Can Tho, Vietnam—The Southeast Asian Regional Center for Graduate Study and Research in Agriculture (SEARCA), through the Rice Straw Biogas Hub (RSBH) project team, convened on 15 May 2024 with biogas experts for the potential international upscaling of a biodigester machine widely implemented in Vietnam.
The seven-member SEARCA delegation visited Can Tho University to learn more about the Sustainable Biogas Production from Waste Straw (SubProM) biodigester model and discuss its potential replication and use in the Philippines.
Dr. Nguyen Van Cong, dean of the College of Environment and Natural Resources (CENRes) of Can Tho University, welcomed the delegates and expressed his optimism that all biogas experts at the meeting would exchange and learn from each other. With the pressing worldwide issue of greenhouse gas emissions, he said, "Together, we can work to contribute to society through this meeting."
Before the discussion, the RSBH team introduced their project advocacy on low-emissions rice. Through a video presentation, the harmful effects of leaving and burning rice straw in the fields were explained, particularly the factors contributing to greenhouse gas emissions. The RSBH project aims to convert rice straw residues to biogas and other bioenergy to mitigate climate change and promote low-emissions rice.
Dr. Ngo Thi Thanh Truc, deputy head of the Faculty of Environmental and Resource Economics (FERE) and key resource speaker to the RSBH biogas training sessions, spearheaded the international meeting. SEARCA has awarded Dr. Truc a grant to study the socioeconomic value of the SupProM among farming households in Vietnam.
The SubProM is a biomass digester co-designed by Dr. Tran Sy Nam's team from Can Tho University's CENRes and Dr. Jan Bentzen of Aarhus University, Denmark. It converts agricultural waste, including rice straw and water hyacinth, into methane biogas, which can be used as an alternative to fossil fuels.
Dr. Nam stated that although commercial biogas digesters were already common in Vietnam, their team optimized the design using High Density Polyethylene (HPDE) material, which made the digesters durable and less prone to damage, unlike those made with concrete. The SubProM biogas digester, with an eight-meter-long storage tube, is manure-fed. Still, it could be sustainably fed with nonmanure feedstock, particularly water hyacinth and rice straws, for two months.
The meeting was also attended by biogas companies and stakeholders who were interested in biogas production and digester fabrication, including the Japan International Research Center for Agricultural Sciences (JIRCAS), NANO Entech Co., Ltd, Verdant Biogas BV, Tuan Biogas, Blue Dragon Children's Foundation, and Orlar.
The participants also toured the Biogas Park inside the university. They explored the various biodigester setups and types of feedstocks and learned how biogas digesters should be installed and what not to feed them.
Dr. Cong also shared that they once experimented using human manure in one of the digesters. The university is currently exploring how to fully utilize the gas produced by these digesters. They have assured that the HDPE digesters are being used among rural households in Can Tho to produce biogas for cooking fuel.
Before parting ways, the participants also had the chance to engage with Tuan Biogas, a local materials distributor and fabricator of the HDPE biogas digester setup, which retails for around six million Vietnamese Dong.
The benchmarking activity is part of the RSBH project's goal of enabling an environment to utilize rice-production residue, especially rice straw, and convert it to energy for household or commercial use.
The SEARCA delegation was represented by Dr. Maria Victoria Espaldon, work package 6 study leader; Dr. Luis Victor, Jr., biogas consultant; Ms. Lichelle Dara Carlos, Emerging Innovation for Growth Department (EIGD) project specialist; Engr. Aina Angeline Buan, project coordinator; and, Misses Angeli Gerone Platino and Shielo Pasahol, project associates.
To learn more about the RSBH project, you may visit https://www.searca.org/projects/technical-assistance/rice-straw-biogas-hub or email .
