One of the main functions of converter steelmaking is to remove P, s and other harmful impurities in hot metal (scrap), so it is necessary to add lime and other slag agents in converter smelting. Lime forms calcium ferrite or dicalcium ferrite under the action of converter slag (FeO), and forms stable compound compound with P and s in hot metal to achieve the purpose of removing P and S. the reaction requires certain reaction conditions and time, and consumes FeO in slag. Therefore, the converter smelting time is prolonged and the consumption of oxygen and iron metal in converter is increased.

Calcium ferrite compound dephosphorization agent with calcium ferrite as the main component was prepared by using high quality Cao as base material and adding some reaction auxiliaries. It has the following functions and advantages when it is used in converter smelting

1. It can form slag quickly after adding it before converter smelting, fill up the reflection space before slagging, and play dephosphorization function in low temperature period of converter.

2. When the converter end temperature is high and the converter slag is not good, it can effectively improve the oxidizability of converter slag, reduce the slag temperature, help converter slag melting, and play an important role in restraining the return of P in the later stage of converter smelting.

3. The dephosphorization function of lime can be improved when it is used together with lime added in converter, and the effect is better than that of lime alone.

4. The iron oxide (FeO) in the dephosphorization agent can reach about 50%, which can reduce the oxygen consumption for converter blowing. If the addition amount reaches 10-15kg-s steel, the oxygen consumption of converter can be reduced by 20%, and the iron element in calcium ferrite can improve the metal yield of converter.

5. Calcium ferrite compound dephosphorization agent has the characteristics of low melting point and helps converter slag melting. It can replace the converter when it is used. It is very beneficial to improve the service life of the furnace and reduce environmental pollution. It can realize fluorine-free steelmaking.

6. It can shorten the blowing cycle by 1-2 minutes, improve the converter operation rate and achieve remarkable economic benefits.