阅读说明：本技术 一种二次铝灰渣无需预处理制备泡沫微晶玻璃的方法 (Method for preparing foam glass ceramics by secondary aluminum ash without pretreatment ) 是由 张俊杰 张深根 刘波 于 2021-09-24 设计创作，主要内容包括：本发明公开了一种二次铝灰渣无需预处理制备泡沫微晶玻璃的方法,属于固废综合利用领域。将二次铝灰渣、废玻璃、粘度调节剂以及稳泡剂球磨后,经成型、同步发泡析晶获得泡沫微晶玻璃。废玻璃及二次铝灰渣中的氧化铝为泡沫微晶玻璃提供玻璃网络的硅源和铝源,粘度调节剂提供钙源。所述稳泡剂可改变所述泡沫微晶玻璃熔体性能,稳定气泡结构。本发明利用二次铝灰渣中的氧化铝为泡沫微晶玻璃提供玻璃网络体,无需除氮、除盐预处理,以二次铝灰渣中的氮化铝作为发泡剂,将其中的钾盐和钠盐转化为玻璃相,氟化物作为助熔剂,不仅节能降耗、经济效益高、减少了环境污染,而且实现了二次铝灰渣的无害化处置、高值化利用,具有流程短、易于产业化的优点。(The invention discloses a method for preparing foam glass ceramics by secondary aluminum ash without pretreatment, belonging to the field of solid waste comprehensive utilization. And (3) performing ball milling on secondary aluminum ash, waste glass, a viscosity regulator and a foam stabilizer, and performing molding and synchronous foaming crystallization to obtain the foam glass ceramics. Alumina in the waste glass and the secondary aluminous ash provides a silicon source and an aluminum source of a glass network for the foam glass ceramics, and a calcium source is provided by the viscosity regulator. The foam stabilizer can change the performance of the foam microcrystalline glass melt and stabilize the structure of bubbles. The invention utilizes the alumina in the secondary aluminum ash slag to provide a glass network body for the foam glass ceramics, does not need nitrogen removal and desalting pretreatment, takes the aluminum nitride in the secondary aluminum ash slag as a foaming agent, converts sylvite and sodium salt in the foaming agent into a glass phase, and takes fluoride as a fluxing agent, thereby not only saving energy, reducing consumption, having high economic benefit and reducing environmental pollution, but also realizing harmless disposal and high-valued utilization of the secondary aluminum ash slag, and having the advantages of short flow and easy industrialization.)

1. A method for preparing foam glass ceramics by secondary aluminum ash without pretreatment is characterized in that the foam glass ceramics is obtained by ball milling secondary aluminum ash, waste glass, a viscosity regulator and a foam stabilizer, molding and synchronous foaming crystallization; the waste glass and alumina in the secondary aluminum ash slag are used as a silicon source and an aluminum source of a glass network for the foam glass ceramics, the secondary aluminum ash slag is used as a foaming agent, a nucleating agent and a fluxing agent for preparing the foam glass ceramics, the viscosity regulator is used as a calcium source for the foam glass ceramics, and the foam stabilizer can change the melt performance of the foam glass ceramics and stabilize the bubble structure.

2. The method for preparing the foam glass-ceramic by using the secondary aluminum ash without pretreatment as claimed in claim 1, wherein the raw material ratio is 25-40 wt.% of the secondary aluminum ash, 30-40 wt.% of waste glass, 15-30 wt.% of viscosity regulator and 5-10 wt.% of foam stabilizer.

3. The method for preparing the foam glass-ceramics without the pretreatment of the secondary aluminum ash according to claim 1, wherein the viscosity regulator is one or more of quicklime, calcium carbonate and borax; the foam stabilizer is trisodium phosphate (Na)₃PO₄)。

4. The method for preparing the foam glass ceramics by the secondary aluminum ash without pretreatment according to claim 1, which comprises the following specific steps:

s1, ball milling: ball-milling secondary aluminum ash, waste glass, a viscosity regulator and a foam stabilizer to obtain a uniform mixture;

s2, molding: pouring the mixture into a mold, and pressing and molding the mixture by using a press;

s3, synchronous foaming and crystallization: and carrying out heat treatment on the raw materials subjected to press forming to obtain the foam glass ceramics.

5. The method for preparing the foam glass-ceramics without the pretreatment of the secondary aluminum ash as claimed in claim 4, wherein the ball milling process parameter is ball milling rotation speed of 100-500 rpm for 1-4h, and the mixture is sieved by a 100-mesh sieve.

6. The method for preparing the foam glass-ceramic by using the secondary aluminum ash without pretreatment as claimed in claim 4, wherein the forming comprises the following steps: the parameter is pressure of 20-30 MPa, and the pressure is kept for 20-60 s.

7. The method for preparing the foam glass-ceramics without the pretreatment of the secondary aluminum ash as claimed in claim 4, wherein the heat treatment system of the synchronous foaming crystallization is heat preservation for 20-60 min at 1000-1350 ℃.

Technical Field

The invention belongs to the field of comprehensive utilization of solid waste, and particularly relates to a method for preparing foam glass ceramics by secondary aluminum ash without pretreatment.

Background

Aluminous ash is a dangerous solid waste formed by the reaction of molten aluminum and air during aluminum smelting, and the emission per year is conservative estimated to be more than 300 million tons. The aluminous ash is divided into primary aluminous ash and secondary aluminous ash, the primary aluminous ash contains 30-70% of aluminum, metal aluminum can be generally recycled through secondary smelting, and the slag generated in the process is called secondary aluminous ash. The secondary aluminum ash contains water-soluble chloride (such as NaCl and KCl), trace heavy metals and toxic ions (F)^-，CN^-) When the secondary aluminum ash slag is easy to enter into the ecological environment, toxic and flammable gas can be generated when the secondary aluminum ash slag is exposed in the external environment, and the serious influence is caused on the health and the environment of people, so the harmless treatment of the secondary aluminum ash slag needs to be solved urgently.

At present, harmless treatment and resource utilization in secondary aluminum ash slag mainly focus on using hydrometallurgy and a heat treatment method. Such as water washing, acid leaching and alkaline leaching, and realizes the recovery of valuable elements in the aluminous ash. The water washing is usually used as a pretreatment process for improving the recovery rate of aluminum, can recover salt in the aluminum ash, and can hydrolyze aluminum nitride at the same time, thereby reducing the influence of impurities on the leaching process. The alkaline leaching and acid leaching mainly promote aluminum to enter leaching solution in the form of ions, and valuable products such as activated alumina and eta-Al are obtained by the processes of coprecipitation, purification, roasting and the like₂O₃And the like, thereby achieving the purpose of recovering aluminum. Also have studied the advantagesThe secondary aluminum ash slag is used for manufacturing cement fillers, geopolymers and concrete blocks. But chloride existing in the secondary aluminum ash has interference effect on hydration reaction of cement, so that the mechanical property of the building material is reduced; aluminum nitride also decomposes ammonia over time. Although water washing pretreatment can be used for removing chloride salt, aluminum nitride can still exist in the building material due to incomplete hydrolysis, thereby releasing ammonia gas, and the requirement of safe disposal is not met.

Chinese invention patent (CN 112794353A) discloses a method and a device for preparing polyaluminium chloride by recycling aluminum ash, which obtains the polyaluminium chloride by hydrolysis, drying, acid dissolution, alkali dissolution and filtration centrifugation, but has large water consumption and generates a large amount of waste alkali and waste acid.

The Chinese invention patent (CN 112553470A) discloses a method for recovering aluminum hydroxide powder by using titanium white waste acid and secondary aluminum ash, nitrogen and salt are removed by water leaching, and the secondary aluminum ash residue is subjected to acid leaching by using the titanium white waste acid and part of concentrated sulfuric acid as leaching solutions, but the acid consumption is large and the process is complex.

The Chinese invention patent (CN 108275708B) discloses a secondary aluminum ash resource utilization method, which comprises the steps of grinding secondary aluminum ash into powder, then flushing the powder with steam under a high pressure condition, recovering nitrogen and hydrogen fluoride, carrying out suction filtration, evaporation and crystallization on high-concentration aluminum mortar, recovering chlorine salt, roasting a filtered solid phase at 1300-1500 ℃ to recover fluoride, adding an alkali flux to carry out impurity removal smelting at 800-1100 ℃, then adding liquid to carry out solid-liquid separation, and finally calcining the leachate at more than 1000 ℃ to obtain aluminum oxide.

Chinese patent of invention (CN 108383142B) discloses a method for producing alumina by recycling regenerated aluminum ash, which comprises the steps of grinding, cleaning, low-temperature alkaline smelting, water leaching, leaching solution impurity removal, precipitation of aluminum hydroxide and high-temperature roasting to obtain alumina, but generates a large amount of wastewater containing F, Cl and ammonia nitrogen.

Chinese patent of invention (CN 106478020A) discloses a method for preparing baking-free bricks by using waste aluminum ash, which obtains the baking-free bricks by crushing, mixing, molding and curing the waste aluminum ash and raw materials such as water-quenched slag, silica fume, anhydrous calcium sulfate and the like, but the problem that aluminum nitride in the aluminum ash is hydrolyzed under the condition of water existence and generates ammonia gas is not solved.

Chinese patent of invention (CN 110563336A) discloses a method for preparing glass ceramics by aluminum ash without desalting and removing nitrogen, which is characterized in that secondary aluminum ash generated after aluminum is extracted from calcium aluminate is mixed with quick lime, waste glass and the like to prepare glass ceramics, the aluminum ash is converted into glass at 1200-1500 ℃, and then nucleation-crystallization heat treatment is carried out to obtain the glass ceramics, but the method needs two heat treatments and the temperature can reach as high as 1500 ℃, the energy consumption is high, the heat treatment process is complex, and the gas generated by aluminum nitride in the aluminum ash is not effectively utilized.

Disclosure of Invention

The invention aims to fully utilize the intrinsic characteristics of secondary aluminum ash slag and provide a method for preparing foam glass ceramics by the secondary aluminum ash slag without pretreatment, wherein the harmless treatment and the value increasing treatment of the secondary aluminum ash slag are realized by taking the existing aluminum nitride as a foaming component, taking alumina as a glass network body and taking fluoride as a fluxing agent.

The invention is realized by the following technical scheme:

a method for preparing foam glass ceramics by secondary aluminum ash without pretreatment comprises the steps of ball-milling the secondary aluminum ash, waste glass, a viscosity regulator and a foam stabilizer, molding, synchronously foaming and crystallizing to obtain the foam glass ceramics; the waste glass and alumina in the secondary aluminum ash slag are used as a silicon source and an aluminum source of a glass network for the foam glass ceramics, the secondary aluminum ash slag is used as a foaming agent, a nucleating agent and a fluxing agent for preparing the foam glass ceramics, the viscosity regulator is used as a calcium source for the foam glass ceramics, and the foam stabilizer can change the melt performance of the foam glass ceramics and stabilize the bubble structure.

Furthermore, the raw material ratio is 25-40 wt.% of secondary aluminum ash, 30-40 wt.% of waste glass, 15-30 wt.% of viscosity regulator and 5-10 wt.% of foam stabilizer.

Further, the viscosityThe regulator is one or more of quicklime, calcium carbonate and borax; the foam stabilizer is trisodium phosphate (Na)₃PO₄)。

A method for preparing foam glass ceramics by secondary aluminum ash without pretreatment comprises the following specific steps:

s1, ball milling: ball-milling secondary aluminum ash, waste glass, a viscosity regulator and a foam stabilizer to obtain a uniform mixture;

s2, molding: pouring the mixture into a mold, and pressing and molding the mixture by using a press;

s3, synchronous foaming and crystallization: and carrying out heat treatment on the raw materials subjected to press forming to obtain the foam glass ceramics.

Further, the ball milling process parameter is that the ball milling rotating speed is 100-500 rpm for 1-4 hours, and the mixture is sieved by a 100-mesh sieve.

Furthermore, the molding parameter is pressure of 20-30 MPa, and the pressure is kept for 20-60 s.

Further, the synchronous foaming crystallization heat treatment system is that the temperature is kept for 20-60 min at 1000-1350 ℃.

The principle of the invention is as follows:

(1) the mechanical ball milling process causes the temperature and the pressure of an impact friction point to rise, causes the crystal defect diffusion and the atom local rearrangement of the mixture, reduces the bonding energy of oxygen, nitrogen, silicon and aluminum, improves the specific surface area of raw material particles, promotes foaming components in secondary aluminum ash slag to easily generate chemical reactions such as oxidation, hydrolysis and the like, simultaneously promotes the particle size reduction of the mixture in the ball milling process, increases the stacking density of the particles, uniformly distributes the foaming components, the viscosity regulator, the foam stabilizer and the like, and is favorable for the uniform diffusion of gas after forming a melt.

(2) The waste glass is firstly used for forming a melt at high temperature, and simultaneously, the potassium salt, sodium salt and fluoride in the secondary aluminum ash are used for reducing the melting point of the materials, so that the secondary aluminum ash and the viscosity regulator form a melt zone to promote the foam stabilizer to form [ PO ]₄]Tetrahedrons complement the glass network structure and retain bubbles within the melt.

(3) The trace heavy metals in the secondary aluminum ash are used as nucleating agents of the glass body, so that the crystal phase in the raw materials is promoted to be separated out, and the mechanical property of the product is enhanced.

(4) The gas temperature (800-.

The invention has the beneficial technical effects that:

(1) according to the method, the secondary aluminum ash and the waste glass are used as a silica-aluminum source, the aluminum nitride existing in the secondary aluminum ash and the waste glass is used as a foaming component, so that the consumption of a foaming agent is reduced, and the problem of removing nitrogen from the secondary aluminum ash is solved;

(2) the method realizes green and efficient circulation of all components of the secondary aluminum ash;

(3) the method has the advantages of simple process, low cost, no pollution and wide applicability, and is easy for industrialization.

Drawings

FIG. 1 is a schematic flow chart of a method for preparing foam glass ceramics by using secondary aluminum ash without pretreatment in the embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

On the contrary, the invention is intended to cover alternatives, modifications, equivalents and alternatives which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, certain specific details are set forth in order to provide a better understanding of the present invention. It will be apparent to one skilled in the art that the present invention may be practiced without these specific details.

Example 1

Ball-milling 40 wt.% secondary aluminous ash, 30 wt.% waste glass, 20 wt.% viscosity regulator and 10 wt.% foam stabilizer in a mechanical ball mill for 2h, setting the ball-milling rotation speed at 400rpm, keeping the mixture at the pressure of 20MPa for 40s, and then keeping the temperature of the pressed sample at 1100 ℃ for 25min to obtain the foam microcrystalline glass with the porosity of 65% and the compressive strength of 8.23 MPa.

Example 2

And (3) carrying out ball milling on 38 wt.% secondary aluminous ash, 32 wt.% waste glass, 25 wt.% viscosity regulator and 5 wt.% foam stabilizer in a mechanical ball mill for 3h, setting the ball milling rotation speed at 400rpm, keeping the mixture at the pressure of 22MPa for 30s, and then keeping the temperature of the pressed sample at 1150 ℃ for 30min to obtain the foamed microcrystalline glass with the porosity of 71% and the compressive strength of 7.40 MPa.

Example 3

Ball-milling 34 wt.% secondary aluminous ash, 35 wt.% waste glass, 22 wt.% viscosity regulator and 9 wt.% foam stabilizer in a mechanical ball mill for 1h, setting the ball-milling speed at 500rpm, keeping the mixture at 23MPa for 32s, and then keeping the temperature of the pressed sample at 1180 ℃ for 35min to obtain the foam microcrystalline glass with the porosity of 74.2% and the compressive strength of 7.12 MPa.

Example 4

33 wt.% secondary aluminous ash, 39 wt.% waste glass, 19 wt.% viscosity regulator and 9 wt.% foam stabilizer are subjected to ball milling for 1.5h in a mechanical ball mill, the ball milling rotating speed is set to be 450rpm, the mixture is kept for 37s under the pressure of 24MPa, and then the pressed sample is kept at 1050 ℃ for 40min, so that the porosity of the foamed microcrystalline glass is 61.23%, and the compressive strength is 14.33 MPa.

Example 5

Ball-milling 28 wt.% secondary aluminous ash, 40 wt.% waste glass, 24 wt.% viscosity regulator and 8 wt.% foam stabilizer in a mechanical ball mill for 2.5h, setting the ball-milling rotation speed at 480rpm, keeping the mixture at the pressure of 25MPa for 34s, and then keeping the temperature of the pressed sample at 1080 ℃ for 45min to obtain the foamed microcrystalline glass with the porosity of 62.35% and the compressive strength of 12.53 MPa.

Example 6

39 wt.% secondary aluminous ash, 38 wt.% waste glass, 15 wt.% viscosity regulator and 7 wt.% foam stabilizer are ball-milled in a mechanical ball mill for 3.5h, the ball-milling rotating speed is set to be 200rpm, the mixture is kept for 20s under the pressure of 30MPa, and then the pressed sample is kept at 1120 ℃ for 28min, so that the porosity of the foamed microcrystalline glass is 72.25%, and the compressive strength is 14.14 MPa.

Example 7

And (3) ball-milling 28 wt.% secondary aluminous ash, 37 wt.% waste glass, 29 wt.% viscosity regulator and 6 wt.% foam stabilizer in a mechanical ball mill for 4h, setting the ball-milling rotation speed at 100rpm, keeping the mixture at the pressure of 28MPa for 40s, and then keeping the temperature of the pressed sample at 1000 ℃ for 60min to obtain the foam microcrystalline glass with the porosity of 55.12% and the compressive strength of 15 MPa.

Example 8

And (3) ball-milling 37 wt.% secondary aluminous ash, 36 wt.% waste glass, 17 wt.% viscosity regulator and 10 wt.% foam stabilizer in a mechanical ball mill for 2h, setting the ball-milling speed at 500rpm, keeping the mixture at the pressure of 21MPa for 42s, and then keeping the temperature of the pressed sample at 1080 ℃ for 55min to obtain the foamed microcrystalline glass with the porosity of 58.02% and the compressive strength of 13.45 MPa.

Example 9

And (3) ball-milling 36 wt.% secondary aluminous ash, 34 wt.% waste glass, 20 wt.% viscosity regulator and 10 wt.% foam stabilizer in a mechanical ball mill for 3h, setting the ball-milling rotation speed at 480rpm, keeping the mixture at the pressure of 29MPa for 55s, and then keeping the temperature of the pressed sample at 1040 ℃ for 57min to obtain the foamed microcrystalline glass with the porosity of 57.12% and the compressive strength of 11.20 MPa.

Example 10

Ball-milling 35 wt.% secondary aluminous ash, 31 wt.% waste glass, 26 wt.% viscosity regulator and 8 wt.% foam stabilizer in a mechanical ball mill for 2.8h, setting the ball-milling rotation speed at 250rpm, keeping the mixture at a pressure of 27MPa for 50s, and then keeping the temperature of the pressed sample at 1020 ℃ for 59min to obtain the foamed microcrystalline glass with the porosity of 60.12% and the compressive strength of 13.02 MPa.

Example 11

Ball-milling 25 wt.% secondary aluminous ash, 35 wt.% waste glass, 30 wt.% viscosity regulator and 10 wt.% foam stabilizer in a mechanical ball mill for 1.8h, setting the ball-milling rotation speed at 200rpm, keeping the mixture at 28MPa for 20s, and then keeping the pressed sample at 1060 ℃ for 32min to obtain the foamed microcrystalline glass with the porosity of 65.21% and the compressive strength of 14.02 MPa.

Example 12

And (3) ball-milling 26 wt.% secondary aluminous ash, 36 wt.% waste glass, 28 wt.% viscosity regulator and 10 wt.% foam stabilizer in a mechanical ball mill for 4h, setting the ball-milling rotation speed at 300rpm, keeping the mixture at the pressure of 24MPa for 38s, and then keeping the temperature of the pressed sample at 1140 ℃ for 28min to obtain the foamed microcrystalline glass with the porosity of 67.12% and the compressive strength of 9.45 MPa.

Example 13

And (3) ball-milling 27 wt.% secondary aluminous ash, 33 wt.% waste glass, 30 wt.% viscosity regulator and 10 wt.% foam stabilizer in a mechanical ball mill for 4h, setting the ball-milling rotation speed at 380rpm, keeping the mixture at the pressure of 25MPa for 40s, and then keeping the temperature of the pressed sample at 1160 ℃ for 50min to obtain the foamed microcrystalline glass with the porosity of 50% and the compressive strength of 14.12 MPa.

Example 14

And (3) ball-milling 29 wt.% secondary aluminous ash, 34 wt.% waste glass, 30 wt.% viscosity regulator and 7 wt.% foam stabilizer in a mechanical ball mill for 3h, setting the ball-milling rotation speed at 450rpm, keeping the mixture at the pressure of 22MPa for 23s, and then keeping the temperature of the pressed sample at 1200 ℃ for 25min to obtain the foamed microcrystalline glass with the porosity of 72.1% and the compressive strength of 7.25 MPa.

Example 15

Ball-milling 36 wt.% secondary aluminous ash, 40 wt.% waste glass, 18 wt.% viscosity regulator and 6 wt.% foam stabilizer in a mechanical ball mill for 2.7h, setting the ball-milling rotation speed at 420rpm, keeping the mixture at a pressure of 21MPa for 36s, and then keeping the temperature of the pressed sample at 1210 ℃ for 25min to obtain the foamed microcrystalline glass with the porosity of 73% and the compressive strength of 7.11 MPa.

While several embodiments of the present invention have been illustrated and described herein, it will be appreciated by those skilled in the art that changes can be made to the embodiments described herein without departing from the spirit of the invention. The above examples are merely illustrative and should not be taken as limiting the scope of the invention.