NO2 Dispersion Model Of Emissions Of A 20 kWe Biomass Gasifier

Abstract

Biomass valorization represents a simple way to reduce Green House Gases emissions. However, the biomass-to-energy field is limited by high gaseous emission concentrations. Innovative abatement technologies can make gaseous emissions close to zero. In this work, three different NO2 abatement technologies were assessed and compared. A deterministic approach was used to estimate NO2 concentrations using experimental concentrations at the chimney for a 20 kWe biomass gasifier. The gasifier chimney was described as an equivalent stack. The pollutant propagation was simulated with a Gaussian plume dispersion model. On this purpose, the unknown equivalent stack flow rate in the model was adjusted using the available data of NO2 on the ground, considering the changing of the air stability between nighttime and daytime and the variable wind direction. Thanks to pollutants dispersion modeling, the evaluation of the optimal abatement technology was possible, investigating the potential effect produced on people and the environment. Results show a bioscrubber technology as the best one to reduce NO2 concentrations at 100, 1000, 3000 m from the emission point of 74, 75, 70 %, respectively.