Research on zinc extraction, sintering, and tuyere reinjection are ongoing, but what are its present industrial uses? (from Bangladeshi Steel mills, they are bought for about 0.3-0.4 $/kg)
Iron Blast Furnace Dust is mainly Iron Oxides rich in carbon and is recycled in Iron Sinter-making. This Iron Sinter can be charged in to Blast furnace again.
Due to the high content of Zn, and other metals, such as In and Mn, in the iron blast furnace dust, I think the key is to recovery the valuable metals in the dust. You can find some researches in this field.