Characterization of Adansonia Digitata Seed Cake with a View to Identifying an Energy Recovery Strategy

Agri-food processing emits huge quantities of waste and is considered one of today's major environmental problems. There are many different options (anaerobic digestion, thermochemistry and feed production) that can be applied to the management and evaluation of waste treatment. The aim of the present study was to explore the appropriate recovery option for Adansonia digitata seed cake through its characterization. The physicochemical characteristics of Adansonia digitata seed cakes were determined in accordance with international standards. Anaerobic digestion was tested under thermophilic conditions in batch mode over 75 days. Results showed that dry matter content averaged 87.35 ± 0.03%, organic matter content averaged 95.03 ± 0.41%, carbon to nitrogen ratio averaged 19.75. Digestion of Adansonia digitata seed cakes proved highly productive, with a maximum percentage of 68.5% CH 4 for 185.57 liters of biogas, i.e. an average production of 2.47 liters per day for 1720 g DM. The methanogenic potential (BMP) of Adansonia digitata seed cake was 331.21 ml/g of organic matter introduced. Adansonia digitata oilcake had an average gross calorific value of 18.54MJ/Kg. These results are encouraging and mark the start of any study on the energy recovery of Adansonia digitata seed cake in biogas.