The present application relates to a process for the purification of waste materials or industrial by-products, the process comprising the steps of: a) Preparing a composition (C) by blending or mixing waste materials or industrial by-products comprising chlorine (B) with one or more materials comprising heavy metals (HM) b) Reacting (B) and (HM) by thermal treatment of (C) c) Separating evaporated heavy metal chloride compounds (HMCC) d) Obtaining a solid material after the thermal treatment step.

Embodiments of the invention relate to a process for removing fluoride from a solution or suspension containing zinc, in particular a solution of zinc sulfate, a defluoridated solution of zinc sulfate obtainable by such a process, its use as well as processes for producing zinc and hydrogen fluoride or hydrofluoric acid. The process for removing fluoride comprises (i) providing a solution or suspension A containing zinc, wherein the solution or suspension A containing zinc further contains fluoride ions; (ii) adding a solution B containing a dissolved salt of a rare earth element to the solution or suspension A containing zinc, wherein a solid comprising a rare earth element fluoride and a solution C containing zinc are formed; and (iii) separating the solid from the solution C containing zinc, wherein the solution C containing zinc has a lower concentration of fluoride ions than the solution or suspension A containing zinc.

A solvent extraction method for separation and recovery of nickel, cobalt, manganese, and zinc is proposed. More particularly, the present method relates to a solvent extraction method for separation and recovery of nickel, cobalt, manganese, and zinc, the method being capable of separately recovering four kinds of valuable metals as respective monotype metals from a starting material containing nickel, cobalt, manganese, and zinc by involving: a first solvent extraction step in which the starting material is separated into a first aqueous phase solution containing nickel and cobalt and a second aqueous phase solution containing nickel, cobalt, manganese, and zinc; a second solvent extraction step in which nickel (Ni) and cobalt (Co) are separated and recovered; a third solvent extraction in which zinc (Zn) is recovered; and a fourth solvent extraction step in which manganese (Mn) and cobalt (Co) are separated and recovered.

The present application relates to a process for the purification of waste materials or industrial by-products, the process comprising the steps of: a) Preparing a composition (C) by blending or mixing waste materials or industrial by-products comprising chlorine (B) with one or more materials comprising heavy metals (HM) b) Reacting (B) and (HM) by thermal treatment of (C) c) Separating evaporated heavy metal chloride compounds (HMCC) d) Obtaining a solid material after the thermal treatment step.

The present application relates to a process for the purification of waste materials or industrial by-products, the process comprising the steps of: a) Preparing a composition (C) by blending or mixing waste materials or industrial by-products comprising chlorine (B) with one or more materials comprising heavy metals (HM) b) Reacting (B) and (HM) by thermal treatment of (C) c) Separating evaporated heavy metal chloride compounds (HMCC) d) Obtaining a solid material after the thermal treatment step.

The present zinc recovery method is characterized in including a dissolving process of treating a raw material containing zinc with an alkaline fluid at a temperature equal to or higher than 100 C. to dissolve zinc contained in the raw material, and a recovering process of recovering zinc extracted from the raw material by the dissolving process.

Disclosed is a fuming furnace with a lead collecting and discharging function, the fuming furnace comprising a furnace body; the furnace body is provided with a hearth therein and a tuyere thereon; the bottom of the hearth forms a molten pool; the furnace body is further provided with a slag discharging outlet and a lead discharging outlet thereon; the furnace body comprises a furnace bottom water jacket and a hearth water jacket; the furnace bottom water jacket is provided with a refractory brick layer at the inner wall thereof; the refractory brick layer is provided with a lead collecting and discharging channel therein for collecting and discharging lead; the lead collecting and discharging channel is in communication with the lead discharging outlet, and the lead collecting and discharging channel is in communication with the molten pool via joints between the refractory bricks forming the refractory brick layer.

Disclosed is a fuming furnace with a lead collecting and discharging function, the fuming furnace comprising a furnace body; the furnace body is provided with a hearth therein and a tuyere thereon; the bottom of the hearth forms a molten pool; the furnace body is further provided with a slag discharging outlet and a lead discharging outlet thereon; the furnace body comprises a furnace bottom water jacket and a hearth water jacket; the furnace bottom water jacket is provided with a refractory brick layer at the inner wall thereof; the refractory brick layer is provided with a lead collecting and discharging channel therein for collecting and discharging lead; the lead collecting and discharging channel is in communication with the lead discharging outlet, and the lead collecting and discharging channel is in communication with the molten pool via joints between the refractory bricks forming the refractory brick layer.

A method for the treatment of jarosite and other residues of the zinc and lead production industry, including the following steps: thermal treatment of the residues, at a temperature between 500? C. and 700? C., to obtain the evaporation of the imbibition water and the demolition of the jarosite molecule, resulting in the development of SO3 and in the removal of OH.sup.? groups to give additional water in the gaseous phase, and resulting in the obtainment, from the recondensation of these components, of an aqueous solution of diluted sulfuric acid, and with the simultaneous formation of a solid fraction composed of iron(III) oxide, zinc, lead, silver, copper sulphates and other minor elements; and then steps for acid leaching, a refining treatment; and purification to obtain solubilization of iron(III); separation of the solubilized iron(III) from the silica, which remains insolubilized; precipitation of iron(III) to obtain iron oxide pigment.

A system and method for recycling metals from industrial waste using an electrodepositing technique. The method includes the steps of collecting the industrial waste, transporting, processing and digesting the waste in a solvent or acidic solution and then electrodepositing out the desired metals. Other processing steps may be used to prepare the industrial waste for electrodeposition and the process may be repeated on the digest solution, to obtain multiple metals.