In the dismantling of nuclear power plants, various forms of radioactive gaseous waste are generated when cutting concrete and metal structures. Large amounts of radioactive dust and aerosols generated during the cutting process of each structure can cause radiation exposure to the environment around the workplace and to the radiation exposure in the body of workers. When cutting structures, water is sprayed to reduce the generation of aerosols, so early saturation of the filter is expected due to radioactive aerosols and fine particles containing a large amount of moisture. A mobile air purification device is being developed to a fast and efficient air purifier that can be used for a long time operation to protect workers from radiation exposure in high radiation areas and to minimize the amount of secondary waste generated. In this paper, the direction for a new concept of unit technology that can achieve the development purpose is described.

The emission of particulate matter and volatile organic compounds (VOCs) from a motor vehicle painting booth was quantitatively evaluated. Most particulate matter was emitted during the spraying process, in which the PM10 concentration was 16.5 times higher than that of the drying process. When the paint was being sprayed, the particles with a diameter of 1.0~2.5 μm accounted for 39.4% and particles greater than 2.5 μm in diameter accounted for 30.6% of total particles. On the other hand, small particles less than 0.5 μm in diameter accounted for 52.4% of total particles during the drying process. In contrast to the particulate matter, high concentrations of VOCs were emitted during both spraying and drying processes. Butyl acetate, xylene, toluene, and m-ethyltoluene were the most abundant VOCs emitted from the motor vehicle painting booth. Additionally, xylene, butyl acetate, toluene, and 1,2,3-trimethylbenzene were the dominant ozone precursors. Especially, xylene exhibited the highest ozone production contribution (32.5~44.4%) among 34 species of the ozone precursors. The information obtained in this study can be used to establish a suitable management strategy for air pollutants from motor vehicle painting booths.

Two sewage treatment facilities were selected to identify odor emission characteristics, focusing on volatile organic compounds (VOCs) and sulfur compounds. The complex odor, 5 kinds of sulfur compounds and 23 kinds of VOCs were analyzed from gas and sludge storages. Hydrogen sulfide was detected in the highest concentration and had the highest odor quotient among the odorous compounds monitored in this study, demonstrating that the contribution of hydrogen sulfide to the complex odor reached up to 90%. For VOCs, the overall contribution to the complex odor was not critical but VOCs can sufficiently trigger an odorous sensation because the sum of the odor quotient reached up to 2.89.

This study aimed to estimate the odor emission rate from swine nursery facilities (naturally and mechanically ventilated) using probability distribution. Odor occurrence trends in the study facilities were very different; odor concentration and gas flow had a lognormal distribution. Monte Carlo simulation was used to carry out the uncertainty analysis. Odor emission rate was found to range from 18.05 OU/sec (10th percentile) to 621.88 OU/ sec (90th percentile), and odor emission rate per head ranged from 0.02 OU/sec · head (10th percentile) to 0.64 OU/ sec · head (90th percentile).

The purpose of the present study is to examine characteristics of hydrogen sulfide adsorption using iron-activated carbon composite adsorbents prepared by ferric nitrate and ferric chloride. Prepared adsorbents were discussed on H2S adsorption capacity. Also, adsorbents were analyzed by surface analysis methods for illustrating the physical characteristics of H2S adsorption. The breakthrough tests of H2S were conducted at 3,333 ppm of inlet concentration, demonstrating that the adsorption capacity for iron-activated carbon composite adsorbents was in order of FC_AC (Ferric chloride_Activated carbon), FN_AC (Ferric nitrate_Activated carbon), FC (Ferric chloride) and FN (Ferric nitrate). Adsorption capacity of FC was 0.06 g/g, whereas FC_AC showed the highest capacity of 0.171 g/g. All adsorbents exhibited the amorphous type in physical appearance based on XRD analysis and high Fe content based on EDS analysis. The surface areas of composites were increased by adding activated carbon, exhibiting better adsorption capacity.

This study assessed the analysis method for measuring volatile organic silicon compounds (namely as siloxanes) by usinggas chromatography with flame ionization detector. Calibration standard gas was made in a laboratory by using six volatileorganic silicons as model gas. Two different types of working gas were prepared to evaluate quality control in GC-FIDanalysis. Less than 0.2 RSD% of repeatability of retention time was observed in the analysis of calibration standard gas. Inthe linearity test, the highest coefficient of determination (R2) was found to be 0.997 for L2 among volatile organic siliconcompounds. This study demonstrated that quantification of volatile organic silicon compounds can be performed by usingGC-FID analysis with direct injection mode, and the GC calibration can be covered by the gas-phase standard method.