• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.91-97
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• 2002

Removal of malodorous gases from swine manure by a polyurethane biofilter inoculated with heterotrophic and autotrophic bacteria was investigated. Ammonia, hydrogen sulfide and other gases could be efficiently treated at 3~3.6 second of empty bed retention time by the polyurethane biofilter. In the range of SV $200~l,200h^{-1}$ , the average removal efficiency of odor was about 89% when the odor unit of inlet gas was below 4100. Odor elimination capacity of the polyurethane biofilter was$ 1.8$\times$10^{5}$ $~5.0$\times$10^{7}$OUㆍm$^{-3}$ㆍ$h^{-1}$ that were 84~90% of the inlet load. The critical loads of $NH_3$ and $H_2$S, which mean 97% removal with respect to the inlet loads, were 31 and $27 g.m^{-3}$ ㆍ$h^{-1}$ , respectively. The maximum elimination capacities of $NH_3$ and $H_2$S were 56 and $157 gㆍm^{-3}$ ㆍh$^{-1}$ , respectively. Although the removability for$ NH_3$ and $H_2$S was not influenced by $H_2$S$NH_3$ ratio (ppmv/ppmv), the $H_2$S removability was inhibited by high $H_2$S concentration more than 80 ppmv.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.70-76
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• 2003

The benzene removal characteritics of the polyurethane (PU) biofilter immobilized with S. maltophilia T3-c, that could efficiently degrade benzene, was investigated. Maximum capacity to eliminate benzene was maintained at $100-110g{\cdot}m^-3{\cdot}h^-1$ when space velocity (SV) ranged from 100 to $300 h^-1$ -1/, however, it decreased sharply to $55 g{\cdot}m^-3{\cdot}h^-1^$ as SV increased to $400 h^-1$. The critical elimination capacities that guaranteed $90\%$ removal of inlet loading of the PU biofilter were determined to be 70,30, and $15 g{\cdot}m^-3{\cdot}h^-1$ at SV 100,200, and $300 h^-1$, respectively. Based on the result of a kinetic analysis of the PU biofilter, maximum benzene elimination velocity ($V_m$) was $125 g{\cdot}m^-3^\;of\;PU{\cdot}h^-1$ and saturation constant ($K_m$) was $0.22 g{\cdot}m^-3^$ of benzene ($65{\mu}{\cdot}I^-1$). This study suggests that the biofilter utilizing S. maltophilia T3-c and polyurethane is a very promising technology for effectively degrading benzene.

• Journal of Animal Environmental Science
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• v.8 no.1
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• pp.1-8
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• 2002

Real sized open type biofilter system was manufactured to control the odor generated from the agitated composting system which composted swine manure and sawdust mixtures. The aim of this research was to develop a biofilter system using matured compost and to evaluate the performance of the biofilter system. Average ammonia reduction rate through the biofilter was 84% during about two month period of composting. The maximum ammonia concentration after filtering was 45ppm lower than allowable value of 50ppm. It was concluded that compost can be used as a biofilter materials.

• Analytical Science and Technology
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• v.31 no.2
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• pp.57-64
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• 2018

The biodegradation of toluene vapor was investigated using a new type of biofilter equipped with a laboratory-scale evaporative cooler model packed with wood wool fibers (area: $360cm^2$). For the purpose of this study, the biofilter system was inoculated with Pseudomonas sp. RSST (MG 279053). The performance of this biofilter, assessed in terms of toluene removal efficiency (and elimination capacity), was as high as 99 % at a loading rate of $6g/h{\cdot}m^2$. The toluene removal efficiency decreased in an exponential manner with the increase in the loading rate. The cooler model-based biofilter was able to remove more than 99 % of toluene using Pseudomonas sp. RSST (MG 279053) as an effective inoculum. This biofilter is designed to operate under batch conditions for the removal of toluene in confined environments (e.g., automotive plants, boiler rooms in manufacturing facilities, and offshore drilling platforms).

• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.678-686
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• 2006

The feasibility of the high-hydrophilic biofilter was examined for application in rural wastewater treatment in Korea. The intermittent trickling biofiter was developed for wastewater treatment of media and examined instantaneous wetting water and immersional wetting water. Melamin foam absorbed 120 times it's weight in water and maintained wetting status than other materials. These characteristics are improvement for application in rural areas showing large variance of amount of influent. The biofilter process was effective in treating organic pollutants; mean removal efficiencies of $BOD_5$ and TSS were above 80%. The average SS concentrations of effluent was showed below $10mg/L^{-1}$ and meet guidelines in special regions, however, the average concentration of $BOD_5$ was about $20mg/L^{-1}$. The removals of T-N and T-P were relatively less effective and removal efficiencies were below 40%. It might meet the guidelines for T-P because of low levels of influent T-P concentration. However, the T-N concentration were too high and further treatment is required. The effluent concentration of $NH_4-N$ showed a significant reduction rate about 43.8%, but part of $NH_4-N$ was transformed to $NO_2-N$ and $NO_3-N$ inside the biofilter through nitrification process. The effluent concentration of org-P was removed about 78.8% of influent concentration by filtration. Considering stable performance and effective removal of pollutant in wastewater, low maintenance, and cost-effectiveness, the hydrophilic biofilter system was thought to be an effective and feasible alternative for decentralized rural areas.

• Journal of Environmental Impact Assessment
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• v.9 no.1
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• pp.39-46
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• 2000

Removal of ammonia using the porous ceramic biofilter inoculated with earthworm casts was characterized. By assuming a plug air flow in the biofilter and applying the Michaelis-Menten equation, the maximum removal rate of $NH_3$ was $280.7g-N{\cdot}m^{-3}{\cdot}h^{-1}$($18.0g-N{\cdot}kg^{-1}{\cdot}d^{-1}$) at $30^{\circ}C$. $NH_3$ removal rate was increased as temperature increases from $15^{\circ}C$ to $35^{\circ}C$. The maximum removal rate was $285.8g-N{\cdot}m^{-3}{\cdot}h^{-1}$($18.8g-N{\cdot}kg^{-1}{\cdot}d^{-1}$) at $35^{\circ}C$. At $15^{\circ}C$, the $NH_3$ removal rate was $122.8g-N{\cdot}m^{-3}{\cdot}h^{-1}$($8.1g-N{\cdot}kg^{-1}{\cdot}d^{-1}$). When 210 ppm $NH_3$ was supplied to the biofilter at space velocity of $220h^{-1}$, the removal efficiency of $NH_3$ at 15, 25, 30 and $35^{\circ}C$ was 80, 90, 95, and 96%, respectively. The removal rate of the ceramic biofilter was 3 to 15 times higher than other biofilters comparing the removal efficiency of $NH_3$ per unit volume of carrier. This result indicates that earthworm casts and porous ceramics are very good inoculum source and carrier, respectively, for the $NH_3$-degrading biofilter.

• 보일러설비
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• s.73
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• pp.98-99
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• 2000

• Journal of Soil and Groundwater Environment
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• v.10 no.1
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• pp.35-42
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• 2005

This research was investigated the applicability of the biofiltration technology for the removal of volatile organic carbons (VOCs) produced from the bioremediation of oil contaminated soil. Diesel was used as surrogate for oil and, two types of biofilter systems made of ceramic and polymer media were compared for the removal efficiencies of diesel VOCs at different inlet concentrations and space velocity (SV) conditions. During the first 30-d operation, the removal efficiencies of the biofilter packed with polymer and the biofilter packed with ceramic were investigated at constant SV of $153\;h^{-1}$ When inlet concentrations of diesel VOCs were below 10 ppmv, the average removal efficiencies of the polymer biofilter and the ceramic biofilter were average $67\%\;and\;75\%$, respectively. When the inlet concentration increased to 30 ppmv, the VOC removal efficiency in the polymer biofilter was $80\%$, while the average removal efficiency in the ceramic biofilter was $60\%. Effect of the inlet concentration and SV on the removal efficiency of total diesel VOCs was investigated. As SV increased from $153\;h^{-1}$ to $204\;h^{-1}$ and $306\;h^{-1}$, the removal efficiency of total diesel VOCs was decreased gradually. The average removal efficiency of the biofilter packed with polymer carrier was decreased from $82\%\;to\;80\%\;and\;77\%$. The biofilter packed with polymer carrier showed that the removal efficiency of benzene and toluene were maintained within the range of $81\%\~86\%$. In contrast, for the biofilter packed with ceramic carrier, when SV increased from $153\;h^{-1}$ to $204\;h^{-1}$ and $306\;h^{-1}$, the removal efficiency of benzene decreased from $87\%\;to79\%\;and\;74\% . respectively. The removal efficiency of toluene decreased from $80\%\;to\;77\%\;and\;76\%$ at SV of $153\;h^{-1},\;204\;h^{-1}\;and\;306\;h^{-1}$, and $306\;h^{-1}$, respectively.

• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.116-124
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• 2022

In this study, waste air containing ethanol and hydrogen sulfide, was treated by an integrated hybrid system composed of two alternatively-operating UV/photocatalytic reactor-process and biofilter processes of a biofilter system having two units with an improved design (R reactor) and a conventional biofilter (L reactor). Both a pressure drop (△p) per unit process of the integrated hybrid system and a microbe-population-distribution of each biofilter process were observed. The △p of the UV/photocatalytic reactor process turned out very negligible. The △p of the L reactor was observed to increase continuously to 4.0~5.0 mmH₂O (i.e., 5.0~6.25 mmH₂O/m). In case of R reactor, its △p showed the one below ca. 16~20% of the △p of the L reactor. Adopting such microbes-carrying biofilter media with high porosity as waste-tire crumb media, and the improved biofilter design, contributed to △p of this study, reduced by ca. 37~50% and 40~53%, respectively, from the reported △p of conventional biofilter packed with biofilter media of the mixture (50:50) of wood chip and wood bark. In addition, the △p of R reactor in this study, reduced by ca. 80% from the reported △p of conventional biofilter packed with biofilter media of the mixture (75:25) of scoria with high porosity and compost, was mainly attributed to adopting the improved biofilter design. On the other hand, in case of L reactor, the CFU counts in its lowest column was analyzed double as much as those in any other columns. However, in case of R reactor, its CFU counts were bigger by 50% than the one of L reactor and its microbes were evenly distributed at its higher and lower columns of R_dn reactor and R_up reactor. This phenomena was attributed to an even moisture distribution of 50~55% of R reactor at its higher and lower columns. Therefore, R reactor showed superb characteristics in terms of both △p and microbe-population-distribution, compared to L reactor.

• Clean Technology
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• v.18 no.2
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• pp.209-215
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• 2012

The performance and removal efficiencies of a pilot scale biofilter were estimated by using ammonia and hydrogen sulfide as the odorous gases. Expanded polyurethane foam coated with powdered activated carbon and zeolite was used as a biofilm supporting medium in the biofilter. Odorous gases from the sludge thickener of a municipal wastewater treatment plant were treated in the biofilter for 10 months and the inlet ammonia and hydrogen sulfide concentrations were 0.1-1.5 and 2-20 ppmv, respectively. The removal efficiencies reached about 100% at the empty bed retention time (EBRT) of 3.6-5 seconds except for the adaptation periods. The pressure drop of the biofilter caused by the gas flow was also low that the maximum attained was 31 mm $H_2O$ during the operation. Its stability was confirmed in the long term due to the fact that the biofilter and the polyurethane medium had a minimum plugging and compression. The microbial community on the medium is critical for the performance of the biofilter especially the distribution of ammonia oxidizing bacteria (AOB) and sulfur oxidizing bacteria (SOB). The distribution of Nitrosomonas sp. (AOB) and Thiobacillus ferroxidans (SOB) was confirmed by FISH (fluorescence in situ hybridization) analysis. The longer the operation time, the more microbial population observed. Also, the medium close to the gas inlet had more microbial population than the medium at the gas outlet of the biofilter.