Preparation of power plant flue gas high adsorption performance cementing material from mine solid waste and preparation method thereof

Abstract

The application discloses a kind of mine solid waste directional dissociation preparation power plant flue gas high adsorption performance cementing material and its preparation method, comprising the following steps: 1) based on the key component content of each narrow particle size of coal gangue determined by directional dissociation technology, the corresponding relationship model of key component and particle size distribution is constructed;2) with different particle size of coal gangue, fly ash and cement as dry material and water mixture to prepare cementing material.3) through laboratory test, the influence law of gangue particle size gradation and filling material ratio on the performance of cementing material is studied;4) according to the composition of coal mine power plant flue gas composition, the corresponding optimal ratio is obtained;5) the selective crushing of coal gangue is carried out by using multi-layer gradient variable-pore-size screening equipment, and the mixed particle size coal gangue material required is accurately prepared, and then the material preparation is carried out.The method can optimize the adsorption performance of cementing material to power plant flue gas, which is beneficial to the collaborative treatment of power plant flue gas and mine solid waste underground.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of mine solid waste directional dissociation preparation power plant flue gas high adsorption performance cementing material and preparation method thereof, belong to power plant flue gas processing technical field. BACKGROUND

[0002] China's energy supply will continue to rely on coal resources, most of the coal mined from underground is transported to coal-fired power plants for energy conversion and utilization, which inevitably produces a large amount of power plant flue gas. Power plant flue gas is mainly composed of carbon dioxide, sulfur dioxide and nitrogen, and the main treatment method is to discharge it into the atmosphere after desulfurization. The demand for emission reduction is urgent. At the same time, the pollution caused by the accumulation of mine solid waste cannot be ignored.

[0003] Currently, geological storage technology has broad development prospects in the field of coal mine treatment of harmful gases. This technology mainly achieves the purpose of effective emission reduction by causing mineralization reaction between gas and cementing material. The adsorption performance between cementing material and gas is an important factor affecting the efficiency of gas treatment. However, the enrichment of effective components in the current cementing material for flue gas reaction is poor, which limits the efficiency of flue gas storage. Therefore, it is of great significance to develop a kind of cementing material with high adsorption performance for power plant flue gas using mine solid waste as the main material for low-cost and high-efficiency treatment and utilization of solid waste and flue gas. SUMMARY

[0004] To solve the problems of the prior art, the present application aims to provide a kind of mine solid waste directional dissociation preparation power plant flue gas high adsorption performance cementing material and preparation method thereof, to further enrich the efficient treatment way of power plant flue gas.

[0005] To achieve the above-mentioned goal, the present application adopts the following technical solution:

[0006] The first object of the present application is to provide a kind of mine solid waste directional dissociation preparation power plant flue gas high adsorption performance cementing material, which is prepared by mixing dry materials with water, wherein the dry materials include mixed particle size coal gangue, fly ash and cement, the large particle size gangue is composed of large particle size gangue and narrow particle size gangue, and the narrow particle size gangue is graded coal gangue with different particle sizes of 0-3 mm.

[0007] Optionally, in one embodiment of the present application, the narrow particle size gangue is graded coal gangue with different particle sizes prepared by directional crushing and dissociation of mine solid waste.

[0008] Optionally, in an embodiment of the present application, the narrow particle size gangue is composed of classified coal gangue with particle sizes of (0-0.5mm), (0.5-1.0mm), (1.0-2.0mm), (2.0-3.0mm). Preferably, the narrow particle size gangue is composed of classified coal gangue with particle sizes of 0.5mm, 1.5mm, 2mm, 2.5mm, 3mm; in other examples of the present application, it can also be other arbitrary values of particle size of 0-3mm, such as 0.6mm, 0.8mm, 1.05mm, 1.3mm, 1.9mm, 2.41mm, 2.75mm, 2.93mm, etc., all of which are not limited.

[0009] Further optionally, in an embodiment of the present application, the narrow particle size gangue is composed of classified coal gangue with particle sizes of (0-0.5mm), (0.5-1.0mm), (1.0-2.0mm), (2.0-3.0mm) in a mass ratio of 1-3:1-3:0.5-1:5-8. Preferably, the narrow particle size gangue is composed of classified coal gangue with particle sizes of (0-0.5mm), (0.5-1.0mm), (1.0-2.0mm), (2.0-3.0mm) in a mass ratio of 2:2:1:5.

[0010] Optionally, in an embodiment of the present application, in the second step, the particle size of the large particle size gangue is 3mm-10mm. The large particle size gangue in the present application is gangue with particle sizes of 3mm-10mm, such as 3mm, 3.5mm, 4.4mm, 5.2mm, 57mm, 6.1mm, 7.5mm, 8.2mm, 9.1mm, 10mm, etc., all of which are not limited in the present application.

[0011] Optionally, in an embodiment of the present application, the mass ratio of the large particle size gangue, the narrow particle size gangue, fly ash, and cement is 10-30:10-30:20-30:15-20.

[0012] Optionally, in an embodiment of the present application, the cementitious material satisfies at least one of the following: slump of 220-260mm, initial setting time less than 4 hours, final setting time not greater than 24 hours, early compressive strength greater than 1MPa, later compressive strength not less than 4MPa, decarburization rate and desulfurization rate greater than 98%.

[0013] A second object of the present application is to provide a method for preparing a power plant flue gas high-adsorption performance cementitious material from mine solid waste directional dissociation, comprising the following steps:

[0014] The first step is to break the coal gangue into narrow particle size fractions based on the directional dissociation technology, and analyze the key component content of each narrow particle size fraction to construct a corresponding relationship model between the key component and the particle size distribution.

[0015] The second step is to prepare a cementitious material using large particle size gangue, narrow particle size gangue after directional dissociation, fly ash, and cement as raw materials. The large particle size gangue can increase the porosity of the cementitious material, thereby improving the flue gas adsorption capacity of the cementitious material.

[0016] The third step is to conduct laboratory tests to evaluate the transport performance (i.e., the fluidity of the filling material), mechanical properties, and flue gas sealing performance of the cementitious material as evaluation indexes, and to study the influence of particle size distribution, filling material concentration, flue gas concentration, flue gas injection amount, and flue gas injection time on the evaluation indexes.

[0017] The fourth step is to analyze the composition of coal mine flue gas and determine the optimal ratio of high adsorption performance cementitious material corresponding to different gas adsorption requirements.

[0018] The fifth step is to prepare a high adsorption performance cementitious material according to the optimal ratio of the cementitious material.

[0019] Optionally, in one embodiment of the present application, the preparation method of the high adsorption performance cementitious material of the fifth step includes the following steps:

[0020] a. According to the optimal ratio of large particle size gangue and narrow particle size gangue after directional dissociation, use a grading screen to selectively crush the coal gangue to accurately prepare the mixed particle size coal gangue material required; wherein the grading screen can be any existing device, and in some embodiments of the present application, the grading screen can refer to the content disclosed in the existing patent, patent name: Coal gangue grading intelligent sorting device, patent number: ZL202220490049.X.

[0021] b. Add the prepared large particle size gangue and narrow particle size gangue after directional dissociation to the high adsorption performance cementitious material mold;

[0022] c. Mix the fly ash and cement with water to form a slurry, and pour the slurry from the top of the mold through the pouring hole until the mold is filled;

[0023] d. Open the bottom slurry discharge hole of the mold to discharge excess fly ash and cement slurry;

[0024] e. Place the sample in a curing box for curing, and the high adsorption performance cementitious material is obtained.

[0025] Optionally, in an embodiment of the present application, the directional crushing dissociation technology in the first step is crushing dissociation, specifically comprising: crushing the coal gangue into different narrow particle size gangues using at least one crushing device such as a crusher, a ball mill, etc., and determining the physical characteristics thereof by means of laboratory XRD, etc., wherein the physical characteristics include key components and contents of the narrow particle size gangues in different particle size ranges, thereby obtaining a corresponding relationship between the narrow particle size gangues in different particle sizes and the contents of the key components.

[0026] Optionally, in an embodiment of the present application, according to the power plant flue gas treatment requirements, the key components of the narrow particle size gangue include alkali metal active components, and the alkali metal active components include MgO and CaO.

[0027] Optionally, in an embodiment of the present application, the particle size of the narrow particle size gangue is 0-3 mm.

[0028] Optionally, in an embodiment of the present application, in the second step, the particle size of the large particle size gangue is 3-10 mm.

[0029] Optionally, in an embodiment of the present application, the mass ratio of the large particle size gangue, the narrow particle size gangue, the fly ash and the cement is 10-30:10-30:20-30:15-20.

[0030] Optionally, in an embodiment of the present application, the evaluation indexes of the cementitious material conveying performance in the third step include the slump, the initial and final setting times, the evaluation indexes of the mechanical properties include the early and later compressive strengths, and the evaluation indexes of the power plant flue gas sealing performance include the decarburization rate and the desulfurization rate.

[0031] Optionally, in an embodiment of the present application, the decarburization rate and the desulfurization rate can be calculated by measuring the volume fractions of CO2 and SO2 in the gas before and after adsorption in the laboratory, and the specific calculation formulae are as follows:

[0032]

[0033]

[0034] In the formula, T CO2 is the decarburization rate, %; CO0 is the initial volume fraction of CO2; CO1 is the CO2 volume fraction after the adsorption test; T SO2 is the decarburization rate, %; SO0 is the initial volume fraction of SO2; SO1 is the SO2 volume fraction after the adsorption test;

[0035] Optionally, in one embodiment of the present application, the optimal ratio selection in the fourth step is evaluated by the following criteria: the coal gangue with high flue gas adsorption performance is preferred to have large particle size, good conveying performance and mechanical properties, and high decarburization and desulfurization rates, wherein the slump is between 220 and 260 mm, the initial setting time is less than 4 hours, the final setting time is not greater than 24 hours, the early compressive strength is greater than 1 MPa, the late compressive strength is not less than 4 MPa, and the decarburization and desulfurization rates are greater than 98%.

[0036] Optionally, in one embodiment of the present application, the multi-layer gradient variable aperture screening device in the fifth step needs to be able to realize the gradient screening of coal gangue with a specific particle size range, and through the use of the movement and transformation of the baffle position, the collection of multi-gradient and multi- latitude segmented products is realized, so as to achieve the purpose of directional pre-enrichment of alkali metal oxides in coal gangue.

[0037] The present application has the following beneficial effects: the present method proposes to use directional dissociation technology to process coal gangue, and through the use of equipment capable of accurately screening effective components, the pre-enrichment of effective components of coal gangue is realized, and the reaction area of the dissociated coal gangue is increased, which helps to improve the reaction speed. The high adsorption performance cementing material for flue gas of the present method provides an efficient treatment method for flue gas of power plants, which is conducive to the harmless treatment of coal mine power plant flue gas, expands the comprehensive utilization method of mine solid waste, and promotes the realization of green mine construction. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 is a flowchart of the present method.

[0039] Figure 2 is a schematic diagram of the structure and size of the preparation mold of the high adsorption performance cementing material of the present application, wherein (a) is a schematic diagram of the overall structure of the preparation mold, and (b) is a top view of the bottom of the mold.

[0040] Figure 3 is a corresponding relationship between the key component content and the narrow particle size gangue of different particle sizes in one embodiment of the present application.

[0041] In the figure, 1 is a top grouting hole, 2 is a mold top, 3 is a mold outer wall, 4 is a high adsorption performance cementing material preparation mold, 5 is a bottom grouting hole, and 6 is a mold bottom. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be described clearly and completely in the following in combination with the drawings in the embodiments of the present application and the description of the content of the invention, and the embodiments will be described in combination with the engineering geological conditions of a certain coal mine.

[0043] EMBODIMENT

[0044] The embodiment of the application aims at the problem of harmless treatment of coal mine flue gas, and the current situation that the adsorption performance of existing cementitious materials is low, and provides a method for preparing cementitious materials with high adsorption performance for power plant flue gas from mine solid waste directional dissociation, and the specific steps are as follows:

[0045] Firstly, narrow particle size gangue is obtained based on the directional dissociation technology, and the content of key components of each narrow particle size gangue is analyzed to construct a corresponding relationship model of key components and particle size distribution.

[0046] Secondly, cementitious materials are prepared from large particle size gangue, narrow particle size gangue after directional dissociation, fly ash and cement as raw materials. The coal gangue with large particle size can increase the porosity of the cementitious material, thereby improving the flue gas adsorption capacity of the cementitious material.

[0047] Thirdly, through laboratory tests, the influence of factors on evaluation indexes is studied, taking the conveying performance (i.e. the fluidity of filling material), mechanical properties (such as strength) and power plant flue gas sealing performance of the cementitious material as evaluation indexes, and taking the particle size grading of large particle size gangue and narrow particle size gangue after directional dissociation, the concentration of filling material, the concentration of flue gas, the injection amount of flue gas and the injection time of flue gas as influencing factors.

[0048] Fourthly, the composition of coal mine power plant flue gas is analyzed, and different proportioning conditions are obtained according to different gas adsorption requirements, and the corresponding evaluation index results are obtained, and the optimal proportioning of the corresponding cementitious material with high adsorption performance is obtained by comprehensively considering various evaluation standards.

[0049] Fifthly, the preparation method of cementitious material with high adsorption performance comprises the following steps:

[0050] a. According to the optimal grading of large particle size gangue and narrow particle size gangue after directional dissociation in the optimal proportioning, the multi-layer stepped variable-pore-size screening equipment is used for selective crushing of coal gangue to accurately prepare the mixed particle size coal gangue material required;

[0051] b. The prepared large particle size gangue and narrow particle size gangue after directional dissociation are added to the high adsorption performance cementitious material mold 4;

[0052] c. The fly ash and cement are mixed with water to form a slurry, and the slurry is poured into the high adsorption performance cementitious material mold 4 from the top pouring hole 1 of the mold;

[0053] d. The bottom slurry discharge hole 5 arranged at the bottom of the mold 6 is opened, and the excess fly ash and cement slurry is discharged;

[0054] e. After the sample is placed in a curing box for curing, the cementitious material with high adsorption performance is obtained, and the conveying performance, mechanical strength and power plant flue gas sealing performance of the obtained cementitious material are tested.

[0055] In the present embodiment, the raw coal gangue used is large particle size coal gangue, and the main component proportions of the coal gangue are shown in Table 1.

[0056] Table 1 Main component proportions of coal gangue

[0057]

[0058] Specifically, in the present embodiment, the directional dissociation technique in the first step is crushing dissociation, and a crushing device such as a crusher or a ball mill is used to crush the coal gangue into different narrow particle size gangues with particle sizes of 0.5 mm, 1.5 mm, 2 mm, 2.5 mm, and 3 mm. The key components in different particle size ranges are determined by laboratory XRD analysis, and thus the corresponding relationship between the narrow particle size gangues in different particle sizes and the content of the key components is obtained.

[0059] In the present embodiment, according to the requirements of power plant flue gas treatment, the key components in the narrow particle size gangue are mainly alkali metal active components, wherein the alkali metal active components are MgO and CaO, and the chemical component contents are shown in Table 2 below.

[0060] Table 2 Chemical component contents of alkali metal active components

[0061]

[0062] Specifically, in the present embodiment, in the second step, the particle size of the large particle size gangue is 3 mm to 10 mm.

[0063] By using the chemical component contents and particle size distribution of the alkali metal active components obtained above as input data, and through data fitting by minitab analysis software, the corresponding relationship between the narrow particle size gangues in different particle sizes and the content of the key components is obtained as shown in Table 3. Figure 3

[0064] Specifically, in the present embodiment, the evaluation indexes of the cementitious material delivery performance in the third step are slump, initial setting time, and final setting time, and the evaluation indexes of the mechanical properties are early and later compressive strength, and the evaluation indexes of the power plant flue gas sealing performance are decarburization rate and desulfurization rate. Among them, the slump is tested by the chute method using a slump barrel, and the initial setting time and the final setting time are obtained by the Vicat method, and the early and later compressive strength can be obtained by the compression test method of the press.

[0065] Specifically, in the present embodiment, the decarburization rate and the desulfurization rate can be calculated by measuring the volume fractions of CO2 and SO2 in the gas before and after adsorption in the laboratory, and the specific calculation formula is:

[0066]

[0067] ​

[0068] wherein T CO2 is the decarburization rate, %; C0is the initial volume fraction of CO2; C1is the volume fraction of CO2after the adsorption test; T SO2 is the decarburization rate, %; S0is the initial volume fraction of SO2; S1is the volume fraction of SO2after the adsorption test.

[0069] Specifically, in this embodiment, when the optimal ratio selection is performed, the mine pressure appearance of the coal mine is obvious, and the underground filling material needs to select a ratio with a higher flue gas adsorption rate on the basis of ensuring the strength. The mass ratio of the narrow particle size gangue particle size selected in this embodiment is (0-0.5 mm):(0.5-1.0 mm):(1.0-2.0 mm):(2.0-3.0 mm)=2:2:1:5. The filling material concentration is 74%, and the mass ratio of the large particle size gangue, the narrow particle size gangue, the fly ash, and the cement is 2:3:3:2. Under the optimal ratio condition, the test results in this embodiment are shown in the following table, which meets the evaluation standard that the power plant flue gas high adsorption performance cementitious material is preferred to have a large gangue particle size, good conveying performance and mechanical properties, and high decarburization and desulfurization rates.

[0070] Table 3 Test results of performance indicators of cementitious materials

[0071]

[0072] Specifically, in this embodiment, the influencing factors of the cementitious material obtained in step three have the following influence law on the evaluation indicators: the larger the gangue particle size, the higher the mechanical properties and the power plant flue gas sealing performance, and the conveying performance is not greatly affected; the higher the filling material concentration, the worse the conveying performance, and the higher the mechanical properties and the power plant flue gas sealing performance; the larger the flue gas concentration, the flue gas injection amount, and the flue gas injection time indicators, the conveying performance and the mechanical properties are not greatly affected, and the power plant flue gas sealing performance first increases and then remains unchanged.

[0073] Specifically, in this embodiment, the grading screen in the fifth step needs to be able to realize the grading screening of coal gangue with a specific particle size range. By using the movement transformation of the baffle position, the collection of multi-gradient and multi- latitude segmented products is realized, so as to achieve the purpose of directional pre-enrichment of alkali metal oxides in coal gangue. In this embodiment, the grading screen can refer to the existing disclosed content in the patent, and the patent name is: a coal gangue grading intelligent sorting device, and the patent number is: ZL202220490049.X.

[0074] Specifically, in the embodiment, a kind of power plant flue gas high adsorption performance cementing material prepared by mine solid waste directional dissociation is finally obtained, the cementing material is prepared by mixing dry material with water, wherein the dry material includes mixed particle size coal gangue, fly ash, cement, the large particle size gangue is composed of large particle size gangue and narrow particle size gangue, and the narrow particle size gangue is different particle size graded coal gangue prepared by mine solid waste directional crushing dissociation.In the embodiment, the equipment used for directional crushing dissociation is the aforementioned grading screening machine.

[0075] Obviously, the described embodiments are only part of the embodiments of the present application, not all. For ordinary skilled in the art, without departing from the principles of the present application, can also make a number of improvements and refinements, which should be considered as part of the authorized description.

Claims

1. A power plant flue gas high-adsorption performance cementing material prepared by directional dissociation of mine solid waste, characterized in that, The cementing material is prepared by mixing dry materials with water, wherein the dry materials include mixed particle size coal gangue, fly ash and cement, the mixed particle size coal gangue is composed of large particle size gangue and narrow particle size gangue, the particle size of the large particle size gangue is 3mm-10mm, the narrow particle size gangue is composed of classified coal gangue with particle sizes of (0-0.5mm), (0.5-1.0mm), (1.0-2.0mm) and (2.0-3.0mm) in a mass ratio of 1-3:1-3:0.5-1:5-8, and the mass ratio of the large particle size gangue, the narrow particle size gangue, the fly ash and the cement is 10-30:10-30:20-30:15-20. The power plant flue gas high adsorption performance cementing material meets at least one of the following: a slump of 220-260mm, an initial setting time of less than 4 hours, a final setting time of not more than 24 hours, an early compressive strength of more than 1MPa, a later compressive strength of not less than 4MPa, and a decarburization rate and a desulfurization rate of more than 98%. The method for preparing the power plant flue gas high adsorption performance cementing material from the mine solid waste directional dissociation includes the following steps: Step 1: obtaining the narrow particle size gangue based on the directional crushing dissociation technology, and analyzing the key component content of each narrow particle size gangue to construct a corresponding relationship model of the key components and the particle size distribution; Step 2: preparing the cementing material with the large particle size gangue, the narrow particle size gangue, the fly ash and the cement as raw materials; Step 3: through laboratory tests, taking the conveying performance, the mechanical properties and the power plant flue gas sealing performance of the cementing material as evaluation indexes, and taking the particle size grading of the large particle size gangue and the narrow particle size gangue, the filling material concentration, the flue gas concentration, the flue gas injection amount and the flue gas injection time as influencing factors, the influence law of the influencing factors on the evaluation indexes is studied; Step 4: analyzing the composition of the coal mine power plant flue gas, and obtaining the corresponding optimal proportion of the high adsorption performance cementing material according to different gas adsorption requirements; Step 5: preparing the power plant flue gas high adsorption performance cementing material according to the optimal proportion of the cementing material.

2. The power plant flue gas high-adsorption performance cementing material prepared by the directional dissociation of mine solid waste according to claim 1, characterized in that, The narrow particle size gangue is composed of classified coal gangue with particle sizes of (0-0.5mm), (0.5-1.0mm), (1.0-2.0mm) and (2.0-3.0mm) in a mass ratio of 2:2:1:

5.

3. The power plant flue gas high-adsorption performance cementing material prepared by the directional dissociation of mine solid waste according to claim 1, characterized in that, The mass ratio of the large particle size gangue, the narrow particle size gangue, the fly ash and the cement is 2:3:3:

2.

4. The mine solid waste directional dissociation preparation of power plant flue gas high adsorption performance cementing material according to claim 2, characterized in that, The preparation method of the power plant flue gas high adsorption performance cementing material in Step 5 includes the following steps: a. according to the optimal grading of the large particle size gangue and the narrow particle size gangue after directional dissociation in the optimal proportion, the coal gangue is selectively crushed by using a multi-layer stepped variable-pore-size screening device to accurately prepare the mixed particle size coal gangue material required; b. adding the prepared large particle size gangue and narrow particle size gangue into the high adsorption performance cementing material mold; c. mixing the fly ash and the cement with water to prepare a slurry, and pouring the slurry into the mold from the top pouring hole until the mold is filled; d. opening the bottom slurry discharge hole of the mold to discharge the excess fly ash and cement slurry; e. placing the sample in a curing box for curing, and the high adsorption performance cementing material is obtained.

5. The mine solid waste directional dissociation preparation of power plant flue gas high adsorption performance cementing material according to claim 1, characterized in that, The directional crushing dissociation technology in the first step specifically comprises: crushing coal gangue into different narrow particle size gangue using a crushing device, analyzing physical characteristics of the gangue, the physical characteristics including key components and contents of the key components of the narrow particle size gangue in different particle size ranges, thereby obtaining a corresponding relationship between the narrow particle size gangue in different particle sizes and the contents of the key components; The crushing device comprises at least one of a crusher and a ball mill; The analysis means of the physical characteristics comprises XRD; The key components of the narrow particle size gangue comprise alkali active components, the alkali active components comprising MgO and CaO.

6. The mine solid waste directional dissociation preparation of power plant flue gas high adsorption performance cementing material according to claim 1, characterized in that, The evaluation indexes of the cementing material conveying performance in the third step include slump, initial setting time and final setting time, the mechanical performance evaluation indexes include early and late compressive strength, and the power plant flue gas sealing performance evaluation indexes include decarburization rate and desulfurization rate.

7. The mine solid waste directional dissociation preparation of power plant flue gas high adsorption performance cementing material according to claim 6, characterized in that, The decarburization rate and the desulfurization rate are respectively measured in a laboratory, and the volume fractions of CO2 and SO2 in the gas before and after adsorption are calculated, and the specific calculation formula is: wherein T CO2 is the decarburization rate, %; C0is the initial volume fraction of CO2; C1is the volume fraction of CO2after the adsorption test; T SO2 is the desulfurization rate, %; S0is the initial volume fraction of SO2; S1is the volume fraction of SO2after the adsorption test.

8. The mine solid waste directional dissociation preparation of power plant flue gas high adsorption performance cementing material according to claim 1, characterized in that, When the optimal proportioning is selected in the fourth step, the evaluation criteria are: the slump is 220-260 mm, the initial setting time is less than 4 hours, the final setting time is not greater than 24 hours, the early compressive strength is greater than 1 MPa, the late compressive strength is not less than 4 MPa, and the decarburization rate and the desulfurization rate are greater than 98%.

9. The mine solid waste directional dissociation preparation of power plant flue gas high adsorption performance cementing material according to claim 4, characterized in that, The multi-layer gradient variable-pore-size screening device in the fifth step realizes the collection of multi-gradient and multi- latitude segmented products by using the movement and transformation of the baffle position, and achieves the purpose of directional pre-enrichment of alkali metal oxides in coal gangue.

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