Anais do Simpósio Latino Americano de Ciências de Alimentos
Anais do 14 SLACA - Simpósio Latino Americano de Ciência de Alimentos

The apple pomace derived from apple juice industry corresponds to 25% of the raw material (fresh fruits) processed. A possible route to convert this by-product into methane-rich biogas, promoting bioenergy recovery, is the anaerobic digestion (AD) technology. This study aimed to estimate the theoretical methane production from the AD of apple pomace, and its potential for bioenergy recovery and avoided greenhouse gases (GHG) emissions. The theoretical methane potential was calculated considering the volume of methane produced per day divided by the Organic Loading Rate (OLR). For this, the procedure consisted in first analyzing the apple pomace’s Chemical Oxygen Demand (COD), thencalculating its OLR and the volume of methane produced, considering an Anaerobic Digestion reactor with a total volume of 40 m³, fed with 10 m³ of apple pomace, considering an average COD removal efficiency of 80%, 0.3 m3 of methane gas (CH4)/kg organic load removed and a Hydraulic Retention Time of 25 days. The apple pomace COD was estimated 80.4 kg O2/m³, resulting in 32.16 kg O2/d (OLR) and a theoretical methane production of 7.72 m³/day. Methane-rich biogas can be used for energy recovery in apple juice industry, generating electricity (25.94 kWh/day) and thermal energy (137.35 MJ/day) in a combined heat and power engine. The electricity produced from biogas can mitigate 1.6 ton CO2/day submitting apple pomace to AD. Beyond, methane is a critical GHG, which global warming potential is 28-fold higher than carbon dioxide, also it can be used up for energy purposes avoiding GHG emissions while promoting the bioeconomy and potentially lowering energy costs. Finally, this study demonstrated the potential of apple pomace’s AD for bioenergy recovery in a biorefinery concept.