ABSTRACT
The livestock greenhouse gas (GHG) emission was mainly from anaerobic digestion of manure and wastewater. Traditional anaerobic digestion is liquid anaerobic digestion using high water content feedstocks such as wastewater and slurry. The most widespread piggery waste-water treatment system in Taiwan is the three-step piggery waste-water treatment system, which includes the stages of solid/liquid separation, anaerobic digestion and activated sludge treatment. The emission factors of GHG were calculated from the data of analyzed on-site samples, taken from the gas outlets of the selected anaerobic piggery wastewater treatment facilities prior to pressure stabilizers in northern, central and southern pig farms. A preliminary study was performed in an acrylic anaerobic digester with fresh cattle manure as the sole feedstock. The anaerobic digestion basin is a plug-flow, top-opened, horizontal and underground waste-water basin covered with a plastic lid and constant pressure device: biogas can be collected from the top of the plastic cover.
