System and method for utilizing high-chlorine coal

Abstract

The invention discloses a system and a method for utilizing high-chlorine coal, which are characterized in that high-chlorine raw coal is crushed by a crusher to a qualified particle size and then enters a raw coal bunker, and the raw coal in the raw coal bunker passes through a winnowing machine to reduce the dry basis ash content of the raw coal to meet the requirement of pulping raw coal; raw coal with the coal quality reaching the standard, an additive solution and water in the water storage tank enter the ball mill at the same time to be ground and stirred, and coal water slurry with the coal quality reaching the standard enters the slurry storage tank and finally reaches a thermal power plant through the conveying pump and the conveying pipeline. In a thermal power plant, coal water slurry is separated into low-chlorine and low-sodium coal with high moisture content and high-sodium and high-chlorine impurity-containing water through a dehydrator. The high-sodium and high-chlorine impurity-containing water is transported back to a coal mine through a pipeline after being subjected to a desalting and impurity-removing process, then enters a water storage tank and is continuously used as raw material water for preparing coal mine coal water slurry. Low-chlorine and low-sodium coal with high moisture content enters a coal yard and a coal mill of a thermal power plant to be milled into qualified pulverized coal after moisture is reduced through a drying machine, then the pulverized coal enters a hearth to be combusted, and a drying medium of the drying machine comes from low-pressure steam of a steam turbine.

Description

Technical Field

[0001] This invention belongs to the field of coal utilization technology, specifically relating to a system and method for utilizing high-chlorine coal, applicable to large-scale high-chlorine coal mines and large-capacity, high-parameter pulverized coal boilers. Background Technology

[0002] Because Shaerhu coal (high-chlorine, high-sodium coal, with chlorine content greater than 0.25%, and a maximum of greater than 1%, and Na2O content greater than 3% in coal ash) has severe corrosive, slagging, and fouling characteristics, it cannot be used alone in large-scale pulverized coal power plant boilers at present, and there is no long-term performance record of power plants co-firing it at a large proportion. As a result, high-chlorine coal mines in Xinjiang cannot be mined and utilized, resulting in a huge waste of resources. Summary of the Invention

[0003] In order to overcome the shortcomings of the existing technology, the purpose of this invention is to provide a system and method for utilizing high-chlorine coal, which is applicable to large-scale high-chlorine coal mines and large-capacity high-parameter pulverized coal boilers.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A system for utilizing high-chlorine coal includes a ball mill, a slurry storage tank, and a transfer pump arranged in a high-chlorine coal mine, and a dewatering machine, a desalination machine, a dryer, a coal mill, a pulverized coal boiler, and a water pump arranged in a thermal power plant. The water-coal slurry outlet of the ball mill is connected to the inlet of the slurry storage tank. The outlet of the slurry storage tank is connected to the inlet of the dewatering machine via a conveying pump and a conveying pipeline. The wastewater outlet of the dewatering machine is connected to the inlet of the desalination machine. The outlet of the desalination machine is connected to the water inlet of the ball mill via a water pump. The dewatering, desodium- and dechlorinating coal outlet of the dewatering machine is connected to the dewatering, desodium- and dechlorinating coal inlet of the dryer, the drying, desodium- and dechlorinating coal outlet of the dryer is connected to the inlet of the coal mill, and the outlet of the coal mill is connected to the inlet of the pulverized coal boiler.

[0005] A further improvement of the present invention is that it also includes a crusher, a raw coal bunker, a dry separator, an additive tank, and a water storage tank arranged in a high-chlorine coal mine. The outlet of the crusher is connected to the inlet of the raw coal bunker, the outlet of the raw coal bunker is connected to the inlet of the dry separator, and the outlet of the dry separator is connected to the high-chlorine coal inlet of the ball mill. The outlet of the additive tank is connected to the additive solution inlet of the ball mill. The outlet of the desalination machine is connected to the inlet of the water storage tank via a water pump, and the outlet of the water storage tank is connected to the water inlet of the ball mill.

[0006] A further improvement of the present invention is that it also includes a dryer located at the power plant's raw coal yard and a steam turbine, wherein the dryer's dried, desodium- and dechlorinated coal outlet is connected to the power plant's raw coal yard inlet, the power plant's raw coal yard outlet is connected to the coal mill inlet, a pulverized coal boiler is used to drive the steam turbine to generate electricity, and the steam turbine's low-pressure steam outlet is connected to the dryer's low-pressure steam inlet.

[0007] A further improvement of the present invention is that the high-chlorine coal is high-chlorine and high-sodium coal with a basic chlorine content of ≥0.2% and a Na2O content of ≥3.5% in the coal ash.

[0008] A method for utilizing high-chlorine coal, the method being based on the aforementioned system for utilizing high-chlorine coal, comprising: High-chlorine coal is processed into coal-water slurry in a ball mill and transported to a thermal power plant via pumps and pipelines. During transportation, chlorine and sodium in the coal dissolve into the water. A dewatering machine is then used to separate the coal and water, resulting in high-moisture coal that has been dehydrated, desodiumed, and dechlorinated, and wastewater containing sodium and chlorine. The high-moisture coal is then further dried in a dryer and stored in the power plant's raw coal yard. It is then fed into a coal mill via a conveyor belt to be ground into fine pulverized coal, which is then burned in a pulverized coal boiler, ultimately achieving safe combustion of high-chlorine coal in a large-capacity pulverized coal boiler. The separated wastewater is desalinated to remove sodium, chlorine, and impurities before being pumped into the next coal washing stage for recycling.

[0009] A further improvement of this invention is that the qualified particle size requirement for raw coal after crushing by the crusher is less than 30mm; and the dry basis ash content of the coal after washing by the dry separator is less than 13%.

[0010] A further improvement of the present invention is that the ratio of water, coal and additives entering the ball mill is in the range of 60%-70%, 30%-40% and 0.5%-1.5%, respectively.

[0011] A further improvement of the present invention is that 70%-80% of the water used in the ball mill to produce coal-water slurry comes from circulating water, while the makeup water accounts for 20%-30%.

[0012] A further improvement of this invention is that the coal from the dewatering machine is required to have a total moisture content of ≤30% and a basic chloride content of ≤0.15%; the coal from the dryer is required to have a total moisture content of 10-18%.

[0013] A further improvement of the present invention is that the heat source for drying pulverized coal in the dryer comes from the low-pressure gas source of the steam turbine, and the dryer adopts a steam pipe rotary drying method.

[0014] Compared with the prior art, the present invention has at least the following beneficial technical effects: 1) This invention enables the large-scale application of high-chlorine coal in pulverized coal boilers in power plants, solving the problem of difficult utilization of high-chlorine coal. 2) By converting high-chlorine coal from coal mines into coal-water slurry and transporting it to power plants via pipelines, the system is simple, mature, and has low transportation costs. 3) Through long-distance pipeline transportation, most of the harmful substances such as chlorine and sodium in the high-chlorine coal dissolve in the water, significantly reducing the chlorine and sodium content in the coal and greatly reducing the slagging, fouling, and corrosive properties of the coal sample. 4) A dewatering machine can separate coal and water in the coal-water slurry. 5) A dryer further reduces the moisture content of the dewatered coal sample, improving its fluidity and preventing blockage in the coal conveying system of thermal power plants. 6) The dryer uses a steam pipe rotary drying method, which has advantages such as simple process, large-scale equipment, mature technology, high safety, and high economy. 7) The dryer uses low-pressure steam from the turbine, improving the overall economic efficiency of the system. 8) This invention achieves the repeated recycling of water resources, resulting in significant water conservation. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of a system for utilizing high-chlorine coal according to the present invention.

[0017] Explanation of reference numerals in the attached figures: 1 is high-chlorine coal in a coal mine; 2 is a crusher; 3 is a raw coal bunker; 4 is a dry separator; 5 is a ball mill; 6 is an additive tank; 7 is a water storage tank; 8 is a slurry storage tank; 9 is a conveying pump; 10 is a conveying pipeline; 11 is a dewatering machine; 12 is a desalination machine; 13 is a dryer; 14 is a raw coal yard in a power plant; 15 is a coal mill; 16 is a pulverized coal boiler; 17 is a steam turbine; 18 is a water pump. Detailed Implementation

[0018] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0019] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0020] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0021] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0023] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0024] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0025] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0026] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0027] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0028] Example 1 refer to Figure 1 The present invention provides a system for utilizing high-chlorine coal, comprising a ball mill 5, a slurry storage tank 8, and a conveying pump 9 arranged in a high-chlorine coal mine, and a dewatering machine 11, a desalination machine 12, a dryer 13, a coal mill 15, a pulverized coal boiler 16, and a water pump 18 arranged in a thermal power plant; the water-coal slurry outlet of the ball mill 5 is connected to the inlet of the slurry storage tank 8, the outlet of the slurry storage tank 8 is connected to the inlet of the dewatering machine 11 via the conveying pump 9 and the conveying pipeline 10, the wastewater outlet of the dewatering machine 11 is connected to the inlet of the desalination machine 12, and the outlet of the desalination machine 12 is connected to the water inlet of the ball mill 5 via the water pump 18; the dewatered, desodium- and dechlorinated coal outlet of the dewatering machine 11 is connected to the dewatered, desodium- and dechlorinated coal inlet of the dryer 13, the dried, desodium- and dechlorinated coal outlet of the dryer 13 is connected to the inlet of the coal mill 15, and the outlet of the coal mill 15 is connected to the inlet of the pulverized coal boiler 16.

[0029] In this embodiment, the equipment also includes a crusher 2, a raw coal bunker 3, a dry separator 4, an additive tank 6, and a water storage tank 7 arranged in a high-chlorine coal mine. The outlet of the crusher 2 is connected to the inlet of the raw coal bunker 3, the outlet of the raw coal bunker 3 is connected to the inlet of the dry separator 4, and the outlet of the dry separator 4 is connected to the high-chlorine coal inlet of the ball mill 5. The outlet of the additive tank 6 is connected to the additive solution inlet of the ball mill 5. The outlet of the desalination machine 12 is connected to the inlet of the water storage tank 7 via a water pump 18, and the outlet of the water storage tank 7 is connected to the water inlet of the ball mill 5.

[0030] In this embodiment, the dryer 13 is connected to the inlet of the power plant's raw coal yard 14 and the steam turbine 17. The dryer 13's dried, desodium- and dechlorinated coal outlet is connected to the inlet of the power plant's raw coal yard 14, the outlet of the power plant's raw coal yard 14 is connected to the inlet of the coal mill 15, the pulverized coal boiler 16 is used to drive the steam turbine 17 to generate electricity, and the steam turbine 17's low-pressure steam outlet is connected to the steam inlet of the dryer 13.

[0031] In this embodiment, the high-chlorine coal is high-chlorine, high-sodium coal with a basic chlorine content of ≥0.2% and a Na2O content of ≥3.5% in the coal ash.

[0032] Example 2 refer to Figure 1 This invention provides a system for utilizing high-chlorine coal, comprising: a high-chlorine coal mine 1, a crusher 2, a raw coal bunker 3, a dry separator 4, a ball mill 5, an additive tank 6, a water storage tank 7, a slurry storage tank 8, and a conveying pump 9; and a power plant equipped with a dewatering machine 11, a desalination machine 12, a dryer 13, a power plant raw coal yard 14, a coal mill 15, a pulverized coal boiler 16, a steam turbine 17, and a water pump 18. A conveying pipeline 10 transports the coal-water slurry prepared at the coal mine to the power plant. The water pump 10 separates the wastewater from the coal-water slurry, which, after passing through the desalination machine 12, becomes clean water and is then returned to the coal mine for reuse via pipeline.

[0033] The water in the storage tank comes from the makeup water and the water after the coal-water slurry has undergone dewatering, desalination, and impurity removal processes. The dewatering machine is located within the power plant. After passing through the dewatering machine, the coal-water slurry is separated into low-chlorine, low-sodium, high-moisture coal and high-chlorine, high-sodium, high-salt water. The dehydrated, desodium- and dechlorinated coal from the dewatering machine is further dehydrated to within the safe range of the coal conveying system after passing through a dryer. The water in the storage tank comes from the desalination machine and the makeup water. The dryer dries the raw coal from the power plant's coal yard, which has undergone preliminary dewatering and dechlorination / sodium removal. The desiccant required for the dryer comes from the low-pressure steam from the turbine. The dehydrated, dechlorinated, and desodium-reduced raw coal, after passing through the dryer and meeting the moisture standards, enters the power plant's raw coal yard, where it is further ground into pulverized coal of a suitable fineness before being burned in the boiler for power generation.

[0034] Example 3 refer to Figure 1 The present invention provides a method for utilizing high-chlorine coal, comprising: High-chlorine raw coal from the coal mine is crushed to the qualified particle size by a crusher and then enters the raw coal bunker. The raw coal in the bunker is further reduced in dry basis ash content by an air classifier to meet the requirements for coal slurry preparation. The qualified raw coal, additive solution, and water from the storage tank are simultaneously fed into a ball mill for grinding and mixing. The qualified coal-water slurry enters the storage tank and is then transported by pumps and pipelines to the thermal power plant. At the thermal power plant, the coal-water slurry is separated by a dewatering machine into low-chlorine, low-sodium coal with higher moisture content and water with high sodium, high chlorine, and impurities. The water with high sodium, high chlorine, and impurities undergoes desalination and impurity removal processes before being transported back to the coal mine via pipeline and then enters the storage tank to continue as raw water for producing coal-water slurry.

[0035] The acceptable particle size requirement for raw coal after crushing is less than 30mm. After air separation, the coal must have a dry basis ash content of less than 13%. The water, coal, and additive ratios entering the ball mill are 60%-70%, 30%-40%, and 0.5%-1.5%, respectively, with 70%-80% of the water used in the coal-water slurry produced by the ball mill coming from the dewatering machine. The coal exiting the dewatering machine must have a total moisture content ≤30% and a basic chloride content ≤0.15%. The coal exiting the dryer must have a total moisture content of 10-18%.

[0036] Example 4 refer to Figure 1 The present invention provides a method for utilizing high-chlorine coal, comprising: High-chlorine coal is processed into coal-water slurry in ball mill 5 and transported to the power plant via conveying pump 9 and conveying pipeline 10. During transportation, chlorine and sodium in the coal dissolve into the water. The coal and water are then separated by dewatering machine 11, resulting in high-moisture coal that has been dehydrated, desodiumed, and dechlorinated, and wastewater containing sodium and chlorine. The high-moisture coal is then further dehydrated by dryer 13 and stored in the power plant's raw coal yard. It is then fed into coal mill 15 via conveyor belt to be ground into fine coal powder, which is then burned in pulverized coal boiler 16, ultimately achieving safe combustion of high-chlorine coal in a large-capacity pulverized coal boiler. The separated wastewater is desalinated by desalination machine 12 to remove sodium, chlorine, and impurities, and then pumped by water pump 18 into a water storage tank for the next coal conveying and washing process, thus achieving recycling.

[0037] Combustion of high-chlorinated coal in traditional pulverized coal boilers poses safety hazards, such as corrosion and slagging of boiler heating surfaces, affecting the safe operation and service life of the boiler. This invention achieves safe combustion of high-chlorinated coal in large-capacity pulverized coal boilers through a specific process, effectively solving this long-standing industry problem. This invention uses a ball mill to produce a coal-water slurry, utilizing the solubility of chlorine and sodium in water during transportation, combined with dehydration and desalination processes, forming a complete and unique high-chlorinated coal treatment and combustion process. This innovative process not only improves the utilization value of high-chlorinated coal but also provides a new and efficient coal processing method for thermal power plants.

[0038] This invention separates chlorine and sodium from coal by dissolving them in water, preventing these harmful substances from entering the atmosphere during combustion. This reduces pollutant emissions, such as chlorine oxides, from burning high-chlorine coal, thus contributing positively to improving ambient air quality. Furthermore, the separated wastewater is desalinated and recycled, achieving effective water conservation and zero or low emissions. This aligns with current environmental policies regarding water protection and recycling, and helps thermal power plants achieve green and sustainable development.

[0039] This invention pre-treats high-chlorine coal, enabling its safe combustion in large-capacity pulverized coal boilers. This fully utilizes the energy value of high-chlorine coal, improves the overall utilization efficiency of coal resources, and reduces resource waste caused by ineffective coal utilization. The treatment process first utilizes coal-water slurry to achieve initial separation of chlorine and sodium. Then, the coal undergoes further treatment through dehydration and drying. Finally, the desalinated water is recycled. This entire process embodies the cascade utilization of energy and resources, improving the comprehensive benefits of energy use.

[0040] From the ball mill's production of coal-water slurry to the transport via pumps and pipelines, and the coordinated operation of equipment such as dewatering machines, desalination machines, and dryers, the rational matching of each piece of equipment ensures the stable operation of the entire process. This rational equipment layout and process design helps improve production reliability and continuity, reducing production interruptions caused by equipment failures or process instability.

[0041] In this embodiment, the acceptable particle size requirement for raw coal after crushing by the crusher is less than 30mm; the coal after being washed by the dry separator is required to have a dry basis ash content of less than 13%.

[0042] In this embodiment, the ratios of water, coal, and additives entering the ball mill are in the ranges of 60%-70%, 30%-40%, and 0.5%-1.5%, respectively.

[0043] In this embodiment, 70%-80% of the water used in the ball mill to produce coal-water slurry comes from circulating water, while the makeup water accounts for 20%-30%.

[0044] In this embodiment, the coal from the dewatering machine is required to have a total moisture content of ≤30% and a basic chloride content of ≤0.15%; the coal from the dryer is required to have a total moisture content of 10-18%.

[0045] In this embodiment, the heat source for drying pulverized coal in the dryer comes from the low-pressure gas source of the steam turbine, and the dryer adopts a steam pipe rotary drying method.

[0046] In summary, the system and method for utilizing high-chlorine coal provided by this invention can utilize high-chlorine coal, which is currently not suitable for combustion in large pulverized coal boilers, for power generation in large pulverized coal boilers, thus making use of huge coal resources. It is applicable to high-chlorine coal mines and large pulverized coal power plant boilers.

[0047] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0048] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A system for utilizing high-chlorine coal, characterized in that, This includes ball mills (5), slurry tanks (8), and transfer pumps (9) installed in high-chlorine coal mines, and dewatering machines (11), desalination machines (12), dryers (13), coal mills (15), pulverized coal boilers (16), and water pumps (18) installed in thermal power plants. The water-coal slurry outlet of the ball mill (5) is connected to the inlet of the slurry storage tank (8). The outlet of the slurry storage tank (8) is connected to the inlet of the dewatering machine (11) via the conveying pump (9) and the conveying pipeline (10). The wastewater outlet of the dewatering machine (11) is connected to the inlet of the desalination machine (12). The outlet of the desalination machine (12) is connected to the water inlet of the ball mill (5) via the water pump (18). The dewatering, desodium- and dechlorinating coal outlet of the dewatering machine (11) is connected to the dewatering, desodium- and dechlorinating coal inlet of the dryer (13), the drying, desodium- and dechlorinating coal outlet of the dryer (13) is connected to the inlet of the coal mill (15), and the outlet of the coal mill (15) is connected to the inlet of the pulverized coal boiler (16).

2. The system for utilizing high-chlorine coal according to claim 1, characterized in that, It also includes a crusher (2), a raw coal bunker (3), a dry separator (4), an additive tank (6), and a water storage tank (7) arranged in a high-chlorine coal mine. The outlet of the crusher (2) is connected to the inlet of the raw coal bunker (3), the outlet of the raw coal bunker (3) is connected to the inlet of the dry separator (4), the outlet of the dry separator (4) is connected to the high-chlorine coal inlet of the ball mill (5), the outlet of the additive tank (6) is connected to the additive solution inlet of the ball mill (5), the outlet of the desalination machine (12) is connected to the inlet of the water storage tank (7) via a water pump (18), and the outlet of the water storage tank (7) is connected to the water inlet of the ball mill (5).

3. The system for utilizing high-chlorine coal according to claim 2, characterized in that, It also includes the coal yard (14) and the steam turbine (17) of the power plant. The dryer (13)’s dryer’s desodium and dechlorinated coal outlet is connected to the inlet of the coal yard (14) of the power plant. The outlet of the coal yard (14) of the power plant is connected to the inlet of the coal mill (15). The pulverized coal boiler (16) is used to drive the steam turbine (17) to generate electricity. The low-pressure steam outlet of the steam turbine (17) is connected to the low-pressure steam inlet of the dryer (13).

4. The system for utilizing high-chlorine coal according to claim 1, characterized in that, The high-chlorine coal is high-chlorine, high-sodium coal with a basic chlorine content of ≥0.2% and a Na2O content of ≥3.5% in the coal ash.

5. A method for utilizing high-chlorine coal, characterized in that, This method, based on a system for utilizing high-chlorine coal as described in claim 3, includes: High-chlorine coal is processed into coal-water slurry in a ball mill (5), and transported to the thermal power plant via a conveying pump (9) and a conveying pipeline (10). During the transportation process, the chlorine and sodium in the coal dissolve into the water. The coal and water are then separated by a dewatering machine (11) to obtain high-moisture coal that has been dehydrated, desodium- and dechlorinated, and wastewater containing sodium and chlorine. The high-moisture coal is then further dehydrated by a dryer (13) and stored in the raw coal yard of the power plant. It is then fed into a coal mill (15) via a coal conveyor belt to be ground into fine coal powder that meets the required fineness and then burned in a pulverized coal boiler (16). This process ultimately achieves the safe combustion of high-chlorine coal in a large-capacity pulverized coal boiler. The separated wastewater is then desalinated by a desalination machine (12) to remove sodium, chlorine and impurities, and then pumped by a water pump (18) into the next coal conveying and washing stage for recycling.

6. The method for utilizing high-chlorine coal according to claim 5, characterized in that, The acceptable particle size requirement for raw coal after crushing is less than 30mm; the dry ash content of coal after washing by a dry separator is required to be less than 13%.

7. The method for utilizing high-chlorine coal according to claim 5, characterized in that, The proportions of water, coal, and additives entering the ball mill are in the ranges of 60%-70%, 30%-40%, and 0.5%-1.5%, respectively.

8. A method for utilizing high-chlorine coal according to claim 5, characterized in that, In ball mills, 70%-80% of the water used to produce coal-water slurry comes from circulating water, while makeup water accounts for 20%-30%.

9. A method for utilizing high-chlorine coal according to claim 5, characterized in that, The coal from the dewatering machine must have a total moisture content of ≤30% and a basic chloride content of ≤0.15%; the coal from the dryer must have a total moisture content of 10-18%.

10. A method for utilizing high-chlorine coal according to claim 5, characterized in that, The heat source for drying pulverized coal in the dryer comes from the low-pressure gas source of the steam turbine, and the dryer adopts a steam pipe rotary drying method.

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