A coal slime flotation regulator and its preparation method

Abstract

The present invention relates to a slime flotation regulator and a preparation method thereof. The slime flotation regulator comprises a polysaccharide, a surfactant, a dispersant, an emulsifier and water. The surfactant comprises a nonionic surfactant containing a benzene ring, a straight-chain nonionic surfactant, an amphoteric surfactant containing an ester group and a cationic surfactant. The preparation method comprises the following steps: (1) mixing the polysaccharide and water and performing ultrasonic treatment; (2) mixing the mixture after ultrasonic treatment in step (1) with the surfactant and reacting under the action of microwave; (3) mixing the solution after the reaction in step (2) with the dispersant and the emulsifier to obtain the slime flotation regulator. The present invention constructs a polysaccharide-surfactant block copolymer system through an ultrasonic-microwave synthesis reaction. Through the synergistic action of the block copolymer system with the dispersant and the emulsifier, the formed regulator has good stability, a long action time, strong selectivity and excellent flotation effect.

Description

Technical Field

[0001] The present invention relates to the technical field of coal slime flotation, and particularly relates 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, coal slime in China shows characteristics such as fineness, high ash content, and large content of intergrowth bodies, which further increases the difficulty of coal slime separation. When dealing with this type of coal slime, traditional separation methods often have problems such as weak recovery ability and poor process adaptability, so improvement is needed through technical means.

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

[0004] The regulator mainly affects the interaction between minerals and collectors, thereby improving the flotation effect. For some coal slimes with high ash content and many fine particles, the use of regulators often can obtain better flotation effects. However, existing regulators mostly focus on strengthening a certain functional characteristic, lacking a regulator with strong stability, which can not only reduce the ash content of clean coal but also improve the recovery rate of clean coal and is applicable to the flotation of coal slimes with different coal qualities. Summary of the Invention

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

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

[0007] To achieve the above purpose, the technical solution adopted by the present invention is:

[0008] On the one hand, the present invention provides a preparation method of a slime flotation regulator. The slime flotation regulator includes polysaccharide, surfactant, dispersant, emulsifier and water. The surfactant includes a non-ionic surfactant containing a benzene ring, a straight-chain non-ionic surfactant, an amphoteric surfactant containing an ester group and a cationic surfactant. The weight content of the non-ionic surfactant containing a benzene ring in the slime flotation regulator > the weight content of the straight-chain non-ionic surfactant in the slime flotation regulator > the weight content of the amphoteric surfactant containing an ester group in the slime flotation regulator > the weight content of the cationic surfactant in the slime flotation regulator.

[0009] The preparation method includes the following steps:

[0010] (1) Mix the polysaccharide and the water and perform ultrasonic treatment.

[0011] (2) Mix the mixture after ultrasonic treatment in step (1) with the surfactant and react under the action of microwave.

[0012] (3) Mix the solution after the reaction in step (2) with the dispersant and the emulsifier to obtain the slime flotation regulator.

[0013] Through the action of ultrasonic and microwave, the present invention can activate groups such as hydroxyl, amino, and carboxyl groups on the polysaccharide, so as to carry out graft copolymerization reaction with the surfactant, forming a block copolymer system of polysaccharide-surfactant with a certain network structure. While having better stability, it can not only exert the inhibitory effect of the polysaccharide to reduce the ash content of clean coal, but also exert the amphiphilic effect of the surfactant to improve the capture characteristics of the hydrophobic collector, thereby increasing the clean coal recovery rate. The present invention also optimizes the components of the surfactant, further improving the flotation effect of the regulator. The present invention also adds a dispersant and an emulsifier to the regulator system, and through their common synergistic effect with the block copolymer system of polysaccharide-surfactant, significantly improves the stability, selectivity and flotation effect of the regulator.

[0014] Preferably, the polysaccharide is selected from one or more of oxidized starch, carboxymethyl cellulose, chitosan, and arabic gum. Such polysaccharides are polymers composed of many monosaccharides connected to each other through glycosidic bonds, with a long straight-chain or branched-chain structure, and having high compatibility and biodegradability.

[0015] Preferably, the weight content of the polysaccharide in the slime flotation regulator is 5% - 12%, and more preferably 7% - 10%, such as 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%.

[0016] Preferably, the non-ionic surfactant containing a benzene ring is selected from one or more of alkylphenol polyoxyethylene ethers, and further preferably alkylphenol polyoxyethylene ethers with 8 to 12 carbon atoms, such as octylphenol polyoxyethylene ether.

[0017] Preferably, the weight content of the non-ionic surfactant containing a benzene ring in the slime flotation regulator is 1.4% - 1.9%, further preferably 1.6% - 1.8%, such as 1.6%, 1.65%, 1.7%, 1.75%, 1.8%.

[0018] Preferably, the straight-chain non-ionic surfactant is selected from one or more of alkyl alcohol polyoxyethylene ethers, and further preferably alkyl alcohol polyoxyethylene ethers with 10 to 14 carbon atoms, such as dodecyl alcohol polyoxyethylene ether.

[0019] Preferably, the weight content of the straight-chain non-ionic surfactant in the slime flotation regulator is 1.1% - 1.5%, further preferably 1.2% - 1.4%, such as 1.2%, 1.25%, 1.3%, 1.35%, 1.4%.

[0020] Preferably, the zwitterionic surfactant containing an ester group is dodecyldimethylamine ethyl lactone.

[0021] Preferably, the weight content of the zwitterionic surfactant containing an ester group in the slime flotation regulator is 0.3% - 0.8%, further preferably 0.4% - 0.65%, such as 0.4%, 0.45%, 0.5%, 0.55%, 0.6%, 0.65%.

[0022] Preferably, the cationic surfactant is cetyltrimethylammonium bromide.

[0023] Preferably, the weight content of the cationic surfactant in the slime flotation regulator is 0.01% - 0.2%, further preferably 0.1% - 0.2%, such as 0.1%, 0.12%, 0.14%, 0.16%, 0.18%, 0.2%.

[0024] Preferably, the temperature of the ultrasonic treatment is 30°C - 50°C, and the time is 20 min - 40 min.

[0025] Further preferably, the temperature of the ultrasonic treatment is 35°C - 45°C, and the time is 25 min - 35 min.

[0026] Preferably, the temperature of the reaction is 50°C - 70°C, and the time is 20 min - 40 min.

[0027] Further preferably, the temperature of the reaction is 55°C to 65°C, and the time is 25 min to 35 min.

[0028] Preferably, the microwave action is carried out using a microwave hydrothermal parallel synthesizer, and the power of the microwave hydrothermal parallel synthesizer is 400 W to 600 W, more preferably 450 W to 550 W, such as 450 W, 480 W, 500 W, 530 W, 550 W.

[0029] Preferably, the dispersant is selected from one or more of inorganic sodium salts.

[0030] 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, exhibit a steric effect, increase the barrier effect between coal particles, keep the coal particles in a dispersed state, and they can also adjust the overall pH value of the system, and can be randomly embedded in the block toolbar with a longer action time.

[0031] Preferably, the weight content of the dispersant in the coal slime flotation regulator is 0.5% to 2%, more preferably 1% to 1.5%, such as 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%.

[0032] In some embodiments, the dispersant is sodium hexametaphosphate, sodium silicate, and sodium carbonate. The weight content of sodium hexametaphosphate in the coal slime flotation regulator is 0.35% to 1%, the weight content of sodium silicate in the coal slime flotation regulator is 0.1% to 0.3%, and the weight content of sodium carbonate in the coal slime flotation regulator is 0.05% to 0.2%.

[0033] Preferably, the emulsifier is selected from one or more of Tween and Span.

[0034] Preferably, the weight content of the emulsifier in the coal slime flotation regulator is 1% to 3%, more preferably 1.5% to 2.5%, such as 1.5%, 1.8%, 2%, 2.3%, 2.5%.

[0035] In some embodiments, the emulsifier is Tween and Span. The weight content of Tween in the coal slime flotation regulator is 0.8% to 1.5%, and the weight content of Span in the coal slime flotation regulator is 0.5% to 1%.

[0036] Preferably, based on the total weight of the coal slime flotation regulator being 100%, it comprises the following components:

[0037] Polysaccharide 5% to 12%;

[0038] Non-ionic surfactant containing a benzene ring: 1.4% - 1.9%;

[0039] Linear non-ionic surfactant: 1.1% - 1.5%;

[0040] Amphoteric surfactant containing an ester group: 0.3% - 0.8%;

[0041] Cationic surfactant: 0.01% - 0.2%;

[0042] Dispersant: 0.5% - 2%;

[0043] Emulsifier: 1% - 3%;

[0044] Water: the balance.

[0045] In some embodiments, based on the total weight of the coal slime flotation conditioner being 100%, it comprises the following components:

[0046] Polysaccharide: 5% - 12%;

[0047] Non-ionic surfactant containing a benzene ring: 1.4% - 1.9%;

[0048] Linear non-ionic surfactant: 1.1% - 1.5%;

[0049] Amphoteric surfactant containing an ester group: 0.3% - 0.8%;

[0050] Cationic surfactant: 0.01% - 0.2%;

[0051] Sodium hexametaphosphate: 0.35% - 1%;

[0052] Sodium silicate: 0.1% - 0.3%;

[0053] Sodium carbonate: 0.05% - 0.2%;

[0054] Tween: 0.8% - 1.5%;

[0055] Span: 0.5% - 1%;

[0056] Water: the balance.

[0057] Further preferably, based on the total weight of the coal slime flotation conditioner being 100%, it comprises the following components:

[0058] Polysaccharide: 7% - 10%;

[0059] Non-ionic surfactant containing a benzene ring: 1.6% - 1.8%;

[0060] Linear non-ionic surfactant: 1.2% - 1.4%;

[0061] 0.4% - 0.65% of zwitterionic surfactant containing ester group;

[0062] 0.1% - 0.2% of cationic surfactant;

[0063] 0.5% - 0.9% of sodium hexametaphosphate;

[0064] 0.15% - 0.3% of sodium silicate;

[0065] 0.1% - 0.15% of sodium carbonate;

[0066] 1% - 1.3% of Tween;

[0067] 0.6% - 0.8% of Span;

[0068] The balance is water.

[0069] Preferably, step (3) includes stirring and mixing the solution after the reaction in step (2) with the dispersant at 30°C - 50°C first, and then adding the emulsifier and stirring and mixing evenly at 40°C - 50°C.

[0070] More preferably, step (3) includes stirring and mixing the solution after the reaction in step (2) with the dispersant at 35°C - 45°C first, and then adding the emulsifier and stirring and mixing evenly at 43°C - 48°C.

[0071] In some embodiments, the rotation speed of the stirring is independently 100 r / min - 150 r / min, such as 100 r / min, 100 r / min, 120 r / min, 130 r / min, 150 r / min.

[0072] In some embodiments, the stirring and mixing time is independently 20 min - 40 min, such as 20 min, 25 min, 30 min, 35 min, 40 min.

[0073] On the other hand, the present invention provides a slime flotation regulator prepared by the preparation method as described above.

[0074] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0075] The present invention constructs a polysaccharide - surfactant block copolymer system through ultrasonic - microwave synthesis reaction. Through the synergistic effect of the block copolymer system with the dispersant and the emulsifier, the prepared regulator has good stability, long action time, strong selectivity, good flotation effect and wide application range. Description of the Drawings

[0076] Figure 1 This is a physical photo of some embodiments and some comparative examples of the present invention. Specific embodiments

[0077] The present invention will be further described below in conjunction with embodiments. However, the present invention is not limited to the following embodiments. The implementation conditions used in the embodiments can be further adjusted according to different requirements of specific use, and the implementation conditions not specified are conventional conditions in the industry. The technical features involved in various embodiments of the present invention can be combined with each other as long as they do not conflict with each other.

[0078] Unless otherwise specified, the raw materials and instruments involved hereinafter are commercially available products or can be prepared with reference to the prior art. Among them, oxidized starch is purchased from Shandong Zhucheng Xingmao Corn Development Co., Ltd., CAS No.: 65996-62-5; octylphenol polyoxyethylene ether is purchased from Sinopharm Chemical Reagent Co., Ltd., CAS No.: 9036-19-5; dodecyl alcohol polyoxyethylene ether is purchased from Sinopharm Chemical Reagent Co., Ltd., CAS No.: 9002-92-0. Example 1

[0079] This example provides a slime flotation regulator. Based on the total weight of the slime flotation regulator being 100%, it has: water 84.6 wt%, oxidized starch 8.7 wt%, octylphenol polyoxyethylene ether 1.7 wt%, dodecyl alcohol polyoxyethylene ether 1.3 wt%, dodecyldimethylamine inner salt 0.55 wt%, cetyltrimethylammonium bromide 0.15 wt%, sodium hexametaphosphate 0.77 wt%, sodium silicate 0.22 wt%, sodium carbonate 0.11 wt%, Tween 80 1.14 wt%, Span 60 0.76 wt%.

[0080] The preparation method of the slime flotation regulator includes the following steps:

[0081] (1) Dissolve oxidized starch in water, place it in an ultrasonic cell disruptor and perform ultrasonic treatment for 30 min at a temperature of 40 °C;

[0082] (2) Add octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, dodecyldimethylamine inner salt, and cetyltrimethylammonium bromide to the solution in step (1), place it in a microwave hydrothermal parallel synthesizer for reaction, with a microwave power of 500 W, a temperature of 60 °C, and a reaction time of 30 min;

[0083] (3) Add sodium hexametaphosphate, sodium silicate, and sodium carbonate to the solution in step (2), place it on a magnetic stirrer for stirring, with a stirring speed of 120 r / min, a temperature of 40 °C, and a time of 30 min;

[0084] (4) Add Tween 80 and Span 60 to the solution in step (3), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 45 °C, and a time of 30 min to obtain a slime flotation regulator. Example 2

[0085] This example provides a slime flotation regulator, and the preparation method is the same as that of Example 1, except that the oxidized starch in the slime flotation regulator is replaced with an equal weight of carboxymethyl cellulose. Example 3

[0086] This example provides a slime flotation regulator, and the preparation method is the same as that of Example 1, except that the oxidized starch in the slime flotation regulator is replaced with an equal weight of chitosan. Example 4

[0087] This example provides a slime flotation regulator, and the preparation method is the same as that of Example 1, except that the oxidized starch in the slime flotation regulator is replaced with an equal weight of arabic gum.

[0088] Comparative Example 1

[0089] This comparative example provides a slime flotation regulator. Based on the total weight of the slime flotation regulator being 100%, it has: 93.3 wt% of water, 1.7 wt% of octylphenol polyoxyethylene ether, 1.3 wt% of dodecyl alcohol polyoxyethylene ether, 0.55 wt% of lauryldimethylamine inner salt, 0.15 wt% of cetyltrimethylammonium bromide, 0.77 wt% of sodium hexametaphosphate, 0.22 wt% of sodium silicate, 0.11 wt% of sodium carbonate, 1.14 wt% of Tween 80, and 0.76 wt% of Span 60.

[0090] The preparation method of this slime flotation regulator includes the following steps:

[0091] (1) Preheat water to a temperature of 40 °C with a water bath.

[0092] (2) Add octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, lauryldimethylamine inner salt, and cetyltrimethylammonium bromide to the water in step (1), place it in a microwave hydrothermal parallel synthesizer for reaction, with a microwave power of 500 W, a temperature of 60 °C, and a reaction time of 30 min.

[0093] (3) Add sodium hexametaphosphate, sodium silicate, and sodium carbonate to the solution in step (2), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 40 °C, and a time of 30 min.

[0094] (4) Add Tween 80 and Span 60 to the solution in step (3), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 45 °C, and for a time of 30 min to obtain a slime flotation conditioner without polysaccharides.

[0095] Comparative Example 2

[0096] This comparative example provides a slime flotation conditioner. Based on the total weight of the slime flotation conditioner being 100%, it has: 91.3 wt% of water and 8.7 wt% of oxidized starch.

[0097] The preparation method of this slime flotation conditioner includes subjecting oxidized starch to ultrasonic treatment in an ultrasonic cell disruptor for 30 min at a temperature of 40 °C, and after the treatment, a slime flotation inhibitor containing only oxidized starch is obtained.

[0098] Comparative Example 3

[0099] This comparative example provides a slime flotation conditioner. The preparation method is the same as that of Comparative Example 2, with the only difference being that oxidized starch is replaced with an equal weight of carboxymethyl cellulose.

[0100] Comparative Example 4

[0101] This comparative example provides a slime flotation conditioner. The preparation method is the same as that of Comparative Example 2, with the only difference being that oxidized starch is replaced with an equal weight of chitosan.

[0102] Comparative Example 5

[0103] This comparative example provides a slime flotation conditioner. The preparation method is the same as that of Comparative Example 2, with the only difference being that oxidized starch is replaced with an equal weight of arabic gum.

[0104] Comparative Example 6

[0105] This comparative example provides a slime flotation conditioner. Based on the total weight of the slime flotation conditioner being 100%, it has: 88.3 wt% of water, 8.7 wt% of oxidized starch, 0.77 wt% of sodium hexametaphosphate, 0.22 wt% of sodium silicate, 0.11 wt% of sodium carbonate, 1.14 wt% of Tween 80, and 0.76 wt% of Span 60.

[0106] The preparation method of this slime flotation conditioner includes the following steps:

[0107] (1) Dissolve oxidized starch in water, place it in an ultrasonic cell disruptor and perform ultrasonic treatment for 30 min at a temperature of 40 °C;

[0108] (2) Add sodium hexametaphosphate, sodium silicate, and sodium carbonate to the solution in step (1), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 40 °C, and for a time of 30 min;

[0109] (3) Add Tween 80 and Span 60 to the solution in step (2), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 45 °C, and for a time of 30 min to obtain a slime flotation conditioner without surfactant.

[0110] Comparative Example 7

[0111] This comparative example provides a slime flotation conditioner. Based on the total weight of the slime flotation conditioner being 100%, it has: water 85.7 wt%, oxidized starch 8.7 wt%, octylphenol polyoxyethylene ether 1.7 wt%, lauryl alcohol polyoxyethylene ether 1.3 wt%, lauryl dimethylamine ethylene lactone 0.55 wt%, cetyltrimethylammonium bromide 0.15 wt%, Tween 80 1.14 wt%, and Span 60 0.76 wt%.

[0112] The preparation method of this slime flotation conditioner includes the following steps:

[0113] (1) Dissolve oxidized starch in water, place it in an ultrasonic cell disruptor and ultrasonically treat for 30 min at a temperature of 40 °C;

[0114] (2) Add octylphenol polyoxyethylene ether, lauryl alcohol polyoxyethylene ether, lauryl dimethylamine ethylene lactone, and cetyltrimethylammonium bromide to the solution in step (1), place it in a microwave hydrothermal parallel synthesizer and react at a microwave power of 500 W, a temperature of 60 °C, and a reaction time of 30 min;

[0115] (3) Add Tween 80 and Span 60 to the solution in step (2), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 45 °C, and for a time of 30 min to obtain a slime flotation conditioner without dispersant.

[0116] Comparative Example 8

[0117] This comparative example provides a slime flotation conditioner. Based on the total weight of the slime flotation conditioner being 100%, it has: water 86.5 wt%, oxidized starch 8.7 wt%, octylphenol polyoxyethylene ether 1.7 wt%, lauryl alcohol polyoxyethylene ether 1.3 wt%, lauryl dimethylamine ethylene lactone 0.55 wt%, cetyltrimethylammonium bromide 0.15 wt%, sodium hexametaphosphate 0.77 wt%, sodium silicate 0.22 wt%, and sodium carbonate 0.11 wt%.

[0118] The preparation method of this slime flotation conditioner includes the following steps:

[0119] (1) Dissolve oxidized starch in water, place it in an ultrasonic cell disruptor and ultrasonically treat for 30 min at a temperature of 40 °C;

[0120] (2) Add octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, dodecyl dimethylamine ethyl lactone, and cetyltrimethylammonium bromide to the solution in step (1), place it in a microwave hydrothermal parallel synthesizer for reaction, with a microwave power of 500 W, a temperature of 60 °C, and a reaction time of 30 min;

[0121] (3) Add sodium hexametaphosphate, sodium silicate, and sodium carbonate to the solution in step (2), place it on a magnetic stirrer for stirring, with a stirring speed of 120 r / min, a temperature of 40 °C, and a time of 30 min to obtain a coal slime flotation regulator without emulsifier.

[0122] Comparative Example 9

[0123] This comparative example provides a coal slime flotation regulator, which is basically the same as Example 1, except for the different preparation methods.

[0124] The preparation method of the coal slime flotation regulator in this comparative example is: mix each component according to the specified weight ratio, and stir well to obtain a coal slime flotation regulator without a reaction process.

[0125] Comparative Example 10

[0126] This comparative example provides a coal slime flotation regulator. Based on the total weight of the coal slime flotation regulator being 100%, it has: water 84.6 wt%, oxidized starch 8.7 wt%, octylphenol polyoxyethylene ether 1.7 wt%, dodecyl alcohol polyoxyethylene ether 1.3 wt%, dodecyl dimethylamine ethyl lactone 0.7 wt%, sodium hexametaphosphate 0.77 wt%, sodium silicate 0.22 wt%, sodium carbonate 0.11 wt%, Tween 80 1.14 wt%, Span 60: 0.76 wt%.

[0127] The preparation method of this coal slime flotation regulator includes the following steps:

[0128] (1) Dissolve oxidized starch in water, place it in an ultrasonic cell disruptor for ultrasonic treatment for 30 min, at a temperature of 40 °C;

[0129] (2) Add octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, and dodecyl dimethylamine ethyl lactone to the solution in step (1), place it in a microwave hydrothermal parallel synthesizer for reaction, with a microwave power of 500 W, a temperature of 60 °C, and a reaction time of 30 min;

[0130] (3) Add sodium hexametaphosphate, sodium silicate, and sodium carbonate to the solution in step (2), place it on a magnetic stirrer for stirring, with a stirring speed of 120 r / min, a temperature of 40 °C, and a time of 30 min;

[0131] (4) Add Tween 80 and Span 60 to the solution in step (3), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 45 °C, and for a time of 30 min to obtain a coal slime flotation modifier.

[0132] Comparative Example 11

[0133] This comparative example provides a coal slime flotation modifier. Based on the total weight of the coal slime flotation modifier being 100%, it has: water 84.6 wt%, oxidized starch 8.7 wt%, octylphenol polyoxyethylene ether 1.7 wt%, dodecyl alcohol polyoxyethylene ether 1.3 wt%, cetyltrimethylammonium bromide 0.7 wt%, sodium hexametaphosphate 0.77 wt%, sodium silicate 0.22 wt%, sodium carbonate 0.11 wt%, Tween 80 is 1.14 wt%, and Span 60 is 0.76 wt%.

[0134] The preparation method of this coal slime flotation modifier includes the following steps:

[0135] (1) Dissolve oxidized starch in water, place it in an ultrasonic cell disruptor and perform ultrasonic treatment for 30 min at a temperature of 40 °C;

[0136] (2) Add octylphenol polyoxyethylene ether, dodecyl alcohol polyoxyethylene ether, and cetyltrimethylammonium bromide to the solution in step (1), place it in a microwave hydrothermal parallel synthesizer and react at a microwave power of 500 W, a temperature of 60 °C, and a reaction time of 30 min;

[0137] (3) Add sodium hexametaphosphate, sodium silicate, and sodium carbonate to the solution in step (2), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 40 °C, and for a time of 30 min;

[0138] (4) Add Tween 80 and Span 60 to the solution in step (3), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 45 °C, and for a time of 30 min to obtain a coal slime flotation modifier.

[0139] Comparative Example 12

[0140] This comparative example provides a coal slime flotation modifier. Based on the total weight of the coal slime flotation modifier being 100%, it has: water 84.6 wt%, oxidized starch 8.7 wt%, octylphenol polyoxyethylene ether 3 wt%, dodecyldimethylamine ethoxylate 0.55 wt%, cetyltrimethylammonium bromide 0.15 wt%, sodium hexametaphosphate 0.77 wt%, sodium silicate 0.22 wt%, sodium carbonate 0.11 wt%, Tween 80 is 1.14 wt%, and Span 60: 0.76 wt%.

[0141] The preparation method of this coal slime flotation modifier includes the following steps:

[0142] (1) Dissolve oxidized starch in water, place it in an ultrasonic cell disruptor for ultrasonic treatment for 30 min at a temperature of 40 °C;

[0143] (2) Add octylphenol polyoxyethylene ether, lauryldimethylamine acetolactone, and cetyltrimethylammonium bromide to the solution in step (1), place it in a microwave hydrothermal parallel synthesizer for reaction, with a microwave power of 500 W, a temperature of 60 °C, and a reaction time of 30 min;

[0144] (3) Add sodium hexametaphosphate, sodium silicate, and sodium carbonate to the solution in step (2), place it on a magnetic stirrer for stirring, with a stirring speed of 120 r / min, a temperature of 40 °C, and a time of 30 min;

[0145] (4) Add Tween 80 and Span 60 to the solution in step (3), place it on a magnetic stirrer for stirring, with a stirring speed of 120 r / min, a temperature of 45 °C, and a time of 30 min to obtain a slime flotation regulator.

[0146] Comparative Example 13

[0147] This comparative example provides a slime flotation regulator. Based on the total weight of the slime flotation regulator being 100%, it has: water 84.6 wt%, oxidized starch 8.7 wt%, octylphenol polyoxyethylene ether 0.925 wt%, lauryl alcohol polyoxyethylene ether 0.925 wt%, lauryldimethylamine acetolactone 0.925 wt%, cetyltrimethylammonium bromide 0.925 wt%, sodium hexametaphosphate 0.77 wt%, sodium silicate 0.22 wt%, sodium carbonate 0.11 wt%, Tween 80 1.14 wt%, and Span 60 0.76 wt%.

[0148] The preparation method of this slime flotation regulator includes the following steps:

[0149] (1) Dissolve oxidized starch in water, place it in an ultrasonic cell disruptor for ultrasonic treatment for 30 min at a temperature of 40 °C;

[0150] (2) Add octylphenol polyoxyethylene ether, lauryl alcohol polyoxyethylene ether, lauryldimethylamine acetolactone, and cetyltrimethylammonium bromide to the solution in step (1), place it in a microwave hydrothermal parallel synthesizer for reaction, with a microwave power of 500 W, a temperature of 60 °C, and a reaction time of 30 min;

[0151] (3) Add sodium hexametaphosphate, sodium silicate, and sodium carbonate to the solution in step (2), place it on a magnetic stirrer for stirring, with a stirring speed of 120 r / min, a temperature of 40 °C, and a time of 30 min;

[0152] (4) Add Tween 80 and Span 60 to the solution in step (3), place it on a magnetic stirrer and stir at a stirring speed of 120 r / min, a temperature of 45 °C, and a time of 30 min to obtain a slime flotation regulator.

[0153] Test the effect of the slime flotation regulator through flotation unit experiments:

[0154] The evaluation of the flotation effect in flotation unit experiments is mainly based on the following indicators: clean coal yield, clean coal ash content, tailing ash content, and flotation perfection index. Among them, the clean coal yield is the ratio of the mass of the clean coal scraped after flotation to the total feed mass of the flotation coal powder before flotation, expressed as a percentage, and the larger the clean coal yield value, the better; the clean coal ash content and the tailing ash content are determined in accordance with the "Proximate Analysis of Coal" (GB / T 212 - 2008), and the smaller the clean coal ash content value, the better; the flotation perfection index is determined in accordance with the "Evaluation Method for Flotation Process Effect in Coal Preparation Plants" (GB / T 34164 - 2017), and the larger the flotation perfection index value, the better.

[0155] Conduct flotation unit experiments on the above slime flotation regulator. The flotation experiment method refers to the "Laboratory Unit Flotation Test Method for Coal Powder (Slime)" (GB / T 4757 - 2013) for performance detection. The slime flotation regulator (i.e., the regulator) is added after stirring and slurrying for 2 min, and then the collector and foaming agent are added. The collector is selected as 0# diesel, and the foaming agent is selected as sec - octanol. The group without adding the regulator is used as the control group. The flotation machine uses a 1.5L XFD - type single - cell flotation machine, and the impeller speed of the flotation machine is set at 1800 r / min, and the unit gas - injection volume is 0.25 m 3 / (m 2 •min). The pulp concentration is 80 g / L, the dosage of the regulator is 500 g / t of dry slime, the dosage of the collector is 800 g / t of dry slime, and the dosage of the foaming agent is 100 g / t of dry slime.

[0156] Coking coal experiment:

[0157] Select different coal types for experiments. First, select 1 / 3 coking coal slime, sampled from Linhuan Coal Preparation Plant of Huaibei Mining Industry. The ash content of the flotation feed is 29.29%. After the slime is dried, crushed, screened, blended, and reduced, an analytical coal sample with a particle size less than 0.5 mm is prepared in accordance with the "Method for Preparation of Coal Samples" (GB / T474 - 2008). The flotation test results are shown in Table 1.

[0158] Table 1

[0159]

[0160] As can be seen from Table 1, the clean coal yield of the control group without the modifier was 64.35%, the ash content of the clean coal was 11.33%, the ash content of the tailings was 60.22%, and the flotation perfection index was 54.74%. By adding the modifier prepared in the examples of the present invention, the clean coal yield can be increased by 2.99 - 4.54 percentage points, the ash content of the clean coal can be reduced by 0.78 - 0.95 percentage points, the ash content of the tailings can be increased by 4.75 - 5.89 percentage points, and the flotation perfection index can be increased by 4.28 - 4.86 percentage points, indicating that the addition of the modifier significantly improves the flotation effect.

[0161] By comparing Examples 1 to 4 of the present invention and Comparative Example 1, it was found that when the modifier did not contain polysaccharide, the improvement of the modifier on the flotation effect was limited. Except that the clean coal yield was slightly higher than that of the control group, other indicators were comparable to those of the control group, and the overall flotation effect was inferior to that of the present invention.

[0162] By comparing Examples 1 to 4 of the present invention and Comparative Examples 2 to 5, it was found that when the modifier only contained polysaccharide and did not contain surfactant, emulsifier, and dispersant, compared with the control group in Comparative Examples 2 to 5, the ash content of the clean coal was significantly reduced, but the clean coal yield and the flotation perfection index were also greatly reduced, indicating that the modifier containing only polysaccharide had an obvious inhibitory effect, but at the same time, it would also cause excessive inhibition and reduce economic benefits.

[0163] By comparing Example 1 of the present invention and Comparative Example 6, it was found that when the modifier did not contain surfactant, although the ash content of the clean coal was lower than that of the control group, the clean coal yield and the flotation perfection index were not high, and were inferior to Example 1 of the present invention.

[0164] By comparing Example 1 of the present invention and Comparative Example 7, it was found that when the modifier did not contain dispersant, the ash content of the clean coal and the ash content of the tailings did not change significantly compared with the control group, and the overall flotation perfection index was inferior to Example 1 of the present invention.

[0165] By comparing Example 1 of the present invention and Comparative Example 8, it was found that when the modifier did not contain emulsifier, although the clean coal yield increased and the ash content of the clean coal decreased, the flotation perfection index was inferior to Example 1 of the present invention.

[0166] By comparing Example 1 of the present invention and Comparative Example 9, it was found that for the modifier prepared by directly mixing the raw materials without ultrasonic and microwave reactions, whether it was the clean coal yield, the ash content of the clean coal, or the flotation perfection index, they were all inferior to the examples of the present application. The present invention constructs a "polysaccharide - surfactant" block copolymer system through ultrasonic - microwave synthesis reaction, and carries a dispersant, etc., which can form a modifier with better flotation effect, more stability and longer action time.

[0167] By comparing the examples of the present invention with Comparative Examples 10 to 13, the present invention improves the flotation effect of the regulator by using a cationic surfactant, an amphoteric surfactant containing an ester group, a nonionic surfactant containing a benzene ring, and a linear nonionic surfactant in combination, and by adjusting the dosages of various surfactants.

[0168] Experiment on high-ash fat coal:

[0169] Select high-ash fat coal slime, sampled from Linhuan Coal Preparation Plant of Huaibei Mining Industry. The ash content of the flotation feed is 30.52%. After the coal slime is dried, crushed, screened, blended, and reduced in size, an analytical coal sample with a particle size less than 0.5 mm is prepared according to the "Method for Preparation of Coal Samples" (GB / T 474-2008). The flotation test results are shown in Table 2.

[0170] Table 2

[0171]

[0172] 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 is 48.67%, the ash content of the clean coal is 12.3%, the ash content of the tailings is 51.33%, and the flotation perfection index is 46.07%. By adding the regulators of Examples 1 to 4 of the present invention, the overall clean coal yield is increased by about 10 percentage points, the ash content of the clean coal is reduced by about 1 percentage point, the ash content of the tailings is increased by about 12 percentage points, and the flotation perfection index is increased by about 14 percentage points, indicating that the addition of the regulator significantly improves the flotation effect. Similarly, the flotation effects of the regulators in Comparative Examples 1 to 13 are all inferior to those of the examples of the present invention.

[0173] Stability experiment:

[0174] Perform a room-temperature storage stability experiment on Examples 1 to 4 and Comparative Examples 8 and 9. After preparing each sample, place it at room temperature (25 ± 5 °C) for 1 week and observe its stability. The results are as Figure 1 shown. It can be Figure 1 seen that Examples 1 to 4 are in a homogeneous state as a whole, without stratification or precipitation; there is a small amount of clear liquid separated out in the upper layer of Comparative Example 8, and there is obvious precipitation in Comparative Example 9. Their stabilities are all inferior to those of Examples 1 to 4.

[0175] The above has described the present invention in detail. The purpose is to enable those skilled in this field to understand the content of the present invention and implement it, but it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within 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 1.6% to 1.8%; 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 regulator 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 1.6%~1.8%; 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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