In this study, we evaluated the composition of smoke released from fish frying processes. We selected 4 fish types (mackerel (M), hairtail (H), croaker (C), and japanese mackerel (J)) which are commonly served in our daily diet and collected their smoke samples. The analysis was made to cover both toxic and hazardous volatile organic compounds (VOCs) that include benzene, toluene, p-xylene, methyl ethyl ketone, methyl isobutyl ketone, butyl acetate, and isobutyl alcohol. According to our analysis, the mean concentrations (ppb) of VOCs derived from all 4 fish types were 254.5 (benzene), 34.5 (toluene), 833.0 (MEK), 29.4 (MIBK). Benzene as the class one carcinogen was detected at fairly high levels from these fish smoke samples so as to exceed indoor emission standard. Considering that roasted fish is often included as one of the common diet items, we can confirm that the smoke released from cooking should be controlled to reduce the possibility of their exposure to human.
The present study investigated the emission characteristics of odorous elements from a local livestock waste treatment plant. Target materials were sampled twice from each place including the boundaries of the plant, exhaust of a fan from utility-pipe conduit and bio-filter bio-filter chamber. Among the sulfur compounds, methyl mercaptan was 3.0 ppb at the boundaryⅠ, 2.2 ppb at the fan exhaust, and 4,723.3 ppb at the outlet of bio-filter scrubber. In particular, one of main odor control facilities; bio-filter scrubber has released a large volume of methyl mercaptan. It also removes 76.8% of ammonia and 26.5% of trimethylamine.
In order to improve an accuracy of the real-time odor dispersion modeling system, a sensitivity of CALMET model with different input meteorological data was studied. The performance of CALMET model was tested by comparing the model predictions with the observations at the Daedeok Industrial Complex in Daejeon Metropolitan City. It is shown that the CALMET model with WRF (Weather Research and Forecasting) input data of GFS (Global Forecast System) depicts the measurements better than that of RDAPS (Regional Data Assimilation and Prediction System). The CALMET model could be further improved by selecting options of Divergence minimization, Froude number adjustment and Slope flows without choosing Kinematic Effects in the modeling procedure.
The methods of reducing odor by increasing the flow rate with the Gulpo river which has been played a major water course in Incheon area were investigated with the measurement of odor concentration using air dilution sensory methods in the flow river. The odor concentrations were diminished with the rise of the flow rate and the optimal condition of maintaining the flow rate were determined from those results.
This study was carried out to suggest a realtime evaluation system for the odor adsorption efficiency with electrochemical sensors. As the results of the experiments for the realtime evaluation system, the correlation coefficient between the sensor signals and the hydrogen sulfide concentration was relatively good, 0.9920 and 0.8340, respectively. The relative standard deviation of three replicative experiments for the adsorption amount in the conditions of 0.5 g and 1.0 g of adsorbent was 6.97% and 3.49%, respectively. This study would contribute the realtime evaluation of odor control efficiency to overcome the limitations of olfactory method and instrumental analysis in terms of cost and technology.
In this study, the catalytic combustion of propionaldehyde, which is an Offensive Odorant Substance assigned by the Korean Ministry of Environment (KMOE), over alumina-supported manganese oxide (Mn/Al2 O3) catalysts was investigated. The combustion reaction was carried out in a fixed-bed reactor at the temperature range of 200 ∼340 ℃. Mn/Al2O3 catalysts with Mn loadings ranging from 3.9 to 18.3 wt.% were prepared by impregnation method. The physicochemical characteristics of the catalysts were analyzed by X-Ray Diffraction (XRD), Scanning Electronic Microscopy (SEM) and Brunauer-Emmett-Teller (BET). The Mn crystalline phases of the Mn/Al2O3 catalysts were identified as α-Mn2O3 and β-MnO2. Mn oxides were covered on γ-Al2O3 supports with an average diameter of around 1 μm. With the increase of Mn loadings, the BET surface areas, pore volumes and average pore diameters of the Mn/Al2O3 catalysts decreased. The catalytic activities of Mn/Al2O3 catalysts increased as the Mn loading was increased from 3.9 wt.% to 18.3 wt.%. The catalyst with 18.3 wt.% Mn loading was able to achieve 100% propionaldehyde conversion at 260 ℃. For the same temperature, a lower Gas Hourly Space Velocity (GHSV) and a lower propionaldehyde concentration promote the complete combustion of propionaldehyde.