Abstract

HERNANDEZ BERRIEL, María del Consuelo et al. Heavy metals in solid waste and leachate in bioreactors at different recirculation rates. Rev. Int. Contam. Ambient [online]. 2012, vol.28, suppl.1, pp.79-84. ISSN 0188-4999.

Heavy metals (MP) are part of the pollutants contained in the leachate, which is generated by the decomposition of municipal solid wastes (RSU), which it by toxicity causing severe problems to the environment. The objective of this study was to determinate the effect of different rates of leachate recirculation in the concentration of MP, and in the waste of the matrix of anaerobic bioreactors (BrA) at laboratory scale, to determinate the rate that produced a minor leaching of MP. There were used 20 BrA with RSU from landfill of Patzcuaro, Michoacan, Mexico; four as controls, and for the other 16, its leachates were recirculated twice a week in order to keep the moisture contents of 50, 60, 70, 80% wet basis (% Hbh) by quadruplicate. The leachates that were produced were followed for 126 days, and pH and total heavy metals (MPT) were determined. pH, organic matter (MO), MPT and available heavy metals (MPD), Ni, Pb and Zn were determined in solid discharges wastes. On the other hand, the leachate generated at 80 and 70% Hbh showed less lixiviation of HM, whereas 50% Hbh during hydrolysis and acidogenic phases showed high concentrations of HM. For MPT in solid waste, Ni and Pb, they showed significant differences among the samples, and regarding to the MPD, there were only significant differences in Zn. The solid waste recycling of all rates can be used as soil amendments for its high content of MO and low metal concentration.

Keywords : anaerobic biodigestion; metals; treatment of leachate.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )