*Furnace Type (spray roaster, fluidised bed or combined furnace)
*Physical Properties of Iron Oxide By-Product (ferric oxide powder or pellets)
*Purity and commercial value of Iron Oxide By-Product
**Cl content
**SiO content (typically 40 to 1000 ppm)
**other impurities
**specific weight (typically 0.3 to 4 kg per litre)
**specific surface (typically 0.01 to 8 m2/g)
*Energy Consumption (between 600 and 1200 kcal/L)
*Fuel type
*Concentration of regenerated acid (typically approx. 18% wt/wt)
*Purity of regenerated acid (remaining Fe content, Cl content)
*Recovery efficiency (typically 99%)
*Rinse water utilization
*Stack emissions (HCl, Cl, Dust, CO, NOx)
*Liquid effluents (composition, amount)