Waste valorization through anaerobic co-digestion in coffee and swine farms: CH4 yield optimization and farm-scale viability

Author(s)

Lourenco, Vitor Alves ; Camargo, Franciele Pereira ; Sakamoto, Isabel Kimiko ; Silva, Edson Luiz ; Varesche, Maria Bernadete Amancio

• Document type: Journal article
• Source: Bioresource Technology; v. 415, p. 10-pg., 2024-11-01.

Abstract

Considering that the Brazilian southeast has several agricultural farms that produce coffee and raise swine, and that the waste generated in these farms has some complementary characteristics, the present study aimed to optimize the methane (CH4) yield in the batch anaerobic co-digestion of liquid swine manure (LSM), coffee wastewater (CFW), and coffee husk and pulp. The optimization occurred through a two-factor central composite rotational design with a variation of CFW percentage (8 to 22 %) in the mixing liquid substrates and the organic matter concentration (0.3 to 12 gCOD L-1). The optimized condition had an ideal nutritional condition (14 % of CFW, 86 % of LSM, 7.3 gCOD L-1 and COD/N ratio of 35) to obtain high CH4 production (971.7 mLCH4), yield (160.9 mLCH4 g-1VS), maximum specific production rate (1.6 mL h- 1) and low lag phase (217.6 h). (AU)

• FAPESP's process: 21/10685-7 - Influence of C/N ratio and nutritional conditions of anaerobic co-digestion of swine manure and coffee industry residues
• Grantee: Vitor Alves Lourenço
• Support Opportunities: Scholarships in Brazil - Doctorate