This study evaluated the effectiveness of odor reduction when spraying inside the Bio-curtain (hereinafter referred to as curtain) according to the exhaust fan operating rate. Spraying is a main factor affecting the ability to odor reduction of curtains. The curtain (total area: 37.9m3) was constructed with two layers of light-shielding screens stretched over a rectangular parallelepiped structure installed around an exhaust fan (630 mm) on the side wall of a pig barn. Air samples for odor analysis were collected from inside the pig barn and outside the curtain. The main odorous compounds such as volatile fatty acids, phenols, indoles, and ammonia were measured. The odor reduction effectiveness was evaluated by total odor activity values (TOAVs) summed to the odor activity values of each odorous compounds. Depending on the exhaust fan operating rate, the reduced rate of TOAVs gradually decreased to the range between 15.67% and 68.80%. Because the contact time between the spraying liquid and the air velocity of the exhaust fan becomes shorter (or there is a reduction in liquid to gas flow ratio) as the exhaust fan operating rate increases. The results of this study can be used as basic data for research into spraying conditions to improve the odor reduction effectiveness of curtains.

This review paper aimed to comprehensively assess the ventilation methods and ventilation rates of livestock sheds, various livestock odor mitigation technologies, and the design flow rate of odor mitigation devices. The most efficient ventilation method for livestock odor control was found to be mechanical ventilation. When livestock odor is at its most severe during summer, ventilation systems are operated at the maximum ventilation rate, which is 5-25 times higher than the ventilation rate in winter. Therefore, the mitigation facilities of livestock odor must be designed while considering the maximum ventilation rate. There is a significant amount of research data on various livestock odor control technologies using various physical, chemical, biological, and complex technologies applied to livestock farms. Biofiltration and photocatalytic oxidation are considered the most promising methods due to their cost-effectiveness and simplicity. Biofiltration is effective for removing hydrophilic odors, but requires improvement for the efficient removal of hydrophobic odors and the control of accumulated excess biomass. The advantages of the photocatalytic oxidation method include its excellent hydrogen sulfide and ammonia removal rates and relatively low ozone emissions. However, it requires technology to reduce nitrous oxide emissions. Investment in installing and operating these odor mitigation technologies is only realistic for large-sized farms. Therefore, it is imperative for small and medium-sized livestock farms to develop odor mitigation technology that is inexpensive and has low installation, operation, and maintenance costs.

This review comprehensively summarizes the livestock odor reduction method by dietary manipulation, in-housing management, and manure management. The gut microbial metabolism of animals can be stimulated by low-crude protein feeding and the addition of probiotics, enzymes, plant extracts, and/or organic acids to their feed. These methods can result in reduced odor emissions from manure. For in-housing management, it is important to maintain the proper breeding density in the barn facilities, regularly remove dust and manure, and periodically clean the barn facilities. A barn using litter on the floor can reduce odor at a relatively low cost by adding adsorbents such as zeolite, biochar, etc. Although masking agent spraying can be the simplest and quickest way to control odors, it is not a fundamental odor mitigation strategy. Odor emissions can be reduced by installing covers on manure slurry storage facilities or by acidifying the manure slurry. It is necessary to install a solid-liquid separator in an enclosed facility to minimize odor emissions. Other methods for reducing odor emissions include covering manure composting plants with semi-permeable membranes or using reactor composting technology. In order to minimize odor emissions in the liquid manure composting, sufficient oxygen must be supplied during the fermentation process. Furthermore, the odor reduction effect can be achieved through the liquid manure pit recharge system which supplies matured liquid manure fertilizer to the slurry pit in the pig house.

The distance between livestock facilities and residential spaces is decreasing. Moreover, livestock odor complaints are increasing due to the large-scale and concentrated livestock breading industry. In order to reduce odor from livestock facilities, bio-curtain that are easy to install and inexpensive are commonly used in Korea. However, there is a lack of basic data on design standards and operation manuals for bio-curtains. The installation density of the bio-curtain material is an important factor that affects the odor reduction rate, increment of the load on the ventilation fans, and the structural stability of the curtain. There are limitations on deriving the design conditions of the bio-curtain by only field experiments targeting invisible air. Therefore, aerodynamic simulation such as CFD (computational fluid dynamics) can be used to obtain quantitative data according to various environmental conditions. Bio-curtain is a porous medium with a complex structure, and it is necessary to derive aerodynamic coefficients to analyze it. In this study, the wind speed and pressure difference according to the design density of the bio-curtain were monitored using the experimental chamber. Using the field results, a pressure resistance curve was created for each flow velocity and installation density. The viscosity and resistance coefficient of the bio-curtain were calculated through the derived resistance curve.

The present trial verified the effects of spraying microbial agents on odor reduction in commercial pig farms of different operating sizes and barn types. Farms without microbial agent spraying and those sprayed with microbial agents at two different intervals were compared. The treatments included spraying of water alone every day or a mixture of water plus microbial agent at 24 and 72 h intervals. The experimental farms were divided according to size into 1,000-, 3,000-, and 5,000-head farms and according to barn type into gestation, farrowing, nursery, and grower-finisher farms. To compare odor concentration within each housing barn, ammonia and hydrogen sulfide gas levels were measured. The average concentrations of ammonia (p<0.01) and hydrogen sulfide (p<0.05) gas were the lowest in all types of farms sprayed with the microbial agent at a 24 h interval. In farms sprayed with the microbial agent at a 24 h interval, the decrease in ammonia concentration according to barn type was in the following order: farrowing (p<0.01) (11.0 to 1.8 ppm), nursery (p<0.05) (17.0 to 9.2 ppm), grower-finisher (15.3 to 8.8 ppm), and gestation (9.7 to 6.4 ppm) farms. Moreover, spraying the microbial agent at a 24 h interval significantly (p<0.01) decreased ammonia concentration from 19.9 to 10.4 ppm, from 11.1 to 4.1 ppm, and from 8.8 to 5.1 ppm in 5,000-, 3,000-, and 1,000-head farms, respectively. Overall, spraying microbial agents every day may be the most effective method to reduce odor in commercial pig farms.

본 연구의 목적은 악취 발생 저감을 위해 국내에서 최근 권고되는 밀폐(무창)형 돈사와 기존 개방형 돈 사의 비용 편익을 분석하여 이러한 추진 방향의 객관적 타당성을 확보하는 데 있다. 두 돈사 유형의 비용은 설치비와 운용비로 구분한 후 관련 문헌 자료와 현장 조사 결과를 근거로 추정하였고, 편익은 축산 환경 전문가들을 대상으로 한 델파이 설문 조사 기법 적용을 통해 추정하였다. 비용 편익 분석 결과, 양돈 규모에 상관없이 개방형과 밀폐형 돈사 모두 편익/비용 비율이 1 초과로 추정되어 돼지 생산에 따른 경제적 이익이 창출되는 것으로 분석되었다. 하지만 소규모, 중규모, 대규모 양돈 농가 모두 밀폐(무창)형 돈사의 편익/비용 비율(B/C ratio)이 개방형 돈사보다 상대적으로 모두 높은 것으로 추정되었다. 결론적으로 기존 양돈 농가들의 인·허가 시 경제성 우위 측면뿐만 아니라 축산 악취의 효율적 관리를 위해서도 개방형 돈사를 밀폐(무창)형 돈사로 변경하도록 권고해야 하며, 특히 편익/비용 비율이 상대적으로 가장 높은 수치를 보인 대규모 농가인 경우 이를 이행 조치하는 것이 합리적이라 판단된다.

본 연구는 계란 생산성, 계란품질 및 악취저감에 관한 Bacillus subtillus, Streptomyces galilaeus 및 Sphingobacteriaceae로 구성된 복합생균제(PM, probiotic mixture)의 효과를 조사하였다. 산란계 Hy-Line Brown 240수를 4처리구로 구분하여 6주 동안 사육하였다. 처리구는 복합생균제를 함유하지 않은 대조구(CON, control), 일반생균제(CP3, commercial probiotics 0.3%), 복합생균제 3(PM3, 복합생균제 0.3%), 복합생균제 5(PM5, 복합생균제 0.5%)로 구분하였다. 산란율, 계란 호우유니트, 난각두께, 난각강도, 난황색 및 농후난백 높이는 PM3, PM5가 CON 및 CP3에 비해서 높았다. 계분으로부터 암모니아, E. coli, 총호기성균, Coliform, Salmonella 균수는 CON>CP3>PM3>PM5 순서로 증가하였다. 본 결과는 B. subtillus, S. galilaeus 및 Sphingobacteriaceae로 구성된 복합생균제 0.3%가 산란율, 계란품질 개선 및 분에서 암모니아 발생을 낮추어 양계장 악취저감 효과를 갖는다는 점을 보여 준다.

The aim of this study was to evaluate the odor reduction in swine farms by the application of probiotics. A total of five farms were selected from the preliminary survey based on the management scale, odor gas concentration level, and production efficiency. The application of probiotics consisted of feeding swine high concentrations of probiotics, addition of odor-reducing agents in the slurry pit, and the spraying of swine houses. The concentration of probiotics given per pig per day was above 107 cfu/g. The odor was measured before and after probiotics application for 77 days in the swine farms. With the exception of E farm, the odor concentration decreased in four farms with probiotics application. Ammonia and amine concentrations were reduced by 48.24% and 45.37% on average, respectively. The main causes of odor were hydrogen sulfide, p-cresol, and butyric acid. The total odor activity value was the lowest in D farm, followed by B, A, E, and C farms, respectively in increasing order. In the case of C farm, hydrogen sulfide accounted for 92% of the total odor activity value. In order to verify the reliability and effectiveness of probiotics at the farm site, appropriate application and monitoring should be performed continuously on the basis of the product quality evaluation system.

본 연구는 돈사 내 저장된 돼지분뇨 슬러리에 액상 일라이트와 일라이트 분말을 첨가하여 악취에 미치는 영향을 분석하였다. 공시 돼지는 3원교잡종(Yorkshire×Land race×Duroc) 4개월령 암컷 비육돈 (65~68 kg) 360두를 이용하였다. 시험구 배치는 무처리한 대조구와 돼지분뇨 슬러리에 일라이트 액상 33%와 분말 5%를 첨가한 처리구로 3반복(40두) 120두에 적용하여 완전 임의배치법의 3주간 사양 시험 하였다. 악취 저감제 처리는 슬러리 피트(slurry pit ; 3.75 m×9 m×1.2 m, 20 ton 저장 규모)아래에 저장된 슬러리양을 계산하여 일정한 비율에 맞추고, 매주 액상 일라이트는 분무하거나 또는 일라이트 분말은 뿌려주었다. 악취 측정은 슬러리 피트 위 10 cm 위치에서 암모니아, 황화수소, 메틸 메르캅탄 및 디메틸 설파이드를 측정하였다. 사양기간 동안 암모니아 발생량은 일라이트 처리 형태에 의해 크게 영향을 주었다(p<0.05). 특히 암모니아 발생량은 액상 일라이트 33% 처리구는 30~46%, 일라이트 분말 5% 처리구에서는 30~54% 감소되었다. 황화수소 발생량은 2018년 12월 24일에 측정된 결과를 제외 하고 사양기간 동안 일라이트 처리 형태에 따라 유의적으로 영향을 주었다(p<0.05). 처리구의 황화수 소 발생 감소량은 대조구와 비교할 때, 액상 일라이트 33% 처리구에서는 16~60%, 일라이트 분말 5% 처리구는 7~59%였다. 측정기간 동안 평균 메틸 메르캅탄과 디메틸 설파이드 농도는 모든 시험구에서 발생되지 않았다. 3주간 사양 시험에서 평균 암모니아 농도의 경우, 액상 일라이트 33% 처리구는 38.6%, 일라이트 분말 5% 처리구는 39.7% 감소되었다(p<0.05). 평균 황화수소 농도는 액상 일라이트 33% 처리구와 일라이트 분말 5% 처리구는 비슷한 수준인 42.5% 감소되는 것으로 나타났다(p<0.05). 결론적으로 본 사양시험의 결과 액상 또는 분말 일라이트 처리는 돈사 내 발생되는 암모니아와 황화수소에 대한 유의미한 저감효과를 나타내었다.

The odor substances generated in a feed manufactory operating for the commercialization of animal-vegetable materials were analyzed and the odor reduction efficiency by a chemical scrubber was evaluated. The major causative substances in the feed manufactory comprised about 45.4% of ketone compounds and about 13.3% of aldehyde compounds. On the other hand, the removal efficiencies of diacetyl and acetoin as ketone compounds were 77.3% and 78.1%, respectively, by a chemical scrubber. Additionally, the removal efficiencies of acetaldehyde, butyraldehyde, valeraldehyde, 2-furancarboxaldehyde, and nonanal were 86.0%, 78.9%, 67.4%, 52.8%, and 71.9%, respectively. These rates were higher than the odor generation substance contribution rate as a result of treating the exhaust gas generated from the feed manufactory by the chemical scrubber using 5% of C3. It was also found that xylene, methylcyclopentane, benzene, ethylbenzene, 1,3,5-trimethylbenzene, and decane were almost not removed.

Urban sanitary sewer systems can aid in preventing inundation, and can improve civil health by effectively disposing stormwater and wastewater. However, since sewage odor can cause adverse effects, numerous technical and administrative studies have been conducted for reducing such odor. European countries and the United States of America (USA) built modern sewer systems in the late 19th century, and have since been endeavoring to eliminate sewage odors. Several cities of the USA, such as Los Angeles (LA) that has a separate sewer system and San Francisco (SF) that has a combined sewer system, have produced and distributed odor control master plan manuals. Features common in the odor reduction plans of both these cities are that the odor reduction programs are operated in all the respective local regions and are supported by administrative systems. The primary aspectual difference between the two said programs is that the city of LA employs a sewage air purification system, whereas the city of SF controls the emission of major odor causing compounds. Compared to the existing sewer odor reduction systems of these two cities, South Korea is still in the initial phase of development. Through technical studies and policy implementations for sewer odor reduction, a foundation can be laid for improving the civil health quality.

As of 2014, 26.4% of the total regulated odor emission facilities are occupied by livestock facilities. The odor of pigs is 10.9 OU·m3 / min per pig, which generates 15-50 times higher odor than other livestock. It is also a major cause of livestock odor complaint. Livestock odor substance is mixed 169 kinds of ingredients, 30 of which can be detected as odor. It contains sulfur, volatile fatty acids, phenols and indoles, ammonia and volatile amines. In particular, odorous substances of phenols and indole derivatives not included in domestic designated odor substances have high odor contribution and are not well decomposed. Therefore, it is known that despite the use of the odor reducing agent having a high removal rate of ammonia and the like, the residue is long and causes continuous discomfort. The odor problem using physical and chemical methods can not be solved because it can not solve the fundamental problem if the animal odor is not decomposed or removed. In the anaerobic environment, the bacteria present in the manure may produce volatile organic compounds, which are the cause of the odor, and the odor may be generated, and some microorganisms decomposing the odor substances may reduce the odor. B. subtillis, Saccharomyces cerevisiae, L. acidophillus, Enterococcus faecium, L. plantarum, B.coagulans, B. fermentum, B. thuringiensis, B. licheniormis, B. subtillis, Enterococcus faecium, Lactobacillus acidophllus, L. fermentum, L. lactis, L. plantarum, L. casei, L. brevis, Streptococcus faecium, Clostridium butyricum, Saccharomyces cerevisiae, Aspergillus niger, A. oryzae, and photosynthetic bacteria are used as odor-reducing microorganisms.

본 연구의 목표는 분변토로부터 분리한 Bacillus subtilis외 2종의 복합 생균제를 이용하여 제 조한 발효사료가 산란계 생산성, 계란품질 및 양계장 악취저감에 미치는 효과를 조사하는 것이었다. 산 란계 240마리를 4개의 처리구로 구분하여 완전임의 배치하였다. 실험 처리구는 대조구, 분변토발효사료 0.3, 0.5% (FECF3, FECF5), 일반생균제 0.2% (CP)로 구분하였다. 산란율은 일반사료를 섭취한 대조구 와 비교할 때 FECF 처리구는 유의하게 높았으나 CP 처리구는 차이가 없었다. 호우유닛, 난각두께, 파 란강도, 난황색 지수 및 농후난백 높이는 대조구와 비교할 때 FECF 처리구가 증가하였으나 CP 처리구 와 차이는 없었다. 계란의 n-3 함량은 대조구와 비교할 때 FECF 처리구가 높았으나 n-6/n-3 비율은 낮았으며 CP 처리구와의 차이는 없었다. 계분을 실온에서 5일간 방치 후 암모니아 발생량은 대조구와 비교할 때 CP와 FECF 처리구가 낮았다.

The most effective microbial strains with the best ability to reduce complex odor were isolated from earthworm and activated sludge and identified using a 16S rDNA method. The isolated strains, Staphylococcus cohnii HYC-3 and S. carnosus JYC-4, were inoculated into the odor vials that had been left for 48 hours in water containing sesame dregs, and after 3 days, the ammonia was reduced to 5 ppm and 3 ppm from the initial 25 ppm, respectively. Complex odor was reduced to 2.5 and 2.2, respectively, while the control group maintained an odor of 5. The isolates were grown in the order of 30°C > 40°C > 20°C > 10°C. For HYC-3 and JYC-4, the optimum pH was 7 and 10, respectively, and the strains grew well at neutral pH ranges. To monitor the amount of microorganisms remaining in the environment by using the strain as a preparation for odor reduction, a probe for real-time PCR was designed. Through the quantitative and sensitivity tests on the developed strains, it was found that they showed excellent sensitivity.

In order to reduce odor and methane emission from the landfill, open biocovers and a closed biofilter were applied to the landfill site. Three biocovers and the biofilter are suitable for relatively small-sized landfills with facilities that cannot resource methane into recovery due to small volumes of methane emission. Biocover-1 consists only of the soil of the landfill site while biocover-2 is mixed with the earthworm casts and artificial soil (perlite). The biofilter formed a bio-layer by adding mixed food waste compost as packing material of biocover-2. The removal efficiency decreased over time on biocover-1. However, biocover-2 and the biofilter showed stable odor removal efficiency. The rates of methane removal efficiency were in order of biofilter (94.9%)>, biocover-1(42.3%)>, and biocover-2 (37.0%). The methane removal efficiency over time in biocover-1 was gradually decreased. However, drastic efficiency decline was observed in biocover-2 due to the hardening process. As a result of overturning the surface soil where the hardening process was observed, methane removal efficiency increased again. The biofilter showed stable methane removal efficiency without degradation. The estimate methane oxidation rate in biocover- 1 was an average of 10.4%. Biocover-2 showed an efficiency of 46.3% after 25 days of forming biocover. However, due to hardening process efficiency dropped to 4.6%. After overturn of the surface soil, the rate subsequently increased to 17.9%, with an evaluated average of 12.5%.

물리화학적 처리에 의한 양돈장 악취저감 효과를 분석 하기 위하여 물리적 처리 방법인 커튼과 화학적 처리 방법 인 오존수 분무를 병합처리 하는 오존수커튼 시스템을 상 업적인 양돈장에 설치하고 처리 및 설치 전․후의 악취발생 특성과 악취저감 효과를 조사한 결과를 요약하면 다음과 같다. 오존수커튼 시스템은 돈사내부의 악취물질과 먼지를 배기구를 통해 커튼 내부로 포집 후 오존수의 강력한 산화 력으로 악취를 제거하는 안정적인 물리화학적 처리 방법 임을 확인하였다. 오존수커튼 시스템 설치 후 돈사 내부의 암모니아, 황화수소, 트리메틸아민, 휘발성 유기화합물 및 복합악취 농도가 높은 반면, 커튼 외부와 부지경계선에서 는 현저하게 감소되었으며, 악취발생량 또한 크게 감소되 었다(p<0.01). 측정위치별 악취물질농도와 악취발생량은 암모니아, 황화수소, 트리메틸아민, 휘발성 유기화합물 및 복합악취 모두 계절에 관계없이 돈사 내부, 커튼 외부 및 부지경계선 순으로 높았다(p<0.01). 돈사 내부의 악취물질 농도는 환기량이 적은 봄과 겨울에 높고 환기량이 많은 여 름과 가을에 낮았으나, 돈사 외부와 부지경계선에서의 악 취물질농도는 돈사 내부와 상반되는 결과를 나타내었다. 이상의 결과를 요약하면, 양돈장에서 배출되는 악취물질은 오존수커튼 시스템에 의한 물리화학적 처리로 90% 이상 저감 가능한 것으로 판단되며, 양돈장 외부로의 악취물질 확산을 효과적으로 차단함으로써 악취민원 제거를 위한 효율적인 악취저감시설로 활용 가능성은 충분한 것으로 사료된다.

The purpose of this study is to produce the auxiliary fuel additives that will improve the heat value and reduce the odor of dried sewage sludge, an auxiliary fuel for power plants using process by-products. Through an odor analysis prior to the production of auxiliary fuel additives, it was confirmed that the main odor materials are Methylmercaptan, Acetaldehyde and Trimethylamine. Based on this, we measured the heating value on various processes by-products such as by-products of thermal power generation and by-products of refinery. In addition, the adsorption performance in the major odor material was evaluated. However, for Trimethylamine, it is very difficult to secure the reproducibility of the concentration of the standard materials as the standard material is liquid. Therefore, it was used Ammonia, which has basic property, to replace Trimethyamine. In the evaluation of various process by-products, the highest heating value in heavy oil fly ash was 5,575 kcal/kg, while in the adsorption performance evaluation, FCC was shown as having the best performance in adsorption, as it could adsorb 100% of Methylmercaptan, 47% of Acetaldehyde and 76% of Ammonia. We conducted an adsorption experiment after supporting a transition metal on the FCC in order to improve the adsorption capacity. As a result, it was confirmed the best efficiency when supporting the copper nitrate 0.5% on the FCC. Based on this result, the experiment was conducted to determine the optimal mixing ratio with a high heating value and odor reducing function using Heavy oil fly ash and FCC. The optimal mixing ratio was 90% of Heavy oil fly ash and 10% of FCC. Furthermore, it was found that the most economical performance and highest odor reducing efficiency was achieved when the mixing ratio was 90% of dried sewage sludge and 10% of auxiliary fuel additives.

The principal hygienic problem caused by livestock industry is the odor exposed to farm workers. This study was performed to assess air cleaner efficiency for reducing odor through on-site evaluation. The concentration of ammonia and hydrogen sulfide, which are major odorous compounds generated from livestock building, were monitored by realtime direct recorder. The odor mixture was measured by air dilution method applying human noses of five panels. Their reduction efficiencies were represented by difference between initial concentration exhausted by non-treatment and concentration measured after treatment of respective control mechanism (water, germicide and plasma ion) of air cleaner. Mean levels of ammonia and hydrogen sulfide were 1.84 (SD:0.22) ppm and 76.83 (SD:1.37) ppb for non-treatment, 1.23 (SD:0.09) ppm and 59.07 (SD:2.68) ppb for wet scrubber (water), 1.08 (SD:0.03) ppm and 58.55 (SD:1.62) ppb for wet scrubber (germicide), and 0.96 (SD:0.03) ppm and 53.66 (SD:1.37) ppb for plasma ion, respectively. Mean dilution factors of odor mixture were 100 for non-treatment, 66.9 for wet scrubber (water), 144.2 for wet scrubber (germicide), and 66.94 for plasma ion, respectively. Based on the results obtained from on-site evaluation, ammonia and hydrogen sulfide showed the mean reduction efficiency of 40% and 25.7% compared with non-treatment process of air cleaner, respectively. In the case of odor mixture, the highest dilution factor was observed at wet scrubber (germicide) compared with other control mechanism of air cleaner.