A technology review on treatment of acid mine drainage with bentonite\u2013steel slag composite

Abstract

Acid mine drainage (AMD) which produced in the process of mining seriously pollutes the water resources and endangers the ecological environment due to its physicochemical characteristics, such as low pH, high salinity and high heavy metal concentrations. In recent decades, the treatment of AMD has become a key issue in the field of environmental protection. One important method of AMD treatment is adsorption method, and the selection of adsorbent is the key of this technique. Bentonite and steel slag are usually sintered at high temperatures to prepare bentonite–steel slag composite. AMD treatment with bentonite–steel slag composite, as a new adsorbent, is emerging as a promising treatment method by physical adsorption, ion exchange and chemical neutralization. The bentonite–steel slag composites mainly include bicomponent composite with bentonite–steel slag and multicomponent composite with bentonite–steel slag modifier. The author found that this important research question was rarely paid attention to, therefore, and the author combined with previous research and theories to promote the explanation of this problem. In this review, the technology of treatment of AMD with bentonite–steel slag composite is comprehensively discussed. Also, the role of its mechanism is also discussed in-depth. This paper provides a scientific reference on the remediation of contaminated environments.