolysis furnace without scales.

[0042] This invention features a novel and unique rotary kiln pyrolysis furnace drive system, with the remainder of the kiln located within the jacket layer of the outer ring kiln (i.e., within the effective heat transfer area), except for the initial approximately 1m. Traditional rotary kiln designs utilize a kiln approximately 3m or longer as a mounting point for the tires and drive gears (i.e., occupying a significant portion of the available heat transfer area). For a 24m long rotary kiln pyrolysis furnace, this invention provides at least 10% more usable heat transfer area compared to traditional designs.

[0043] This invention's single-stage rotary kiln processing device differs significantly from existing domestic technologies that use rotary kilns / furnaces or rotary distillation furnaces / distillers for pyrolysis coal upgrading. It combines drying and upgrading with two-unit / system approaches, or even other units. This invention's rotary kiln pyrolysis furnace eliminates the need for a separate dryer, enabling a single, integrated, multi-stage, continuous, and high-performance process for drying, pyrolysis, upgrading, and thermal stabilization. This simplifies the process and reduces system operation, maintenance, and related costs. It also avoids the problem of solid material blockage in the screw conveyor between the dryer and the rotary kiln pyrolysis furnace, which often requires frequent shutdowns for cleaning or maintenance, thus preventing a significant reduction in productivity.

[0044] This invention uses engine oil sprayed into a cooling scrubbing tower to cool coal gas. Simultaneously, the viscous engine oil and the recovered, purified tar impact and remove crude tar containing crude gasoline, crude diesel, crude phenols, heavy oil, and dust particles. The tar is then separated and removed by a tar purification system and returned to the rotary kiln for further processing and pyrolysis. Therefore, the pyrolysis process of this invention does not produce coal gas, scrubbing, or tar separation wastewater. The circulating cooling water flowing through the horizontal long conduit of the light oil recovery system of this invention does not come into contact with clean, combustible volatile gases. Essentially, the water usage of this invention is very low, requiring only a small amount for evaporation and emergency firefighting, thus eliminating the need for wastewater treatment. The water separated by the light oil recovery system can be used as replenishment water for the circulating cooling system.

[0045] The production rates of combustible volatile gases and crude tar in the cooling scrubbing tower of this invention can be adjusted by changing the amount of coolant, i.e., the amount of circulating oil, thereby lowering or increasing the operating temperature of the cooling scrubbing tower. For example, lowering the amount of circulating oil will increase the operating temperature of the cooling scrubbing tower, resulting in a slight increase in the production of combustible volatile gases; conversely, lowering the amount of circulating oil will increase the amount of recovered oil. For instance, increasing the amount of circulating oil to lower the inlet oil temperature of the cooling scrubbing tower to 153°C will result in a slightly lower production of combustible volatile gases compared to when the inlet oil temperature is 163°C, but a slightly higher production of crude tar.

[0046] The present invention uses a floating scraper in the pyrolysis furnace, which can scrape off substances such as tar adhering to the inner wall of the kiln during the rotation of the rotary kiln (in order to maintain a high heat transfer rate) and further crush the coal raw material, improve heat transfer efficiency and the output of pyrolysis gas and recovered oil.

[0047] This invention relates to a single-stage rotary kiln processing device for coal upgrading or resource recovery, which features unique sealing devices at both the feed kiln head and the semi-coke discharge kiln tail to prevent air from entering the pyrolysis system and process. The sealing device of this invention has a superior sealing design, ensuring pyrolysis in an oxygen-deficient environment, i.e., with minimal air (<0.3m³). 3 / hour, or approximately 0.355 kg / hour (at 25°C and atmospheric pressure), may seep in through its sealing device. Otherwise, it may cause oxidation or even combustion, as well as CO2 and NO. x The formation of this process results in the loss of the purpose of pyrolysis and the unpredictable production of high-quality semi-coke, oil, and gas.

[0048] The small steel balls in this invention can release and transfer heat to the relatively cold feed. In addition to improving heat transfer efficiency (10% or more), the rolling and impacting of the small steel balls in the kiln can break up the tar, preventing it from sticking to the kiln wall. They can also crush the feed and pyrolysis products, and avoid the problems of sparks or even oxidation that may occur due to tar sticking.

[0049] This invention is equipped with a specially designed feeding and semi-coke discharge device, which can prevent air from entering the pyrolysis system through gaps. In addition, since a heavy-duty, low-speed device is used and there are no bearings or joint connections, the wear of the feeding and semi-coke equipment is greatly reduced, and maintenance costs are therefore very low.

[0050] The present invention uses a continuous automatic pipeline cleaning device, a dual set of demisters that automatically switch operation, and a crude tar purification system to ensure that the pyrolysis system of the present invention can continue to operate continuously and stably without blockage. Attached Figure Description

[0051] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0052] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0053] Figure 1 This is a diagram of a single-stage rotary kiln processing device for coal upgrading or resource utilization provided in Embodiment 1 of the present invention;

[0054] Figure 2 This is a diagram of a single-stage rotary kiln processing device for coal upgrading or resource utilization provided in Embodiment 2 of the present invention;

[0055] Figure 3This is an enlarged view of the interior of a rotary kiln pyrolysis furnace provided in Embodiment 1 of the present invention;

[0056] In the diagram: 1-Raw coal feeding system; 1-1-Modible bed feeder; 1-2-Feed transfer conveyor; 1-3-Feed input conveyor;

[0057] 2-Rotary kiln; 2-1-Rotary kiln pyrolysis furnace; 2-1-1-Rotary kiln pyrolysis furnace feed cover; 2-1-2-Rotary kiln pyrolysis furnace discharge cover; 2-2-Rotary kiln outer wall and rotary kiln jacket heating layer; 2-3-Floating scraper;

[0058] 3-Cooling scrubbing tower; 3-1-Demister;

[0059] 4-Purified tar tank; 5-Crude tar purification system; 6-First heat exchanger; 7-Water separator; 8-Oil-water separator; 8-1 Water tank; 8-2 Light oil tank; 9-Combustion chamber; 9-1 Burner fan; 9-2 Burner;

[0060] 10- Semi-coke conveyor; 11- Sudden cooling chamber; 12- Second heat exchanger; 13- Filter; 14- Semi-coke heat exchanger; 15- Exhaust fan; 16- Continuous automatic pipeline cleaning device; 17- Semi-coke storage device; 18- Oil storage device; 19- Nitrogen generator; 20- Nitrogen heater. Detailed Implementation

[0061] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0062] Example 1

[0063] like Figure 1 As shown, this embodiment provides a single-stage rotary kiln processing device for coal upgrading or resource utilization:

[0064] This invention provides a single-stage rotary kiln processing device for coal upgrading or resource utilization, the device comprising:

[0065] 1. Raw coal feeding system; 2. Rotary kiln; 3. Rotary kiln pyrolysis furnace; 4. Rotary kiln pyrolysis furnace feed cover; 5. Rotary kiln pyrolysis furnace discharge cover; 6. Jacket heating layer between the outer wall of the rotary kiln and the outer ring kiln; 7. Cooling and washing tower; 8. Purified tar oil tank; 9. Crude tar purification system; 10. First heat exchanger; 11. Water separator; 2. Oil-water separator; 12. Water tank; 13. Light oil tank; 14. Combustion chamber; 15. Burner fan; 16. Burner; 17. Burner; 18. Semi-coke conveyor; 19. Rapid cooling chamber; 10. Second heat exchanger; 19. Filter; 10. Semi-coke heat exchanger; 11. Exhaust fan; 12. Continuous automatic pipeline cleaning device; 13. Semi-coke storage device; 14. Oil storage device; 15.

[0066] The rotary kiln 2 includes a rotary kiln pyrolysis furnace 2-1; a rotary kiln pyrolysis furnace feed cover 2-1-1; a rotary kiln pyrolysis furnace discharge cover 2-1-2; and a jacketed heating layer 2-2 and 2-3 between the outer wall of the rotary kiln and the outer ring kiln, and a floating scraper.

[0067] The raw coal feeding system 1 is connected in sequence to the rotary kiln pyrolysis furnace feed cover 2-1-1 and the rotary kiln pyrolysis furnace 2-1; the rotary kiln pyrolysis furnace discharge cover 2-1-2 is located at the outlet of the rotary kiln pyrolysis furnace 2-1;

[0068] After the rotary kiln pyrolysis furnace 2-1, a cooling and washing tower 3 and a semi-coke conveyor 10 are connected respectively. The coal gas enters the cooling and washing tower 3 to cool the pyrolysis coal gas and the crude tar contained therein. The semi-coke conveyor 10 is used to recover the semi-coke after the rotary kiln pyrolysis. The recovered semi-coke is stored in the semi-coke storage device 17.

[0069] The semi-coke conveyor 10 primarily utilizes a axial screw conveyor within a load-bearing, cylindrical, indirect water-cooled semi-coke heat exchanger 14 with an inclined angle to discharge semi-coke solids. These powdered solids themselves form a barrier during discharge, preventing air from entering the system. Furthermore, the powdered semi-coke conveyor 10 of this invention is located below the kiln tail hood and has no internal connections or bearings, thus being seamless and employing an offset rotary valve to prevent air from entering the system.

[0070] After cooling the washing tower 3, the gas is connected to the combustion chamber 9 via the first heat exchanger 6 and the water separator 7; the combustion chamber 9 is used for the combustion of water-depleted gas with added air.

[0071] Combustion chamber 9 is connected to quenching chamber 11, which is used to quench the gas after combustion.

[0072] The outer wall of the rotary kiln is connected to the jacket heating layer of the rotary kiln via a quenching chamber 11, which is used to heat the rotary kiln pyrolysis furnace 2-1. The gas is discharged through the induced draft fan 15 behind it.

[0073] Furthermore, the raw coal feeding system 1 includes a movable bottom bed feeder 1-1, a feeding transfer conveyor 1-2, and a feeding input conveyor 1-3; the three are connected in sequence for feeding raw coal; the feeding input conveyor is connected to the rotary kiln pyrolysis furnace 2-1.

[0074] Furthermore, rotary kiln 2: has a fixed outer ring kiln and an internal rotary kiln pyrolysis furnace 2-1, with a floating wall scraper 2-3 installed inside the rotary kiln pyrolysis furnace 2-1, such as... Figure 3 As shown, the rotary kiln pyrolysis furnace feed cover 2-1-2 and rotary kiln pyrolysis furnace discharge cover 2-1-2, each containing a self-lubricating carbon steel sealing device at both ends of the rotary kiln, as well as the tire and drive device, ensure that the rotary kiln pyrolysis furnace, which is less than 1 meter long, is not within the outer wall of the rotary kiln and the jacket layer of the outer ring kiln (i.e., within the effective heat transfer area).

[0075] The small steel ball circulation system is located at the outlet of the rotary kiln pyrolysis furnace 2-1. 100 small steel balls with a diameter of about 5 cm are heated and then returned to the feed inlet of the colder raw coal feeding system 1 through this circulation system.

[0076] Furthermore, the movable bed feeder 1-1 has a variable speed drive device and a counterclockwise screw propeller; the feed conveyor 1-2 is an inclined cylindrical conveyor with external bearings and a cantilever drive shaft; and the feed input conveyor 1-3 is a heavy-duty screw conveyor.

[0077] Furthermore, the cooling washing tower 3 is a direct contact condensing washing tower that uses machine oil (grade 10W) ​​as a coolant. It is equipped with two sets of automatically switching demisters 3-1 at the top to remove oil mist and two sets of washing solvent filtration systems to clean the demisters 3-1 that are clogged.

[0078] Furthermore, the device also includes a crude tar purification system 5, connected to the tar purification tank 4, which uses a centrifugal separator to purify the crude tar. The purified crude tar is then returned to the cooling washing tower 3 for cooling. Furthermore, the device also includes a water tank 8-1, connected to the recovery water separator 7. The water separated in the recovery water separator 7 is then separated and recovered by an oil-water separator 8 to separate and recover condensable light oil. The water after removing the condensable light oil is used for subsequent cooling water replenishment. Furthermore, the crude tar purification system 5 is used to forcefully extract the emissions from the bottom 3 parts of the cooling and washing tower, including cooled machine oil, crude tar, fine dust particles, and soot, as well as the crude tar and other organic matter adhering to them, and perform solid-liquid separation to separate the recovered oil, including machine oil and tar. The separated fine dust particles and soot, as well as the tar and organic matter adhering to them, are sent back to the rotary kiln pyrolysis furnace 2-1 for secondary pyrolysis. The separated and purified recovered oil can be sent back to the bottom of the washing tower to replenish the consumed machine oil. It first flows through the filter 13 and then through the second heat exchanger 12 to reduce the temperature to about 75°C before being circulated back to the cooling and washing tower for use. If the quality of the raw coal is insufficient to recover enough tar to replenish the consumed coolant, machine oil (grade 10W) ​​can be added.

[0079] Furthermore, the device also includes a continuous automatic pipeline cleaning device 16; a closed hydraulic drive, hydraulic tool control valve, and a carbon steel telescopic push rod installed on the exhaust gas pipeline between the rotary kiln pyrolysis furnace 2-1 and the cooling washing tower 3.

[0080] Furthermore, the device also includes a light oil tank 8-2, which is connected to the solidifiable light oil separated in the oil-water separator 8, and can be recycled and sold.

[0081] Furthermore, the device also includes a second heat exchanger 12 and a filter 13; the filter 13 and the second heat exchanger 12 are connected after the cooling washing tower 3; solid particles that may clog the nozzles of the cooling washing tower are removed by the filter 13 and the tar that has been cooled by the second heat exchanger 12 is returned to the cooling washing tower 3 for cooling.

[0082] Furthermore, the device also includes a burner fan 9-1 and a burner 9-2, connected to the front of the combustion chamber 9, to ensure complete combustion of the gas in the combustion chamber 9.

[0083] Furthermore, the device also includes a floating scraper 2-3, located inside the rotary kiln pyrolysis furnace 2-1, for scraping off materials adhering to the inner wall of the kiln.

[0084] Furthermore, the device also includes a crude tar purification system 5 connected to the oil storage device 18, which uses a centrifugal separator to purify the crude tar. The purified tar is then returned to the cooling and washing tower 3 for cooling or recycling and sale.

[0085] Example 2

[0086] This embodiment provides a single-stage rotary kiln processing device for coal upgrading or resource recovery:

[0087] This device is also equipped with a nitrogen generator 19 and a nitrogen heater 20. The nitrogen generator 19 is connected to the nitrogen heater 20, which is located after the quenching chamber 11. The nitrogen heater 20 is connected to the feed cover of the 2-1-1 rotary kiln pyrolysis furnace and the discharge cover of the 2-1-2 rotary kiln pyrolysis furnace, respectively. It is used to flush and fill the sealing devices at both ends of the kiln and to regulate the temperature inside the pyrolysis furnace, thereby improving the quality of semi-coke, its calorific value, and the yield of crude tar. Everything else is exactly the same as in Example 1.

[0088] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A single-stage rotary kiln processing device for coal upgrading or resource utilization, characterized in that, The device includes: Raw coal feeding system, rotary kiln pyrolysis furnace, jacket heating layer between the outer wall of the rotary kiln and the outer ring kiln, cooling and washing tower, light oil recovery system, combustion chamber, quenching chamber, semi-coke conveyor, crude tar purification system, induced draft fan; The raw coal feeding system is connected to the rotary kiln pyrolysis furnace; the rotary kiln pyrolysis furnace is connected to a cooling and washing tower and a semi-coke conveyor; the coal gas enters the cooling and washing tower, which uses 10W grade machine oil as a coolant to cool the pyrolysis coal gas and the crude tar it contains; the semi-coke conveyor is used to cool and recover the semi-coke after the rotary kiln pyrolysis. After cooling and scrubbing, the gas passes through a light oil recovery system and is connected to a combustion chamber. The combustion chamber is used for the combustion of the gas after water removal and the gas after the recovery of condensable light oil. The combustion chamber is followed by the quenching chamber, which is used to quench the high-temperature gas after combustion in order to provide the heat source for the rotary kiln pyrolysis furnace and the required specific operating temperature range. The outer wall of the rotary kiln is connected to the jacket heating layer of the rotary kiln, which is a quenching chamber used to heat the rotary kiln pyrolysis furnace. The heated gas is discharged through the induced draft fan behind it. The crude tar purification system uses a centrifugal separator to purify crude tar, and the purified tar is then returned to the cooling and washing tower for cooling. The device also includes a continuous automatic pipeline cleaning device; a closed hydraulic drive, hydraulic tool control valve, and carbon steel telescopic push rod installed on the exhaust gas pipeline between the rotary kiln pyrolysis furnace and the cooling washing tower.

2. The single-stage rotary kiln processing device for coal upgrading or resource utilization according to claim 1, characterized in that, The raw coal feeding system includes a movable bottom bed feeder, a feeding transfer conveyor, and a feeding input conveyor; the three are connected in sequence for feeding raw coal; the feeding input conveyor is connected to the rotary kiln pyrolysis furnace.

3. The single-stage rotary kiln processing device for coal upgrading or resource utilization according to claim 2, characterized in that, The movable bed feeder has a variable speed drive device and a counterclockwise screw propeller; the feed conveyor is an inclined cylindrical conveyor with external bearings and a cantilever drive shaft; the feed input conveyor is a heavy-duty screw conveyor.

4. A single-stage rotary kiln processing device for coal upgrading or resource utilization according to claim 3, characterized in that: The rotary kiln processing device consists of a fixed outer ring kiln and an internal rotary kiln. The rotary kiln is equipped with a floating scraper and a small steel ball internal circulation device. The head and tail ends of the rotary kiln each have a feed cover and a discharge cover with a self-lubricating carbon steel sealing device, as well as a tire and a drive device.

5. The single-stage rotary kiln processing device for coal upgrading or resource utilization according to claim 4, characterized in that, The cooling and washing tower uses 10W machine oil as a coolant. It is a direct contact condensation washing tower with two sets of automatically switching demisters and two sets of washing solvent filtration systems installed at the top.

6. The single-stage rotary kiln processing device for coal upgrading or resource utilization according to claim 5, characterized in that, The device also includes a light oil recovery system, comprising a first heat exchanger, a water separator, and an oil-water separator, which are connected to a horizontal long duct for external circulation of cooling water; the system condenses, removes, and recovers water vapor, while simultaneously recovering condensable light oil; the recovered water is used for subsequent cooling water replenishment.

7. The single-stage rotary kiln processing device for coal upgrading or resource utilization according to claim 6, characterized in that, The device also includes a second heat exchanger and a filter; the filter and the second heat exchanger are connected after the cooling scrubbing tower; the purified tar after being treated by the filter and the second heat exchanger is sent back to the cooling scrubbing tower for cooling and reuse.

8. The single-stage rotary kiln processing device for coal upgrading or resource utilization according to claim 7, characterized in that, The device also includes a nitrogen generator and a nitrogen heater, used to flush and fill the seal of the feed and discharge mask cover, and to cool the rapidly increasing temperature in the pyrolysis furnace or to increase the rapidly decreasing temperature through the nitrogen heater, thereby releasing and expelling the sudden increase in oxygen in the furnace, preventing combustion or even explosion, and improving the quality of semi-coke, calorific value and crude tar yield.

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