BIOCHEMICAL METHANE POTENTIAL OF CASHEW PEDUNCLE WASTE DISCARDED IN THE FIELD

Abstract

The significant increase in demand for renewable energy sources, together with the commitments made by countries to reduce greenhouse gas emissions, has generated growing interest in the energy use of agro-industrial residues. This search for sustainable alternatives has led to greater consideration of how waste generated in agricultural and industrial production can be transformed into energy, thus contributing to a cleaner and more efficient energy matrix. Within the specific context of cashew farming, an agricultural practice developed in the northeastern region of Brazil, it is observed that the waste of the cashew apple (peduncle)—a part of the plant often discarded in the field—contrasts significantly with the fact that this same peduncle has highly relevant organic content. This discarded material can be converted into biogas through a process known as anaerobic digestion. This type of conversion not only offers environmental advantages but also presents benefits in energy generation and economic contributions that can be quite significant. The research adopts a qualitative and quantitative (hybrid) approach. The following research procedures were employed: bibliographic research, documentary research, and experimental and laboratory research. The general objective of this study is to evaluate the methanogenic yield of cashew peduncles wasted in the field through a Biochemical Methane Potential assay, in order to verify their feasibility as a substrate for biogas production within the environmental, energy, and socioeconomic context of Brazilian cashew farming. The research met its proposed objectives by demonstrating that the cashew peduncle has technical viability for biogas generation, representing an alternative that can increase rural producers’ income and help meet national policies for reducing greenhouse gas emissions.