Hot braising method for phosphorus removed slag and carbon removed slag

Abstract

The invention provides a hot braising method for phosphorus removed slag and carbon removed slag. The method comprises the following steps of: pouring hot phosphorus removed slag into a slag braising pit to parch the slag braising pit; pouring the phosphorus removed slag or the carbon removed slag into multiple parched slag braising pits respectively, turning over, dewatering and breaking the slag in each slag braising pit, then pouring another slag respectively, and repeating the operations of turning over, dewatering and breaking the slag till each slag braising pit is full of the slag; and covering the slag braising pits full of the slag with slag braising covers, and braising the slag in a three-section dewatering and braising mode. The hot braising method for the phosphorus removed slag and the carbon removed slag is simple and feasible, can reduce the potential safety hazard of blasting of the slag braising pits and effectively improve the slag braising efficiency and slag braising quality, and has remarkable economic benefits.

Description

technical field [0001] The invention relates to the technical field of processing hot steel slag in a steelmaking system, in particular to a thermal braising method for dephosphorization slag and decarburization slag. Background technique [0002] Clean steel production has always been one of the goals pursued by the steelmaking field. Due to the long process flow and large fluctuations in production operation of conventional converter smelting clean steel, it is easy to cause unstable quality of molten steel. In the 1990s, a new converter smelting process represented by "full three removals" appeared in Japan, and became one of the advanced processes for producing high-clean steel. At present, Japan's Sumitomo Metal Wakayama Plant, NKK Fukuyama Plant, Nippon Steel Muroran Plant, South Korea's Pohang Gwangyang Plant, and Hyundai Steel Tangjin Plant all use the "all three removal" process for large-scale production. Domestic Baosteel began to conduct research on BRP (Baoste...

AI Technical Summary

Problems solved by technology

First, blasting is easy to occur during the process of dumping slag in the slag pit, which poses certain hidden dangers to safe production

This is because the converter slag is a high-temperature liquid slag, which can reach above 1600°C at the highest temperature. The steel slag cannot be completely removed when it comes out of the pit. The remaining steel slag contains a certain amount of water, and the slag pit is humid. It is required that the steel slag in the roasting pit must be low temperature and dry. , but in the actual operation process, the roasted pit slag sometimes brings viscous steel slag, and it is easy to fire at this time

Second, due to irregular operations during slag dumping, slag turning, and water extraction, steel slag hardening or large pieces of red slag are prone to occur, which has always plagued steelmaking production

After the slag pit is completed, it enters the slag dumping stage. The general operation is to pour one furnace of high-temperature converter slag directly into a slag pit, and then use a hydraulic rake to turn the slag and pump water. If the converter slag is liquid slag or Viscous slag, the liquid slag will penetrate into the lower part of the steel slag, because the steel slag is too thick, the hydraulic rake cannot turn the steel slag through, and the steel slag will be hardened or large red slag will appear when the slag is stewed

Therefore, some steel mills require that liquid steel slag is not allowed to be poured into the slag pit, which puts forward higher requirements for steelmaking slag splash protection furnace, such as increasing the amount of slag splash protection furnace modifier, or prolonging the slag splash protection furnace time , to reduce the temperature of steel slag, so that liquid steel slag becomes low-temperature solid steel slag, but, due to the increase of raw material consumption and prolongation of smelting time, the cost of steelmaking has been increased, so this problem has not been completely solved