Vitor, G.Palma, T. C.Vieira, BernardeteLourenço, J. P.Barros, R. J.Costa, Maria Clara2016-02-252016-02-2520150892-6875AUT: JLO01215;http://hdl.handle.net/10400.1/7752Acid mine drainage (AMD) generation is a widespread environmental problem in Europe, including Portugal. Previous experience has shown that a combined process consisting of an anaerobic sulphate-reducing bioreactor, following neutralization with calcite tailing, produces water complying with legal irrigation requirements from synthetic AMD. Aiming the treatment of real AMD a new bioreactor was inoculated with a SRB enrichment obtained from sludge from a local WWTP anaerobic lagoon. In the initial batch phase, sulphate supplementation was needed to achieve high sulphate-reducing bacteria counts before continuous feeding of AMD was started. The system quickly achieved good performance, proving it is easy to start-up. However, this time the neutralization step failed to keep bioreactor affluent pH higher than 5 for longer than three weeks. This was due to armouring of calcite by precipitates of various metals present in AMD. A new configuration, replacing a packed-bed column by a shallow contact basin, proved to be more robust, avoiding clogging, short-circuiting and providing long-term neutralization. The treated effluent, with excess of biologically generated sulphide, was successfully used to synthesize zinc sulphide nanoparticles, both in pure form and as a ZnS/TiO2 nanocomposite, thus proving the feasibility of coupling an AMD bioremediation system with the synthesis of metal sulphide nanoparticles and nanocomposites.engBioremediationAcid mine drainageSulphate-reducing bacteriaZnS nanoparticlesZnS/TiO2 nanocompositesjournal articlehttps//dx.doi.org/10.1016/j.mineng.2014.003