• 한국대기환경학회지
• /
• 제29권6호
• /
• pp.757-772
• /
• 2013

In this study, a combination of sorbent tube (ST)-thermal desorption (TD)-gas chromatography (GC)-mass spectrometry (MS) was used for quantitative analysis of liquid phase standards of 10 BVOC ((1) (+)-${\alpha}$-pinene, (2) (+)-${\beta}$-pinene, (3) ${\alpha}$-phellandrene, (4) (+)-3-carene, (5) ${\alpha}$-terpinene, (6) p-cymene, (7) (R)-(+)-limonene, (8) ${\gamma}$- terpinene, (9) myrcene, and (10) camphene). The results of BVOC calibration yielded comparatively stable pattern with response factor (RF) of 23,560~50,363 and coefficient of determination ($R^2$) of 0.9911~0.9973. The method detection limit (MDL) of BVOC was estimated at 0.03~0.06 ng with the reproducibility of 1.30~5.13% (in terms of relative standard error (RSE)). Emissions of BVOC were measured from four types of fruit samples ((1) tangerine (TO), (2) tangerine peel (TX), (3) strawberry (SO), and (4) sepals of strawberry (SX)). The sum of BVOC flux (${\sum}flux$ (BVOC) in ng/hr/g) for each sample was seen on the descending order of (1) TX=291,614, (2) TO=2,190, (3) SO=1,414, and (4) SX=2,093. If the results are compared between the individual components, the highest flux was seen from (R)-(+)-limonene (265,395 ng/hr/g) from TX sample.

• Journal of the Korean Wood Science and Technology
• /
• 제35권5호
• /
• pp.24-37
• /
• 2007

The Korean Ministry of Environment started controlling indoor air quality (IAQ) in 2004 through the introduction of a law regulating the use of pollutant emitting building materials. The use of materials with formaldehyde emission levels above $1.25 mg/m^2{\cdot}h$ (JIS A 1901, small chamber method) has been prohibited. This level is equivalent to the $E_2$ grade ($>5.0mg/{\ell}$) of the desiccator method (JIS A 1460). However, the $20{\ell}$ small chamber method requires a 7-day test time to obtain the formaldehyde and volatile organic compound (VOC) emission results from solid building interior materials. As a approach to significantly reduce the test time, the field and laboratory emission cell (FLEC) has been proposed in Europe with a total test time less than one hour. This paper assesses the reproducibility of testing formaldehyde and TVOC emissions from wood-based composites such as medium density fiberboard (MDF), laminate flooring, and engineered flooring using three methods: desiccator, perforator and FLEC. According to the desiccator and perforator standards, the formaldehyde emission level of each flooring was ${\le}E_1$ grade. The formaldehyde emission of MDF was $3.48 mg/{\ell}$ by the desiccator method and 8.57 g/100 g by the perforator method. To determine the formaldehyde emission, the peak areas of each wood-based composite were calculated from aldehyde chromatograms obtained using the FLEC method. Formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde and benzaldehyde were detected as aldehyde compounds. The experimental results indicated that MDF emitted chloroform, benzene, trichloroethylene, toluene, ethylbenzene, m,p-xy-lene, styrene, and o-xylene. MDF emitted significantly greater amounts of VOCs than the floorings did.

• 한국환경과학회지
• /
• 제29권5호
• /
• pp.559-573
• /
• 2020

The purpose of this study analyzed the overview of corrugated cardboasrd manufacturing industry and then provide direction for improvement. The BREF (BAT reference document) is an important reference for licensees and officer, including the best available techniques for the industry and achievable environmental performance, technical characteristics, and economic information. In the corrugated cardboard manufacturing process, wastewater pollutants are generated throughout the production process, and water is used in the dissociation and aging process. Atmospheric emissions are mostly generated by steam production from boilers and incinerators for the dry process. SO₂, NOx, CO₂, CO, HCl, dust, VOC, and odor were common. In the EU-BREF (European union BAT reference documents) BAT for wastewater have taken up a relatively large proportion. Items of water pollutants in wastewater were common in COD, BOD, N, P, SS, and however EU-BREF had different pollutants such as AOX and salt compared to K-BREF. In order to improve the quality of the K-BREF, it is necessary to devise basic data research method and data acqusitiom method. Consideration should be given to additional environmental management techniques that reflect the emissions characteristics of the corrugated cardboard manufacturing process. In addition, further research is needed to develop methodologies for selecting BATs considering environmental and economic feasibility.

• 설비공학논문집
• /
• 제15권1호
• /
• pp.40-49
• /
• 2003

This study has been conducted to identify and quantify the emissions of Volatile Organic Compounds (VOCs) from a new carpet. The carpet sample consists of polypropylene cushion and latex backing. The VOCs have been sampled on sorbent tubes and analyzed by thermal desorption unit and GC/MSD. For over 240 hours, concentration of VOCs has been measured in a small chamber made of stainless steel. With the measured data, emission factor and mass balance have been considered. The experiments have been conducted in accordance with ASTM D5116-97. The carpet has emitted a variety of VOCs, but in this study, 7 VOCs compounds have been considered： chlorobenzene, ethylbenzene, styrene, isopropylbenzene, bromobenzene, 2-chlorotoluene, and 1,2,3-trimethylbenzene. The results show that the concentrations of VOCs and the emission factors have exponentially decayed from relatively high level to low level with time. The gradients of the concentration of VOCs and emission factors are different for various components. It is found that styrene, 2-chlorotoluene are emitted more than others with higher concentrations.

• 한국환경보건학회지
• /
• 제40권6호
• /
• pp.477-483
• /
• 2014

Objectives: This study was carried out to investigate the characteristics of odors emitted from sewage in a sanitary sewer and its outlets. Methods: The concentration of mal-odorous sulfur was analyzed by gas chromatograph, and odor intensity was estimated by an on-site sensory test. Odor intensity calculated from instrumental analysis results was compared with odor intensity observed at field. Results: As a results, the concentration of $H_2S$ ranged from 2.4 ppb to 5,889 ppb (average 703 ppb), while $CH_3SH$, $(CH_3)_2S$, and $(CH_3)_2S_2$ showed from 10 ppb to 554 ppb (average 119 ppb) and from 20 ppb to 332 ppb (average 70 ppb) and from 2.7 ppb to 8.1 ppb (average 5 ppb) individually. Average odor intensity observed in the field was degree three. Odor intensity calculated from sulfur compound concentration was confirmed as similar to the observed odor intensity because the coefficient of variance between the observed and the calculated intensities was less than one. Conclusion: It was expected that the results of this study will be helpful to design a deodorizing device to reduce odor emissions from sewerage facilities in the future.

• Asian Journal of Atmospheric Environment
• /
• 제8권4호
• /
• pp.192-201
• /
• 2014

A comprehensive profile of volatile organic compounds (VOCs) in public spaces is needed for interpreting indoor air measurements. Seasonal differences in profiles are critical for epidemiological study and risk assessment. The purposes of this study were to establish profiles for individual VOCs in 50 indoor public places in Korea and to determine seasonal variations in their concentrations. Air samples were taken during working hours. Seventy-two of the 91 targeted VOCs were identified using multiple standards. Six VOCs detected in all summer and winter samples were toluene, acetone, m,p-xylenes, ethylbenzene, benzene, and styrene. In summer, methyl ethyl ketone and 1-butanol were also found in all samples. In both seasons, the dominant indoor VOCs were toluene, m,p-xylenes, ethylbenzene, acetone, and isopropyl alcohol. Other chemicals associated with gasoline emissions were dominant in summer. Limonene was dominant only in winter due to the consumption of tangerines. The nine VOCs with the highest concentrations comprised 64.8% and 49.6% of the TVOC in summer and winter, respectively. Comparing two types of adsorbent tube, a single adsorbent tube with Tenax-TA had similar detection performance as a double adsorbent tube with Tenax and Carbotrap.

• 한국대기환경학회지
• /
• 제14권2호
• /
• pp.95-106
• /
• 1998

Volatile organic compounds (VOCs) from Ca to C9 were investigated with nine ambient air samples collected in April 26, August 17, 1996 and January 23, 1997 in a Seoul site. On each sampling day, three 2-hr integrated canister samples were collected in early morning, early afternoon and late afternoon, respectively to study temporal . variation of VOCs. Most of VOC species showed diurnal variation with higher concentrations in the early morning and lower concentrations in the afternoon. The concentrations of light alkanes were high, probably due to the emission from liquefied petroleum gas (LPG) and evaporation of gasoline. Especially, the concentration of propane was the highest in the morning samples. The concentrations of propane, ethylene, acetylene, and toluene were prominent in their hydrocarbon groups, respectively. These components were the main source of car exhaust, gasoline evaporization, LPG, or solvent usage.

• 한국환경과학회지
• /
• 제19권1호
• /
• pp.1-8
• /
• 2010

Only limited information is available on the measured exposure levels of residents according to the construction age of apartments. As such, present study was conducted to measure and to compare the bedroom, living-room, and outdoor air levels of MTBE and benzene, toluene, ethyl benzene and m,p-xylene(BTEX) in both newer and older apartments. For both newer and older apartments, all the compounds except for MTBE showed significantly higher levels in bedrooms or living-rooms as compared to the outdoor concentrations. The ratio of bedroom or living-room median concentration to outdoor concentration was close to 1 for MTBE, whereas it was larger than 1 for other target compounds. It was also found that the bedroom and living-room appeared to have similar indoor sources and sinks for BTEX, but not for MTBE. The median concentration ratios of the newer apartments to the older apartments ranged from 1.63 to 1.81, depending upon the compounds. In contrast, the MTBE concentrations did not differ significantly between the newer and older apartments, thereby suggesting that although newer buildings could emit more VOCs, this is not applicable to all VOCs. Conclusively, the findings of present study should be considered, when designing exposure studies associated with VOC emissions in buildings and/or managing indoor air quality according to construction age of buildings.

• Molecules and Cells
• /
• 제41권8호
• /
• pp.724-732
• /
• 2018

Plant defence responses to various biotic stresses via systemic acquired resistance (SAR) are induced by avirulent pathogens and chemical compounds, including certain plant hormones in volatile form, such as methyl salicylate and methyl jasmonate. SAR refers to the observation that, when a local part of a plant is exposed to elicitors, the entire plant exhibits a resistance response. In the natural environment, plants are continuously exposed to avirulent pathogens that induce SAR and volatile emissions affecting neighbouring plants as well as the plant itself. However, the underlying mechanism has not been intensively studied. In this study, we evaluated whether plants "memorise" the previous activation of plant immunity when exposed repeatedly to plant defensive volatiles such as methyl salicylate and methyl jasmonate. We hypothesised that stronger SAR responses would occur in plants treated with repeated applications of the volatile plant defence compound MeSA than in those exposed to a single or no treatment. Nicotiana benthamiana seedlings subjected to repeated applications of MeSA exhibited greater protection against Pseudomonas syringae pv. tabaci and Pectobacterium carotovorum subsp. carotovorum than the control. The increase in SAR capacity in response to repeated MeSA treatment was confirmed by analysing the defence priming of the expression of N. benthamiana Pathogenesis-Related 1a (NbPR1a) and NbPR2 by quantitative reverse-transcription PCR compared with the control. We propose the concept of plant memory of plant defence volatiles and suggest that SAR is strengthened by the repeated perception of volatile compounds in plants.

• 실내환경 및 냄새 학회지
• /
• 제17권4호
• /
• pp.396-403
• /
• 2018

In this study, volatile organic compounds (VOCs) emitted from printing industries were analyzed, and an inorganic adsorbent, ${\gamma}-alumina$, was selected for the effective control of the VOC emissions. Printing processes commonly require inks, thinners, and cleaners, and they were mixed organic solvents containing aromatic compounds, ketones, and alcohols. Therefore, toluene, methyl ethyl ketone (MEK), and isopropyl alcohol (IPA) were selected as model compounds for this study. The adsorptive properties using ${\gamma}-alumina$ were determined for the model compounds. Both batch isotherm and continuous flow column tests demonstrated that the adsorption capacity of MEK and IPA was 3~4 times higher than that of toluene. The column test performed at an inlet toluene concentration of 100 ppm showed that an 80% breakthrough for toluene was observed after 3 hours, but both MEK and IPA were continuously adsorbed during the same time period. A numerical model simulated that the ${\gamma}-alumina$ could remove toluene at a loading rate of 0.4 mg/min only for a 4-hour period, which might be too short of a duration for real applications. Consequently, lifetime enhancement for ${\gamma}-alumina$ must be implemented, and ozone oxidation and regeneration would be feasible options.