Emission Characteristics of the Evaporative Pattern Casting Process
Authors: Gressel, MG; O'Brien, DM; Tenaglia, RD
HERO ID: 1482797
Emissions generated during the evaporative pattern casting (EPC) process were investigated. Airborne . . .
Emissions generated during the evaporative pattern casting (EPC) process were investigated. Airborne emissions, emitted during a laboratory mock up of the EPC process using aluminum and gray iron test pump castings, were trapped in a sampling hood during pouring, cooling, and shake out and analyzed by gas chromatography/mass spectrometry and real time direct reading instruments. A similar experiment was performed with the conventional green sand process for comparison purposes. Carbon-monoxide (630080) emissions were above 1000 parts per million during pouring, cooling, and shake out of the iron castings during the green sand process. These were at least an order of magnitude higher than those measured during the EPC process. Carbon-monoxide emissions were not significantly elevated during aluminum processing for either process. More carbon soot was produced by the EPC process for either metal than by the green sand process. More hydrocarbons were produced by the ECP process than during the green sand process for either metal. The highest hydrocarbon emissions occurred during the initial stages of pouring. Higher concentrations of benzene (71432), toluene (108883), ethyl-benzene (100414), and styrene (100425) were measured during pouring and shake out during the EPC than during the green sand process. Screening analyses for 17 polycyclic aromatic hydrocarbons (PAHs) indicated that 13 were emitted during the EPC process using iron versus only two during the green sand process. During aluminum processing, nine PAHs were detected in the EPC process versus only three in the green sand process. Except for naphthalene (91203) and fluorene (86737), which were not detected when aluminum was used in the EPC process, PAH concentrations during the EPC were higher than during the green sand process. The authors conclude that benzene release and heavy soot generation are significant potential hazards associated with the EPC process.