• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.327-337
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• 2017

A continuous low temperature ($510^{\circ}C{\sim}530^{\circ}C$) pyrolysis experiment in a pilot-scale of 85.3 kg/hr was carried out by the mixed feedstock of half dried digested sewage sludge and waste plastics. As a result, the amount of pyrolysis gas generated was maximum 68.3% of input dry mass and scored $40.9MJ/Nm^3$ of lower heating value (LHV), and the percentage of air inflow caused by continuous pyrolysis was 19.6%. The oil was produced 4.2% of the input dry mass, and the LHV was 32.5 MJ/kg. The sulfur and chlorine contents, which could cause corrosion of the facility, were found to be 0.2% or more respectively. The carbide generated was 27.5% of the input dry mass which shows LHV of 10.2 MJ/kg, and did not fall under designated waste from the elution test. The concentration of carbon monoxide, sulfur oxides and hydrogen cyanide of emitted flu gas from pyrolysis gas combustion was especially high, and dioxin (PCDDs/DFs) was within the legal standards as $0.034ng-TEQ/Sm^3$. Among the 47 water pollutant contents of waste water generated from dry flue gas condensation, several contents such as total nitrogen, n-H extract and cyanide showed high concentration. Therefore, the merge treatment in the sewage treatment plants after pre-treatment could be considered.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.290-293
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• 2001

In this study, media optimization by statistically designed experiments stimulated an increase in cell growth of Bacillus sp. during batch cultivation. Plackett-Surman design method selected 3 components among 7 components of production medium. Box-Behnken design method calculated the optimum concentration of selected components by Plackett-Surman design. In the optimized medium, viable cell number increased 2 times. Addition of antifoam effected the cell growth depending on the type of antifoam Vegetable oil, are a carbon source and an antifoam. increased cell growth and controlled foaming

• Journal of Korean Society of Environmental Engineers
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• v.27 no.12
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• pp.1263-1269
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• 2005

Horseradish peroxidase, had the phenol degradation rate of 95% in aqueous phase, was covalently immobilized on the surface of reticulated vitreous carbon(RVC) and the degradation of phenol was performed with in situ generated $H_2O_2$-immobilized HRP complex in an electrochemical reactor. The incorporation of carboxylic group on the RVC surface was confirmed by FT/IR spectrometry and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride(EDC) was used for peptide bonds between the carboxylic groups on the RVC surface and amine groups from HRP. The optimal conditions of in situ $H_2O_2$ generation such as concentration($10{\sim}200$ mM) and pH($5.0{\sim}8.0$) of electrolyte, supply of $O_2(10{\sim}50$ mL/min) and applied voltage($-0.2{\sim}-0.8$ volt, vs. Ag/AgCl) from potentiostat/galvanostat were determined by concentration of hydrogen peroxide and current efficiency. It was observed that the RVC immobilized HRP was stable maintaining 89% of the initial activity during 4 weeks. The phenol degradation rate of 86% was attained under the optimal condition of in situ $H_2O_2$ generation.

• Journal of the Korean Institute of Gas
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• v.20 no.6
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• pp.16-22
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• 2016

Coating pipe(PLP) has been generally used in buried site for protecting the corrosion. To prevent the damage by occurring the defect, other construction or execution works, an anti-oxidation environment was forcibly made by using protective potential. Coating and protective potential are applied simultaneously, but corrosion rate or defects are not easy to observe because soil composition has many uncertainty. Also, defect of coating pipe can not be directly observed. A corrosion coupon can easily measure a corrosion rate directly. The corrosion rate was measured with 6 scenarios using corrosion coupon during about 1 year(6 scenarios are based on soil type and protective potential or not in this research. Resultingly, the corrosion coupon has not occurred in the case of protected by potential current, but corrosion has occurred in a non-protected site. The corrosion rate was measured at least in the clay, and the propensity of corrosion rate was similar in other soil(sand and loams). The local corrosion has occurred in the clay because of high water content. On the other hand, general corrosion was occurred in sand and loams. Commonly, sand is not to corrosive soil. Although, corrosion occurred in sand can be estimated by chemical component and valid with chemical analysis report.

• Applied Chemistry for Engineering
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• v.26 no.2
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• pp.224-228
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• 2015

The carbon precursor pitch from pyrolyzed fuel oil (PFO), by-product of Naphta cracking process (NCC), was prepared through heat and UV irradiation treatments with various concentrations of $AlCl_3$, which is a new pitch preparation method. The reformed pitches were characterized by measuring their elemental composition, chemical structure of components, molecular weight distribution, and softening point. The oxygen contents of reformed pitch increased as increasing $AlCl_3$ amounts on the other hand, the carbon and hydrogen contents were not nearly changed. UV irradiated reformed pitches were composed of more aromatic carbon compounds than that of using only heat-treatment without any UV irradiation. The addition of $AlCl_3$ catalyst was ineffective on the aromaticity of reformed pitches. The softening point of prepared pitches was in the range of $103.3{\sim}168.9^{\circ}C$. Also the yield of prepared pitch increased from 48% to 80% when 5 wt% of $AlCl_3$ was added during the heat and UV irradiation reforming. It is expected that the UV irradiation reforming method can be practical and helpful to produce high yields of pitches with diverse properties.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.3
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• pp.110-116
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• 2016

Biogas yields point of view, the possibility of reusing excess sludge treated by thermal pretreatment for the purpose of improving the efficiency of the anaerobic digestion process has been investigated in recent year. Thermal pretreatment technology was considered as a pretreatment technique to improve excess sludge properties because of the solubilization of particulate organics. As a view point of sludge reduction and recycle, however, many researchers focused on the ability of particulate hydrolysis and COD solubilization under a high temperature, and few reports have addressed on the physical/chemical characteristics changing. This research was performed to evaluate the effects of a various temperature and chemical additives on carbon formation and fractionation in treated slurry from thermal pretreatment. Based on the results, it was revealed that oxidants injection and temperature changing have significantly caused the change of carbon fractions in slurry from thermal pretreament. Especially, it was considered that the efficiencies of particle hydrolysis increased with the increase of the reaction temperature. Low molecular weight(Mw < 350 g/mol) organic carbon formation increased with the increase of oxidants injection. It was expected that results of this research will provide an overview of the characteristics of thermal pretreatement for excess sludge reduction and recycle.

• Food Science and Preservation
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• v.16 no.1
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• pp.75-81
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• 2009

Benzo(a)pyrene[B(a)P] levels were determined in processed oils and by-products of corn oil, and removal protocol was formulated. The cause of high level B(a)P contents in corn oil was established. Corn germ had a B(a)P level more than 80% that of whole corn. B(a)P content in final deodorized corn oil was $2.15{\mu}g/kg$, after the usual refining process. B(a)P contents less than $2.0{\mu}g/kg$ could not be attained by routine refining process. However, deodorized corn oil, with B(a)P level of $0.09{\mu}g/kg$, could be prepared by treatment of oil with approximately 2% (w/w) mixed granules(acidic clay:active carbon= 90:10[w/w]). The optimal amount of active carbon was 10% (w/w) that of acidic clay;higher levels of active carbon was not required. The optimal particle size of active carbon was $50{\sim}100$ mesh, removal of B(a)P from bleached corn oil was efficient at this mesh size.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.516-516
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• 2017

기후변화로 인하여, 홍수, 사막화, 엘니뇨 등의 자연재해가 이전보다 더 발생하고 있다. 기후변화 적응은 전 세계적으로 기후변화 대응보다 중요해지고 있다. 기후변화 적응을 위한 이슈 중 하나가 물 순환이다. 각 국가에서는 물 순환을 활성화하기 위한 기술을 개발하고 있다. 특히, 저영향개발(LID, Low Impact Development)이라는 물을 확보하기 위한 정책이 각 국가별로 추진되고 있으며, 이에 따른 기술이 개발되고 있다. 국내에서도 2001년에 국토해양부는 수자원장기종합계획을 발표하고, 환경부에서는 2013년에 LID기술요소 가이드라인과 환경영향평가 시 적용 가능한 저영향개발 매뉴얼을 개발하는 등 LID기술을 개발하고 적용하기 위한 정책을 펼치고 있다. 이러한 LID기술 중 하나가 빗물 집수시스템이며, 이 빗물집수시스템은 주거지역에서 빗물을 배수하고, 집수하여 빗물을 이용하기 위해 적용되고 있다. 현재 적용되고 있는 빗물 집수시스템은 측구 집수시스템과 원형 집수시스템이 있으며, 최근에는 수로형 집수시스템이 적용되는 지역도 있다. 본 연구에서는 전과정 평가(LCA, Life Cycle Assessment)를 이용하여 빗물 집수시스템의 환경성을 평가하고자 한다. 현재, 국내에서는 녹색건축물인증, 탄소성적 표지인증, 환경성적 표지인증 등 LCA를 이용하여 환경성을 평가하고 있다. 특히, 본 연구에서는 기후변화 측면에서 LCA를 적용하여 이산화탄소배출량을 평가하고자 하였다. 본 연구의 범위는 빗물집수시스템 30m로 가정하였으며, 측구 집수시스템, 원형 집수시스템 및 수로형 집수시스템의 건설, 운영 및 유지관리, 해체 및 폐기단계의 전 과정이다. 각 빗물 집수시스템에 대해 각 단계별로 이산화탄소 배출량을 산정한 결과, 수로형 집수시스템은 $2.82\;ton\;CO_2\;eq./set$이며, 원형 집수시스템은 $27.65\;ton\;CO_2\;eq./set$, 측구 집수시스템은 $21.54\;ton\;CO_2\;eq./set$이 배출되었다. 이산화탄소배출량 측면에서는 수로형 집수시스템이 나머지 두집수시스템보다 87~90%가 저감되는 것으로 나타났다. 본 연구는 저영향개발에 대응하는 동시에 기후변화를 대응한다는 측면에서 빗물 집수시스템 정책에 활용되고, 설계시에도 반영될 수 있을 것으로 사료된다. 추가적으로 이산화탄소뿐 만 아니라, 다른 환경성을 평가하는 연구가 진행될 필요가 있다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.81-88
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• 2005

The fly ash has been widely used in the latest to complement the performance and economical efficiency of the concrete which uses only a normal portland cement, the pulp ash gained through the incineration of paper sludge is possible to be used as the material of concrete because it contains the properties similar to the previous fly ash in ingredients and physical characteristics. Therefore, this research has tested physical characteristics by replacing 20% of fly ash used with the paper ash to solve the problem which lowers the early strength caused when the fly ash was used. As a result, it showed that the fluidity becomes lower and the compressive strength becomes increased by using paper ash. In addition, after mixing the paper ash with the fly ash, it showed that time and heating amount of the 2nd peak of the minor heat of hydration affecting the revelation of strength was equivalent to the combination for normal portland cement, and also indicated that the compressive strength for 3 days is superior to the combination of the fly ash. Therefore, if the paper ash having a regular fineness is used, it was effective in improving the early strength of concrete used the fly ash.

• Journal of Korea Port Economic Association
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• v.37 no.1
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• pp.143-157
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• 2021

International organizations such as the World Health Organization, the Organization for Economic Development and Cooperation, and major developed countries recognize the seriousness of air pollution. International organizations such as the International Maritime Organization have also implemented various regulations to reduce air pollution from ships. In line with this international trend, the government has also enacted a special law on improving air quality in port areas, and is making efforts to reduce air pollution caused by ports. The purpose of the Special Act is to implement comprehensive policies to improve air quality in port areas. This study sought to identify the emissions of each source of air pollutants originating from the port and prepare basic data on setting the policy priorities. To this end, the analysis was conducted in six categories: ships, vehicles, loading and unloading equipment, railways, unloading/wild ash dust, road ash dust, and the methodology presented by the European Environment Agency(EEA) and the United States Environmental Protection Agency(EPA). The pollutants subject to analysis were analyzed for carbon monoxide(CO), nitrogen oxides (NOX), sulfur oxides(SOX), total airborne materials(TSP), particulate matter(PM10, PM2.5), and ammonia(NH3). The analysis showed a total of 7,122 tons of emissions. By substance, NOX accounted for the largest portion of 5,084 tons, followed by CO (984 tons), SOX (530 tons), and TSP (335 tons). By source of emissions, ships accounted for the largest portion with 4,107 tons, followed by vehicles with 2,622 tons, showing high emissions. This proved to be the main cause of port air pollution, with 57.6% and 36.8% of total emissions, respectively, suggesting the need for countermeasures against these sources.