Temperatura e tempo de residência na produção de biochar oriundo de dejetos de galinhas poedeiras

Abstract

Poultry wastes have a large amount of nutrients from the feed and can be reused in agriculture. However for the reuse of this residue it is necessary to stabilize it, avoiding environmental contamination. Among the treatments of this residue the most important are: biodigestion, stabilization ponds, stored slurry and production of biochar. Bio-char is a byproduct from the pyrolysis of organic waste, rich in carbon, which has specific characteristics that make it feasible to use it as a soil conditioner, to improve its chemical, physical and biological properties. The production of biochar has been studied as a method for waste treatment in the agricultural and urban environment. Thus, was aimed with this work to study the effects of temperature and residence time interactions on biochar production from poultry manure. Four pyrolysis temperatures (300, 375, 450 and 525°C) and three residence times (30, 45 and 60 minutes) were tested. The raw material was collected at the ICA-UFMG experimental farm and dried at 105°C ± 2°C for 24 h. The pyrolysis tests were carried out in a muffle furnace where the pyrolysis time was counted when the desired temperature was reached. The yield, pH, electrical conductivity and iodine number were analyzed in the biochars produced. The results showed interactions among the treatments, but the effects were different for each trait analyzed. With increasing temperature and residence time, the biochar yield decreased significantly, reaching lower values in the temperature of 525°C and residence time of 60 minutes.