Fluorite tailings calcium silicate board and preparation method thereof

Abstract

The application relates to the technical field of plate materials, and discloses a fluorite tailing slag calcium silicate plate material and a preparation method thereof. The fluorite tailing slag calcium silicate plate material comprises quartz sand, cement, fluorite tailing slag, paper pulp and glass fibers. The components are added into water and stirred to form a mixed slurry, and then the mixed slurry is sequentially subjected to a taking forming process, a pre-curing treatment, a steam pressure curing and drying, so that the calcium silicate plate material is obtained. The fluorite tailing slag is doped in the calcium silicate plate material in a large amount, so that the fluorite tailing slag is utilized as waste, the production cost of the plate material is reduced, and compared with a traditional calcium silicate plate material, the heat preservation and heat insulation performance and the mechanical strength of the calcium silicate plate material are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of plate material, in particular to a fluorite tailings calcium silicate plate material and a preparation method thereof. BACKGROUND

[0002] The main chemical component of fluorite is calcium fluoride, which is a transparent rock with white, red, blue, green and purple color. Most fluorite in nature is mixed with silicon oxide, calcium carbonate, iron oxide and aluminum oxide. The melting point of fluorite is 1230℃, and fluorite has strong fluxing effect and is a fluxing agent raw material in glaze. The fluorite tailings formed after fluorite mining and processing have the following chemical components: 42.76% of silicon dioxide, 7.58% of aluminum oxide, 1.02% of iron oxide, 38.97% of calcium oxide, 2.82% of magnesium oxide, 1.10% of potassium oxide, 0.44% of sodium oxide, 51.69% of diaphosphorus pentoxide, 0.2% of sulfur trioxide, 0.12% of titanium oxide, 2.00% of fluorine and 1.36% of loss on ignition. From the chemical composition, the main component of fluorite tailings is calcium silicate. For a long time, the comprehensive utilization of fluorite tailings has been a worldwide problem. Although a large number of researches on the comprehensive utilization of fluorite tailings have been carried out at home and abroad, most of them have not been put into industrial implementation due to various technical and economic reasons. Calcium silicate plate material can be used as thermal insulation material or decorative material. The thermal insulation calcium silicate plate material is mainly used for external wall hanging plate, external wall veneer and the like. The decorative calcium silicate plate material is mainly used for suspended ceiling, ceiling, house partition wall, indoor floor and the like. With the continuous expansion of the market of thermal insulation and decorative finished plate, the demand for calcium silicate plate material also increases.

[0003] Chinese patent publication CN104926236 discloses a low-density fiber-reinforced calcium silicate fireproof plate and a preparation method thereof, which comprises the following steps: step 1, mixing plant fibers, cement and quartzite to prepare slurry, wherein the molar ratio of calcium to silicon is 0.80-0.82, and the mass of plant fibers accounts for 8%-12% of the total weight of raw materials; step 2, forming a plate blank to prepare a material blank; step 3, pre-reaction: placing the material blank in a reaction kettle, and under the pressure of 1.2±0.1 Mpa in the reaction kettle, the self-steam enters the reaction kettle, and the temperature is raised to 250℃ at a rate of 30℃ / h, and then the temperature is kept constant for not less than 24 h; step 4, autoclave curing; step 5, demolding, drying and sanding to obtain the low-density fiber-reinforced calcium silicate fireproof plate. Chinese patent publication CN115959867 discloses a preparation method of modified conch antibacterial calcium silicate board. The method comprises the following steps: immersing biomass waste conch in a Cu(NO3)2·3H2O solution, filtering the obtained solid, and calcining the solid to obtain a CuO / CaO powder; adding water to hydrate the CuO / CaO powder to obtain a CuO / Ca(OH)2 powder; mixing the CuO / Ca(OH)2 powder with diatomite, adding fibers and ordinary Portland cement to obtain a mixed powder, and then adding water to stir to obtain a slurry; and performing mold pressing and autoclave curing to obtain the modified conch antibacterial calcium silicate board. The calcium silicate board prepared by the above patent documents has limited strength, and the mechanical strength of the calcium silicate board needs to be further improved. SUMMARY

[0004] The present application is to overcome the above problems in the prior art, and provides a fluorite tailings calcium silicate board and a preparation method thereof. The application realizes waste utilization of fluorite tailings, reduces the production cost of the board, and improves the thermal insulation performance and mechanical strength of the calcium silicate board compared with traditional calcium silicate board by doping a large amount of fluorite tailings in the calcium silicate board.

[0005] In order to achieve the above application purposes, the present application adopts the following technical solutions:

[0006] A fluorite tailings calcium silicate board, comprising the following components by dry weight in parts by weight:

[0007] Quartz sand 35-45 parts

[0008] Cement 25-30 parts

[0009] Fluorite tailings 20-30 parts

[0010] Paper pulp 4-8 parts.

[0011] The main components of the calcium silicate plate in the prior art are cement, quartz sand and paper pulp, etc., the fluorite tailings are doped in the calcium silicate plate in a large amount in the application, not only the waste utilization of the fluorite tailings is realized, the production cost of the plate is reduced, compared with the traditional calcium silicate plate, the heat insulation performance and the mechanical strength of the calcium silicate plate are also improved.

[0012] As preferred, the calcium silicate plate further comprises glass fibers.

[0013] The calcium silicate plate in the prior art usually realizes the strength enhancement of the calcium silicate plate by adding single paper pulp, but the strength of the calcium silicate plate is limited by adding single cotton pulp. The cotton pulp fibers and glass fibers are mixed and added to the calcium silicate plate in the application, and the synergistic effect of the two further improves the mechanical strength of the calcium silicate plate.

[0014] As preferred, the mass ratio of the glass fibers to the paper pulp is 1:1-5.

[0015] As preferred, the glass fibers are subjected to modification treatment, and the modification method comprises the following steps:

[0016] 1) γ-glycidyl ether propyltrimethoxysilane is added to a mixed solution of ethanol and water, heated and stirred to dissolve, to obtain a silane coupling agent solution, the glass fibers are added to the silane coupling agent solution for reaction, and after separation and drying, the coupling agent modified glass fibers are obtained.

[0017] 2) sodium alginate is added to water and stirred to dissolve, a sodium hydroxide catalyst is added, then the coupling agent modified glass fibers are added for reaction, and after separation and drying, the product is obtained.

[0018] Through experiments, it is found that the ordinary glass fibers are difficult to be uniformly dispersed in the calcium silicate plate components, and the glass fibers and the paper pulp cannot form an interwoven three-dimensional network structure. The glass fibers are further modified in the application, the surface of the glass fibers is grafted with epoxy groups through a silicic acid coupling agent, then the epoxy groups react with the hydroxyl groups on the sodium alginate to graft the sodium alginate on the surface of the glass fibers, so that the COO - Under the action of electrostatic repulsion, the glass fibers can be fully dispersed in the components, and the hydroxyl groups on the sodium alginate molecules that do not participate in the reaction form hydrogen bond force with the hydroxyl groups on the surface of the paper pulp fibers, and the two form an interwoven three-dimensional network, thereby greatly further improving the mechanical strength of the calcium silicate plate.

[0019] As preferred, the heating temperature in step 1) is 40-60℃.

[0020] Preferably, the mass ratio of the glass fiber to the silane coupling agent in step 1) is 1:0.2-0.6.

[0021] Preferably, the reaction time in step 1) is 3-5h.

[0022] Preferably, the mass ratio of the coupling agent modified glass fiber to the sodium alginate in step 2) is less than 1:0.5.

[0023] When the mass ratio of the coupling agent modified glass fiber to the sodium alginate is greater than 1:0.5, the excess epoxy groups on the surface of the coupling agent modified glass fiber will fully react with the hydroxyl groups on the surface of the glass fiber, resulting in the lack of hydroxyl groups on the surface of the final obtained glass fiber, which cannot form hydrogen bonding force with the hydroxyl groups on the pulp fiber, thus affecting the further improvement of the strength of the calcium silicate board. Therefore, the mass ratio of the coupling agent modified glass fiber to the sodium alginate is controlled to be less than 1:0.5.

[0024] Preferably, the reaction time in step 3) is 30-60min.

[0025] A preparation method of a fluorite tailings calcium silicate board, comprising the following steps:

[0026] 1) crushing the fluorite tailings into a granular shape, then mixing with quartz sand and cement, and adding water to stir into a slurry;

[0027] 2) adding pulp or adding pulp and glass fiber or adding pulp and modified glass fiber to the slurry, and continuing to stir uniformly to obtain a mixed slurry;

[0028] 3) sequentially passing the mixed slurry through a papermaking forming, a pre-culture treatment, a steam pressure curing and drying to obtain a calcium silicate board.

[0029] The present application has the following beneficial effects:

[0030] 1) The present application realizes the waste utilization of fluorite tailings, reduces the production cost of the board, and improves the thermal insulation performance and mechanical strength of the calcium silicate board compared with the traditional calcium silicate board by doping a large amount of fluorite tailings in the calcium silicate board.

[0031] 2) The present application further improves the mechanical strength of the calcium silicate board by adding cotton pulp fiber and glass fiber to the calcium silicate board.

[0032] 3) The modified glass fiber can be fully dispersed in the components, and the modified glass fiber and the pulp fiber form an interwoven three-dimensional network, thereby further improving the mechanical strength of the calcium silicate board. DETAILED DESCRIPTION

[0033] The raw materials and equipment used in the specific embodiments of the present application, unless specified otherwise, can be purchased from the market or commonly used in the art, and the methods in the embodiments are conventional methods in the art unless specified otherwise. Embodiment

[0034] A fluorite tailings slag calcium silicate board comprises the following components by weight parts of dry weight:

[0035] Quartz sand 44 parts

[0036] Cement 28 parts

[0037] Fluorite tailings slag 29 parts

[0038] Paper pulp 7 parts.

[0039] A preparation method of a fluorite tailings slag calcium silicate board comprises the following steps:

[0040] 1) The fluorite tailings slag is crushed into granular form, then mixed with quartz sand and cement, and water is added to stir into a slurry;

[0041] 2) Paper pulp is added to the slurry and stirred evenly to obtain a mixed slurry;

[0042] 3) The mixed slurry is sequentially subjected to extraction molding, pre-curing treatment, steam pressure curing and drying, the pre-curing treatment temperature is 60°C, the time is 8h, and the pressure is 0.12MPa; the steam pressure curing temperature is 150°C, the time is 18h, and the pressure is 1.0MPa, to obtain a calcium silicate board.

[0043] Comparative Example 1

[0044] The difference between Comparative Example 1 and Embodiment 1 is that the fluorite tailings slag is replaced by quartz sand. Embodiment

[0045] A fluorite tailings slag calcium silicate board comprises the following components by weight parts of dry weight:

[0046] Quartz sand 34 parts

[0047] Cement 26 parts

[0048] Fluorite tailings slag 25 parts

[0049] Paper pulp 5 parts

[0050] Glass fiber 3 parts.

[0051] A preparation method of a fluorite tailings slag calcium silicate board comprises the following steps:

[0052] 1) The fluorite tailings slag is crushed into granular form, then mixed with quartz sand and cement, and water is added to stir into a slurry;

[0053] 2) adding paper pulp and glass fiber into the slurry, and continuously stirring to obtain a mixed slurry;

[0054] 3) sequentially passing the mixed slurry through a papermaking forming, a pre-curing treatment, a steam pressure curing and maintenance, and a drying, the pre-curing treatment has a temperature of 60°C and a time of 9h, and a pressure of 0.13MPa; the steam pressure curing has a temperature of 155°C, a time of 20h, and a pressure of 1.2MPa, to obtain a calcium silicate board. Embodiment

[0055] A fluorite tailings calcium silicate board includes the following components by weight parts:

[0056] quartz sand 45 parts

[0057] cement 30 parts

[0058] fluorite tailings 30 parts

[0059] paper pulp 8 parts

[0060] modified glass fiber 8 parts.

[0061] A preparation method of the modified glass fiber includes the following steps:

[0062] 1) adding γ-glycidoxypropyltrimethoxysilane into a mixed solution of ethanol and water mixed according to a ratio of 5:1, the γ-glycidoxypropyltrimethoxysilane accounts for 5% of the mass of the mixed solution, heating to 60°C, stirring and dissolving to obtain a silane coupling agent solution, adding glass fiber into the silane coupling agent solution for reaction for 5h, the mass ratio of the glass fiber to the silane coupling agent being 1:0.6, and then separating and drying to obtain the coupling agent modified glass fiber;

[0063] 2) adding sodium alginate into water to stir and dissolve to prepare a sodium alginate solution with a concentration of 0.5wt%, adding a sodium hydroxide catalyst with a mass concentration percentage of 0.1%, and then adding the coupling agent modified glass fiber for reaction for 60min, the mass ratio of the coupling agent modified glass fiber to the sodium alginate being 1:0.5, and then separating and drying to obtain the modified glass fiber.

[0064] A preparation method of a fluorite tailings calcium silicate board includes the following steps:

[0065] 1) crushing the fluorite tailings into a granular form, and then mixing with quartz sand and cement, and adding water to stir into a slurry;

[0066] 2) adding paper pulp and the modified glass fiber into the slurry, and continuously stirring to obtain a mixed slurry;

[0067] 3) The mixed slurry is sequentially subjected to suction forming, pre-curing treatment, steam pressure curing and drying, the pre-curing treatment temperature is 60℃, the time is 8h, and the pressure is 0.10MPa; the steam pressure curing temperature is 160℃, the time is 15h, and the pressure is 1.0MPa, to obtain the calcium silicate board.

[0068] Comparative Example 2

[0069] The difference between Comparative Example 2 and Example 3 is that the mass ratio of the coupling agent modified glass fiber to sodium alginate in the preparation process of the modified glass fiber is 1:0.4. Example

[0070] A kind of fluorite tailings calcium silicate board includes the following components by weight parts of dry weight:

[0071] Quartz sand 35 parts

[0072] Cement 25 parts

[0073] Fluorite tailings 20 parts

[0074] Paper pulp 4 parts

[0075] Modified glass fiber 0.8 parts.

[0076] The preparation method of the modified glass fiber includes the following steps:

[0077] 1) γ-glycidoxypropyltrimethoxysilane is added to a mixed solution of ethanol and water mixed according to a mass ratio of 5:1, the mass fraction of γ-glycidoxypropyltrimethoxysilane in the mixed solution is 5%, heated to 40℃, stirred and dissolved to obtain a silane coupling agent solution, glass fiber is added to the silane coupling agent solution for reaction for 3h, the mass ratio of glass fiber to silane coupling agent is 1:0.2, and after separation and drying, a coupling agent modified glass fiber is obtained.

[0078] 2) Sodium alginate is added to water and stirred and dissolved to prepare a sodium alginate solution with a concentration of 0.5wt%, then a sodium hydroxide catalyst with a mass concentration percentage of 0.1% is added, and then a coupling agent modified glass fiber is added for reaction for 30min, the mass ratio of the coupling agent modified glass fiber to sodium alginate is 1:0.6, and after separation and drying, it is obtained.

[0079] A preparation method of a fluorite tailings calcium silicate board includes the following steps:

[0080] 1) The fluorite tailings are crushed into granular form, then mixed with quartz sand and cement, and stirred into a slurry with water;

[0081] 2) Paper pulp and modified glass fiber are added to the slurry, and continue to stir uniformly to obtain a mixed slurry;

[0082] 3) The mixed slurry is sequentially subjected to a taking molding, a pre-curing treatment, a steam pressure curing and drying, the pre-curing treatment temperature is 70℃, the time is 12h, the pressure is 0.10MPa; the steam pressure curing temperature is 180℃, the time is 13h, the pressure is 1.0MPa, to obtain the calcium silicate board.

[0083] Performance test

[0084] The strength of the calcium silicate board is tested according to CB / T8040, and the thermal conductivity is tested according to GB / T10294.

[0085] The above is only the preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with the preferred embodiment, it is not intended to limit the present application. Any skilled person in the art can make some changes or modifications to the above disclosed technical content without departing from the technical solution of the present application, and any simple modification, equivalent change and modification of the above embodiment according to the technical essence of the present application are still within the scope of the technical solution of the present application.

Claims

1. A fluorite tailings calcium silicate board material, characterized in that, The calcium silicate board comprises the following components by weight parts of dry weight: Quartz sand 35-45 parts Cement 25-30 parts Fluorite tailings 20-30 parts Paper pulp 4-8 parts The calcium silicate board further comprises glass fibers, and the glass fibers are modified by the following steps: Step 1) γ-glycidyl ether propyltrimethoxysilane is added to a mixed solution of ethanol and water, and heated and stirred to dissolve, to obtain a silane coupling agent solution; the glass fibers are added to the silane coupling agent solution for reaction, and the mass ratio of the glass fibers to the silane coupling agent is 1:0.2-0.6; after separation and drying, the coupling agent modified glass fibers are obtained; Step 2) sodium alginate is added to water and stirred to dissolve; sodium hydroxide catalyst is added, followed by the coupling agent modified glass fibers for reaction; after separation and drying, the modified glass fibers are obtained; The mass ratio of the glass fibers to the paper pulp is 1:1-5, and the mass ratio of the coupling agent modified glass fibers in Step 2) to the sodium alginate is less than 1:0.

5.

2. The fluorite tailings calcium silicate board according to claim 1, characterized in that, The heating temperature in Step 1) is 40-60℃.

3. The fluorite tailings calcium silicate board according to claim 1, characterized in that, The reaction time in Step 1) is 3-5h.

4. The fluorite tailings calcium silicate board according to claim 1, characterized in that, The reaction time in Step 2) is 30-60min.

5. A method of manufacturing a calcium silicate board from fluorite tailings as claimed in any one of claims 1 to 4, characterised in that, The method comprises the following steps: The fluorite tailings are crushed into granular form, and then mixed with quartz sand and cement, and water is added for stirring to form a slurry; The paper pulp and the modified glass fibers are added to the slurry, and stirring is continued until uniform, to obtain a mixed slurry; The mixed slurry is sequentially subjected to sheet forming, pre-curing treatment, autoclave curing and drying, to obtain the calcium silicate board.