1990 Volume 76 Issue 11 Pages 1855-1862
As a process for the production of ferrochrome without electric energy as heat source, a new smelting reduction process with the top-and-bottom blowing converter was developed.
The special feature of this process is to separate the metal bath from top-blown oxygen jet by the thick molten slag layer.
The pilot plant test of 2 t/h production scale was conducted by the Research Association for New Smelting Technologies.
The results are summarized as follows ;
( 1 ) The operation of this process was stable. Scaling up of about 30 times in oxygen blowing rate was done without any problem.
( 2) Suppressing the erosion of lining (MgO-C brick) and accelerating reduction of chrome ore can be satisfied, at the same time, by controlling the slag composition ( (%MgO+%Al2O3) : 4647%).
( 3 ) The method for using fine chrome ore without agglomeration was devised.
( 4 ) The composition of product is lower in S and Si, higher in C and Cr (about 1%), than conventional EF product.
P content of the product depends mainly on the carbonaceous materials used. As the process for producing low P ferrochrome with cheap carbonaceous materials ( e.g. green oil coke), a process composed of rotary kiln and smelting reduction furnace was proposed.
Compared with conventional EF process, the advantages of this process are low energy cost, direct use of fine ore and low impurity in product.
This process can be applied for the production of other metals and alloys.