Stiff vacuum extrusion has been applied for the agglomeration of the iron ore concentrate and fine coal. The products of agglomeration-extrusion briquettes (BREX) were subjected to the high temperature reduction. Under the conditions similar to the ITmk3 process in general. It has been demonstrated that the iron ore and coal BREX could be considered as the alternative to the iron and coal pellets for the high temperature reduction in furnaces like Rotary Hearth Furnace (RHF).

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Industrial stiff vacuum extrusion briquettes (BREX) producing line can efficiently provide for the smallscale blast furnace (BF) operation with 100% briquetted charge. Physical and metallurgical properties of the BREX are being investigated. A new effect of the non-linear strengthening of the BREX bonded with the combined Portland cement and Bentonite binder is described. Application of this combined binder results in the local maximum of the cold compressive strength of the BREX on third day of strengthening. Hot strength mechanism of the BREX is explained and was found to be related with creation of the metallized shell on their surface, sintering of the iron-containing particles and further creation of the metallicc phase surrounded by the silicates and ferrites. The addition of the iron ore fines to the BREX composition can improve their sintering during reduction thus helping to keep the integrity of the agglomerates. Results of the industrial operation of the small-scale BF with BREX are analyzed. The consumption of coke in the BF at 100% of BREX does not exceed 500 kg/t compared with 680 kg/t for the smelting without BREX.KEY WORDS: extrusion briquette (BREX); stiff vacuum extrusion; small-scale blast furnace; coke rate; hot strength.