• Resources Recycling
• /
• v.22 no.3
• /
• pp.91-99
• /
• 2013

Steel industry which has been accomplishes the base of our country economy, automobile and electronic industry are taking charge of the role, whose electroplating is important. Large amount of wastewater and various metal salts, including hazardous materials was generated from the electroplating pre-treatment, plating, washing and post-plating. Currently, the general wastewater follows in the environmental law and neutralization after controlling, sludge where the various metal is mixed reclaims below multiple regulative and trust it is controlling. The sludge which includes the gas price metal reclaims in the field and trust it controls. a reclamation price of land it is insufficient but and the control expense holds plentifully and it loses the gas price metal which is valuable. Consequently, The research regarding to recover a gas price metal actively from this waste water, it is advanced. A new method to recover valuable metals from electroplating wastewater synthesis of metal sulfides using topical methods utilizing iron oxidizing bacteria, reagent of sulfides and solvent extraction using an organic solvent, such as the development of the law to recover these metals and metal sulfides of wastewater using selective recovery have been studied. By using these wastewater treatment method under frequency above 95%, it has been obtained the valuable metal from the wastewater, where the metal ion of Fe, Cu, Zn and Ni complexes was mixed. As we discuss the wastewater, which has been discharged from electroplating process, it is important and will be applied to the resources of metal in the urban mine.

• Journal of the Korean Wood Science and Technology
• /
• v.42 no.3
• /
• pp.318-326
• /
• 2014

This study was conducted to investigate the potential of non-used forest biomass residues as raw materials for making wood pellets with additives such as wood tar and starch and to evaluate fuel characteristics of the pellets. Wood tar, a by-product provided from the carbonization process of wood, could be a suitable additive for wood pellet production due to its higher calorific value and lower hazardous heavy metals, such as cadmium and mercury, compared to woody biomass. When the wood tar (10 wt%) was added, the calorific value was increased from 4,630 kcal/kg (wood pellet without additive) to 4,800 kcal/kg (wood pellet with additive). With the increase of additive amount into wood pellet, the length and individual density of wood pellet increased. In addition, bulk density of the pellets was increased, whereas the fine content was decreased. Consequently the overall productivity of wood pellets was improved by adding 2 w% additives into wood pellets; the percentage of productivity increase was 5.9% and 4.9% for adding starch and wood tar, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.4
• /
• pp.718-725
• /
• 2017

A liquid storage tank is one of the most important structures in industrial complexes dealing with chemicals, and its structural damage due to an earthquake may cause a disastrous event such as the leakage of hazardous materials, fire, and explosion. It is thus essential to assess the seismic fragility of liquid storage tanks and prepare for seismic events in advance. When a liquid storage tank is oscillated by a seismic load, the hydrodynamic pressure caused by the liquid-structure interaction increases the stress and causes structural damage to the tank. Meanwhile, the seismic fragility of the structure can be estimated by considering the various sources of uncertainty and calculating the failure probabilities in a given limiting state. To accurately evaluate the seismic fragility of liquid storage tanks, a sophisticated finite element analysis is required during their reliability analysis. Therefore, in this study, FERUM-ABAQUS, a recently-developed computational platform integrated with commercial finite element and reliability analysis software packages, is introduced to perform the finite element reliability analysis and calculate the failure probability of a liquid storage tank subjected to a seismic load. FERUM-ABAUS allows for automatic data exchange between these two software packages and for the efficient seismic fragility assessment of a structure. Using this computational platform, the seismic fragility curve of a liquid storage tank is successfully obtained.

• Resources Recycling
• /
• v.21 no.1
• /
• pp.17-29
• /
• 2012

potential assessment of converting closed non sanitary landfills into sustainable landfill through the reclamation works(= landfill mining project) of illegal landfill discovered in land development site using Sustainable Landfill Reclamation system(SLR-system) was investigated. The SLR system had treatment capacity of 91.4 $m^3/hr$ (130.61 ton/hr) in condition of 28.0% of water content. Recovery ratio and purity of sorted soil were 98.9% and 99.66%, respectively. Sorted combustibles were 91.8% and 92.0%, respectively. Especially, high heating value (HHV) and low heating value(LHV) of combustibles were 4,282kcal/kg and 3,636 kcal/kg, respectively, in considering the energy content and recovery ratio of combustibles. Therefore, combustibles separated from landfill site have higher value than Fluff RDF standard value(3,500kcal/kg) of MOE. RDF can be produced with combustibles by 84.43%. Averaged size and organic foreign matter content of the sorted soil were less than 035mm and 0.31 %(VN), respectively. In addition, concentration of all contents of hazardous matters containing soils met safety standards. Therefore, it is possible to be recycled as refilling and cover materials to rebuild Sustainable landfills by 98.42%.

• Journal of Life Science
• /
• v.31 no.9
• /
• pp.862-872
• /
• 2021

Recent studies on synthesis of metallic nanomaterials such as silver (Ag), gold (Au), platinum (Pt), cerium (Ce), zinc (Zn), and copper (Cu) nanoparticles (NPs) using plants and microbes are attracted researchers for their wide range of applications in the field of biomedical sciences. The plant contains abundant of bioactive contents such as flavonoids, alkaloids, saponins, steroids tannins and nutritionals components. Similarly, microbes produce bioactive metabolites, proteins and secretes valuable chemicals such as color pigments, antibiotics, and acids. Recently reported, biogenic synthesis of NPs in non-hazardous way and are promising candidates for biomedical applications such as antibacterial, antifungal, anti-cell proliferative and anti-plasmodia activity. All those activities are dose dependent, along with their shape and size also matters on potential of NPs. Microbes and plants are great source of metabolites, those useful in biomedical field, such metabolites or chemicals involved in synthesis of NPs in an ecofriendly way. NPs synthesized using microbes or plant materials are reveals more non-toxic, facile, and cost-effective compare to chemically synthesized NPs. In present review we are focusing on NPs synthesis using biological agents such as microbes (bacteria, fungi and algae) and plant, characterization using different techniques and their antibacterial applications on pathogenic Gram-positive and Gram-negative organisms.

• The Korean Journal of Air & Space Law and Policy
• /
• v.33 no.2
• /
• pp.115-168
• /
• 2018

An amendment to Japanese Civil Aeronautics Act came into effect December 10, 2015. The Act prohibits flying drones over residential areas or areas surrounding an airport without permission from the Minister of Land, Infrastructure and Transportation. Flying drones during night time and during an event is also prohibited. The term "UAV" or "UA" means any aeroplane, rotorcraft, glider or airship which cannot accommodate any person on board and can be remotely or automatically piloted (Excluding those lighter than a certain weight (200 grams). Any person who intends to operate a UAV is required to follow the operational conditions listed below, unless approved by the Minister of Land, Infrastructure, Transport and Tourism; (i) Operation of UAVs in the daytime, (ii) Operation of UAVs within Visual Line of Sight (VLOS), (iii) Maintenance of a certain operating distance between UAVs and persons or properties on the ground/water surface, (iv) Do not operate UAVs over event sites where many people gather, (v) Do not transport hazardous materials such as explosives by UAV, (vi) Do not drop any objects from UAVs. Requirements stated in "Airspace in which Flights are Prohibited" and "Operational Limitations" are not applied to flights for search and rescue operations by public organizations in case of accidents and disasters. This paper analyzes some issues as to regulations of UAVs in Korean Aviation Safety Act by comparing the regulations of UAVs in Japanese Civil Aeronautics Act. This paper, also, offers some implications and suggestions for regulations of UAVs under Korean Aviation Safety Act.

• Journal of the Korean Institute of Gas
• /
• v.22 no.6
• /
• pp.136-143
• /
• 2018

Cellular automata have been applied to simulations in many fields such as astrophysics, social phenomena, fire spread, and evacuation. Using cellular automata, this study develops a model for consequence analysis of the dispersion of hazardous chemicals, which is required for risk assessments of and emergency responses for frequent chemical accidents. Unlike in cases of detailed plant safety design, real-time accident responses require fast and iterative calculations to reduce the uncertainty of the distribution of damage within the affected area. EPA ALOHA and KORA of National Institute of Chemical Safety have been popular choices for these analyses. However, this study proposes an initiative to supplement the model and code continuously and is different in its development of free software, specialized for small and medium enterprises. Compared to the full-scale computational fluid dynamics (CFD), which requires large amounts of computation time, the relative accuracy loss is compromised, and the convenience of the general user is improved. Using Python open-source libraries as well as meteorological information linkage, it is made possible to expand and update the functions continuously. Users can easily obtain the results by simply inputting the layout of the plant and the materials used. Accuracy is verified against full-scale CFD simulations, and it will be distributed as open source software, supporting GPU-accelerated computing for fast computation.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.31 no.1
• /
• pp.1-12
• /
• 2021

Objective: The purpose of this study was to contribute to the prevention of occupational diseases through the development of an automatic analysis program for evaluating workers' exposure to hazardous chemical substances. Methods: The authors selected chemical substances that caused occupational disease in Korea and chemical substances that are frequently used in industrial sites as target substances for a GC-MS automatic analysis program. The target substances are organic compounds which can be measured by a passive sampler. The automatic analysis program was studied using various raw data obtained from GC-MS analysis for the target substances. Results: A total of 48 organic compounds that can be measured with a passive sampler were selected as target substances for the GC-MS automatic analysis program. The selected compounds included substances that caused occupational disease, substances related to C1 and D1 in special health examinations, and substances for which work environment measurements have been frequently conducted. The GC-MS automatic analysis program was developed by combining information mainly on retention time and mass spectrum. The GC-MS automatic analysis program is designed to analyze unknown samples by comparing the mass spectrum and retention time of the samples to those of reference materials. To evaluate the stability of the program, samples at about the 30-50% level of OELs were prepared and analyzed with the GC-MS automatic analysis program, resulting in stable results for all 48 organic compounds. Conclusion: An automatic analysis program for a total of 48 organic compounds was developed using a GC-MS system that can analyze organic compounds. Unknown samples that contain the 48 organic compounds can be automatically analyzed by the developed program. It is anticipated that it can contribute to the prevention of occupational diseases through an GC-MS automatic analysis program that can quickly provide workers with information on exposure to chemical substances.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.3
• /
• pp.651-660
• /
• 2021

This study examined the trend of standards established in the United States and to find points that can be applied to Korean defense standards. The titles of various United States defense standard documents registered on the web were selected for this research. The wordcloud was created after analyzing the frequency of words appearing in the title using text mining. The trend of words appearing in MIL-STD by era was obtained. This study identified words that appear often due to the format of the document itself, words that appear regularly throughout the era, words that are used frequently in the past but are not used much in the present, and words that did not receive attention in the past but appeared recurrently in the present. In addition, the characteristics of each document were derived through the wordcloud produced for various defense documents. In conclusion, Korean defense standards also require a consideration of safe and efficient management, transport, and load design of hazardous materials. Furthermore, the quality of defense standards can be expected to improve if the defense standard document system can be established, focusing on efficient management.

• Journal of Korea Society of Waste Management
• /
• v.35 no.7
• /
• pp.670-682
• /
• 2018

Engineered nanomaterials (ENMs) can be released to humans and the environment through the generation of waste containing engineered nanomaterials (WCNMs) and the use and disposal of nano-products. Nanoparticles can also be introduced intentionally or unintentionally into waste streams. This study examined WCNMs in domestic industries, and target nanomaterials, such as silicon dioxide, titanium oxide, zinc oxide, nano silver, and carbon nanotubes (CNTs), were selected. We tested 48 samples, such as dust, sludge, ash, and by-products from manufacturing facilities and waste treatment facilities. We analyzed leaching and content concentrations for heavy metals and hazardous constituents of the waste. Chemical compositions were also measured by XRD and XRF, and the unique properties of nano-waste were identified by using a particle size distribution analyzer and TEM. The dust and sludge generated from manufacturing facilities and the use of nanomaterials showed higher concentrations of metals such as lead, arsenic, chromium, barium, and zinc. Oiled cloths from facilities using nano silver revealed high concentrations of copper, and the leaching concentrations of copper and lead in fly ash were higher than those in bottom ash. In XRF measurements at the facilities, we detected compounds such as silicon dioxide, sulfur trioxide, calcium oxide, titanium dioxide, and zinc oxide. We found several chemicals such as calcium oxide and silicon dioxide in the bottom ash of waste incinerators.