Coal dressing foaming agent, preparation method thereof and coal flotation method

Abstract

The invention provides a coal dressing foaming agent, a preparation method thereof and a coal flotation method, and relates to the field of coal dressing foaming agents. The coal dressing foaming agent is prepared from the following raw materials in parts by weight: 40 to 50 parts of triethyl phosphate, 12 to 25 parts of 2-methylthiobenzothiazole, 12 to 23 parts of triethylamine, 12 to 20 parts of alcohol compound and 1 to 5 parts of emulsifier. According to the coal dressing foaming agent, bubbles in a water layer in a bubble film can be stabilized, the water layer in the bubble film can be kept due to the high hydration capacity, the proper hydration capacity is achieved, foams with the proper stability can be generated, the foaming agent can generate the foams with the proper size and the certain stability to enable particles to smoothly float up, and the foaming effect is good. And meanwhile, the three-phase foam can be automatically broken without influencing the subsequent flotation process, has higher foaming performance, is safe and environment-friendly, and can reduce the ash content of the clean coal while improving the yield of the clean coal compared with a conventional alcohol reagent.

Description

Technical Field

[0001] The present application relates to the field of coal preparation, and in particular to a coal preparation frother and a preparation method thereof and a coal flotation method. Background Art

[0002] With the continuous development of science and technology, less and less attention is paid to removing coal slime in raw coal during coal extraction, which leads to the reduction of coal quality. With the requirements of users and all aspects of society for improving the quality of clean coal, the role of flotation in coal preparation becomes particularly important.

[0003] In the flotation process, it is often necessary to add flotation agents to change the hydrophobicity of the coal surface, improve the floatability of the coal, and achieve effective separation of coal and gangue. However, in the prior art, single 2-octanol is used as a frother in coal slime flotation, which has the problems of large agent consumption, general flotation effect, and difficult to break foam in the discharged tailings water. Summary of the invention

[0004] The purpose of the present application is to provide a coal preparation frother and a preparation method thereof and a coal flotation method to solve the above problems.

[0005] In order to achieve the above objectives, the first aspect of the present application provides a coal preparation foaming agent, the raw materials of which, in parts, include:

[0006] 40-50 parts of triethyl phosphate, 12-25 parts of 2-methylthiobenzothiazole, 12-23 parts of triethylamine, 12-20 parts of alcohol compounds, and 1-5 parts of emulsifier.

[0007] Optionally, the raw materials of the coal preparation foaming agent, calculated as 100% by total mass, include:

[0008] 42-48 parts of triethyl phosphate, 15-23 parts of 2-methylthiobenzothiazole, 15-20 parts of triethylamine, 15-18 parts of alcohol compounds, and 1-4 parts of emulsifier.

[0009] Optionally, the raw materials of the coal preparation foaming agent, calculated as 100% by total mass, include:

[0010] 42-48 parts of triethyl phosphate, 15-23 parts of 2-methylthiobenzothiazole, 16-18 parts of triethylamine, 15-17 parts of alcohol compound, and 2-4 parts of emulsifier.

[0011] Optionally, the alcohol compound includes one or more of methanol, ethanol, and isopropanol.

[0012] Optionally, the emulsifier includes Span 80.

[0013] The second aspect of the present application provides a method for preparing the coal preparation foaming agent, comprising:

[0014] The raw materials are mixed.

[0015] Optionally, the mixing includes:

[0016] The triethyl phosphate and part of the alcohol compound are first mixed to obtain a solution A;

[0017] The 2-methylthiobenzothiazole and the remaining alcohol compound are mixed for a second time to obtain a solution B;

[0018] Mixing the solution A and the solution B for the third time to obtain a solution C;

[0019] The solution C, triethylamine and emulsifier are mixed for the fourth time.

[0020] The third aspect of the present application provides a coal flotation method, comprising:

[0021] The raw coal ore is slurried to obtain slurry;

[0022] The ore pulp, the coal preparation frother or the coal preparation frother prepared by the preparation method of the coal preparation frother, and a collector are mixed, and clean coal is obtained by flotation.

[0023] Optionally, the coal flotation method satisfies at least one of the following conditions:

[0024] A. The concentration of the ore pulp is 80g / L-100g / L of raw ore;

[0025] B. The dosage of the collector is 3kg / t-4kg / t of raw ore;

[0026] C. The collector includes diesel.

[0027] Optionally, the amount of the coal preparation foaming agent used is 125g / t-150g / t-ore.

[0028] Compared with the prior art, the beneficial effects of this application include:

[0029] The coal preparation foaming agent provided in the present application can stabilize the bubbles in the water layer in the bubble film, and its strong hydration ability can maintain the water layer in the bubble film. It has both appropriate hydration ability and can produce foam with appropriate stability. The foaming agent can produce foam of appropriate size and certain stability to float the particles smoothly. At the same time, the three-phase foam can burst autonomously without affecting the subsequent flotation process. It has strong foaming performance and is safe and environmentally friendly. Compared with conventional alcohol agents, it can increase the yield of clean coal while reducing the ash content of clean coal.

[0030] The preparation method of the coal preparation foaming agent provided in the present application has a simple preparation process. The raw materials of the foaming agent are from a wide range, and the flash points of the main components are higher than the national standard range. An intermediate product with stable properties can be obtained through the intermediate product synthesis path. The intermediate product can be used as a raw material for compound synthesis and as a raw material for other products.

[0031] The coal flotation method provided in the present application reduces reagent consumption while improving both the flotation yield and the ash content, and has good economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope of the present application.

[0033] Figure 1 The infrared spectrum of the coal preparation foaming agent provided in Example 1;

[0034] Figure 2 This is a physical picture of the slurry flotation provided in Example 1. DETAILED DESCRIPTION

[0035] As used herein:

[0036] "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0037] The conjunction "consisting of excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed-ended so that it does not include materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim rather than immediately following the subject matter, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0038] When an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values ​​and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed separately. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted as including ranges "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described in this article, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0039] In these examples, parts and percentages are by mass unless otherwise indicated.

[0040] "Parts by mass" refers to the basic unit of measurement for expressing the mass ratio of multiple components. 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass of component A is a parts and the mass of component B is b parts, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it means that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, indicating a multiple factor). It should not be misunderstood that, unlike the mass parts, the sum of the mass of all components is not limited to 100 parts.

[0041] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0042] The first aspect of the present application provides a coal preparation foaming agent, the raw materials of which, in parts, include:

[0043] 40-50 parts of triethyl phosphate, 12-25 parts of 2-methylthiobenzothiazole, 12-23 parts of triethylamine, 12-20 parts of alcohol compound, and 1-5 parts of emulsifier.

[0044] Optionally, the raw materials of the coal preparation foaming agent are calculated in parts: triethyl phosphate can be 40 parts, 45 parts, 50 parts or any value between 40 parts and 50 parts, 2-methylthiobenzothiazole can be 12 parts, 20 parts, 25 parts or any value between 12 parts and 25 parts, triethylamine can be 12 parts, 20 parts, 23 parts or any value between 12 parts and 23 parts, the alcohol compound can be 12 parts, 15 parts, 20 parts or any value between 12 parts and 20 parts, and the emulsifier can be 1 part, 3 parts, 5 parts or any value between 1 part and 5 parts.

[0045] In some embodiments, the raw materials of the coal preparation foaming agent, calculated as 100% by total mass, include:

[0046] 42-48 parts of triethyl phosphate, 15-23 parts of 2-methylthiobenzothiazole, 15-20 parts of triethylamine, 15-18 parts of alcohol compounds, and 1-4 parts of emulsifier.

[0047] Optionally, the raw materials of the coal preparation foaming agent are calculated in parts: triethyl phosphate can be 42 parts, 44 parts, 46 parts, 48 ​​parts or any value between 42 parts and 48 parts, 2-methylthiobenzothiazole can be 15 parts, 17 parts, 19 parts, 21 parts, 23 parts or any value between 15 parts and 23 parts, triethylamine can be 15 parts, 17 parts, 19 parts, 20 parts or any value between 15 parts and 20 parts, the alcohol compound can be 15 parts, 16 parts, 18 parts or any value between 15 parts and 18 parts, and the emulsifier can be 1 part, 2 parts, 3 parts, 4 parts or any value between 1 part and 4 parts.

[0048] It should be noted that the reason for further optimizing the dosage ratio is that the intermediate dissolution prepared in steps can be more complete and the flash point of the synthetic product can reach a higher value, ultimately obtaining an efficient and environmentally friendly foaming agent for coal preparation. The foaming properties are not affected while reducing the proportion of raw materials in the preparation of the agent.

[0049] In some embodiments, the raw materials of the coal preparation foaming agent, calculated as 100% by total mass, include:

[0050] 42-48 parts of triethyl phosphate, 15-23 parts of 2-methylthiobenzothiazole, 16-18 parts of triethylamine, 15-17 parts of alcohol compound, and 2-4 parts of emulsifier.

[0051] Optionally, the raw materials of the coal preparation foaming agent are calculated in parts, and the raw materials of the coal preparation foaming agent are calculated in parts, triethyl phosphate can be 42 parts, 43 parts, 45 parts, 47 parts or any value between 42 parts and 48 parts, 2-methylthiobenzothiazole can be 15 parts, 16 parts, 18 parts, 20 parts, 22 parts or any value between 15 parts and 23 parts, triethylamine can be 16 parts, 17 parts, 18 parts or any value between 16 parts and 18 parts, the alcohol compound can be 15 parts, 16 parts, 17 parts or any value between 15 parts and 17 parts, and the emulsifier can be 2 parts, 3 parts, 4 parts or any value between 2 parts and 4 parts.

[0052] It should be noted that reducing the proportion of raw materials to obtain the optimal dosage ratio can make the preparation of the agent more targeted and the synergistic effect between the various raw materials can be maximized, making the foam properties more stable and the subsequent three-phase foam easy to break without affecting the subsequent dehydration effect.

[0053] In some embodiments, the alcohol compound includes one or more of methanol, ethanol, and isopropanol.

[0054] In some embodiments, the emulsifier includes Span 80.

[0055] It should be noted that when the emulsifier is Span 80, the molecular structure of Span 80 is unique, with both hydrophobic fatty acid chains and hydrophilic polyoxyethylene chains. This structure enables it to form micelles between different phases, which can effectively disperse oil droplets in the water phase, or disperse water droplets in the oil phase. During the emulsification process, the tiny micelles formed by Span 80 between the two incompatible liquids increase the surface area of ​​contact between the two phases, thereby achieving a better emulsification effect.

[0056] The second aspect of the present application provides a method for preparing the coal preparation foaming agent, comprising:

[0057] The raw materials are mixed.

[0058] In some embodiments, the mixing comprises:

[0059] The triethyl phosphate and part of the alcohol compound are first mixed to obtain a solution A;

[0060] The 2-methylthiobenzothiazole and the remaining alcohol compound are mixed for a second time to obtain a solution B;

[0061] Mixing the solution A and the solution B for the third time to obtain a solution C;

[0062] The solution C, triethylamine and emulsifier are mixed for the fourth time.

[0063] It should be noted that the step-by-step preparation can make the flotation frother more fully dissolved and dispersed, and the intermediate products can also be used as raw materials for other reagents. The preparation of reagents is convenient and has a high safety factor.

[0064] The third aspect of the present application provides a coal flotation method, comprising:

[0065] The raw coal ore is slurried to obtain slurry;

[0066] The ore pulp, the coal preparation frother or the coal preparation frother prepared by the preparation method of the coal preparation frother, and a collector are mixed, and clean coal is obtained by flotation.

[0067] In some embodiments, the coal flotation method satisfies at least one of the following conditions:

[0068] A. The concentration of the ore pulp is 80g / L-100g / L of raw ore;

[0069] Optionally, the concentration of the slurry may be 80 g / L of raw ore, 90 g / L of raw ore, 100 g / L of raw ore, or any value between 80 g / L of raw ore and 100 g / L of raw ore;

[0070] B. The dosage of the collector is 3kg / t-4kg / t of raw ore;

[0071] Optionally, the amount of the collector can be 3kg / t of raw ore, 3.5kg / t of raw ore, 4kg / t of raw ore, or any value between 3kg / t of raw ore and 4kg / t of raw ore;

[0072] C. The collector includes diesel.

[0073] It should be noted that when the collector includes diesel, the role of the foaming agent is mainly to promote the combination of minerals and bubbles to achieve separation in water, while the role of diesel is mainly to provide hydrophobicity in the aqueous medium, form bubbles and adsorb on coal and minerals, thereby achieving separation. In the two-agent system, diesel and the foaming agent have a good synergistic effect, and the hydrophobic interaction energy between particles is mainly hydrophobic. Compared with the single-agent system, the "energy barrier" of the total potential energy between particles is greatly reduced. The lower the "energy barrier", the greater the attraction energy between particles, and the more conducive to the coagulation and floating of fine coal particles, which better explains the result that the optimal dosage of the agent should be selected for flotation.

[0074] In some embodiments, the amount of the coal preparation foaming agent used is 125g / t-150g / t-ore.

[0075] Optionally, the dosage of the coal preparation foaming agent can be 125g / t raw ore, 130g / t raw ore, 135g / t raw ore, 140g / t raw ore, 145g / t raw ore, 150g / t raw ore or any value between 125g / t raw ore and 150g / t raw ore.

[0076] The embodiments of the present application will be described in detail below in conjunction with specific examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If specific conditions are not specified in the examples, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0077] Example 1

[0078] In a first aspect, the present embodiment provides a coal preparation foaming agent, the raw materials of which include:

[0079] 45 parts of triethyl phosphate, 20 parts of 2-methylthiobenzothiazole, 17 parts of triethylamine, 9 parts of ethanol, 3 parts of methanol, 3 parts of isopropanol, and 3 parts of emulsifier Span 80.

[0080] A second aspect of this embodiment provides a method for preparing a coal preparation foaming agent, comprising:

[0081] Triethyl phosphate and ethanol were stirred in a stirred reactor for 30 min to obtain solution A;

[0082] Solution A, 2-methylthiobenzothiazole, methanol and isopropanol are mixed to obtain solution B;

[0083] Solution B, triethylamine and emulsifier were mixed to obtain a coal preparation foaming agent. The entire preparation process took 1 hour.

[0084] The infrared spectrum of the coal preparation foaming agent is as follows Figure 1 As shown, at 2955.18cm -1 、2923.78cm -1 and 2854.13cm -1 The absorption peak at 1737.86cm belongs to the CH stretching vibration mode, indicating that triethyl phosphate and triethylamine are present in the product; -1 The absorption peak at 1599.49cm belongs to the C=O stretching vibration mode, which is related to ester compounds; -1 and 1511.36cm -1 The absorption peak is located in the stretching vibration region of aromatic C=C and C=N (1400-1600cm -1 ), the specific wave number depends on the degree of conjugation and environment in benzothiazole. The existence of absorption peaks in this region indicates that there are a large number of benzothiazole derivative structures in the composition; due to the rich CH component of alkanes, 1456.6cm -1 The absorption peak at 1246.79cm is mainly related to the methylene bending vibration mode; -1 The position is mainly related to the P=O stretching vibration in phosphate ester; 1093cm -1 The absorption peaks near 655.19 cm-1 are relatively strong and overlap with each other. This region contains the stretching vibration modes of alcohol compounds CO and POC in phosphate esters. Since 2-methylthiobenzothiazole contains a sulfide (CS) bond, it has a peak at 655.19 cm-1. -1 The overlapping peaks nearby may be related to the presence of sulfur atoms. Through the above analysis, it can be determined that the absorption peak composition is consistent with the infrared characteristics of the complex of phosphate and benzothiazole derivatives.

[0085] The third aspect of the present embodiment provides a coal flotation method, which specifically comprises: using low-rank coal from Inner Mongolia as the coal ore, slurrying the ore to obtain a slurry with a concentration of 100 g / L of the ore, adding 3 kg / t of diesel to the slurry, stirring for 2 minutes, then adding a frother, stirring for 1 minute, aerating to form a stable foam layer, and scraping the foam for 3 minutes, and the product hung out is clean coal;

[0086] In this embodiment, two experiments were carried out according to the above steps. The dosage of the frother in the first experiment was 125 g / t of the raw ore, and the dosage of the frother in the second experiment was 150 g / t of the raw ore.

[0087] The pulp during flotation is Figure 2 shown.

[0088] Example 2

[0089] In a first aspect, the present embodiment provides a coal preparation foaming agent, the raw materials of which include:

[0090] 45 parts of triethyl phosphate, 20 parts of 2-methylthiobenzothiazole, 15 parts of triethylamine, 6 parts of ethanol, 5 parts of methanol, 5 parts of isopropanol, and 4 parts of emulsifier Span 80.

[0091] A second aspect of this embodiment provides a method for preparing a coal preparation foaming agent, comprising:

[0092] Triethyl phosphate and ethanol were mixed and stirred for 30 minutes to obtain solution A;

[0093] Mix 2-methylthiobenzothiazole, methanol and isopropanol to obtain solution B;

[0094] Mix solution A and solution B to obtain solution C;

[0095] Solution C, triethylamine and an emulsifier are mixed to obtain a coal preparation foaming agent. The entire preparation process takes 1 hour.

[0096] The third aspect of this embodiment provides a coal flotation method, which is consistent with the first embodiment.

[0097] Example 3

[0098] In a first aspect, the present embodiment provides a coal preparation foaming agent, the raw materials of which include:

[0099] 45 parts of triethyl phosphate, 20 parts of 2-methylthiobenzothiazole, 16 parts of triethylamine, 5 parts of ethanol, 6 parts of methanol, 6 parts of isopropanol, and 2 parts of emulsifier Span 80.

[0100] A second aspect of this embodiment provides a method for preparing a coal preparation foaming agent, comprising:

[0101] Triethyl phosphate and ethanol were stirred in a stirred reactor for 30 min to obtain solution A;

[0102] Solution A, 2-methylthiobenzothiazole, methanol and isopropanol are mixed to obtain solution B;

[0103] Solution B, triethylamine and emulsifier were mixed to obtain a coal preparation foaming agent. The entire preparation process took 1 hour.

[0104] The third aspect of this embodiment provides a coal flotation method, which is consistent with the first embodiment.

[0105] Example 4

[0106] In a first aspect, the present embodiment provides a coal preparation foaming agent, the raw materials of which include:

[0107] 45 parts of triethyl phosphate, 20 parts of 2-methylthiobenzothiazole, 16 parts of triethylamine, 4 parts of ethanol, 7 parts of methanol, 7 parts of isopropanol, and 1 part of emulsifier Span 80.

[0108] A second aspect of this embodiment provides a method for preparing a coal preparation foaming agent, comprising:

[0109] Triethyl phosphate and ethanol were stirred in a stirred reactor for 30 min to obtain solution A;

[0110] Solution A, 2-methylthiobenzothiazole, methanol and isopropanol are mixed to obtain solution B;

[0111] Solution B, triethylamine and emulsifier were mixed to obtain a coal preparation foaming agent. The entire preparation process took 1 hour.

[0112] The third aspect of this embodiment provides a coal flotation method, which is consistent with the first embodiment.

[0113] Comparative Example 1

[0114] The difference between this comparative example and Example 1 is that triethyl phosphate is not added in this comparative example.

[0115] Comparative Example 2

[0116] The difference between this comparative example and Example 1 is that 2-methylthiobenzothiazole is not added in this comparative example.

[0117] Comparative Example 3

[0118] The difference between this comparative example and Example 1 is that triethylamine is not added in this comparative example.

[0119] Comparative Example 4

[0120] The difference between this comparative example and Example 1 is that no emulsifier is added in this comparative example.

[0121] Comparative Example 5

[0122] The difference between this comparative example and Example 1 is that the raw materials used in this comparative example are calculated by parts, including:

[0123] 40 parts of triethyl phosphate, 25 parts of 2-methylthiobenzothiazole, 10 parts of triethylamine, 19 parts of alcohol compound, and 6 parts of emulsifier.

[0124] Comparative Example 6

[0125] The difference between this comparative example and Example 1 is that when the coal flotation method is tested twice in this comparative example, the dosage of the frother is 100 g / t of the original ore and 170 g / t of the original ore respectively.

[0126] Comparative Example 1

[0127] The difference between the coal flotation method of this comparative example and that of Example 1 is that the frother of this comparative example is 2-octanol.

[0128] The results of the coal flotation method tests of the above embodiments, comparative examples and control examples are shown in Table 1.

[0129] Table 1 Flotation test

[0130]

[0131] As shown in Table 1, the test results of Examples 1-4 of the present invention are compared with 2-octanol, and the yield has been significantly improved, and the clean coal ash content is almost the same, all within the qualified interval range (12-13). It is found through the test results of Comparative Examples 1-4 that the lack of a certain raw material will affect the clean coal yield or ash content. In order to ensure the yield and ash content, the raw materials disclosed by the present invention are indispensable. It is found through the test results of Comparative Example 5 that the dosage ratio of the reagent raw materials should be within the agreed range, otherwise it will affect the clean coal ash content, and it is easy to control the ash content. It is found through Comparative Example 6 that the dosage of the reagent is best within the range of 125-150g / t, and the yield and ash content can be well controlled within this range to achieve a good recovery index.

[0132] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0133] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the above claims, any one of the claimed embodiments may be used in any combination. The information disclosed in this background technology section is intended only to deepen the understanding of the overall background technology of the present application and should not be regarded as an admission or in any form of implication that the information constitutes prior art known to those skilled in the art.

Claims

1. A coal preparation foaming agent, characterized in that: The raw materials thereof, calculated in parts, include: 40-50 parts of triethyl phosphate, 12-25 parts of 2-methylthiobenzothiazole, 12-23 parts of triethylamine, 12-20 parts of alcohol compound, and 1-5 parts of emulsifier.

2. The coal preparation foaming agent according to claim 1, characterized in that: The raw materials thereof, calculated based on the total mass as 100%, include: 42-48 parts of triethyl phosphate, 15-23 parts of 2-methylthiobenzothiazole, 15-20 parts of triethylamine, 15-18 parts of alcohol compounds, and 1-4 parts of emulsifier.

3. The coal preparation foaming agent according to claim 2, characterized in that: The raw materials thereof, calculated based on the total mass as 100%, include: 42-48 parts of triethyl phosphate, 15-23 parts of 2-methylthiobenzothiazole, 16-18 parts of triethylamine, 15-17 parts of alcohol compound, and 2-4 parts of emulsifier.

4. The coal preparation foaming agent according to claim 1, characterized in that: The alcohol compound includes one or more of methanol, ethanol and isopropanol.

5. The coal preparation foaming agent according to any one of claims 1 to 4, characterized in that: The emulsifier includes Span 80.

6. A method for preparing a coal preparation foaming agent according to any one of claims 1 to 5, characterized in that: include: The raw materials are mixed.

7. The method for preparing a coal preparation foaming agent according to claim 6, characterized in that: The mixing includes: The triethyl phosphate and part of the alcohol compound are first mixed to obtain a solution A; The 2-methylthiobenzothiazole and the remaining alcohol compound are mixed for a second time to obtain a solution B; Mixing the solution A and the solution B for the third time to obtain a solution C; The solution C, triethylamine and emulsifier are mixed for the fourth time.

8. A method for coal flotation, characterized in that: include: The raw coal ore is slurried to obtain slurry; The ore pulp, the coal preparation frother according to any one of claims 1 to 5 or the coal preparation frother prepared by the preparation method of the coal preparation frother according to claim 6 or 7, and a collector are mixed and floated to obtain clean coal.

9. The coal flotation method according to claim 8, characterized in that: At least one of the following conditions is met: A. The concentration of the ore pulp is 80g / L-100g / L of raw ore; B. The dosage of the collector is 3kg / t-4kg / t of raw ore; C. The collector includes diesel.

10. The coal flotation method according to claim 8 or 9, characterized in that: The usage of the coal preparation foaming agent is 125 g / t-150 g / t of raw ore.

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