Numerical Simulation on Particulate Matter Emissions from a Layer House during Summer in Northeast China

Abstract

Particulate matter (PM) emitted from livestock and poultry production contributes to atmospheric aerosol loading, affecting animal health and the surrounding atmospheric environment. However, developing and optimizing remediation technologies require a better understanding of air pollutant concentrations, the emission plumes, and the mechanism of emission. Previous studies have primarily focused on indoor air pollution research, while outdoor research is relatively rare. Field test research is not only costly but also consumes extensive amounts of time. The application of computational fluid dynamics (CFD) technology can save a lot of measurement time and repetitive labor, in order to better understand the diffusion fundamentals and spatial and temporal distribution differences of PM. This study monitored the PM concentrations of different particle sizes inside and outside a layer house with negative pressure ventilation in Northeast China during the summer of 2021. These data were also used to validate the three-dimensional simulation of the PM concentrations inside and outside of the layer house in various scenarios of wind directions at different times by CFD technology. Through correlation analysis, it is found that temperature was positively correlated with PM1 and PM2.5, and relative humidity and wind speed were negatively correlated with PM, which has a greater impact on PM10 and total suspended particulate (TSP). The particle size was proportional to the diffusion distance and diffusion height, time, and wind direction both have an impact on the spread of PM. Considering the environmental conditions in Northeast China, increasing the height of the fan by 1 m was suggested to reduce the diffusion of PM concentration. In addition, the diffusion patterns and transport paths in this study provide valuable information for improving control measures to minimize the influence of PM on both animal health and air quality.

Aircraft surveys for air eDNA: probing biodiversity in the sky

“…The vertebrate and enteric bacterial DNA we detected likely originates from animal production facilities, fertilized plots, landfills, or wastewater treatment plants found throughout our study area, and perhaps from hospitals and other facilities that aerate biological waste ( File S1 ). Our flights were positioned over hypothesized DNA aerosolization sources ( e.g ., poultry houses, which constitute a primary driver of the local economy), where cooling fans and mechanically ventilated exhaust systems are used to increase ventilation and remove excess heat, presumably leading to higher DNA emissions ( Guo et al, 2020 ; Zhang et al, 2022 ). Our results point to the importance of monitoring agricultural bioaerosols, as poultry manure, litter, feather fragments, skin, microbiota, and related bioaerosols are associated with adverse environmental and health impacts, including acute and chronic respiratory disorders ( Oppliger et al, 2008 ; Viegas et al, 2013 ).…”