• Advances in environmental research
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• v.9 no.2
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• pp.135-150
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• 2020

Many industries, such as textiles, chemical refineries, leather, plastics and paper, use different dyes in various process steps. At the same time, these industrial sectors are responsible for discharging contaminants that are harmful and toxic to humans and microorganisms by introducing synthetic dyes into wastewater. Of these dyes, methylene blue dye, which is classified as basic dyes, is accepted as a model dye. For this reason, methylene blue dye was selected in the study and its removal from the water was studied. In this study, two efficient biosorbents were developed from chitosan and sunflower waste, an agro-industrial waste and modified using iron nanoparticles. The biosorption efficiency was evaluated for methylene blue (MB) dye removal from aqueous solution under various parameters such as treating agent, solution pH, biosorbent dosage, contact time, initial dye concentration and temperature. We investigated the kinetic properties of dye removal from water for Chitosan-Sunflower (CS), Chitosan-Sunflower-Nanoiron (CSN). When the wavelength of MB dye was spectrophotometrically scanned, the maximum absorbance was determined as 660 nm. For the core shell biosorbents we obtained, we found that the optimum time for removal of MB from wastewater was 60 min. The pH of the best pH was determined as 5 in the studied pH. The most suitable temperature for the experiment was determined as 30℃. SEM-EDAX, TEM, XRD, and FTIR techniques were used to characterize biosorbents produced and modified in the experimental stage and to monitor the change of biosorbent after dye removal. The interactions of the paint with the surface used for removal were explained by these techniques. It was calculated that 80% of CS and 88% of CSN removed MB in optimum conditions. Also, the absorption of MB dye onto the surface was investigated by Langmiur and Frendlinch isotherms and it was determined from the results that the removal was more compatible with Langmiur isotherm.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.10
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• pp.63-71
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• 2021

Using fossil fuels in existing industrial systems causes a variety of social problems. Recently, many studies have been conducted on bio-refineries, which aim to actively utilize biomass to reduce the use of fossil fuels and solve various social problems. Among them, research using microalgae as a third-generation biomass has attracted considerable attention. Microalgae use inorganic matter to produce organic matter, and cell destruction is necessary to extract useful organic materials from microalgae. The extracted organic materials are currently used in various industrial fields. Numerous cell-destruction methods exist. We have investigated cell disruption by sonication, especially its efficiency. Ultrasound is a sound wave with frequencies above 20 kHz, and destroys cells by sending high energy through a cavitation that occurs, according to the characteristics of the sound wave. The Dunaliella salina microalgae used in this study was cultured in a flat-type photobioreactor. Experiments were performed using a batch low-frequency processing device. Logistic model was applied to analyze the results of cell-destruction experiments using ultrasound. The proper conditions for the most efficient cell destruction were OD 1.4(microalgae concentration)), 54watt(output power) and 200mL(microalgae capacity).

• Journal of the Korean Institute of Gas
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• v.25 no.5
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• pp.52-56
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• 2021

With the development of an eco-friendly environment and the automobile industry, research is being actively conducted to increase thermal efficiency and reduce exhaust gas through complete combustion in internal combustion engine vehicles. In particular, research is underway to increase engine load and output by understanding the volatility and combustion characteristics of gasoline, and research is underway to reduce soot and harmful gases and realize optimal efficiency based on the distillation and combustion characteristics of diesel fuel. . Therefore, in this study, based on the contents of KS M ISO 3045 on the distillation test method for petroleum products according to the Korean industrial standard, distillation experiments were conducted based on gasoline and diesel from 4 refineries marketed and used in Korea. The distillation experiment confirmed the correlation with the distillation temperature according to the amount of distillation, and the distillation characteristics were analyzed by comparing the distilled fuel to confirm the suitability of meeting the test standards.

• Korean Chemical Engineering Research
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• v.57 no.4
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• pp.455-460
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• 2019

Hydrotreating catalysis refers to a various hydrogenation which saturate an unsaturated hydrocarbon, together with removing heteroatoms such as sulfur, nitrogen, oxygen, and trace metals from different petroleum streams in a refinery. Most refineries include at least three hydrotreating units for upgrading naphtha, middle distillates, gas oils, intermediate process streams, and/or residue. Among them, hydrotreating catalysis for residue are the core of the process, because of its complexity. This article reviews recent progress in tackling the issues found in the upgrading residues by hydrotreating, focusing on the chemistry of hydrodemetallization (HDM) and hydrodesulfurization (HDS). We also discuss the composition and functions of hydrotreating catalysts, and we highlight areas for further improvement.

• Fire Science and Engineering
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• v.33 no.2
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• pp.107-113
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• 2019

Recently, due to global warming, the trend shows an increase in number of lightning strikes which increase risk regarding industry infrastructures. Especially in case where the lightning strikes infrastructures including refinery, petorchemical plant facilities or storage tanks, it can cause power failures, electrical machine malfunction and damage which can lead to fire explosion and multiple calamities. Therefore, detailed case studies must be conducted through a systematic research regarding lightning strike accidents in order to understand its mechanism and devise preventive measures. This paper aims to study cases of explosion regarding waste water storage tanks in refineries and petrochemical plants in order to analyze its root cause and provide preventive measures for avoiding lightning related incidents.

• Membrane Journal
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• v.32 no.2
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• pp.83-90
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• 2022

Wastewater from refineries and petroleum plant lead to severe environmental pollution. There are various existing processes applied for oily water treatment, but membrane-based technology is one of the most efficient methods. Polymeric membranes prepared from organic materials for the separation of oil in water often face chronic problem of membrane fouling. Inorganic membranes are considered to be more efficient due to longer lifetime than organic membranes. Zeolite membranes have better chemical stability and long-term recyclability. The presence of hydrophilicity enhances the water flux of membrane. Ceramic membranes prepared from zeolites are another efficient class of inorganic membranes applied for oil water separation. This review is focused on oily wastewater separation based on zeolite membrane which classified into two categories, i) neat zeolite and ii) zeolite composites with other materials.

• Safety and Health at Work
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• v.14 no.4
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• pp.358-367
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• 2023

Background: This study aimed to develop and assess the psychometric features of the Physical Activity at Workplace Questionnaire (PAWPQ) based on the Social Cognitive Theory (SCT) to evaluate employees' physical activity (PA) behaviors at the workplace. Methods: This psychometric cross-sectional study was conducted on 455 employees working in one of the gas refineries in Iran. The participants were selected using the proportional stratified sampling method in 2019. The data collection tools were a demographic information questionnaire, the short form of the International Physical Activity Questionnaire (IPAQ), and a questionnaire developed based on the SCT, whose psychometric features were confirmed in terms of validity and reliability. Data were analyzed using SPSS₂₂ and AMOS₂₀ software. Results: The first version of PAWPQ-SCT had 74 items. After evaluating content and face validity, nine items were removed. The results of the content validity index (0.98), content validity ratio (0.86), and impact score (3.62) were acceptable for the whole instrument. In exploratory factor analysis, after removing seven items-58-item final version of the scale-six factors could explain 73.54% of the total variance. The results of structural equation modeling showed the acceptable fit of the model into the data (RMSEA = 0.052, CFI = 0.917, NFI = 0.878, TLI = 0.905, IFI = 0.917, CMIN/DF = 2.818). Cronbach's alpha coefficient and Intraclass Correlation were 0.90 and 0.86, respectively. Conclusion: This study confirmed that the psychometric features of the 58-item final version of PAWPQSCT constructs were acceptable in a sample of Iranian employees. This questionnaire can be used as a valid and reliable tool to evaluate Iranian employees' PA behaviors and develop effective educational interventions for workers and managers.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.3
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• pp.147-155
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• 2010

This study was conducted to investigate the benzene exposure levels in coal chemical and petrochemical refining industries during BTX turnaround (TA) processes where benzene was being produced. Three companies producing benzene were selected, one coal chemical and two petrochemical industries. TA processes were classified into three stages: shut down, maintenance, and start up. Data was analyzed by classifying the refining method into 2 groups (Petrochemistry, Coal chemistry) for 823 workers. Comparing the data from petrochemical industries with data from a coal chemical refining industry, while benzene concentration levels of long-term samples during TA were not statistically different (p> 0.05), those levels of short-term samples were significantly different (p< 0.001). About 4.79 % of data in petrochemical industries exceed the occupational exposure limits (OELs) of benzene, 1 ppm. In a coal refining methods, about 15.7% exceeded the benzene OELs. The benzene concentrations in maintenance and start up stage of TA for petrochemical refineries were higher than those in a coal chemical refinery (p <0.01). These findings suggest that the coal chemical refining site requires more stringent work practice controls compare to petrochemical refining sites during TA processes. Personal protective equipments including organic respirators should be used by TA workers to protect them from benzene overexposure.

• The Journal of Fisheries Business Administration
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• v.31 no.1
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• pp.115-133
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• 2000

The policy of suppling tax-exempt fishery oil in Korea has a history of almost 40 years, which was initiated by the National Federation of Fisheries Cooperatives in 1965. In 1999 the volume of fishery oil supplied to the earning fishermen and fishing entrepreneurs amounted to 8,390 thousand DM, 500 billion won in total. This paper analyzes the oil supplying system to fishermen in Korea and shows that the structural obstacles to the stable provision of fishery oil lies in the ineffective bargaining power (fixing price). Provided that the NFFC as a buyer, which is not equipped with the storage facilities for oil bids for a unit-price contract of fishery oil, there exists a possibility of collusion among 5 local oil refineries corporations to influence the oil price, making it difficult to reach a resonable price of oil. Though the international bids and direct imports following the liberalization of oil imports would help lower the unit price, purchasing and importing the oil out of season at a lower price would not be guaranteed without the oil storage facilities. Furthermore, the current supply system of oil is quite vulnerable to the extraneous factors and, say when the oil price soars unpredictably, it is almost impossible to supply low - priced fishery oil to fishermen. The National Federation of Fisheries Association of Japan(Zengyoren), for instance, possesses 10 oil storage facilities, which had been built across the country during the last 20 years (1964-1984). The storage capacity of these facilities reaches 0.6million DM(by kind, 0.56million DM for A heavy oil, 38thousand D/M kerosene, 5thousand D/M for diesel fuel oil). Allowing no intermediary of production associations(fisheries cooperatives) the NFFA's capacity for keeping oil in reserve rises much higher. As these storage facilities can keep the oil amounting to as much as of 70 days demand in reserve, a stable supply of fishery oil on favorable terms is secured. In contrast with Japan case, unequipped with the storage facilities for fishery oil, Korea does not have much bargaining power for bringing down the price of fishery oil. To make matters worse, the oil storing capacity of the member cooperatives is the volume of only 8 days demand. In case the oil price rises, it is almost impossible to supply the oil to the fishermen at a price lower than the price risen.

• Journal of Environmental Policy
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• v.12 no.1
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• pp.75-100
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• 2013

Health damages such as pneumoconiosis and kidney damage, caused by environmental hazardous factors are being reported in health impact assessment conducted on environmentally vulnerable areas, including cement factories and refineries. Current legal system for relieving the environmental victims is not effective enough because the environmental health act does not specify the environmental hazardous factors to be considered for the relief. The aim of this study is to examine the problems of the existing system by making empirical analysis on health damages and afflicted people as well as on cases when afflicted people were able to be covered by remedy system. The results show that, insufficiencies of the relief system are due to the following reasons: First, current Environmental Health Act does not act well as a remedy system. Second, due to its unique nature of environmental health damage, it is hard to identify and prove the cause of health damage and unlawful actions of violators in the process of environmental dispute conciliation and lawsuits against polluters. This paper suggests following solutions on above mentioned problems. First, in defining the range and definition of environmental diseases, negative system should be used alongside with the current positive system. Second, we suggest adding the nature of public law to relief system, in order to ease the legal burden of proof. Third, in case when it is hard to identify the polluters and one cannot expect reliefs for their damage, it is possible to elevate the effectiveness of the relief measure by expanding scope of the search for possible environmental hazardous factors that caused the health damage. It is urgent to improve the relief system so as to secure the environmental rights of Koreans.