Estimation of PM10-bound manganese concentration near a ferromanganese alloy plant by atmospheric dispersion modelling

Abstract

Numerous studies have associated air manganese (Mn) exposure with negative health effects, primarily neurotoxic disorders. This work presents a description of the emission and dispersion of PM-bound Mn from industrial sources in the Santander bay area, Northern Spain. A detailed day-specific emission estimation was made and assessed for the main Mn source, a manganese alloy production plant under 8 different scenarios. Dispersion analysis of PM-bound Mn was performed using the CALPUFF model. The model was validated from an observation dataset including 101 daily samples from four sites located in the vicinities of the manganese alloy plant. Model results were in reasonable agreement with observations (r = 0.37; NMSE = 2.08; Fractional Bias = 0.44 and Modelled/Observed ratio = 1.57). Simulated and observed Mn concentrations in the study area were much higher than the guidelines proposed by the World Health Organization (WHO) and the U.S. Environmental Protection Agency (USEPA), highlighting the need to reduce the Mn concentrations in the area. Based on the analysis of the Mn source contribution from the ferromanganese alloy plant, some preventive and corrective measures are discussed at the end of the paper. This work shows that CALPUFF dispersion model can be used to predict PM-bound Mn concentrations with reasonable accuracy in the vicinities of industrial facilities allowing the exposure assessment of the nearby population, which can be used in future epidemiological studies.

Use of CALPUFF to predict airborne Mn levels at schools in an urban area impacted by a nearby manganese alloy plant

“…However, an important contribution of the Mn fugitive emissions from these facilities is associated with fine particles generated in the smelter buildings that are not fully captured (Hernández-Pellón et al, 2017). A further strength of the model is that it was able to describe a wide air Mn concentration range in accordance with observations (Otero-Pregigueiro et al, 2018). This allows to simulate a wide range of air Mn monthly levels (1.9-4,401 ng/m 3 and 8.1-2,919 ng/m 3 for cold and warm periods, respectively), estimating the Mn levels at schools located between 500 and 10,950 m from the main source.…”

“…Taking into account 1 that the later one contributed to more than % of Mn emissions in the studied area, 2 different emission scenarios for the ferroalloy plant were considered: the reference 3 scenario based on the emissions that best represented the observations dataset that 4 were assessed in Otero-Pregigueiro et al 2018and additional scenarios based on the 5 implementation of potential preventive and corrective measures (see Table 1). The 6 reference emission scenario (S0) considered a hooding efficiency inside the smelters of 7 96 %, a 50 % of piles surface area not covered and no particulate matter control in the 8 off-gas by-pass pipeline (Otero-Pregigueiro et al, 2018). The additional scenarios focus 9 on the sections where Mn emissions can be strongly reduced: i) Improving the hooding 10 efficiency in furnace buildings, from 96% to 98%.…”

“…This school is located some 500 m from the plant. In a previous campaign, a monthly Mn average concentration of 713.9 ng/m 3 and a maximum daily concentration of 3,204 ng/m 3 were measured in IPJH in August (Hernández-Pellón and Fernández-Olmo, 2016); this site was not used to assess the CALPUFF model developed in our previous work (Otero-Pregigueiro et al, 2018), because the only available site to place the sampler did not fulfill all the requirements for microscale siting (the flow around the inlet sampling probe was partially restricted by one of the buildings of this school). So, the measured Mn concentrations at IPJH were probably underestimated.…”

“…The metal industry database quality is 29 uncertain since most of the emission inventories are not representative of site conditions and operations (Hagelstein, 2009). In a recent study, a day-by-day Mn emission inventory depending on the operating conditions of a ferromanganese plant 1 was developed to run the CALPUFF model to estimate the Mn levels in Santander bay 2 (Otero-Pregigueiro et al, 2018). This model showed a reasonable agreement between 3 observations and Mn modelled values in four sites close to the ferroalloy plant.…”

Air quality assessment and modelling of pollutants emission from a major cement plant complex in Nigeria

“…Dispersion modelling tools that have proven useful in estimating air quality impact of industrial activities on receptor environments include CALPUFF, AERMOD and HYSPLIT (Abdul-Wahab et al, 2018;Abdul-Wahab, 2006;Çetin Doğruparmak et al, 2018;Ma et al, 2018). The AERMOD has been described as a more refined dispersion model in complex and simple terrain for determining the impact of air pollutants emanating from industrial sources on receptors (Abril et al, 2016;Adesanmi et al, 2016;Kumar et al, 2018;Otero-Pregigueiro et al, 2018;Tamjidi et al, 2018;Teggi et al, 2018;Tunlathorntham and Thepanondh, 2017;Tuygun et al, 2017). Determination of concentration levels of pollutants within the fenceline of the plant and those transported to the nearby communities is important.…”