阅读说明：本技术 一种硅酸镁粉粒体及其制备方法和应用 (Magnesium silicate powder and preparation method and application thereof ) 是由 孙红娟 彭同江 罗利明 唐颂 于 2021-09-22 设计创作，主要内容包括：本发明提供了一种硅酸镁粉粒体及其制备方法和应用,所述制备方法包括：将含有蛇纹石矿物的原料进行干燥、破碎和粉磨处理,获得含有蛇纹石矿物的粉粒体；将所述含有蛇纹石矿物的粉粒体进行煅烧,获得主晶相为橄榄石的硅酸镁粉粒体,其中,煅烧温度为850℃～1200℃,时间为10min～2h。所述硅酸镁粉粒体采用如上所述的制备方法制备获得,可作为建筑集料、聚合物填料、冶金助溶剂、磨料、喷砂料或耐火材料原料。本发明具有生产工艺简单、节能减排、产品附加值高、生态环境效益高等优势,对发展新材料产业与社会经济具有重要意义。(The invention provides a magnesium silicate powder and a preparation method and application thereof, wherein the preparation method comprises the following steps: drying, crushing and grinding the raw material containing the serpentine mineral to obtain powder containing the serpentine mineral; and calcining the powder containing the serpentine mineral to obtain the magnesium silicate powder with the main crystal phase of olivine, wherein the calcining temperature is 850-1200 ℃, and the calcining time is 10 min-2 h. The magnesium silicate powder is prepared by the preparation method, and can be used as building aggregate, polymer filler, metallurgy cosolvent, abrasive, sand blasting material or refractory material. The invention has the advantages of simple production process, energy conservation, emission reduction, high added value of products, high ecological environmental benefit and the like, and has important significance for developing new material industry and social economy.)

1. A preparation method of magnesium silicate powder is characterized by comprising the following steps:

drying, crushing and grinding the raw material containing the serpentine mineral to obtain powder containing the serpentine mineral;

and calcining the powder containing the serpentine mineral to obtain the magnesium silicate powder with the main crystal phase of olivine, wherein the calcining temperature is 850-1200 ℃, and the calcining time is 10 min-2 h.

2. The method for producing a magnesium silicate powder according to claim 1, wherein the raw material containing a serpentine mineral is at least one selected from the group consisting of serpentine, serpentine beneficiation tailing, chrysotile beneficiation tailing, and ultrabedrock type mineral beneficiation tailing.

3. The method for producing magnesium silicate powder/granules according to claim 1, wherein the drying temperature is 80 ℃ to 105 ℃; the content of adsorbed water in the serpentine mineral-containing powder is less than 4%.

4. The method for producing magnesium silicate powder according to claim 3, wherein the drying temperature is 90 ℃ to 105 ℃; the content of the absorbed water in the serpentine mineral-containing powder is 1-2%.

5. The method of producing magnesium powder according to claim 1, wherein the particle size of the powder containing a serpentine mineral is 0.03 to 80 mm.

6. The method of preparing magnesium powder according to claim 1, wherein the powder containing serpentine mineral is calcined in a vertical kiln, a rotary kiln or a pre-decomposition kiln.

7. The method of claim 1, wherein the serpentine mineral-containing powder comprises 25-40% MgO and 35-40% SiO, by mass₂、2％～10％CaO、5％～15％Fe₂O₃And 1 to 5% of Al₂O₃。

8. A magnesium silicate powder, characterized in that it is produced by the method for producing a magnesium silicate powder according to any one of claims 1 to 7.

9. The magnesium silicate powder according to claim 8, wherein the magnesium silicate powder has a mohs hardness of 6.5 to 7.5, a bulk compressive strength of 50 to 180MPa, and a refractoriness of 1500 to 2100 ℃.

10. Use of the magnesium silicate powder or granules according to claim 8 as a raw material for building aggregates, polymer fillers, metallurgical aids, abrasives, sandblasting materials or refractories.

Technical Field

The invention relates to the technical field of resource utilization of a serpentine-containing mineral raw material, in particular to a method for preparing a magnesium silicate powder particle body by using the serpentine-containing mineral raw material, the magnesium silicate powder particle body and application of the magnesium silicate powder particle body.

Background

Serpentine is a layered silicate mineral with the molecular formula Mg₃Si₂O₅(OH)₄Or 2SiO₂·3MgO·2H₂And O. Serpentine is usually in the form of dense blocks, flakes or fibers, and can be classified into chrysotile, lizardite (scale serpentine) and antigorite according to their structure types, and they are usually dark green, black green, yellowish green, etc. in most cases. The serpentine mineral has poor thermal sensitivity, low water absorption, heat insulation, sound insulation, wear resistance, heat resistance, corrosion resistance and other properties, has better process characteristics and associated beneficial components, can be used as raw materials of various industrial products and various materials, and has very wide application prospect.

China has rich serpentine mineral resources and good quality, and most serpentine minerals are accompanied with various other metals. But the comprehensive utilization level of serpentine is not high, and particularly the valuable components are enriched and the utilization efficiency of the whole components is low. In addition, the serpentine is symbiotic and associated with various minerals, and nearly ten million tons of raw materials containing serpentine minerals are discharged every year in China. At present, most of raw materials containing serpentine minerals cannot be recycled, mainly are stockpiled as main materials, are used as dangerous solid waste asbestos tailings, tailings and stripped waste rocks, are piled up like a mountain on one hand, occupy a large amount of land resources, have potential harm to the surrounding environment, and increase the transportation investment and the cost of stockpiling management on the other hand.

Therefore, the comprehensive recovery of the raw material containing the serpentine mineral can improve the natural ecological environment and realize the secondary recovery of resources, thereby increasing new benefits and development for mine enterprises, and being the main direction for development and utilization in the future.

In recent years, the development and utilization range of serpentine is expanded year by year, but various magnesium-silicon series chemical industrial products are produced by taking serpentine as a raw material according to different industrial requirements. Wherein, the magnesium series products comprise magnesium hydroxide, basic magnesium carbonate, magnesium oxide, magnesium carbonate, metal magnesium and the like, and also products such as magnesium compound whisker materials, nanometer materials and the like with high added value and special performance; the silicon series products comprise five/six coordination organosilicon compounds, organosilicon polymers, silicon carbide, white carbon black and organic and inorganic environment materials with high-efficiency adsorption performance. There are few methods for comprehensively utilizing serpentine tailings and obtaining magnesium-silicon series chemical industrial products.

Disclosure of Invention

The present invention aims to address at least one of the above-mentioned deficiencies of the prior art. For example, an object of the present invention is to provide a method for producing magnesium silicate powder granules whose main crystal phase is olivine from serpentine-containing rocks, waste rocks, and tailings, so as to realize resource utilization of solid wastes.

In order to achieve the above object, an aspect of the present invention provides a method for preparing magnesium silicate powder, including the steps of:

drying, crushing and grinding the raw material containing the serpentine mineral to obtain powder containing the serpentine mineral;

and calcining the powder containing the serpentine mineral to obtain the magnesium silicate powder with the main crystal phase of olivine, wherein the calcining temperature is 850-1200 ℃, and the calcining time is 10 min-2 h.

In an exemplary embodiment of the method for preparing a magnesium silicate powder according to the present invention, the raw material containing a serpentine mineral may be at least one of serpentine, serpentine mill tailings, chrysotile mill tailings, and ultrabedrock type mineral mill tailings.

In an exemplary embodiment of the method for preparing magnesium silicate powder according to the present invention, the drying temperature may be 80 to 105 ℃; the adsorbed water content in the serpentine mineral-containing powder may be less than 4%.

In an exemplary embodiment of the method for preparing magnesium silicate powder according to the present invention, the drying temperature may be 90 to 105 ℃; the content of the absorbed water in the serpentine mineral-containing powder can be 1-2%.

In an exemplary embodiment of the method for preparing magnesium silicate powder according to the present invention, the particle size of the powder containing serpentine mineral may be 0.03mm to 80 mm.

In an exemplary embodiment of the method for preparing magnesium silicate powder according to the present invention, the powder containing serpentine mineral may be calcined in a shaft kiln, a rotary kiln, or a pre-decomposition kiln.

In an exemplary embodiment of the method for preparing magnesium silicate powder according to the present invention, the powder containing serpentine mineral may include 25 to 40% of MgO, 35 to 40% of SiO, by mass₂、2％～10％CaO、5％～15％Fe₂O₃And 1 to 5% of Al₂O₃。

The invention also provides a magnesium silicate powder and particle, which is prepared by the preparation method of the magnesium silicate powder and particle.

In an exemplary embodiment of the magnesium silicate powder, the Mohs hardness of the magnesium silicate powder may be 6.5 to 7.5, the block compressive strength may be 50MPa to 180MPa, and the refractoriness may be 1500 ℃ to 2100 ℃.

In a further aspect, the invention provides the use of magnesium silicate powder as described above as a building aggregate, a polymer filler, a metallurgical cosolvent, an abrasive, a sandblasting material or a raw material for a refractory material.

Compared with the prior art, the beneficial effects of the invention comprise at least one of the following:

(1) according to the invention, the rock, the waste stone and the tailings mainly containing serpentine are used as raw materials to produce the olivine powder particles with the main crystalline phase, so that the resource utilization of solid wastes is realized, and the method has important ecological and sustainable development significance for resource protection, saving and high-value utilization;

(2) the resource utilization of serpentine tailings, waste rocks and tailings has important ecological and environmental significance on the safety, environmental protection, reclamation and greenness of tailings reservoirs;

(3) the novel olivine powder product with the main crystal phase is obtained by processing and treating rocks, waste rocks and tailings mainly containing serpentine as raw materials, has the advantages of simple production process, energy conservation and emission reduction, high product added value, high ecological environmental benefit and the like, and has important significance for developing new material industry and social economy;

(4) the invention decomposes and phase-changes asbestos fiber in rock, waste rock and tailings by roasting treatment to form a non-toxic and harmless magnesium silicate powder product which takes olivine as a main crystal phase, and the powder product can be widely used as a refractory material raw material, a metallurgy cosolvent, building aggregate, an abrasive, a sand blasting material and a polymer filler;

(5) in the preparation process of the magnesium silicate powder, the problems of dust treatment, waste gas utilization, solid waste utilization and the like are considered, three wastes are not discharged in the process flow, the green process flow can be realized, and the basic requirements of environmental protection are met.

Drawings

The above and other objects and/or features of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 shows a microscopic morphology of a magnesium silicate powder/granule product having a particle size of less than 0.15mm according to an exemplary embodiment of the method for preparing a magnesium silicate powder/granule of the present invention.

Detailed Description

Hereinafter, a magnesium silicate powder, a method for preparing the same, and applications thereof according to the present invention will be described in detail with reference to the exemplary embodiments and the accompanying drawings.

It should be noted that, for those skilled in the art, the term "pressure" is used herein to correspond to pressure in part.

At present, the principle of serpentine mineral is mostly not recycled, mainly stockpiling is taken as a main principle, asbestos tailings and tailings which are dangerous to solid waste and are used for stripping waste rocks occupy a large amount of land resources, and potential harm is caused to the surrounding environment. The main crystal phase of the olivine mineral is short in supply in the fields of decolorization, fire resistance, fluxing, building materials, fillers, grinding materials and the like, but the mineral is very limited in distribution and yield.

In order to solve the current situation that serpentine mineral stockpiling is the main situation and simultaneously solve the problem of material supply in the field of mineral resource demand with olivine as the main crystalline phase, the invention takes rocks, waste rocks and tailings mainly containing serpentine as raw materials and produces magnesium silicate powder granules with olivine as the main crystalline phase by a calcination processing technology, thereby having important significance for promoting solid waste recycling and high-value utilization and ecological environment protection.

In order to achieve the above object, one aspect of the present invention provides a method for preparing magnesium silicate powder.

In an exemplary embodiment of the method for preparing magnesium silicate powder according to the present invention, a method for preparing magnesium silicate powder may include the steps of:

(1) drying, crushing and grinding the raw material containing the serpentine mineral to obtain the powder body containing the serpentine mineral.

Wherein the raw material containing the serpentine mineral can be at least one of serpentine, serpentine beneficiation tailings, chrysotile beneficiation tailings and ultrabasic rock type mineral beneficiation tailings.

The serpentine mineral-containing powder can comprise 25-40% of MgO and 35-40% of SiO by mass percentage₂、2％～10％CaO、5％～15％Fe₂O₃And 1 to 5% of Al₂O₃。

Wherein, drying treatment is carried out before crushing, and the drying temperature can be 80-105 ℃ so as to remove the adsorption water of the serpentine mineral. The content of absorbed water of the dried powder is lower than 4%. The excess amount of adsorbed water is not conducive to further pulverization of the sample (i.e., the serpentine mineral-containing material). The adsorption water content of less than 4 percent is beneficial to crushing and roasting detoxification of tailings in the roasting process, and if the water content of the adsorption water exceeds 4 percent, the water evaporation can cause consumption of heat, thereby influencing the combustion condition of the serpentine mineral-containing powder in the calcining furnace in the step (2).

Further, the content of the adsorbed water in the dried serpentine mineral-containing powder/granule may be 1% to 2%. For example, the moisture content absorbed in the serpentine mineral-containing powder or granule after drying may be less than 2% at a drying temperature of 90 ℃ to 105 ℃. Of course, when the drying temperature is 80 to 90 ℃, the adsorbed water content in the serpentine mineral-containing powder after drying may be less than 2% as long as the drying time is sufficient.

Pulverizing to obtain powder containing serpentine mineralThe density was 1.1kg/m³～2.0kg/m³. The particle size of the serpentine mineral-containing powder is optional and includes, but is not limited to, 0.03mm to 80 mm. The crushing is mainly because the crushing is to be crushed to a certain granularity according to the actual product requirements, for example, the particle size of the coarse aggregate used as building aggregate is 4.75 mm-80 mm to replace broken stones, pebbles and the like; as the building fine aggregate, the particle size of the building fine aggregate is controlled to be 0.16-5 mm to replace natural or artificial sandstone; when the polymer product is used as a filler, the particle size of the particles is controlled to be 0.03 mm-0.16 mm.

In addition, the powder can also be used as a refractory material, the grain composition is in accordance with the closest packing, the fine grain is 0.03 mm-0.1 mm, and the grain size is favorable for increasing the driving force of sintering, reducing the diffusion distance of the grains and improving the solubility of the grains.

(2) And (2) putting the powder containing the serpentine mineral obtained in the step (1) into a calcining furnace for heating and calcining, wherein the calcining temperature is 850-1200 ℃, and the powder containing the serpentine mineral is calcined for 10 min-2 h to obtain the magnesium silicate powder with the main crystal phase of olivine.

The serpentine mineral-containing powder can be calcined in a vertical kiln, a rotary kiln or a pre-decomposition kiln.

The calcination temperature is 850-1200 ℃, and the calcination time is 10 min-2 h because: if the calcining temperature is lower than 850 ℃ or the calcining time is lower than 10min, the serpentine-containing mineral cannot be completely converted into the forsterite phase; when the calcining temperature is higher than 1200 ℃, the serpentine-containing mineral starts to sinter and melt, the serpentine-containing mineral has crystal phase transformation, but the subsequent utilization value is influenced, and meanwhile, the high-temperature phase transformation needs to consume a large amount of heat and does not meet the requirements of energy conservation and environmental protection; after the calcination time is more than 2h, the serpentine-containing mineral has completed crystal phase conversion, and the calcination time is increased, so that energy is wasted.

For example, the calcination temperature may be 900 ℃, 1000 ℃, 1100 ℃, 1200 ℃ or the like, and the calcination time may be 10min, 30min, 50min, 70min, 90min, 110min or the like.

Furthermore, the heating rate is 3 ℃/min to 20 ℃/min. If the temperature rise speed in the calcining process is too low or the calcining time is too long, the production efficiency is low, the production cost is increased, energy waste is caused, and the cycle is prolonged; if the temperature rise rate is too high or the calcination time is too short, the crystal phase conversion effect is poor and insufficient. For example, the temperature rise rate can be 3 ℃/min, 5 ℃/min, 8 ℃/min, 10 ℃/min, 15 ℃/min, 20 ℃/min, and the like.

The magnesium silicate powder particle prepared by the method has the main crystal phase of olivine, but can be used for producing series products in different fields by adjusting the process parameters such as the particle size of the powder particle, the calcination temperature, the calcination time and the like, and has the advantages of simple process, safety and environmental protection.

The invention also provides a magnesium silicate powder and particle, which is prepared by the preparation method of the magnesium silicate powder and particle.

The magnesium silicate powder with olivine as the main crystal phase obtained in the embodiment can be yellow gray to yellow green, the Mohs hardness can be 6.5 to 7.5, the block compressive strength can be 50MPa to 180MPa, the refractoriness can be 1500 ℃ to 2100 ℃, and the magnesium silicate powder can be used for refractory material raw materials, metallurgy cosolvent, building aggregate, abrasive materials, sand blasting materials and polymer fillers.

Preferably, the magnesium silicate powder granule with the main crystal phase of olivine has a macroscopic structure of yellow brown powder and a microscopic appearance of plate-shaped and sheet-shaped.

Compared with the traditional building aggregate, the magnesium silicate powder particle taking the main crystal phase as the olivine has higher hardness, and simultaneously compared with the complexity of the raw materials of the traditional building aggregate, the magnesium silicate powder particle taking the main crystal phase as the olivine has high raw material uniformity, and the built building has higher mechanical stability and structural stability.

Compared with the traditional refractory material, the magnesium silicate powder body taking the main crystal phase as olivine has higher refractoriness which can reach more than 2000 ℃, high-temperature strength and stronger resistance to alkaline slag.

Compared with the traditional polymer filler, the magnesium silicate powder particle with the main crystal phase as olivine can improve the rigidity of the polymer material and the heat resistance of the filler material, and can also improve the creep resistance of the polymer material.

In a further aspect, the invention provides the use of magnesium silicate powder as described above as a building aggregate, a polymer filler, a metallurgical cosolvent, an abrasive, a sandblasting material or a raw material for a refractory material.

For a better understanding of the above-described exemplary embodiments of the present invention, reference is made to the following description taken in conjunction with the accompanying drawings and specific examples.

Example 1

A preparation method of magnesium silicate powder can comprise the following steps:

and S1, selecting chrysotile mill tailings as a raw material containing the serpentine mineral, and drying, crushing and crushing the chrysotile mill tailings to obtain powder mainly containing the serpentine mineral.

Wherein, the chemical composition of the serpentine mineral-containing powder comprises the following components in percentage by mass: 38% MgO and 36% SiO₂、9％CaO、12％Fe₂O₃And 5% Al₂O₃。

After crushing, the particle size of the serpentine mineral-containing powder is 0.05-0.15 mm.

S2, placing the powder containing the serpentine mineral obtained in the step S1 into a rotary kiln, and heating and calcining the powder at 900 ℃ for 50min to obtain the magnesium silicate powder with the main crystal phase of olivine.

After the calcination treatment, the particle size of the obtained magnesium silicate powder product is less than 0.15mm, and the microscopic morphology of the product is shown in figure 1.

The magnesium silicate powder with olivine as main crystal phase obtained in the present example can be used as filler for polymer products.

Example 2

A preparation method of magnesium silicate powder can comprise the following steps:

s1, selecting serpentine as a raw material containing serpentine minerals, drying and crushing the serpentine to obtain powder mainly containing the serpentine minerals.

Wherein, the chemical composition of the serpentine mineral-containing powder comprises the following components in percentage by mass: 40% MgO and 39% SiO₂、7％CaO、10％Fe₂O₃And 4% Al₂O₃。

After crushing treatment, the particle size of the serpentine mineral-containing powder is 5 mm-30 mm.

S2, placing the powder containing the serpentine mineral obtained in the step S1 into a pre-decomposition kiln, and heating and calcining at 950 ℃ for 30min to obtain the magnesium silicate powder with the main crystal phase of olivine.

After calcination treatment, the obtained magnesium silicate powder particle product has the particle size of 5-30 mm, and can be used as a coarse aggregate of building aggregate to replace broken stones, pebbles and the like.

Example 3

A preparation method of magnesium silicate powder can comprise the following steps:

s1, selecting serpentine beneficiation tailings as a raw material containing serpentine minerals, and drying and crushing the serpentine beneficiation tailings to obtain powder mainly containing the serpentine minerals.

Wherein, the chemical composition of the serpentine mineral-containing powder comprises the following components in percentage by mass: 36% MgO and 38% SiO₂、8％CaO、15％Fe₂O₃And 3% Al₂O₃。

After crushing treatment, the particle size of the serpentine mineral-containing powder is 0.15 mm-5 mm.

S2, placing the powder containing the serpentine mineral obtained in the step S1 into a pre-decomposition kiln, and heating and calcining at 1050 ℃ for 13min to obtain the magnesium silicate powder with the main crystal phase of olivine.

After calcination treatment, the obtained magnesium silicate powder particle product has the particle size of 0.15-5 mm, and can be used as building fine aggregate to replace natural or artificial sandstone and the like.

In summary, the beneficial effects of the invention include at least one of the following:

(1) the invention takes the rocks, waste rocks and tailings mainly containing serpentine as raw materials to produce olivine powder particles with the main crystalline phase, realizes the resource utilization of solid wastes, and has important ecological and sustainable development significance for resource protection, saving and high-value utilization.

(2) The resource utilization of serpentine tailings, waste rocks and tailings has important ecological and environmental significance for the safety, environmental protection, reclamation and greening of tailings reservoirs.

(3) The novel olivine powder product with the main crystal phase is obtained by processing and treating rocks, waste rocks and tailings mainly containing serpentine as raw materials, has the advantages of simple production process, energy conservation and emission reduction, high product added value, high ecological environmental benefit and the like, and has important significance for developing new material industry and social economy.

(4) The present invention decomposes and phase-converts asbestos fiber in rock, waste rock and tailings by roasting treatment to form non-toxic and harmless magnesium silicate powder and particle products which take olivine as a main crystal phase, and the powder and particle products can be widely used as refractory material raw materials, metallurgy cosolvent, building aggregate, abrasive, sand blasting material and polymer filler.

(5) In the preparation process of the magnesium silicate powder, the problems of dust treatment, waste gas utilization, solid waste utilization and the like are considered, three wastes are not discharged in the process flow, the green process flow can be realized, and the basic requirements of environmental protection are met.

Although the present invention has been described above in connection with the exemplary embodiments and the accompanying drawings, it will be apparent to those of ordinary skill in the art that various modifications may be made to the above-described embodiments without departing from the spirit and scope of the claims.