Blast furnace blowing semi-coke additive and preparation and use method thereof

Abstract

The invention discloses a blast furnace injection semi-coke additive as well as a preparation method and a use method thereof, and belongs to the technical field of blast furnace coal injection. The additive comprises the following components in percentage by mass: 0.1-0.25% of a grinding aid, 58-80% of a composite waste residue type catalyst, 18-40% of a composite compound type catalyst and 1-4%of a dispersing agent. By adding the additive, the grindability and the ash melting point of semi-coke can be improved, the combustion effect is good, the injection amount of the semi-coke in a blastfurnace is greatly increased, the additive is suitable for large-scale popularization and application of blast furnace injection semi-coke, and a good foundation is laid for finally achieving completereplacement of coal with the semi-coke and achieving coal removal in a blast furnace injection system.

Description

technical field [0001] The invention relates to the technical field of blast furnace coal injection, in particular to a blast furnace injection semi-coke additive and a preparation and use method thereof. Background technique [0002] With the continuous increase of blast furnace injection volume, the demand for anthracite by iron and steel enterprises is increasing day by day. However, anthracite reserves only account for 10.9% of my country's coal reserves, and the scarcity is constantly highlighted, and the price is gradually rising. Substituting part of the expensive anthracite with low-priced fuel is one of the effective measures to reduce the cost of ironmaking. Therefore, various iron and steel plants are urgently seeking low-priced fuels that can not only reduce the coke ratio, but also reduce production costs as fuels in the ironmaking system. [0003] Semi-coke is a solid product of low-temperature dry distillation cascade transformation in low-metamorphism coal....

AI Technical Summary

Problems solved by technology

[0004] (1) The current general blast furnace pulverized coal injection process has a good effect on the mixed coal pulverization process of bituminous coal and anthracite, but when semi-coke is used instead of anthracite, due to the poor grindability of semi-coke, bituminous coal has reached The particle size requirements and semi-coke particles are still large, resulting in low pulverization efficiency and affecting the output of blast furnace pulverization. As a result, semi-coke can only replace part of anthracite for blast furnace injection, and most control semi-coke ratios are only 20-40. %

[0005] (2) The semi-coke powder produced by the current system has large particles and obvious sharp edges and corners, which makes the semi-coke powder have a far greater wear effect on the bag powder collector, conveying pipeline and spray gun than the bituminous anthracite powder , leading to a significant reduction in the service cycle of related equipment, which affects production efficiency and increases the risk of hidden dangers in production safety

However, the volatile content of semi-coke is generally about 10%. If the amount of semi-coke is further increased or completely replaced by bituminous coal, it will inevitably affect the combustion performance of the fuel.