Method for synthesizing silicate building material from magnesium oxide and blast furnace slag

A technology for synthesizing silicate and blast furnace slag, used in cement production and other directions, can solve the problems of limited activation of slag activity, low practical value, limited recycling rate, etc., to achieve high mechanical strength and durability, high mechanical strength, technically sound effect

Inactive Publication Date: 2016-10-26
SHENYANG JIANZHU UNIVERSITY
View PDF5 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Magnesium oxide (MgO) is also a common alkaline oxide. Under normal temperature and pressure, the pH value of a saturated aqueous solution of MgO is only about 10.5, which has a limited stimulating effect on the activity of slag and has low practical value.
On the other hand, a large amount of tailings produced by industrial mining such as magnesite, dolomite, and brucite, as well as industrial waste residues such as boron mud, are rich in magnesium oxide, but the recycling rate is limited

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for synthesizing silicate building material from magnesium oxide and blast furnace slag
  • Method for synthesizing silicate building material from magnesium oxide and blast furnace slag
  • Method for synthesizing silicate building material from magnesium oxide and blast furnace slag

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0055] Magnesite tailings MgCO 3 The content is 95.0wt%. The ore is crushed and ground to a particle size of 150 μm or less. After roasting at 900°C for 0.5 hours, magnesium oxide is obtained. Mix magnesium oxide and slag evenly at a mass ratio of 1:9, and add an appropriate amount of mixing water (tap water) Mix well. Water consumption for mixing=(slag mass+magnesia mass)×10%+magnesia mass×50%. The mixture is sealed and stored away from light for 24 hours, then placed in a molding mold, and molded by 20MPa pressure. After molding, the sample was placed in a hydrothermal reaction kettle, heated to 200°C, kept at a constant temperature for 6 hours, and then cooled naturally. In the obtained silicate building material products, calcium silicate hydrate accounted for 69.2 wt%, and magnesium silicate hydrate accounted for 18.5% by weight. wt%. The average compressive strength of hydrothermally cured samples is 16.47MPa, such as Figure 1a ), the corresponding MgO dosage is 10w...

Embodiment 2

[0057] The difference from Example 1 is that the mass ratio of MgO and slag is adjusted to 1:3, the amount of mixing water = (slag mass + magnesium oxide mass) × 20% + magnesium oxide mass × 50%, and the hydrothermal reaction temperature, time Invariably, in the obtained silicate building material products, calcium silicate hydrate accounts for 52.4wt%, and magnesium silicate hydrate accounts for 40.0wt%, then the compressive strength of the cured body is reduced to 12.53MPa, such as Figure 1a ) shown.

Embodiment 3

[0059] The difference from Example 1 is that the mass ratio of MgO and slag is adjusted to 1:19, the amount of mixing water = (slag mass + magnesium oxide mass) × 5% + magnesium oxide mass × 50%, the molding pressure is 10MPa, and the hydrothermal Reaction temperature, time are constant, in the obtained silicate building material product, calcium silicate hydrate accounts for 74.3wt%, magnesium silicate hydrate 10.1wt%, then the compressive strength of cured body reduces to 9.81MPa, as Figure 1a ) shown.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
compressive strengthaaaaaaaaaa
compressive strengthaaaaaaaaaa
compressive strengthaaaaaaaaaa
Login to view more

Abstract

The invention specifically relates to a method for synthesizing a silicate building material from magnesium oxide and blast furnace slag, belonging to the field of recycling of industrial waste residues. The method adopts a hydrothermal curing process, and a cured product has high mechanical strength and can be used as a wall material of a building, a brick for a pedestrian trail, etc. The method comprises the following steps: subjecting magnesium slag tailings to crushing, screening and roasting; then uniformly mixing the roasted tailings with a proper amount of blast furnace slag powder and water and carrying out compression molding; and allowing calcium silicate hydrate and chrysotile calcium silicate hydrate to be formed and aggregated in virtue of the slag activation effect of MgO in a high-temperature saturated water vapor environment so as to obtain the building material with usage performance like high mechanical strength. The prepared building material is applicable as a wall material of a building, a brick for a pedestrian trail, etc.; and the method is applicable to recycling of magnesium-containing mine tailings like low-grade magnesite, dolomite and brucite and residues of boric sludge and the like.

Description

technical field [0001] The invention relates to the field of resource utilization of industrial waste slag, specifically a method for synthesizing silicate building material products using magnesium oxide and blast furnace slag. The hydrothermal curing process is adopted, and the cured product has relatively high mechanical strength and can be used as a building material. Wall materials, sidewalk bricks, etc. Background technique [0002] Blast furnace slag is the industrial waste slag formed by high-temperature melting and cooling of non-volatile impurities in furnace materials such as iron ore gangue, flux (limestone) and ash in fuel during the blast furnace ironmaking process. The main chemical composition is CaO , SiO 2 、Al 2 o 3 , MgO, of which CaO accounts for 30-50wt%, SiO 2 Accounting for 25-45wt%, Al 2 o 3 Accounting for 5-20 wt%, MgO accounting for 3-15 wt%. The discharge of blast furnace slag varies with ore grades and smelting methods. For example, when le...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C04B7/153
CPCC04B7/153C04B12/005Y02P40/10
Inventor 佟钰赵竹玉陶冶
Owner SHENYANG JIANZHU UNIVERSITY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap