국내 광공업 중 자동차 제조업, 금속가공제품 제조업 등 금속가공을 필요로 하는 사업체는 전체 광공업 사업체 163,822개 중 40%를 차지하고 있다. 산업혁명 이래 기계 산업은 빠르게 발전해왔으며 기계 산업이 발달한 현대사회에서 금속 가공 공정은 필수적이다. 이러한 금속 가공 과정에서 금속과 금속사이의 마찰을 줄이기 위한 윤활작용, 마찰로 인한 열팽창 및 변형을 막기 위한 냉각작용, 부식 방지를 위한 방청제 역할을 하는 것이 절삭유이다. 절삭유는 일반적으로 수용성과 비수용성으로 분류되며, 비수용성의 경우 작업 중 및 작업 후 발생하는 오일미스트로 인한 유독성 및 발화 위험 등의 문제가 제기됨에 따라 수용성 절삭유의 사용이 점차 증가하여, 국내 절삭유 사용량의 60% 이상을 수용성 절삭유가 차지하고 있다. 하지만 수용성 절삭유에는 아질산염, 방부제 등 20~30개의 화학물질이 포함되어 있다. 또한, 수용성 절삭유에 함유되어있는 질소계 물질들은 수생태계에 방류되면 부영양화 및 녹조 현상과 같은 문제를 일으킬 수 있으며, 수중에서 산화반응을 하여 아질산성 질소와 질산성 질소로 변화되면서 수계의 용존산소를 감소시켜 오염을 일으킬 수 있어 각별한 처리가 필요한 실정이다. 따라서 본 연구에서는 입상활성탄(Granular activated carbon)을 충진한 충진복극조를 이용해 전기화학적 처리를 통해 수용성 절삭유의 T-N 제거율을 분석하였다. 실험조건은 다음의 Table 1, 실험장치의 구성을 Fig. 1에 간단히 나타내었다.

Rapid industrial development has led to a serious problem of pollution in the industrial sector. With the increasing social need for environmental protection, research on air pollution prevention equipment for reducing pollutants in industrial processes is actively being undertaken. The deterioration of existent, installed facilities, their increased emission rates, and the strengthening of the effluent quality standards make complying with permissible emission standards difficult. In fact, installing new electric precipitators or complementing existent facilities is inevitable. The expansion and complementation of the installed electrical precipitators have led to improvements in dust collection efficiency, shorter working times, and lower costs. Because of its easy installation and simple manufacturing process, the production method with the discharge electrode of an electric precipitator is widely used. The following conclusions were reached by classifying discharge electrodes into four types based on the production method and mutually comparing them by their dust collection efficiency. None of the four types used in this study were damaged by impact. However, we were able to confirm some strain from the compression sites of both type A and type B. Both type B and type C are expected to have greater dust collection efficiencies than the other models due to their large vibration transmissibility. Moreover, the high vibrational energy is expected to cause rapping damage during its operation. Particularly, in the case of type B, some of the strain was found at the end of the compression site. The coupling schemes of both type C and type D are out of vibration transmissibility. On the other hand, the ability to maintain straightness and solidity of the side is regarded as outstanding and stable. Type D has outstanding on-site workability, considering the presence of locking, structural stability, and work conditions. From these experiments, we determined that type C is the most ideal connection method of discharge electrode, considering its construction period of renovation. Type C is inferior to type D with regard to on-site workability. However, type C has outstanding dedusting transmission with regard to the straightness, solidity maintenance, and vibration of shearing stress.

Multi-Walled Carbon Nanotubes (MWCNTs) were modified with epoxy and aminosilane diethanolamine (DEA), and nanocomposites of poly(butylene adipate-co-terephthalate) (PBAT) and the modified MWCNTs were prepared with the aim of improving the physical properties of biodegradable PBAT. The physical and the thermal properties of the PBAT/MWCNT nanocomposites were investigated using various techniques. Fourier transform infrared spectroscopy measurements revealed that the MWCNTs were efficiently modified with DEA. Scanning electron micrographs of the nanocomposites indicated that the modified MWCNTs were dispersed homogeneously in PBAT. The thermal stability of the nanocomposite decreased with increase in the content of epoxy-MWCNT-DEA due to the poor thermal stabilities of epoxy and amino silane DEA. However, the surface hydrophobicity of the nanocomposite increased. The highest stress (170% of PBAT) was observed when the content of epoxy-MWCNT-DEA in the nanocomposite was 2 wt%.

As industry continues to develop, the contents of various recalcitrant substances that are not removed by conventional wastewater treatment have increased in modern society. The metal working fluids (MWFs) used in the metal working process contain chemical substances, such as mineral oils, anticorrosive agents, extreme-pressure additives, and stabilizers, as well as high concentrations of organics and ammonia-nitrogen. Accordingly, MWFs are required to develop advanced treatments to conserve hydro-ecological resources. This study investigated the removal efficiency of ammonia nitrogen from MWFs according to operating time, applied voltage, and NaCl concentration using a Ti/IrO2 electrode in a batch-type reactor. The experimental results showed that ammonia-nitrogen removal efficiencies without NaCl were 89% and 92% when voltage was adjusted to 15 and 20 V for 60 min and removal efficiency was 90% at 25 V for 40 min. Removal efficiencies of 10 mM NaCl were 4% and 2% greater than those of not adding NaCl at 15 V for 50 min and 20 V for 30 min.

1900년대 초부터 금속 가공 장비의 수명 연장 및 가공물의 품질 향상을 위해 금속 가공 공정에 절삭유가 이용되어 왔다. 금속 가공 특성에 따라 절삭효율 향상을 위해 각종 첨가제를 포함시켜 여러 종류의 절삭유가 제조되고 있으며, 일반적으로 수용성과 비수용성으로 분류된다. 비수용성 절삭유의 경우, 폐유처리과정에서 유독성 물질 발생, 발연･발화 등의 문제로 수용성 절삭유의 사용이 점차 증가해 왔으며, 국내에서 이용되는 절삭유의 60% 이상이 수용성 절삭유이다. 사용된 수용성 절삭유는 비수용성 절삭유와 같이 소각처리 하기에는 비용이 크며, 수계로 유출시 COD 약 30,000~100,000ppm의 고농도 유기성분에 의해 인근 수계를 오염시킬 수 있으므로 각별한 처리가 필요하다. 따라서 본 연구에서는 Ti-IrO2전극을 이용하여 NaCl 첨가, 인가전압 변화를 통해 수용성 절삭유 내 오염물질의 전기화학적 처리에 미치는 영향을 검토하고, 수용성 절삭유의 전기화학적 처리에 대한 기초자료를 제공하고자 한다. 시료는 U사의 W1-1종 수용성 절삭유를 이용하였으며 증류수와 혼합하여 5% 농도의 인공 시료를 제조하였다. 시료의 특성은 Table 1, 실험 조건은 Table 2에 나타내었다.

2012년 현재, 국내 광공업 중 자동차 및 트레일러 제조업, 금속가공제품 제조업 등 금속가공을 필요로 하는 사업체는 전체 광공업 사업체 중 약 40%를 차지하고 있으며, 이와 같은 금속가공 과정에서 필요로 하는 것이 절삭유이다. 그러나 절삭유 내에는 50~80% 정도의 미네랄 오일 외에 amins, carboxylates, chlorine, glycols와 같은 부식방지제, 안정제, 습윤제, 극압 첨가제 등 20여종 이상의 화학성분이 다량 함유되어 있으며, 인체에 지속적으로 노출 시 호흡기 자극, 천식, 폐렴, 피부염, 모낭염 및 피부암 등을 일으키게 된다. 또한 고농도의 유기성분이 함유되어 있으며 유기성분 외에도 금속가공유 내 함유된 암모니아성 질소는 수생태계에 방류되면 부영양화 및 녹조현상과 같은 문제를 일으키며, 수중에서 산화반응을 하여 아질산성 질소와 질산성 질소로 변화되면서 수계의 용존산소를 감소시켜 수계 내 오염을 일으켜 각별한 처리가 필요하다. 따라서 본 연구에서는 수용성 절삭유의 효율적인 처리를 위해 용성전극인 알루미늄과 SUS316전극을 이용하여 전극간격, 전압, NaCl 농도변화를 통해 암모니아성 질소 제거 효율에 미치는 영향을 검토하여, 전극 특성과 각 인자에 따른 제거양상을 비교하였다. 본 연구에서 사용한 시료는 수용성 절삭유 W1-1종을 초순수와 함께 5%(V/V) 희석하여 사용하였으며 성상은 Table 1과 같다. 장치구성은 반응조, 전극, 전원공급장치, 전압안정기(AVR)로 진행하였으며, 장치모식도는 다음 Fig. 1에 나타내었다.

Generally, metal working fluids (MWFs) are used to reduce friction in metalworking processes. In addition to mineral oils, MWFs contain many chemical substances, such as anticorrosive agents, extreme-pressure additives, and stabilizers, as well as high concentrations of organics and ammonia nitrogen. Accordingly, MWFs must be managed to advanced treatment for hydro-ecological conservation. This study investigated the removal efficiency of ammonia nitrogen from MWFs according to operating time, applied voltage, distance between electrodes, and NaCl concentration using aluminum in a batch-type reactor. The experimental results were as follows: First, without NaCl, removal efficiencies of ammonia nitrogen were 69.6%, 37.9%, and 22.7%, when the distance between electrodes was adjusted to 1, 4, and 7 cm, respectively, at 15 V for 60 min. Secondly, without NaCl, removal efficiencies of ammonia nitrogen were 49.5 and 90.9% when the voltage was adjusted to 5 V and 10 V, respectively, for 60 min and 94.6% at 15 V for 40 min. Lastly, with the addition of NaCl 10 mM, the removal efficiency of ammonia nitrogen was 40.3% and 11.5% greater than that of no addition of NaCl at 5 V for 60 min and at 10 V for 30 min.

An electrochemical treatment has great efficiency for the removal of non-biodegradable material and it has high applicability in wastewater treatment due to its short operating time. The purpose of this study using an electrochemical process is to provide fundamental data on the cutting fluid treatment, which has difficulties in the treatment of nonbiodegradable material. The results are as follows. Experimental data in relation to applied voltage and concentration of NaCl are outlined. With no addition of NaCl, and an applied voltage of 5 V, 10 V, or 15 V for 60 mins, the removal rates of CODMn were 29.87%, 55.32%, and 67.27% for each voltage. The removal rates of CODCr were 39.51%, 70.73%, and 85.37%, respectively. The removal rates of CODMn and CODCr increased with increasing applied voltage. These experimental results showed that the removal rate of COD with varying concentrations of NaCl (0 mM, 5 mM, 10 mM) increased increasing NaCl concentration.

This study is to identify the effects of DRE (destruction and removal efficiency) and carbonization of Xylene when using the electron beam energy. The irradiation intensity of electron beam energy was 10 mA, 20 mA and irradiation time was 5.7, 11.4, 22.8, 45.6 sec (Absorbed dose are 41.41, 82.82, 165.64, 331.28, 662.55 kGy). The Xylene was completely removed at 331.28 kGy. Main by-products was carbon particles. Carbon particle formation was increased with irradiation intensity increasing. Most of the by-products of particle were Carbon black and Graphite.

The purpose of this study was to measure the antioxidant activity and bioactivity of black chokeberry (Aronia melanocarpa). The black chokeberry was known to contain many physiologically active substance, such as ascorbic acid, anthocyanin, quercetin. We extracted black chokeberry powder from four solvents such as chloroform:methanol(CM, 2:1, v/v), distilled water (DW), 70% ethanol, 70% methanol. After that, we determined anthocyanin, total phenol, flavonoid content, DPPH radical scavenging activity, ABTS radical scavenging activity, ferric reducing antioxidant power, reducing power and Nitrite scavenging activity of black chokeberry extracts and as results of comparing each extract. respectively. From the above results shows that antioxidant activity and bioactivity of black chokeberry extracts was the highest in 70% methanol (p<0.05). The results suggest that black chokeberry can be used as nutraceutical foods and natural antioxidant.

화석에너지 자원 고갈 및 경제발전에 따른 산업화가 가속화되면서 폐기물의 발생량이 지속적으로 증가하여 폐기물 에너지화 기술에 대한 관심이 급증하고 있다. 공정상에 발생하는 폐기물 중에서 특히, 메탄올의 경우에는 분리가 쉬우며 저장성이 용이하고 연료전지 사용 및 수소에너지로의 변환이 용이하므로 많은 전원장치에서 응용이 가능하다. 공정상에서 비상전원의 경우에는 배터리 또는 연료전지를 이용하게 된다. 이때 PEM 연료전지를 이용할 경우 배터리에 비해 에너지 밀도가 현저히 높기 때문에 장시간 비상전원 공급이 가능하다. 메탄올의 경우에는 다른 폐기물에 비해서 높은 수소 : 탄소 비를 가지며 낮은 끓는점을 가지면서 공정 폐기물에서 쉽게 추출할 수 있으며 저장하는데 별도의 장치가 필요 없고 또한 낮은 온도에서 간단한 조건에서 쉽게 개질이 가능하므로 연료전지 시스템에 적용이 용이하다. 본 연구에서는 공정상 추출한 메탄올을 비상전원장치의 연료로 사용한 PEM 연료전지에 적용이 가능한 메탄올 개질 반응에 대한 연구를 수행하였다. 수소를 생산하는 개질반응에는 열분해 반응, 수증기 개질 반응, 부분 산화 반응 및 수증기 개질 반응 및 부분 산화 반응의 조합으로 이루어진 자열 개질 반응이 존재한다. 4가지의 개질반응에 대한 각각의 실험을 수행하여 비상전원시스템으로의 적합성에 대한 연구를 수행하였다. 비상전원시스템의 경우에는 구조가 간단하고 부가 장치가 적을수록 가공, 제작 및 장치 구동 면에서 유리하고 또한 성공적인 비상 PEM 연료전지 구동을 위한 수소 생산을 위해서는 연료 개질 시스템은 복잡하게 구성되며 연료전지의 구동 온도가 낮을수록 더 많은 과정을 거치게 된다. 비상전원시스템에서 동적 부하 변동에 빠른 응답성을 가지며 동시에 메탄올에 대해서 비교적 안정적인 운전이 가능하며 외부 열원의 사용을 최소화 할 수 있는 개질 반응 연구를 수행하였다. 다양한 개질 반응에 대한 수소 발생률 및 BOP(Balance of Plant)의 비교 검증을 통하여 비상전원시스템에 가장 적합한 개질 반응에 대한 선택을 하였으며 선택된 개질 반응을 이용하여 비상 PEM 연료전지 전원장치 시스템에 적용시켰다. 이는 비상 PEM 연료전지 전원장치 뿐만 아니라 다양한 연료 처리 장치에 적용 가능할 것으로 판단된다.

Volatile Organic Compounds in Urban Atmosphere are contributing largely at significant risks to human health andhave caused serious problems such as ozone formation. This study is to identify the effects of DRE (destruction andremoval efficiency) and carbonization of styrene when using the electron beam energy. The irradiation intensity of electronbeam energy was 1mA, 5mA and irradiation time were 5sec and 10sec. The styrene was completely destroyed at 5mA.Main by-products was aerosol particles. Aerosol particle formation was increased with increasing irradiation intensity.Most of the by-products of particle were carbon.

Results of reviews on bio-gas production and policy trends in the European Union (EU) are as follows. In the EU,Germany leads in bio-gas production with 29 TWh of energy produced through energy crops as of 2013. This could beachieved through renewable energy laws and increases in feed in tariff (FIT) schemes in Germany. In the EU, bio-gashas been verified to play an important role and contribute to greenhouse gas reduction. However, it is necessary to providea measure to improve sustainability criteria and decrease the consumer's share of expenses. If bio-gas is produced usingorganic wastes instead of energy crops, this problem can be solved. If the bio-gas production policies in the EU are appliedin South Korea, bio-gas market will be promoted and greenhouse gas emission can be reduced in the future.

Mechanical Biological Treatment (MBT), widely spread in Europe, is a process combined with mechanical separation and biological treatment. This is an alternative technology that can accomplish WtE (Waste-to-Energy) and landfill diversion. Bio-drying, aimed to produce high quality SRF, focused on removing moisture of waste through generated heat when biodegradable organic material is partially degraded by micro-organism. However, most of SRF production facilities in Korea consist of mechanical treatment. In those, 40% of input waste have been generated as residue disposed of in landfill. As a result of physico-chemical characteristic analysis of residue from target facilities, composition of food wastes, papers and plastics ranged 6.7 ~ 18.3%, 9.1 ~ 17.3%, and 5.8 ~ 12.2%, respectively. The moisture content of residue was about 43%, and low heating value was analyzed a range of 1,300 up to 1,900 kcal/kg. Results showed that combustible material having potential to produce SRF is discarded and the amount of biodegradable material such as food waste is still large. Therefore, we assumed it may cause pollution in terms of landfill gas emission and high concentrated leachate generation. In this study, recent trends of Bio-drying is discussed as the alternative technology to solve problems at SRF production facilities in South Korea.

Nitrogen trifluoride (NF3) and Sulfur hexafluoride (SF6) are usually used as novel etching and cleaning gases in semiconductor industry and electrical equipments. Recently, the many studies about PFCs decomposition have been performed due to high global warming potential (GWP). This study is to identify the effects of the hydrogen on the destruction and removal efficiency (DRE) of NF3 and SF6 when using the electron-beam. The experiment was conducted at a flow rate of 10 LPM with NF3 and SF6 of 1,000 ppm. Absorbed dose (electric current) was 1,028 kGy (5 mA). The DREs of NF3 and SF6 gases increased about 54% and 68% respectively with hydrogen injection. By-products formed by NF3 and SF6 destruction were mainly HF and F2 gases. In addition, the particles were generated during the NF3 and SF6 destruction due to corrosion of reactor and SF6 decomposion, respectively.

This study was conducted to evaluate the contents of antioxidative components from pulpy and seed in wild haw (Crataegus pinnatifida BUNGE). Pulpy and seed of haw were smashed, then measured for color properties, antioxidative components of ascorbic acid, phytic acid, proanthocyanidin, anthocyanin, total carotene, β-carotene, lycopene, chlorophyll a, b and tannin. The a*, b* and C* values of seed were significantly lower than pulpy, but L* and H° values were higher than that of pulpy. Ascorbic acid contents of pulpy and seed were found to be 10.89±1.69 mg/100 g and 1.45±0.16 mg/100 g, respectively. Phytic acid, proanthocyanidin, total carotene and tannin contents of pulpy and seed were 689.17±3.63 mg/g, 597.78±2.93 mg/g; 355.61±19.39 mg/g, 49.12±4.97 mg/g; 8.32±0.42 mg%, 0.80±0.01 mg%; 7.53± 0.09 mg/g, 1.02±0.03 mg/g, respectively. Similarly, β-carotene, lycopene, chlorophyll a and chlorophyll b contents of pulpy also displayed higher values than that of seed. On the contrary, anthocyanin content of seed (4.24±0.33 mg/L) was remarkably higher than pulpy (0.99±0.62 mg/L). The results showed that pulpy could be severed as great natural antioxidant and biohealth functional food.