Dewatering tailings: rapid water recovery by use of centrifuges

Abstract

At present, most tailings are dewatered by static settling in tailings dams. The environmental impact of these large settlings ponds is very dramatic, not to mention the space requirements and the potential risk of dam failure. This method of disposal also results in the loss of process water due to evaporation. This can be significant in areas where the supply of fresh water is limited.The high centrifugal force in a decanter centrifuge drastically increases dewatering efficiency, as centrifugal separation happens at up to 29,430 m/s² (3,000 × gravitational acceleration or g).Depending on the material, more than 90% of the process water can be recovered using centrifuge technology. It can be reused in the mineral processing operation and will increase the water efficiency of the whole mining community. This paper presents the results of actual projects in Brazil and Peru.

Towards a Circular Economy in the Mining Industry: Possible Solutions for Water Recovery through Advanced Mineral Tailings Dewatering

“…Nowadays, centrifugal forces of 29,420 m/s 2 (3000× g) are commonly used to dewater various types of sludge. With centrifuge technology, over 90% of the process water can be recovered, making it suitable for reuse in mineral processing operations and significantly improving water efficiency within the mining community [134,135].…”

Practical tailings slurry dewatering and tailings management strategies for small and medium mines

“…The decantation process is assisted by shaping the centrifuge barrel conically at the solids discharge end. A typical centrifuge arrangement is shown in Figure 3, which is reproduced from Klug et al (2018). Challenges to this approach that are steadily being overcome lie in the following:…”

Avaliação de centrífugas Decanter para desaguamento de rejeito do beneficiamento de bauxita.

“…Pode-se perceber que os impactos ambientais, nos quais se enquadram a produção de rejeitos e a disposição dos mesmos, estão em maior número, seguido pelos impactos econômicos. Na indústria da mineração, primeira etapa no processo de produção de alumínio, a escala de geração de rejeitos pode ser imensa, e seu armazenamento e manuseio podem ser um problema ambiental se não gerenciados de maneira adequada (KLUG, SCHWARZ, 2019). Como consequência, rejeitos são dispostos a úmido todos os anos em barragens de rejeito ou lagoas de disposição, que podem apresentar alto grau de risco e elevado custo de implantação.…”