Artificial steel slag aggregate and preparation method and application thereof

Abstract

The invention discloses an artificial steel slag aggregate and a preparation method and application thereof. The preparation method comprises the following steps: step 1, grinding steelmaking tailingsby using a ball mill to obtain uniform steel slag powder; 2, weighing Portland cement, an admixture fine powder and steel slag powder, and conducting uniform mixing to obtain an aggregate raw material; 3, preparing an additive aqueous solution; 4, putting the aggregate raw material into a ball forming mill, and uniformly spraying the additive aqueous solution prepared in the step 3 to form balls,so as to obtain spherical artificial steel slag aggregate; step 5, putting the pelletized aggregate into a closed environment or a natural environment for pre-curing; and step 6, putting the pre-cured aggregate into a carbonization device for carbonization treatment to finally prepare the artificial steel slag aggregate. The artificial steel slag aggregate prepared by the method can achieve the goals of safety and high strength, the crushing index of the aggregate can reach 9.26% and reach the I-grade aggregate use standard, the production process is simple, the solid waste is recycled, the carbon dioxide is absorbed and cured, and the artificial steel slag aggregate is free of burning, low-carbon and environment-friendly.

Description

technical field [0001] The invention belongs to the technical field of building materials, and in particular relates to an artificial steel slag aggregate and a preparation method and application thereof. Background technique [0002] In the iron and steel smelting process, for every ton of steel produced, 800-1500kg of by-product steel slag will be produced. The main mineral components of steel slag are dicalcium silicate, calcium silicon oxide, calcium aluminum oxide, and iron. Due to the complex mineral phase composition and low chemical activity, steel slag is difficult to use directly as building materials. In addition, steel slag contains a large amount of free calcium oxide and magnesium oxide. These components will cause volume deformation and cracking in the late stage of hydration and reaction expansion. Due to the limitations of the above two main problems, the steel slag produced by steelmaking is difficult to be industrially utilized. According to reports, the a...

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Problems solved by technology

Due to the complex composition of mineral phases and low chemical activity, it is difficult to use steel slag directly as a building material. In addition, steel slag contains a large amount of free calcium oxide and magnesium oxide. These components will cause volume deformation and cracking in the late stage of hydration and reaction expansion.

Due to the limitations of the above two main problems, the steel slag produced by steelmaking is difficult to be utilized industrially. According to reports, the accumulation of steel slag in my country has reached 1.2 billion tons in 2016, but the actual utilization rate of steel slag is less than 20%.

The method for preparing modified steel slag in this patent is complicated, and the modification requires sulfuric acid reaction; high and low temperature treatment; and the addition of modified bagasse, which is not conducive to environmental protection and resource conservation

The patent application with the publication number CN201910250979 discloses a steel slag modification method, including firstly adding a modifier to the high-temperature converter steel slag, then cooling it to 600-800°C, and then placing it in a sealed environment for water spray heat treatment , steel slag after powdering is obtained; then steel slag after powdering is mixed with clay and quicklime according to the mass ratio of 45:(12-18):(37-43) and stirred evenly to obtain a mixture; finally the mixture is Calcined at 1300-1450°C for 20-30min, cooled to room temperature, to obtain steel slag with active cement clinker, using this steel slag to replace 30-35% cement molding mortar, the compressive strength can reach 60.5-61.3MPa in 28 days, this method needs to be Steel slag is processed during the steelmaking process, and the mixture is then calcined at a high temperature of 1300-1450°C. Many procedures are difficult to apply in practice, and high-temperature calcination is not conducive to energy saving.

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