Method for purifying kaolin concentrate, application of kaolin concentrate and building mortar

Abstract

The invention relates to the field of coal gangue, and discloses a method for purifying kaolin concentrate, application of the kaolin concentrate and building mortar. The method comprises the steps that 1, coal gangue ore pulp makes contact with an acid solution I to adjust the pH value of the coal gangue ore pulp, and first ore pulp with the pH value being 5-6 is obtained; the coal gangue ore pulp is formed by contacting coal gangue with water; 2, the first ore pulp makes contact with a mixed collecting agent I for first roughing treatment, and first kaolin concentrate and tailing ore pulp I are obtained; the mixed collecting agent I is composed of saponified oleic acid and petroleum sodium sulfonate according to the weight ratio of 1: (0.2-0.8); 3, the tailing pulp I makes contact with a mixed collecting agent II for first scavenging treatment, and second kaolin concentrate is obtained; the mixed collecting agent II is composed of saponified oleic acid and petroleum sodium sulfonate according to the weight ratio of 1: (0.1-0.8). The kaolin concentrate obtained through purification of the method is high in purity and high in purification recovery rate.

Description

Technical Field

[0001] The invention relates to the technical field of gangue treatment, and in particular to a method for purifying kaolin concentrate and application thereof, and a building mortar. Background Art

[0002] Gangue is a kind of waste rock associated with coal. It is discharged during the coal mining and sorting process. Its emission is equivalent to 15%-20% of the raw coal output. Gangue is the largest industrial solid waste in my country, with an accumulated amount of nearly 5 billion tons. The continuous generation and long-term open-air storage of gangue not only occupies a large amount of arable land and forest land, but also pollutes the air, surrounding soil and groundwater. my country began to carry out the comprehensive utilization of gangue resources in power generation, brick making, reclamation, filling and road construction from the 1950s and 1960s. At present, the overall utilization rate of gangue is about 65%.

[0003] Kaolin has good plasticity and fire resistance, and is mainly used in papermaking, ceramics, refractory materials, coatings, rubber fillers, plastics, medicine, textiles, chemicals, building materials and other industries. Using coal gangue to purify and burn kaolin can greatly improve the utilization efficiency of coal gangue resources, increase its added value, and the economic benefits are very obvious; at the same time, the rational use of coal gangue resources will bring huge economic and social benefits to the city.

[0004] CN104475235A discloses a method for purifying low-grade kaolin ore, which comprises crushing the raw ore three times, then grinding it, and performing three-stage spiral separation of the mineral after the grinding operation using a spiral classifier and a cyclone, and then adding sulfuric acid, butyl xanthate and 2# oil to the separated material for pyrite flotation, and performing two-stage magnetic separation, and then performing mica flotation using sulfuric acid and dodecylamine after magnetic separation, and then performing cyclone classification after flotation, so as to obtain two finished ore powders of kaolin ore concentrate quality; however, this scheme has the problems of low purification purity and low recovery rate of kaolin. Summary of the invention

[0005] The purpose of the invention is to overcome the problems of low purification purity and poor recovery rate of kaolin purified from coal gangue.

[0006] In order to achieve the above object, the first aspect of the present invention provides a method for purifying a kaolin concentrate product, the method comprising:

[0007] (1) contacting a coal gangue slurry with an acid solution I to adjust the pH value of the coal gangue slurry to obtain a first slurry with a pH value of 5-6; the coal gangue slurry is formed by contacting coal gangue with water;

[0008] (2) contacting the first slurry with a mixed collector I to perform a first roughing treatment to obtain a first kaolin concentrate and tailings slurry I; the mixed collector I is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.2-0.8;

[0009] (3) contacting the tailings slurry I with a mixed collector II to perform a first scavenging treatment to obtain a second kaolin concentrate and tailings slurry II; the mixed collector II is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.1-0.8;

[0010] The first kaolin concentrate and / or the second kaolin concentrate can be used as the kaolin concentrate product.

[0011] The second aspect of the present invention provides the use of kaolin concentrate purified by the method described in the first aspect in building mortar.

[0012] The third aspect of the present invention provides a building mortar, which contains calcined kaolin, limestone sand, coal gangue sand, cement, filler, cellulose ether, starch ether and water; the calcined kaolin is a product obtained by roasting kaolin concentrate;

[0013] The kaolin concentrate is the kaolin concentrate product obtained by the method described in the first aspect.

[0014] Preferably, for every 100 parts by weight of gangue sand, the amount of calcined kaolin is 4-12 parts by weight, the amount of limestone sand is 240-245 parts by weight, the amount of cement is 45-55 parts by weight, the amount of filler is 30-38 parts by weight, the amount of cellulose ether is 0.06-0.12 parts by weight, the amount of starch ether is 0.01-0.04 parts by weight and the amount of water is 65-80 parts by weight.

[0015] Preferably, the calcination treatment is carried out at a temperature of 600-900°C and for a time of 1-5 hours.

[0016] Compared with the prior art, the present invention has at least the following advantages: the kaolin concentrate purified by the method of the present invention has high purity and high purification recovery rate. DETAILED DESCRIPTION

[0017] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0018] As mentioned above, the first aspect of the present invention provides a method for purifying a kaolin concentrate product, the method comprising:

[0019] (1) contacting a coal gangue slurry with an acid solution I to adjust the pH value of the coal gangue slurry to obtain a first slurry with a pH value of 5-6; the coal gangue slurry is formed by contacting coal gangue with water;

[0020] (2) contacting the first slurry with a mixed collector I to perform a first roughing treatment to obtain a first kaolin concentrate and tailings slurry I; the mixed collector I is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.2-0.8;

[0021] (3) contacting the tailings slurry I with a mixed collector II to perform a first scavenging treatment to obtain a second kaolin concentrate and tailings slurry II; the mixed collector II is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.1-0.8;

[0022] The first kaolin concentrate and / or the second kaolin concentrate can be used as the kaolin concentrate product.

[0023] Preferably, the method further comprises step (4): contacting the tailings slurry II with an acid solution II to adjust the pH value of the tailings slurry II to obtain a second slurry with a pH value of 2-3; and contacting the second slurry with an amine cationic collector to sequentially perform a second roughing treatment and at least one second scavenging treatment to obtain a mixed concentrate and a third kaolin concentrate; the mixed concentrate contains quartz and feldspar, and at least one of the first kaolin concentrate, the second kaolin concentrate and the third kaolin concentrate can be used as the kaolin concentrate product.

[0024] Further preferably, the total amount of the amine cationic collector used is 10-100 g per 1 ton of the coal gangue.

[0025] More preferably, the amine cationic collector is dodecylamine and / or octadecylamine.

[0026] According to a preferred embodiment, the number of times of the second scanning process is ≥2 times. Exemplarily, the operation of performing the second scavenging treatment twice is provided, specifically: after the second slurry is contacted with the amine cationic collector for the second roughing treatment, a third kaolin concentrate-1 and a tailings slurry III containing quartz and feldspar are obtained, the tailings slurry III is contacted with the amine cationic collector for the first second scavenging treatment to obtain a third kaolin concentrate-2 and a tailings slurry IV containing quartz and feldspar, the tailings slurry IV is contacted with the amine cationic collector for the second second scavenging treatment to obtain a third kaolin concentrate-3 and a tailings slurry V containing quartz and feldspar, and the tailings slurry V is filtered and dried to obtain the mixed concentrate containing quartz and feldspar; at least one of the third kaolin concentrate-1, the third kaolin concentrate-2 and the third kaolin concentrate-3 can be used as the third kaolin concentrate; the method of filtering and drying treatment adopts the conventional manner in the art, and those skilled in the art should not be understood as limiting the present invention.

[0027] Particularly preferably, the amount of the mixed collector I used is 300-800 g per 1 ton of the coal gangue.

[0028] Preferably, the weight ratio of the mixed collector I to the mixed collector II is 1:0.1-1.5.

[0029] It should be noted that in order to effectively disperse the collector in the ore pulp and fully exert its corresponding effect, the mixed collector I, the mixed collector II and the amine cationic collector need to be contacted and reacted with the ore pulp in the form of liquid; among them, if the collector is a substance soluble in water, such as saponified oleic acid and sodium petroleum sulfonate, the collector is dissolved in water and reacts with the ore pulp in the form of an aqueous solution; if the collector is a substance insoluble in water, such as octadecylamine and dodecylamine, it is made into a corresponding water-soluble salt and then reacts with the ore pulp in the form of an aqueous solution.

[0030] Preferably, the conditions of the first roughing treatment include: temperature of 10-40°C, time of 3-5 min; the conditions of the first sweeping treatment include: temperature of 10-40°C, time of 1-3 min.

[0031] Preferably, the conditions of the second roughing treatment include: temperature of 10-40°C, time of 3-5 min; the conditions of the second sweeping treatment include: temperature of 10-40°C, time of 1-3 min.

[0032] According to a preferred embodiment, the coal gangue contains 40-58wt% kaolin, 30-40wt% quartz, 10-20wt% feldspar, 0.5-1.5wt% siderite, 0.1-1wt% calcite, 0.1-0.6wt% pyrite and 0.1-0.5wt% dolomite. The inventors of the present invention have found that under this preferred condition, the purified kaolin has high purity and high recovery rate.

[0033] Preferably, the gangue slurry is an aqueous solution with a concentration of 25-35wt%.

[0034] Preferably, in step (1), the gangue used to form the gangue slurry is gangue powder, and the particle size of the gangue powder is less than 75 μm. The inventors of the present invention have found that under this preferred condition, the purified kaolin has high purity and high recovery rate.

[0035] According to a preferred embodiment, the gangue powder is prepared by a method comprising the following steps: performing a first crushing treatment on the gangue to obtain gangue I with a particle size of less than 40 mm, and performing a second crushing treatment on the gangue I to obtain 75-77wt% of gangue sand with a particle size of 0.075mm-2.36mm and 23-25wt% of the gangue powder with a particle size of less than 75μm;

[0036] The first crushing process is performed by using a jaw crusher or an impact crusher;

[0037] The second crushing process is carried out by a vertical shaft crusher, and the coal gangue feed rate of the vertical shaft crusher is 60-80t / h, the rotor speed is 900-1200rpm, and the motor power is 240-320KW. The inventors of the present invention have found that under this preferred condition, kaolin can be effectively enriched in the coal gangue powder with a particle size of <75μm, so that the purification purity of kaolin is high and the purification recovery rate is high; and under this preferred condition, the coal gangue is crushed into 75-77wt% of the particle size of

[0038] The gangue sand of 0.075mm-2.36mm and the gangue powder of 23-25wt% with a particle size of <75μm, the gangue sand can be directly used in building mortar, and the gangue powder can be used to purify kaolin. This method can effectively and comprehensively utilize the gangue, and the comprehensive utilization has low cost and high efficiency.

[0039] Preferably, the method further comprises: subjecting the first kaolin concentrate and / or the second kaolin concentrate to magnetic separation to obtain a kaolin concentrate product that can be used as the kaolin concentrate product.

[0040] Further preferably, the magnetic field strength of the magnetic separation is 1.0-1.3T.

[0041] More preferably, the method further comprises subjecting the first kaolin concentrate, the second kaolin concentrate and the third kaolin concentrate to the magnetic separation to obtain a kaolin concentrate product.

[0042] It should be noted that the first kaolin concentrate obtained by the first roughing treatment in step (2) of the present invention, the second kaolin concentrate obtained by the first scavenging treatment in step (3), the third kaolin concentrate and the mixed concentrate obtained by the second roughing treatment and the second scavenging treatment in step (4) are all concentrates subjected to filtration and drying treatment, and the filtration and drying treatment method is a conventional means adopted by those skilled in the art, which should not be construed as a limitation to the present invention.

[0043] As mentioned above, the second aspect of the present invention provides the use of kaolin concentrate purified by the method described in the first aspect in building mortar.

[0044] As mentioned above, the third aspect of the present invention provides a building mortar, which contains calcined kaolin, limestone sand, coal gangue sand, cement, filler, cellulose ether, starch ether and water; the calcined kaolin is a product obtained by roasting kaolin concentrate;

[0045] The kaolin concentrate is the kaolin concentrate product obtained by the method described in the first aspect.

[0046] Preferably, for every 100 parts by weight of gangue sand, the amount of calcined kaolin is 4-12 parts by weight, the amount of limestone sand is 240-245 parts by weight, the amount of cement is 45-55 parts by weight, the amount of filler is 30-38 parts by weight, the amount of cellulose ether is 0.06-0.12 parts by weight, the amount of starch ether is 0.01-0.04 parts by weight and the amount of water is 65-80 parts by weight.

[0047] Preferably, the calcination treatment is carried out at a temperature of 600-900°C and for a time of 1-5 hours.

[0048] The calculation method of the purification purity in the present invention: MLA mineral parameter automatic quantitative analyzer.

[0049] The calculation method of the purification recovery rate in the present invention is: kaolin content in kaolin concentrate / kaolin content in raw material.

[0050] Coal gangue: 48.9wt% kaolin, 34.3wt% quartz, 15.1wt% feldspar, 1.0wt% siderite, 0.4wt% calcite, 0.2wt% pyrite and 0.1wt% dolomite.

[0051] In the following examples, unless otherwise specified, all raw materials involved were commercially available analytically pure products.

[0052] Saponified oleic acid: Model PX-K90F was purchased from Zibo Pengxin Chemical Technology Co., Ltd.

[0053] Sodium petroleum sulfonate: Model T702, purchased from Jinan Bio Chemical Co., Ltd.

[0054] Octadecanamine: Model 124-30-1, purchased from Hubei Jusheng Technology Co., Ltd.

[0055] Cellulose ether: Model LH40M, purchased from Northern Tianpu Cellulose Co., Ltd.

[0056] Starch ether: model CASUCOL301, purchased from Avibe (China) Co., Ltd. of the Netherlands.

[0057] Preparation Example 1

[0058] The gangue is crushed by a jaw crusher to obtain a gangue I with a particle size of less than 40 mm, and the gangue I is crushed by a vertical shaft crusher to obtain 75 wt% of gangue sand with a particle size of 0.075 mm to 2.36 mm and 25 wt% of gangue powder with a particle size of less than 75 μm;

[0059] The coal gangue feed capacity of the vertical shaft crusher is 70t / h, the rotor speed is 1160rpm, and the motor power is 300KW.

[0060] Preparation Example 2

[0061] 1. Mixed collector I-1: saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.5;

[0062] Take 6.7 g of saponified oleic acid and 3.3 g of sodium petroleum sulfonate and dissolve them in 1 L of water to obtain solution 1;

[0063] 2. Mixed collector II-1: saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.1;

[0064] Take 9.1 g of saponified oleic acid and 0.9 g of sodium petroleum sulfonate and dissolve them in 1 L of water to obtain solution 2;

[0065] 3. Amine cationic collector: octadecylamine;

[0066] Take 10 g of octadecylamine and 10 mL of acetic acid and mix them to obtain octadecylamine acetate, and dissolve the octadecylamine acetate in 1 L of water to obtain solution 3;

[0067] 4. Mixed collector I-2: saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.2;

[0068] Take 8.3 g of saponified oleic acid and 1.7 g of sodium petroleum sulfonate and dissolve them in 1 L of water to obtain solution 4;

[0069] 5. Mixed collector II-2: saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.7;

[0070] Take 5.9 g of saponified oleic acid and 4.1 g of sodium petroleum sulfonate and dissolve them in 1 L of water to obtain solution 5;

[0071] 6. Mixed collector II-3: saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:2;

[0072] 3.3 g of saponified oleic acid and 6.7 g of sodium petroleum sulfonate were dissolved in 1 L of water to obtain Solution 6.

[0073] Example 1

[0074] (1) contacting 1 kg of the coal gangue powder with a particle size of less than 75 μm obtained in Preparation Example 1 with water to obtain a coal gangue slurry with a concentration of 30 wt %;

[0075] (2) contacting and mixing the gangue slurry with hydrochloric acid to obtain a first slurry with a pH of 5;

[0076] (3) taking 50 mL of the solution 1 prepared in Preparation Example 2 and contacting it with the first slurry to perform a first roughing treatment, thereby obtaining a flotation foam I containing a first kaolin concentrate and a tailings slurry I (i.e., the amount of the mixed collector I-1 is 500 g per ton of coal gangue powder, wherein the mixed collector I-1 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.5), and performing a first filtration and drying treatment on the flotation foam I containing the first kaolin concentrate to obtain a first kaolin concentrate;

[0077] The first filtering and drying treatment comprises: washing and filtering the flotation foam I with water, and drying the filtered product at 105° C. for 60 minutes;

[0078] The first roughing treatment was performed at a temperature of 28°C and for 5 minutes;

[0079] (4) taking 30 mL of the solution 2 prepared in Preparation Example 2 and contacting it with the tailings slurry I to perform a first scavenging treatment to obtain a flotation foam II containing a second kaolin concentrate and a tailings slurry II (i.e., the amount of the mixed collector II-1 is 300 g per ton of coal gangue powder, and the weight ratio of the mixed collector I-1 to the mixed collector II-1 is 1:0.6, wherein the mixed collector II-1 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.1), and performing a second filtration and drying treatment on the flotation foam II containing the second kaolin concentrate to obtain a second kaolin concentrate;

[0080] The second filtering and drying process includes: washing and filtering the flotation foam II with water, and drying the filtered product at 105° C. for 60 minutes;

[0081] The temperature of the first sweep treatment was 28°C and the time was 3 minutes;

[0082] (5) contacting and mixing the tailings slurry II with hydrochloric acid to obtain a second slurry with a pH of 2;

[0083] (6) 4 mL of the solution 3 prepared in Preparation Example 2 was contacted with the second slurry for a second roughing treatment to obtain a flotation foam III containing the third kaolin concentrate-1 and a tailings slurry III containing quartz and feldspar, 2 mL of the solution 3 prepared in Preparation Example 2 was contacted with the tailings slurry III for a first second scavenging treatment to obtain a flotation foam IV containing the third kaolin concentrate-2 and a tailings slurry IV containing quartz and feldspar, 2 mL of the solution 3 prepared in Preparation Example 2 was contacted with the tailings slurry IV for a second second scavenging treatment to obtain a flotation foam V containing the third kaolin concentrate-3 and a tailings slurry V containing quartz and feldspar (i.e., the total amount of octadecylamine used was 80 g per ton of coal gangue powder), and the flotation foam III, the flotation foam IV, and the flotation foam V were subjected to a third filtration and drying treatment to obtain a third kaolin concentrate, and the tailings slurry V was subjected to a third filtration and drying treatment to obtain a feldspar mixed concentrate;

[0084] The third filtering and drying treatment includes: washing and filtering the flotation foam and the tailings pulp V with water, and drying the filtered products at 105° C. for 60 minutes;

[0085] The second roughing treatment was performed at a temperature of 28°C and for 5 minutes;

[0086] The temperature of the second scanning treatment was 28° C. and the time was 3 min.

[0087] Example 2

[0088] This example adopts the same process as Example 1, except that: Solution 1 in step (3) is replaced by an equal volume of Solution 4 (i.e., the mixed collector I-2 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.2), and the rest is the same as Example 1.

[0089] Example 3

[0090] This example adopts the same process as Example 1, except that: Solution 2 in step (4) is replaced by an equal volume of Solution 5 (i.e., the mixed collector II-2 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.7), and the rest is the same as Example 1.

[0091] Example 4

[0092] This embodiment adopts a similar process to that of Embodiment 1, except that: this embodiment does not perform step (5) and step (6), and the rest is the same as that of Embodiment 1.

[0093] Example 5

[0094] This example adopts the same process as Example 1, except that the volume of solution 1 in step (3) is adjusted to 90 mL (i.e., the amount of mixed collector I-1 is 900 g per ton of coal gangue powder), and the rest is the same as Example 1.

[0095] Example 6

[0096] This example is carried out in the same process as Example 1, except that the total volume of solution 3 in step (6) is adjusted to 11 mL. Specifically,

[0097] (6) 6 mL of the solution 3 prepared in Preparation Example 2 was contacted with the second slurry for a second roughing treatment to obtain a flotation foam III containing the third kaolin concentrate-1 and a tailings slurry III containing quartz and feldspar, 3 mL of the solution 3 prepared in Preparation Example 2 was contacted with the tailings slurry III for a first second scavenging treatment to obtain a flotation foam IV containing the third kaolin concentrate-2 and a tailings slurry IV containing quartz and feldspar, 2 mL of the solution 3 prepared in Preparation Example 2 was contacted with the tailings slurry IV for a second second scavenging treatment to obtain a flotation foam V containing the third kaolin concentrate-3 and a tailings slurry V containing quartz and feldspar (i.e., the total amount of octadecylamine used was 110 g per ton of coal gangue powder), and the flotation foam III, the flotation foam IV, and the flotation foam V were subjected to a third filtration and drying treatment to obtain a third kaolin concentrate, and the tailings slurry V was subjected to a third filtration and drying treatment to obtain a feldspar mixed concentrate;

[0098] The third filtering and drying treatment includes: washing and filtering the flotation foam and the tailings pulp V with water, respectively, and drying the filtered products at 105° C. for 60 min; the rest is the same as in Example 1.

[0099] Example 7

[0100] This example adopts the same process as Example 1, except that the volume of solution 2 in step (4) is adjusted to 100 mL (i.e., the weight ratio of mixed collector I-1 to mixed collector II-1 is 1:2), and the rest is the same as Example 1.

[0101] Comparative Example 1

[0102] This comparative example adopts the same process as Example 1, except that: Solution 1 in step (3) is replaced by an equal volume of Solution 2 (i.e., the mixed collector II-1 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.1), and the rest is the same as Example 1.

[0103] Comparative Example 2

[0104] This comparative example adopts the same process as Example 1, except that: Solution 2 in step (4) is replaced by an equal volume of Solution 6 (i.e., the mixed collector II-3 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:2), and the rest is the same as Example 1.

[0105] Comparative Example 3

[0106] This comparative example is carried out using a process similar to that of Example 1, except that step (2) is not performed. Specifically,

[0107] (1) contacting 1 kg of the coal gangue powder with a particle size of less than 75 μm obtained in Preparation Example 1 with water to obtain a coal gangue slurry with a concentration of 30 wt %;

[0108] (2) taking 50 mL of the solution 1 prepared in Preparation Example 2 and contacting it with a coal gangue slurry to perform a first roughing treatment, thereby obtaining a flotation foam I containing a first kaolin concentrate and a tailings slurry I (i.e., the amount of the mixed collector I-1 is 500 g per ton of coal gangue powder, wherein the mixed collector I-1 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.5), and performing a first filtration and drying treatment on the flotation foam I containing the first kaolin concentrate to obtain a first kaolin concentrate;

[0109] The first filtering and drying treatment comprises: washing and filtering the flotation foam I with water, and drying the filtered product at 105° C. for 60 minutes;

[0110] The first roughing treatment was performed at a temperature of 28°C and for 5 minutes;

[0111] (3) taking 30 mL of the solution 2 prepared in Preparation Example 2 and contacting it with the tailings slurry I to perform a first scavenging treatment to obtain a flotation foam II containing a second kaolin concentrate and a tailings slurry II (i.e., the amount of the mixed collector II-1 is 300 g per ton of coal gangue powder, and the weight ratio of the mixed collector I-1 to the mixed collector II-1 is 1:0.6, wherein the mixed collector II-1 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.1), and performing a second filtration and drying treatment on the flotation foam II containing the second kaolin concentrate to obtain a second kaolin concentrate;

[0112] The second filtering and drying treatment comprises: washing and filtering the flotation foam II with water, and drying the filtered product at 105° C. for 60 minutes;

[0113] The temperature of the first sweep treatment was 28°C and the time was 3 minutes;

[0114] (4) contacting and mixing the tailings slurry II with hydrochloric acid to obtain a second slurry with a pH of 2;

[0115] (5) 4 mL of the solution 3 prepared in Preparation Example 2 was contacted with the second slurry for a second roughing treatment to obtain a flotation foam III containing the third kaolin concentrate-1 and a tailings slurry III containing quartz and feldspar, 2 mL of the solution 3 prepared in Preparation Example 2 was contacted with the tailings slurry III for a first second scavenging treatment to obtain a flotation foam IV containing the third kaolin concentrate-2 and a tailings slurry IV containing quartz and feldspar, 2 mL of the solution 3 prepared in Preparation Example 2 was contacted with the tailings slurry IV for a second second scavenging treatment to obtain a flotation foam V containing the third kaolin concentrate-3 and a tailings slurry V containing quartz and feldspar (i.e., the total amount of octadecylamine used was 80 g per ton of coal gangue powder), and the flotation foam III, the flotation foam IV, and the flotation foam V were subjected to a third filtration and drying treatment to obtain a third kaolin concentrate, and the tailings slurry V was subjected to a third filtration and drying treatment to obtain a feldspar mixed concentrate;

[0116] The third filtering and drying treatment comprises: washing and filtering the flotation foam and the tailings pulp V with water, respectively, and drying the filtered products at 105° C. for 60 minutes;

[0117] The second roughing treatment was performed at a temperature of 28°C and for 5 minutes;

[0118] The temperature of the second scanning treatment was 28° C. and the time was 3 min.

[0119] Comparative Example 4

[0120] The difference between this comparative example and Example 1 is that the gangue slurry is first subjected to flotation operation with an amine cationic collector, and then subjected to flotation operation with mixed collectors I-1 and II-1. Specifically:

[0121] (1) contacting 1 kg of the coal gangue powder with a particle size of less than 75 μm obtained in Preparation Example 1 with water to obtain a coal gangue slurry with a concentration of 30 wt %;

[0122] (2) contacting and mixing the coal gangue slurry with hydrochloric acid to obtain a slurry I with a pH of 2;

[0123] (3) 4 mL of the solution 3 prepared in Preparation Example 2 was contacted with the slurry 1 for a first roughing treatment to obtain a flotation foam-1 containing the first kaolin concentrate-1 and a tailings slurry-1 containing quartz and feldspar, 2 mL of the solution 3 prepared in Preparation Example 2 was contacted with the tailings slurry-1 for a first first scavenging treatment to obtain a flotation foam-2 containing the first kaolin concentrate-2 and a tailings slurry-2 containing quartz and feldspar, 2 mL of the solution 3 prepared in Preparation Example 2 was contacted with the tailings slurry-2 for a second first scavenging treatment to obtain a flotation foam-3 containing the first kaolin concentrate-3 and a tailings slurry-3 containing quartz and feldspar (i.e., the total amount of octadecylamine used per ton of coal gangue powder is 80 g), and the flotation foam-1, the flotation foam-2, and the flotation foam-3 were subjected to a first filtration and drying treatment to obtain a first kaolin concentrate;

[0124] The first filtering and drying treatment includes: washing and filtering the flotation foam with water, and drying the filtered product at 105° C. for 60 minutes;

[0125] The first roughing treatment was performed at a temperature of 28°C and for 5 minutes;

[0126] The temperature of the first sweep treatment was 28°C and the time was 3 minutes;

[0127] (4) contacting and mixing the tailings slurry-3 with a 5% NaOH solution to obtain a slurry II having a pH of 5;

[0128] (5) taking 50 mL of the solution 1 prepared in Preparation Example 2 and contacting it with the slurry II for a second roughing treatment to obtain a flotation foam-4 containing a second kaolin concentrate and a tailings slurry-4 (i.e., the amount of the mixed collector I-1 is 500 g per 1 ton of coal gangue powder, wherein the mixed collector I-1 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.5), and performing a second filtration and drying treatment on the flotation foam-4 containing the second kaolin concentrate to obtain a second kaolin concentrate;

[0129] The second filtering and drying treatment includes: washing and filtering the flotation foam-4 with water, and drying the filtered product at 105° C. for 60 minutes;

[0130] The second roughing treatment was performed at a temperature of 28°C and for 5 minutes;

[0131] (6) 30 mL of the solution 2 prepared in Preparation Example 2 is taken and contacted with the tailings slurry-4 for a second scavenging treatment to obtain a flotation foam-5 and a tailings slurry-5 containing a third kaolin concentrate (i.e., with respect to each ton of coal gangue powder, the amount of the mixed collector II is 300 g, and the weight ratio of the mixed collector I-1 to the mixed collector II-1 is 1:0.6, wherein the mixed collector II-1 is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.1), and the flotation foam-5 containing the third kaolin concentrate and the tailings slurry-5 containing quartz and feldspar are subjected to a third filtration and drying treatment to obtain a third kaolin concentrate and a feldspar mixed concentrate;

[0132] The third filtering and drying treatment includes: washing and filtering the flotation foam-5 and the tailings slurry-5 with water, and drying the filtered product at 105° C. for 60 minutes;

[0133] The temperature of the second scanning treatment was 28° C. and the time was 3 min.

[0134] Tables 1 to 3 are the data of purified kaolin concentrate and feldspar mixed concentrate of Examples and Comparative Examples, and the specific contents are as follows:

[0135] Table 1

[0136]

[0137] Table 2

[0138]

[0139] Table 3

[0140] serial number Comparative Example 4 Purity of concentrate / % First Kaolin Concentrate 62 Second kaolin concentrate 30 The third kaolin concentrate 16 Feldspar mixed concentrate 1.2 Total recovery rate of kaolin concentrate / % 61

[0141] Application preparation example:

[0142] The first kaolin concentrate prepared in Example 1 is subjected to roasting treatment to obtain calcined kaolin;

[0143] The calcination conditions include: temperature of 750°C and time of 3 hours.

[0144] Application examples:

[0145] The calcined kaolin prepared in the preparation example, the gangue sand prepared in the preparation example 1, limestone sand, cement, limestone powder (filler), cellulose ether, starch ether and water are stirred to obtain masonry mortar;

[0146] The stirring temperature was 27°C, the stirring time was 3 min, and the amounts of each component were as shown in Table 4;

[0147] Table 4

[0148] Components Weight / g gangue sand 100 Limestone sand 243 cement 51 Limestone powder 35 Calcined Kaolin 6 Cellulose ether 0.1 Starch ether 0.02 water 65

[0149] Note: 1g is equal to 1 part by weight

[0150] Test example:

[0151] The masonry mortar prepared in the application example was tested according to the standard of GB / T 25181-2019, and the test results are shown in Table 5.

[0152] Table 5

[0153] performance index GB / T25181-2019 requirements Consistency mm 73 75±5 Water retention rate / % 91.7 ≥88.0 2h consistency loss / % 22.6 ≤30.0 Coagulation time / h 5.25 3-12 28d compressive strength MPa 10.5 ≥10.0

[0154] It can be seen from the above contents that the method for purifying kaolin concentrate product of the present invention can obtain a kaolin concentrate with high purity and high recovery rate.

[0155] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for purifying kaolin concentrate product, characterized in that: The method includes: (1) contacting a coal gangue slurry with an acid solution I to adjust the pH value of the coal gangue slurry to obtain a first slurry with a pH value of 5-6; the coal gangue slurry is formed by contacting coal gangue with water; (2) contacting the first slurry with a mixed collector I to perform a first roughing treatment to obtain a first kaolin concentrate and tailings slurry I; the mixed collector I is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.2-0.8; (3) contacting the tailings slurry I with a mixed collector II to perform a first scavenging treatment to obtain a second kaolin concentrate and tailings slurry II; the mixed collector II is saponified oleic acid and sodium petroleum sulfonate in a weight ratio of 1:0.1-0.8; The first kaolin concentrate and / or the second kaolin concentrate can be used as the kaolin concentrate product.

2. The method according to claim 1, characterized in that The method further comprises step (4): contacting the tailings slurry II with an acid solution II to adjust the pH value of the tailings slurry II to obtain a second slurry with a pH value of 2-3; and contacting the second slurry with an amine cationic collector to sequentially perform a second roughing treatment and at least one second scavenging treatment to obtain a mixed concentrate and a third kaolin concentrate; the mixed concentrate contains quartz and feldspar, and at least one of the first kaolin concentrate, the second kaolin concentrate and the third kaolin concentrate can be used as the kaolin concentrate product; Preferably, the total amount of the amine cationic collector is 10-100 g per ton of the coal gangue; Preferably, the amine cationic collector is dodecylamine and / or octadecylamine.

3. The method according to claim 1 or 2, characterized in that: The amount of the mixed collector I is 300-800 g for every 1 ton of the coal gangue; And / or, the weight ratio of the mixed collector I to the mixed collector II is 1:0.1-1.

5.

4. The method according to claim 1 or 2, characterized in that: The conditions of the first roughing treatment include: temperature of 10-40° C., time of 3-5 min; the conditions of the first sweeping treatment include: temperature of 10-40° C., time of 1-3 min.

5. The method according to claim 2, characterized in that: The conditions of the second roughing treatment include: temperature of 10-40°C and time of 3-5 minutes; the conditions of the second sweeping treatment include: temperature of 10-40°C and time of 1-3 minutes.

6. The method according to claim 3, characterized in that The coal gangue contains 40-58wt% of kaolin, 30-40wt% of quartz, 10-20wt% of feldspar, 0.5-1.5wt% of siderite, 0.1-1wt% of calcite, 0.1-0.6wt% of pyrite and 0.1-0.5wt% of dolomite.

7. The method according to claim 1 or 2, characterized in that: The gangue slurry is an aqueous solution with a concentration of 25-35wt%; And / or, in step (1), the coal gangue used to form the coal gangue slurry is coal gangue powder, and the particle size of the coal gangue powder is less than 75 μm.

8. The method according to claim 1 or 2, characterized in that: The method further comprises: subjecting the first kaolin concentrate and / or the second kaolin concentrate to magnetic separation to obtain a product that can be used as the kaolin concentrate; Preferably, the magnetic field strength of the magnetic separation is 1.0-1.3T.

9. Use of kaolin concentrate purified by the method described in claims 1 to 8 in building mortar.

10. A building mortar, characterized in that: The building mortar contains calcined kaolin, limestone sand, coal gangue sand, cement, filler, cellulose ether, starch ether and water; the calcined kaolin is a product obtained by roasting kaolin concentrate; The kaolin concentrate is the kaolin concentrate product obtained by the method described in claims 1-8; Preferably, for every 100 parts by weight of coal gangue sand, the amount of the calcined kaolin is 4-12 parts by weight, the amount of the limestone sand is 240-245 parts by weight, the amount of the cement is 45-55 parts by weight, the amount of the filler is 30-38 parts by weight, the amount of the cellulose ether is 0.06-0.12 parts by weight, the amount of the starch ether is 0.01-0.04 parts by weight, and the amount of water is 65-80 parts by weight; Preferably, the calcination treatment is carried out at a temperature of 600-900°C and for a time of 1-5 hours.

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