EVAPORATION LOSS OF AMMONIUM-NITRATE PARTICLES DURING FILTER SAMPLING

This study examines the evaporation loss of submicron. monodisperse am monium nitrate particles during filter sampling when the upstream satu ration ratio is zero. The proposed model has considered the upstream p article concentration, the porosity of the particle bed, particle diam eter, upstream temperature, pressure drop. According to the present re sults, upstream particle concentration heavily influences the evaporat ion loss of ammonium nitrate particles. Theoretical results agree reas onably well with the experimental data obtained in the laboratory unde r well-controlled conditions. Results presented herein confirm that th e simplified theory by Zhang and McMurry (1992) provides a reasonable yet somewhat lower collection efficiency of volatile species during fi lter sampling owing to the assumptions in the downstream saturation ra tio and pressure drop. (C) 1997 Elsevier Science Ltd. All rights reser ved.