Effects of Sodium Carbonate and Calcium Oxide on Roasting Denitrification of Recycled Aluminum Dross with High Nitrogen Content

Abstract

Aluminum dross is solid waste produced by the aluminum industry. It has certain toxicity and needs to be treated innocuously. The effect of sodium carbonate and calcium oxide on the denitrification efficiency of high nitrogen aluminum dross roasting was studied in this paper. By means of XRD, SEM and other characterization methods, the optimum technological parameters for calcination denitrification of the two additives were explored. The test results show that both additives can effectively improve the efficiency of aluminum dross roasting denitrification, and the effect of sodium carbonate is better. When the mass ratio of sodium carbonate to aluminum dross is 0.6, the roasting temperature is 1000 °C and the roasting time is 4 h, the denitrification rate can reach 91.32%.

Optimizing Wet Hydrolysis for Nitrogen Removal and Alumina Recovery from Secondary Aluminium Dross (SAD)

“…Therefore, the first priority in the treatment of SAD should be harmlessness, with denitrification as a potential option [9]. The denitrification of SAD can be achieved through dry roasting or wet hydrolysis [10][11][12][13]. However, dry roasting denitrification demands a high temperature and advanced equipment, whereas wet hydrolysis denitrification requires only low equipment investment and can be easily industrialized [14][15][16].…”