METHOD AND SYSTEM FOR THE PROCESSING OF ZINC-CONTAINING WASTE BY MEANS OF BASIC LYING

摘要

A zinc-containing waste treatment process involves neutralizing (40) part of a used leaching solution, after zinc electrowinning (26), with waste acid to form a zinc-rich hydroxide sludge for recycling (50) to the leaching stage. A zinc-containing waste treatment process comprises (a) alkaline leaching (2) of the waste (8); (b) purification of the leach solution especially by cementation (18); (c) extraction of the zinc especially by electrolysis (26); (d) direct recycling of only a first fraction of the used solution (36) containing dissolved parasitic components (especially chlorides and sulfates); and (e) neutralization (40) of a second fraction of the used solution with waste acid to form a zinc-rich metal hydroxide sludge which is separated (45) and recycled (50) to the leaching stage. An Independent claim is also included for an installation for carrying out the above process.