Functional steel slag powder

Abstract

The invention relates to functional steel slag powder. The raw materials comprise less than 2% by weight of metallic iron, less than 1.5% by weight of water and steel slags with the particle size less than 8 mm, a closed-circuit grinding technology through a tube mill is adopted, and after the steel slags are measured, the steel slags are fed into the tube mill to conduct powder grinding; the ground materials are fed into a powder selecting machine to conduct particle size classification, the specific surface area is 420 m<2>/kg, a 45-micron square hole screen screens out less than 5% of fine powder which is the functional steel slag powder, the 45-micron square hole screen screens out more than 5% of coarse powder, fine iron separation is conducted on the coarse powder through a dry-type magnetic separator, it is guaranteed that the functional steel slag powder metallic iron is less than 0.1%, and the coarse powder which is subjected to the fine iron separation is added to an additive which accounts for 0.5%-5% of unit-hour output of the tube mill before returning to the tube mill and sent to the tube mill to conduct closed-circuit grinding. The performance of concrete can be improved, the production cost is reduced, the damage of a mountainous pile of the steel slags on the ecological environment is reduced, the waste is turned into wealth, and the valuable land sources are saved.

Description

technical field [0001] The invention belongs to the technical field of comprehensive utilization of solid waste, and relates to functional steel slag powder. Background technique [0002] Steel slag is a by-product of the steelmaking process in steel plants, accounting for 10% to 13% of crude steel output. my country's crude steel output has exceeded 800 million tons per year, and the by-product steel slag has exceeded 100 million. The efficient utilization of steel slag is one of the important symbols of the technological progress of the modern iron and steel industry. In the United States, Germany, Japan and other countries with advanced industrial technology, the comprehensive utilization rate of steel slag is above 95%. However, the comprehensive utilization rate of steel slag in my country is less than 30%. Part of the discharge occupies land, causing waste of resources and deterioration of the ecological environment. It is one of the bulk industrial solid wastes that u...

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Problems solved by technology

[0007] However, due to the low early activity of steel slag powder and granulated blast furnace slag powder or fly ash, the early activity is low, and steel slag powder accounts for about 15% in the composite system composed of granulated blast furnace slag powder or fly ash. weight ratio, thus restricting the popularization and application of steel slag powder

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