Coal slime flotation regulator and preparation method thereof

Abstract

The invention relates to a coal slime flotation regulator and a preparation method thereof, the coal slime flotation regulator comprises polysaccharide, a surfactant, a dispersant, an emulsifier and water, the surfactant comprises a benzene ring-containing nonionic surfactant, a straight-chain nonionic surfactant, an ester group-containing ampholytic surfactant and a cationic surfactant, and the dispersant comprises a dispersant, an emulsifier and water. The preparation method comprises the following steps: (1) mixing polysaccharide and water, and carrying out ultrasonic treatment; (2) mixing the mixed solution subjected to ultrasonic treatment in the step (1) with a surfactant, and reacting under the action of microwaves; and (3) mixing the solution after the reaction in the step (2) with a dispersing agent and an emulsifying agent to obtain the coal slime flotation regulator. A polysaccharide-surfactant block copolymer system is constructed through an ultrasonic-microwave synthesis reaction, and through the synergistic effect of the block copolymer system, the dispersing agent and the emulsifying agent, the formed regulator is good in stability, lasting in action time, high in selectivity and good in flotation effect.

Description

Technical Field

[0001] The invention relates to the technical field of coal slime flotation, and in particular to a coal slime flotation regulator and a preparation method thereof. Background Art

[0002] With the increase in the proportion of mechanized coal mining and the rapid development of heavy medium coal preparation, my country's coal slime has shown characteristics such as micronization, high ash content, and high content of intergrowth, which makes the separation of coal slime more difficult. When dealing with this type of coal slime, traditional separation methods often have problems such as weak recovery capacity and poor process adaptability, so they need to be improved through technical means.

[0003] Coal slime flotation is currently recognized as one of the most economical and effective separation technologies for fine coal slime ash reduction. However, the flotation process is affected by many factors, including coal slime properties, flotation equipment performance, flotation process, flotation reagents, and reagent system. In order to improve flotation efficiency and quality, these factors need to be optimized and controlled. Among them, flotation adjusters, as an important flotation aid, play a key role in adjusting the surface properties of coal slime and enhancing its adsorption capacity with bubbles.

[0004] The main function of the regulator is to affect the interaction between minerals and collectors, thereby improving the flotation effect. For some high-ash and fine-particle coal slimes, the use of regulators can often achieve better flotation effects. However, existing regulators mostly focus on strengthening a certain functional characteristic, lacking a strong stability regulator that can both reduce the ash content of clean coal and increase the clean coal yield, and is suitable for the flotation of coal slimes of different coal qualities. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a coal slime flotation regulator. The coal slime flotation regulator prepared by the preparation method has good stability, good flotation effect and wide application range.

[0006] Another object of the present invention is to provide a coal slime flotation conditioning agent prepared by the above preparation method.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is: On one hand, the present invention provides a method for preparing a coal slime flotation adjuster. The coal slime flotation adjuster comprises polysaccharide, surfactant, dispersant, emulsifier and water. The surfactant comprises a nonionic surfactant containing a benzene ring, a linear nonionic surfactant, an ester-containing amphoteric surfactant and a cationic surfactant. The weight content of the nonionic surfactant containing a benzene ring in the coal slime flotation adjuster is greater than the weight content of the linear nonionic surfactant in the coal slime flotation adjuster, greater than the weight content of the ester-containing amphoteric surfactant in the coal slime flotation adjuster, and greater than the weight content of the cationic surfactant in the coal slime flotation adjuster. The preparation method comprises the following steps: (1) mixing the polysaccharide and the water and subjecting the mixture to ultrasonic treatment; (2) mixing the mixed solution after ultrasonic treatment in step (1) with the surfactant and reacting them under the action of microwaves; (3) The solution obtained after the reaction in step (2) is mixed with the dispersant and the emulsifier to obtain the coal slime flotation adjuster.

[0008] The present invention activates the hydroxyl, amino, carboxyl and other groups on the polysaccharide through the action of ultrasound and microwaves, thereby undergoing a graft copolymerization reaction with a surfactant to form a polysaccharide-surfactant block copolymer system with a certain network structure, which has a better stability effect, can not only exert the inhibitory effect of the polysaccharide to reduce the ash content of the clean coal, but also exert the amphiphilic effect of the surfactant to improve the capture characteristics of the hydrophobic collector, thereby improving the clean coal yield. The present invention also further improves the flotation effect of the adjuster by optimizing the components of the surfactant. The present invention also significantly improves the stability, selectivity and flotation effect of the adjuster by adding a dispersant and an emulsifier to the adjuster system through their synergistic effect with the polysaccharide-surfactant block copolymer system.

[0009] Preferably, the polysaccharide is selected from one or more of oxidized starch, carboxymethyl cellulose, chitosan, and gum arabic. This type of polysaccharide is a polymer composed of many monosaccharides interconnected by glycosidic bonds, and its structure is a long straight chain or branched chain structure, and has high compatibility and biodegradability.

[0010] Preferably, the weight content of the polysaccharide in the coal slime flotation regulator is 5% to 12%, more preferably 7% to 10%, such as 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, and 10%.

[0011] Preferably, the nonionic surfactant containing a benzene ring is selected from one or more of alkylphenol polyoxyethylene ethers, and more preferably alkylphenol polyoxyethylene ethers having 8 to 12 carbon atoms, such as octylphenol polyoxyethylene ether.

[0012] Preferably, the weight content of the nonionic surfactant containing a benzene ring in the coal slime flotation adjuster is 1.4% to 1.9%, more preferably 1.6% to 1.8%, such as 1.6%, 1.65%, 1.7%, 1.75%, 1.8%.

[0013] Preferably, the linear nonionic surfactant is selected from one or more of alkyl alcohol polyoxyethylene ethers, and more preferably alkyl alcohol polyoxyethylene ethers having 10 to 14 carbon atoms, such as dodecyl alcohol polyoxyethylene ether.

[0014] Preferably, the weight content of the linear nonionic surfactant in the coal slime flotation adjuster is 1.1% to 1.5%, more preferably 1.2% to 1.4%, such as 1.2%, 1.25%, 1.3%, 1.35%, 1.4%.

[0015] Preferably, the amphoteric surfactant containing an ester group is dodecyldimethylaminoethyl lactone.

[0016] Preferably, the weight content of the ester-containing amphoteric surfactant in the coal slime flotation adjuster is 0.3% to 0.8%, more preferably 0.4% to 0.65%, such as 0.4%, 0.45%, 0.55%, 0.55%, 0.6%, 0.65%.

[0017] Preferably, the cationic surfactant is cetyltrimethylammonium bromide.

[0018] Preferably, the weight content of the cationic surfactant in the coal slime flotation adjusting agent is 0.01% to 0.2%, more preferably 0.1% to 0.2%, such as 0.1%, 0.12%, 0.14%, 0.16%, 0.18%, 0.2%.

[0019] Preferably, the temperature of the ultrasonic treatment is 30°C to 50°C, and the time is 20min to 40min.

[0020] More preferably, the temperature of the ultrasonic treatment is 35°C to 45°C, and the time is 25min to 35min.

[0021] Preferably, the reaction temperature is 50°C to 70°C, and the reaction time is 20min to 40min.

[0022] More preferably, the reaction temperature is 55°C to 65°C, and the reaction time is 25min to 35min.

[0023] Preferably, the microwave action is performed using a microwave hydrothermal parallel synthesizer, and the power of the microwave hydrothermal parallel synthesizer is 400W~600W, more preferably 450W~550W, such as 450W, 480W, 500W, 530W, 550W.

[0024] Preferably, the dispersant is selected from one or more inorganic sodium salts.

[0025] Further preferably, the dispersant is selected from one or more of sodium hexametaphosphate, sodium silicate, and sodium carbonate. Such sodium salts can increase the absolute value of the particle surface potential, produce a steric effect, increase the barrier between coal particles, and make the coal particles dispersed. It can also adjust the pH value of the system as a whole, and can also be randomly embedded in the block tool strips, with a longer action time.

[0026] Preferably, the weight content of the dispersant in the coal slime flotation adjusting agent is 0.5% to 2%, more preferably 1% to 1.5%, such as 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%.

[0027] In some embodiments, the dispersant is sodium hexametaphosphate, sodium silicate and sodium carbonate, the weight content of sodium hexametaphosphate in the coal slime flotation adjuster is 0.35%~1%, the weight content of sodium silicate in the coal slime flotation adjuster is 0.1%~0.3%, and the weight content of sodium carbonate in the coal slime flotation adjuster is 0.05%~0.2%.

[0028] Preferably, the emulsifier is selected from one or more of Tween and Span.

[0029] Preferably, the weight content of the emulsifier in the coal slime flotation adjuster is 1% to 3%, more preferably 1.5% to 2.5%, such as 1.5%, 1.8%, 2%, 2.3%, 2.5%.

[0030] In some embodiments, the emulsifier is Tween and Span, the weight content of Tween in the coal slime flotation adjuster is 0.8%~1.5%, and the weight content of Span in the coal slime flotation adjuster is 0.5%~1%.

[0031] Preferably, based on the total weight of the coal slime flotation regulator being 100%, it comprises the following components: Polysaccharide 5%~12%; Nonionic surfactants containing benzene rings 1.4%~1.9%; Linear nonionic surfactant 1.1%~1.5%; Amphoteric surfactants containing ester groups 0.3%~0.8%; Cationic surfactant 0.01%~0.2%; Dispersant 0.5%~2%; Emulsifier 1%~3%; Water balance.

[0032] In some embodiments, based on the total weight of the coal slime flotation regulator being 100%, it includes the following components: Polysaccharide 5%~12%; Nonionic surfactants containing benzene rings 1.4%~1.9%; Linear nonionic surfactant 1.1%~1.5%; Amphoteric surfactants containing ester groups 0.3%~0.8%; Cationic surfactant 0.01%~0.2%; Sodium hexametaphosphate 0.35%~1%; Sodium silicate 0.1%~0.3%; Sodium carbonate 0.05%~0.2%; Tween 0.8%~1.5%; Span 0.5%~1%; Water balance.

[0033] Further preferably, based on the total weight of the coal slime flotation regulator being 100%, it comprises the following components: Polysaccharide 7%~10%; Nonionic surfactants containing benzene rings 1.6%~1.8%; Linear nonionic surfactant 1.2%~1.4%; Amphoteric surfactants containing ester groups 0.4%~0.65%; Cationic surfactant 0.1%~0.2%; Sodium hexametaphosphate 0.5%~0.9%; Sodium silicate 0.15%~0.3%; Sodium carbonate 0.1%~0.15%; Tween 1%~1.3%; Span 0.6%~0.8%; Water balance.

[0034] Preferably, the step (3) comprises stirring and mixing the solution after the reaction in the step (2) with the dispersant at 30°C to 50°C, and then adding the emulsifier and stirring and mixing them at 40°C to 50°C.

[0035] Further preferably, the step (3) comprises stirring and mixing the solution after the reaction in the step (2) with the dispersant at 35°C-45°C, and then adding the emulsifier and stirring and mixing them at 43°C-48°C.

[0036] In some embodiments, the stirring speed is independently 100 r / min to 150 r / min, such as 100 r / min, 100 r / min, 120 r / min, 130 r / min, and 150 r / min.

[0037] In some embodiments, the stirring and mixing time is independently 20 min to 40 min, such as 20 min, 25 min, 30 min, 35 min, and 40 min.

[0038] Another aspect of the present invention provides a coal slime flotation regulator prepared by the preparation method as described above.

[0039] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: The present invention constructs a polysaccharide-surfactant block copolymer system through an ultrasonic-microwave synthesis reaction. Through the synergistic effect of the block copolymer system, a dispersant and an emulsifier, the formed regulator has good stability, a lasting action time, strong selectivity, a good flotation effect and a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 The following are photos of some embodiments and some comparative examples of the present invention. DETAILED DESCRIPTION

[0041] The present invention is further described below in conjunction with the examples. However, the present invention is not limited to the following examples. The implementation conditions used in the examples can be further adjusted according to the different requirements of specific use, and the implementation conditions not specified are conventional conditions in the industry. The technical features involved in each embodiment of the present invention can be combined with each other as long as they do not conflict with each other.

[0042] Unless otherwise specified, the raw materials and instruments mentioned below are all commercially available products or can be prepared by referring to the existing technology. Among them, oxidized starch was purchased from Shandong Zhucheng Xingmao Corn Development Co., Ltd., CAS No.: 65996-62-5; octylphenol polyoxyethylene ether was purchased from Sinopharm Chemical Reagent Co., Ltd., CAS No.: 9036-19-5; dodecyl alcohol polyoxyethylene ether was purchased from Sinopharm Chemical Reagent Co., Ltd., CAS No.: 9002-92-0. Example 1

[0043] The present embodiment provides a coal slime flotation adjusting agent, which comprises, based on the total weight of the coal slime flotation adjusting agent as 100%, 84.6wt% of water, 8.7wt% of oxidized starch, 1.7wt% of octylphenol polyoxyethylene ether, 1.3wt% of dodecyl alcohol polyoxyethylene ether, 0.55wt% of dodecyl dimethylamine ethyl lactone, 0.15wt% of hexadecyl trimethyl ammonium bromide, 0.77wt% of sodium hexametaphosphate, 0.22wt% of sodium silicate, 0.11wt% of sodium carbonate, 1.14wt% of Tween 80, and 0.76wt% of Span 60.

[0044] The preparation method of the coal slime flotation adjusting agent comprises the following steps: (1) Dissolve the oxidized starch in water and place it in an ultrasonic cell disruptor for 30 min at 40°C; (2) adding octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, dodecyl dimethylaminoethyl lactone, and hexadecyl trimethyl ammonium bromide to the solution in step (1), and placing the mixture in a microwave hydrothermal parallel synthesizer for reaction at a microwave power of 500 W, a temperature of 60° C., and a reaction time of 30 min; (3) Add sodium hexametaphosphate, sodium silicate and sodium carbonate to the solution in step (2), and stir on a magnetic stirrer at a speed of 120 r / min, a temperature of 40°C, and a time of 30 min; (4) Add Tween 80 and Span 60 to the solution in step (3), place the solution on a magnetic stirrer and stir at a speed of 120 r / min, a temperature of 45°C, and a time of 30 min to obtain a coal slime flotation adjuster. Example 2

[0045] This embodiment provides a coal slime flotation regulator, and the preparation method is the same as that of Embodiment 1, except that the oxidized starch in the coal slime flotation regulator is replaced with an equal weight of carboxymethyl cellulose. Example 3

[0046] This embodiment provides a coal slime flotation regulator, and the preparation method is the same as that of Embodiment 1, except that the oxidized starch in the coal slime flotation regulator is replaced with an equal weight of chitin. Example 4

[0047] This embodiment provides a coal slime flotation regulator, and the preparation method is the same as that of Embodiment 1, except that the oxidized starch in the coal slime flotation regulator is replaced with an equal weight of gum arabic.

[0048] Comparative Example 1 The present comparative example provides a coal slime flotation adjusting agent, which comprises, based on the total weight of the coal slime flotation adjusting agent as 100%, 93.3wt% of water, 1.7wt% of octylphenol polyoxyethylene ether, 1.3wt% of dodecyl alcohol polyoxyethylene ether, 0.55wt% of dodecyl dimethylaminoethyl lactone, 0.15wt% of hexadecyl trimethyl ammonium bromide, 0.77wt% of sodium hexametaphosphate, 0.22wt% of sodium silicate, 0.11wt% of sodium carbonate, 1.14wt% of Tween 80, and 0.76wt% of Span 60.

[0049] The preparation method of the coal slime flotation adjusting agent comprises the following steps: (1) Preheat water to 40°C in a water bath; (2) adding octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, dodecyl dimethylaminoethyl lactone, and hexadecyl trimethyl ammonium bromide to the water in step (1), and placing the mixture in a microwave hydrothermal parallel synthesizer for reaction at a microwave power of 500 W, a temperature of 60° C., and a reaction time of 30 min; (3) Add sodium hexametaphosphate, sodium silicate and sodium carbonate to the solution in step (2), and stir on a magnetic stirrer at a speed of 120 r / min, a temperature of 40°C, and a time of 30 min; (4) Add Tween 80 and Span 60 to the solution in step (3), place the mixture on a magnetic stirrer and stir at a speed of 120 r / min, a temperature of 45° C., and a time of 30 min to obtain a coal slime flotation adjuster free of polysaccharides.

[0050] Comparative Example 2 This comparative example provides a coal slime flotation regulator, which comprises: 91.3 wt % of water and 8.7 wt % of oxidized starch, based on the total weight of the coal slime flotation regulator being 100 wt %.

[0051] The preparation method of the coal slime flotation regulator comprises placing oxidized starch in an ultrasonic cell disruptor for ultrasonic treatment for 30 minutes at a temperature of 40° C., and obtaining a coal slime flotation inhibitor containing only oxidized starch after the treatment.

[0052] Comparative Example 3 This comparative example provides a coal slime flotation regulator, and the preparation method is the same as that of comparative example 2, except that the oxidized starch is replaced with an equal weight of carboxymethyl cellulose.

[0053] Comparative Example 4 This comparative example provides a coal slime flotation regulator, and the preparation method is the same as that of comparative example 2, except that the oxidized starch is replaced with an equal weight of chitin.

[0054] Comparative Example 5 This comparative example provides a coal slime flotation regulator, and the preparation method is the same as that of comparative example 2, except that the oxidized starch is replaced with an equal weight of gum arabic.

[0055] Comparative Example 6 This comparative example provides a coal slime flotation regulator, which comprises: 88.3wt% of water, 8.7wt% of oxidized starch, 0.77wt% of sodium hexametaphosphate, 0.22wt% of sodium silicate, 0.11wt% of sodium carbonate, 1.14wt% of Tween 80, and 0.76wt% of Span 60, based on the total weight of the coal slime flotation regulator as 100%.

[0056] The preparation method of the coal slime flotation adjusting agent comprises the following steps: (1) Dissolve the oxidized starch in water and place it in an ultrasonic cell disruptor for 30 min at 40°C; (2) Add sodium hexametaphosphate, sodium silicate and sodium carbonate to the solution in step (1), and stir on a magnetic stirrer at a speed of 120 r / min, a temperature of 40°C, and a time of 30 min; (3) Add Tween 80 and Span 60 to the solution in step (2), place the mixture on a magnetic stirrer and stir at a speed of 120 r / min, a temperature of 45°C, and a time of 30 min to obtain a coal slime flotation adjuster free of surfactant.

[0057] Comparative Example 7 The comparative example provides a coal slime flotation adjusting agent, which comprises, based on the total weight of the coal slime flotation adjusting agent as 100%, 85.7wt% of water, 8.7wt% of oxidized starch, 1.7wt% of octylphenol polyoxyethylene ether, 1.3wt% of dodecyl alcohol polyoxyethylene ether, 0.55wt% of dodecyl dimethylamine ethyl lactone, 0.15wt% of hexadecyl trimethyl ammonium bromide, 1.14wt% of Tween 80, and 0.76wt% of Span 60.

[0058] The preparation method of the coal slime flotation adjusting agent comprises the following steps: (1) Dissolve the oxidized starch in water and place it in an ultrasonic cell disruptor for 30 min at 40°C; (2) adding octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, dodecyl dimethylaminoethyl lactone, and hexadecyl trimethyl ammonium bromide to the solution in step (1), and placing the mixture in a microwave hydrothermal parallel synthesizer for reaction at a microwave power of 500 W, a temperature of 60° C., and a reaction time of 30 min; (3) Add Tween 80 and Span 60 to the solution in step (2), place the mixture on a magnetic stirrer and stir at a speed of 120 r / min, a temperature of 45°C, and a time of 30 min to obtain a coal slime flotation adjuster without a dispersant.

[0059] Comparative Example 8 The present comparative example provides a coal slime flotation adjusting agent, which comprises, based on the total weight of the coal slime flotation adjusting agent as 100%, 86.5wt% of water, 8.7wt% of oxidized starch, 1.7wt% of octylphenol polyoxyethylene ether, 1.3wt% of dodecyl alcohol polyoxyethylene ether, 0.55wt% of dodecyl dimethylaminoethyl lactone, 0.15wt% of hexadecyl trimethyl ammonium bromide, 0.77wt% of sodium hexametaphosphate, 0.22wt% of sodium silicate, and 0.11wt% of sodium carbonate.

[0060] The preparation method of the coal slime flotation adjusting agent comprises the following steps: (1) Dissolve the oxidized starch in water and place it in an ultrasonic cell disruptor for 30 min at 40°C; (2) adding octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, dodecyl dimethylaminoethyl lactone, and hexadecyl trimethyl ammonium bromide to the solution in step (1), and placing the mixture in a microwave hydrothermal parallel synthesizer for reaction at a microwave power of 500 W, a temperature of 60° C., and a reaction time of 30 min; (3) Sodium hexametaphosphate, sodium silicate and sodium carbonate were added to the solution in step (2), and the mixture was stirred on a magnetic stirrer at a speed of 120 r / min, a temperature of 40° C., and a time of 30 min to obtain a coal slime flotation adjuster without an emulsifier.

[0061] Comparative Example 9 This comparative example provides a coal slime flotation regulator, which is basically the same as Example 1, except that the preparation method is different.

[0062] The preparation method of the coal slime flotation regulator in this comparative example is: mixing the components according to a specified weight ratio, and stirring them sufficiently to obtain the coal slime flotation regulator without a reaction process.

[0063] Comparative Example 10 The comparative example provides a coal slime flotation adjusting agent, which comprises, based on the total weight of the coal slime flotation adjusting agent as 100%, 84.6wt% of water, 8.7wt% of oxidized starch, 1.7wt% of octylphenol polyoxyethylene ether, 1.3wt% of dodecyl alcohol polyoxyethylene ether, 0.7wt% of dodecyl dimethylaminoethyl lactone, 0.77wt% of sodium hexametaphosphate, 0.22wt% of sodium silicate, 0.11wt% of sodium carbonate, 1.14wt% of Tween 80 and 0.76wt% of Span 60.

[0064] The preparation method of the coal slime flotation adjusting agent comprises the following steps: (1) Dissolve the oxidized starch in water and place it in an ultrasonic cell disruptor for 30 min at 40°C; (2) adding octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether and dodecyl dimethylaminoethyl lactone to the solution in step (1), and placing the mixture in a microwave hydrothermal parallel synthesizer for reaction at a microwave power of 500 W, a temperature of 60° C. and a reaction time of 30 min; (3) Add sodium hexametaphosphate, sodium silicate and sodium carbonate to the solution in step (2), and stir on a magnetic stirrer at a speed of 120 r / min, a temperature of 40°C, and a time of 30 min; (4) Add Tween 80 and Span 60 to the solution in step (3), place the solution on a magnetic stirrer and stir at a speed of 120 r / min, a temperature of 45°C, and a time of 30 min to obtain a coal slime flotation adjuster.

[0065] Comparative Example 11 The comparative example provides a coal slime flotation adjusting agent, which comprises, based on the total weight of the coal slime flotation adjusting agent as 100%, 84.6wt% of water, 8.7wt% of oxidized starch, 1.7wt% of octylphenol polyoxyethylene ether, 1.3wt% of dodecyl alcohol polyoxyethylene ether, 0.7wt% of hexadecyltrimethylammonium bromide, 0.77wt% of sodium hexametaphosphate, 0.22wt% of sodium silicate, 0.11wt% of sodium carbonate, 1.14wt% of Tween 80, and 0.76wt% of Span 60.

[0066] The preparation method of the coal slime flotation adjusting agent comprises the following steps: (1) Dissolve the oxidized starch in water and place it in an ultrasonic cell disruptor for 30 min at 40°C; (2) adding octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether and hexadecyltrimethylammonium bromide to the solution in step (1), and placing the mixture in a microwave hydrothermal parallel synthesizer for reaction at a microwave power of 500 W, a temperature of 60° C. and a reaction time of 30 min; (3) Add sodium hexametaphosphate, sodium silicate and sodium carbonate to the solution in step (2), and stir on a magnetic stirrer at a speed of 120 r / min, a temperature of 40°C, and a time of 30 min; (4) Add Tween 80 and Span 60 to the solution in step (3), place the solution on a magnetic stirrer and stir at a speed of 120 r / min, a temperature of 45°C, and a time of 30 min to obtain a coal slime flotation adjuster.

[0067] Comparative Example 12 The comparative example provides a coal slime flotation adjusting agent, which comprises, based on the total weight of the coal slime flotation adjusting agent as 100%, 84.6wt% of water, 8.7wt% of oxidized starch, 3wt% of octylphenol polyoxyethylene ether, 0.55wt% of dodecyldimethylamine ethyl lactone, 0.15wt% of hexadecyltrimethylammonium bromide, 0.77wt% of sodium hexametaphosphate, 0.22wt% of sodium silicate, 0.11wt% of sodium carbonate, 1.14wt% of Tween 80 and 0.76wt% of Span 60.

[0068] The preparation method of the coal slime flotation adjusting agent comprises the following steps: (1) Dissolve the oxidized starch in water and place it in an ultrasonic cell disruptor for 30 min at 40°C; (2) adding octylphenol polyoxyethylene ether, dodecyl dimethylaminoethyl lactone, and hexadecyl trimethyl ammonium bromide to the solution in step (1), and placing the mixture in a microwave hydrothermal parallel synthesizer for reaction at a microwave power of 500 W, a temperature of 60° C., and a reaction time of 30 min; (3) Add sodium hexametaphosphate, sodium silicate and sodium carbonate to the solution in step (2), and stir on a magnetic stirrer at a speed of 120 r / min, a temperature of 40°C, and a time of 30 min; (4) Add Tween 80 and Span 60 to the solution in step (3), place the solution on a magnetic stirrer and stir at a speed of 120 r / min, a temperature of 45°C, and a time of 30 min to obtain a coal slime flotation adjuster.

[0069] Comparative Example 13 The comparative example provides a coal slime flotation adjusting agent, which comprises, based on the total weight of the coal slime flotation adjusting agent as 100%, 84.6wt% of water, 8.7wt% of oxidized starch, 0.925wt% of octylphenol polyoxyethylene ether, 0.925wt% of dodecyl alcohol polyoxyethylene ether, 0.925wt% of dodecyl dimethylamine ethyl lactone, 0.925wt% of hexadecyl trimethyl ammonium bromide, 0.77wt% of sodium hexametaphosphate, 0.22wt% of sodium silicate, 0.11wt% of sodium carbonate, 1.14wt% of Tween 80, and 0.76wt% of Span 60.

[0070] The preparation method of the coal slime flotation adjusting agent comprises the following steps: (1) Dissolve the oxidized starch in water and place it in an ultrasonic cell disruptor for 30 min at 40°C; (2) adding octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, dodecyl dimethylaminoethyl lactone, and hexadecyl trimethyl ammonium bromide to the solution in step (1), and placing the mixture in a microwave hydrothermal parallel synthesizer for reaction at a microwave power of 500 W, a temperature of 60° C., and a reaction time of 30 min; (3) Add sodium hexametaphosphate, sodium silicate and sodium carbonate to the solution in step (2), and stir on a magnetic stirrer at a speed of 120 r / min, a temperature of 40°C, and a time of 30 min; (4) Add Tween 80 and Span 60 to the solution in step (3), place the solution on a magnetic stirrer and stir at a speed of 120 r / min, a temperature of 45°C, and a time of 30 min to obtain a coal slime flotation adjuster.

[0071] The effect of coal slime flotation regulator was tested by flotation unit experiment: The flotation effect evaluation of the flotation unit experiment is mainly based on the following indicators: clean coal yield, clean coal ash content, tail coal ash content, and flotation improvement index. Among them, the clean coal yield is the ratio of the mass of clean coal scraped out after flotation to the total feed mass of floating coal powder before flotation, expressed as a percentage. The larger the clean coal yield value, the better; the clean coal ash content and tail coal ash content are determined in accordance with the "Industrial Analysis Method of Coal" (GB / T 212-2008), and the smaller the clean coal ash content value, the better; the flotation improvement index is determined in accordance with the "Method for Evaluation of Flotation Process Effect of Coal Preparation Plant" (GB / T 34164-2017), and the larger the flotation improvement index value, the better.

[0072] The flotation unit test was conducted on the above-mentioned coal slime flotation regulator. The flotation test method was carried out in accordance with the "Coal Powder (Mud) Laboratory Unit Flotation Test Method" (GB / T 4757-2013) for performance testing. The coal slime flotation regulator (i.e., regulator) was added after stirring and slurrying for 2 minutes, and then the collector and frother were added. The collector was 0# diesel and the frother was 2-octanol. The control group was the one without regulator. The flotation machine used a 1.5L XFD single-slot flotation machine, and the impeller speed of the flotation machine was set to 1800 r / min, and the unit air volume was 0.25 m 3 / (m 2 •min). The slurry concentration is 80g / L, the dosage of the adjusting agent is 500g / t dry coal slime, the dosage of the collecting agent is 800g / t dry coal slime, and the dosage of the frother is 100g / t dry coal slime.

[0073] Coking coal experiment: Different types of coal were selected for the experiment. First, 1 / 3 coking coal slime was selected. The sample was taken from Huaibei Mining Linhuan Coal Preparation Plant. The ash content of the flotation feed was 29.29%. After drying, crushing, screening, blending and shrinking, the coal slime was prepared into an analytical coal sample with a particle size of less than 0.5 mm according to the "Preparation Method of Coal Samples" (GB / T474-2008). The flotation test results are shown in Table 1.

[0074] Table 1

[0075] As can be seen from Table 1, the clean coal yield of the control group without the adjustment agent is 64.35%, the clean coal ash content is 11.33%, the tail coal ash content is 60.22%, and the flotation improvement index is 54.74%. By adding the adjustment agent prepared in the embodiment of the present invention, the clean coal yield can be increased by 2.99 to 4.54 percentage points, the clean coal ash content can be reduced by 0.78 to 0.95 percentage points, the tail coal ash content can be increased by 4.75 to 5.89 percentage points, and the flotation improvement index can be increased by 4.28 to 4.86 percentage points, indicating that the addition of the adjustment agent significantly improves the flotation effect.

[0076] By comparing Examples 1 to 4 of the present invention and Comparative Example 1, it is found that when no polysaccharide is added to the adjuster, the improvement of the adjuster on the flotation effect is limited. Except that the clean coal yield is slightly improved compared with the control group, the other indicators are equivalent to the control group, and the overall flotation effect is not as good as the present invention.

[0077] By comparing Examples 1 to 4 of the present invention and Comparative Examples 2 to 5, it is found that when the adjusting agent contains only polysaccharides but does not contain surfactants, emulsifiers, and dispersants, the clean coal ash content of Comparative Examples 2 to 5 is significantly reduced compared with the control group, but the clean coal yield and flotation improvement index are also greatly reduced, indicating that the adjusting agent containing only polysaccharides has a significant inhibitory effect, but at the same time it will also over-inhibit and reduce the economic benefits.

[0078] By comparing Example 1 of the present invention and Comparative Example 6, it is found that when the adjusting agent does not contain a surfactant, although the clean coal ash content is lower than that of the control group, the clean coal yield and flotation perfection index are not high, which are not as good as the examples of the present invention.

[0079] By comparing Example 1 of the present invention and Comparative Example 7, it is found that when the adjusting agent does not contain a dispersant, the ash content of the clean coal and the ash content of the tail coal do not change significantly compared with the control group, and the overall flotation improvement index is not as good as that of the example of the present invention.

[0080] By comparing Example 1 of the present invention and Comparative Example 8, it is found that when the adjuster does not contain an emulsifier, although the clean coal yield is increased and the clean coal ash content is reduced, the flotation perfection index is not as good as that of the example of the present invention.

[0081] By comparing Example 1 of the present invention with Comparative Example 9, it is found that the adjusting agent that directly mixes the raw materials together without ultrasonic and microwave reactions is inferior to the present application example in terms of clean coal yield, clean coal ash content, and flotation improvement index. The present invention constructs a "polysaccharide-surfactant" block copolymer system through ultrasonic-microwave synthesis reaction, and carries a dispersant, etc., to form an adjusting agent with better flotation effect, more stability and long-lasting action time.

[0082] By comparing the embodiments of the present invention with comparative examples 10 to 13, the present invention improves the flotation effect of the adjusting agent by using a compound of a cationic surfactant, an ester-containing amphoteric surfactant, a benzene-ring-containing nonionic surfactant and a straight-chain nonionic surfactant, and by adjusting the dosage of various surfactants.

[0083] High ash fat coal experiment: High-ash fat coal slime was selected and sampled from Huaibei Mining Linhuan Coal Preparation Plant. The ash content of flotation feed was 30.52%. After drying, crushing, screening, blending and shrinking, the coal slime was prepared into analytical coal samples with a particle size of less than 0.5 mm in accordance with the "Preparation Method of Coal Samples" (GB / T 474-2008). The flotation test results are shown in Table 2.

[0084] Table 2

[0085] As can be seen from Table 2, for high-ash fat coal, the synergistic effect of the regulator is more obvious. The clean coal yield of the control group without the regulator was 48.67%, the clean coal ash content was 12.3%, the tail coal ash content was 51.33%, and the flotation improvement index was 46.07%. By adding the regulators of Examples 1 to 4 of the present invention, the overall clean coal yield increased by about 10 percentage points, the clean coal ash content decreased by about 1 percentage point, the tail coal ash content increased by about 12 percentage points, and the flotation improvement index increased by about 14 percentage points, indicating that the addition of the regulator significantly improved the flotation effect. Similarly, the flotation effects of the regulators of Comparative Examples 1 to 13 were not as good as those of the embodiments of the present invention.

[0086] Stability test: Examples 1 to 4 and Comparative Examples 8 and 9 were subjected to a room temperature storage stability test. After each sample was prepared, it was placed at room temperature (25±5°C) for 1 week to observe its stability. The results are as follows: Figure 1 As shown. Figure 1 It can be seen that Examples 1 to 4 are uniform as a whole, without stratification or precipitation; Comparative Example 8 has a small amount of clear liquid precipitated on the upper layer, and Comparative Example 9 has obvious precipitation, and the stability is not as good as that of Examples 1 to 4.

[0087] The above detailed description of the present invention is intended to enable persons familiar with the art to understand the contents of the present invention and implement them. It does not limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a coal slime flotation conditioning agent, characterized in that: The coal slime flotation adjusting agent comprises polysaccharide, surfactant, dispersant, emulsifier and water, wherein the surfactant comprises a nonionic surfactant containing benzene ring, a linear nonionic surfactant, an ester-containing amphoteric surfactant and a cationic surfactant, wherein the weight content of the nonionic surfactant containing benzene ring in the coal slime flotation adjusting agent is greater than the weight content of the linear nonionic surfactant in the coal slime flotation adjusting agent, the weight content of the amphoteric surfactant containing ester group in the coal slime flotation adjusting agent is greater than the weight content of the cationic surfactant in the coal slime flotation adjusting agent, the nonionic surfactant containing benzene ring is selected from one or more of alkylphenol polyoxyethylene ethers, the linear nonionic surfactant is selected from one or more of alkyl alcohol polyoxyethylene ethers, the ester-containing amphoteric surfactant is dodecyldimethylaminoethyl lactone, and the cationic surfactant is hexadecyltrimethylammonium bromide. The preparation method comprises the following steps: (1) mixing the polysaccharide and the water and subjecting the mixture to ultrasonic treatment; (2) mixing the mixed solution after ultrasonic treatment in step (1) with the surfactant and reacting them under the action of microwaves; (3) The solution obtained after the reaction in step (2) is mixed with the dispersant and the emulsifier to obtain the coal slime flotation adjuster.

2. The method for preparing a coal slime flotation conditioning agent according to claim 1, characterized in that: The polysaccharide is selected from one or more of oxidized starch, carboxymethyl cellulose, chitosan, and gum arabic; and / or, The weight content of the polysaccharide in the coal slime flotation regulator is 5% to 12%.

3. The method for preparing the coal slime flotation adjusting agent according to claim 1, characterized in that: The weight content of the nonionic surfactant containing benzene ring in the coal slime flotation regulator is 1.4% to 1.9%; and / or, The weight content of the linear nonionic surfactant in the coal slime flotation regulator is 1.1% to 1.5%; and / or, The weight content of the amphoteric surfactant containing an ester group in the coal slime flotation regulator is 0.3% to 0.8%; and / or, The weight content of the cationic surfactant in the coal slime flotation regulator is 0.01% to 0.2%.

4. The method for preparing a coal slime flotation conditioning agent according to claim 1, characterized in that: The temperature of the ultrasonic treatment is 30°C to 50°C, and the time is 20min to 40min.

5. The method for preparing a coal slime flotation conditioning agent according to claim 1, characterized in that: The reaction temperature is 50°C to 70°C and the reaction time is 20min to 40min; and / or, The microwave action is performed using a microwave hydrothermal parallel synthesizer, and the power of the microwave hydrothermal parallel synthesizer is 400W~600W.

6. The method for preparing a coal slime flotation conditioning agent according to claim 1, characterized in that: The dispersant is selected from one or more of sodium hexametaphosphate, sodium silicate and sodium carbonate; and / or, The weight content of the dispersant in the coal slime flotation adjuster is 0.5% to 2%.

7. The method for preparing a coal slime flotation conditioning agent according to claim 6, characterized in that: The dispersant is sodium hexametaphosphate, sodium silicate and sodium carbonate. The weight content of sodium hexametaphosphate in the coal slime flotation adjuster is 0.35%~1%, the weight content of sodium silicate in the coal slime flotation adjuster is 0.1%~0.3%, and the weight content of sodium carbonate in the coal slime flotation adjuster is 0.05%~0.2%.

8. The method for preparing a coal slime flotation conditioning agent according to claim 1, characterized in that: The emulsifier is selected from one or more of Tween and Span; and / or, The weight content of the emulsifier in the coal slime flotation adjuster is 1% to 3%.

9. The method for preparing a coal slime flotation conditioning agent according to claim 1, characterized in that: Taking the total weight of the coal slime flotation regulator as 100%, it includes the following components: Polysaccharide 5%~12%; Nonionic surfactants containing benzene rings 1.4%~1.9%; Linear nonionic surfactant 1.1%~1.5%; Amphoteric surfactants containing ester groups 0.3%~0.8%; Cationic surfactant 0.01%~0.2%; Dispersant 0.5%~2%; Emulsifier 1%~3%; Water balance.

10. The method for preparing a coal slime flotation regulator according to claim 1, characterized in that: The step (3) comprises stirring and mixing the solution after the reaction in the step (2) and the dispersant at 30° C. to 50° C., and then adding the emulsifier and stirring and mixing them at 40° C. to 50° C.

11. A coal slime flotation conditioning agent, characterized in that: The coal slime flotation regulator is prepared by the preparation method according to any one of claims 1 to 10.

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