• 한국대기환경학회지
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• 제1권1호
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• pp.83-92
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• 1985

In odrder to survey the emission level of air pollutants from diesel vehicles, was measured CO, HC, NOx and smoke of 4 types of domestic-use diesel engines under various conditions. The emission of CO, HC and NOx tested by 6-Mode test method and smoke emission by full load test met the permissible vehicle emission standard. Pollutant emission rates of diesel engines were different according to engine operating conditions, that is, engine load and engine speed. Generally, CO and HC was emitted more at low load and NOx at high load but the trend was quite different by the type of engines. In exhaust gas, $NO_2$ portion of NOx emission was high, specially at low speed and low load. The correlation equation between CLD(NOx) and NDIR(NO) method of nitrogen of nitrogen oxides analysis was y = 1.10x - 3.48 (y: CLD method) as a result of 6-mode test.

• 한국자동차공학회논문집
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• 제10권5호
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• pp.23-28
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• 2002

As the interest on the air pollution is gradually rising up at home and abroad, automotive industries have been working on the exhaust emission reduction from vehicles through a lot of approaches, which consist of new engine design, innovative aftertreatment systems, and using clean fuels. Methanol, ethanol, LNG, LPG, H2, reformulated gasoline are generally recognized as the clean fuel. Since the low price policy of government on LPG has expanded its vehicle market recently, there is concern of the exhaust emission of LPG vehicle. In this paper, we studied the value of LPG fuel as a clean fuel by comparing the results of the exhaust emission from LPG and Gasoline fueled vehicles, and discussed its limitation of LPG vehicle with mixer type as a fuel supply system. FTIR was used to understand the difference of exhaust emission components of LPG and Gasoline fueled vehicles.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권5호
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• pp.232-237
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• 2005

In this paper, we fabricated $CO_2$ gas sensor based on the MEMS infrared sensor and characterized its electrical and $CO_2$-sensing properties. The fabricated $CO_2$ gas sensor by MEMS technique has many advanges over NDIR(nondispersive) $CO_2$ sensor such as monolithic fabrication, very high selectivity on $CO_2$, low power consumption and compact system. Microbolometer by surface micromachining was fabricated for gas detector and $CO_2$ filter chip by bulk micromachining was fabricated for signal referencing. By using the proposed and fabricated gas sensor, we are expected to measure $CO_2$ concentration more accurately with high reliability.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2012년도 춘계학술발표회 초록집
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• pp.353-356
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• 2012

본 연구에서는 주택화재가 발생할 경우, 실내 바닥재로부터 발생하는 연소생성가스들 가운데 $CO_2$ 및 non-$CO_2$ 가스의 배출량을 정량적으로 분석하고자 하였다. 실험 방법으로는 주택에서 널리 쓰이는 타일카페트, 러버타일, PVC비닐석면, 데코타일, 모노륨 등 5가지 종류의 실내 바닥재를 대상으로 콘칼로리미터와 NDIR을 이용하여 연소에 따른 $CO_2$ 및 non-$CO_2$ 가스들에 대한 배출량에 대한 분석을 수행하였다.

• Bulletin of the Korean Chemical Society
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• 제22권12호
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• pp.1341-1344
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• 2001

Comparison of sulfur dioxide primary standard gases of the Korea Research Institute of Standards and Science (KRISS, Korea) and the National Physical Laboratory (NPL, UK) was performed. 100 ${\times}$10-6 mol/mol and 1,000 ${\times}$10-6 mol /mol primary standard gases (designated NPL S115 and S114, respectively) prepared gravimetrically and validated in NPL were used as transfer standards. Transfer standards were analyzed by NDIR sulfur dioxide analyzer and compared with KRISS PSM 112-03-624 and PSM 112-03-625 prepared gravimetrically. Adsorption corrected relative deviations of the primary standard gases were agreed to within 0.1%, and this agreement is within the expanded uncertainties (k = 2) of the primary standards at the two laboratories.

• 청정기술
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• 제25권1호
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• pp.40-45
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• 2019

본 연구에서는 도시고형폐기물 소각시설을 대상으로 2018년 8월 27일부터 2018년 10월 22일 동안 총 3회에 걸쳐 도시고형폐기물의 소각에 의해 발생되는 $N_2O$ 농도를 24시간 동안 연속적으로 측정하여 발생량과 배출특성을 조사하였으며, 배출가스 중 $N_2O$ 농도측정은 비분산 적외선 분석기(NDIR)를 이용하였다. $N_2O$ 배출특성을 조사한 결과 도시고형폐기물 소각시설의 $N_2O$ 발생량 및 발생농도는 폐기물의 성상 보다는 소각시설의 소각로 온도와 산소농도 같은 운전조건에 따라 상이하게 발생하는 것으로 판단된다. 도시고형폐기물 소각시설의 $N_2O$ 일일평균 발생농도는 53.6 ~ 59.5 ppm이며, 전체 평균농도는 55.6 ppm으로 측정되었다. 또한 $N_2O$ 농도를 이용하여 계산된 $N_2O$ 발생량은 $90.41{\sim}108.44kg\;day^{-1}$이며, 평균 발생량은 $98.05kg\;day^{-1}$로 조사되었다. 이러한 결과를 바탕으로 도시고형폐기물 소각시설의 $N_2O$ 배출계수를 산출한 결과 $1,066.13g_{N_2O}\;ton_{waste^{-1}}$로 생활폐기물의 Tier 2 방법으로 산출된 $N_2O$ 배출계수에 비해 약 20배 정도 높은 결과를 얻었다. 따라서, 폐기물 종류와 소각량을 이용한 폐기물 소각시설의 $N_2O$ 발생량 산출방식은 정확성에 대한 보완이 필요할 것으로 판단된다.

• 청정기술
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• 제26권4호
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• pp.293-303
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• 2020

세계보건기구에 따르면 대기오염은 건강에 대한 주요 위험원으로 대기오염으로 인해 매년 약 700만 명의 조기 사망이 발생하고 있다. 이산화황(SO2)은 대표적인 대기오염물질로 황 성분이 포함된 연료의 연소에서 다량 발생한다. SO2 발생량을 감소시키기 위해서는 대형 연소 환경에서 이를 실시간으로 정밀하게 측정하고 측정 값을 바탕으로 저감 설비를 최적화하는 과정이 필요하다. 이 논문에서는 미세먼지 전구물질인 SO2의 농도를 측정하기 위해 파장 가변형 다이오드 레이저 흡수 분광법 중 파장 변조 분광법을 이용하였다. 광원으로는 7.6 ㎛ 양자 폭포 레이저를 사용하였고 7623.7 ~ 7626.0 nm 사이의 64개 다중 광흡수선으로 SO2 농도 측정이 가능함을 증명하였다. 실험은 1 atm, 296 K에서 28, 76 m multi-pass cell을 사용하여 수행되었다. SO2 농도는 고농도(1000 ~ 5000 ppm)와 저농도(10 ppm 이하)로 두 종류로 실험 하였다. 추가적으로 가스 셀 외에 레이저가 지나가는 경로에 질소를 채워 대기 중의 H2O가 SO2 측정에 미치는 영향을 확인하였다. SO2는 3 ppm까지 측정하였고 측정된 SO2 농도는 전기 화학식 센서와 NDIR 센서 측정 결과와 비교되었다.

• 한국대기환경학회지
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• 제26권5호
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• pp.499-506
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• 2010

Recently, a great deal of attention have been directed to the use of alternative fuels as a means to reduce vehicular emissions. As one of the promising alternative fuels, bio-diesel has advantages of a wide adaptability without retrofit of diesel engine. It is also effective enough to reduce CO, THC, $SO_x$, polycyclic aromatic hydrocarbons (PAHs) and PM. In this study, we investigated the emission characteristics of biofuels between different operating conditions, i.e., engine speed (1,400 rpm and 2,300 rpm), engine load (10% and 100%), bio-diesel blending (BD0, BD5 and BD20), and recirculation (EGR) rate of exhaust gas (0% and 20%). Relative performance of the system was evaluated mainly for the greenhouse gases ($CH_4$, $N_2O$ and $CO_2$). In addition, emission characteristics of ND-13 mode were also tested against both greenhouse gases and other airborne pollutants under emission regulation. The relative composition of bio-diesel has shown fairly clear effects on the emission quantities of CO, THC, and PM emission, although it was not on $NO_x$ and greenhouse gases. EGR rate has shown trade-off characteristics between $NO_x$ and PM.

• 센서학회지
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• 제27권5호
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• pp.294-299
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• 2018

This article describes the output properties of non-dispersive infrared carbon dioxide($CO_2$) sensors resulting from the changes in ambient temperatures. After the developed sensor module was installed inside the gas chamber, the temperature was set to 267 K, 277 K, 300 K, and 314 K, and the concentrations of $CO_2$ gas were increased from 0 to 5,000 ppm. Then, the output voltage at each concentration was obtained. Through these experimental results, two observations were made. First, both the $CO_2$ sensor and the reference sensor showed an increase in the output voltages as the temperature rose from 0 ppm, Second, the full scale outputs of the $CO_2$ sensor grew as the temperature increased. The output characteristics were analyzed based on two factors: change in the radiant energy of the infrared light source and change in the absorptivity of $CO_2$ gas according to the ambient temperature. Additionally, temperature compensation methods were discussed.

• Advances in environmental research
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• 제7권2호
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• pp.73-85
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• 2018

The anaerobically digestion and agricultural application of organic wastes was conducted using food wastes and cow dung. Twenty kilograms each of the feed stocks was added into two 30 liters-capacity batch digesters. The anaerobic digestion was carried out within a temperature range of $25-31^{\circ}C$ for a retention time of 51 days. The results showed a cumulative gas yield of 5.0 bars for food waste and no gas production for cow dung within the retention time. Bacteria such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Proteus vulgaris and Clostridium sp were isolated. Fungi isolated included Aspergillus niger, Aspergillus nidulan, Trichophyton rubrum and Epidermophyton flocossum. The non-dispersive infrared (NDIR) analysis of the biogas produced confirmed that the gas consisted of $CH_4$, $CO_2$ and $H_2$. Statistical analysis revealed there was no significant correlation between temperature and biogas produced from the organic wastes (r= 0.177, p = 0.483).The organic wastes from the biogas production process stimulated maize growth when compared to control (soil without organic waste) and indicated maximum height. The study therefore reveals that food waste as potential substrates for biogas production has a moderate bio-fertilizer potential for improving plant growth and yield when added to soil.