A novel solid fuel conversion apparatus and a pulverized coal gasification conversion method thereof

Abstract

The present application relates to the technical field of fuel conversion, in particular to a novel solid fuel conversion equipment and a pulverized coal gasification conversion method thereof, which comprises a furnace body, a ignition burner arranged at the top of the furnace body, a lifting unit, a gas-solid separation unit, an atomization cooling unit and a dry filtering unit, a plurality of independent nozzles are arranged at the top of the furnace body in an interval manner, and a plurality of secondary feeding nozzles are arranged at the middle of the furnace body in an interval manner; by arranging the independent nozzles, the high temperature caused by the rapid combustion near the burner is avoided, and the burner is prevented from being damaged; by the secondary feeding, the high-temperature synthesis gas is preliminarily cooled, and the solid particle circulation is formed in the middle of the furnace body, so that the synthesis gas is further cooled, and the atomized molten ash slag is solidified into small particles, the molten slag is not collected, and the water quenching cooling is not needed in the furnace body; the equipment has no coal burner, the production process does not form the accumulated molten slag block, and no black water and ash water is generated; the conversion method is simple in operation, stable in running and efficient in conversion.

Description

Technical Field

[0001] This invention relates to the field of fuel conversion technology, and in particular to a novel solid fuel conversion device and its coal powder gasification conversion method. Background Technology

[0002] In coal conversion technology, gasifiers have been industrially applied. Among them, fluidized bed gasifiers offer advantages such as high efficiency and large capacity, but they also have limitations in application. These limitations primarily manifest in low equipment and system availability and high sensitivity to fluctuations in coal type and quality. The oxy-coal burner is one of the core components of a fluidized bed gasifier. Whether using wet coal-water slurry feeding or dry pulverized coal feeding, the need to handle high-speed solid fluids and operate at extreme temperatures for extended periods leads to erosion and thermal stress, resulting in a burner lifespan typically less than two months. This necessitates periodic shutdowns for burner replacement, increasing maintenance costs and significantly reducing production efficiency. Furthermore, the high-temperature chemical erosion of refractory materials by molten slag also limits their lifespan, impacting production reliability and availability, and causing high maintenance costs. Additionally, the fluidized bed quenches the syngas together with the molten slag, resulting in the loss of some of the syngas's sensible heat, affecting the overall energy efficiency of the process. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a novel solid fuel conversion device and its coal powder gasification conversion method. The conversion device of this invention has a simple structure, reasonable design, stable operation, and high energy efficiency; the conversion method of this invention is easy to operate and has high conversion efficiency.

[0004] The technical solution adopted in this invention is:

[0005] A novel solid fuel conversion device includes a furnace body, with an ignition burner at the top and a discharge port at the bottom. It also includes a lifting unit, a gas-solid separation unit, an atomizing cooling unit, and a dry filtration unit. The lifting unit has an air inlet, an air outlet, and a slag outlet. The air inlet is connected to the bottom of the furnace body and the gas-solid separation unit, the air outlet is connected to the gas-solid separation unit and the atomizing cooling unit, the slag outlet is connected to the gas-solid separation unit and the middle section of the furnace body, and the dry filtration unit is connected to the atomizing cooling unit. The top of the furnace body has several spaced-apart independent nozzles, and the middle section of the furnace body has several spaced-apart secondary feeding nozzles.

[0006] Furthermore, the interior of the furnace body is a straight hollow cylinder.

[0007] Furthermore, the independent nozzle includes a feeding nozzle, an air supply nozzle, and an auxiliary nozzle.

[0008] Furthermore, the burner is located at the center of the top of the furnace body, and a plurality of feeding nozzles are spaced apart on the outer periphery of the burner, and a plurality of gas supply nozzles are spaced apart on the outer periphery of the plurality of feeding nozzles.

[0009] Furthermore, the furnace body is provided with a central pipe at the top, and a number of annular channels composed of concentric rings are provided on the outside of the central pipe. The gas supply nozzle is connected to the central pipe, and the number of feeding nozzles are respectively connected to the number of annular channels. The central pipe has a circulating semi-coke interface.

[0010] Furthermore, the air inlet is provided with a riser pipe, which is connected to the bottom of the furnace body and the gas-solid separation unit respectively. A primary cooling water supply assembly is provided on the riser pipe. The slag outlet is provided with a material leg and a return pipe, which is connected to the furnace body and the material leg respectively. The gas-solid separation unit is connected to the material leg. A fluidizing gas supply port is provided at the material leg. An auxiliary flow gas supply port is provided at one end of the return pipe near the furnace body.

[0011] Furthermore, the end of the return pipe that connects to the furnace body has multiple branch pipes.

[0012] Furthermore, the atomizing cooling unit includes a bypass pipe and a main pipe that are connected to each other at both ends. The main pipe is equipped with a cooling water supply assembly, and the bottom of the main pipe is equipped with a water collection assembly.

[0013] The coal pulverized gasification conversion method using the above-mentioned conversion equipment includes the following steps:

[0014] Prepare coal powder by grinding coal lumps into coal powder and separating them into main coal powder and micro coal powder according to particle size, and set them aside for use;

[0015] The equipment is preheated by ignition burners that use liquid or gaseous fuel mixed with air for combustion, and the resulting hot flue gas preheats the furnace body and its downstream units.

[0016] Add pulverized coal, gradually introducing the main pulverized coal and pure oxygen from the top of the furnace, and the furnace will then be put into operation;

[0017] Secondary coal powder is added, and micro powder is sprayed into the middle of the gasifier. The micro powder reacts with the high-temperature syngas after contact, which cools the gas. At the same time, the lower-temperature circulating solid enters the lower part of the gasifier and continues to cool the high-temperature gas after contact with the gas, so that the molten droplets in the gas solidify into small solid particles.

[0018] Entering the downstream unit for processing, the gas-solid fluid enters the riser from the bottom of the furnace body. The residual carbon continues to react in the riser. Then, it is separated into gas and solid particles by the gas-solid separation unit. The gas is divided into two paths. The main gas path enters the water atomization cooling unit for cooling. Then, it is mixed with the bypass hot gas that has not been cooled by water spray to adjust the water vapor content. Then, it enters the dry separation unit to separate clean syngas and semi-coke. The solid particles are added from the middle and lower part of the furnace body to cool the gas and circulate with it. The semi-coke is pressurized and enters the circulating semi-coke inlet to mix with oxygen, so that the semi-coke is burned to exhaustion in a high concentration of oxygen atmosphere. When clean syngas is produced, the fuel of the ignition burner is switched to clean syngas, and the combustion air is switched to oxygen. An appropriate amount of water vapor or carbon dioxide is introduced into the ignition burner along with the oxygen to maintain the ignition burner temperature at a moderate level.

[0019] The furnace has entered normal operation and has begun efficient pulverized coal gasification and conversion.

[0020] Furthermore, during the preparation of pulverized coal, the coal is ground to a finer size of less than 150 micrometers, and at the same time dried to a moisture content of less than 5%. The coal is then divided into main pulverized coal with a particle size greater than 30 micrometers and micro pulverized coal with a particle size less than 30 micrometers.

[0021] The beneficial effects of this invention are as follows:

[0022] 1. The conversion device of the present invention includes a furnace body, wherein an ignition burner is provided at the top of the furnace body, and a discharge port is provided at the bottom of the furnace body. It also includes a lifting unit, a gas-solid separation unit, an atomizing cooling unit, and a dry filtration unit. The lifting unit has an air inlet, an air outlet, and a slag outlet. The air inlet is connected to the bottom of the furnace body and the gas-solid separation unit, respectively. The air outlet is connected to the gas-solid separation unit and the atomizing cooling unit, respectively. The slag outlet is connected to the gas-solid separation unit and the middle part of the furnace body, respectively. The dry filtration unit is connected to the atomizing cooling unit. The top of the furnace body has a plurality of spaced-apart independent nozzles, and the middle part of the furnace body has a plurality of spaced-apart secondary feeding nozzles. By setting up independent and separate feeding nozzles and gas supply nozzles, the rapid combustion near the burner and the resulting high temperature are avoided, thus preventing burner damage. At the same time, the invention has a secondary feeding nozzle in the middle of the furnace body. Through the secondary feeding nozzle, the secondary fed combustion material can initially cool the high-temperature syngas and form a solid particle circulation in the middle of the furnace body, which can further cool the syngas and solidify the mist-like molten ash into small particles. There is no slag accumulation, and there is no need for water quenching and cooling in the furnace body. The residual semi-coke in the riser continues to undergo gasification reaction, making full use of the sensible heat of the coal gas to generate coal gas, improving solid conversion efficiency. This equipment has no coal burner, and no slag lumps are formed during the production process, and no black water or ash water is generated.

[0023] 2. The conversion method of the present invention has no slag accumulation, does not require water quenching and cooling in the furnace, and has high conversion efficiency. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the present invention;

[0025] Figure 2 This is a schematic diagram of the arrangement structure of a feeding nozzle and an air supply nozzle according to the present invention;

[0026] Figure 3 for Figure 2 A cross-sectional schematic diagram of the arrangement structure of the feed nozzle and the air nozzle;

[0027] Figure 4 This is a schematic diagram of another configuration of the feeding nozzle and the air supply nozzle according to the present invention;

[0028] Figure 5 for Figure 4 A cross-sectional schematic diagram of the arrangement structure of the feed nozzle and the air nozzle;

[0029] Figure 6 This is a schematic diagram of another arrangement of the feeding nozzle and the air supply nozzle according to the present invention;

[0030] Figure 7 for Figure 6 A cross-sectional schematic diagram of the arrangement structure of the feed nozzle and the air nozzle;

[0031] Figure 8 This is a schematic diagram of the auxiliary nozzle arrangement structure of the present invention;

[0032] Figure 9 This is a cross-sectional structural diagram of the middle part of the furnace body of the present invention;

[0033] Explanation of reference numerals in the attached drawings: 1. Furnace body; 11. Burner; 12. Discharge port; 13. Independent nozzle; 131. Feed nozzle; 132. Water nozzle; 133. Auxiliary nozzle; 14. Secondary feed nozzle; 15. Central pipe; 151. Circulating semi-coke interface; 16. Annular channel; 2. Lifting unit; 21. Air inlet; 211. Lifting pipe; 2111. Primary cooling water supply assembly; 22. Air outlet; 23. Slag outlet; 231. Material leg; 2311. Fluidizing gas inlet; 232. Return pipe; 2321. Flow aid gas inlet; 2322. Branch pipe; 4. Atomizing cooling unit; 41. Bypass pipe; 42. Main pipe; 421. Cooling water supply assembly; 422. Overflow water collection assembly; 5. Dry filter unit. Detailed Implementation

[0034] The invention will now be further described with reference to the accompanying drawings.

[0035] like Figures 1-9As shown, the novel solid fuel conversion equipment described in this embodiment includes a furnace body 1, with a burner 11 at the top and a discharge port 12 at the bottom. It also includes a lifting unit 2, a gas-solid separation unit 3, an atomizing cooling unit 4, and a dry filtration unit 4. The lifting unit 2 has an air inlet 21, an air outlet 22, and a slag outlet 23. The air inlet 21 is connected to the bottom of the furnace body 1 and the gas-solid separation unit 3, the air outlet 22 is connected to the gas-solid separation unit 3 and the atomizing cooling unit 4, the slag outlet 23 is connected to the gas-solid separation unit 3 and the middle of the furnace body 1, and the dry filtration unit 4 is connected to the atomizing cooling unit 4. The top of the furnace body 1 has several spaced-apart... The furnace body 1 has several spaced secondary feeding nozzles 14 in its middle section. The independent nozzles 131 can supply auxiliary gases such as steam / carbon dioxide into the furnace body 1, and can also be used as inlets for oxygen or pulverized coal. The independent nozzles 131 are located at different heights at the top of the furnace body 1. Each layer of independent nozzles 131 enters the upper furnace body 1 tangentially, with different tangential angles. After the auxiliary gas enters the furnace body 1, it increases the disturbance and mixing of the gas-solid fluid at the top inner side of the furnace body 1, enhancing the mass transfer rate between gas and solid. The solid fuel entering the furnace body 1 contacts oxygen in the upper space and completes the main gasification reaction. Specifically, the furnace body 1 has an internal cylindrical shape, which differs from existing fluidized bed gasifiers. The furnace body 1 is a metal pressure vessel with a refractory and insulation layer inside. The inner side of the refractory and insulation layer is a high-temperature reaction space, and the insulation function of the refractory and insulation layer protects the outer side of the pressure-resistant metal from low-temperature conditions. This invention avoids the problem of rapid combustion and high temperature near the burner 11 by setting independently separated feeding nozzles 131 and 132, thus preventing damage to the burner 11. Simultaneously, this invention provides a secondary feeding nozzle 14 in the middle of the furnace body 1. Multiple secondary feeding nozzles 14 can be installed on the circumference of the middle part of the furnace body 1, pointing towards the center of the furnace body 1. This arrangement is mainly to ensure that the pulverized coal is fully dispersed and mixed with the high-temperature syngas, and to ensure that as much pulverized coal as possible is in direct contact with the high-temperature syngas, avoiding the formation of coal tar. Through the secondary feeding nozzles 14, the secondary fed pulverized coal can initially cool the high-temperature syngas, and the sensible heat of the high-temperature syngas is used for secondary pulverized coal gasification. The overall process has high gasification efficiency and low oxygen consumption. In addition, the airflow entering the lifting unit 2 from the bottom of the furnace body 1 carries a mixed flow of solid particles. After being separated by the gas-solid separation unit 3, the separated solids are connected to the middle part of the furnace body 1 through the slag discharge section of the lifting unit 2, which is equivalent to forming a solid particle circulation in the middle part of the furnace body 1.The cooler circulating particles enter furnace 1 and come into contact with the high-temperature syngas from the upper part of furnace 1, further cooling the syngas. This eliminates the need for water quenching within furnace 1, effectively preventing heat loss. The separated gas then passes through outlet 22 and sequentially enters atomizing cooling unit 4 and dry filtration unit 5. The filtered dust is discharged from the system, and the filtered gas enters downstream systems for further processing.

[0036] The burner 11 is located at the center of the top of the furnace body 1. A plurality of feeding nozzles 131 are spaced apart on the outer periphery of the burner 11, and a plurality of air supply nozzles 132 are spaced apart on the outer periphery of the feeding nozzles 131. (See also...) Figure 2 and Figure 3 In one configuration of the independent nozzle 13, a burner 11 is positioned at the center of the top of the furnace body 1. Multiple sets of feeding nozzles 131 are arranged around the burner 11. Within each set of feeding nozzles 131, air supply nozzles 132 are arranged around the feeding nozzle 131, with the feeding nozzle 131 as the center. Specifically, the air supply nozzles 132 can be tilted at a certain angle towards the feeding nozzle 131. (See also...) Figure 4 and Figure 5 In another configuration of the independent nozzle 13, a pipe section cast from refractory material is used as the feeding nozzle 131, positioned at the center of the top of the furnace body 1. Multiple air supply nozzles 132 are arranged within concentric circles of different diameters outside the feeding nozzle 131. The angle between the inner air supply nozzle 132 and the vertical direction is greater than the angle between the outer air supply nozzle 132 and the vertical direction. The extension lines of the multiple air supply nozzles 132 point towards the extension line of the feeding nozzle 131. (See also...) Figure 6 and Figure 7 In another embodiment, the furnace body 1 has a central pipe 15 at the top, and several annular channels 16 composed of concentric rings on the outside of the central pipe 15. The gas supply nozzle 132 is connected to the central pipe 15, and several feeding nozzles 131 are respectively connected to several annular channels 16. The central pipe 15 has a circulating semi-coke interface 151. Specifically, the central pipe 15 is a thick-walled metal pipe for oxygen and circulating semi-coke to enter. Circulating around the central pipe 15, annular channels 16 are formed by refractory material for pulverized coal to enter the furnace body 1. The thick-walled pipe design can avoid premixing of gas and combustion solids and avoid the premixed combustion effect caused by the premixing of the two, thereby avoiding damage to the burner 11 by high temperature and effectively extending the service life of the burner 11. In other embodiments, the position of the feeding burner 131 can be selectively set according to the solid fuel combustion requirements, and a gas supply burner 132 can be set around the feeding burner 131.

[0037] In this embodiment, the air inlet 21 is provided with a riser pipe 211, and a primary cooling water supply assembly 211 is provided on the riser pipe 211. The air inlet 21 is provided with a riser pipe 211, which is connected to the furnace body 1 and the gas-solid separation unit 3 respectively. The slag outlet 23 is provided with a material leg 231 and a return pipe 232, which is connected to the furnace body 1 and the material leg 231 respectively. The gas-solid separation unit 3 is connected to the material leg 231. Specifically, see Figure 8 A fluidizing gas inlet 2311 is provided at the material leg 231, and an auxiliary flow gas inlet 2321 is provided at one end of the return pipe 232 near the furnace body 1. In this embodiment, at the bottom outlet of the furnace body 1, the gas flow carries solid particles into the riser pipe 211 outside the furnace body 1. In the riser pipe 211, the residual carbon continues to undergo gasification reaction. The endothermic gasification reaction causes the gas and circulating particles to continue to cool down. At the top of the riser pipe 211, the gas-solid mixture enters the gas-solid separation unit 3. The separated solids are sent to the middle of the furnace body 1 through the material leg 231 and the return pipe 232. After the gas leaves the top of the gas-solid separation unit 3, it enters the atomization cooling unit 3 for processing. In this embodiment, the end of the return pipe 232 that is connected to the furnace body 1 has multiple branch pipes 2322. This arrangement can form a flow-limiting mechanism by changing the size design of the bottom of the material leg 231 and the upper part of the return pipe 232, which becomes the control point for the solid flow capacity, keeping the material leg 231 at a certain material level. A fluidizing gas inlet 2311 is provided at the lower part of the material leg 231 to assist the solid flow. The multiple branch pipes 2322 decomposed from the return pipe 232 can guide the solid in the material leg 231 to the surrounding area of ​​the furnace body 1, so that the solid particles are distributed as evenly as possible on the circumference of the furnace body 1. An auxiliary flow gas inlet 2321 is provided to introduce appropriate auxiliary flow gas, which helps the circulating particles enter the entire cross section of the furnace body 1.

[0038] The atomizing cooling unit 4 includes a bypass pipe 41 and a main pipe 42 connected at both ends. A cooling water delivery assembly 421 is installed inside the main pipe 42. The main pipe 42 is set at a slanted angle, and a water collection assembly 422 is installed at the bottom of the main pipe 42. In this embodiment, the gas entering the atomizing cooling unit 4 is divided into two paths. A certain amount of cooling water is sprayed into the main pipe 42 according to the proportion of coal processed by the furnace 1 through the cooling water delivery assembly 421. The gas in the bypass pipe 41 that has not been sprayed with water mixes with the gas in the main pipe 42, ensuring that the mixed gas is above its dew point temperature. Specifically, cooling water is sprayed into the syngas in the main pipe 42. The water evaporates, further cooling the syngas. The amount of water sprayed is proportional to the syngas production and can be calculated in advance. The amount of water sprayed is just enough to completely cool this portion of the syngas. At this time, the syngas... The water vapor content is basically saturated. The obliquely arranged main pipe 42 facilitates the settling of un-atomized water droplets at the bottom of the inner side of the pipe. Internal mechanisms, such as impact separation or cyclone separation, can also be installed to assist in separating excess water from the gas. Excess water will be collected in the excess water collection component 422. Before the main pipe 42 and the bypass pipe 41 are merged, the excess water droplets carried in the gas are separated. The cooled gas leaving the main pipe 42 is mixed with the hot gas from the bypass pipe 41. The temperature of the mixed gas is between the temperatures of the two airflows, and the temperature of the mixed gas is also higher than its dew point. The choice of the temperature after mixing mainly depends on the allowable conditions of the selected dry dust collector. An adjustable device is installed in the bypass pipe 41 to change the proportion of the gas flow rate in the bypass pipe 41, so that the mixing temperature is controlled in a moderate range, generally between 300 and 500°C.

[0039] The dry filtration unit 5 is equipped with a dry filter, which uses a filter element made of ceramic or sintered metal. In this embodiment, the dry filter removes fly ash to purify the syngas. The collected fly ash is discharged from the bottom of the dry dust collector through a pressure reduction system. The syngas after dust removal enters the downstream for further processing. The fine ash collected by the dry dust collector is initially separated according to the difference in particle size and density after being discharged from the pressure reduction system, resulting in a portion with a higher semi-coke content and a portion with a lower carbon content. The portion with a higher semi-coke content is recycled and sent to the top of the furnace body 1, where the semi-coke is burned off in the oxygen-rich zone within the furnace body 1. This invention uses dry dust removal, and no black water or ash water is generated.

[0040] Coal pulverization conversion method using the above-mentioned conversion equipment:

[0041] Prepare pulverized coal by grinding it to below 150 micrometers (or 100 mesh) and drying it to a moisture content of less than 5%. The pulverized coal is then divided into two parts based on particle size: larger than 30 micrometers (main pulverized coal) and smaller than 30 micrometers (micro-powder). The 30 micrometer size can be adjusted; this is a typical value. Main pulverized coal can be pressurized and fed using a coal lock and coal controller. Micro-powder can be pressurized and fed using a dry plunger pump or a coal-water slurry. Because the coal is divided into different particle sizes, it can be added to the top and middle sections of the furnace using two different types of coal feeding equipment. Since the coal particle size differs, the technical requirements for the pressurized coal feeding unit (coal feeder) are different. Compared to the traditional method of mixing coal together, this effectively reduces the overall technical requirements for coal feeding, making the coal feeding process simpler and easier to operate.

[0042] When furnace 1 starts running, fuel and air are mixed to preheat the ignition burner and its downstream units. Then, pulverized coal and pure oxygen are gradually added, and normal operation begins. After clean syngas is produced, the fuel for the ignition burner is switched to syngas, and the combustion air is switched to oxygen. An appropriate amount of water vapor or carbon dioxide is introduced into the ignition burner along with the oxygen to maintain a moderate ignition burner temperature. During operation, the main pulverized coal is pressurized, and then carbon dioxide is used to transport the pulverized coal into furnace 1. Oxygen is transported into furnace 1 according to the pulverized coal ratio. As the load in furnace 1 increases, the addition ratio is adjusted. Pulverized coal and oxygen come into contact in the upper space of furnace 1 and undergo pyrolysis, complete combustion, incomplete combustion, and gasification reactions. The carbon dioxide used to transport the pulverized coal, as well as the additionally added carbon dioxide and water vapor, also participate in the gasification reaction as gasification reactants. To enhance the mixing and mass transfer between pulverized coal, oxygen, and gasification reactants, thereby improving the overall reaction rate and efficiency, the oxygen nozzle settings and oxygen flow distribution are optimized according to the operating conditions. At the same time, the additional carbon dioxide / water vapor gas nozzle settings and flow distribution are also coordinated according to the operating conditions to promote gas-solid contact and gas-solid chemical reaction. The high-concentration semi-coke separated by the dry filter unit 5 is recycled. After being pressurized, it enters the furnace body 1 through the circulating semi-coke interface 151 and mixes with oxygen. Once it leaves the oxygen channel, the oxygen participates in combustion, while the semi-coke is burned to exhaustion in a high-concentration oxygen atmosphere.

[0043] By adjusting the overall oxygen / coal ratio, the gasification reaction in the upper part of furnace 1 is carried out at extremely high temperatures, maximizing the coal processing capacity of furnace 1. Initially, partial combustion occurs with oxygen, resulting in a maximum gasification temperature of 1300–1600°C. Subsequently, semi-coke continues to rapidly gasify with water vapor and carbon dioxide at high temperatures to generate syngas. At this high temperature, the organic matter in the coal is rapidly converted into gaseous products. Simultaneously, the temperature of the gasification environment is generally higher than the melting point of most inorganic ash in the coal, causing most ash particles to transition from a solid state to a liquid state. Because the coal particles entering the furnace are small, generally less than 100 micrometers, and the size of the primary fine ash particles and their droplets is also small, droplets have the opportunity to aggregate during collisions, increasing their size. However, overall, the concentration of droplets within the syngas space remains low, so the solid particles or droplets leaving the high-temperature zone in the upper part of furnace 1 remain relatively small. The high-temperature syngas generated at the top of furnace body 1 carries fine-sized particles / droplets of ash downwards into the middle and lower spaces of furnace body 1. During this process, the high-temperature syngas flow rate is relatively low, maintaining a basically laminar flow state, with fewer opportunities for collision and aggregation of ash droplets.

[0044] In the middle of furnace body 1, secondary pulverized coal, in a certain proportion to the gasified pulverized coal from the upper part, is injected into the internal space of furnace body 1 and rapidly mixes with the high-temperature syngas coming down from the upper space. The syngas still contains carbon dioxide and water vapor. Upon contact with the high-temperature syngas, the secondary pulverized coal rapidly heats up, undergoing pyrolysis and subsequent gasification reactions, converting the organic matter in the secondary pulverized coal into syngas. The pyrolysis reaction of the secondary pulverized coal, especially the gasification reaction, is an endothermic reaction, which lowers the temperature of the mixed gas stream.

[0045] Meanwhile, circulating solid particles from gas-solid separation unit 3 enter the lower middle part of furnace body 1. The lower-temperature solid particles come into contact with the high-temperature coal gas, further cooling the coal gas. The molten ash droplets in the high-temperature coal gas also cool down until they solidify into small solid particles. At the bottom of furnace body 1, the coal gas carrying solid particles enters the riser pipe 211 on the outside of furnace body 1 through the arc-shaped pipe at the bottom of furnace body 1. During this process, the semi-coke that has not fully reacted in the secondary coal powder continues to undergo gasification reaction with carbon dioxide and water vapor in riser pipe 211. The endothermic reaction causes the rising gas-solid fluid to continue to cool down. In the upper section of riser pipe 211, a certain amount of water can be added to riser pipe 211 as needed. The evaporation of water further lowers the temperature of the gas-solid fluid. The gas-solid fluid enters the gas-solid separation unit 3. The separated solid particles are sent into the furnace 1 through the material leg 231 and the return pipe 232 to contact the high-temperature coal gas. The gas leaving the gas-solid separator enters the atomization cooling unit 4 and the dry filtration unit 5 for processing. The portion with a higher semi-coke content separated in the dry filtration unit 5 is sent into the furnace body 1 for circulation.

[0046] It should be noted that the embodiments of the present invention are illustrated using pulverized coal as an example. In fact, the operating temperature of the novel solid combustion conversion equipment of the present invention is not affected or is minimally affected by the ash content, ash chemical composition, ash melting point and ash melting point of the raw materials. The gasifier has a wide operating window and is suitable for the gasification of multiple coal types and non-coal solid combustibles (such as biomass, some sorted municipal waste and other residues / slags produced in coal conversion processes).

[0047] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A novel solid fuel conversion device, comprising a furnace body, wherein an ignition burner is provided at the top of the furnace body and a discharge port is provided at the bottom of the furnace body, characterized in that, It also includes a lifting unit, a gas-solid separation unit, an atomizing cooling unit, and a dry filtration unit. The lifting unit is provided with an air inlet, an air outlet, and a slag outlet. The air inlet is connected to the bottom of the furnace body and the gas-solid separation unit, respectively. The air outlet is connected to the gas-solid separation unit and the atomizing cooling unit, respectively. The slag outlet is connected to the gas-solid separation unit and the middle part of the furnace body, respectively. The dry filtration unit is connected to the atomizing cooling unit. The top of the furnace body is provided with several independently spaced nozzles, and the middle part of the furnace body is provided with several secondary feeding nozzles that are spaced apart. The independent nozzles include a feeding nozzle, an air supply nozzle, and an auxiliary nozzle; The ignition burner is located at the center of the top of the furnace body, and a plurality of feeding nozzles are spaced apart on the outer periphery of the ignition burner, and a plurality of gas supply nozzles are spaced apart on the outer periphery of the plurality of feeding nozzles. The air inlet section is equipped with a riser pipe, which is connected to the bottom of the furnace body and the gas-solid separation unit respectively. A primary cooling water supply assembly is provided on the riser pipe. The slag outlet section is equipped with a material leg and a return pipe, which is connected to the furnace body and the material leg respectively. The gas-solid separation unit is connected to the material leg. A fluidizing gas supply port is provided at the material leg. An auxiliary flow gas supply port is provided at one end of the return pipe near the furnace body.

2. The novel solid fuel conversion device according to claim 1, characterized in that, The furnace body has a straight hollow cylindrical shape inside.

3. The novel solid fuel conversion device according to claim 1, characterized in that, The end of the return pipe that connects to the furnace body has multiple branch pipes.

4. The novel solid fuel conversion device according to claim 1, characterized in that, The atomizing cooling unit includes a bypass pipe and a main pipe that are connected to each other at both ends. The main pipe is equipped with a cooling water supply assembly, and the bottom of the main pipe is equipped with a water collection assembly.

5. A coal pulverized gasification conversion method using the conversion equipment described in claim 4, characterized in that, Includes the following steps: Prepare coal powder by grinding coal lumps into coal powder and separating them into main coal powder and micro coal powder according to particle size, and set them aside for use; The equipment is preheated by ignition burners that use liquid or gaseous fuel mixed with air for combustion, and the resulting hot flue gas preheats the furnace body and its downstream units. Add pulverized coal, gradually introducing the main pulverized coal and pure oxygen from the top of the furnace, and the furnace will then be put into operation; Secondary coal powder is added, and micro powder is sprayed into the middle of the gasifier. The micro powder reacts with the high-temperature syngas after contact, which cools the gas. At the same time, the lower-temperature circulating solid enters the lower part of the gasifier and continues to cool the high-temperature gas after contact with the gas, so that the molten droplets in the gas solidify into small solid particles. Entering the downstream unit for processing, the gas-solid fluid enters the riser from the bottom of the furnace body. The residual carbon continues to react in the riser and then passes through the gas-solid separation unit to separate into gas and solid particles. The gas is divided into two paths. The main gas path enters the main pipe for cooling and then mixes with the bypass hot gas that has not been cooled by water spray. It then enters the dry separation unit to separate clean syngas and semi-coke. Solid particles are added from the lower part of the furnace body to cool the gas and circulate it with the gas. The semi-coke is pressurized and mixed with oxygen through the circulating semi-coke inlet, so that the semi-coke is burned to exhaustion in a high concentration of oxygen atmosphere. When clean syngas is produced, the fuel of the ignition burner is switched to clean syngas, and the combustion air is switched to oxygen. An appropriate amount of water vapor or carbon dioxide is introduced into the ignition burner along with the oxygen to maintain a moderate ignition burner temperature. The furnace has entered normal operation and has begun efficient pulverized coal gasification and conversion.

6. The coal pulverization conversion method according to claim 5, characterized in that, When preparing pulverized coal, the coal is ground to a finer size of less than 150 micrometers and dried to a moisture content of less than 5%. The coal is then divided into main pulverized coal with a particle size greater than 30 micrometers and micro pulverized coal with a particle size less than 30 micrometers.

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