Fine and Ultrafine Emission Dynamics from a Ferrous Foundry Cupola Furnace

Abstract

Aerosol size distributions from ferrous foundry cupola furnaces vary depending on semicontinuous process dynamics, time along the tap-to-tap cycle, dilution ratio, and the physical and chemical nature of the charge and fuel. All of these factors result in a highly time-dependent emission of particulate matter (PM) 2.5 m or less in aerodynamic diameter (PM 2.5 )-even on a mass concentration basis. Control measures are frequently taken on the basis of low-reliability parameters such as emission factors and loosely established mass ratios of PM 2.5 to PM 10 m or less in aerodynamic diameter (PM 10 ). The new environmental requirements could entail unexpected and undesired drawbacks and uncertainties in the meaning and effectiveness of process improvement measures. The development of process-integrated and flue-gas cleaning measures for reduction of particle emissions requires a better knowledge of generation mechanisms during melting. Available aerosol analyzers expand the range of control issues to be tackled and contribute to greatly reduce the uncertainty of engineering decisions on trace pollutant control. This approach combines real-time size distribution monitoring and cascade impactors as preseparators for chemical or morphological analysis. The results allow for establishing a design rationale and performance requirement for control devices. A number size distribution below 10 m in aerodynamic equivalent diameter was chosen as the main indicator of charge influence and filter performance. Size distribution is trimodal, with a coarse mode more than 12 m that contributes up to 30% of the total mass. A temporal series for these data leads to identification of the most relevant size ranges for a specific furnace (e.g., the most penetrating size range). In this cupola, this size range is between 0.32 and 0.77 m of aerodynamic equivalent diameter and defines the pollution control strategy for metals concentrating within this size range. Scrap quality effect is best monitored at less than 0.2 m in aerodynamic equivalent diameter and has been confirmed as strongly dependent on the physical state of the charge.

Correlation between airborne manganese concentration at the workstations in the iron foundry and manganese concentration in workers’ blood

“…where: n 1 -air samples (air-Mn), n 2 -blood samples (B-Mn), Z 1-α/2 -error I (α = 0.05), Z 1-β -error II (β = 0.29), σ 1 2 -variance in group I (study) (0.2), σ 2 2 -variance in group II (control) (0.17), μ 1 -mean in group I (study) (0.38), μ 2 -mean in group II (control) (0.54).…”

“…Ferrous foundry workers are exposed to various manganese (Mn) airborne particles and fumes in the workplaces from both naturally occurring processes and processing activities; because of their small size, fine particles tend to remain and suspending in the air for long periods of time (weeks or months) [1]. Occupational risk assessment is important in foundries and has mainly been based upon airborne manganese measurements.…”

Ultrafine Particle Distribution and Chemical Composition Assessment during Military Operative Trainings

“…Such studies were performed with several UFP detection techniques, for example using a condensation particle counter (CPC), fast mobility particle sizer (FMPS) and aerodynamic particle sizer spectrometer (APS). However, to the best of our knowledge, only a few studies [23] used an electric low-pressure impactor (ELPI), which is considered especially useful for characterizing UFP emissions in occupational settings due to its ability to make real time measurements of particle size distribution and to collect particle for morphological and chemical analysis [13,24,25,26]. …”

Control of pollution emitted by foundries

“…Under this method, these authors have developed a sampling apparatus consisting of sample nozzles, probe and heating compartments. Melendez et al (2010) have reported a research in which the pollutants emitted by foundry cupola furnace were measured using the concentration of particulate matter. These authors have used mg/Nm 3 to indicate the emission of a particulate matter.…”