阅读说明：本技术 一种水泥混合物及其制备方法 (Cement mixture and preparation method thereof ) 是由 张建华 胡春才 于 2019-10-17 设计创作，主要内容包括：本发明公开了一种水泥混合物及其制备方法,按重量份计,水泥混合物包括硅酸盐水泥熟料60-75份、石膏4-10份、石灰石5-10份、矿粉8-15份、钢渣粉10-15份、可再分散乳胶粉2-5份；钢渣原料经粉磨处理获得钢渣粉,粉磨处理期间,加入占钢渣原料重量比为1.3-2.2%的助磨组合添加剂,助磨组合添加剂包括质量比为1:(0.6-1.4)的硼砂和胶体石墨粉。水泥混合物还可包括氢氧化钾2-7份、改性空心玻璃微珠6-12份；采用硅烷偶联剂处理空心玻璃微珠获得改性空心玻璃微珠。水泥混合物的制备包括：制备钢渣粉；制备改性空心玻璃微珠；将水泥混合物的原料组分混合后经水泥粉磨制得水泥混合物。采用本发明的水泥混合物配制的混凝土拌合物的抗压强度高,且实现了钢渣的废物利用。(The invention discloses a cement mixture and a preparation method thereof, wherein the cement mixture comprises, by weight, 60-75 parts of portland cement clinker, 4-10 parts of gypsum, 5-10 parts of limestone, 8-15 parts of mineral powder, 10-15 parts of steel slag powder and 2-5 parts of redispersible latex powder; grinding the steel slag raw material to obtain steel slag powder, and adding a grinding-aid combined additive accounting for 1.3-2.2% of the weight of the steel slag raw material during the grinding treatment, wherein the grinding-aid combined additive comprises borax and colloidal graphite powder in a mass ratio of 1 (0.6-1.4). The cement mixture can also comprise 2-7 parts of potassium hydroxide and 6-12 parts of modified hollow glass beads; and treating the hollow glass beads by adopting a silane coupling agent to obtain the modified hollow glass beads. The preparation of the cement mixture comprises: preparing steel slag powder; preparing modified hollow glass beads; the raw material components of the cement mixture are mixed and ground into the cement mixture. The concrete mixture prepared by the cement mixture has high compressive strength, and realizes the waste utilization of steel slag.)

1. The cement mixture is characterized by comprising the following raw material components in parts by weight: 60-75 parts of silicate cement clinker, 4-10 parts of gypsum, 5-10 parts of limestone, 8-15 parts of mineral powder, 10-15 parts of steel slag powder and 2-5 parts of redispersible latex powder;

the preparation of the steel slag powder comprises the following steps: grinding the steel slag raw material to obtain steel slag powder, and adding a grinding-aid combined additive accounting for 1.3-2.2% of the weight of the steel slag raw material during the grinding treatment, wherein the grinding-aid combined additive comprises borax and colloidal graphite powder, and the mass ratio of the borax to the colloidal graphite powder is 1 (0.6-1.4).

2. A cement mixture according to claim 1, characterized in that: the grain size of the steel slag raw material is 1-10mm, and the grain size of the steel slag powder obtained by grinding treatment is less than or equal to 0.8 mm.

3. A cement mixture according to claim 1, characterized in that: the coating also comprises the following raw material components in parts by weight: 2-7 parts of potassium hydroxide and 6-12 parts of modified hollow glass beads;

the preparation method of the modified hollow glass bead comprises the following steps: the hollow glass beads are modified by adopting a silane coupling agent.

4. The cement mixture as claimed in claim 4, wherein the concrete operation of modifying the hollow glass beads by using the silane coupling agent is as follows: soaking the hollow glass beads in 0.5-1% silane coupling agent aqueous solution for 1-2h, taking out and drying to obtain the modified hollow glass beads.

5. A cement mixture according to claim 4, characterized in that: the particle size of the modified hollow glass bead is 50-100 μm.

6. A method of preparing a cement mixture according to claim 1 or 2, comprising the steps of:

a. preparing steel slag powder;

b. the raw material components of the cement mixture are mixed and ground into the cement mixture.

7. A method of preparing a cement mixture according to any one of claims 3 to 5, comprising the steps of:

a. preparing steel slag powder;

b. preparing modified hollow glass beads;

c. the raw material components of the cement mixture are mixed and ground into the cement mixture.

Technical Field

The invention relates to the technical field of concrete building materials, in particular to a cement mixture and a preparation method thereof.

Background

The steel slag is a waste slag discharged in the steel-making process. At present, the annual discharge amount of steel slag in China can reach hundreds of millions of tons, but the utilization rate of the steel slag is less than 17 percent, so that a large amount of steel slag is accumulated. The steel slag piled up not only occupies a large amount of land resources, but also can cause serious environmental pollution.

The steel slag mainly comprises lining materials eroded in the steel-making process, oxides formed by molten iron and metal elements contained in scrap steel, silt, a slagging agent, a coolant, an oxidant, a deoxidation product, a desulfurization product and the like. The steel slag has the excellent performances of high compressive strength, high hardness, good wear resistance, corrosion resistance and the like. The steel slag is applied to the cement mixture and used for preparing the concrete mixture, so that the compressive strength of the concrete mixture is improved, and the waste utilization of the steel slag can be realized.

However, when the steel slag is added into the cement mixture, the bonding performance between the steel slag and the matrix of the concrete mixture is poor in the concrete mixture prepared by adopting the cement mixture, so that the steel slag is not beneficial to obtaining the concrete mixture with high compressive strength, and the application of the steel slag in the cement mixture is severely restricted.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide the following steps: provides a cement mixture to achieve the effects of improving the compressive strength of a concrete mixture prepared by adopting the cement and realizing the utilization of steel slag waste.

The first purpose of the invention is realized by the following technical scheme:

the cement mixture comprises the following raw material components in parts by weight: 60-75 parts of silicate cement clinker, 4-10 parts of gypsum, 5-10 parts of limestone, 8-15 parts of mineral powder, 10-15 parts of steel slag powder and 2-5 parts of redispersible latex powder;

the preparation of the steel slag powder comprises the following steps: grinding the steel slag raw material to obtain steel slag powder, and adding a grinding-aid combined additive accounting for 1.3-2.2% of the weight of the steel slag raw material during the grinding treatment, wherein the grinding-aid combined additive comprises borax and colloidal graphite powder, and the mass ratio of the borax to the colloidal graphite powder is 1 (0.6-1.4).

By adopting the scheme, the invention adopts a large amount of steel slag powder in the cement: firstly, the waste utilization of the steel slag is realized, and the phenomena of land resource occupation and environmental pollution caused by steel slag accumulation can be reduced; in addition, the steel slag powder prepared from the steel slag raw material has high compressive strength, so the concrete mixture prepared from the cement mixture has the characteristic of high compressive strength.

In the preparation step of the steel slag powder, a grinding-aid combined additive consisting of borax and colloidal graphite powder is added during grinding treatment. Along with the grinding treatment, the borax and the colloidal graphite powder are attached to the surfaces of the steel slag particles, so that the growth of cracks of the steel slag particles is facilitated, and the steel slag particles can be prevented from being combined again, thereby accelerating the grinding treatment process and improving the yield and the efficiency of the steel slag powder.

Borax is adhered to the particle surfaces of the steel slag powder obtained by grinding treatment, and the re-dispersible emulsion powder contains polyvinyl alcohol. When the cement mixture is adopted to prepare concrete mixture, borax on the surface of steel slag powder particles and polyvinyl alcohol can form a gel network structure, so that the connection performance between the steel slag powder and the concrete mixture matrix is greatly improved, and the compressive strength of the concrete mixture is greatly improved. Moreover, the colloidal graphite powder also adhered to the surface of the steel slag powder particles can improve the alkali resistance of the gel network structure, thereby further improving the interfacial strength of the steel slag powder particles and further improving the overall strength of the concrete mixture.

The invention is further configured to: the grain size of the steel slag raw material is 1-10mm, and the grain size of the steel slag powder obtained by grinding treatment is less than or equal to 0.8 mm.

The invention is further configured to: the coating also comprises the following raw material components in parts by weight: 2-7 parts of potassium hydroxide and 6-12 parts of modified hollow glass beads;

the preparation method of the modified hollow glass bead comprises the following steps: the hollow glass beads are modified by adopting a silane coupling agent.

By adopting the scheme, the hollow glass bead is a hollow glass sphere with tiny size, belongs to an inorganic non-metallic material, has the particle size range of 10-180 mu m, is light in weight and small in density, and has the bulk density of 0.1-0.25g/m³. The main chemical components of the hollow glass beads comprise silicon dioxide and aluminum oxide, in the modification treatment process, the silane coupling agent is used for modifying the surfaces of the hollow glass beads, and the silicon dioxide and aluminum oxide components on the surfaces of the hollow glass beads are activated by the silane coupling agent to form active silicon dioxide and active aluminum oxide. Adding the modified hollow glass micro-beads into the water of the inventionIn the case of concrete mixtures formulated with the cement of the invention:

on one hand, the modified hollow glass beads can improve the fluidity of the concrete mixture, improve the workability of the concrete mixture and reduce the water consumption, so that in the solidification process of the concrete mixture, because cavities left by water evaporation are reduced, the compactness of the concrete mixture is improved, the strength of the concrete mixture is improved, and the modified hollow glass beads with small particle sizes can fill the gaps among cement particles, so that the compactness of the concrete mixture is further improved, and the strength of the concrete mixture is further improved;

in another aspect, the cement mixture formulation of the present invention has gypsum as a retarder and the major chemical component is calcium sulfate hydrate. When the cement mixture is used for preparing concrete mixtures, potassium hydroxide and calcium sulfate in gypsum react to generate calcium hydroxide under the action of the added mixing water. The calcium hydroxide can react with the active silicon dioxide and the active aluminum oxide on the surfaces of the modified hollow glass beads to generate stable calcium silicate hydrate and calcium aluminate hydrate, so that the hardening of the concrete mixture is facilitated, the strength of the concrete mixture is increased, the coupling performance between the modified hollow glass beads and the matrix of the concrete mixture can be improved, the interface strength around the modified hollow glass beads is improved, and the compressive strength of the concrete mixture is facilitated to be improved;

moreover, concrete mixture is at the solidification in-process, because the cavity that the moisture evaporation left reduces for concrete mixture's compactness improves, nevertheless simultaneously, because modified hollow glass microballon has the characteristics that matter is light, density is little, so the density of concrete mixture has been reduced to a certain extent, promptly under the prerequisite that improves concrete mixture intensity, concrete mixture's density rising range is less, and this has important meaning and usage to the engineering that needs reduce concrete mixture dead weight.

The invention is further configured to: the concrete operation of modifying the hollow glass beads by adopting the silane coupling agent is as follows: soaking the hollow glass beads in 0.5-1% silane coupling agent aqueous solution for 1-2h, taking out and drying to obtain the modified hollow glass beads.

The invention is further configured to: the particle size of the modified hollow glass bead is 50-100 μm.

By adopting the scheme, under the cement formula components, the modified hollow glass microspheres with proper particle sizes can better utilize the advantage of the micro particle sizes per se to fill gaps among cement particles, so that the compactness of the concrete mixture is further improved, and the strength of the concrete mixture is further improved.

Object two of the present invention: the preparation method of the cement mixture comprises the following steps:

a. preparing steel slag powder;

b. the raw material components of the cement mixture are mixed and ground into the cement mixture.

The third purpose of the invention is that: the preparation method of the cement mixture comprises the following steps:

a. preparing steel slag powder;

b. preparing modified hollow glass beads;

c. the raw material components of the cement mixture are mixed and ground into the cement mixture.

In conclusion, the invention has the following beneficial effects:

1. according to the invention, a large amount of steel slag powder is adopted in the cement, so that the concrete mixture prepared from the cement mixture has the characteristic of high compressive strength, and the waste utilization of the steel slag is realized;

2. in the preparation step of the steel slag powder, a grinding-aid combined additive consisting of borax and colloidal graphite powder is added during grinding treatment, so that the grinding treatment process can be accelerated, and the yield and efficiency of the steel slag powder are improved;

3. when the cement mixture is adopted to prepare concrete mixture, borax on the surface of steel slag powder particles can form a gel network structure with polyvinyl alcohol in a matrix of the concrete mixture, so that the compressive strength of the concrete mixture is improved, and the colloidal graphite powder adhered to the surfaces of the steel slag powder particles can improve the alkali resistance of the gel network structure, so that the overall strength of the concrete mixture is further improved;

4. according to the invention, the modified hollow glass beads with tiny particle size are added into the component formula of the cement, so that the fluidity, the workability and the compressive strength of the concrete mixture can be improved;

5. the modified hollow glass beads with proper particle size can fill gaps among cement particles, so that the compactness and compressive strength of the concrete mixture are further improved;

6. when the cement formula comprises the potassium hydroxide and the modified hollow glass beads, in the process of preparing the concrete mixture, the potassium hydroxide reacts with calcium sulfate in gypsum to generate calcium hydroxide, and the calcium hydroxide reacts with active silicon dioxide and active aluminum oxide on the surfaces of the modified hollow glass beads to generate stable calcium silicate hydrate and calcium aluminate hydrate, so that the interface strength around the modified hollow glass beads can be improved, and the overall strength of the concrete mixture is improved;

7. when the cement formula comprises the potassium hydroxide and the modified hollow glass beads, although the concrete mixture prepared by the cement has higher compactness, the density of the concrete mixture is reduced to a certain extent because the modified hollow glass beads have the characteristics of light weight and small density, and the cement formula has important significance for projects which need high compressive strength and simultaneously need to reduce the self weight of the concrete mixture.

Detailed Description

The present invention will be described in further detail below.

In the following examples:

the fineness of the adopted portland cement clinker is less than or equal to 2.0;

the particle size of the modified hollow glass bead is 50-100 μm.

The adopted silane coupling agent is KH560 silane coupling agent;

the physicochemical parameters of the steel slag raw materials used are shown in table 1.

TABLE 1 physicochemical parameters of the steel slag raw materials