Odorous compounds were monitored and dispersion modeling was conducted using AERMOD model. for Songtan Industrial Complex (SIC) located in Mogok-dong, Pyeongtaek city. The complex odor at the target area showed an average dilution ratio of 4.5 and low ammonia concentrations were observed (78.3 ppb). Sulfide, methyl iso-buthyl ketone, methyl ethyl ketone and styrene were not detected. The toluene concentration showed as 1233.3 ppb, which was the highest in the target compounds. The diffusion effect of odorous pollutants by wind was confirmed by descending order of concentration, inner-SIC (282 ppb) > downwind site (182 ppb) > upwind site (11.6 ppb). The results of the modeling demonstrated that the complex odors on the west and, south, north and east of the boundaries were dilution ratios of 10 24 and 20, respectively indicating the north and the east of SIC were more vulnerable to odor pollution than other regions.
In Shiwha/Banwal industrial complex, activated carbons are widely used to remove VOCs. General method of regenerating activated carbons is proceeded at high temperature (800℃). But it causes loss of activated carbons and high cost. In this study, activated carbons were treated at a low temperature of 170℃ to avoid these. Desorption reactions were analyzed based on the data obtained from a thermogravimetric analyzer. THC(Total Hydro Carbon) analyzer was used to analyze desorption reaction of activated carbons.
In this study, SAP (Sliding Arc Plasma) was applied to remove ammonia, an odor causing substance under various conditions. From the study, it was found that the SAP angle is related with the plasma radius. As the angle became narrower, the radius became shorter while the plasma became stronger. Results within 30° angle of the electrode and the electrode length of 10 cm or more and the electrode spacing shows high efficiency at 2mm. In short, it was empirically proved that the ammonia removal efficiency increased at the limited plasma range.
Low temperature desorption of the used activated carbons that contain VOCs (Volatile Organic Compounds) produced from Shiwha/Banwal industrial complex were investigated. Iodine number and BET specific surface area of the activated carbons manufactured by N company in China were measured to see their characteristics prior to use in the experiment. Activated carbons were used to adsorb VOCs in a company of Shiwha/Banwal complex. Used activated carbons were collected and desorbed by the desorbing facility. After 1st adsorption and 1st desorption samples were taken for analysis. Desorbed activated carbons were reused in the same company. After 2nd adsorption and 2nd desorption samples were taken again for analysis. 4 samples were analyzed by TGA (Thermogravimetric Analyzer) at 170℃ with a heating rate of 10℃/min. Also, activation energies and reaction orders of desorption reaction were assessed by employing Friedman method and Freeman-Carroll method. The activation energies were 16.86kJ/mol by Friedman method and reaction orders were 0.36∼5.16 by Freeman-Carroll method.
To improve modeling performance of CALPUFF in predicting dispersions of methane as the greenhouse gas and hydrogen sulfide as odor inducing pollutants emitted from Daejeon Landfill, we conducted tracer experiments of C2H2 and compared calculated concentrations by CALPUFF model under different dispersion coefficients with those measured as the tracer. The PG (Pasquill-Gillford) and micro- meteorological options in determining the dispersion coefficients in CALPUFF were tested against the tracer measurements. The results show that the micro-meteorological option, in which the dispersion coefficients are calculated by a similarity theory in planetary boundary layer, leads to a better agreement with the measured tracer concentrations than ISC-PG option.
The relation between civil appeals of odor in major regions of Incheon area and the operation of odor management area was examined for recent several years. From the studies the civil appeals of odors in the odor management area were closely related and estimated to decrease gradually with the tendency of civil appeals of odors neighboring and outside the odor controlled regions showed the tendency of increase in the Incheon area. To explain those phenomena detailed analysis was conducted with quality analysis of those area.