Aerosol Penetration Through Transport Lines

Abstract

It is very important to minimize the losses in aerosol transport systems for the Continuous Air Monitors (CAM) to have a prompt and a meaningful alarm and the U.S. Environmental Protection Agency (EPA) also Currently mandates continuous emissions monitoring (CEM) for those stacks and ducts of nuclear industry that can potentially emit significant quantities of radionuclides. Tile EPA has also recently given the U.S Department of Energy (DOE) permission to use Alternate Reference Methodology (ARM) at its facilities. Under the ARM, losses of aerosol particles in the transport lines must be evaluated LISillcy the DEPOSITION software. The U.S. Nuclear Regulatory Comission [sic] also states DEPOSITION code as an alternative method to evaluate losses in a sampling line. The purpose of this study was to develop a Windows version of the DEPOSITION code. The Windows version is expected to be more user friendly, through the use of pull down menus and dialog boxes . The new version also includes models to predict aerosol penetration thrush shrouded probes and transition fitting('s. Experimnents were carried Out to validate the code. The experiments were carried out for different flow rates for a particle size of IO lam aerodynamic diameter (AD). The penetration of aerosol particles through the transport line initially increased with the increase in flow rate and it was maximum for a flow rate of I? 1. 7 L/min (85.2%) and then it showed a decreasing trend similar to DEPOSITION predictions. Experiments for prediction of aerosol penetration through transport system was done component wise for two different flow rates, 27.5 L/min, and, 18 1.1 L/min. For 27.5 L/min, the experimental results and DEPOSITION predictions for the total penetration were 71.6% and 78.3%, respectively, and, for 18 1.1 L/min, the experimental results and DEPOSITION predictions were 81.7% and 72.5 %, respectively.