A kind of semi-coke additive for blast furnace injection and its preparation and use method

Abstract

The invention discloses a semi-coke additive for blast furnace injection and methods for preparing and using the same, and belongs to the technical field of blast furnace coal injection. The composition of the additive contains 0.1-0.25% of grinding aid, 58-80% of composite waste residue type catalyst, 18-40% of composite compound type catalyst and 1-4% of dispersant in terms of mass percentage. By adding this additive, the grindability and ash melting point of semi-coke can be improved, and the combustion effect can be improved, which greatly increases the amount of semi-coke injected in the blast furnace, and is suitable for large-scale popularization and application of semi-coke injected into blast furnaces. In the blast furnace injection system, semi-coke can be completely replaced by coal, which lays a good foundation for de-coalization.

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.