阅读说明：本技术 一种微孔发泡玻璃的制备方法 (Preparation method of microporous foamed glass ) 是由 王冰星 彭丽芬 柳雷 于 2021-01-27 设计创作，主要内容包括：本发明公开了一种微孔发泡玻璃的制备方法,微孔发泡玻璃的原材料组份质量之和按100％计算时各组分的含量为：废玻璃62.8～76.5％,钠长石7.3～16.8％,发泡剂5.0～12.0％,助溶剂4.4～18.6％,发泡剂为空心玻璃微珠与硝酸钠或空心玻璃微珠与硝酸钠、碳酸钙的混合物,助溶剂为硼砂、硼酸、萤石的混合物。先制备坯料,坯料在高温炉内以5～8℃/min升温至780～860℃,保温30～50min,然后随炉冷却,制得微孔发泡玻璃。本发明采用空心玻璃微珠作为物理发泡剂,有效避免了发泡过程中异常孔洞的产生,制备的微孔发泡玻璃闭气孔率≥90％且孔径<1mm,显著提升了材料的抗压强度和保温隔热性能。(The invention discloses a preparation method of microporous foamed glass, wherein the mass sum of the raw material components of the microporous foamed glass is 100%, and the content of each component is as follows: 62.8-76.5% of waste glass, 7.3-16.8% of albite, 5.0-12.0% of foaming agent and 4.4-18.6% of cosolvent, wherein the foaming agent is a mixture of hollow glass beads and sodium nitrate or hollow glass beads, sodium nitrate and calcium carbonate, and the cosolvent is a mixture of borax, boric acid and fluorite. Firstly, preparing a blank, heating the blank to 780-860 ℃ at a speed of 5-8 ℃/min in a high-temperature furnace, preserving heat for 30-50 min, and then cooling along with the furnace to obtain the microporous foamed glass. According to the invention, the hollow glass beads are used as a physical foaming agent, so that abnormal holes are effectively avoided in the foaming process, the closed porosity of the prepared microporous foamed glass is more than or equal to 90%, the pore diameter is less than 1mm, and the compressive strength and the heat-insulating property of the material are obviously improved.)

1. A preparation method of microporous foamed glass is characterized in that the content of each component is as follows when the sum of the raw material components is calculated according to 100 percent: 62.8-76.5% of waste glass, 7.3-16.8% of albite, 5.0-12.0% of foaming agent and 4.4-18.6% of cosolvent; the foaming agent is a mixture of hollow glass beads and sodium nitrate or hollow glass beads, sodium nitrate and calcium carbonate; the cosolvent is a mixture of borax, boric acid and fluorite.

2. A method for preparing microcellular foam glass according to claim 1, wherein the contents of the components are as follows: 68.5-71.3% of waste glass, 8.6-15.1% of albite, 8.0-12.0% of foaming agent and 7.3-11.2% of cosolvent.

3. A method for producing a cellular foamed glass according to claim 1 or 2, characterized in that the foaming agent comprises the following material components in mass: 96.9-98.5% of hollow glass beads, 1.5-2.5% of sodium nitrate and 0-1.6% of calcium carbonate, wherein the sum of the mass of the materials is 100%.

4. A method for preparing microcellular foam glass according to claim 3, wherein said cosolvent comprises the following material components by mass: 13.0-23.0% of borax, 70.0-81.5% of boric acid and 5.5-9.0% of fluorite, wherein the sum of the mass of the materials is 100%.

5. A method for preparing microcellular foamed glass according to claim 4, wherein said foaming agent comprises the following material components in mass percent: 96.9-98.2% of hollow glass beads, 1.5-2.4% of sodium nitrate and 0.3-1.6% of calcium carbonate; what is needed isThe vacuum density of the hollow glass beads is 0.15-0.18 g/cm³The particle size is 10 to 85 μm.

6. A method for preparing microcellular foam glass according to claim 5, which is prepared by the following process:

(1) preparing a blank: putting waste glass, albite, cosolvent, sodium nitrate, calcium carbonate and water into a ball mill for ball milling to obtain uniformly mixed slurry, dehydrating and drying, scattering the dried material to obtain a mixture, putting the mixture, hollow glass beads and a binder accounting for 3.5-6.7% of the total mass of the raw materials into a stirring tank, and mixing to obtain a blank;

(2) high-temperature foaming: and (2) filling the blank prepared in the step (1) into a mold paved with ceramic fiber paper for compression molding, heating to 780-860 ℃ at a speed of 5-8 ℃/min in a high-temperature furnace, preserving heat for 30-50 min, and then cooling along with the furnace to obtain the microporous foamed glass.

7. The method of claim 6, wherein the step of preparing the microcellular foam glass comprises: the ball milling takes zirconia balls as a grinding medium, wherein the mass ratio of grinding balls to raw materials to water is (2.3-2.9): 1: (0.35-0.4).

8. A method of producing microcellular foamed glass according to claim 7, wherein: the scattering adopts an airflow crusher, and the particle size of the mixture prepared after scattering is less than or equal to 100 mu m.

9. A method for producing microcellular foam glass according to claim 8, wherein said binder comprises the following material components in mass: 1.1-1.5% of beta-cyclodextrin, 3.3-4.1% of glycerol, 3.4-4.3% of sodium polymethylcellulose, 1.4-1.8% of polyethylene glycol and 88.3-90.8% of water, wherein the sum of the mass of the above materials is 100%.

10. A method for producing microcellular foam glass according to claim 9, wherein said binder comprises the following material components in mass: 1.3% of beta-cyclodextrin, 3.7% of glycerol, 3.8% of sodium polymethylcellulose, 1.6% of polyethylene glycol and 89.6% of water.

Technical Field

The invention belongs to the technical field of foamed glass preparation, and particularly relates to a preparation method of microporous foamed glass, which can be widely applied to the fields of chemical industry, environmental protection, buildings, underground engineering, national defense war industry and the like, and is particularly suitable for fireproof engineering, waterproof engineering, building heat preservation and energy conservation and the like.

Background

The foam glass is foam glass for sealing air holes, has the excellent characteristics of small heat conductivity coefficient, low volume weight, high compressive strength, low water absorption, corrosion resistance, good chemical stability and the like, can be widely applied to the fields of chemical engineering, environmental protection, buildings, underground engineering, military products and the like to achieve the effects of water prevention, heat insulation, heat preservation, sound insulation and the like, and is called as an environment-friendly heat-insulating material.

Currently, the foaming agents used for preparing foamed glass are divided into two main categories according to the different foaming principles: one is a decomposition type foaming agent which generates gas such as carbonate, nitrate, sulfate, manganese dioxide and the like through decomposition reaction under the high-temperature condition; one is an oxidative blowing agent which undergoes an oxidation reaction with an oxygen-containing component to produce a gas, such as carbon black, sodium nitrate, and the like. In the high-temperature foaming process of the foamed glass, due to the problems of matching of the mixing amount, granularity, distribution and the like of the foaming agent with a thermal regulation, liquid phase viscosity, surface tension and the like, the product often has the defects of uneven structure of communicating holes and foam holes, large pore diameter difference and the like, and the defects can not be eliminated, so that the water absorption rate and the heat conductivity coefficient of the product are increased, the heat preservation and insulation effect is influenced, and the yield of the product is directly low. Therefore, the non-uniform pore diameter and abnormal holes of the foamed glass are the problems to be solved at present.

Disclosure of Invention

The invention aims to provide a preparation method of microporous foamed glass, aiming at the defects of low strength, high water absorption and high heat conductivity coefficient caused by the defects of large and uneven pore diameter, abnormal pores and the like of the foamed glass in the prior art.

In order to achieve the above object, the present invention provides a method for preparing microcellular foam glass, wherein the contents of the raw material components are as follows when the sum of the raw material components is calculated according to 100%: 62.8-76.5% of waste glass, 7.3-16.8% of albite, 5.0-12.0% of foaming agent and 4.4-18.6% of cosolvent; the foaming agent is a mixture of hollow glass beads and sodium nitrate or hollow glass beads, sodium nitrate and calcium carbonate; the cosolvent is a mixture of borax, boric acid and fluorite.

The invention relates to a preparation method of microporous foamed glass, which preferably comprises the following components in percentage by weight: 68.5-71.3% of waste glass, 8.6-15.1% of albite, 8.0-12.0% of foaming agent and 7.3-11.2% of cosolvent.

The foaming agent comprises the following material components in percentage by mass: 96.9-98.5% of hollow glass beads, 1.5-2.5% of sodium nitrate and 0-1.6% of calcium carbonate, wherein the sum of the mass of the materials is 100%; the foaming agent comprises the following material components in percentage by mass: 96.9-98.2% of hollow glass microspheres, 1.5-2.4% of sodium nitrate and 0.3-1.6% of calcium carbonate.

The cosolvent comprises the following material components in percentage by mass: 13.0-23.0% of borax, 70.0-81.5% of boric acid and 5.5-9.0% of fluorite, wherein the sum of the mass of the materials is 100%.

The parameters of the hollow glass bead adopted by the invention are preferably as follows: the true density is 0.15-0.18 g/cm³The particle size is 10 to 85 μm.

The invention relates to a preparation method of microporous foamed glass, which adopts the following process:

(1) preparing a blank: putting waste glass, albite, a cosolvent, sodium nitrate, calcium carbonate and water into a ball mill for ball milling to obtain uniformly mixed slurry, dehydrating and drying, scattering the dried material to obtain a mixture, putting the mixture, hollow glass beads and a binder accounting for 3.5-6.7% of the total mass of the raw materials into a stirring tank, and mixing to obtain a blank;

(2) high-temperature foaming: and (2) filling the blank prepared in the step (1) into a mold paved with ceramic fiber paper for compression molding, heating to 780-860 ℃ at a speed of 5-8 ℃/min in a high-temperature furnace, preserving heat for 30-50 min, and then cooling along with the furnace to obtain the microporous foamed glass.

In order to prevent the mixing of impurities, zirconia balls are used as grinding media, namely grinding balls, in the ball milling process; in order to improve the grinding efficiency, the mass ratio of the grinding beads to the raw materials to the water is (2.3-2.9): 1: (0.35-0.4).

The breaking up is preferably carried out by adopting an airflow crusher, and the grain diameter of the mixture prepared after the breaking up is preferably less than or equal to 100 mu m.

The binder comprises the following material components in percentage by mass: 1.1-1.5% of beta-cyclodextrin, 3.3-4.1% of glycerol, 3.4-4.3% of sodium polymethylcellulose, 1.4-1.8% of polyethylene glycol and 88.3-90.8% of water, wherein the sum of the mass of the above materials is 100%; the optimal mixture ratio is as follows: 1.3% of beta-cyclodextrin, 3.7% of glycerol, 3.8% of sodium polymethylcellulose, 1.6% of polyethylene glycol and 89.6% of water.

By optimizing the technical scheme, the volume weight of the prepared microporous foamed glass is 180-230 kg/m³The heat conductivity coefficient is 0.053-0.062W/(m.k), the volume water absorption is less than or equal to 0.43%, the closed pore rate is more than or equal to 90%, and the pore diameter<0.9mm and the compressive strength of 0.85-1.25 MPa.

Compared with the prior art, the preparation method of the microporous foamed glass has the following beneficial effects:

(1) the microporous foamed glass takes the solid waste glass as a basic raw material, so that the raw material is easy to obtain and low in price, and the ore resource is saved, so that the production cost of the foamed glass is reduced, and the high added value utilization of the waste glass is realized.

(2) According to the microporous foamed glass, the hollow glass beads are used as the physical foaming agent, in the high-temperature foaming process, gas in the hollow glass bead spherical shell is subjected to thermal expansion and is always coated in the spherical shell, so that intercommunicating pores are avoided, the cell structure is regular, the closed cell rate is improved, stress concentration is effectively avoided, and the strength of the microporous foamed glass is improved.

(3) The invention adopts the hollow glass beads as spherical micron-sized hollow particles, thereby hindering heat convection, prolonging the heat conduction path, having the efficient reflection function of the cell wall curve to the heat radiation and the like, and obviously reducing the heat conductivity coefficient of the microporous foam glass.

(4) The invention introduces trace chemical foaming agent, preferably sodium nitrate and calcium carbonate, adjusts the volume weight of the microporous foaming glass, and finally prepares the high-efficiency heat-preservation fireproof foaming glass with high closed porosity, low heat conductivity coefficient, low water absorption rate and micron-order pores.

Detailed Description

To describe the present invention, the following will explain the preparation method of a microcellular foamed glass of the present invention in detail with reference to the examples. The invention is not limited to the examples.

Example 1

The foaming glass comprises the following raw materials in percentage by mass: 71.3% of waste glass, 8.6% of albite, 10.29% of hollow glass beads, 0.21% of sodium nitrate, 1.54% of borax, 7.2% of boric acid and 0.86% of fluorite. Wherein the vacuum density of the hollow glass beads is 0.15g/cm³。

(1) Weighing waste glass, albite, sodium nitrate, borax, boric acid and fluorite according to a ratio, putting zirconium oxide grinding beads, raw materials and water into a ball milling tank according to a mass ratio of 2.6:1:0.35, and grinding for 60min to obtain uniform slurry; placing the slurry in a forced air drying oven, and drying at 110 deg.C for 100 min; and (3) scattering the dried material by using an airflow crusher, and then placing the scattered material, the hollow glass beads and a binder accounting for 5% of the total mass of the raw materials in a stirring tank for mixing for 25min to obtain a blank.

(2) And putting the prepared blank into a refractory material grinding tool paved with ceramic fiber paper, pressing and forming, putting into a high-temperature furnace, heating from room temperature to a foaming temperature of 800 ℃ at a heating rate of 5 ℃/min, preserving heat for 40min, cooling along with the furnace, demolding and cutting to obtain the microporous foamed glass.

Example 2

The foaming glass comprises the following raw materials in percentage by mass: 68.5 percent of waste glass and 1 percent of albite5.1 percent, 11.76 percent of hollow glass beads, 0.18 percent of sodium nitrate, 0.06 percent of calcium carbonate, 0.66 percent of borax, 3.45 percent of boric acid and 0.29 percent of fluorite. Wherein the hollow glass micro-bead has a true density of 0.18g/cm³。

(1) Weighing waste glass, albite, sodium nitrate, calcium carbonate, borax, boric acid and fluorite according to the proportion, putting zirconium oxide grinding beads, raw materials and water into a ball milling tank according to the mass ratio of 2.3:1:0.4, and grinding for 110min to prepare uniform slurry; placing the slurry in a forced air drying oven, and drying at 110 deg.C for 130 min; and scattering the dried material by using an airflow crusher, and then placing the scattered material, the hollow glass beads and a binder accounting for 4.7 percent of the total mass of the raw materials in a stirring tank for mixing for 30min to obtain a blank.

(2) And putting the prepared blank into a refractory material grinding tool paved with ceramic fiber paper, pressing and forming, putting into a high-temperature furnace, heating from room temperature to a foaming temperature of 860 ℃ at a heating rate of 7 ℃/min, preserving heat for 30min, cooling along with the furnace, demolding, and cutting to obtain the foamed glass.

Example 3

The foaming glass comprises the following raw materials in percentage by mass: 76.5 percent of waste glass, 7.3 percent of albite, 4.86 percent of hollow glass beads, 0.11 percent of sodium nitrate, 0.03 percent of calcium carbonate, 2.01 percent of borax, 8.28 percent of boric acid and 0.91 percent of fluorite. Wherein the vacuum density of the hollow glass beads is 0.15g/cm³。

(1) Weighing waste glass, albite, sodium nitrate, calcium carbonate borax, boric acid and fluorite according to a ratio, putting zirconium oxide grinding beads, raw materials and water into a ball milling tank according to a mass ratio of 2.5:1:0.4, and grinding for 90min to prepare uniformly ground slurry; placing the slurry in a forced air drying oven, and drying at 110 deg.C for 100 min; and (3) scattering the dried material by using an airflow crusher, and then placing the scattered material, the hollow glass beads and a binder accounting for 6.2% of the total mass of the raw materials in a stirring tank for mixing for 30min to obtain a blank.

(2) And putting the prepared blank into a refractory material grinding tool paved with ceramic fiber paper, pressing and forming, putting into a high-temperature furnace, heating from room temperature to foaming temperature of 780 ℃ at the heating rate of 6 ℃/min, preserving heat for 50min, cooling along with the furnace, demoulding and cutting to obtain the foamed glass.

In the above embodiment, the adopted binder comprises the following material components in percentage by mass: 1.3% of beta-cyclodextrin, 3.7% of glycerol, 3.8% of sodium polymethylcellulose, 1.6% of polyethylene glycol and 89.6% of water.

The upper and lower limit values and interval values of the raw materials, additives and process parameters related to the invention can all realize the invention, and are not listed.

The performance test method of the microporous foamed glass prepared in the embodiment is as follows: the test method of the compressive strength and the volume water absorption refers to JC/T647-2014 foam glass heat insulation products; the heat conductivity coefficient test method refers to GB/T10294-2008 heat insulation material steady-state thermal resistance and related characteristic determination-protective hot plate method; the volume weight and closed cell fraction are calculated by the following formula:

1) volume weight D_b：

2) Apparent porosity Pa:

3) true porosity Pt:

4) closed cell ratio Pc: p_c＝P_t-P_a

In the formula D₁Density (g/cm) of the test solution at temperature³)；D_tTrue density (g/cm) of the sample³)；M₁-sample mass (g), oven-dried at 110 ℃ to constant weight; m₂Placing the sample in a beaker or other clean container, slowly injecting soaking liquid (distilled water) until the sample is immersed, standing in air for 30min, placing the saturated sample on a lifting hook of a balance, and weighing the mass; m₃The weight (g) of the sample is immediately weighed by using a towel saturated with immersion liquid to remove the liquid beads hanging on the surface of the saturated sample.

TABLE 1 Performance of microcellular foamed glass prepared in examples 1-3.