An odor is referred to or described as an unpleasant smell that creates a disagreeable atmosphere and may impinge on the quality of life of people. Most of the odors that stimulate the human sense of smell and engender feelings of discomfort and disgust are odors mixed with various chemicals substances. Among designated odor substances, acetaldehyde, propionaldehyde, butyraldehyde, n-valeraldehyde, and iso-valeraldehyde may cause an irritating and sour sensation and give rise to headache, dizziness, vomiting, and unconsciousness. These aldehyde substances are mainly discharged in high concentrations from food chemicals, petrochemicals, and printing industry sources. The odor control technologies applied to prevent odors from aldehydes are absorption, adsorption, as well as biological methods and combustion methods. The threshold concentrations of aldehydes are low so that odors can be easily experienced even at very low concentrations. It is not easy to control aldehydes due to their particular physicochemical properties and because aging and poor management of the odor prevention technology is usually only available. In this study, trends with regard to research efforts on the development of technology that is effective in treating aldehydes were summarized.

본 연구는 전자 센서를 이용하여 다양한 추출방법에 따른 무 추출물들의 향미 특성을 조사하였다. 무의 신맛은 무 흰색 부위의 열수 추출물이 6.9의 센서 값을 나타내어 가장 높았다. 신맛은 8.0의 센서 값을 나타내어 무 초록색 부위의 콜드 브루 추출물이 가장 높았다. 감칠맛은 무 흰색 부위의 열수 추출물이 8.3의 센서 값을 나타내어 가장 높았다. 단맛은 무 초록색 부위의 콜드 브루 추출물이 6.8 의 센서 값으로 가장 높은 값을 나타내었고, 쓴맛은 무 초록색 부위의 고온 가압 추출물이 7.5의 센서 값으로 가장 높은 값을 나타내었다. 전자코를 이용하여 무 추출물들에서 총 16개의 휘발성 향기성분을 확인하였다. 무 추출물 속 휘발성 향기성분들 중 methanethiol이 주요한 향기성분으로 확인되었다. 본 연구에서 확인된 결과들은 무 추출 물의 향미 특성에 대한 기초 연구 자료로 활용될 수 있을 것으로 판단된다.

The concentrations of volatile organic compounds (VOCs) and odor-inducing substances were measured using selected ion flow tube mass spectrometers (SIFT-MS) and a drone equipped with an air quality monitoring system. SIFT-MS can continuously measure the concentration of VOCs and odor-inducing substances in realtime without any pre-treating steps for the sample. The vehicle with SIFT-MS was used for real-time measurement of VOC concentration at the site boundaries of pollution sources. It is possible to directly analyze VOCs concentration generated at the outlets by capturing air from the pollution sources with a drone. VOCs concentrations of nine spots from Banwol National Industrial Complex were measured by a vehicle equipped with SIFT-MS and were compared with the background concentration measured inside the Metropolitan Air Quality Management Office. In three out of the nine spots, the concentration of toluene, xylene, hydrogen sulfide, and methyl ethyl ketone was shown to be much higher than the background concentration. The VOCs concentrations obtained using drones for high-concentration suspected areas showed similar tendencies as those measured using the vehicle with SIFTMS at the site boundary. We showed that if both the drone and real-time air quality monitoring equipment are used to measure VOCs concentration, it is possible to identify the pollutant sources at the industrial complex quickly and efficiently check sites with high concentrations of VOCs.

We developed a wet scrubber by applying cyclone flow to the gas flow and using a spiral filter structure. While the size of a new scrubber was about half that of a conventional scrubber, the device showed relatively high efficiency in pollutants removal such as particulate matter and compounds inducing odor. The new scrubber installed in a plating industry showed a higher removal efficiency of about 5% for dust, about 23% for hydrogen chloride, and about 23% for sulfur dioxide compared to the conventional scrubber. Plurality of tubes in the spiral filer housing are arranged to be vertically shifted from each other. Because the upward residual gas does not directly rise vertically, the residence time of gas between the filter plates is extended. Thus, the purification efficiency of the pollutants was enhanced in the new scrubber. In addition, the new scrubber developed in this study is more cost effective because the cost saving in manufacturing it compared with a conventional scrubber increases with increasing the size of equipment. It is expected that a scrubber with better dust collecting efficiency can be obtained by carrying out a study in connection with facilities capable of controlling acidity of washing water.

본 연구는 2017년 4월부터 10월까지 북한강 수계 3개의 연속댐 (의암호 (UA), 청평호 (CP), 팔당호 (PD))의 미소생물 군집과 이취미 농도와 관계를 알아보기 위해 환경요인, 이취미 물질, 미소생물 군집 등을 조사하였다. 3개 저수지의 박테리아 군집은 주로 Actinobacteria와 Betaproteobacteria가 우점 분류군으로 나타났으며, 계절성은 나타나지 않았다. 식물플랑크톤 군집은 봄철, 규조류 및 은편모조류 여름철 남조류, 가을철 규조류 및 은편모조류 순서로 우점하는 계절성을 보였으며, 북한강 수계에서 출현한 남조류는 Dolichospermum spp., Microcystis aeruginosa, Pseudanabaena spp. 속이 우점 출현하였다. 북한강 수계에 출현한 미소생물 중 이취미 물질을 발생하는 분류군은 Actinobacteria와 남조 Anabaena, Pseudanabaena 속 등이며, 이취미 물질인 Geosmin과 2-MIB가 높게 나타났을 때, 높은 현존량으로 출현하였다. 미소생물과 이취미 물질의 상관관계는 Actinobacteria의 경우 2-MIB (r=0.491, p<0.01)와 유의한 상관성을 나타냈으며, 남조류의 경우 geosmin (r=0.381, p<0.05), 2-MIB (r=0.386, p<0.05)와 유의한 상관성을 나타냈다. 따라서, 북한강 수계에서 나타나는 이취미 물질은 Actinobacteria 및 남조류의 출현과 직접적인 관계가 있을 것으로 사료되며, 남조류 미출현 시 발생하는 높은 농도의 이취미 물질은 Actinobacteria가 생성하는 것으로 판단된다.

There has been growing concern over the emissions of formaldehyde and VOCs from automotive interior materials, as these could have an important impact on the in-vehicle air quality (IVAQ) of automotive vehicles. Odor, the components of which may include VOCs, refers to the automotive interior smell emitted directly or indirectly from any part of an automotive interior, based on human olfactory senses and a comfort evaluation of vehicle quality. The objective of this paper is to compare the instrument analysis with the sensory characteristics of an odor using GC/MS/Olfactometry. From the test, it was possible to identify the cause of odor, which can be difficult to distinguish among multiple odors, through the simultaneous performance of instrumental analysis and sensory evaluation.

There has been growing concern over the emissions of formaldehyde and VOCs from automotive interior materials, as these could have an important impact on the in-vehicle air quality (IVAQ) of automotive vehicles. Odor along with VOCs refers to the automotive interior smell emitted directly or indirectly from any part of an automotive interior, based on human olfactory senses and a comfort evaluation of vehicle quality. The objective of this paper is to compare the odor intensity using GC/MS analysis method and odor sensory test in accordance with ISO 12219-2. For the compounds having low odor threshold value and high VOC concentration, it was found that there was the same tendency in each field of odor whether the instrument analysis method or the odor sensory test method was used.

This study compared the stability of odor compounds in three different types of polymer sampling bags. Tedlar, PET (polyethylene terephthalate) and aluminized polyester bag were used. A sample was collected from the interior of a new automobile which was parked in an outdoor parking lot. It was found that the Tedlar bag showed lower stability for odor active compounds than the PET bag. Meanwhile, the PET bag had good stability for odor compounds compared to the aluminized polyester bag. The PET bag showed a stability for the molecules smaller than toluene that was comparable to the canister, but showed a lower recovery for molecules bigger than C7. The FID signal of the sample in the PET bag was reduced by 1.7times after 3days storage compared to 24 h storage. The number of detected odor active compounds was reduced by half, and odor intensity was also decreased by 2~3 degrees. Considering the factors of repeated use, usability and price, a PET bag covered with a black plastic bag was the most appropriate approach for odor sampling in an automobile interior.

The objective of this experiment was to evaluate the effect of Chamaecyparis obtus extract to reduce odor emissions released from the swine feeding operations. Finisher pigs [Landrace × (Yorkshire × Duroc)] with an initial body weight averaging 50 kg were housed separately in two rooms with eighty eight pigs in each room at a swine feeding operation site. C. obtus extract was sprayed in the room by ceiling sprayer for one minute at twice per day during two months. Concentrations of odorous compounds from air in the room of the swine feeding operation were analyzed at four times during two months. Levels of butyric acid, valeric acid, i-butyric acid, ivaleric acid, skatole, methylmercaptan, and trimethylamine tended to decrease in C. obtus extract spray treatment group compared to the non-spray treatment group (P > 0.05). Odor activity values of butyric acid, valeric acid, skatole and trimethylamine were higher than other odorous compounds and decreased by 72%, 76%, 54% and 20%, respectively, in C. obtus extract spray treatment group compared to the non-spray group. Taken together, C. obtus extract showed an odor reducing capability in the air of a swine feeding operation suggesting that it possesses anti-bacterial properties as well as having a dust removal and masking effect.

This study was performed to measure the concentration of odorous compounds and dilution ratio values at each part of the anaerobic digester process with composting facilities using swine manure and food waste. Complex odors, ammonia, volatile fatty acids and sulfur compounds were measured at each part of the process. Complex odors measured during swine manure storage, food waste storage and in the digested liquid tank, were 35,312 Odor Unit(OU), 39,086 OU and 17,733 OU, respectively. The odor contribution index was calculated by the concentration of odorous compounds during each process divided by the threshold limit. As a result, the major odorous compound that appeared during swine manure storage, food waste storage and in the digested liquid tank was hydrogen sulfide. On the other hand, the major odorous compound in the other processes was ammonia. The overall average concentrations of ammonia were highest in the digested liquid tank(337 ppm) and the separated liquid tank(131 ppm). Wastewater treatment process(10.9 ppm) and deodorization process(11.6 ppm) revealed the lowest concentration of ammonia. The overall average concentration of total volatile fatty acids(TVFAs) was 102.8 ppb during food waste storage and among the TVFAs, the main element was propionic acid(66.1 ppb). Sulfur compounds were only detected during swine manure storage, food waste storage and in the digested liquid tank. The dominant sulfur compound was hydrogen sulfide during swine manure storage(96.3 ppm) and methyl mercaptan during food waste storage(17.7 ppm) and dimethyl sulfide during food waste storage(34.5 ppm).

In this study, leachate treatment facility (outlet, facility inside) and landfill sections (vent systems, landfill surface)of nine landfills is being buried in korea were studied emission characteristics of odor compounds. Air dilutionvalue in ventpipes of landfill section was generally highest and was more 3 times higher than emission standard(air dilution value of facilities outlet : 500) in Daejeon, Tongyeong, and Busan landfill. Outlet of leachate treatmentfacilities in Tongyeong and Daegu landfill, in case, was higher respectively 20 times, 6 times than other landfills,commonly show that a large contribution to the odor of hydrogen sulfide. In case of ordor emission rate, ammoniaand hydrogen sulfide were surveyed to comprise a high rate for odor emission rate. Odor emissions based onlandfill scale, large landfill (Sudokwon) and small landfills (Yeosu, Chuncheon, Chungju) is low in odor emissionsper unit area, whereas medium landfill (Busan, Daejeon, Daegu) was estimated to be high odor emissions. In caseof large landfill, leachate treatment facilities is management in good condition and discharged odor emission oflandfill sections was low into ambient air. In case of small landfill, decay gases and leachate is few. Thereforeodor emissions is fewer than estimated medium landfill. In case of medium landfill, management condition ofleachate treatment facility was in poor and landfill sections was under not stabilization stage. Thus, mediumlandfills was identified that needs to be intensive care.

도시지역 합류식 하수배제 설비인 우수받이 및 하수관거, 정화조 등에는 유기성 고형 물이 퇴적되기 쉬우며, 유기성 퇴적물이 부패되는 과정에서 고농도의 황계열 악취물질이 발생한다. 본 연구에서는 전기산화방식을 이용하여 유기성 퇴적물 내에 용존된 악취물질 및 전구물질을 저감시켜, 하수관거에서 기상으로 배출되는 악취 문제를 해결하고자 하였다. 실험실 규모의 밀폐된 회분식 반응기에 하수슬러지(COD 기준 8,000 ~ 28,000 mg·L-1)를 투입하고, 발생되는 악취물질 농도와 악취발생특성을 조사하였다. 여기에 전기산화시스템 을 적용하여 황계열 악취물질과 전체 유기물의 산화 및 분해실험을 진행하였다. 전기산 화 실험을 진행한 결과, 밀폐된 반응기의 기상에서 450 ppm의 고농도로 발생한 황화수 소가 반응 30분 이내에 검출한계 이하까지 제거되었으며, 메틸머켑탄과 디메틸설파이드 는 85% 이상 제거되었다. 투입된 전기에너지당 황계열 악취물질의 제거율은 최대 0.33 mg-S·kJ-1로 나타났다. 또한 1시간의 반응기간 동안 회분식 반응기 내에서 황계열 악취물 질 뿐만 아니라 고농도 퇴적물에 함유된 전체 유기물 농도가 56% 감소하여, 전기산화시 스템이 악취를 유발하는 유기성 전구물질을 동시에 저감하는 효과를 나타내었다. 결과적 으로 최소한의 전기에너지를 이용하여 하수관거 퇴적 유기물에 의한 악취문제를 해결할 수 있을 것으로 기대된다

본 연구에서는 공공하수처리시설의 효율적인 관리방안 제시를 위하여 2008년~2010년까지 28개소의 공공하수처리시설에 대하여 복합악취와 지정악취물질(22종)을 대상으로 악취실태조사 및 원인분석을 실시하였다. 조사결과 전처리 공정과 슬러지 처리공정에서 주로 고농도의 악취가 발생되고 있었으며, 황화수소와 메틸머캅탄 등의 황화합물류가 주요 악취원인물질로 조사되었다. 공공하수처리시설에서 발생되는 악취는 유입수의 성상에 따라 차이가 있으며, 유입수에서의 복합악취는 67배~66,943배, 황화수소는 ND~66.87 ppm으로 조사되었다. A 하수처리시설 유량 조정조에서의 복합악취와 황화수소는 교반시 각각 3,000배, 6.23 ppm, 비교반시 각각 300배, 0.20 ppm으로 조사되었다. 유입 분배조와 생슬러지 분배조는 하수와 슬러지 이송 파이프 라인의 낙차에 의해 내부에 양(+)압이 형성되므로 파이프 라인의 연장과 악취포집설비를 정상적으로 설치․운영하여 내부를 음(-)압 상태로 유지할 필요가 있다.

This study aims to evaluate the relationship with the concentration and odor intensity using the odor sensory method for 4 types of sulfur compounds, ammonia, and trimethylamine. For the measurement, 13 panelists were selected by several criteria through a panel test. Panelists chosen for their closely similar sensitivities provide more reproducible values. The estimation showed that the correlation of the concentration with odor intensity for the 6 compounds can be reasonably expressed by the equation I=Aㆍlog C+B (I: Odor Intensity, C: material concentration, A: material constant, B: constant). The result of this study is suggested to be used as a base data for research on measures to improve the regulation standards for complex odor concentration on site boundary in operation, as well as a correlation between the concentration and odor intensity for the designated foul odor substances, and their characteristics.

The occurrence of objectionable tastes and odors in drinking water is a common and widespread problem. The most troublesome odors are usually those described as muddy or earthy-musty. Two organic compounds which have been implicated as the cause of earthy-musty odor problems in water are geosmin and 2-Methylisoborneol. These earthy-musty organics have been shown to be metabolites of actinomycetes and blue green algae. The purpose of this paper is to describe adsorbability in removing these two oder causing compounds(geosmin and 2-MIB) upon various conditions like pH variation, adding humic acid and different activated carbon. The conclusion of this study are as followings. In batch test, carbon dosage is 10mg/100ml for geosmin and 15mg/100ml for 2-MIB. Both were in equilibrium state after 60 hours. In model simulation, F-P model described experiment data and modelling data appropriately in geosmin but F-S model not. In case of 2-MIB, models didn't describe relation between experiment and modelling data well. Two causative agents of earthy-musty odor compounds, geosmin and 2-MIB, are strongly adsorbed by activated carbon either coconut or brown. There appears to be no effect of pH (3,7,9) on adsorption of these two organics. Activated carbon proved to be more effective for removing geosmin than for removing 2-MIB. When activated carbon is. used in removing these two organics, the removal of these appeared to be adversely affected by back ground organic compounds, such as humic substances, due to competitive adsorption.

The volatile odor compounds emitted form a stuffing agent production process were quantified by ATD and GC-MS, and then odor causing compounds were identified by the method of EOI using each TLV. As the results, 72 odor compounds were detected and total concentration was turned up 87.6 ppmv level. In these compounds, aldehyde group is higher 45.49 ppmv than others group, the next is turn up the order of aliphatics, alcohols, esters, ketones. The EOA of aldehyde group show up 101,720 and 97.2%, respectively, the odor causing compounds were identified each of odor 2-Octenal 28.31%, Hexanal 24.06%, Valeraldehyde 16.07%, Butyraldehyde 9.69%, Heptanal 4.97%, Propionaldehyde 4.64%, Acetaldehyde 3.31%. The TLVs of 7 major odor compounds are lower value level of 0.001∼0.0001 ppmv, odor causing even in trace level. We need to be concerned with reduction of aldehyde compounds in the odor problem by a stuffing agent production process or ironing process of the textile containing a stuffing agent.

The purpose of this study was to obtain the basic data needed to identify the impact of the odor, emitted from the Ochang Scientific Industrial Complex area on the surrounding residential areas by measuring and confirming odor compounds. The analysis showed that complex odors were diluted from around 4 to 1. The offensive odor measurement results showed that among the sites, site 1 was highest in sulfur compounds, site 2 was highest in toluene, site 3 was highest in trimethylamine, and site 4 was highest in buthylaldehyde. It cannot be decided to be odor-causing compounds for higher odor concentration because each odor substance has a different odor threshold value. According to the odor contribution analysis for each site, site 1, site 2, and site 4 contained high buthylaldehyde concentrations, and site 3 had a high level of trimethylamine. It could be determined that highly evaluated substances were main causes to result in substance for each site.

As a typical example of simultaneous analysis of the odorous compounds, the volatile organic compounds from inventory sources in Seongseo industrial area were concentrated and analyzed with thermal desorber/GC/ MSD, and major malodorous compounds were estimated. Odor intensity and odor concentration was analyzed simultaneously During a period from November in 2002 to December in 2003, this study was conducted to evaluate malodor emission characterization in major treatment facilities. The major components were Dimethyl sulfide, Dimethyl disulfide, Methyl mercaptane, Ammonia, Benzene, Toluene, m,p-xylene, o-xylene, Styrene, 1,2,4- T.M.B and 1,3,5-T.M.B. Among the six major inventory sources, the odor unit concentration of Night-soil disposal facilities was the highest, 669～2344 ou/m3.