Study on treatment of acid mine drainage by nano zero-valent iron synergistic with SRB immobilized particles

Abstract

In view of the serious pollution and high cost of treatment of acid mine drainage (AMD) in coal mine, the polyving akohol (PVA) and boric acid embedding cross-linking method was used to prepare the immobilized particles for treatment of AMD with sulfate-reducing bacteria (SRB) and nano zero-valent iron (nano-Fe⁰) as the main body. In order to explore the specification and dosage of each matrix component of immobilized particle, a series of single factor tests and orthogonal tests were carried out to determine the optimal ratio of each matrix component. The results shows that when the SRB quality additive percentage was 30%, the nano-Fe⁰ dosage was 4%, the corn cob particle size was 60 mesh and the dosage was 3%, the SO₄^2-, Cr⁶⁺ and Cr³⁺ removal rates were 82.99%, 99.78% and 38.78%, respectively, the TFe and COD release rates were 4.26 mg·L^-1 and 1,033.4 mg·L^-1, respectively, and the pH value was 8.04, and the treatment effect was the best.