A designed moderately thermophilic consortia with a better performance for leaching high grade fine lead-zinc sulfide ore. (1st February 2022)

• Record Type: Journal Article
• Authors: Zhou, Siyu; Liao, Xiaojian; Li, Shoupeng; Fang, Xiaodi; Guan, Zhijie; Ye, Maoyou; Sun, Shuiyu
• Is Part Of: Journal of environmental management. Volume 303(2022)
• Publication Date: 2022-02-01
• Subjects: Bioleaching -- Fine particle size raw ore -- EPS fraction -- Sulfobacillus benefaciens; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2021.114192
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Unwieldy fine sulfide ores are produced during mining; without being appropriately disposed of, they can cause environmental pollution and waste resources. This study investigated the leaching performance of a moderately thermophilic consortia ( Leptospirillum ferriphilum + Acidithiobacillus caldus + Sulfobacillus benefaciens ) for fine lead-zinc sulfide raw ore. The results showed this microbial community created a low pH, high ORP, and high cell concentration environment for mineral leaching, improving bioleaching efficiency. Under the action of this consortia, the zinc leaching rate reached 96.44 in 8 days, and reached 100% after 12 days. EPS analysis indicated that the consortia could mediate the secretion of more polysaccharides to ensure leaching efficiency. EPS levels and amino acids were the main factors affecting bioleaching. An analysis of mineral surface characteristics showed the consortia effectively leached pyrite and sphalerite from the fine sulfide ore, and prevented the mineral surface forming the jarosite that could hinder bioleaching. This study found that bioleaching reduced the potential environmental toxicity of the minerals, providing an important reference for guiding the bioleaching of unwieldy fine sulfide raw ore. Highlights: A designed moderately thermophilic consortia performance on fine lead-zinc sulfide raw ore bioleaching was studied. Bioleaching efficiency of zinc reached to 96.44% in 8 days, as well as nearly 100% in 12 days. Consortia mainly affected the bioleaching process by polysaccharides, EPS content and amino acids. Bioleaching could greatly reduce potential heavy metals pollution of the minerals.