High alkali metal coal slag adhering method

Abstract

The invention is suitable for the technical field of coal, and provides a high alkali metal coal slag adhering method, which comprises the following steps: step 1, analyzing the occurrence form and content of alkali metal: firstly, analyzing the occurrence form and content of alkali metal in coal, including four forms of water-soluble alkali metal, ammonium acetate solubility, diluted hydrochloric acid solubility and insoluble alkali metal, according to the invention, the slag adhering problem of the high alkali metal coal is reduced, the combustion efficiency and environmental protection property of the coal are improved, the combustion and gasification efficiency of the coal is improved, the environmental pollution is reduced, through reasonable coal blending, the utilization efficiency of coal resources is improved, the production cost is reduced, the low alkali coal can be effectively utilized to improve the combustion characteristics of the high alkali coal, and the slag-bonding and contamination problems of a boiler are reduced; meanwhile, safe and economical operation of the boiler is guaranteed, the components of the coal ash can be effectively regulated and controlled, the utilization value of the coal ash is improved, the environmental influence is reduced, cyclic utilization of resources is achieved, and the slag adhering phenomenon of the high alkali metal coal in the combustion and gasification process can be more accurately predicted and controlled, so that effective prevention and solution measures are taken.

Description

Technical Field

[0001] The invention belongs to the technical field of coal, and in particular relates to a slagging method for high-alkali metal coal. Background Art

[0002] High-alkali coal slag refers to the molten slag formed during the combustion or gasification of coal due to the high concentration of alkali metals (such as sodium, potassium, etc.) and other minerals in the coal. Under high temperature conditions, these minerals will melt and react with other components in the coal ash to form molten slag. This molten slag is deposited on the heating surface of the boiler or gasifier to form slag. The slag phenomenon will lead to: reduced thermal efficiency: slag will cover the heating surface, reduce heat exchange efficiency, and increase energy consumption; equipment damage: slag may cause overheating of the heating surface and even damage the equipment; increased maintenance costs: slag needs to be cleaned regularly, increasing maintenance costs and downtime; environmental pollution: slag may contain harmful components, and its discharge may pollute the environment.

[0003] Therefore, high-alkali metal coal slag is a problem that needs to be focused on and solved during coal combustion and gasification. Summary of the invention

[0004] The present invention provides a method for slagging high-alkali metal coal, which aims to solve the problem that under high temperature conditions, these minerals will melt and react with other components in the coal ash to form molten slag. This molten slag is deposited on the heating surface of the boiler or gasifier to form a slagging phenomenon, which will lead to: reduced thermal efficiency: the slag will cover the heating surface, reduce the heat exchange efficiency, and increase energy consumption; equipment damage: the slag may cause the heating surface to overheat and even damage the equipment; increased maintenance costs: the slag needs to be cleaned regularly, which increases maintenance costs and downtime; environmental pollution: the slag may contain harmful components, and its discharge may cause environmental pollution.

[0005] The present invention is achieved by a method for slagging high-alkali metal coal, comprising the following steps:

[0006] Step 1: Analysis of the occurrence form and content of alkali metals: First, the occurrence form and content of alkali metals in coal need to be analyzed, including four forms: water-soluble, ammonium acetate-soluble, dilute hydrochloric acid-soluble, and insoluble alkali metals;

[0007] Step 2: Evolution of alkali metals during combustion: Study the evolution of alkali metals during the combustion of high-alkali coal, including the occurrence form of alkali metals, the formation of gaseous alkali metal compounds and their condensation process on the heating surface, and add slagging agents or combustion aids;

[0008] Step 3: Slag layer formation mechanism: Study the formation mechanism of slag layer during the combustion of high-alkali coal, including the formation of inner white layer, sintered layer and molten layer;

[0009] Step 4: Fuel pretreatment: Pretreatment of high-alkali coal, such as water washing, hydrothermal treatment, CO2-water pretreatment, acid washing, microwave treatment, ion exchange, etc., can reduce the content of alkali metals, alkaline earth metals and Fe in coal, and slow down the slagging phenomenon of boilers burning high-alkali coal;

[0010] Step 5. Reasonable coal blending: By blending high-alkali coal with low-alkali coal, the content of alkali metals in the mixed coal can be reduced so that the quality of the blended coal meets the requirements of boiler combustion. It is necessary to determine the target characteristics of the mixed coal, conduct index analysis on the Tianchi energy mixed coal and coal gangue to be used, provide raw coal industrial analysis, ash component analysis and ash viscosity analysis data, including key indicators such as calorific value, volatile matter, sulfur content, ash content, etc., and adjust the boiler design and operation parameters;

[0011] Step 6: Keep the heating surface clean: Keep the heating surface clean by treating the heat exchange surface, optimizing the boiler design and adjusting the operating conditions, and inhibit the condensation of alkali metals on the heating surface and the adhesion of fine particles on the heating surface;

[0012] Step 7: Blending low-alkali coal: Blending low-alkali coal can reduce the formation of liquid AAEM sulfate;

[0013] Step 8: Liquid slag discharge process: The liquid slag discharge process can effectively capture the alkali metals in the high-alkali coal, and discharge the low-temperature eutectic such as Na-Ca-Fe-Al-Si from the furnace in the form of liquid slag, thereby reducing the total amount of alkali metals near the subsequent heating surface and realizing the modification of fly ash;

[0014] Step 9, gasification test: Carry out gasification tests of high alkali metal and alkaline earth metal coal under different atmospheres, analyze the liquid phase growth law of ash slag by combining phase equilibrium calculation, and analyze the influence of coal ash component changes on ash fusibility through phase diagram;

[0015] Step 10: Control of coal ash components: By adjusting the relative contents of components such as SiO2, Al2O3, Na2O and CaO in the coal ash, the ash fusibility can be effectively controlled to prevent slagging.

[0016] Preferably, step three also includes an ash melting temperature test, and the ash melting temperature test is performed by using equipment such as an ash melting temperature tester, a thermomechanical analyzer, a thermogravimetric-differential scanning calorimeter, etc., so as to explore the slagging tendency and slagging process of high-alkali coal ash slag.

[0017] Preferably, step seven also includes studying the effects of different coal blending ratios and steam soot blowing on furnace outlet temperature and temperature rise, and calculating the furnace soot blowing operation time interval based on the furnace outlet temperature to control the burning ratio.

[0018] Preferably, the reasonable coal blending in step five includes determining the coal blending target, determining the target indicators of coal blending, such as calorific value, volatile matter, ash content, and sulfur content, according to the requirements of the boiler or coke oven; coal quality analysis, conducting detailed coal quality analysis on various coals involved in coal blending, including ash content, volatile matter, sulfur content, moisture content, and calorific value; coal type selection, selecting appropriate coal types for blending according to the coal blending target and the results of coal quality analysis, including selecting coal types with low ash content and low sulfur content to reduce pollutant emissions, or selecting coal types with high volatile matter to improve combustion efficiency; coal blending ratio calculation; coal blending test; adjustment and optimization; and real-time monitoring.

[0019] Preferably, the analysis method in step one includes an extraction method, and the specific steps are: water-soluble extraction; ammonium acetate-soluble extraction; hydrochloric acid-soluble extraction and insoluble extraction; low-temperature ashing method, ashing the coal sample under low-temperature conditions to reduce the release of alkali metals, thereby obtaining a more accurate measurement value.

[0020] Preferably, the step five also includes collecting characteristic data of each single type of coal; calculating the mixing ratio: according to the target characteristics and the data of the single type of coal, accurately measuring the weight of the coal, and calculating the mixing ratio; sampling detection, trial burning, adjusting parameters according to the results, and finally determining the coal ratio; specifically including: collecting the characteristic data of each single type of coal includes sampling the coal, analyzing the moisture, ash, volatile matter, sulfur content, and calorific value of the collected different coals, collating the analyzed data, establishing a database, analyzing and statistics the data in the database to obtain the distribution and correlation information of the characteristic parameters of the coal; calculating the mixing ratio specifically includes determining the target characteristics, clarifying the expected characteristics of the mixed coal, such as calorific value, volatile matter, sulfur content, ash content, and collecting data of the single type of coal.

[0021] Preferably, the blending of low-alkali coal in step seven also includes conducting a combustion test to verify the feasibility of the blending ratio and the combustion effect; boiler design adjustment, according to the coal quality characteristics after blending, it may be necessary to adjust the boiler design to adapt to the new coal characteristics, during the blending process, it is necessary to optimize the boiler operating parameters, and at the same time, during the blending process, closely monitor the operating conditions of the boiler, including exhaust gas temperature, plant power consumption rate, boiler combustion stability, boiler efficiency, and evaluate the impact of blending low-alkali coal on environmental protection, including the emissions of sulfur dioxide (SOx), nitrogen oxides (NOx), carbon monoxide (CO), organic compounds and dust particles.

[0022] Preferably, the liquid slag discharge process in step eight specifically includes high-temperature combustion; melting slag, using high temperature to melt the coal ash into liquid slag and discharge it out of the furnace; using a slag discharge system for slag discharge, the slag discharge system includes a lower slag slurry pump for discharging the molten slag from the bottom of the furnace; granulation treatment, through granulation treatment, it is converted into fine particles for subsequent processing and utilization; waste heat recovery; slag particle cooling.

[0023] Preferably, the gasification test in step nine specifically includes test design: selecting a suitable experimental method according to needs; fuel preparation, including pretreatment of the fuel; gasification agent selection, selecting a suitable gasification agent, such as air, oxygen, water vapor or a mixture thereof; test parameter setting, test operation; data collection; product analysis; and result evaluation.

[0024] Preferably, the control of the ash components in step ten specifically includes: extracting useful components from fly ash using mineral processing and separation technology; effectively controlling the ash fusibility by adjusting the relative contents of components such as SiO2, Al2O3, Na2O and CaO in the ash; and combining reasonable coal blending to mix low-melting-point coal with high-melting-point coal to increase the ash melting point of the mixed coal.

[0025] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0026] The present invention reduces the slagging problem of high-alkali metal coal, improves the combustion efficiency and environmental protection of coal, improves the combustion and gasification efficiency of coal, reduces environmental pollution, improves the utilization efficiency of coal resources and reduces production costs through reasonable coal blending, can effectively utilize low-alkali coal to improve the combustion characteristics of high-alkali coal, reduce boiler slagging and contamination problems, and ensure the safe and economical operation of the boiler at the same time, can effectively regulate the components of coal ash, improve its utilization value, reduce environmental impact, and realize the recycling of resources, and can more accurately predict and control the slagging phenomenon of high-alkali metal coal during combustion and gasification, so as to take effective prevention and solution measures. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the process structure of a high-alkali metal coal slagging method of the present invention; DETAILED DESCRIPTION

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0029] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0030] An embodiment of the present invention provides a method for slagging high-alkali metal coal, which includes the following steps as shown in the figure:

[0031] Step 1: Analysis of the occurrence form and content of alkali metals: First, the occurrence form and content of alkali metals in coal need to be analyzed, including four forms: water-soluble, ammonium acetate-soluble, dilute hydrochloric acid-soluble, and insoluble alkali metals;

[0032] Step 2: Evolution of alkali metals during combustion: Study the evolution of alkali metals during the combustion of high-alkali coal, including the occurrence form of alkali metals, the formation of gaseous alkali metal compounds and their condensation process on the heating surface, and add slagging agents or combustion aids;

[0033] Step 3: Slag layer formation mechanism: Study the formation mechanism of slag layer during the combustion of high-alkali coal, including the formation of inner white layer, sintered layer and molten layer;

[0034] Step 4: Fuel pretreatment: Pretreatment of high-alkali coal, such as water washing, hydrothermal treatment, CO2-water pretreatment, acid washing, microwave treatment, ion exchange, etc., can reduce the content of alkali metals, alkaline earth metals and Fe in coal, and slow down the slagging phenomenon of boilers burning high-alkali coal;

[0035] Step 5. Reasonable coal blending: By blending high-alkali coal with low-alkali coal, the content of alkali metals in the mixed coal can be reduced so that the quality of the blended coal meets the requirements of boiler combustion. It is necessary to determine the target characteristics of the mixed coal, conduct index analysis on the Tianchi energy mixed coal and coal gangue to be used, provide raw coal industrial analysis, ash component analysis and ash viscosity analysis data, including key indicators such as calorific value, volatile matter, sulfur content, ash content, etc., and adjust the boiler design and operation parameters;

[0036] Step 6: Keep the heating surface clean: Keep the heating surface clean by treating the heat exchange surface, optimizing the boiler design and adjusting the operating conditions, and inhibit the condensation of alkali metals on the heating surface and the adhesion of fine particles on the heating surface;

[0037] Step 7: Blending low-alkali coal: Blending low-alkali coal can reduce the formation of liquid AAEM sulfate;

[0038] Step 8: Liquid slag discharge process: The liquid slag discharge process can effectively capture the alkali metals in the high-alkali coal, and discharge the low-temperature eutectic such as Na-Ca-Fe-Al-Si from the furnace in the form of liquid slag, thereby reducing the total amount of alkali metals near the subsequent heating surface and realizing the modification of fly ash;

[0039] Step 9, gasification test: Carry out gasification tests of high alkali metal and alkaline earth metal coal under different atmospheres, analyze the liquid phase growth law of ash slag by combining phase equilibrium calculation, and analyze the influence of coal ash component changes on ash fusibility through phase diagram;

[0040] Step 10: Control of coal ash components: By adjusting the relative contents of components such as SiO2, Al2O3, Na2O and CaO in the coal ash, the ash fusibility can be effectively controlled to prevent slagging.

[0041] Step three also includes an ash melting temperature test, which is performed using an ash melting temperature tester, a thermomechanical analyzer, a thermogravimetric-differential scanning calorimeter and other equipment to explore the slagging tendency and slagging process of high-alkali coal ash slag.

[0042] Step seven also includes studying the effects of different coal blending ratios and steam soot blowing on the furnace outlet temperature and temperature rise, and calculating the furnace soot blowing operation time interval based on the furnace outlet temperature to control the burning ratio.

[0043] The reasonable coal blending in step five includes determining the coal blending target, determining the target indicators of coal blending, such as calorific value, volatile matter, ash content, and sulfur content, according to the requirements of the boiler or coke oven; coal quality analysis, conducting detailed coal quality analysis of various coals involved in coal blending, including ash content, volatile matter, sulfur content, moisture content, and calorific value; coal type selection, selecting appropriate coal types for blending according to the coal blending target and coal quality analysis results, including selecting low-ash and low-sulfur coal types to reduce pollutant emissions, or selecting high-volatile coal types to improve combustion efficiency; coal blending ratio calculation; coal blending test; adjustment and optimization; real-time monitoring.

[0044] The analysis method in step one includes an extraction method, and the specific steps are: water-soluble extraction; ammonium acetate-soluble extraction; hydrochloric acid-soluble extraction and insoluble extraction; low-temperature ashing method, ashing the coal sample under low-temperature conditions to reduce the release of alkali metals, thereby obtaining a more accurate measurement value.

[0045] Step five also includes collecting characteristic data of each type of coal; calculating the mixing ratio: based on the target characteristics and the data of the single coal, accurately measuring the weight of the coal and calculating the mixing ratio; sampling and testing, trial burning, adjusting parameters according to the results, and finally determining the coal ratio; specifically including: collecting characteristic data of each type of coal includes sampling coal, analyzing the moisture, ash, volatile matter, sulfur content, and calorific value of the collected different coals, collating the analyzed data, establishing a database, analyzing and statistics the data in the database to obtain the distribution and correlation information of the characteristic parameters of the coal; calculating the mixing ratio specifically includes determining the target characteristics, clarifying the expected characteristics of the mixed coal, such as calorific value, volatile matter, sulfur content, ash content, and collecting data of the single coal.

[0046] The blending of low-alkali coal in step seven also includes combustion tests to verify the feasibility of the blending ratio and the combustion effect; boiler design adjustment, according to the coal quality characteristics after blending, the boiler design may need to be adjusted to adapt to the new coal characteristics. During the blending process, the boiler operating parameters need to be optimized. At the same time, during the blending process, the operating conditions of the boiler are closely monitored, including exhaust gas temperature, plant power consumption rate, boiler combustion stability, boiler efficiency, and the impact of blending low-alkali coal on environmental protection is evaluated, including the emissions of sulfur dioxide (SOx), nitrogen oxides (NOx), carbon monoxide (CO), organic compounds and dust particles.

[0047] The liquid slag discharge process in step eight specifically includes high-temperature combustion; melting slag, using high temperature to melt the coal ash into liquid slag and discharge it out of the furnace; using a slag discharge system for slag discharge, the slag discharge system includes a lower slag slurry pump for discharging the molten slag from the bottom of the furnace; granulation treatment, through granulation treatment, it is converted into fine particles for subsequent processing and utilization; waste heat recovery; slag particle cooling.

[0048] The gasification test in step nine specifically includes test design: selecting a suitable experimental method according to needs; fuel preparation, including pretreatment of the fuel; gasification agent selection, selecting a suitable gasification agent, such as air, oxygen, water vapor or a mixture of these; test parameter setting, test operation; data collection; product analysis; and result evaluation.

[0049] The control of the ash components in step ten specifically includes: extracting useful components from fly ash using mineral processing and separation technology; effectively controlling the ash fusibility by adjusting the relative contents of components such as SiO2, Al2O3, Na2O and CaO in the ash; and combining reasonable coal blending to mix low-melting-point coal with high-melting-point coal to increase the ash melting point of the mixed coal.

[0050] Existing technology High alkali metal coal slag refers to the fact that during the combustion or gasification process of coal, due to the high concentration of alkali metals (such as sodium, potassium, etc.) and other minerals in the coal, these minerals will melt and react with other components in the coal ash under high temperature conditions to form molten slag. This molten slag is deposited on the heating surface of the boiler or gasifier to form slag phenomenon, which will lead to: reduced thermal efficiency: slag will cover the heating surface, reduce heat exchange efficiency, and increase energy consumption; equipment damage: slag may cause overheating of the heating surface and even damage the equipment; increased maintenance costs: slag needs to be cleaned regularly, increasing maintenance costs and downtime; environmental pollution: slag may contain harmful components, and its discharge may pollute the environment.

[0051] The present invention reduces the slagging problem of high-alkali metal coal, improves the combustion efficiency and environmental protection of coal, improves the combustion and gasification efficiency of coal, reduces environmental pollution, improves the utilization efficiency of coal resources and reduces production costs through reasonable coal blending, can effectively utilize low-alkali coal to improve the combustion characteristics of high-alkali coal, reduce boiler slagging and contamination problems, and ensure the safe and economical operation of the boiler at the same time, can effectively regulate the components of coal ash, improve its utilization value, reduce environmental impact, and realize the recycling of resources, and can more accurately predict and control the slagging phenomenon of high-alkali metal coal during combustion and gasification, so as to take effective prevention and solution measures.

[0052] It should be noted that, for the above-mentioned embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should know that the present invention is not limited by the described order of actions, because according to the present invention, some steps may be performed in other orders or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

[0053] In the several embodiments provided in the present application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are merely schematic, such as the division of the above-mentioned units. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or communication connection shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or units can be in the form of telecommunication or other forms.

[0054] The units described above as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0055] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the scope of protection of the invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in this field can still combine, add, delete or make other adjustments to the features in the various embodiments of the present invention according to the circumstances without conflict, without making creative work, so as to obtain different other technical solutions that do not deviate from the concept of the present invention in essence, and these technical solutions also belong to the scope of protection of the present invention.

Claims

1. A method for slagging high-alkali metal coal, characterized in that: The following steps are involved: Step 1: Analysis of the occurrence form and content of alkali metals: First, the occurrence form and content of alkali metals in coal need to be analyzed, including four forms: water-soluble, ammonium acetate-soluble, dilute hydrochloric acid-soluble, and insoluble alkali metals; Step 2: Evolution of alkali metals during combustion: Study the evolution of alkali metals during the combustion of high-alkali coal, including the occurrence form of alkali metals, the formation of gaseous alkali metal compounds and their condensation process on the heating surface, and add slagging agents or combustion aids; Step 3: Slag layer formation mechanism: Study the formation mechanism of the slag layer during the combustion of high-alkali coal, including the formation of the inner white layer, sintered layer and molten layer; Step 4: Fuel pretreatment: Pretreatment of high-alkali coal, such as water washing, hydrothermal treatment, CO2-water pretreatment, acid washing, microwave treatment, ion exchange, etc., can reduce the content of alkali metals, alkaline earth metals and Fe in coal, and slow down the slagging phenomenon of boilers burning high-alkali coal; Step 5. Reasonable coal blending: By blending high-alkali coal with low-alkali coal, the content of alkali metals in the mixed coal can be reduced so that the quality of the blended coal meets the requirements of boiler combustion. It is necessary to determine the target characteristics of the mixed coal, conduct index analysis on the Tianchi energy mixed coal and coal gangue to be used, provide raw coal industrial analysis, ash component analysis and ash viscosity analysis data, including key indicators such as calorific value, volatile matter, sulfur content, ash content, etc., and adjust the boiler design and operation parameters; Step 6: Keep the heating surface clean: Keep the heating surface clean by treating the heat exchange surface, optimizing the boiler design and adjusting the operating conditions, and inhibit the condensation of alkali metals on the heating surface and the adhesion of fine particles on the heating surface; Step 7: Blending low-alkali coal: Blending low-alkali coal can reduce the formation of liquid AAEM sulfate; Step 8: Liquid slag discharge process: The liquid slag discharge process can effectively capture the alkali metals in the high-alkali coal, and discharge the low-temperature eutectic such as Na-Ca-Fe-Al-Si from the furnace in the form of liquid slag, thereby reducing the total amount of alkali metals near the subsequent heating surface and realizing the modification of fly ash; Step 9, gasification test: Carry out gasification tests of high alkali metal and alkaline earth metal coal under different atmospheres, analyze the liquid phase growth law of ash slag by combining phase equilibrium calculation, and analyze the influence of coal ash component changes on ash fusibility through phase diagram; Step 10: Control of coal ash components: By adjusting the relative contents of components such as SiO2, Al2O3, Na2O and CaO in the coal ash, the ash fusibility can be effectively controlled to prevent slagging.

2. A method for slagging high-alkali metal coal according to claim 1, characterized in that: The step three also includes an ash melting temperature test, which is performed by using an ash melting temperature tester, a thermomechanical analyzer, a thermogravimetric-differential scanning calorimeter and other equipment to explore the slagging tendency and slagging process of high-alkali coal ash slag.

3. A method for slagging high-alkali metal coal according to claim 1, characterized in that: The step seven also includes studying the effects of different coal blending ratios and steam soot blowing on the furnace outlet temperature and temperature rise, and calculating the furnace soot blowing operation time interval based on the furnace outlet temperature to control the burning ratio.

4. A method for slagging high-alkali metal coal according to claim 1, characterized in that: The reasonable coal blending in step five includes determining the coal blending target, determining the target indicators of coal blending, such as calorific value, volatile matter, ash content, and sulfur content, according to the requirements of the boiler or coke oven; coal quality analysis, conducting detailed coal quality analysis on various coals involved in coal blending, including ash content, volatile matter, sulfur content, moisture content, and calorific value; coal type selection, selecting appropriate coal types for blending according to the coal blending target and coal quality analysis results, including selecting coal types with low ash content and low sulfur content to reduce pollutant emissions, or selecting coal types with high volatile content to improve combustion efficiency; coal blending ratio calculation; coal blending test; adjustment and optimization; and real-time monitoring.

5. A method for slagging high-alkali metal coal according to claim 1, characterized in that: The analysis method in step one includes an extraction method, and the specific steps are: water-soluble extraction; ammonium acetate-soluble extraction; hydrochloric acid-soluble extraction and insoluble extraction; low-temperature ashing method, ashing the coal sample under low-temperature conditions to reduce the release of alkali metals, thereby obtaining a more accurate measurement value.

6. A method for slagging high-alkali metal coal according to claim 1, characterized in that: The step five also includes collecting characteristic data of each single type of coal; calculating the mixing ratio: based on the target characteristics and the data of the single type of coal, accurately measuring the weight of the coal and calculating the mixing ratio; sampling and testing, trial burning, adjusting parameters according to the results, and finally determining the coal ratio; specifically including: collecting characteristic data of each single type of coal includes sampling coal, analyzing the moisture, ash, volatile matter, sulfur content, and calorific value of the collected different coals, collating the analyzed data, establishing a database, analyzing and statistics the data in the database to obtain the distribution and correlation information of the characteristic parameters of the coal; calculating the mixing ratio specifically includes determining the target characteristics, clarifying the expected characteristics of the mixed coal, such as calorific value, volatile matter, sulfur content, ash content, and collecting data of the single type of coal.

7. A method for slagging high-alkali metal coal according to claim 1, characterized in that: The blending of low-alkali coal in step seven also includes conducting combustion tests to verify the feasibility of the blending ratio and the combustion effect; boiler design adjustment, according to the coal quality characteristics after blending, it may be necessary to adjust the boiler design to adapt to the new coal characteristics. During the blending process, it is necessary to optimize the boiler operating parameters. At the same time, during the blending process, the operating conditions of the boiler are closely monitored, including exhaust gas temperature, plant power consumption rate, boiler combustion stability, boiler efficiency, and the impact of blending low-alkali coal on environmental protection is evaluated, including the emissions of sulfur dioxide (SOx), nitrogen oxides (NOx), carbon monoxide (CO), organic compounds and dust particles.

8. A method for slagging high-alkali metal coal according to claim 1, characterized in that: The liquid slag discharge process in step eight specifically includes high-temperature combustion; melting slag, using high temperature to melt the coal ash into liquid slag and discharge it out of the furnace; using a slag discharge system for slag discharge, the slag discharge system includes a lower slag slurry pump for discharging the molten slag from the bottom of the furnace; granulation treatment, through granulation treatment, it is converted into fine particles for subsequent processing and utilization; waste heat recovery; slag particle cooling.

9. A method for slagging high-alkali metal coal according to claim 1, characterized in that: The gasification test in step nine specifically includes test design: selecting a suitable experimental method according to needs; fuel preparation, including pretreatment of the fuel; gasification agent selection, selecting a suitable gasification agent, such as air, oxygen, water vapor or a mixture thereof; test parameter setting, test operation; data collection; product analysis; and result evaluation.

10. A method for slagging high-alkali metal coal according to claim 1, characterized in that: The control of the ash components in step ten specifically includes: extracting useful components from fly ash using mineral processing and separation technology; effectively controlling the ash fusibility by adjusting the relative contents of components such as SiO2, Al2O3, Na2O and CaO in the ash; and combining reasonable coal blending to mix low-melting-point coal with high-melting-point coal to increase the ash melting point of the mixed coal.

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