Building gel material prepared by modifying incineration fly ash with micro-nano material

Abstract

The invention relates to a building gel material prepared from incineration fly ash modified by a micro-nano material. The building gel material is prepared from 10-20 parts of silicon dioxide-based composite aerogel and 75-120 parts of Portland cement, wherein the silicon dioxide-based composite aerogel is prepared from 10 to 15 parts of incineration fly ash and 10 to 30 parts of silicon dioxide aerogel. Existing industrial waste incineration fly ash and industrial water glass are recycled and then utilized, the water glass is dissolved through acid and then mixed with the incineration fly ash, then aerogel is prepared and formed, and due to the fact that the aerogel naturally has micro-nano mesopores, the incineration fly ash can be well attached and adsorbed, and the utilization rate of the aerogel is increased. The incineration fly ash can be firmly adsorbed and fixed on the water glass; and the gel has a certain adhesion effect, so that the bonding firmness of the incineration fly ash is high, and dissociation and dispersion of the incineration fly ash are avoided. And the formed aerogel and the traditional Portland cement can be used for building materials, so that the resource recycling effect is improved.

Description

Technical Field

[0001] The invention relates to a waste recycling building material, in particular to a building gel material prepared by modifying incineration fly ash with micro-nano materials. Background Art

[0002] Incineration fly ash refers to the fine solid particles produced during the incineration process of garbage, mainly due to the non-combustible materials left over from the incineration process. With the development of garbage incineration technology, the treatment and utilization of incineration fly ash have received more and more attention. This kind of incineration fly ash has the following properties: it contains a variety of heavy metals (such as lead, cadmium, mercury, etc.), salts, residual organic matter and inorganic minerals; High toxicity: Because it may contain harmful substances, improper treatment of incineration fly ash will have a negative impact on the environment and human health; Physical properties: Incineration fly ash is light and fine, and is easily blown away by the wind.

[0003] Industrial water glass, scientifically known as sodium silicate, is an inorganic compound that usually exists in the form of a transparent or translucent liquid. Its main characteristics are as follows: Solubility: Water glass is easily soluble in water to form a viscous liquid. Adhesion: It has good adhesion and can be used as an adhesive. Chemical resistance: It has strong resistance to certain chemicals. High temperature resistance: After heat treatment, water glass can form a high temperature resistant structure.

[0004] The above two substances are very common industrial waste materials in industrial production. If these industrial waste materials are directly disposed of, it is easy to cause waste of resources and environmental damage. The existing technology is also trying to use incineration fly ash as a renewable resource for building material processing. For example, a method and application of preparing cementitious materials using washed garbage incineration fly ash is disclosed in a Chinese invention patent with application number 202110837900.1. However, the freeness of incineration fly ash in this technology is still relatively strong, and it has not formed a relatively strong solidification treatment. Due to its light weight and fineness, it is still easy to precipitate this substance during use; this can easily cause harm during use. Summary of the invention

[0005] The main purpose of the present invention is to provide a technology for recycling water glass and incineration fly ash and solidifying the incineration fly ash.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a building gel material prepared by modifying incineration fly ash using micro-nano materials, which includes 10 to 20 parts of silica-based composite aerogel and 75 to 120 parts of silicate cement; wherein the silica-based composite aerogel includes 10 to 15 parts of incineration fly ash and 10 to 30 parts of silica aerogel.

[0007] Preferably, the silica-based composite aerogel is prepared by mixing water glass with incineration fly ash.

[0008] Preferably, the mesopores of the silica aerogel are in the range of 80 nm to 150 nm.

[0009] Preferably, water glass is dissolved by strong acid and then mixed with incineration fly ash to prepare aerogel.

[0010] The present invention utilizes micro-nano materials to modify incineration fly ash to prepare building gel material, and the preparation process is as follows:

[0011] Industrial water glass is a mixture of silicon source and water, and hydrofluoric acid is added to dissolve it;

[0012] Then add nitric acid solution to adjust the pH to 1-3 to form a solution; add incineration fly ash and mix;

[0013] Then it is adjusted to neutral or alkaline by alkaline solution to form gel again;

[0014] The gel is placed in a mixed solvent of water and ethanol for 3 to 5 days;

[0015] After drying, aerogel is formed, and the aerogel is cut and crushed to form aerogel particles;

[0016] Aerogel particles are mixed with Portland cement to form a building gel material.

[0017] The construction gel material is prepared by modifying incineration fly ash with micro-nano materials, and the preparation process is as follows: 10 parts of industrial water glass and 10 to 50 parts of water are used; the volume ratio of water to ethanol is 1:2 to 1:3.

[0018] The beneficial effects of the present invention are as follows: on the one hand, the existing industrial waste incineration fly ash and industrial water glass are recycled and then utilized. The water glass is dissolved by acid and then mixed with the incineration fly ash to prepare aerogel. Since the aerogel naturally has micro-nano mesopores, it can well adhere to and adsorb the incineration fly ash, so that the incineration fly ash can be firmly adsorbed and fixed on the water glass; and the gel itself has a certain adhesion effect, so it has a strong bonding strength to the incineration fly ash, avoiding the free and dispersion of the incineration fly ash. The formed aerogel and traditional silicate cement can then be used as building materials, improving the effect of resource recycling and reuse. And after experimental analysis, the strength and safety of the recycled building gel material meet the standards. DETAILED DESCRIPTION

[0019] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0020] The present invention utilizes micro-nano materials to modify incineration fly ash to prepare building gel material, and the preparation process is as follows:

[0021] Industrial water glass is the silicon source, mixed with water, and hydrofluoric acid is added to dissolve;

[0022] Then add nitric acid solution to adjust the pH to 1-3 to form a solution; add incineration fly ash and mix;

[0023] Then, the solution is adjusted to neutral or alkaline to form a gel again; the alkaline solution is, for example, sodium hydroxide or potassium hydroxide, and the amount used is adjusted to neutral or pH 7-8.

[0024] The gel is placed in a mixed solvent of water and ethanol for 3 to 5 days;

[0025] After drying, aerogel is formed, and the aerogel is cut and crushed to form aerogel particles;

[0026] Aerogel particles are mixed with Portland cement to form a building gel material.

[0027] The incineration fly ash is modified by micro-nano materials to prepare a building gel material, and the preparation process is as follows: industrial water glass is used as a silicon source and mixed with water in a weight ratio of 1:1 to 1:5; the volume ratio of water and ethanol in the mixed solvent is 1:1 to 1:2.

[0028] Table 1, Examples 1 to 5 in the following table give specific examples of several ratios. The volume ratio of hydrofluoric acid L to water glass KG is 1:10 to 1:1. The amount of nitric acid is adjusted to the required pH. The amount of mixed solvent water and ethanol is based on submerging the covering gel. The water glass comes from Shandong Tianhong Chemical Company.

[0029] Example Water glass KG Water KG Hydrofluoric acid L Incineration fly ash KG Portland cement KG Example 1 5 10 2 10 90 Example 2 7 15 2 10 90 Example 3 9 10 2 10 90 Example 4 10 10 3 10 90 Example 5 12 10 3 10 90

[0030] Experimental Example 1, Table 2 below shows the density, specific surface area and mesopore size obtained after parameter testing of aerogels in different embodiments. As can be seen from the table below, as the amount of water glass used increases, the overall density decreases, the surface area increases, and the average pore size decreases; the surface area increases, while the average pore size decreases, which better adsorbs, adheres and fixes the incineration fly ash.

[0031] Example <![CDATA[Density g / cm 3 > <![CDATA[Specific surface area m 2 / g]]> Average pore size nm Example 1 0.65 220 78 Example 2 0.61 213 82 Example 3 0.55 235 58 Example 4 0.51 243 53 Example 5 0.50 246 48

[0032] Experimental Example 2: The prepared building gel material is used to obtain building materials, and the building materials are immersed in water. After 72 hours, the metal ions precipitated into the water are detected to obtain the following Table 3. It can be seen from Table 3 that the levels of these heavy metal ions are low or not detected, which meets the requirements of the specifications.

[0033] Example Cr(mg / L) Cd(mg / L) Hg(mg / L) Pb(mg / L) Example 1 0.02 0 0.01 0 Example 2 0.01 0 0.01 0

[0034] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. A method for preparing a building gel material by modifying incineration fly ash with micro-nano materials, characterized in that: The invention comprises 10 to 20 parts of silica-based composite aerogel and 75 to 120 parts of silicate cement; wherein the silica-based composite aerogel comprises 10 to 15 parts of incineration fly ash and 10 to 30 parts of silica aerogel.

2. The method for preparing building gel material by modifying incineration fly ash with micro-nano materials according to claim 1, characterized in that: Silica-based composite aerogels are prepared by mixing water glass with incineration fly ash.

3. The method for preparing building gel material by modifying incineration fly ash with micro-nano materials according to claim 1, characterized in that: The mesopores of silica aerogel are 80 to 150 nm.

4. The method for preparing building gel material by modifying incineration fly ash with micro-nano materials according to claim 1, characterized in that: The water glass is dissolved by strong acid and mixed with incineration fly ash to prepare aerogel.

5. The method for preparing building gel material by modifying incineration fly ash with micro-nano materials according to claim 1, characterized in that: The preparation process is as follows: Industrial water glass is the silicon source, mixed with water, and hydrofluoric acid is added to dissolve; Then add nitric acid solution to adjust the pH to 1-3 to form a solution; add incineration fly ash and mix; Then it is adjusted to neutral or alkaline by alkaline solution to form gel again; The gel is placed in a mixed solvent of water and ethanol for 3 to 5 days; After drying, aerogel is formed, and the aerogel is cut and crushed to form aerogel particles; Aerogel particles are mixed with Portland cement to form a building gel material.

6. The method for preparing building gel material by modifying incineration fly ash with micro-nano materials according to claim 5, characterized in that: The preparation process is as follows: the weight ratio of industrial water glass to water is 1:1 to 1:5; the volume ratio of the mixed solvent water and ethanol is 1:2 to 1:3.