Combustible biofuel made from the excrement of chickens, turkeys and other poultry has the potential to replace around 10% of coal-generated electricity, according to a new study authored by Prof. Amit Gross and PhD candidate Vivian Mau from the Zuckerberg Institute for Water Research at Ben-Gurion University of the Negev (BGU) in Israel.
"Environmentally safe disposal of poultry excrement has become a significant problem," the researchers say. "Converting poultry waste to solid fuel, a less resource-intensive, renewable energy source is an environmentally superior alternative that also reduces reliance on fossil fuels."
Researchers were set on finding a method to treat poultry excrement for combustion that worked efficiently and, as a result, helping the environment by reducing dependence on fossil fuels. The waste was treated using two formulas for the creation of combustible biomass fuels. The first, hydrochar, involves heating the wet excrement to temperatures of up to 250°C under pressure, a process known as hydrothermal carbonization (HTC). The second is called biochar, and in it the biomass is slow heated at a temperature of 450°C (842°F) in an oxygen-free furnace.
“We found that poultry waste processed as hydrochar produced 24 percent higher net energy generation," said Prof. Amit Gross, chair of the Department of Environmental Hydrology and Microbiology at BGU's Zuckerberg Institute, in a statement. “Poultry waste hydrochar generates heat at high temperatures and combusts in a similar manner to coal, an important factor in replacing it as a renewable energy source."
The study also showed a significant reduction in emissions of methane (CH₄) and ammonia (NH₃) and an increase of carbon dioxide and carbon monoxide as a result of the HTC process being conducted at higher temperatures.
“This investigation helped in bridging the gap between hydrochar being considered as a potential energy source toward the development of an alternative renewable fuel," Gross said. “Our findings could help significantly reduce greenhouse gas emissions associated with electricity generation and agricultural wastes."
The study was made possible through funding from the Israeli Ministry of Environmental Protection, the Rosenzweig-Coopersmith Foundation, the Israeli Ministry of National Infrastructures, Energy and Water Resources, the Rieger Foundation and the Zuckerberg Scholarship Fund at BGU's Zuckerberg Institute for Water Research.
Read about this news on the international press here and here.