T. Vu Duc

In-stack dilution technique for the sampling of polycyclic organic compounds. Application to effluents of a domestic waste incineration plant

Abstract A dilution technique for on-site stack sampling is described. The procedure enables the effluents to be cooled from 250°C to nearly ambient temperature with nitrogen or air and to circumvent the problems resulting from the handling of dirty stack gases providing dry samples of particulate matter collected on filters. The equipment includes devices to trap the vapor phases of polycyclic aromatic hydrocarbons at −80°C. Low vapor pressure 6-ring PAHs are not detected in both vapor and paniculate phases. 4- and 5-ring PAHs from waste incineration plants are released predominantly in the vapor phase and are not captured by electrostatic filters. These observations raise the problem of their removal. As sources of PAHs, the contribution of the waste incineration plants is in the ng m−3 effluent level.

Characteristics of motor exhausts in an underground car park: Mass size distribution and concentration levels of particles

Abstract The size distribution of car exhaust pollutants have been determined in a confined atmosphere with high‐volume cascade impactor. Lead, C, manganese and polycyclic aromatic hydrocarbons (PAH) collected on filters resulted in the following distribution: 60% of the Pb and Cd were found in particles of submicrometer aerodynamic diameter whilst more than 80% of the PAH were found to be absorbed on particles smaller than 1.1 μm. Mn exhibits an opposite trend being observed predominantly in coarse particles. The characteristics of the indoor exhaust aerosol were compared to those observed in the general environment and at the emission source. Concentration levels were determined in order to assess the public and occupational health aspects. Correlation between Pb, carbon monoxyde and PAH are revealing of a motor exhaust gas source.