Liquid and solid effluent treatment process

A process for recovering metals such as Ni, Co, Mn, Cu, Zn, among others, through precipitation as sulphides, enabling recovery of magnesium in the form of hydroxide, carbonate and oxide and providing recovery of sulphate as gypsum and ammonium sulphate. Liquid phase, after full treatment, comprises...

Full description

Saved in:
Bibliographic Details
Main Authors SILVA ROBERTO MATTIOLI, EVELIN SALOMAO SOLINO
Format Patent
LanguageEnglish
Published 25.10.2011
Subjects
CHEMISTRY
COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSESC01D OR C01F
INORGANIC CHEMISTRY
METALLURGY
Online AccessGet full text

Cover

More Information
Summary:A process for recovering metals such as Ni, Co, Mn, Cu, Zn, among others, through precipitation as sulphides, enabling recovery of magnesium in the form of hydroxide, carbonate and oxide and providing recovery of sulphate as gypsum and ammonium sulphate. Liquid phase, after full treatment, comprises recovered water with a quality proper for total reuse in industrial process. This process of liquid and solid effluent treatment is provided with flexibility to process several types of effluents presenting wide variations in their chemical composition. The main steps of this process are: (1) equalization of liquid effluent, (2) precipitation of metals as sulphides, (3) oxidation of metallic sulphides and crystallization as metallic sulphates, (4) precipitation of magnesium as hydroxide and calcination thereof into magnesium oxide (5) recovery of ammonia, (6) preconcentration of the remaining saline solution, (7) evaporation/crystallization of ammonium sulphate, (8) storage of recovered water, (9) partial or total precipitation of sulphate contained in the effluent with quicklime, (10) segregated storage of gypsum and gypsum-magnesium mixture, (11) softening of the remaining solution and (12) storage of softening water.
Bibliography:Application Number: US20090351058