Resumo

VICENCIO-DE LA ROSA, M.G. et al. Stabilization by co-composting of solids removed from wastewater treatment plant of a cheese factory. Rev. Mex. Ing. Quím [online]. 2015, vol.14, n.1, pp.61-71. ISSN 1665-2738.

A wastewater plant of a dairy industry generates 1.6 tons/month of settleable solids and 650 kg/week of floatable solids, which if not adequately disposed off, can cause serious soil contamination and vector attraction. A composting process for stabilizing residues with high fat content that generate unpleasant odors is presented. Laboratory experiments were carried out for determining the appropriate process parameters and scaled-up for the in situ process. Laboratory tests with cattle manure showed a reduction in the production of malodorous gases in three weeks. The resulting compost complied with national and international standards, and can be used in 1:3 compost:soil ratio for soil improvement. The waste stabilized in situ complied with most parameters established in the Mexican regulation (NOM-FF-109-SCFI-2007), excepting pH (9.6) and electrical conductivity (5 dS/m).

Palavras-chave : co-composting; high grease content residues; dairy cattle manure; compost quality; cost.