Method for recovering noble metal from gold and silver converter waste magnesium brick

Abstract

The invention relates to the technical field of noble metal recovery, in particular to a method for recovering noble metal from a gold and silver converter waste magnesium brick. The method comprises the working procedures of grinding a waste magnesium brick sample, performing flotation, performing gravity concentration on flotation tailings, performing flotation, performing gravity concentration, removing magnesium through hydrochloric acid, and the like. The problems that the concentrate cannot be fed into a furnace because of high magnesium content of the concentrate and the recovery rate is high when a gravity concentration method is singly used are solved; the problems that the concentration ratio of the concentrate is not high, the using amount of sulfuric acid is large, and leaching residue is difficultly filtered when a sulfuric acid leaching process is singly used are also solved. The magnesium oxide in the concentrate can be removed to the greatest degree by the method, the high-quality gold and silver concentrate is obtained, the gold recovery rate is more than 99 percent, the silver recovery rate is more than 98 percent, and the removing rate of magnesium oxide can be up to over 98 percent. The recovery rate is obviously higher than that of the other processes, the processing cost is relatively low, and the method is convenient to industrially popularize and use.

Description

technical field [0001] The invention relates to the technical field of chemical precious metal recovery, in particular to a method for recovering precious metals from gold-silver converter waste magnesia bricks. technical background [0002] At present, gold and silver smelting converters are mostly used in the gold and silver smelting process. The inner cavity of the gold and silver smelting converter is made of magnesia bricks. When in use, the inner cavity of the gold and silver smelting converter is in direct contact with the smelting metal liquid. The phenomenon of liquid metal penetration, magnesia bricks are mixed with precious metals such as gold and silver. During the maintenance of the gold and silver smelting converter, the waste magnesia bricks will be dismantled and replaced, and the precious metals inside the waste magnesia bricks are mainly recovered by gravity separation and sulfuric acid leaching. The above method has the following problems: 1, when adoptin...

AI Technical Summary

Problems solved by technology

The above method has the following problems: 1, when adopting the gravity separation method, equipment such as shaking tables and spiral chutes are generally used to sort according to the difference in proportion between the minerals and the gangue, and the content of magnesium oxide in the concentrate that is sorted out is still low. Accounting for about 45% of the total weight, it cannot be directly put into the furnace, which seriously affects the recovery rate of gold and silver, which is only about 80%

2. Using the sulfuric acid leaching method, the magnesium oxide in the waste magnesia bricks is chemically reacted to form magnesium sulfate and dissolved in the solution. Although the content of magnesium oxide can be significantly reduced, the enrichment of gold and silver is low, and some impurities are difficult to leach, and A large amount of sulfuric acid

In addition, silicate colloids are easy to form during the sulfuric acid leaching process, which is difficult to settle and hinders filtration, which affects the normal recovery of gold and silver.