Abstract

DROPPELMANN, Carmen Verónica; GAETE, Carolina Pía  and  MIRANDA, Paulina. Vermicomposting of biological sludge for coliforms reduction. Rev.fac.ing.univ. Antioquia [online]. 2009, n.49, pp.124-128. ISSN 0120-6230.

The aim of the present study was to investigate the effect of stoking density on the pathogens reduction, through the sludge vermicomposting, using the most probable number of fecal coliforms as indicator. The sludge used was generated at an extended aeration system; the stoking density was investigated at 0.2, 0.1 and 0.05 kg-worms/kg-sludge plus a control without worms. At the second day of experimentation the 0.1 kg/kg density achieved a significantly higher removal than the 0.2 kg/kg density. In the same day, all the stoking densities achieved the United States Environment Agency class B sludge standards. Between the 13 and 20 day all the stoking densities, with the exception of the control, achieved the USEPA class A standards. On day 20 the removal in the two biggest stoking densities was 100%.

Keywords : fecal coliforms; sludge; vermicomposting; pathogens reduction.