Produção de biogás com dejetos de suínos – efeito de energia líquida e ractopamina da dieta

Abstract

The aim of this study was to evaluate the potential of biogas production from manure of swine fed with diets containing different levels of net energy and ractopamine. The experiment was carried out in a 2x5 factorial arrangement (ractopamine = 0 and 10 ppm, and net energy = 2 300, 2 425, 2 550, 2 675 and 2 800 kcal kg-1). Semi-continuous bench digesters were used at an hidraulic retention time (HRT) of 30 days and daily loads for 90 days. Biogas production was measured weekly; analyzes for pH, ammoniacal nitrogen, alkalinity, total nitrogen and total phosphorus were carried out. The results from monitoring analyses showed that there were no risks of failure of the anaerobic digestion process. There was no interaction between levels of net energy and ractopamine concentration, and there was no effect of ractopamine addition on the biogas production (average of 0.07723 m3 kg-1). There was a linear increase (p< 0.05) for biogas production and volumetric biogas production when net energy in the diets increased. Ractopamine as an additive in the diet for swine does not affect the volumetric biogas potential of the swine manure. Greatest potential for biogas production are obtained from manure from animals fed on higher levels of net energy.