From bamboo to biochar: a critical review of bamboo pyrolysis conditions and products with a focus on relevance to the developing world

Abstract

This innovative study explores the production of biochar from the pyrolysis of bamboo, critically analysing various pyrolysis methods with a particular focus on potential separation methods for the resulting syngas mixture, which includes condensable (bio-oil) and non-condensable gases. The effects of pyrolysis conditions on product yield and composition are examined, aiming to maximise biochar yield while minimising greenhouse gas emissions. The study applies the concept of slow pyrolysis to a real-world scenario at Elpitiya Plantation in Sri Lanka, evaluating different process options. The potential benefits of biochar application for improving local soil health and mitigating greenhouse gas emissions are also discussed. For the designed system, an operating temperature range of 250–300 °C was selected to achieve a biochar production rate of 1000 kg per day, processing 2080 kg per day of bamboo feedstock. The resulting syngas mixture is directed through a condenser operating at 90 °C, yielding 538 kg per day of bio-oil and 918 kg per day of combustible gases, which are flared to generate 18.41 kW per day of energy.