Environmental impacts of poultry litter gasification for power generation

The poultry industry generates a large quantity of litter, which consists of a mixture of manure, waste bedding and feathers, and can be used for recovery of energy. Recent studies suggest that gasification is a promising technology for an effective conversion of poultry litter to energy. This paper aims to assess the environmental impacts of generating electricity from the gasification of poultry litter in a small-scale integrated gasification combined cycle (IGCC) plant. Gasification of poultry litter has been simulated with ASPEN Plus® software and life cycle assessment has been used to determine the carbon footprint and primary energy demand of the system. The following life cycle stages have been considered: collection and storage of poultry litter, its gasification, syngas cleaning, production of electricity and co-production of ash as a fertiliser. The carbon footprint and primary energy demand of generating 1 kWh of energy by poultry litter gasification plant are estimated at 42 g CO2 eq./kWh and 0.14 MJ/kWh, respectively. Compared to electricity from fossil fuels, this system has 91%-96% smaller carbon footprint and 98%-99% lower primary energy demand. The energy payback period is estimated at 1.5 years.