An external heat vertical continuous coal pyrolysis-gasification device and cogeneration system

Abstract

The present disclosure provides an external heating vertical coal pyrolysis-gasification integrated device and a poly-generation system, comprising: a furnace body, the upper part of the furnace body defines a pyrolysis section, the inside of the pyrolysis section is provided with a plurality of pyrolysis cavities suitable for accommodating raw coal pyrolysis, the lower part of the furnace body defines a gasification section, the inside of the gasification section is provided with a gasification cavity suitable for accommodating the pyrolysis of coal and the gasification of the gasification agent, and the pyrolysis cavity and the gasification cavity are both configured as an indirect heating external heating structure; wherein the pyrolysis cavity is provided with a first exhaust port suitable for discharging pyrolysis gas, and the gasification cavity is provided with a second exhaust port suitable for discharging gasification gas. Coal pyrolysis and coal char gasification are coupled and integrated in a set of devices, the irreversible loss of the pyrolysis-gasification process is reduced from the system, and the comprehensive cascade utilization of system energy is realized.

Description

Technical Field

[0001] At least one embodiment of this disclosure relates to the field of coal pyrolysis and gasification technology, and more specifically, to an externally heated vertical continuous pyrolysis-gasification device and co-production system. Background Technology

[0002] Low-rank coal is characterized by low coalification degree, high volatile matter content, and an oil content exceeding 10%. Coal pyrolysis technology is currently the main approach for the clean and efficient utilization of low-rank coal. Through graded and quality-based utilization of coal, clean and high-quality coke, hydrogen-rich pyrolysis gas, and high-value-added coal tar products can be obtained. Traditional coal pyrolysis processes typically employ internally heated pyrolysis furnaces, resulting in relatively low energy utilization. The pyrolysis coke product, which accounts for nearly 70% of the total mass, is usually recovered through external dry or wet quenching methods, leading to significant sensible heat loss from the coke and insufficient utilization. Furthermore, during the mechanical discharge process, wear and tear generates a large amount of fine coke, which is difficult to transport and utilize, resulting in resource waste.

[0003] Coal gasification is another typical clean coal technology, which converts solid coal into syngas fuel in a gasifier using a gasifying agent and high-temperature conditions. Currently, gasifiers use pure oxygen and steam as gasifying agents, requiring large-scale air separation units, which consume a lot of energy. In addition, gasifiers use a "one-pot" gasification method with reaction temperatures exceeding 1200℃, resulting in significant irreversible losses and low system efficiency. Furthermore, using steam as a gasifying agent dilutes the carbon components during gasification, making it difficult to flexibly adjust the CO / H2 carbon-hydrogen ratio required downstream.

[0004] For a long time, traditional coal pyrolysis and gasification plants have been developed independently.

[0005] Based on the respective advantages of coal pyrolysis and gasification technologies, an integrated coal pyrolysis and gasification unit is designed to carry out a multi-product system that couples coal pyrolysis with coal coke gasification. This system enables graded and upgraded utilization of coal and cascaded energy utilization. The high-temperature sensible heat of coal coke is complementarily utilized in the pyrolysis and gasification processes, improving thermal efficiency, reducing heat loss, and increasing the utilization rate of coal coke resources. Using CO2 as a gasifying agent, three product gases—hydrogen-rich coal pyrolysis gas, high-purity H2, and high-purity CO—are obtained separately, and the hydrogen-to-carbon ratio can be flexibly adjusted. Summary of the Invention

[0006] To address at least one of the aforementioned and other technical problems in the prior art, this disclosure provides an externally heated vertical coal pyrolysis-gasification device and co-production system. The pyrolysis chamber and gasification chamber in the furnace body are both constructed as indirectly heated externally heated structures and are interconnected. Through separate gas collection methods, the gasified coal gas produced by gasification does not pass through the pyrolysis chamber, thus allowing the hydrogen-rich pyrolysis gas produced by air-isolated pyrolysis and the gasified coal gas produced by gasification to be discharged separately. This simultaneously yields hydrogen-rich pyrolysis gas, hydrogen, and carbon monoxide, meeting the requirements for flexible adjustment of the downstream hydrogen-carbon ratio. The staged gasification method reduces irreversible losses in the system, improves gasification energy efficiency, and achieves comprehensive cascade utilization of energy.

[0007] One aspect of the embodiments of this disclosure provides an externally heated vertical coal pyrolysis-gasification device, comprising: a furnace body, an upper part of which defines a pyrolysis section, the interior of which is provided with a plurality of pyrolysis chambers suitable for containing raw coal for pyrolysis, a lower part of which defines a gasification section, the interior of which is provided with a gasification chamber suitable for containing pyrolyzed coke and gasifying agent for gasification, wherein the pyrolysis chambers and the gasification chambers are both configured as indirectly heated external heating structures; wherein the pyrolysis chambers are provided with a first exhaust port suitable for discharging pyrolysis gas, and the gasification chambers are provided with a second exhaust port suitable for discharging gasified coal gas.

[0008] According to an embodiment of the present disclosure, the gasification section is provided with an inner furnace wall extending in a vertical direction. The interior of the inner furnace wall defines the gasification chamber. A flue is defined between the exterior of the inner furnace wall and the outer furnace wall of the furnace body. The flue is suitable for accommodating the passage of flue gas used as a heat source and indirectly heating the coal coke in the gasification chamber.

[0009] According to an embodiment of the present disclosure, the interior of the inner furnace wall is provided with a plurality of tubular components, which are arranged at intervals in the vertical direction and extend in the horizontal direction. Each of the tubular components penetrates the opposite sides of the inner furnace wall to communicate with the flue and guide the flue gas through the interior of the gasification chamber.

[0010] According to embodiments of this disclosure, the externally heated vertical continuous pyrolysis-gasification apparatus further includes multiple pairs of burners, with two burners in each pair symmetrically arranged at both ends of the axial direction of one of the aforementioned tubular components. In the orthographic projection in the vertical direction, the combustion position of the burners at least partially coincides with the gasification chamber.

[0011] According to an embodiment of this disclosure, the pyrolysis section is provided with a plurality of pyrolysis chambers at intervals; wherein, the upper part of each pyrolysis chamber is provided with an inlet suitable for inputting the raw coal, and the lower part of each pyrolysis chamber is connected to the upper part of the gasification chamber.

[0012] According to an embodiment of this disclosure, the flue formed in the gasification section is further configured to communicate with the shell side of the pyrolysis section outside the pyrolysis chamber, so that the flue gas passing through the gasification section is also used as a heat source for the pyrolysis section.

[0013] According to embodiments of this disclosure, the externally heated vertical continuous pyrolysis-gasification device further includes a grate, which is rotatably disposed at the lower part of the gasification chamber and is suitable for receiving the ash and slag after gasification. The outer edge of the grate and the inner wall of the gasification chamber form the discharge end of the gasification chamber.

[0014] According to an embodiment of the present disclosure, the gasification section is provided with a gasifying agent inlet suitable for introducing a gasifying agent into the gasification chamber; wherein the gasifying agent inlet is arranged below the grate.

[0015] According to an embodiment of the present disclosure, a transition section connecting the pyrolysis section and the gasification section is formed between the pyrolysis section and the gasification section, and the second exhaust port is disposed in the transition section.

[0016] Another aspect of the embodiments of this disclosure provides a cogeneration system, comprising: an externally heated vertical continuous pyrolysis-gasification device, wherein the pyrolysis section of the externally heated vertical continuous pyrolysis-gasification device is adapted to output hydrogen-rich pyrolysis gas, and the gasification section of the externally heated vertical continuous pyrolysis-gasification device is adapted to output gasified coal gas containing carbon monoxide; and a gasified coal gas treatment device, connected to the gasification section, adapted to accommodate the gasified coal gas and supply steam to produce hydrogen through at least a portion of the carbon monoxide in the gasified coal gas.

[0017] According to embodiments of this disclosure, the gasified coal gas treatment equipment includes: a shift and separator defining a reaction chamber suitable for containing the gasified coal gas and water vapor to undergo a shift reaction to produce hydrogen and separate carbon dioxide; a carbon dioxide storage tank connected to the shift and separator for collecting carbon dioxide; and a carbon dioxide preheater disposed between the carbon dioxide storage tank and the gasification section of the vertical pyrolysis equipment, configured with a hot side suitable for containing the gasified coal gas and a cold side suitable for containing the carbon dioxide, so as to exchange heat between the gasified coal gas and the carbon dioxide, and supply the carbon dioxide as a gasifying agent to the gasification section.

[0018] According to embodiments of this disclosure, the cogeneration system further includes a pyrolysis gas treatment device connected to the pyrolysis gas exhaust port of the pyrolysis section, which is suitable for separating at least a portion of the coal tar from the pyrolysis gas.

[0019] According to embodiments of this disclosure, the cogeneration system further includes a raw coal input device, located upstream of the feed inlet of the aforementioned externally heated vertical pyrolysis-gasification unit, suitable for storing and inputting raw coal to be pyrolyzed into the aforementioned externally heated vertical pyrolysis-gasification unit.

[0020] According to the externally heated vertical pyrolysis-gasification device and co-production system provided in this disclosure, both the pyrolysis chamber and the gasification chamber in the furnace body are constructed as indirectly heated external heating structures. This allows the raw coal to be fully pyrolyzed in the pyrolysis chamber under air-isolated conditions, producing hydrogen-rich pyrolysis gas. Furthermore, since the gasified coal gas produced by gasification does not pass through the pyrolysis chamber, it can be collected simultaneously and processed again to obtain hydrogen-rich pyrolysis gas, hydrogen, and carbon monoxide, respectively, to meet the requirements for flexible adjustment of the downstream hydrogen-carbon ratio. Moreover, due to the use of externally heated pyrolysis and gasification methods, the dust generated during pyrolysis can be reduced, thereby reducing dust in the subsequently extracted coal tar. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of an externally heated vertical pyrolysis-gasification apparatus according to an illustrative embodiment of the present disclosure;

[0022] Figure 2 yes Figure 1 A schematic diagram of the gasification section of an externally heated vertical pyrolysis-gasification apparatus, as shown in the example embodiment;

[0023] Figure 3 yes Figure 1 A schematic diagram, from a top view, of the pyrolysis section of an externally heated vertical pyrolysis-gasification apparatus of an exemplary embodiment; and

[0024] Figure 4 This is a schematic diagram of a combined production system according to an illustrative embodiment of the present disclosure.

[0025] In the accompanying drawings, the meanings of the reference numerals are as follows:

[0026] 1. Furnace body;

[0027] 101. Feed inlet;

[0028] 102. Pyrolysis section;

[0029] 103. Pyrolysis section flue gas inlet;

[0030] 104. Transition section;

[0031] 105. Gasification section;

[0032] 106. Furnace grate;

[0033] 107. Gasifying agent inlet;

[0034] 108. Slag discharge port;

[0035] 109. Ash hopper lock;

[0036] 110. Burner;

[0037] 111. Inner furnace wall;

[0038] 112. Gasification section flue gas outlet;

[0039] 113. Second exhaust port;

[0040] 114. Pyrolysis chamber;

[0041] 115. Hot air chamber;

[0042] 116. Pyrolysis section flue gas outlet;

[0043] 117. Tubular components;

[0044] 2. Raw coal input equipment;

[0045] 21. Dryer;

[0046] 22. Coal hopper lock;

[0047] 3. Waste heat boiler;

[0048] 4. Gasification gas treatment equipment;

[0049] 41. Converter and separator;

[0050] 42. Carbon dioxide preheater;

[0051] 43. Carbon dioxide storage tank;

[0052] 5. Pyrolysis gas treatment equipment;

[0053] 51. Electrostatic precipitator for coal tar; and

[0054] 52. Indirect cooler. Detailed Implementation

[0055] To make the objectives, technical solutions and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0056] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0057] All terms used herein, including technical and scientific terms, have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0058] When using expressions such as "at least one of A, B, and C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C. Similarly, when using expressions such as "at least one of A, B, or C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C.

[0059] Currently, fixed-bed coal gasifiers involve coal drying, pyrolysis, and gasification steps from top to bottom. However, because these steps occur within the same gasifier, the resulting mixed fuel gas consists of pyrolysis gas and gasification gas, making it difficult to adjust the hydrogen-to-carbon ratio of the pyrolysis and gasification products. Furthermore, the internally heated pyrolysis method used in these gasifiers leads to a large amount of dust entrained in the pyrolysis gas, which is difficult to effectively remove from the subsequently produced coal tar.

[0060] Therefore, how to provide a pyrolysis device that can collect gasified coal gas and pyrolysis gas separately and reduce dust and wastewater emissions has become an urgent technical problem to be solved.

[0061] In view of this, embodiments of the present disclosure provide an externally heated vertical pyrolysis-gasification apparatus and co-production system based on the same inventive concept.

[0062] Figure 1 This is a schematic diagram of an externally heated vertical pyrolysis-gasification apparatus according to an illustrative embodiment of the present disclosure.

[0063] According to the externally heated vertical pyrolysis-gasification apparatus provided in this disclosure, such as Figure 1 As shown, the furnace includes a furnace body 1, with an upper portion defining a pyrolysis section 102. The pyrolysis section 102 contains multiple pyrolysis chambers 114 suitable for containing raw coal during pyrolysis. The lower portion of the furnace body 1 defines a gasification section 105, with an internal gasification chamber suitable for containing pyrolyzed coal char and gasifying agent during gasification. Both the pyrolysis chambers 114 and the gasification chambers are constructed as indirect heating external heating structures. The pyrolysis chambers 114 are equipped with a first exhaust port for discharging pyrolysis gas, and the gasification chambers are equipped with a second exhaust port 113 for discharging gasified coal gas.

[0064] In this implementation, by coupling the gasification section 105 and the pyrolysis section 102 in the same furnace body 1, the traditional one-step gasification method can be decoupled into mild pyrolysis and coal coke-carbon dioxide gasification, which helps to reduce irreversible losses in the gasification process and improve gasification energy efficiency.

[0065] According to embodiments of this disclosure, such as Figure 1 As shown, a transition section 104 is formed between the pyrolysis section 102 and the gasification section 105, connecting the pyrolysis chamber 114 and the gasification chamber, and the second exhaust port 113 is disposed in the transition section 104.

[0066] In one illustrative embodiment, such as Figure 1 As shown, the pyrolysis section 102 of the furnace body 1 is formed by refractory bricks and insulating castable, and is equipped with a steel shell on its exterior. Furthermore, the diameter of the transition section 104 between the pyrolysis section 102 and the gasification section 105 is constructed to be smaller than that of the pyrolysis section 102 and the gasification section 105, and is supported by a steel structure.

[0067] In one illustrative embodiment, such as Figure 1 As shown, the furnace body 1 is, but is not limited to, being constructed as a cylindrical or cubic structure. Furthermore, the pyrolysis section 102, the transition section 104, and the gasification section 105 are constructed along... Figure 1 The vertically connected arrangement is shown.

[0068] In this implementation method, the raw coal is gradually consumed during pyrolysis to form coke. The coke moves downward, accumulates and is buffered in the transition section, and gradually enters the gasification section to form a pyrolysis mode similar to static pyrolysis, which helps to prevent the generation of large amounts of dust.

[0069] In one illustrative embodiment, such as Figure 1 As shown, multiple pyrolysis chambers 114 are arranged at horizontal intervals within the pyrolysis section 102. Specifically, a hot air chamber 115 suitable for introducing a heat source is formed between two adjacent pyrolysis chambers 114 and between the pyrolysis chamber 114 and the adjacent inner wall of the furnace body. Furthermore, the hot air chamber 115 is constructed to form an "S"-shaped and a "Z"-shaped flow channel from bottom to top.

[0070] In this embodiment, both the pyrolysis chamber 114 and the gasification chamber in the furnace body 1 are constructed as indirect heating external heating structures, thereby allowing the raw coal to be fully pyrolyzed in the pyrolysis chamber 114 under air-isolated conditions to produce hydrogen-rich pyrolysis gas. Furthermore, since the gasified coal gas produced by gasification does not pass through the pyrolysis chamber 114, it can be collected simultaneously for further processing to obtain hydrogen-rich pyrolysis gas, hydrogen, and carbon monoxide separately. This ensures that the pyrolysis gas, mainly composed of hydrogen and methane, and the gasified coal gas, mainly composed of carbon monoxide, do not interfere with each other, allowing for the separate utilization of products of different grades and meeting the requirements for flexible adjustment of the downstream hydrogen-carbon ratio. Moreover, due to the use of external heating for pyrolysis and gasification, the dust generated during the pyrolysis process can be reduced, thereby reducing dust in the subsequently extracted coal tar.

[0071] Figure 2 yes Figure 1 A schematic diagram of the gasification section of an externally heated vertical pyrolysis-gasification apparatus, as shown in the example embodiment.

[0072] According to embodiments of this disclosure, such as Figure 1 and Figure 2 As shown, the gasification section 105 is provided with an inner furnace wall 111 extending vertically inside. The interior of the inner furnace wall 111 defines a gasification chamber, and the exterior of the inner furnace wall 111 and the outer furnace wall define a flue, which is suitable for accommodating the passage of flue gas used as a heat source, so as to indirectly heat the coal coke in the gasification chamber.

[0073] In one illustrative embodiment, such as Figure 1 As shown, the gasification section 105 of the furnace body 1 is constructed, including but not limited to, through an inner furnace wall 111 and an outer furnace wall. Specifically, the outer furnace wall is constructed of refractory bricks and insulating castable, while the inner furnace wall 111 is constructed of refractory and heat-conducting materials. A ring-shaped flue is formed between the inner furnace wall 111 and the outer furnace wall.

[0074] According to embodiments of this disclosure, such as Figure 1 and Figure 2 As shown, the inner furnace wall 111 is provided with a plurality of tubular components 117. The plurality of tubular components 117 are arranged at intervals in the vertical direction and extend in the horizontal direction. Each tubular component 117 penetrates the two opposite sides of the inner furnace wall 111 to communicate with the flue and guide the flue gas through the interior of the gasification chamber.

[0075] According to embodiments of this disclosure, such as Figure 1 and Figure 2 As shown, the externally heated vertical pyrolysis-gasification device also includes multiple pairs of burners 110. Two burners 110 in each pair are symmetrically arranged at both ends of the axial direction of a tubular component 117. In the vertical orthographic projection, the combustion position of the burner 110 at least partially coincides with the gasification chamber.

[0076] In one illustrative embodiment, such as Figure 1 and Figure 2 As shown, the furnace body 1 includes, but is not limited to, a structure configured as a generally cubic shape. Furthermore, the inner furnace wall 111 is configured as a square tube structure in response to the shape of the furnace body 1, the interior of the inner furnace wall 111 defines a gasification chamber, and the space between the inner furnace wall 111 and the inner wall of the furnace body 1 forms a flue.

[0077] In one illustrative embodiment, such as Figure 1 and Figure 2 As shown, along the coal and coke conveying direction on the inner furnace wall 111 (e.g.) Figure 1 As shown, multiple tubular components 117 are arranged at intervals from top to bottom. Specifically, the multiple tubular components 117 are spaced apart along the height direction, wherein the tubular components 117 penetrate the inner furnace wall 111 and connect to the flue. Furthermore, multiple tubular components 117 are arranged side-by-side at the same vertical height on the inner furnace wall 111.

[0078] In one illustrative embodiment, not shown in the figure, the tubular components 117 at different heights of the inner furnace wall 111 can be configured to be staggered (e.g., some of the tubular components 117 are arranged along...). Figure 1 The arrangement is shown in the left-right direction, and another part of the tubular component 117 is arranged along the left-right direction as shown. Figure 1 The arrangement of the facing directions allows the flue gas in the flue to pass through the gasification chamber formed by the inner furnace wall 111 in different directions, so that the coal and coke located at different positions in the gasification chamber are heated evenly and local low temperature zones are avoided.

[0079] In one illustrative embodiment, such as Figure 1 and Figure 2 As shown, each tubular component 117 has a pair of oppositely arranged burners 110 at both ends. Specifically, each burner 110 is connected to the inner wall of the furnace body 1. Furthermore, the combustion flame of each burner 110 is injected into the tubular component 117, giving the tubular component 117 the function of a furnace. The flue gas generated during combustion is also discharged from the tubular component 117 into a flue and conveyed upwards, thereby stably and uniformly heating the coal and coke. The tubular component 117 may be made of, but is not limited to, heat-resistant steel.

[0080] In one illustrative embodiment, the burners 110 are arranged in multiple layers along the vertical direction, with two or more arranged side by side in the horizontal direction. In this way, the arrangement of multiple burners 110 facing and connected to heat-resistant pipes (i.e., tubular components 117) ensures that heat is evenly distributed within the device, and that heat is transferred both internally and externally simultaneously, thereby enhancing the radiative heat transfer effect and ensuring that the furnace temperature is stable, which can exceed 950°C.

[0081] In one illustrative embodiment, the burner includes, but is not limited to, the combustion of low-rank coal and / or biomass fuels under air conditions to produce high-temperature flue gas. This can replace the current pure oxygen combustion method, eliminating the need for air separation equipment to produce oxygen and avoiding the high-grade power consumption of air separation equipment.

[0082] In this embodiment, the gasification section 105, through the inner furnace wall 111, the tubular component 117, and the inner wall of the furnace body 1, allows the coal and coke passing through the gasification section 105 to be... Figure 1 The two sides shown and the interior of the gasification chamber 105 are provided with heat through heat conduction and heat radiation, respectively. In this way, the flame of the burner 110 is injected into the heat-resistant pipe (i.e., the tubular component 117). The heat-resistant pipe (i.e., the tubular component 117) not only replaces the furnace, but also radiates the heat of the high-temperature flue gas into the furnace through the pipe wall of the tubular component 117. The high-temperature flue gas generated by the burner 110 diffuses from the tubular component 117 into the space between the inner and outer walls. The heat of the high-temperature flue gas in the space is transferred to the interior of the gasification section 105 through the inner wall. The gasification section 105 provides heat from the inner wall from the outside to the inside and from the pipe wall of the tubular component 117 from the inside to the outside through heat conduction and radiation. This increases the heat transfer area, improves the heat supply per unit time, and reduces the distance between the coal and coke in the furnace and the heat source, ensuring the radiation intensity of the heat source and enabling timely and stable heating for the coal and coke and CO2 gasification process.

[0083] According to embodiments of this disclosure, such as Figure 1 As shown, the externally heated vertical pyrolysis-gasification device also includes a grate 106, which is rotatably disposed at the lower part of the gasification chamber and is suitable for receiving the ash and slag after gasification. The outer edge of the grate 106 and the inner wall of the gasification chamber form the discharge end of the gasification chamber.

[0084] According to embodiments of this disclosure, such as Figure 1 As shown, the gasification section 105 is provided with a gasifying agent inlet 107 for introducing gasifying agent into the gasification chamber. The gasifying agent inlet 107 is located below the grate 106.

[0085] In one illustrative embodiment, a rotatable grate 106 is mounted on the lower part of the gasification section 105 via a suspended support mechanism (not shown in the figure). Furthermore, the grate 106 is equipped with a drive unit (not shown in the figure) suitable for driving the grate 106 to rotate about a fixed axis. The rotational speed of the grate 106 can be adjusted by the drive unit to regulate the ash discharge speed. The unit feed rate of raw coal is balanced with the unit coke gasification consumption.

[0086] In one illustrative embodiment, such as Figure 1As shown, the gasifying agent inlet 107 is connected to the grate 106. In detail, a channel for transmitting the gasifying agent is formed inside the grate 106, and multiple through holes connected to the channel are formed on the outside of the grate 106, so that the gasifying agent is evenly distributed into the gasification chamber along the through holes formed in the grate 106.

[0087] In this embodiment, the rotating grate 106 is suitable for receiving the gasified ash and slag. The gasifying agent entering the gasification chamber through the grate 106 is input in the opposite direction to the ash and slag discharge direction, forming a reverse contact heat exchange. In this way, the temperature of the ash and slag is reduced, and the gasifying agent (including but not limited to carbon dioxide and CO2) can be preheated to the reaction temperature.

[0088] In one illustrative embodiment, such as Figure 1 As shown, the lower part of the furnace body 1 is also equipped with an ash hopper 109. Furthermore, the lower end of the ash hopper 109 is provided with a slag discharge port 108, which is used as the discharge end of the externally heated vertical pyrolysis-gasification device.

[0089] Figure 3 yes Figure 1 A schematic diagram of the pyrolysis section of an externally heated vertical pyrolysis-gasification apparatus, as shown in the example embodiment.

[0090] According to embodiments of this disclosure, such as Figure 1 and Figure 3 As shown, the pyrolysis section 102 is internally equipped with multiple pyrolysis chambers 114 at intervals. Each pyrolysis chamber 114 has an inlet 101 at its upper part for feeding raw coal, and the lower part of each pyrolysis chamber 114 is connected to the upper part of the gasification chamber.

[0091] In this implementation, by setting the pyrolysis section 102 into multiple pyrolysis chambers 114, the heat transfer radius can be reduced and the lateral temperature gradient can be lowered compared to the integral pyrolysis section 102, ensuring that the raw coal in the pyrolysis chamber can be fully pyrolyzed.

[0092] According to embodiments of this disclosure, such as Figure 1 and Figure 3 As shown, the flue formed in the gasification section 105 is also configured to communicate with the shell side of the pyrolysis section 102 outside the pyrolysis chamber 114, so that the flue gas passing through the gasification section 105 can also be used as a heat source for the pyrolysis section 102.

[0093] In an illustrative implementation, such as Figure 3 As shown, the pyrolysis section 102 is provided with a plurality of pyrolysis chambers 114 arranged in a staggered manner along the horizontal direction. Furthermore, each pyrolysis chamber 114 is provided with an inlet 101 for feeding raw coal and a pyrolysis gas outlet for discharging pyrolysis gas at its upper part.

[0094] In one illustrative embodiment, such as Figure 1 As shown, a gasification section flue gas outlet is provided at the upper part of the gasification section 105, and correspondingly, a pyrolysis section flue gas inlet 103 is provided at the lower part of the pyrolysis section 102. Specifically, the gasification section flue gas outlet and the pyrolysis section flue gas inlet 103 are connected. Further, a pyrolysis section flue gas outlet 116 is provided at the upper part of the pyrolysis section 102.

[0095] In this embodiment, the S-shaped hot air chamber 115 formed within the pyrolysis section 102 and the staggered pyrolysis chambers 114 are positioned in the direction of raw coal transport (e.g., ...). Figure 1 The vertical direction shown and the arrangement direction input from the feed inlet 101 form a stepped temperature difference to perform stepped heat exchange on the raw coal and extend the heating time, so that the raw coal entering the pyrolysis section 102 is gradually heated from preheating to the pyrolysis temperature. This allows the raw coal to form a near-static pyrolysis mode during the pyrolysis process, thus further avoiding the generation of dust during pyrolysis.

[0096] Figure 4 This is a schematic diagram of a combined production system according to an illustrative embodiment of the present disclosure.

[0097] According to the cogeneration system provided in this disclosure, such as Figure 4 As shown, the system includes an externally heated vertical pyrolysis-gasification unit and a gasification gas treatment device 4. The pyrolysis section 102 of the externally heated vertical pyrolysis-gasification unit is suitable for outputting hydrogen-rich pyrolysis gas, and the gasification section 105 is suitable for outputting gasified gas containing carbon monoxide. The gasification gas treatment device 4 is connected to the gasification section 105 and is suitable for receiving the gasified gas and supplying steam to produce hydrogen from at least a portion of the carbon monoxide in the gasified gas. The entire system utilizes gradient heat, generates no wastewater, has a high degree of environmental friendliness, and reduces investment in the construction of slag and water treatment units.

[0098] In this implementation, the pyrolyzed raw coal gradually moves downwards as the gasification section consumes the coke, and accumulates in the transition section. The high-temperature coke continues downwards into the gasification section, where it comes into counter-current contact with carbon dioxide flowing upwards through the grate under the high temperature (e.g., above 950°C), resulting in a gasification reaction that generates carbon monoxide. The concentration of carbon dioxide gradually decreases as it flows upwards, while the concentration of carbon monoxide increases accordingly until the carbon dioxide is completely reacted. The molar ratio of carbon dioxide to carbon in the coke is, but is not limited to, any value from 1 to 3. The carbon monoxide extracted from the gasification section reaches a temperature of 600°C to 900°C before entering the carbon dioxide heat exchanger, thereby indirectly preheating the gasifying agent (i.e., carbon dioxide) and reducing the energy burden of external fuel combustion in the gasification section.

[0099] According to embodiments of this disclosure, such as Figure 4 As shown, the gasification gas treatment equipment 4 includes a shift converter and separator 41, a carbon dioxide storage tank 43, and a carbon dioxide preheater 42. The shift converter and separator 41 defines a reaction chamber suitable for containing gasified coal gas and water vapor to undergo a shift reaction to produce hydrogen and separate carbon dioxide. The carbon dioxide storage tank 43 is connected to the shift converter and separator 41 and is suitable for collecting carbon dioxide. The carbon dioxide preheater 42 is located between the carbon dioxide storage tank 43 and the gasification section 105 of the externally heated vertical pyrolysis-gasification device. It is equipped with a hot side suitable for accommodating the gasified coal gas and a cold side suitable for accommodating the carbon dioxide, so that the gasified coal gas and carbon dioxide exchange heat, and the carbon dioxide is supplied as a gasifying agent to the gasification section 105.

[0100] In one illustrative embodiment, such as Figure 4 As shown, carbon dioxide storage tank 43 pre-stores carbon dioxide. This storage tank 43 is connected to the gasifying agent inlet 107 of the externally heated vertical pyrolysis-gasification device to supply carbon dioxide as a gasifying agent into the gasification chamber. Furthermore, the second exhaust port 113 of the externally heated vertical pyrolysis-gasification device is connected to a carbon dioxide preheater 42 to preheat the carbon dioxide with the gasified coal gas passing through the preheater 42. Further, the heat-exchanged gasified coal gas mixes with the input steam in the reaction chamber of the shift and separator 41 to form hydrogen and carbon dioxide. The carbon dioxide separated by the shift and separator 41 flows back to the carbon dioxide storage tank 43 for storage or is returned to the gasification chamber of the externally heated vertical pyrolysis-gasification device via the carbon dioxide preheater 42.

[0101] In this implementation, pure carbon dioxide is used as the gasifying agent to react with high-temperature coal char, generating gasified coal gas with a high concentration of carbon monoxide (CO). At least a portion of the carbon monoxide in the gasified coal gas is converted into hydrogen (H2) and carbon dioxide via a shift converter and separator 41, resulting in a carbon dioxide concentration enriched to 50-60%. This enrichment of carbon components and increases the carbon dioxide concentration before separation, which helps reduce the energy consumption for carbon dioxide separation, thus achieving a synergistic conversion of low-energy decarbonization and efficient hydrogen production. The product gas CO can also bypass the shift converter to produce H2 and be directly coupled with hydrogen production from new energy sources to adjust the C / H ratio for chemical production, belonging to a "negative carbon" technology path.

[0102] According to embodiments of this disclosure, such as Figure 4 As shown, the cogeneration system also includes a pyrolysis gas treatment device 5, which is connected to the pyrolysis gas exhaust port of the pyrolysis section 102 and is suitable for separating at least a portion of the coal tar in the pyrolysis gas.

[0103] In this implementation, the high-calorific-value, high-temperature pyrolysis gas can be directly fed into various industrial kilns and furnaces at high temperature for combustion and energy supply. The pyrolysis gas from which coal tar is separated can be sent to industrial kilns and furnaces for combustion and energy supply, or methane and hydrogen products can be extracted through cryogenic and adsorption methods.

[0104] In one illustrative embodiment, such as Figure 4 As shown, the pyrolysis gas treatment equipment 5 includes an indirect cooler 52 and an electrostatic precipitator 51, which are sequentially connected to the pyrolysis gas outlet of the pyrolysis section. In this way, the high-temperature pyrolysis gas can be indirectly cooled to precipitate coal tar, and at least a portion of the coal tar remaining in the pyrolysis gas can be removed by the electrostatic precipitator 51, thereby achieving the separation of pyrolysis gas and coal tar.

[0105] According to embodiments of this disclosure, such as Figure 4 As shown, the cogeneration system also includes a raw coal input device 2, which is located upstream of the feed inlet 101 of the vertical pyrolysis equipment and is suitable for storing and inputting raw coal to be pyrolyzed into the external heat vertical pyrolysis-gasification unit.

[0106] In one illustrative embodiment, such as Figure 4 As shown, the raw coal input device 2 includes a dryer 21 and a coal hopper 22. The dryer 21 is suitable for receiving and drying the raw coal. The coal hopper 23 is located between the dryer 21 and the feed inlet of the vertical pyrolysis equipment to temporarily store the raw coal.

[0107] In one illustrative embodiment, such as Figure 4 As shown, the cogeneration system also includes a waste heat boiler 3. Specifically, the medium-temperature flue gas (including but not limited to 500°C to 600°C) from the pyrolysis section 102 passes through the hot side of the waste heat boiler 3 to heat the water on the cold side, thereby producing steam for external use. Furthermore, the low-temperature flue gas (including but not limited to 100°C to 200°C) after heat exchange in the waste heat boiler 3 is returned to the dryer 21 to further utilize the waste heat for drying the raw coal.

[0108] In this implementation, the comprehensive cascade utilization of high-temperature flue gas is achieved through external air combustion. Firstly, the high-temperature flue gas (1200-1700℃) is used for the coal-coke-CO2 gasification reaction (energy supply for the gasification process). The medium-high temperature flue gas (800-1000℃) produced from the gasification is further used for the pyrolysis process (energy supply for the pyrolysis reaction). Subsequently, the medium-temperature flue gas (500-800℃) is further utilized through a waste heat boiler for sensible heat recovery (waste boiler preheating). The flue gas (below 200℃) from the waste boiler is used for drying the raw coal. The high-temperature gasified coal gas from the gasification section heats the gasifying agent CO2.

[0109] It should also be noted that the directional terms mentioned in the embodiments, such as "up," "down," "front," "back," "left," and "right," are only for reference to the directions in the accompanying drawings and are not intended to limit the scope of protection of this disclosure. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or constructions will be omitted where they may cause confusion in understanding this disclosure.

[0110] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. An externally heated vertical pyrolysis-gasification integrated device, characterized in that, include: The furnace body (1) has an upper part that defines a pyrolysis section (102), and the interior of the pyrolysis section (102) is provided with a plurality of pyrolysis chambers suitable for containing raw coal pyrolysis. The lower part of the furnace body (1) defines a gasification section (105), and the interior of the gasification section (105) is provided with a gasification chamber suitable for containing pyrolyzed coal coke and gasifying agent gasification. Both the pyrolysis chamber and the gasification chamber are constructed as indirect heating external heating structures. The pyrolysis chamber is equipped with a first exhaust port for discharging pyrolysis gas, and the gasification chamber is equipped with a second exhaust port (113) for discharging gasified coal gas. A transition section (104) is formed between the pyrolysis section (102) and the gasification section (105) to connect the pyrolysis chamber and the gasification chamber, and the second exhaust port (113) is disposed in the transition section (104). The diameter of the transition section (104) is configured to be smaller than that of the pyrolysis section (102) and the gasification section (105).

2. The externally heated vertical pyrolysis-gasification integrated device according to claim 1, characterized in that, The gasification section (105) is provided with an inner furnace wall (111) extending vertically inside. The interior of the inner furnace wall (111) defines the gasification chamber. The exterior of the inner furnace wall (111) and the outer furnace wall of the furnace body (1) define a flue, which is suitable for accommodating the passage of flue gas used as a heat source and indirectly heating the coke in the gasification chamber.

3. The externally heated vertical pyrolysis-gasification integrated device according to claim 2, characterized in that, The inner furnace wall (111) is provided with a plurality of tubular components (117). The plurality of tubular components (117) are arranged at intervals in the vertical direction and extend in the horizontal direction. Each tubular component (117) penetrates the two opposite sides of the inner furnace wall (111) to communicate with the flue and guide the flue gas through the interior of the gasification chamber.

4. The externally heated vertical pyrolysis-gasification integrated device according to claim 3, characterized in that, It also includes multiple pairs of burners (110), with two burners (110) in each pair symmetrically arranged at both ends of the axial direction of one of the tubular components (117), and in the orthographic projection in the vertical direction, the combustion position of the burner (110) at least partially coincides with the gasification chamber.

5. The externally heated vertical pyrolysis-gasification integrated device according to any one of claims 2 to 4, characterized in that, The pyrolysis section (102) is internally spaced with a plurality of pyrolysis chambers; Each of the pyrolysis chambers is provided with an inlet (101) at the top for inputting the raw coal, and the lower part of each of the pyrolysis chambers is connected to the upper part of the gasification chamber.

6. The externally heated vertical pyrolysis-gasification integrated device according to claim 5, characterized in that, The flue formed within the gasification section (105) is also configured to communicate with the shell side of the pyrolysis section (102) outside the pyrolysis chamber, so that the flue gas passing through the gasification section (105) is also used as a heat source for the pyrolysis section (102).

7. The externally heated vertical pyrolysis-gasification integrated device according to any one of claims 2 to 4, characterized in that, It also includes a grate (106), which is rotatably disposed at the lower part of the inner furnace wall (111) and is suitable for receiving the ash and slag after gasification. The outer edge of the grate (106) and the inner wall of the inner furnace wall (111) form the discharge end of the gasification chamber.

8. The externally heated vertical pyrolysis-gasification integrated device according to claim 7, characterized in that, The gasification section (105) is provided with a gasification agent inlet (107) suitable for introducing gasification agent into the gasification chamber. The gasifying agent inlet (107) is located below the grate (106).

9. A cogeneration system, characterized in that, include: The externally heated vertical pyrolysis-gasification integrated apparatus as described in any one of claims 1 to 8, wherein the pyrolysis section (102) of the externally heated vertical pyrolysis-gasification integrated apparatus is adapted to output hydrogen-rich pyrolysis gas, and the gasification section (105) of the externally heated vertical pyrolysis-gasification integrated apparatus is adapted to output gasified coal gas containing carbon monoxide; and The gasification gas treatment equipment (4) is connected to the gasification section (105) and is suitable for accommodating the gasification gas and supplying steam to produce hydrogen through at least a portion of the carbon monoxide in the gasification gas.

10. The system according to claim 9, characterized in that, The gasification gas treatment equipment (4) includes: The converter and separator (41) defines a reaction chamber suitable for containing the gasified coal gas and water vapor to undergo a conversion reaction to produce hydrogen and separate carbon dioxide; A carbon dioxide storage tank (43), connected to the converter and separator (41), is suitable for collecting carbon dioxide; and A carbon dioxide preheater (42) is installed between the carbon dioxide storage tank (43) and the gasification section (105) of the externally heated vertical pyrolysis-gasification integrated device. It is equipped with a hot side suitable for accommodating the gasified coal gas and a cold side suitable for accommodating the carbon dioxide, so that the gasified coal gas and carbon dioxide exchange heat and the carbon dioxide is supplied to the gasification section (105) as a gasifying agent.

11. The system according to claim 9, characterized in that, It also includes a pyrolysis gas treatment device (5), which is connected to the pyrolysis gas exhaust port of the pyrolysis section (102) and is suitable for separating at least a portion of the coal tar in the pyrolysis gas.

12. The system according to any one of claims 9 to 11, characterized in that, It also includes a raw coal input device (2), which is located upstream of the feed inlet (101) of the externally heated vertical pyrolysis-gasification integrated device and is suitable for storing and inputting raw coal to be pyrolyzed into the externally heated vertical pyrolysis-gasification integrated device.

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