CHEMICAL CHARACTERIZATION OF EXHAUST EMISSIONS ORIGINATING FROM THE REGENERATION MODE OF A DIESEL PARTICULATE TRAP

The chemical characterization of exhaust emissions originating from th e regeneration mode of a diesel particulate trap was achieved. The reg eneration process was carried out by heating the particulate trap to 7 00-degrees-C for 208 min with an air stream passing through. Emissions of carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO(x)), particulates, chemical compounds present in the particulate and the se mi-volatile phase were identified and quantified. The n-alkanes with c arbon number ranging from C15 to C35, 15 polycyclic aromatic hydrocarb ons (PAH) and 1-nitropyrene have been identified. Results obtained for a full regeneration mode were: CO, 200 mg; HC, 30 mg; NO(x), 500 mg; particulates, 5.5 mg; aliphatic hydrocarbons, 90 mug; sum of 22 PAH, < 3 mug and 1-nitropyrene, < 0.02 mug respectively. A white residue obt ained in the sampling device was identified as calcium sulfate hydrate . The emission factors determined show that the amount of pollutants e mitted during the regeneration mode is negligible compared to emission s during the accumulation mode.