Comprehensive utilisation of blast furnace slag

Figures & data

Figure 1. Blast furnace slag treatment process.

Figure 2. Flow chart of INBA.

Table 1. Comparison of the INBA method and the TYNA method.

Item	The INBA Method	The TYNA Method
Manufacture	The drum filters out the water-quenched slag, which is then conveyed by belt to the product tank and transported by truck	Slag treatment with a high speed mechanical granulation wheel combined with a low speed dewatering drum
Condition of equipment	Water sludge is conveyed by belt Low slag content in roller filtered water Low wear and tear on pumps and pipes	Using a pneumatic hoist without running parts Inefficient inspection
Security	Explosion of high pressure water in contact with molten iron slag Slag disposal systems need to be shut down and dry pits installed to address slag discharge issues	The mechanical granulation wheel enables the TYNA method to process slag with < 40% iron There is no need for a separate dry pit to process the slag discharge in case of accidents
Quality of finished slag	High moisture content of slag Water filtration measures in the product tank are required	Moisture content of slag <10% Can be shipped directly

Table 2. Blast furnace slag treatment process and characteristics.

Recycling methods	Heat recovery rate	Cooling method	advantages	disadvantage	Applied enterprise
Wind quenching method	40–50%	Progressive heat exchange with the medium in the bowl during contact	Small footprint Low pollution	The equipment is complex High investment	Sinosteel Grop, Chongqing Steel Group
Rotary drum method	50–60%	The air flow from the high-pressure fan is exchanged with the slag	Small footprint Low pollution	Loud noise 56High raw material requirements	Second Steelmaking of Bao Steel
Centrifugal granulation method	>80%	Heat exchange with water cooling walls	High processing capacity Low investment	Iron slag separation is difficult High raw material requirements	Sha Steelworks, Liuzhou Steel