Heap leaching of gold with in-situ bacterial formation of the leach lixiviant. The case for the bio-formation of (1) cyanide lixiviant, and (2) thiosulfate lixiviant

通过原位细菌形成浸出液来堆浸金。

• 批准号: 523048-2017
• 负责人: Ghahreman, Ahmad
• 金额: $ 3.5万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=719552
• 关键词: Heap; leaching; gold; situ; bacterial; Heap; leaching; gold; situ; bacterial

The conventional method for gold leaching and extraction relies on the use of cyanide (or thiosulfate) as the gold leaching lixiviant. In this process gold from the ore is leached in a cyanide (or highly concentrated thiosulfate) solution, and later is recovered from the solution as impure gold, and finally purified to 99.99% gold.Cyanide is known to be an extremely toxic reagent; however, it is highly selective for gold leaching with very attractive leaching efficiency. Thus the replacement of cyanide with alternative lixiviants is very difficult in the gold industry. Nonetheless, the shipping and handling of cyanide salts to the gold operations have always raised concerns. This proposed project pertains to the development of an alternative route for the in-situ generation of cyanide for gold leaching thus eliminating the use of cyanide as a "purchased-reagent" in the gold industry. Herein, it is proposed to use cyanide producing bacteria in gold heap leaching operations to produce cyanide. The in-situ formation of cyanide in the gold heap leaching operations would eliminate the need for the purchase and shipping of cyanide from the cyanide production facilities to the gold mines sites around the world.As a secondary objective, the proposed research will also investigate the option for the in-situ production of thiosulfate, which is known to be a very attractive lixiviant for gold leaching, similar to cyanide. The challenge with the thiosulfate gold leaching process is the high cost of the thiosulfate reagent (the process requires large volumes of thiosulfate salt for gold leaching). In this research project we will also investigate the possibility of the in-situ thiosulfate production from the sulfide ores in the gold heap leaching operations, thus providing a very low cost lixiviant for gold leaching.

黄金浸出和提取的常规方法依赖于将氰化物（或硫代硫酸盐）用作黄金浸出的利用。在此过程中，来自矿石的黄金在氰化物（或高度浓缩的硫代硫酸盐）溶液中浸出，然后从溶液中回收为不纯黄金，并最终将其纯化至99.99％的黄金。氯化物是一种非常有毒的试剂。但是，它具有非常有吸引力的浸出效率的黄金浸出式高度选择性。因此，在黄金行业中，用另类利克西亚人替代氰化物非常困难。尽管如此，将氰化物盐运送到黄金运营的运输和处理一直引起了人们的关注。 该建议的项目涉及开发氰化物原地氰化物的替代途径，从而消除了在黄金行业中使用氰化物作为“购买的”。 本文中，建议在金堆浸出手术中使用氰化物产生细菌来产生氰化物。金堆浸出操作中氰化物的原位形成将消除从氰化物生产设施购买和运输到世界各地的金矿地点的需求。作为次要目标，拟议的研究还将调查对硫代硫酸盐含有非常有吸引力的利克斯·利克斯（Lixiant for Lixiant for Lixiant for Lixiant for Gold Lixiant）的选择，这是与金liessiant相似的，这是相似的。硫代硫酸盐浸出过程面临的挑战是硫代硫酸盐试剂的高成本（该过程需要大量的硫代硫酸盐盐才能用于黄金浸出）。在该研究项目中，我们还将调查来自金堆浸出操作中硫化物矿石矿石硫酸盐生产的可能性，从而为黄金浸出提供了非常低成本的利用。