In this study, the removal performance of high-concentration H2S and complex odors was evaluated for bio-filters installed in sewage treatment plants and manure treatment plants. The amount of odor generation according to temperature was found to be higher in summer than in spring. It was found that the longer the empty bed retention time of the bio-filter, the higher the odor removal efficiency. Therefore, in order to effectively remove odors, it is necessary to maintain a sufficiently long residence time when designing a bio-filter. In addition, a case in which a bio-filter and a wet pre-treatment system were combined to remove high-concentration odors was studied. The result showed that the wet pre-treatment was effective in removing high-concentration odors. In particular, most of the hydrogen sulfide could be adequately removed by wet pre-treatment.

Recently, the air quality issue came to the fore to the occupants of indoor areas with the detection of a large amount of indoor air pollutants such as formaldehyde that causes headache and atopic dermatitis. In order to address this issue, the use of indoor air purifying plants is considered positively as an ecological improvement option. However, the objective performance verification on indoor air-conditioning air volume has not been sufficient. This study aims to verify possible linkage with a building’s air conditioning equipment in order to optimize indoor air-conditioning effects by vegetation bio-filters. To this end, 4 different types of air filter material and AHU (Air Handling Unit) system were linked under air conditions of total wind volume of 400, 600, 800, 1,000 CMH and pressure loss by material was monitored objectively. Finally, material-specific power consumption for system operation was calculated to review energy efficiency. As for pressure loss by material, in terms of total wind volume of 800±1.8 CMH, Pre filter was lowest at –11.69 mmAq and LMF-based vegetation mat was highest at –219.94 mmAq. Based on this, as for material-specific power consumption, the Pre filter, which has the lowest pressure loss, was expected to have power consumption 94.7% lower than the LMF-based vegetation mat.

People today spend 80% of their time indoors and have been showing keen interests in air quality since 2015 due to harmful chemical issues such as humidifier disinfectants. Although plant-based air purification method is widely known to the public, its objective performance and air-conditioning efficiency have been limited. In particular, in the case of publicly used places frequented by many and unspecified persons, high air-conditioning wind volume is required and it is difficult to secure the required total wind volume with the current air purification method using plants. Therefore, in order to secure air-conditioning wind volume when linked with plants, this study aims to verify stability in using vegetation units that can be linked with building air-conditioning equipment. To this end, vegetation units and AHU were linked for 40 hours under no irrigation conditions and ecological environmental changes were monitored objectively. Pressure loss by total wind volume of vegetation units was verified, and soil moisture, Chlorophyll, and FVC were monitored. First, soil moisture was converged to 0% at a spot where wind volume is concentrated in vegetation units. In both of two types of tree species, chlorophyll showed a change of 1.2 - 2.9 SPAD and FVC showed a change of 4-29% after the experiment.

Soil biofiltration is an environmentally-sound technology for elimination of VOCs, odorous and NOx compounds from a low concentration, high volume waste gas streams because of its simplicity and cost- effectiveness. This study investigated the optimal mixture fraction of briquet ash, compost, soil and loess for NOx degradation. Extreme vertices design was used to examine the role of four components on NOx degradation. Under our experimental conditions, 74.5% of NOx degradation was observed, using a model mixture(25% briquet ash, 10% compost, 30% soil and 40% loess) containing 100 ppb of NO. It was shown that experimental design analysis could allow selecting optimal conditions in such biodegradation processes in this study.

Soil biofiltration is an environmentally-sound technology for elimination of VOCs, odorous and NOx compounds from a low concentration, high volume waste gas streams because of its simplicity and cost-effectiveness. This study was performed to evaluate effect of removal of gaseous NOx using a soil and a yellow soil. Over 60% and 48% of NOx from a soil and a yellow soil was removed at the inlet NO concentrations of 423~ 451ppb, respectively. The bio-filter using a soil media was capable of purifying NOx with a different natural processes. Although some of the processes are quite complex, they can broadly be summarized as adsorption into soil pore water, and biochemical transformations by soil bacteria. When the filteration bio-reactor was applied to a soil and a yellow soil, effective NOx removal was obtained for several times and months. These results show that a soil biofilter can be of use as an alternative advanced NOx treatment system.