Photobioreactor systems for mitigating ammonia and carbon dioxide from a broiler house

Abstract

This study investigated the effectiveness of photobioreactor (PBR) systems in reducing air pollutants emitted from broiler houses. It focused on two microalgae species and one cyanobacteria grown under different media conditions and investigated their ability to mitigate ammonia (NH₃) and carbon dioxide (CO₂) in the exhaust air of a broiler house. Ankistrodesmus sp. achieved the highest cell concentrations across all experiments, with maximum dry biomass concentration observed under Nitrogen-free Bold's Basal Medium (BBM-N) culture condition. Scenedesmus sp. showed the highest NH₃ mitigation efficiency (52.3%) with BBM-N culture, while Synechococcaceae species exhibited the highest CO₂ mitigation efficiency (70.8%) with DI-water culture condition. Operating costs for producing 1.0 g L^-1day^-1 of dry microalgal biomass ranged from 0.10 to 0.35 USD L^-1day^-1. The cost of removing 1 g of NH₃ ranged from $3.53-7.16, while for CO₂, it ranged from $0.04-0.59. The study also evaluated the economic feasibility of this approach, demonstrating significant cost savings in biomass and protein production. These findings highlight the potential of PBR systems as a sustainable solution for reducing air pollutants in broiler house environments.

Keywords: Air emissions; Biomass; Microalgae scrubber; Mitigation; Nutrient recovery; Photobioreactor.