Modified slag powder and preparation method thereof

Abstract

The invention relates to a modified slag powder and a preparation method thereof. The preparation method comprises the following steps: performing heat treatment on the silico-calcium slag to obtain the heat-treated silico-calcium slag; mixing the heat-treated silico-calcium slag with coal ash, slag, gypsum, a cement grinding aid and an additive and grinding to obtain the modified slag powder. According to the preparation method, the silico-calcium slag powder is prepared by use of the silico-calcium slag by-product of producing alumina from the coal ash, and therefore, the application ways of the silico-calcium slag are expanded and the performance indices such as the strength of the concrete can be improved; on the other hand, the modified slag powder prepared by use of the method is superior to common blast furnace slag powder in both early strength and long-term strength, and the various indices at least conform to the standards of the national S95 grade slag powder, and therefore, the modified slag powder can be used as a cement or concrete admixture; the production operation process of the modified slag powder is simple and convenient and the problems of consumption and high value utilization of the silico-calcium slag can be effectively solved; in short, the modified slag powder has great popularization and application value.

Description

technical field

[0001] The invention relates to the field of building materials, in particular to a modified slag powder and a preparation method thereof. Background technique

[0002] It is reported that Inner Mongolia has accumulated more than 800 billion tons of coal reserves, ranking first in China; at the same time, with the implementation of the national "West-to-East Electricity Transmission" strategy, large-scale thermal power plants fueled by coal in the central and western parts of Inner Mongolia and its The surrounding area has been vigorously developed. With the transmission of electricity, about 12 million tons will be emitted every year, Al 2 o 3 High-alumina fly ash with a content of about 50%, and its stockpile over the years has exceeded 100 million tons.

[0003] In order to efficiently utilize these high-alumina fly ash, coupled with the gradual reduction of bauxite resources in my country, there are more and more cases of using high-alumina fly ash, po...

Examples

Embodiment 1

[0032] Carry out heat treatment on the silicon-calcium slag (the same below) obtained by the method described in CN103332710A: heat-air-dry the silicon-calcium slag at 105° C. to remove moisture, and then burn at 600° C. for 100 minutes to obtain heat-treated silicon-calcium slag;

[0033] In parts by mass, with 54 parts of heat-treated calcium silicate slag, 10 parts of fly ash, 30 parts of slag, 5 parts of desulfurized gypsum, 0.15 parts of CGA, AS cement grinding aid and 0.85 parts of potassium sulfate, carbonic acid The mixture of sodium was mixed and milled for 20 minutes by a tube mill to prepare modified slag powder with a specific surface area of ​​520m 2 / kg.

[0034] After testing, the final modified slag powder has a fluidity ratio of 103%, a 28-day activity index of 109%, a chloride ion content of 0.04%, and a sulfur trioxide content of 2.5%, which fully meet GB / T 18046- The requirements for S105 slag powder in 2008.

Embodiment 2

[0036] Burn silicon-calcium slag at 300°C for 120 minutes to obtain heat-treated silicon-calcium slag;

[0037] In parts by mass, 60 parts of heat-treated calcium silicate slag, 15 parts of fly ash, 20 parts of slag, 4 parts of desulfurized gypsum, 0.1 part of TM, CAS, ZM cement grinding aid and 0.9 part of sodium phosphate , was ground for 20 minutes by a tube mill to prepare modified slag powder with a specific surface area of ​​420m 2 / kg.

[0038] After testing, the final modified slag powder has a fluidity ratio of 102%, a 28-day activity index of 96%, a chloride ion content of 0.04%, and a sulfur trioxide content of 2.6%, fully meeting GB / T 18046- S95 slag powder requirements in 2008.

technical field

[0001] The invention relates to the field of building materials, in particular to a modified slag powder and a preparation method thereof. Background technique

[0002] It is reported that Inner Mongolia has accumulated more than 800 billion tons of coal reserves, ranking first in China; at the same time, with the implementation of the national "West-to-East Electricity Transmission" strategy, large-scale thermal power plants fueled by coal in the central and western parts of Inner Mongolia and its The surrounding area has been vigorously developed. With the transmission of electricity, about 12 million tons will be emitted every year, Al 2 o 3 High-alumina fly ash with a content of about 50%, and its stockpile over the years has exceeded 100 million tons.

[0003] In order to efficiently utilize these high-alumina fly ash, coupled with the gradual reduction of bauxite resources in my country, there are more and more cases of using high-alumina fly ash, po...

Examples

Embodiment 1

[0032] Carry out heat treatment on the silicon-calcium slag (the same below) obtained by the method described in CN103332710A: heat-air-dry the silicon-calcium slag at 105° C. to remove moisture, and then burn at 600° C. for 100 minutes to obtain heat-treated silicon-calcium slag;

[0033] In parts by mass, with 54 parts of heat-treated calcium silicate slag, 10 parts of fly ash, 30 parts of slag, 5 parts of desulfurized gypsum, 0.15 parts of CGA, AS cement grinding aid and 0.85 parts of potassium sulfate, carbonic acid The mixture of sodium was mixed and milled for 20 minutes by a tube mill to prepare modified slag powder with a specific surface area of ​​520m 2 / kg.

[0034] After testing, the final modified slag powder has a fluidity ratio of 103%, a 28-day activity index of 109%, a chloride ion content of 0.04%, and a sulfur trioxide content of 2.5%, which fully meet GB / T 18046- The requirements for S105 slag powder in 2008.

Embodiment 2

[0036] Burn silicon-calcium slag at 300°C for 120 minutes to obtain heat-treated silicon-calcium slag;

[0037] In parts by mass, 60 parts of heat-treated calcium silicate slag, 15 parts of fly ash, 20 parts of slag, 4 parts of desulfurized gypsum, 0.1 part of TM, CAS, ZM cement grinding aid and 0.9 part of sodium phosphate , was ground for 20 minutes by a tube mill to prepare modified slag powder with a specific surface area of ​​420m 2 / kg.

[0038] After testing, the final modified slag powder has a fluidity ratio of 102%, a 28-day activity index of 96%, a chloride ion content of 0.04%, and a sulfur trioxide content of 2.6%, fully meeting GB / T 18046- S95 slag powder requirements in 2008.