阅读说明：本技术 一种纳米金属硅粒的生产方法 (Production method of nano metal silicon particles ) 是由 王浩 王永 李灿华 徐文珍 于 2019-11-28 设计创作，主要内容包括：本发明公开了一种纳米金属硅粒的生产方法,将原料硅泥通过预脱水或晾干处理,再经破碎机破碎后加入粘合剂混匀,混合料由辅送带送入造粒机内造粒,该辅送带终端设置磁头除铁与磁性材料杂质,之后将硅粒由输送带送入烘干机内烘干干燥,最后装袋制得纳米金属硅粒。所得纳米金属硅粒呈粒状,直径在3-8mm,长度在5-25mm,水份含量0.5-8%；杂质SiO<Sub>2</Sub>等含量1-12%；单质硅含量72-98%。本发明彻底改变了该工艺生产过程,通过纯物理过程实现了低能耗、低污染,切实高效利用了硅泥这种工业副产品的潜在价值,把硅泥深加工成纳米金属硅粒,最大限度的做到了节能减排和循环利用,本专利发明转化到工业化生产中具有一定的经济价值和社会效益。(The invention discloses a method for producing nano metal silicon particles, which comprises the steps of pre-dehydrating or airing raw material silicon mud, crushing the raw material silicon mud by a crusher, adding an adhesive into the crushed raw material silicon mud, uniformly mixing the crushed raw material silicon mud and the adhesive, feeding the mixed material into a granulator for granulation by an auxiliary conveyor belt, arranging a magnetic head at the terminal of the auxiliary conveyor belt for removing iron and impurities of a magnetic material, feeding the silicon particles into a dryer for drying by the conveyor belt, and finally bagging the silicon particles to obtain the nano metal silicon particles. The obtained nano metal silicon particles are granular, the diameter is 3-8mm, the length is 5-25mm, and the water content is 0.5-8%; impurity SiO 2 Equal content is 1-12%; the content of the simple substance silicon is 72-98%. The invention thoroughly changes the production process of the process, realizes low energy consumption and low pollution through a pure physical process, and practically and efficiently utilizes the silicon sludgeThe silicon mud is deeply processed into nano metal silicon particles, so that energy conservation, emission reduction and recycling are realized to the maximum extent, and the invention has certain economic value and social benefit when being converted into industrial production.)

1. A production method of nano metal silicon particles is characterized in that raw material silicon mud is subjected to pre-dehydration or air drying treatment, is crushed by a crusher and then is added with an adhesive to be mixed uniformly, the mixture is sent into a granulator for granulation through an auxiliary conveyor belt, a magnetic head is arranged at the terminal of the auxiliary conveyor belt to remove iron and impurities of magnetic materials, then the silicon particles are sent into a dryer for drying through the conveyor belt, and finally the nano metal silicon particles are obtained by bagging;

wherein the raw material silicon sludge is ultrafine dust generated by cutting monocrystalline or polycrystalline silicon wafers during the production of silicon wafers, and is obtained by washing and precipitating;

wherein, the nano metal silicon particles are granular, the diameter is 3-8mm, the length is 5-25mm, and the water content is 0.5-8%; impurity SiO₂The equal mass percentage is 1-12%; the weight percentage of the simple substance silicon is 72-98%.

2. The method for producing nano-sized metallic silicon particles as recited in claim 1, wherein the moisture content of the raw material silicon sludge is 25 to 48%.

3. The method for producing nano-sized metallic silicon particles as claimed in claim 1, wherein the moisture content of the silicon sludge is controlled to be 20-35% during the pre-dehydration or air-drying treatment.

4. The method for producing nano-sized metallic silicon particles as claimed in claim 1, wherein the particle fineness of the silicon sludge during the crushing process is controlled to 5.5 to 10.5 μm.

5. The method for producing nano-sized metallic silicon particles as claimed in claim 1, wherein the dry powder binder is added to the silicon sludge in a proportion of 0-3% before the granulation, and the mixture is stirred and mixed uniformly.

6. The method for producing nano-sized metallic silicon particles as claimed in claim 5, wherein the dry powder binder is selected from one or more of bentonite, industrial starch, sodium carboxymethyl cellulose and cellulose.

7. The method as claimed in claim 1, wherein the drying temperature of the dryer is controlled at about 100-160 ℃.

8. The method for producing nano-sized metallic silicon particles as claimed in claim 1, wherein the drying process ensures that the material is dried at low ambient temperature until the moisture content is in the range of 0.5-8%.

9. The method for producing nano-sized metallic silicon particles as set forth in claim 1, wherein the product is packaged while ensuring airtight sealing of the package.

Technical Field

The invention belongs to the technical field of silicon material preparation, and particularly relates to a production method of nano metal silicon particles.

Background

The production of the photovoltaic module comprises four key links: production of polycrystalline silicon, slicing of ingot, and production of batteries and components. Among them, diamond wire slicing is widely used in monocrystalline silicon enterprises. During the process of cutting monocrystalline silicon and polycrystalline silicon, the diamond wire can generate a large amount of cut silicon powder, and the average size of the silicon powder is 5.5-10.5 mu m; in addition, the cutting silicon powder contains a large amount of cutting liquid. The powder is settled by flocculation and then collected by a filter press, finally obtaining a "mud cake", herein referred to as "silica mud". Because the silicon powder in the silicon mud has small size and contains moisture and non-silicon impurities; most enterprises have no recovery capability for the silicon sludge and no economic value for recycling. Therefore, in the photovoltaic industry, a large amount of silicon mud is generated in the production process, and the problem which cannot be solved in the industry is solved.

The application mode of the byproduct silicon sludge in the photovoltaic industry in the current market is as follows: the silicon ingot is melted and recrystallized into the silicon ingot by the intermediate frequency furnace, the standard requirement of the process on the raw material of the silicon mud is high, namely the content of simple substance silicon in the dried silicon mud is 95-98%, so that the selection of the silicon mud is limited, a large amount of dust can be generated in the process of processing and producing the silicon ingot, whether the silicon ingot is in the drying process or in the smelting process of the melting furnace, and serious dust pollution is caused to the environment.

Disclosure of Invention

The invention aims to make up the defects of the prior art and provides a method for producing nano metal silicon particles.

In order to achieve the above object, the present invention provides the following technical solutions:

a production method of nano metal silicon particles comprises the steps of carrying out pre-dehydration or air drying treatment on raw material silicon mud, crushing the raw material silicon mud by a crusher, feeding the crushed raw material silicon mud into a granulator for granulation, arranging a magnetic head at the terminal of an auxiliary belt for removing iron and impurities of magnetic materials, feeding silicon particles into a dryer for drying by a conveyer belt, and finally bagging to obtain nano metal silicon particles;

wherein the raw material silicon sludge is ultrafine dust generated by cutting monocrystalline or polycrystalline silicon wafers during the production of silicon wafers, and is obtained by washing and precipitating;

wherein, the nano metal silicon particles are granular, the diameter is 3-8mm, the length is 5-25mm, and the water content is 0.5-8%; impurity SiO₂The equal mass percentage is 1-12%; the weight percentage of the simple substance silicon is 72-98%.

Further, the water content of the raw material silicon mud is 25-48%.

Furthermore, in the pre-dehydration or airing treatment process, the water content of the silicon mud is controlled to be 20-35%.

Furthermore, the particle fineness of the silicon mud is controlled to be 5.5-10.5 μm in the crushing process.

The dust in the silicon mud treatment process leaks and diffuses to cause dust pollution to the environment, and the water content of the silicon mud is particularly controlled to be kept between 20 and 35 percent in the mixing, grinding, crushing and stirring processes.

When the water content of the silicon mud is 20-35%, the silicon mud is sent into a crusher, the materials are fragile at the moment, but although dust is extremely small and is not easy to diffuse, in consideration of dust pollution, equipment with good environmental protection and crushing effects can be selected.

Further, before granulation, a dry powder adhesive is added into the silicon mud according to the proportion of 0-3%, and the mixture is stirred and mixed uniformly, wherein the dry powder adhesive is a substance with good adhesive property and plays a role of connecting objects by surface adhesion through adhesive force and cohesive force.

Preferably, the dry powder binder is selected from one or more of bentonite, industrial starch, sodium carboxymethyl cellulose and cellulose.

According to actual production, granulation can be completed without adding a dry powder binder, and only the pressure resistance of the silicon particles is weak, and the pressure resistance of the silicon particles is enhanced along with the increase of the binder.

Although granulation is a physical process, high temperature oxidation and deflagration of elemental silicon occur during calendering and extrusion, and for this reason, the selection of a granulator is very important, and equipment with high granulation speed and low temperature rise of extruded materials is selected.

Further, the drying temperature of the dryer is controlled at 160 ℃ and 100 ℃.

The temperature of the dryer is controlled to be low or not too high, otherwise, the silicon particles are easy to detonate and oxidize.

Furthermore, the materials are dried at low ambient temperature in the drying process until the moisture content is in the range of 0.5-8%.

Further, when the product is bagged, the airtight sealing package is ensured.

When the product is packaged, the packaging bag needs to be airtight, and meanwhile, the product needs to be packaged in a sealing mode, otherwise, the product can absorb moisture in the air and be oxidized.

The nano metal silicon particles obtained by the production method of the nano metal silicon particles can partially or completely replace ferrosilicon and industrial silicon, are applied to the production industries of metallurgical casting, silicon-aluminum alloy and silicon-magnesium alloy materials, and can also be used for steel-making deoxidation, silicon increasing and silicon-series alloy smelting.

The invention has the advantages that:

1. the method thoroughly changes the technological production process of silicon mud utilization, realizes low energy consumption and low pollution through a pure physical process, practically and efficiently utilizes the potential value of silicon mud which is an industrial byproduct, and deeply processes the silicon mud into nano metal silicon particles.

2. The waste silicon sludge is recycled, and the problem of environmental pollution caused by the silicon sludge is solved.

3. Energy conservation, emission reduction and cyclic utilization are realized to the maximum extent, and secondary pollution is avoided.

4. The content of simple substance silicon in the produced nano metal silicon particles reaches 72-98%, and the nano metal silicon particles have fewer impurities, so that the requirement of subsequent processing and utilization is met.

5. The production cost is greatly reduced, and the conversion into industrial production has certain economic value and social benefit.

Drawings

FIG. 1 is a flow chart of the process for producing nano-sized metal silicon particles according to the present invention.

Detailed Description

The technical scheme of the invention is further explained by combining the specific examples as follows: