The scarcity of energy resources and the high livestock mortality rates are perpetual problems for small farmers of the Brazilian semi-arid region. From September 2006 to April 2007 a continuous reactor, of 33 m³ with gasometer in PVC flexible film, was installed at the EBDA Experimental Station, Jaguarari, Bahia State and the affluent and effluent biochemical, microbiological, and parasitological characteristics were monitored, the biogas production and composition being evaluated, as well as the use of the biofertilizer in elephant grass. With adequate management, the pollution power of residues reduced significantly. Microbiologically, the efficiency of total and fecal coliforms remotion was above 98%, when the main endoparasite eggs were eliminated after treatment. The biogas production was 0.061 m³ kg-1 of manure. The biogas showed in its composition basically 58 and 34% of methane and carbonic dioxide, respectively. The biofertilizer (pH 7.5) was a great source of nutrients, mainly nitrogen (64 g 100L-1, 80% ammoniacal form) and potassium (214 g 100L-1), increasing forage production, without significant changes in the chemical composition, "in vitro" dry matter digestibility, and mineral content.
biofertilizer; biogas; renewable energy; manure
