Biogas production from pistachio (Pistaciavera L.) de-hulling waste

ABSTRACT

Pistachio processing wastes create significant waste management problems unless properly managed. However, there are not well-established methods to manage the waste generated during the processing of pistachios. Anaerobic digestion can be an attractive option not only for the management of pistachio processing wastes but also producing renewable energy in the form of biogas. This study investigated anaerobic digestibility and biogas production potential of pistachio de-hulling waste from wet de-hulling process. Best to our knowledge, this is the first report on biogas production from pistachio de-hulling waste. The results indicated that (1) anaerobic digestion of pistachio de-hulling wastewater, solid waste, and their mixtures in different ratios is possible with varying levels of performance; (2) 1 L of de-hulling wastewater (chemical oxygen demand concentration of 30 g/L) produced 0.7 L of methane; (3) 1 L of de-hulling wastewater and 20 g of pistachio de-hulling solid waste produced 1.25 L of methane; and (4) 1 g of de-hulling solid waste produced 62.6 mL of methane (or 134 mL of biogas).

KEYWORDS:

• Anaerobic
• biogas
• de-hulling
• pistachio
• waste

Acknowledgments

Dr. Eylem Dogan-Subasi, Ebru Sarikaya-Kocak, Bulent Tokatli, and Eray Gur are acknowledged for their contributions to this study.

Funding

This study was funded by Republic of Turkey Small and Medium Enterprises Development Organization (KOSGEB) and conducted a part of consulting project for Teknocev Ltd. Sti.

Additional information

Funding

This study was funded by Republic of Turkey Small and Medium Enterprises Development Organization (KOSGEB) and conducted a part of consulting project for Teknocev Ltd. Sti.