• 자원리싸이클링
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• 제25권2호
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• pp.17-24
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• 2016

본 연구에서는 폐소형가전 재활용을 위한 파쇄, 선별 및 회수 공정에 대해 전과정평가(Life Cycle Assessment, LCA) 기법을 활용하여 환경영향을 분석하였다. 폐소형가전 파쇄, 선별 및 회수 공정의 지구온난화(Global Warming Potential, GWP)에 대한 환경영향은 $1.29E+02kg\;CO_2-eq./kg$으로 분석되었으며, 가중치 결과 1.17E-02Pt로 지구온난화(GWP)에 대한 환경영향의 경우 전체 환경영향의 약 57.1%, 자원고갈(ADP) 약 35.4%, 광화학산화물 형성(POCP) 약 4.8% 등이었다. 유용자원 1톤을 선별/회수하는 공정의 지구온난화(GWP)에 대한 환경영향은 플라스틱류 즉, ABS 33.7%, PP와 HIPS가 각각 약 16.8%, 철금속류 약 9.4% 등으로 플라스틱류의 선별/회수공정의 경우 지구온난화에 대한 환경영향이 가장 큰 것으로 분석되었다. 또한, 유용자원을 회수하여 재활용하므로서 신재 생산보다 지구온난화(GWP) 환경영향에 대하여 약 $2.73E+04ton\;CO_2-eq./ton$의 환경회피 효과가 발생하였으며, 이는 연간 약 48,236.4천원의 경제적 효과가 발생하는 것으로 조사되었다. 폐소형가전으로부터 유용자원을 효율적으로 재활용할 경우 지구온난화(GWP)에 대한 환경영향을 줄여 기후변화 대응에 효과적일 것으로 사료된다.

• 한국포장학회지
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• 제29권3호
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• pp.181-193
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• 2023

In this study, we conducted a comparative life cycle assessment (LCA) of two different products, considering reusable and single-use packaging for fresh food distribution. For reusable packaging, we utilized expanded polyethylene (EPE), while for comparison, a disposable box made of widely used expanded polystyrene (EPS) was selected. We comprehensively analyzed the environmental impacts of production, transportation, reprocessing (for reused boxes), and disposal across 18 impact categories. Upon analyzing the actual reuse of 300 rounds of fresh food, the cumulative global warming potential (GWP) values for the EPE box were found to be 280.21 kg carbon dioxide (CO₂) eq, demonstrating a significant 75% reduction compared to those of the EPS box. Furthermore, it was observed that the GWP values for the EPE boxes became equivalent to those of the EPS boxes after 12 rounds of reuse. In conclusion, reusable packaging shows substantial potential to contribute to the reduction of environmental burdens, aligning well with global environmental requirements for sustainable food distribution and related industries.

• 한국환경과학회지
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• 제21권2호
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• pp.165-179
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• 2012

Indirect $CO_2$ effect due to non-methane volatile organic compound (NMVOC) emissions from solvent and product use and fugitive NMVOC emissions from fuels in the Republic of Korea and 13 Annex I countries under United Nations Framework on Climate Change were estimated and the proportions of them to total greenhouse gas (GHG) emissions ranged from 0.092% to 0.45% in 2006. Indirect greenhouse effect ($CO_2$, $CH_4$, and $O_3$) were estimated at 13 photochemical assessment monitoring sites in the Republic of Korea using concentrations of 8 NMVOCs of which indirect global warming potential (GWP) were available. The contribution of toluene to mixing ratio was highest at 11 sites and however, the contribution of toluene to indirect greenhouse effect was highest at nine sites. In contrast to toluene, the contributions of ethane, butane, and ethylene were enhanced. The indirect greenhouse effects of ethane and propane, of which ozone formation potentials are the lowest and the third lowest respectively among targeted 10 NMVOCs, ranked first and fourth highest respectively. Acetaldehyde has relatively higher maximum incremental reactivity and is classified as probable human carcinogen however, its indirect GWP ranked second lowest.

• 설비공학논문집
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• 제26권11호
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• pp.547-552
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• 2014

As global warming in recent years has raised ever more critical concern, refrigerants with high global warming potentials (GWP) are facing the challenge of being phased out. R410A, with a GWP of 2,088, has been widely used in residential air-conditioning and heat pump systems. A potential substitute for R410A is R32, which has a GWP of 675. The present study presents experimental results of an inverter heat pump system that uses R32 as an alternative refrigerant to R410A. Drop-in tests with R32 indicated that the energy efficiency ratio of the system increased by 5.3% in cooling standard mode, and by 4.2% in heating standard mode at the same capacity; and that the cooling and heating capacity increased by about 12% at the same compressor operating frequency, while the annual performance factor (APF) of the system increased by 5.3%.

• 한국공작기계학회논문집
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• 제10권6호
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• pp.102-108
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• 2001

To prevent green house effect and destruction of an ozone layer, an ozone destruction potential(OBP) must be zero and a refrigerant for low global warming potential(GWP) is needed. HFC-l34a, in which hydrogen is mixed instead of chlorine is a refrigerant used for automobile conditioners and its destruction potential is ecologically zero. However, it is not consid- ered as a perfect substitutive refrigerant as its GWP is high. It is studied refrigerant mixtures in which HFC-l52a and $CF_3 I$ in HFC-l52a with low GWP and zero ODP are mixed by experimentally and concluded as follows: 1) With the variation of speed of compressor outside temperature and flow rate, 7he heat of evaporator and compressor and coefficient of perfor- mance was varied, and influenced the air conditioner. 2) The pressure of evaporator was decreased with increasing the speed of compressor and the pressure of evaporator with the refrigerant HFC-l52a was higher 24% than that of azotrope refrigerant mixed with $CF_3 I$

• 한국환경과학회지
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• 제20권6호
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• pp.755-765
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• 2011

Nitrous oxide ($N_2O$) is one of six greenhouse gases listed up in the Kyoto Protocol, and it effects a strong global warming because of its much greater global warming potential (GWP), by 310 times over a 100-year time horizon, than $CO_2$. Although such $N_2O$ emissions from both natural and anthropogenic sources occur, the latter can be controlled using suitable abatement technologies, depending on them, to reduce $N_2O$ below acceptable or feasible levels. This paper has extensively reviewed the anthropogenic $N_2O$ emission sources and their related compositions, and the state-of-the-art non-catalytic and catalytic technologies of the emissions controls available currently to representative, large $N_2O$ emission sources, such as adipic acid production plants. Challengeable approaches to this source are discussed to promote establishment of advanced $N_2O$ emission control technologies.

• 한국대기환경학회지
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• 제30권4호
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• pp.387-397
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• 2014

This work aims at estimating global warming potentials (GWP) of $CF_3Br$ and HFC-134a among green house gases. It has been reported that they have much higher GWP than $CO_2$ in the atmosphere. $CF_3Br$, halon 1301 which is well known to be a fire extinguisher, as one of the bromine-containing halons has been banned since 2003 due to destruction of ozone. HFCs, a kind of chiller which replaced chlorofluorocarbons (CFCs) are one of greenhouse gases regulated by the Kyoto Protocol. In this study, we produced GWPs of $CF_3Br$ and HFC-134a by calculating a life time and measuring an absorption cross section to obtain a radiative forcing (RF). Their absorption cross sections were measured by using Fourier-transformed infrared spectroscopy (FTS) with a gas cell filled with their certified reference materials at room temperature. As a result, the RFs of $CF_3Br$ and HFC-134a were 0.32 and $0.168Wm^{-2}ppb^{-1}$, respectively and the GWPs were calculated as 7989, 6076, 3903 for $CF_3Br$ and 3855, 1300, 656 for HFC-134a for the time horizon of 20, 100, 500 years, respectively. Overall, uncertainty of the estimated GWPs can be estimated to be about 2.6%. Our results were compared with those proposed by the previous studies (IPCC, 2007; WMO, 1999).

• 한국자동차공학회논문집
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• 제10권3호
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• pp.136-142
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• 2002

HFC-134a is currently used as the refrigerant in automobile air-conditioner, replacing the ozone depleting refrigerant CFC-12. Although HFC-l34a has no ozone depletion potential, it has a relatively high global warming potential, approximately 1300 tins that of CO$_2$ over a 100 year time horizon. Therefore, HFC- l34a does not seem to be a perfect alternative refrigerant due to high GWP. For this reason, non-azeotrope refrigerant mixture have been proposed as a long-term and drop-in alternative to HFC-l34a in the automobile air-conditioning system which has variable operating conditions with changes in RPM and pressure ratio. In this study,OS-l2a of which thermodynamic properties are similar to those of HFC-l34a is selected among the mixed refrigerant. HFC-l34a and OS-l2a are examined experimently by the performance test in the same automobile air-conditioning system.

• 한국토양비료학회지
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• 제43권6호
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• pp.886-891
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• 2010

농경지에서 발생되는 온실가스인 $CO_2$, $CH_4$ 그리고 $N_2O$의 배출량을 토성별 지구온난화잠재력으로 평가하기 위하여 수원시에 위치한 국립농업과학원 기후변화생태과 시험포장에서 온실가스 배출시험을 수행하였다. 고추밭에서 온실가스배출 시험은 2005년에 노지재배로 재배하였다. 시비는 화학비료와 돈분퇴비를 시용하였으며, 식양토와 사양토에서 온실가스배출에 영향을 주는 토양수분과 토양온도 등 관련 요인별로 온실가스배출량을 측정하였다. 이와 같이 고추밭에서 $CO_2$, $CH_4$, $N_2O$의 배출량을 확인하고, 지구온난화잠재력으로 환산한 온실가스의 양을 파악하여 온실가스 관리에 필요한 기초 자료로 활용하고자 하였다. 시험한 결과는 다음과 같다. (1) 토성에 따른 $CO_2$배출량은 식양토는 12.9 tonne $CO_2\;ha^{-1}$, 사양토는 7.6 tonne $CO_2\;ha^{-1}$로 나타났다. $N_2O$ 배출량은 식양토 35.7 kg $N_2O\;ha^{-1}$, 사양토 9.2 kg $N_2O\;ha^{-1}$로 나타났으며, $CH_4$ 배출량은 식양토에서 0.054 kg $CH_4\;ha^{-1}$, 사양토 0.013 kg $CH_4\;ha^{-1}$였다. (2) $CO_2$, $CH_4$, $N_2O$의 총 배출량을 지구온난화잠재력 (GWP-Global Warming Potential)으로 환산한 결과, 식양토에서 24.0 tonne $CO_2$-eq $ha^{-1}$, 사양토에서는 10.5 tonne $CO_2$-eq. $ha^{-1}$로 식양토에서 많은 온실가스 배출량을 보였다.

• 대한환경공학회지
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• 제37권7호
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• pp.432-440
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• 2015

유기물의 열분해로 생성되는 바이오차는 토양 탄소 저장량을 증가시킴으로써 기후변화를 완화할 수 있는 전략으로 소개되고 있다. 또한 바이오차는 토양의 흡착능을 증대시켜 중금속으로 오염된 토양을 정화할 수 있다고 보고된다. 본 연구는 두 종류 바이오차의 토양 중금속 제거 효과와 함께 기후변화 완화효과를 동시에 알아보기 위해 수행되었다. 두 종류의 바이오차는 가시박 및 차 찌꺼기 바이오매스를 열분해 하여 준비했다. 납으로 오염된 농경지 토양은 바이오차 및 바이오매스와 혼합되어 60일 동안 배양하였다. $CO_2$, $CH_4$, $N_2O$는 배양 기간 동안 주기적으로 측정되었고 토양 분석은 배양 종료 후 아세트산을 이용한 납 추출량을 비롯한 생화학적 요소에 대해 수행하였다. 그 결과, 배양 후 납의 양은 BC_Ch에서 71% 만큼 감소했다. 배양 중 $CO_2$와 $N_2O$ 발생은 BC_Ch, TW_Ch에서 각각 BC_Bm, TW_Bm 대비 약 24%, 34% 감소하였다. $CH_4$ 발생은 바이오차 처리에 의한 유의한 차이를 나타내지 않았다. GWP 계산 과정에서 온실가스($CO_2$, $CH_4$, $N_2O$), 토양에 처리한 가시박 및 차 찌꺼기 바이오매스와 바이오차, 토양 내 총 탄소량을 고려하였으며, 바이오차 투입으로 토양 내 납의 농도가 감소한 BC_Ch를 제외한 나머지 처리구와 대조구에 제올라이트를 투입하였다고 가정하여 GWP 계산을 수행하였다. BC_Ch가 GWP 측면에서 가장 유리한 것을 보였는데, 이는 가시박 바이오차가 높은 납 흡착과 토양 내 탄소 격리 효과를 나타냈기 때문으로 사료된다. 결론적으로, 가시박으로부터 생성한 바이오차를 투입하는 것이 토양 오염 저감과 기후변화 완화 효과를 동시에 기대할 수 있는 전략임을 시사한다.