The invention belongs to an induction melting furnace smelting production process. The bulk requirements of various specifications of ferromanganese alloys used in steelmaking are generally in the range of 5-60mm. When ferromanganese manufacturers use the manufacturer or distribution department to crush large ferromanganese into standard pieces, the under-sieve ferromanganese powder less than 5mm accounts for more than 5%. The current method of using these wastes is mainly to return to the blast furnace or electric solitary furnace for re-smelting. The disadvantage of this method is its large scale; changing the operating process of normal ferromanganese production has poor economy and manufacturability.
Remelting ferromanganese powder with an intermediate frequency induction electric furnace to produce recycled ferromanganese. This method can flexibly organize the production of tens of kilograms to hundreds of tons, avoiding the shortcomings of the return method, and has great economic and social benefits.
The principle of induction melting furnace smelting is that the charge generates electromagnetic induction current to heat itself to melt. Ferromanganese powder has poor magnetic conductivity, electrical conductivity, and thermal conductivity. It does not have the characteristics of self-heating. The present invention uses the "self-heating" characteristic of ferromanganese solution to indirectly heat the ferromanganese powder to the melting process. The operation method is as follows:
There are two methods for smelting ferromanganese in the first furnace with the new knotted lining of the induction melting furnace. The first is to add steel rods or iron nuggets into the furnace at the same time as the ferromanganese powder. When a little liquid is generated, the steel rods or iron nuggets are taken out and then the ferromanganese powder is added, and the ferromanganese powder is melted by the "self-heating" characteristic of the existing liquid. The other method is to smelt a furnace of iron and steel and pour it out, and then add a very small amount of liquid, then add ferromanganese powder successively, and use the furnace wall heat storage and the melt to "self-heat" to melt the ferromanganese powder until the furnace is full. The next smelting process is to add the ferromanganese powder to the full furnace by adding 1/5 to 1/3 of the molten iron left over from the previous ferromanganese furnace. The ferromanganese powder is added in more than five batches per furnace.
Each batch does not exceed 1/5 of the capacity. After each two batches of melting, remove the liquid surface and the slag sticking to the furnace wall. After the molten ferromanganese is cast into a square billet with a cross-section of 60mm-120mm, it is crushed into a block of ferromanganese with a particle size of less than 60mm to be the finished product.
The process of smelting ferromanganese has no special requirements for the various equipment and lining materials of the induction melting furnace.
The chemical composition of ferromanganese powder is slightly changed after smelting into ferromanganese, and the recovery rate is greater than 75~0u
The power consumption and productivity of smelting ferromanganese are equivalent to those of smelting iron and steel products.
The invention has been smelted to produce more than 500 tons of ferromanganese, and it has been used for steelmaking to achieve the expected purpose.
