Odorous emissions from large industrial complexes exhibit significant spatial and temporal variability, which complicates quantitative evaluation and source identification. Odor perception may occur even at low concentrations, and emission characteristics are strongly influenced by industrial processes, meteorological conditions, and local topography. Therefore, odor management strategies based solely on compliance with emission standards have inherent limitations. The Yeosu National Industrial Complex was designated as an odor management area in 2019, and annual surveys of complex odor dilution ratios and specified odor substances have been conducted since then. Despite the accumulation of monitoring data, odor complaints from nearby residential areas have continued. In this study, multi-year (2020-2024) odor monitoring data were integrated with complaint records, and GIS-based mapping and visualization were applied to examine the spatial distribution characteristics of measured odor levels and complaint locations. Map-based visualization facilitated visual comparison of complaint locations and monitoring sites and enabled a comparative assessment between monitoring sites and complaint locations. The results revealed clear spatial heterogeneity among monitoring sites. In particular, the A3 monitoring site recorded the highest annual average dilution ratio, indicating persistent structural characteristics of odor emissions in that area. Although measured odor intensity was relatively higher in summer, complaint frequency peaked in spring and autumn, suggesting that meteorological conditions and human exposure patterns significantly influence perceived odor nuisance. These findings demonstrate that measured odor intensity alone does not fully explain complaint occurrence and highlight the necessity of integrated odor management approaches that incorporate spatial dispersion characteristics, seasonal variability, and community exposure factors. The results can serve as a foundational basis for improving monitoring site placement and establishing spatially differentiated odor management policies.

This study investigated the correlation between compound malodor and total hydrocarbons (THC) to evaluate the potential use of THC as a predictor of compound malodor. A total of 87 samples were analyzed from five target facilities: two petrochemical manufacturing facilities (A, B), a wastewater treatment facility (C), a recycled plastic injection molding facility (D), and a surfactant manufacturing facility (E). The correlation coefficients of compound malodor and THC for each facility were as follows: A: 0.6698, B: 0.8068, C: –0.2767, D: 0.2071, and E: 0.7695. The correlation coefficient for all facilities was 0.5634, indicating a weak correlation. The coefficients of determination for the regression analysis to predict the compound malodor for facilities A, B, and E were 0.4093, 0.6316, and 0.5695, respectively, which validated the results of the correlation analysis. These values improved to 0.8394, 0.6941, and 0.7476 in the multiple regression analysis with the VOC analysis results added as independent variables. Therefore, it is expected that THC measurement that considers the characteristics of the facility can be used to establish a systematic odor management plan.

Yeosu National Industrial Complex is one of Korea’s representative petrochemical industrial complexes where crude oil refining and petrochemical companies are concentrated. According to the results of the 2021 chemical emissions survey, during the process of manufacturing, storage, and transportation at the Yeosu National Industrial Complex, various hazardous chemicals, including hazardous air pollutants, volatile organic compounds and odorous substances are being emitted into the air, affecting the surrounding environment and the health of residents. The Ministry of Environment is applying strengthened standards by designating the Yeosu National Industrial Complex as an air conservation special measure area and establishing odor management areas to manage the air environment. Nevertheless, odor complaints continue to be registered and related complaints increase when turnaround work is carried out. Since air emissions are not counted during periods of turnaround as normal operations are temporarily suspended, it was difficult to establish policies to reduce odor complaints because the source of emissions and emission quantities cannot be ascertained with certainty. In this study, the extensive Yeosu National Industrial Complex was subdivided into 4 areas using a mobile vehicle equipped with PTR-ToF-MS capable of real-time analysis without sample pretreatment being carried out. Measurements were repeated during the day, night, and dawn while moving around the internal boundary of the plant and the boundary of each region where turnaround activities were being carried out. As a result, the recorded measurement for acrylonitrile was the highest at 6340.0 ppb and propyne and propene were measured the most frequently at 128 times each. Based on these results, it will be possible to help reduce emissions through process improvement by efficiently operating air measurement networks and odor surveys that conduct regular measurements throughout the year and providing actual measurement data to the plant. Also, it will help reduce odor complaints and establish systematic air management policies.