EFFECTS OF BIOCHAR ON POULTRY WASTE COMPOSTING UNDER THE AEROBIC CONDITION

Abstract

To investigate poultry-waste-composting, one pilot-scale experiment was carried out to produce good quality compost using poultry litter (PL) and different bulking agents such as biochar, rice straw (RS), rice husk ash (RHA) and tea waste (TW). For this experiment, 0.733 m3 each of six square-shaped bins were used with dimensions, 0.95 m long, 0.93 m wide and 0.83 m height . The study was conducted at the Research Field of Department of Crop Physiology and Ecology, Hajee Mohammad Danesh Science and Technology University, Dinajpur, Bangladesh from January to April, 2019. To monitor the composting process and evaluate compost quality, some physicochemical parameters such as temperature, moisture content, pH, electrical conductivity, organic matter, volatile solids, total solid, total organic carbon, total nitrogen, total phosphorus and potassium were measured at different phases composting. The composting period lasted 90−100 days. Experimental results showed that the final products had excellent physicochemical attributes (Carbon and nitrogen ratio, C/N: 17.26-22.41, germination index (GI): 119.18-137.77%, total kjeldahl nitrogen, TKN: 0.97-1.38%, organic matter, OM: 35.22-44.3%, total organic carbon, TOC: 20.42-25.69%, pH: 7.05-8.12, EC: 4739- 6456 µS/cm. There was no signicant impact occurred due to using of biochar in this experiment. To achieve good quality compost, poultry litter was used on higher amount with bulking agent (RHA, TW and biochar) where the ratios was (65:15:10:10). The amount (volume of humidifying agents) and time (frequency) of moisture addition also played an important role during composting. Poultry litter produced a high quality soil amender having no phytotoxicity. Nevertheless, composting duration and bulking agents and their ratios are crucial factors that determine the quality of the final product. A full-scale compost unit was designedbased on the experimental results. For a typical small-sized poultry farm, having 1500-2000 number of poultry birds, a total area of about 10 m2 is needed to compost the entire annual produced poultry waste