Method for eliminating f-CaO in steel slag through water soaking hot closing

Abstract

The invention discloses a method for eliminating f-CaO in steel slag through water soaking hot closing. The method is characterized in that water is sprayed from the top of a hot closing container; the lower part is gradually soaked in water to generate saturated steam; saturated steam is simultaneously generated at the upper and lower parts in the container to realize the sufficient contact withf-CaO; along with the water filling, the water level in the container gradually rises; the contact with high-temperature water bath with the f-CaO in the refined steel slag is utilized, so that the elimination reaction of the f-CaO is sufficiently performed; after the steel slag is treated by the method, the f-CaO content in the steel tailing is stably lowered to a value below 3.0 percent; the inherent process defects of the conventional steel slag pressure-free hot closing treatment process are overcome; the instability of the steel slag is eliminated; the performance index meets the standardrequirements of industries of cement, building materials and the like; the method can be used for the fields of steel slag powder production, building material product production, road engineering and the like. The beneficial conditions are created for the resource utilization of the steel slag.

Description

technical field [0001] The invention belongs to the technical field of steel slag thermal braising, and in particular relates to a method for dissolving f-CaO in steel slag by soaking in water and thermal braising. Background technique [0002] When steel slag is used as a building material, there are strict requirements on f-CaO, water swellability, and metal content in steel slag. The lower the f-CaO content in steel tailings is, the lower the water swellability of steel slag is, and the better the stability is. In buildings, its stability can ensure the safety of buildings. Therefore, solving the problem of stability is the key and difficult point for steel slag to be used as building materials. Most of the converter slag f-CaO exceeds 5%, and conventional thermal braising technology exists Insufficient steam generation, insufficient saturation, etc. In addition, the final slag of the converter will inevitably contain molten steel, dead burnt burnt lime, and contains a la...

AI Technical Summary

Problems solved by technology

[0002] When steel slag is used as a building material, there are strict requirements on f-CaO, water swellability, and metal content in steel slag. The lower the f-CaO content in steel tailings is, the lower the water swellability of steel slag is, and the better the stability is. In buildings, its stability can ensure the safety of buildings. Therefore, solving the problem of stability is the key and difficult point for steel slag to be used as building materials. Most of the converter slag f-CaO exceeds 5%, and conventional thermal braising technology exists Insufficient steam generation, insufficient saturation, etc. In addition, the final slag of the converter will inevitably contain molten steel, dead burnt burnt lime, and contains a large amount of C with a dense structure and a high melting point. 2 S, C 3 Complex compounds such as S, etc., the average content of free calcium oxide (f-CaO) in steel slag is difficult to digest to less than 3%, and the f-CaO index of steel tailing slag cannot meet the national standard GB / T20491-2006, GBT258242010, metallurgical standard YBT41872009 and other standards Requirements, it is difficult to be used in road engineering, concrete, cement and other building materials

[0003] In the conventional steel slag heat treatment process, the high-temperature saturated steam generated by pumping water is quickly drained from the upper part, and the steel slag in the middle and lower parts of the tank cannot be effectively contacted in the early and middle stages of hot stewing water pumping. Block the gap between the steel slag, hinder the normal and uniform penetration of the follow-up water to the middle and lower parts, and the water vapor generated cannot normally go up and interact with the steel slag, resulting in the phenomenon of high-temperature red slag still existing in the pool during the slag discharge process after heating, and the f-CaO digestion reaction unable to perform adequately

In addition, there are some steel slag heat treatment methods that require a certain steam pressure in the heat vessel, but this treatment method may form high temperature and high pressure in the airtight heat vessel, and there is a risk of explosion

When an explosion occurs, the slag cover is lifted, and the steel slag splashes everywhere, which is prone to steel slag injury accidents