摘要 |
<p>A process for the recycling of salt and alkaline batteries of all sizes and types comprises a three stage scheme of sorting, mechanical treatment and hydrometallurgical treatment. A process for the recycling of batteries of all sizes comprises a three stage succession : (a) a primary phase for the sorting of collected batteries ; (b) a second phase of mechanical treatment of the batteries by milling, magnetic separation of the milled product, granular fractionation of the non-ferrous milled material and qualitative separation of the large particles ; 7 fractions are separated designated : ferrous, fines, medium, rebus, non-ferrous, plastics and paper ; (c) a third phase of physical or physico-chemical treatment of the fractions, the ferrous and no-ferrous being valorized and the plastics fraction being washed in H2SO4 and HNO3 and drained. The process is characterized in that, in the third phase the middle fraction is re-milled and integrated with the fine fraction to form a Black Mass group ; this is submitted to a hydrometallurgical treatment comprising the stages : (i) caustic soda wash; (ii) filtration and rinsing to extract chlorides, ammonium, potassium and other soluble salts ; (iii) acid attack by H2SO4 solution in the presence of Fe to dissolve Zn and Mn ; (iv) reduction of the group by H2O2 in the presence of an antifoam agent to dissolve residual Mn ; (v) adjustment of pH by ammonia, ZnO or MnO2 ; (vi) flocculation of the group, allowing separation of a solution rich in sulfates of Zn and Mn; (vii) purification of the solution by adjustment of pH with H2SO4; (viii) cementation of Cu, Cd, Hg, and Pb with Zn powder and elimination by filtration ; (ix) complexation of Ni with sodium or potassium ethylxanthate after pH adjustment and filtration ; and (x) valorization of sulfates of Zn and Mn in solution or after precipitation.</p> |