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 m(3) 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 m(3)/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. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. Ail rights reserved.