Bio-drying of green waste with high moisture content

In this study, the effect of bio-drying process on green waste was investigated. Four different sets of bio-drying processes were conducted and the impact of bulking agent (BA) evaluated. The laboratory experiment consisted of a 0.8 m3 bio-drying reactor equipped with a matrix temperature measuring and air supply system. A 50 kg of green waste was placed in the reactor with an uninterrupted airflow rate of 0.3 m3/kg h. The results obtained indicated that the bio-drying process reduced the moisture content (MC) of waste with BA by 27% more than green waste alone after 7 days. Thus, allowing the production of bio-dried waste with a net calorific value of 6265 kJ/kg wet weight, 54% higher than its initial value with 37% decrease in weight in the original mass of the waste. Although on the average, bio-drying of green waste alone showed significant reduction in volume (87%), weight (54%) and increase in calorific value (118%), bio-dried matrix with BA was the most preferred option since the process produced no leachate and generated the highest calorific value.