• Title/Summary/Keyword: Reducing gases

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Improvement of DeNOx efficiency of SNCR Process with Chemical Additives in Urea Soution (환원제로 우레아를 사용하는 SNCR 공정에서 첨가제 적용에 따른 탈질효율 향상 연구)

  • Yoo, Kyung Seun;Park, Sung Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.10
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    • pp.663-668
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    • 2017
  • Dye waste water generated in the dye industry is categorized as hazardous waste water that requires appropriate treatment. The pilot scale experimental trials were carried out using dye waste water as an effective additive for the selective non-catalytic reduction (SNCR) of NOx in combustion flue gases. The additives were waste liquor obtained from the dye industry and several purification steps were taken to make a standardized reagents. The dye waste water was shown to possess valuable SNCR qualities (at least 87% NOx reduction efficiency) considering its availability as a waste product, which has to be strictly treated, and have little effects on CO removal. The results indicated that the NO removal efficiency increased first and then decreased with increasing temperature within $750-1150^{\circ}C$. The maximum NO reduction efficiency was approximately 87% at the optimal reaction temperature. A more than 10% increase in NO reduction was achieved in the presence of 1000 ppm Na-additives (dye waste water) compared to that without additives. The Na-based additives have also a significant promoting effect on $N_2O$ reduction and within the SNCR temperature window.

The Economic Effects of the Expanding Manufacture and Utilization of Solid Refuse Fuel (SRF) Facilities in Korea : An Input-output Analysis (SRF 제조·활용 시설 확대의 경제적 파급효과 분석)

  • Cho, Yongcheol;Park, Soyeon;Yoo, Seunghoon
    • Journal of Energy Engineering
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    • v.25 no.3
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    • pp.95-103
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    • 2016
  • The government is trying to expanding the manufacture and utilization of solid refuse fuel (SRF) facilities in order to mitigate greenhouse gases reducing and eco-friendly waste-to-energy recovery. In this regard, this study attempts to look into the economic effects of expanding the manufacture and utilization of SRF facilities by applying an inter-industry analysis using a 2014 input-output table. Specifically, by applying the demand-driven model presents the results for the production-inducing effect, value-added creation effect, and employment-inducing effect. In particular, this study attempted to redefine for the SRF. In addition, it was accessed by exogenous around the manufacture and utilization of SRF sector. The results show that production-inducing effect and value-added creation effect of expanding the manufacture and utilization of SRF facilities for the investment of 1.0 won are estimated to be 1.9993 and 0.6747, respectively. The employment-inducing effect of one billion of investment in the expanding the manufacture and utilization of SRF facilities is computed to be 11.1982 persons. This information can be utilized in predicting the economic effects of the manufacture and utilization of SRF.

Effect of Ultra-thin Catalyst Deposited upon $In_2O_3$ Thin Film on CO Sensitivity ($In_2O_3$ 박막위에 증착된 초박막 촉매가 CO의 검출 감도에 미치는 영향)

  • Lee, Hye-Jung;Song, Jae-Hoon;Kwon, Soon-Nam;Kim, Tae-Song;Kim, Kwang-Ju;Jung, Hyung-Jin;Choi, Won-Kook
    • Journal of Sensor Science and Technology
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    • v.9 no.6
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    • pp.430-439
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    • 2000
  • $In_2O_3$-based thin film sensor with 500-600 nm thick was fabricated for the detection of CO gas by rf magnetron sputtering. In order to improve both sensitivity to CO gas and selectivity to hydrogen gas containing -CH, ultra-thin transition metal Co catalyst was sputtered over $In_2O_3$ thin film and annealed at $500^{\circ}C$. Sensitivity to CO was maximum at the thickness of Co 2.1 nm and $300^{\circ}C$, and that to $C_3H_8$ was at the thickness of Co 1.4 nm and $350-400^{\circ}C$. From the x-ray photoelectron spectroscopy (XPS) result, ultra-thin Co was existed into CoO covered with $Co_2O_3$ on $In_2O_3$ particles, and thus p-n junction of $In_2O_3(n-type)$-CoO(p-type) was thought to be formed. In this p-n junction type sensors, sensing mechanism with reducing gases can be explained by the variation of depletion layer thickness formed in the interface.

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Analysis of Patent Trends on the CCUS Technologies (특허 정보 분석을 통한 CCUS 연구개발 동향 분석)

  • Kim, Jung-min;Kim, Seong-Yong;Bae, Junhee;Shinn, Young-Jae;Ahn, Eunyoung;Lee, Jae-Wook
    • Economic and Environmental Geology
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    • v.53 no.4
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    • pp.491-504
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    • 2020
  • Given the continued climate change and global warming, various technologies for greenhouse gas reduction were discussed worldwide as all 195 countries participated in the Paris Agreement on the reduction of greenhouse gases. The agreement was adopted at the 21st Conference of Parties to the UNFCCC (COP21), which was held in Paris, France, in December 2015, and it revealed that reducing CO2 is the most efficient method of greenhouse gas reduction. Accordingly, carbon capture/utilization/storage (CCUS) technology has been noted as a means of making practical contributions to CO2 reduction, and research and development (R&D) activities in many countries are active in the field of CCUS technology. Therefore, this study aims to provide a basis for CCUS R&D and strategic support measures by analyzing patent trends in technologies related to CCUS. The patent analysis collected a total of 10,137 patents in the United States, Korea, Japan, Europe, and China; the number of patents in the United States was the highest according to patent analysis by country. According to an analysis by technology, capture-related technology was high at 60%, but given the recent increase in technology related to utilization, technology demonstration, R&D, and policy support should be continued.

Cold Plasma Treatment Application to Improve Microbiological Safety of Infant Milk Powder and Onion Powder (콜드 플라즈마 처리를 이용한 분유와 양파분말 살균)

  • Oh, Yeong Ji;Lee, Hanna;Kim, Jung Eun;Lee, Seok Hoon;Cho, Hyung Yong;Min, Sea Cheol
    • Korean Journal of Food Science and Technology
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    • v.47 no.4
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    • pp.486-491
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    • 2015
  • The potential of applying cold plasma (CP) treatments to improve microbiological safety of powdered products has been investigated using infant milk powder (IMP) and onion powder (OP). Among the different kinds of CP-forming gases, He-$O_2$ (99.8:0.2) gas mixture and He gas were most effective in reducing the number of Cronobacter sakazakii in IMP and Bacillus cereus spores in OP, respectively. C. sakazakii counts in IMP decreased by $0.9{\pm}0.1{\log}\;CFU/g$ after CP treatment, and the extent of C. sakazakii inhibition increased in a time-dependent manner. CP treatment at 900 W for 20 min reduced the number of B. cereus spores by ~0.4 log spores/g. Treatments that integrated CP with microwave (MW-CP treatment) as well as those that integrated CP with heat and microwave (H-MW-CP treatment) resulted in a 90% reduction in the number of spores in OP. Thus, CP treatments demonstrated potential for decontaminating foodborne pathogens from powdered products, in combination with heat for improved effect.

High-Value Materials from Microalgae (미세조류 유래 고부가 유용물질)

  • 오희목;최애란;민태익
    • Microbiology and Biotechnology Letters
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    • v.31 no.2
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    • pp.95-102
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    • 2003
  • Microalgae are a diverse group of photosynthetic organisms and abundant in every ecosystem in the biosphere. They are common in aqueous environments including marine, brackish and fresh waters and in some habitats that lack eukaryotic life such as some hot springs and highly alkaline lakes. Microalgal biotechnology that is focused on the microalgae-based production of a variety of useful materials such as pharmaceutical comfounds, health foods, natural pigments, and biofuels is considered as an important discipline with the development of biotechnology. In addition, the mass cultivation of microalgae can also contribute to improving the environmental quality by reducing the concentration of $CO_2$ which is one of major gases lead to global warming. Consequently, it seems that the microalgae can be used as an efficient, renewable, environmentally friendly source of high-value biomaterials such as chemicals, pigments, energy, etc. and the microalgal biotechnology will most likely represent a larger portion of modern biotechnology.

Predicting the success of CDM Registration for Hydropower Projects using Logistic Regression and CART (로그 회귀분석 및 CART를 활용한 수력사업의 CDM 승인여부 예측 모델에 관한 연구)

  • Park, Jong-Ho;Koo, Bonsang
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.2
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    • pp.65-76
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    • 2015
  • The Clean Development Mechanism (CDM) is the multi-lateral 'cap and trade' system endorsed by the Kyoto Protocol. CDM allows developed (Annex I) countries to buy CER credits from New and Renewable (NE) projects of non-Annex countries, to meet their carbon reduction requirements. This in effect subsidizes and promotes NE projects in developing countries, ultimately reducing global greenhouse gases (GHG). To be registered as a CDM project, the project must prove 'additionality,' which depends on numerous factors including the adopted technology, baseline methodology, emission reductions, and the project's internal rate of return. This makes it difficult to determine ex ante a project's acceptance as a CDM approved project, and entails sunk costs and even project cancellation to its project stakeholders. Focusing on hydro power projects and employing UNFCCC public data, this research developed a prediction model using logistic regression and CART to determine the likelihood of approval as a CDM project. The AUC for the logistic regression and CART model was 0.7674 and 0.7231 respectively, which proves the model's prediction accuracy. More importantly, results indicate that the emission reduction amount, MW per hour, investment/Emission as crucial variables, whereas the baseline methodology and technology types were insignificant. This demonstrates that at least for hydro power projects, the specific technology is not as important as the amount of emission reductions and relatively small scale projects and investment to carbon reduction ratios.

Effect of different types of biochar on the growth of Chinese cabbage (Brassica chinensis)

  • Lee, Jae-Han;Seong, Chang-Jun;Kang, Seong-Soo;Lee, Ho-Cheol;Kim, Soo-Hun;Lim, Ji-Sun;Kim, Jae-Hong;Yoo, Joun-Hyuk;Park, Jung-Hyun;Oh, Taek-Keun
    • Korean Journal of Agricultural Science
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    • v.45 no.2
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    • pp.197-203
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    • 2018
  • Biochar is the carbon solid produced through the pyrolysis of a biomass from organic sources such as agricultural waste, animal manure, and sludge under limited or anaerobic conditions. Biochar has the effect of reducing greenhouse gases through the carbon sequestration method; additionally, biochar is known to function as a soil amendment. This experiment was conducted to evaluate the application of biochar on the growth characteristics of Chinese cabbage at Chungnam National University in Daejeon, Korea. The Chinese cabbage was grown for 50 days in a glasshouse in pots. A pruning branch was used to produce the bead and pellet forms of biochar through pyrolysis. The biochar was added to the soil at 0, 2, and 5% by weight. The Chinese cabbage with the 2% treatment of the bead form of biochar had the highest fresh weight ($149.43{\pm}15.92g\;plant^{-1}$) which was increased by 10% compared to the control ($136.91{\pm}31.46g\;plant^{-1}$). Moreover, for the 5% treatment of the bead form of biochar ($60.91{\pm}9.82g\;plant^{-1}$), the growth decreased by 57% compared to the control. As the content of the bead form of biochar increased, the shoot dry weight, leaf number, leaf length and lead width that appeared decreased. An increase in the total organic matter, Avail. $P_2O_5$, Ex. cation and EC was observed when the biochar content was increased. Our results support the application of 2% biochar in the bead form for increased growth of Chinese cabbage.

New Smoke Risk Assessment on Wood Treated with Silicone Compound (실리콘 화합물로 처리된 목재의 새로운 연기위험성 평가)

  • Chung, Yeong-Jin;Jin, Eui
    • Fire Science and Engineering
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    • v.33 no.4
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    • pp.16-27
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    • 2019
  • A burning test was conducted on the smoke and combustion gases generated from cypress wood treated with sodium silicate, 3-aminopropyltrimethoxysilane sol, 3-(2-aminoethylamino)propylmethyldimethoxysilane sol, and 3-(2-aminoethylamino) propyltrimethoxysilane sol. The silicone compound sol was applied to each of the cypress wood specimens three times with a brush. The smoke and combustion generation gas were analyzed using a cone calorimeter (ISO 5660-1) and the smoke was also evaluated by applying new smoke risk assessment method. The smoke performance index (SPI) of the cypress treated with silicone compound increased 1.66 to 8.42 times and the smoke growth index (SGI) was 11.8 to 88.2%, respectively. The smoke intensity (SI) is expected to be 1.0~50.5% lower than that of the base specimens, resulting in lower smoke and fire hazards. The third maximum carbon monoxide (COpeak) concentration of the specimens treated with silicone compounds was 22.5~33.3% lower than that of the base specimens. On the other hand, it produced potentially fatal toxicity that was 1.48~1.72 times higher than the US Occupational Safety and Health Administration (OSHA) acceptance standard (PEL). Cypress wood itself produced a high carbon monoxide concentration, but the silicon compound played a role in reducing this level.

Eligibility Analysis of Land on a Reforestation CDM Project in Goseong District, South Korea (청정개발체제하 재 조림 사업의 토지적격성에 대한 사례 분석 -고성군 재조림 사업을 중심으로-)

  • Guishan, Cui;Kwon, Tae-Hyub;Lee, Woo-Kyun;Kwak, Hanbin;Nam, Kijun;Song, Yongho;Hangnan, Yu
    • Journal of Korean Society of Forest Science
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    • v.102 no.2
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    • pp.216-222
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    • 2013
  • For reducing greenhouse gases, many countries carried out a series of activities not only at home but abroad. Particularly, after the release of the Kyoto Protocol, either nation or companies' participation was intensified, due to endow to responsibility of emission limits. This study focused on reforestation CDM work in Goseong Gun based on clean development system. Obstacle factors of land eligibility could be distinguished to three periods: before December 31th 1989, present and future. The obstacle before December 31th 1989 was that land cover of study area hardly illustrated by Landsat image, due to the low resolution, which were confirmed by a document of Grassland Composition Permission instead. The problem of current land eligibility is that the area of trees presence are difficult to be determined as forest or not. The boundary of forest in strata was identified, using 3-Dimensional Cartography Machine and aerial photograph. Land eligibility would still have obstacle whether the study area with trees presence has potentiality to be forest in the future at situation in absence of reforestation project. This was resolved by prediction of tree growth using stem analysis during execution of the project at study area.