Plant ash augmented enzymatic hydrolysis approach for ultrafast conversion of food waste to biofertilizers

• Main Author: Tan, Tiffany Rou Jie
• Other Authors: Liu Yu
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2022
• Subjects: Engineering::Environmental engineering::Waste management
• Online Access: https://hdl.handle.net/10356/157926
• Institution: Nanyang Technological University

This study developed an augmentation approach of the enzymatic hydrolysis of food waste using plant ash with the fungal mash produced in situ from food waste as well. The mixture of food waste, fungal mash and different concentrations of plant ash were prepared for hydrolysis. After the 8-h hydrolysis, the hydrolysate solid and liquid were separated. The results show that the NPK contents in both produced hydrolysate solid and liquid can meet the requirements for biofertilizer. To find out the suitable concentration of plant ash that provides the most favourable results, a field planting trial was carried out using a commonly consumed leafy vegetable, xiao bai cai (Brassica rapa), by the addition of food waste-derived biofertilizers in place of commercial biofertilizers. The results of the field planting trial show that the biofertilizers produced with augmentation of 15% and 30% plant ash (w/w food waste) provided results that are comparable to the growth of xiao bai cai from commercial biofertilizers. As such, it is suggested that hydrolysis of food waste with 15% or 30% plant ash (w/w food waste) and the fungal mash produced in situ from food waste could produce biofertilizers which favour the growth of plants. Hence, this may be another option in food waste management to achieve the ultimate target of zero waste discharge.