• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.519-525
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• 2008

Biodegradation of toluene, styrene and hydrogen sulfide as model compounds of volatile organic compounds and odor from waste gas was investigated experimentally in a biotrickling filter. This study focussed on the description of experimental results with regard to operating conditions. The effect of varying $H_2S$ load rate and inlet concentration was investigated under autotropic and mixotropic environmental conditions. The $H_2S$ removal efficiencies of greater than 99% were achieved at $H_2S$ loads below $10g/m^3{\cdot}hr$ for each environment. It was observed that the maximum elimination capacity of mixotrophic filter was achieved a little greater than the one of autotrophic filter. The biofiltration of toluene and styrene in trickling bed was examined under different gas flow rates, load rates, and inlet concentrations. Below $40g/m^3{\cdot}hr$ of toluene loading, the elimination capacity and loading were identical and it was completely destroyed. In high loading of toluene, the biotrickling filter was operated at its maximum elimination capacity. In the inlet concentration of 0.2, 0.5, and $1.0g/m^3$, the maximum elimination capacity of toluene showed 40, 45, and $60g/m^3{\cdot}hr$, respectively. After a short adaptation period, it was demonstrated that the results of styrene in originally toluene adapted bioreactor was similar with the ones of toluene. However, the performance of filer for styrene is generally a little lower than for toluene. The operating conditions (including liquid flow rate etc.) allowing the highest removal efficiency should be determined experimentally for each specific case.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.474-484
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• 2005

Biological treatment is a promising alternative to conventional air pollution control methods. Bioreactors for air pollution control have found most of their success in the treatment of dilute and high flow waste air streams containing volatile organic compounds and odor compounds. They offer several advantages over traditional technologies such as incineration or adsorption. These include lower treatment costs, absence of formation of secondary pollutants, no spent chemicals, low energy demand and low temperature treatment. The most widely used bioreactor for air pollution control is biofilter, but it has several limitations. In the past years major progress has been accomplished in the development of vapor phase bioreactor, in particular biotrickling filters. Biotrickling filters are more complex than biofilters, but are usually more effective, especially for the treatment of compounds which are difficult to degrade or compounds that generate acidic by-products. While the level of understanding of biotrickling filtration process for VOCs still remains limited, the evident success of biotreatment of VOC in air stimulated the pursue of acitve research. This paper presents fundamental and theoretical/practical aspect of air pollution control in biotrickling filter. Special emphasis is given to the operating parameters and the factors influencing performance for air pollution control in biotrickling filter.

• Journal of Korea Soil Environment Society
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• v.1 no.1
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• pp.11-17
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• 1996

Trichloroethylene(TCE) is the organic compound which is used variously at the industrial areas. It contaminates soils and groundwater by leaked storage tank, careless treatment in field and the effluent from waste landfills. This study was carried out to identify adsorptive behavior of TCE by soil. Batch experiments were conducted at different soil-organic matter content and lime treatment to determine Freundlich isothermal adsorption equation constant, k and n, for TCE. Sewage sludge cake was applied to make different soil-organic matter content with the level of Oton/ha(S1), 50ton/ha(S2), 100ton/ha(S3). Lime(calcium hydroxide) was treated with the level of 2ton/ha, 4ton/ha, 6ton/ha, 10ton/ha. Freundlich isothermal adsorption equations obtained from experiment with sewage sludge cake were as follows (on condition that the level of TCE applied to soil ranged from 0.5ng/g soil to 2.5 ng/g soil.) : S1 :x/m = 0.393 $C^2$, S2 : x/m = 0.436 $C^2$, S3 : x/m = 0.636 $C^2$Value of k was increased in higher order of 51, 52, 53 with increased level of sewage sludge cake application. From this results, soil which was applied higher level of sewage sludge cake had a good ability on TCE adsorption. With increased the level of lime application, pH of the soil was increased and the ability of the soil in TCE adsorption was decreased.

• Plant Journal
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• v.12 no.1
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• pp.29-36
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• 2016

It is becoming increasingly important to make use of alternative energy source. because It is not able to rely on only fossil fuel for the recent increasing demand of energy consumption. With this situation, lots of studies for utilizing low grade energy such as industrial waste heat, solar energy, and geothermal energy have been conducted. The aim of this study is to predict the operation characteristics of working fluid by using performance analysis program (ThermoFlex) through the system analysis which is not mixing district return water but using ORC(Organic Rankine Cycle, hereinafter ORC) as a downstream cycle when accumulating district heating (hereinafter DH). In this study, We conducted the performance analysis for the case which has the district heating water temperature($120^{\circ}C$) and Flow rate of $163m^3/h$ (including District Heating return water flow), and examined several working fluid which is proper to this temperature. The case using R245fa (which is the best-case) showed 269.2kW power output, 6.37% efficiency. Additionally, Cut down on fuel was expected because of the boiler inlet temperature increase by being Formed $57.3{\sim}85^{\circ}C$ in a temperature of district heating return water, depending on a pressure change of a condenser in ORC system.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.5
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• pp.517-532
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• 2010

After establishment of Banwol industrial complex in 1987, Ansan city becomes the largest industrial sector development in Gyeonggi-do, Korea. As the population and industrial activity grow over this region, toxic air pollutants, particularly POPs (Persistent Organic Pollutants) from various emission sources have been major public concerns. Air samples for POPs monitoring were collected at the industrial sites ($A_2$), residential sites ($B_1$, $B_2$), commercial site (C), and rural/remote site (D) of the area of Ansan during 2008 with a prolonged industrial sampling site $A_1$ from 2001 to 2008. All samples were analysed for 2,3,7,8 substituted-polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs) and dioxin like polychlorinatd diphenyls (dl-PCBs). In site $A_1$, a steady decline of their concentrations from 2003 to 2008 was observed due to the reinforced emission guideline from waste incinerators. The average concentration of the PCDD/Fs and dl-PCBs ranged between 0.118 pg-TEQ/$m^3$ (rural/remote site D) and 0.532 pg-TEQ/$m^3$ (industrial area $A_2$). These level were generally consistent with previous studies in Gyeonggi-do, while higher than other places. Most of PCDD/Fs congener were partitioned into particle phase, whereas dl-PCBs were partitioned into gas phase. The logarithm of gas-particle partition coefficient $K_P$ of dl-PCBs and PCDD/Fs were well correlated with sub-cooled liquid vapor pressure $P_L$. The slope $m_T$ of log $K_P$ versus log $P_L$ for PCDD/Fs (-1.22) and dl-PCBs (-1.02) in industrial area ($A_2$) were high compared to other residential/commercial area. It suggests that this area was likely influenced by the direct emission source of PCDD/Fs and dl-PCBs. To simulate the partition of PCDD/Fs and dl-PCBs between gas and particle phase, Junge-Pankow model ($P_L$-base) and $K_{oa}$ model were applied. It was found that J-P model was more suitable than the $K_{oa}$ model in this study.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.44-63
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• 2000

Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.

• Carbon letters
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• v.22
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• pp.81-88
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• 2017

In the present study, biomass-based lignin was extracted from industrial waste black liquor and the extracted lignin was characterized by means of attenuated total reflectance-Fourier transform infrared spectroscopy and $^1H-nuclear$ magnetic resonance spectroscopy. The extracted lignin was carbonized at different temperatures and then activated with steam at $850^{\circ}C$. The extracted lignin in powder state was transformed into a bulky carbonized lignin due to possible fusion between the lignin particles occurring upon carbonization. The carbonized and then pulverized lignin exhibits brittle surfaces, the increased thermal stability, and the carbon assay with increasing the carbonization temperature. The scanning electron microscopic images and the Brunauer-Emmett-Teller result indicate that the steam-activated carbon has the specific surface area of $1718m^2/g$, which is markedly greater than the carbonized lignin. This study reveals that biomass-based activated carbon with highly porous structure can be produced from costless black liquor via steam-activation process.

• Applied Chemistry for Engineering
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• v.18 no.4
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• pp.303-313
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• 2007

Various commercial catalysts used in chemical related applications have been disposed as an industrial waste when the catalytic activity of catalysts is not good enough to achieve an optimum yield. In addition, the amount of disposed three way catalysts (TWC) has been continuously increased. Considering the physicochemical, environmental, and economical characteristics, the deactivated spent catalysts can be treated in several alternative ways such as regeneration, recycling, and disposal. In view of the environmental and economical matters, the spent catalyst should be regenerated and used for the various purposes, although its activity is not as good as a fresh catalyst. On the other hand, spent catalysts containing noble and metal oxides can be applicable for the catalytic oxidation of volatile organic compounds (VOCs) by applying the proper treatment method. Therefore in this review the quantity of the spent catalysts and the available regeneration methods for the spent catalysts are briefly summarized and especially the proper regeneration method for applying the catalytic oxidation of VOCs and its results are introduced.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.4
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• pp.616-624
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• 2018

In this study, a previous DNPH (2,4-dinitrophenylhydrazine) coupled with high performance liquid chromatography (HPLC) method to measure the concentration of formaldehyde in ambient and source environments has been improved. To improve the disadvantage of the previous HPLC method, an appropriate composition ratio of mobile phase (water: acetonitrile (ACN)) was determined and an isocratic analysis was conducted. Furthermore, limit of detection (LOD), limit of quantitation(LOQ), accuracy, and precision were investigated to verify the reliability of the analytical conditions determined. Finally, samples of exhaust gases from five different industrial facilities were applied to HPLC analytial method proposed to determine their formaldehyde concentrations. The appropriate composition ratio of the mobile phase under the isocratic condition was a mixture of water(40%) and ACN(60%). As the volume fraction of the organic solvent ACN increases, retention time of the formaldehyde peak was reduced. Detection time of formaldehyde peak determined using the proposed isocratic method was reduced from 7 minutes(previous HPLC method) to approximately 3 minutes. LOD, LOQ, accuracy, and precision of the formaldehyde determined using standard solutions were 0.787 ppm, 2.507 ppm, 93.1%, and 0.33%, respectively, all of which are within their recommended ranges. Average concentrations of the formaldehyde in five exhaust gases ranged from 0.054 ppm to 1.159 ppm. The lowest concentration (0.054 ppm) was found at samples from waste gas incinerator in a bisphenol-A manufacturing plant. The highest was observed at samples from the absorption process in manufacturing facilities of chemicals including formaldehyde and hexamine. The analytical time of the formaldehyde in ambient air can be shortened by using the isocratic analytical method under appropriate mobile phase conditions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.27-33
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• 2016

Phenolic resin has excellent heat resistance and good mechanical properties as a thermosetting resin. However, its thermosetting characteristics cause it to produce a non-recyclable waste in the form of sprue and runner which is discarded and represents up to 15~20% of the overall products. Forty thousand tons of phenolic resin sprue and runner are disposed of (annually). The (annual) cost of such domestic waste disposal is calculated to be 20 billion won. In this study, discarded phenol resin scraps were pulverized and treated by silanes to improve their interfacial adhesion with HDPE. The sizes of the pulverized pulverulent bodies and fine particles were (100um~1000um) and (1~100um), respectively. The pulverized phenol resin was treated with 3-(methacryloyloxy) propyltrimethoxysilane and vinyltrimethoxy silane and the changes in its characteristics were evaluated. The thermal properties were evaluated by DSC and HDT. The mechanical properties were assessed by a notched Izod impact strength tester. When the silane treated phenol resin was added, the heat distortion temperature of HDPE increased from $77^{\circ}C$ to $96^{\circ}C$ and its crystallinity and crystallization temperature also increased. Finally, its impact strength and tensile strength increased by 20% and 50%, respectively, in comparison with the non-treated phenol resin.