Abrégé

The present patent relates to a plant in a regime for the two-stage production of copper sulphate pentahydrate from oxidised copper minerals, with an average content of 20% Cu, with mineral species predominant in copper oxides. The first stage is the formation of a stock solution by agitation-leaching 45% of the mineral to be processed and subsequently concentrating to form the stock solution, and the second stage of the in-plant method is a step of saturating the solution and crystallising the copper sulphate, wherein 55% of the remaining mineral is treated during the saturation process. The crystallisation process is carried out in tanks with a coolant in the jacketed sidewalls thereof and which contain a submerged coil, refrigerated water circulating through all the coils. An interior agitation system generates a circulatory movement of the saturated solution, both vertically and horizontally, the solution undergoing controlled cooling from 80-90°C to a final temperature of 8-12°C, to form suitably sized crystals. When the saturated solution reaches a temperature close to 45°C, the initial generation of the crystals and their growth as the temperature of the solution gradually decreases can be seen.

Classes IPC  ?

• C01G 3/10 - Sulfates
• C22B 15/00 - Obtention du cuivre
• C22B 3/22 - Traitement ou purification de solutions, p.ex. de solutions obtenues par lixiviation par des procédés physiques, p.ex. par filtration, par des moyens magnétiques

Abrégé

The present patent considers a two-stage method for obtaining copper sulphate pentahydrate from oxidised copper minerals with an average content of 20% Cu, wherein the predominant mineralogical species are copper oxides. The first stage of formation of the stock solution is by means of leaching under stirring of 40-50% of the mineral to be processed and the concentration for forming the stock solution. The second stage of the process is the copper sulphate solution saturation and crystallisation stage, wherein 50-60% of the mineral to be processed is processed during the saturation process. The crystallisation process is carried out in ponds with cooling of their jacketed side walls and in the interior thereof by means of a submerged coil, wherethrough chilled water will circulate. The internal stirring system generates a vertical and horizontal circulatory movement of the saturated solution so as to generate the controlled cooling thereof from 80ºC to 100ºC until a final temperature of between 5ºC and 15ºC is reached, to favour the formation of adequately sized crystals. When the saturated solution reaches a temperature of nearly 45ºC, the initial generation of the crystals and their growth can be observed as the temperature gradually decreases.

Classes IPC  ?

• C01G 3/10 - Sulfates
• C22B 15/00 - Obtention du cuivre
• C22B 3/22 - Traitement ou purification de solutions, p.ex. de solutions obtenues par lixiviation par des procédés physiques, p.ex. par filtration, par des moyens magnétiques

Abrégé

2323244). The second step of the method is carried out in a fixed oven, to cause the volatilisation of the products of interest, antimony trioxide and the arsenic trioxide, which separate according to their different condensation temperatures. The temperature of the gases reduces from 450°C to 350°C, separating the antimony trioxide while the arsenic trioxide remains volatile and subsequently solidifies at a gas temperature of 300°C to 90°C. Given the condition that lead oxide does not volatilise at the temperature of the initial process, this compound remains solid inside the oven, being recovered as liquid lead, following reduction with carbon.

Classes IPC  ?

• C22B 1/04 - Grillage à l'air
• C22B 5/02 - Procédés généraux de réduction appliqués aux métaux par voie sèche
• C22B 5/08 - Procédés généraux de réduction appliqués aux métaux par voie sèche par les sulfures; Procédés de réaction par grillage
• C22B 5/16 - Procédés généraux de réduction appliqués aux métaux par voie sèche avec volatilisation ou condensation du métal produit
• C22B 13/02 - Obtention du plomb par voie sèche
• C22B 30/02 - Obtention d'antimoine
• C22B 30/04 - Obtention d'arsenic

Abrégé

2323244). The second step of the in-plant method is carried out in a fixed double-chamber oven, to cause the volatilisation of the products of interest, antimony trioxide and arsenic trioxide, which separate according to their different condensation temperatures. The temperature of the gases reduces from 450°C to 350°C, separating the antimony trioxide first, while the arsenic trioxide remains volatile and subsequently solidifies at a gas temperature of 300°C to 90°C. Given the condition that lead oxide does not volatilise at the temperature of the initial process, this compound remains solid inside the oven, being recovered as liquid lead, following reduction with carbon.

Classes IPC  ?

• C22B 1/04 - Grillage à l'air
• C22B 5/02 - Procédés généraux de réduction appliqués aux métaux par voie sèche
• C22B 5/08 - Procédés généraux de réduction appliqués aux métaux par voie sèche par les sulfures; Procédés de réaction par grillage
• C22B 5/16 - Procédés généraux de réduction appliqués aux métaux par voie sèche avec volatilisation ou condensation du métal produit
• C22B 13/02 - Obtention du plomb par voie sèche
• C22B 30/02 - Obtention d'antimoine
• C22B 30/04 - Obtention d'arsenic