阅读说明：本技术 一种硫铝酸盐水泥基混凝土及其制备工艺 (Sulphoaluminate cement-based concrete and preparation process thereof ) 是由 何士成 陈佩圆 李进 曹可 王浩 沈文峰 于 2019-10-28 设计创作，主要内容包括：本发明公开一种硫铝酸盐水泥基混凝土及其制备工艺,包括以下原料的重量份组成：硫铝酸盐水泥14.076-16.565％、工业副产石膏0.828-2.484％、细沙24％、石子52％、水7.44％、缓凝剂0.014-0.017％。包括以下步骤：S1、原料按照重量份称取,先将原料中的水泥、副产石膏放入搅拌机中干搅拌,再放入细沙和石子搅拌3min至均匀；S2、将所称的抗坏血酸加入称量好的水中,搅拌使其溶解；S3、将S2所制溶液加入搅拌机中,搅拌3min至均匀；S4、搅拌结束后,装模并振捣成型,移放至养护箱养护后进行脱模,得到成品。通过使用工业副产石膏替代部分硫铝酸盐水泥,控制其使用量占混凝土总质量的0.828-2.484％,外掺微量的Vc,既可以弥补硫铝酸盐水泥基混凝土凝结时间短的问题,也可以提高混凝土的强度性能和可塑性能。(The invention discloses sulphoaluminate cement-based concrete and a preparation process thereof, wherein the sulphoaluminate cement-based concrete comprises the following raw materials in parts by weight: 14.076-16.565% of sulphoaluminate cement, 0.828-2.484% of industrial by-product gypsum, 24% of fine sand, 52% of stones, 7.44% of water and 0.014-0.017% of retarder. The method comprises the following steps: s1, weighing the raw materials in parts by weight, putting the cement and the byproduct gypsum in the raw materials into a stirrer for dry stirring, and then putting the fine sand and the stones into the stirrer for stirring for 3min to be uniform; s2, adding the weighed ascorbic acid into weighed water, and stirring to dissolve the ascorbic acid; s3, adding the solution prepared in the S2 into a stirrer, and stirring for 3min until the solution is uniform; and S4, after stirring, filling the mixture into a mold, vibrating the mixture for molding, moving the mixture into a curing box for curing, and then demolding to obtain a finished product. By using the industrial by-product gypsum to replace part of sulphoaluminate cement, controlling the use amount of the gypsum to be 0.828-2.484 percent of the total mass of the concrete, and doping a trace amount of Vc, the problem of short setting time of sulphoaluminate cement-based concrete can be solved, and the strength performance and the plasticity of the concrete can be improved.)

1. The sulphoaluminate cement-based concrete is characterized by comprising the following raw materials in parts by weight: 14.076-16.565% of sulphoaluminate cement, 0.828-2.484% of industrial by-product gypsum, 24% of fine sand, 52% of stones, 7.44% of water and 0.014-0.017% of externally-doped retarder.

2. The sulfoaluminate cement-based concrete of claim 1, wherein the cement to water cement ratio is 0.45.

3. The sulphoaluminate cement-based concrete according to claim 1, wherein the sulphoaluminate cement is a quick setting fast setting cement clinker having a cement index designation of 42.5R.

4. The sulfoaluminate cement-based concrete of claim 1, wherein the industrial by-product gypsum is desulfurized gypsum (CaSO) as a major component ₄·2H ₂O), the character appeared as a pale yellow powder.

5. The sulphoaluminate cement-based concrete according to claim 1, wherein the retarder is ascorbic acid (C) ₆H ₈O ₆) And the amount of the retarder is 1/1000 of the amount of the cement.

6. Process for the preparation of sulphoaluminate cement-based concrete according to any one of claims 1 to 5, comprising the following steps:

s1, weighing the raw materials according to the weight parts, putting the cement and the byproduct gypsum in the raw materials into a stirrer for dry stirring until the cement and the byproduct gypsum are uniform, and then putting the fine sand and the stones into the stirrer for stirring for 3min to be uniform;

s2, adding the weighed ascorbic acid into weighed water, and stirring until the ascorbic acid is completely dissolved;

s3, adding the solution prepared in the S2 into a stirrer, and stirring the slurry for 3min to be fully and uniformly;

and S4, after the materials are stirred, transferring the materials into a mold for vibration molding, and then, transferring the mold to a curing box for curing and demolding to obtain a finished product.

7. The process for producing a sulphoaluminate cement-based concrete according to claim 6, wherein the curing temperature of the curing box in the step S3 is controlled to be 22-24 ℃.

8. The process for producing a sulphoaluminate cement-based concrete according to claim 6, wherein the humidity of curing the curing box in the step S3 is controlled to be 90-92%.

Technical Field

The invention belongs to the field of high added value treatment and utilization of industrial byproduct gypsum, and particularly relates to sulphoaluminate cement-based concrete and a preparation method thereof.

Background

The industrial by-product gypsum mainly comprises desulfurized gypsum, phosphogypsum, titanium gypsum, fluorgypsum, citric acid gypsum, boron gypsum and the like. With the yield of phosphate fertilizer, citric acid, titanium dioxide, coal and the like in China reaching the world first, the emission of industrial byproduct gypsum produced therewith also reaches the world first. The gypsum has complex components, more impurities, high treatment difficulty, land occupation by accumulation and environmental pollution. With the increase of environmental protection in China, the industrial by-product gypsum becomes an important obstacle for restricting the development of related production enterprises, and even the enterprises are in a semi-stop state because the industrial by-product gypsum cannot be treated. Therefore, the problem of reasonably and efficiently utilizing the industrial byproduct gypsum is to be solved. The application of the industrial by-product gypsum in building materials is the most potential application direction, and the industrial by-product gypsum can be consumed more rapidly, and the construction materials can be prepared, so that the cost of the building materials can be reduced, and the industrial by-product gypsum is highly concerned and expected in academia and industry. The industrial by-product gypsum is an industrial by-product with calcium sulfate as a main component, and mainly exists in the form of dihydrate gypsum, and a large number of researches show that if the industrial by-product gypsum is directly doped into common silicate-based concrete, the setting time of the concrete is seriously prolonged, and the mechanical strength is reduced. So far, the application of the industrial by-product gypsum in the ordinary portland cement-based material has not been broken through.

In order to efficiently utilize the industrial byproduct gypsum, the invention provides the application of the industrial byproduct gypsum in sulphoaluminate cement-based concrete on a large number of tests. The test result shows that the industrial by-product gypsum can be simultaneously doped into the sulphoaluminate cement-based concrete in the form of sulphoaluminate cement or fine aggregate substitute, and under the condition of a certain doping amount, the mechanical strength of the sulphoaluminate cement-based concrete can not be reduced, and the mechanical strength can be improved by about 14 percent. The invention not only can efficiently treat and highly utilize the industrial byproduct gypsum, reduce the environmental pollution caused by the industrial byproduct gypsum and the difficult problems of treatment and utilization, but also can reduce the cost of the sulphate aluminum cement-based concrete, improve the mechanical strength of the sulphate aluminum cement-based concrete under the condition of a certain mixing amount, and prepare a more efficient composite gelling system. Therefore, the method solves the problem of utilization of industrial byproduct gypsum, reduces the cost of the sulphoaluminate cement-based concrete, and has important economic, environmental, social and application values.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide sulphoaluminate cement-based concrete and a preparation method thereof, which solve the problem that the industrial byproduct gypsum is difficult to utilize and treat, further realize the purpose of efficiently and largely utilizing the industrial byproduct gypsum on the basis, and have very wide application prospects.

The purpose of the invention can be realized by the following technical scheme:

the sulphoaluminate cement-based concrete comprises the following raw materials in parts by weight: 14.076-16.565% of sulphoaluminate cement, 0.828-2.484% of industrial by-product gypsum, 24% of fine sand, 52% of stones, 7.44% of water and 0.014-0.017% of externally-doped retarder.

Further, the water cement ratio of the cement to the water is 0.45.

Furthermore, the sulphoaluminate cement is quick-hardening and quick-drying cement clinker, and the cement index is 42.5R.

Further, the main component of the industrial by-product gypsum is desulfurized gypsum (CaSO) ₄·2H ₂O), the character appeared as a pale yellow powder.

Further, the retarder is ascorbic acid (C) ₆H ₈O ₆) And the amount of the retarder is 1/1000 of the amount of the cement.

The preparation process of the sulphoaluminate cement-based concrete comprises the following steps:

s1, weighing the raw materials according to the weight parts, putting the cement and the byproduct gypsum in the raw materials into a stirrer for dry stirring until the cement and the byproduct gypsum are uniform, and then putting the fine sand and the stones into the stirrer for stirring for 3min to be uniform;

s2, adding the weighed ascorbic acid into weighed water, and stirring until the ascorbic acid is completely dissolved;

s3, adding the solution prepared in the S2 into a stirrer, and stirring the slurry for 3min to be fully and uniformly;

and S4, after the materials are stirred, transferring the materials into a mold for vibration molding, and then, transferring the mold to a curing box for curing and demolding to obtain a finished product.

Further, the curing temperature of the curing box in the step S4 is controlled to be 22-24 ℃.

Further, the humidity of the curing box curing in the step S4 is controlled to be 90-92%.

The invention has the beneficial effects that:

1. compared with the prior art, the invention has the beneficial effects that: not only can consume the industrial by-product gypsum, solve the problem of difficult treatment, but also recover and promote the normal operation of the factory; but also can reduce the cost of building materials, realize the industrial waste utilization, and reduce the pollution of industrial byproduct gypsum to air, water and soil, thereby achieving multiple purposes.

2. The preparation method is simple, low in economic cost, high in yield and wide in industrial production prospect, is an important way for realizing effective utilization of industrial byproduct gypsum, and meets the requirement of environmental protection and green concept.

Drawings

FIG. 1 is a graph showing the data on the compressive strength of a sulphoaluminate cement-based concrete in the case where the industrial by-product gypsum of example 1 of the present invention is substituted for 5% cement.

FIG. 2 is a graph showing the data on the compressive strength of a sulphoaluminate cement-based concrete in the case where 10% of cement is replaced by industrial by-product gypsum in example 2 of the present invention.

FIG. 3 is a graph showing the data on the compressive strength of a sulphoaluminate cement-based concrete in the case where 15% of cement is replaced by industrial by-product gypsum in example 3 of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.