阅读说明：本技术 含大量垃圾焚烧飞灰和矿渣的胶凝材料及制备方法和应用 (Cementing material containing a large amount of waste incineration fly ash and slag, and preparation method and application thereof ) 是由 倪文 张思奇 王珂 李佳 王一杰 王莹 史腾宇 于 2019-10-28 设计创作，主要内容包括：本发明涉及一种含大量垃圾焚烧飞灰和矿渣的胶凝材料及其制备方法和应用。一种含大量垃圾焚烧飞灰和矿渣的胶凝材料,主要由以下成分组成：按重量份计,S95矿渣30-70份,垃圾焚烧飞灰20-60份,脱硫石膏7～13份。本发明掺杂了大量的垃圾焚烧飞灰,并且无需添加激发剂、早强剂等外加剂即可显示出良好的可工业应用的抗压强度,既可用作混凝土的胶结料,又可用于采矿胶结充填料,是水泥的良好替代品。(The invention relates to a cementing material containing a large amount of waste incineration fly ash and slag, and a preparation method and application thereof. A cementing material containing a large amount of waste incineration fly ash and slag mainly comprises the following components: 30-70 parts of S95 slag, 20-60 parts of waste incineration fly ash and 7-13 parts of desulfurized gypsum. The invention is doped with a large amount of waste incineration fly ash, can show good compression strength capable of being industrially applied without adding additives such as excitant, early strength agent and the like, can be used as cementing material of concrete and cementing filling material for mining, and is a good substitute of cement.)

1. A cementing material containing a large amount of waste incineration fly ash and slag is characterized by mainly comprising the following components:

30-70 parts of S95 slag, 20-60 parts of waste incineration fly ash and 7-13 parts of desulfurized gypsum.

2. Cement according to claim 1, characterized by consisting of: 30-70 parts of S95 slag, 20-60 parts of waste incineration fly ash and 9-11 parts of desulfurized gypsum;

preferably, 30-70 parts of S95 slag, 20-40 parts of waste incineration fly ash and 10 parts of desulfurized gypsum by weight.

3. The cementitious material of claim 1, wherein the waste incineration fly ash consists essentially of: 32-42 parts of CaO, 12-28 parts of Cl and SiO by weight₂2-6 parts of Al₂O₃1-4 parts, K₂3-7 parts of O, 3-7 parts of MgO and Na₂O3-7 parts, Fe₂O₃1-3 parts.

4. Cement according to claim 1, characterised in that the S95 slag consists essentially of: 45-50 parts of CaO and SiO by weight₂28-32 parts of Al₂O₃10-14 parts of MgO 5-7 parts of Fe₂O₃1-2 parts of SO₃0-1 part.

5. Cement according to claim 1, characterised in that the desulfurized gypsum consists essentially of: 45-50 parts of CaO and SiO by weight₂2-3 parts of Al₂O₃0-1 part of MgO, 1-2 parts of SO₃40-46 parts of Cl and 0-1 part of Cl.

6. Cement according to claim 1, characterised in that the specific surface area of the S95 slag is 500m²More than kg;

preferably, the specific surface area of the desulfurized gypsum is 400m²More than kg.

7. A method for preparing a cementitious material as claimed in any one of claims 1 to 6, characterised in that it comprises the following steps:

and uniformly mixing all the raw materials with water according to the water-to-glue ratio of 0.3-0.5: 1.

8. The method according to claim 7, wherein the waste incineration fly ash is produced by a grate furnace incineration technique.

9. Use of the cementitious material according to any one of claims 1 to 6 for making concrete or mining fillers.

10. Concrete, characterized in that it comprises a cementitious material according to any one of claims 1 to 6 and in that the water-to-cement ratio of the concrete is 0.2 to 0.4: 1.

Technical Field

The invention relates to the field of building materials, in particular to a cementing material containing a large amount of waste incineration fly ash and slag, and a preparation method and application thereof.

Background

According to statistics of research institute of E20, 257 operating waste incineration power plants are built nationwide in 2015, the total quantity of waste incineration in China is 6811 ten thousand tons, and according to national records of hazardous wastes, fly ash (hereinafter, fly ash) generated in the waste incineration process belongs to hazardous wastes and is about 3% -5% of the quantity of incineration waste, the generation quantity of the fly ash reaches 395 ten thousand tons, nearly 300 waste incineration power plants are built in 2016 years, and the fly ash reaches over 1000 ten thousand tons per year after 2020. In the face of such huge annual output of waste incineration fly ash, the search for a reasonable green disposal method is urgent, and how to maximize the utilization of the hazardous waste such as fly ash becomes a hot content of the research in the hazardous waste disposal field of the present time. The slag and the desulfurized gypsum are utilized to prepare the full-solid waste cementing material by utilizing the waste incineration fly ash in a synergistic manner, so that the problems of reduction, harmlessness and resource utilization of industrial solid waste (steel slag) and urban hazardous waste (waste incineration fly ash) can be solved, the synergistic utilization of the solid waste and the hazardous waste and environmental protection are promoted, the cementing material is provided for large-scale replacement of cement solidification stabilization safety landfill or preliminary combination of a cementing filling mining technology, and the engineering application foundation is laid. However, the existing cementing material containing waste incineration fly ash has the following problems: the strength with practical value can be achieved only by adding excessive additives such as excitant, early strength agent and the like.

Disclosure of Invention

The invention aims to provide a cementing material containing a large amount of waste incineration fly ash and slag, which is doped with a large amount of waste incineration fly ash, can show good compression strength capable of being industrially applied without adding additives such as an excitant, an early strength agent and the like, can be used as a cementing material of concrete, can be used as a mining filling material and is a good substitute of cement.

In order to achieve the above purpose, the invention provides the following technical scheme:

a cementing material containing a large amount of waste incineration fly ash and slag mainly comprises the following components:

30-70 parts of S95 slag, 20-60 parts of waste incineration fly ash and 7-13 parts of desulfurized gypsum.

The cementing material has at least the following characteristics:

firstly, compared with the existing cementing material containing a large amount of waste incineration fly ash and slag, the cementing material disclosed by the invention is simpler in composition, does not need to add additives such as an exciting agent and an early strength agent, and consists of three components of S95 slag, waste incineration fly ash and desulfurized gypsum, so that the raw material cost is greatly reduced, and the utilization rate of the waste incineration fly ash is higher.

Second, the composition is simplified while still exhibiting good cementitious properties, including compressive strength and effective solidification of various heavy metals in the fly ash. The water-cement ratio is 0.3:1, and the cementing material is prepared into a pure slurry test block according to GB17671-1999 cement mortar strength test method, the test block size is 30mm multiplied by 50mm, and the curing is carried out at the temperature of 35 ℃ and the humidity of more than 99.5 percent, so that the high-strength fly ash cement mortar has good compressive strength and can effectively cure a plurality of heavy metals in fly ash.

Thirdly, the safety is high: the adopted waste incineration fly ash has good safety, and the leaching concentration of heavy metal ions (Cr, Cu, Zn, Cd, Sb, Hg, Pb and the like) is all lower than the drinking water standard for a long time (360 d); in addition, the slag and the desulfurized gypsum have certain solidification effect on chloride ions in the fly ash, and the corrosion to other building materials such as reinforcing steel bars is avoided.

In conclusion, the cementing material provided by the invention utilizes slag to replace the traditional cementing agent cement, and synergistically utilizes the waste incineration fly ash to prepare the full-solid waste cementing material, so that the waste incineration fly ash is recycled to the maximum extent, a better mixing amount of the waste incineration fly ash in a full-solid waste cementing system is provided, and the leaching concentration of heavy metal ions in the system is still lower than the drinking water standard in short-term and long-term leaching toxicity (horizontal oscillation method), so that the problems of reduction, harmlessness and recycling of industrial solid waste (steel slag) and urban hazardous waste (waste incineration fly ash) can be solved, the synergistic utilization of the solid waste and the hazardous waste and environmental protection are promoted, the cementing material is provided for large-scale replacement of cement solidification stabilization safe landfill, preliminary bonding filling mining technology or preparation of concrete for buildings, and an engineering application foundation is laid.

The S95 slag according to the present invention refers to any slag having a 28d reactivity index of not less than 95%.

The waste incineration fly ash refers to bottom ash generated in the incineration disposal process of domestic waste or industrial waste, and is the waste incineration fly ash of a mechanical grate incineration process.

The main component of the desulfurized gypsum of the invention is similar to natural gypsum and is calcium sulfate dihydrate CaSO₄·2H₂O。

The invention also optimizes the proportion and the chemical composition of each component on the basis of the formula so as to improve the gelling property to a greater extent or reduce the industrial cost.

Preferably, the cement containing a large amount of waste incineration fly ash and slag consists of only S95 slag, waste incineration fly ash and desulfurized gypsum, and as described above, each component may take any value within the above range. For example, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, etc. may be taken as the refuse-incinerated fly ash. The S95 slag may be taken in 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, etc. The desulfurized gypsum may be taken in amounts of 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts and 13 parts.

Preferably, the cement material containing a large amount of waste incineration fly ash and slag consists essentially of:

30-70 parts of S95 slag, 20-60 parts of high-safety-rate-dump garbage incineration fly ash and 7-13 parts of desulfurized gypsum.

Preferably, the cement material containing a large amount of waste incineration fly ash and slag consists essentially of:

30-70 parts of S95 slag, 20-60 parts of Lujiashan waste incineration fly ash and 9-11 parts of desulfurized gypsum.

Preferably, the cement material containing a large amount of waste incineration fly ash and slag consists essentially of:

30-70 parts of S95 slag, 20-60 parts of waste incineration fly ash of Sichuan plants and 10 parts of desulfurized gypsum.

Preferably, the cement material containing a large amount of waste incineration fly ash and slag consists essentially of:

30-70 parts of S95 slag, 20-60 parts of fly ash from waste incineration in certain plants in North Hu China and 10 parts of desulfurized gypsum.

Preferably, the waste incineration fly ash mainly consists of the following components: 32-42 parts of CaO, 12-28 parts of Cl and SiO by weight₂2-6 parts of Al₂O₃1-4 parts, K₂3-7 parts of O, 3-7 parts of MgO and Na₂O3-7 parts, Fe₂O₃1-3 parts.

Preferably, the S95 slag consists essentially of: 45-50 parts of CaO and SiO by weight₂28-32 parts of Al₂O₃10-14 parts of MgO 5-7 parts of Fe₂O₃1-2 parts of SO₃0-1 part.

Preferably, the desulfurized gypsum consists essentially of: 45-50 parts of CaO and SiO by weight₂2-3 parts of Al₂O₃0-1 part of MgO, 1-2 parts of SO₃40-46 parts of Cl and 0-1 part of Cl.

The chemical compositions of the refuse incineration fly, the S95 slag and the desulfurized gypsum according to the present invention refer to the contents of various metals or mineral elements in terms of oxides, and do not refer to the contents of compounds present in the refuse incineration fly, the S95 slag or the desulfurized gypsum slag in terms of oxides. In addition, the above chemical composition results can be obtained by conventional detection methods known in the art, such as typical fluorescence detection after or without loss of ignition.

When fluorescence detection is performed after ignition loss, the ignition loss temperature is usually about 900. + -. 5 ℃.

Preferably, the S95 slag has a specific surface area of 500m²More than kg.

Preferably, the specific surface area of the desulfurized gypsum is 400m²More than kg.

The specific surface area of the raw materials is improved through grinding, so that the activity of the slag is stimulated, the hydration difficulty is reduced, and the uniformity of the materials is improved.

The S95 slag, waste incineration fly ash and desulfurized gypsum used in the invention can be purchased from the market or prepared by self, as long as the requirements of chemical compositions are met.

At present, the incineration treatment technology in China is mainly divided into three types: grate furnace technology, fluidized bed technology, and other incineration technologies. The waste incineration fly ash generated by the incineration technology comprises two parts, wherein one part is ash obtained by a heat recovery utilization system in front of a flue gas purification system, and comprises (boiler ash, economizer ash and superheater ash), and the other part is flue gas purification system (APC) ash, comprising wet process or semi-dry process dust remover ash, cyclone dust remover ash and bag-type dust remover ash. The fly ash used by the invention adopts a grate furnace incineration technology, and the fly ash produced by incineration through the grate furnace incineration technology contains much higher heavy metal, dioxin and chloride than the fly ash produced by other incineration technologies. However, the fly ash with such great harm is still used to prepare the cementing material, and the lower metal leaching rate is still displayed, which shows that the fly ash has good synergistic effect with slag and gypsum, and the synergistic effect can efficiently solidify heavy metals in the fly ash, thereby reducing the leaching rate and improving the safety of the cementing material.

When the cementing material is used, the cementing material is mixed with water according to the water-cement ratio of 0.3-0.5: 1, and concrete can be prepared by utilizing the water-cement ratio.

In summary, compared with the prior art, the invention achieves the following technical effects:

(1) the recovery rate of the waste incineration fly ash is improved;

(2) the raw material composition of the cementing material containing a large amount of waste incineration fly ash and slag is simplified;

(3) the waste incineration fly ash, the slag and the desulfurized gypsum have synergistic effect to show higher compressive strength and effectively solidify various heavy metals in the fly ash.

(4) The cementing material has high safety and no heavy metal leaching risk;

(5) the preparation method is simple.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.