검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 19

        1.
        2019.02 KCI 등재 서비스 종료(열람 제한)
        Organic wastewater generated from polyester manufacturing processes was selected from H company to investigate the feasibility of anaerobic digestion that produces gases including methane. Bio Methane Potential (BMP) tests were conducted to measure the gas production and methane concentration for 7 process wastewater and 2 kinds of sludges from the H company. Also, along with monitoring pH and alkalinity during the anaerobic digestion process, the concentrations of COD and 1,4-dioxane were measured with 4 different operating conditions for N Emulsion (NE) and Ethylene Glycol (EG) wastewater. The BMP tests showed that 65% of methane was produced from NE and EG wastewater. This suggests that the organic wastewater from H company can be effectively treated by an anaerobic digester by which more than 90% of COD was removed.
        2.
        2015.12 KCI 등재 서비스 종료(열람 제한)
        To develop various usable water from coal seam gas (CSG) water that needs to be pumped out from coal seams for methane gas production, a feasibility study was carried out, evaluating and analysing a recent report (Coal Seam Gas Water Management Policy 2012) from Queensland State Government in Australia to suggest potential CSG water treatment options for fit-for-purpose usable water production. As CSG water contains intrinsically high salinity-driven total dissolved solid (TDS), bicarbonate, aliphatic carbon, Ca+2, Mg+2 and so on, it was found that appropriate treatment technologies are required to reduce the hardness below 60 mg/L as CaCO3 by setting the reduction rates of Ca+2, Mg+2 and Na+ concentrations, as well as TDS reduction. Also, Along with fiber filtration and membrane separation, an oxidation degradation process was found to be required. Along with salinity reduction, as CSG water contains organic compounds (TOC: 248 mg/L, C6 -C9: <20 mg/L and C10 - C36: <60 mg/L), compounds with relatively high molecular weights (C10 - C36) need to be treated first. Therefore, this study suggests a combined system design with filtration (Reverse osmosis) and oxidation reduction (electrolysis) technologies, offering proper operating conditions to produce fit-for-purpose usable water from CSG water.
        3.
        2015.11 KCI 등재 서비스 종료(열람 제한)
        A water reuse system was designed for a demonstration plant by combining fiber filtration and electrolysis. A discharged dye wastewater after treated with biomedia was used in this study. It was found that an additional removal of suspended solids (SS) was feasible with 2‐stage filtration while electrolysis was not effective. Also, CODcr and CODMn were not removed with 2 ‐stage filtration but electrolysis resulted in about 26.9% additional removal. This indicates that electrolysis play an important role in organic removal. Removal of T‐N and T‐P was negligible with 1 and 2‐stage fiber filtration and low‐level electrolyte. However, with 2000 ppm of electrolyte, their removal efficiencies were about 83.1 and 60%, respectively, suggesting that the removal rates are well associated with the electrolyte concentrations. With high‐level electrolyte, colority was removed about 82% while chlorine ions were removed only about 10%. Therefore, to treat underground water containing high‐level salinity in the follow‐up study, based on the results in this paper, a combined system with selection of additional unit process and reverse osmosis will be designed.
        4.
        2014.12 KCI 등재 서비스 종료(열람 제한)
        Taking sample processes from the combined heat and power plant in Busan Fashion Color Industry Complex, the characteristics and amounts of greenhouse gas (GHGs) emissions were analysed and calculated, respectively. Based on the results, environmental assessment was evaluated for recent 3 years. The amounts of GHG emissions from 2011 to 2013 were estimated at 182,750, 184,384 and 190,250 Ton.CO2eq/year, respectively. GHG emissions from stationary combustion sources were found to be more than 99 % of the total emissions. Also, the overall eco-efficiency indicator for environmental assessment was more than 1, suggesting that these results would be beneficial for GHG emissions allowance allocations.
        5.
        2014.11 KCI 등재 서비스 종료(열람 제한)
        Greenhouse gas (GHG) emissions from dye wastewater treatment processes were estimated by analysing their mass and energy balances, which were then used as baseline information for environmental assessment. The total GHG emissions from dye wastewater treatment plants were divided into direct emissions from the treatment processes and indirect ones from electricity usage. The amounts of CO2, CH4 and N2O emissions were calculated according to the Intergovernmental Panel on Clime Change (IPCC) guideline for the GHG target management system. For 3 years between 2011 and 2013, direct and indirect emissions were on average 8,742.7 and 7,892.0 Ton.CO2eq/year, respectively, with the former exhibiting 52.6 %. Also, compared to 2012, in 2013, the eco-efficiency indicator by the GHG emissions was found to be more than 1, suggesting that environmental quality was effectively improved.
        6.
        2014.08 KCI 등재 서비스 종료(열람 제한)
        Coal seam gas (CSG) production involves extracting methane from coal seams with ground water which is so called a primary by-product of this process, and is often rich in salts and other constituents. The predicted large volume and variable quality of this water make water management a topic associated with CSG production. In the past, the amount of this water used to be pumped into the vacant aquifer, or into the river during the life of individual production wells. Australian government make a strategies for management and beneficial use of the water. From this point of view, a detailed assessment has not been undertaken, it is necessary for water resource production to analysis the "Coal Seam Gas Water (CSG Water) Management Policy Study" published in Queensland, Australia.
        7.
        2013.04 KCI 등재 서비스 종료(열람 제한)
        A mass balance of process was calculated by using the analysis of basic unit and environmental assessment of all the processes of Busan fashion color industry cooperative that operates a combined heat and power plant and a bio treatment plant. The mass balance for the combined heat and power plant was done, based on boiler and water treatment processes while each unit reactor was used for the bio treatment plant. From the results above, a resource recycle network, a treatment flowchart for food waste water/wastewater treatment and a carbon reduction program were established.
        8.
        2013.03 KCI 등재 서비스 종료(열람 제한)
        For the purpose of evaluating the eco-efficiency(EE) on surplus heat generated from industrial process, techniques of life cycle assessment are adopted in this study. Because it can be indicated both environmental impacts and economic benefits, EE is well known as a useful tool for symbiosis network on the sustainable development of new projects and businesses. To evaluate environmental impacts, the categories were divided into two areas of resource depletion and global warming potential. It can be seen that environmental impact increased a little but much higher economic benefit on the company, environmental performance and economic value were improved on the apartment by the district heating, respectively. In result, eco-industrial park(EIP) project on surplus heat should be found sustainable new business because the EE was in the area of fully positively eco-efficiency and, moreover resource depletion was taken place than the reduction of greenhouse gas.
        9.
        2013.03 KCI 등재 서비스 종료(열람 제한)
        In this paper, an environmental assessment was carried out on the whole process of industrial business activities to establish a basic plan for climate change mitigation and energy independency. The whole process was divided into each discharge process in terms of water, air, solid waste, green house gases and refractory organic compounds. The flowcharts and basic unit of process were analysed for three years (2008-2010), being utilized as basic information for the life cycle assessment. It was found that the unit loading for the whole process significantly depends on changes in the operation rate change and highly concentrated wastewater inflow. About 35% of solid waste production was reduced by improving the incineration method with co-combustion in coal boiler, generating about 57% of electricity used for the whole process, and consequently reducing the energy costs. As the eco-efficiency index was found to be more than 1, compared to the previous years, it can be said that improvement in general has taken place.
        10.
        2012.05 KCI 등재 서비스 종료(열람 제한)
        Eco-efficiency considers both environmental impacts and economic values. It is a useful tool for communicating with stakeholders for business decision making. This study evaluated the eco-efficiency factor (EEF) for the energy network of a dyeing company that supplies surplus heat to a neighboring apartment during the night. This symbiosis network is one of the eco-industrial park (EIP) projects in Korea and aims to benefit local residents and the industrial complex by utilizing surplus heat. In this study, two categories were annualized. The first quantified environmental burden based on CO2 emissions and quantified product value in terms of steam sales. The second used a variety of environmental factors, such as fossil fuel, water and waste, to quantify environmental burden and used steam sales to quantify value. The EEF of the symbiosis network was 1.6, using the global warming impact, and determined using the multiple variable, was 1.33. This study shows that the EEF depends on variable details of environmental burden but the values of this project were very high contrast to other business or EIP project.
        11.
        2012.03 KCI 등재 서비스 종료(열람 제한)
        For the cost-effective biological nitrogen removal (BNR) process whose characteristics of influent have low COD/N ratios, the automatic control system for the addition of external carbon based on oxidation-reduction potential (ORP) data in an anoxic reactor has been developed. In this study, it was carried out with a pilot-scale Bardenpho process which was consisted of anoxic 1, aerobic 1, aerobic 2, anoxic 2, aerobic 3 tank and clarifier. Firstly, the correlation coefficient (R2) of the dosage of external carbon source and ORP value was about 0.97. Consequently, the automatic control system using ORP showed that the dosage of external carbon source was decreased by about 20% compared with a stable dosage of 75 mg/L based on the COD/N ratio of the anoxic influent.
        12.
        2011.12 KCI 등재 서비스 종료(열람 제한)
        Caustic (NaOH) solution is used to remove H2S from hydrocarbon streams in petroleum refining industry, gradually being, so called, spent sulfidic caustic (SSC) which has high levels of H2S and alkalinity. Thus, SSC can be used as an electron donor and a buffering agent for autotrophic denitrification. As SSC, however, contains some non-biodegradable organics, air stripping was conducted to remove the non-biodegradable organics. As a result, over 93 % of the non-biodegradable organics was removed within 30 min of aeration. Then, Na2S2O3·5H2O, methanol and organic matters, which are produced from a biodiesel production plant, were added to reform the air-stripped SSC and their products being referred to new sulfidic caustics (NSCs)Ⅰ, Ⅱ and Ⅲ, respectively. Thereafter, to investigate the effect of these products on the removal of COD and TN, these products were injected to a biological nitrogen removal (BNR) process, resulting in additional 44 % TN removal without noticeable increase in the effluent COD level. Therefore, it can be said that the BNR process is a promising option to treat NSC as demonstrated in this study whose results can be useful for developing resource recovery technologies.
        13.
        2010.11 KCI 등재 서비스 종료(열람 제한)
        A membrane bioreactor (MBR) was designed using polyvinylidene fluoride(PVDF)-type hollow fiber membrane modules with a treatment capacity of 10 ton/day. A pilot plant was installed in a sewage treatment plant and was operated with an intermittent aeration method which avoids any concentration gradient of suspended solids (SS) in the MBR. For continuous operation, the pilot plant was first tested with influent (mixed liquor suspended solid:MLSS of 1000-2000 mg/L) of aeration tanks in the sewage treatment plant. The MBR was pre-treated with washing water, 10% ethanol solution, 5% NaOCl solution and finally washing water, one after another. To demonstrate the effect of the MBR on sewage treatment, compared with conventional activated sludge processes, we investigated the relationships among permeate amount (LMH), change in operation conditions, influent MLSS level and sludge production. It was found that the optimum aeration rate and suction pressure were 0.3 m 3 /min and 30~31 cmHg, respectively. Under stable conditions in aeration, suction pressure, influent flow rate and drainage, the SS removal efficiency was more than 99.99% even when the MLSS loading rate changes. Compared with conventional activated sludge processes, the MBR was more effective in cost reduction by 27% based on permeate amount and by 51.5% on sludge production.
        14.
        2010.10 KCI 등재 서비스 종료(열람 제한)
        Since biodiesel as bioenergy is defined as ester compounds formed by esterification of animal/vegetable oils, in this study three vegetable cooking oils (market, waste and refined waste ones) were esterified by reactions of alkali catalyst and immobilized enzyme. The fatty acid composition of the formed ester compounds was analyzed to investigate the feasibility of biodiesel production. By lipolysis (i.e, hydrolysis of Triglyceride (TG)), all three vegetable oils used in this study were found to produce Diglyceride (DG), Monoglyceride (MD) and Fatty acid ethylester (FAEE). However, the amount of produced FAEE (which can be used as an energy source) was in the increasing order of market cooking oil, waste one and refined waste one. With NaOH catalyst, FAEE was produced about 24.92, 17.63 and 11.31 % for the respective oils while adding Lipozyme TL produced FAEE about 43.54, 38.16 and 24.47 %, respectively. This indicates that enzyme catalyst is more effective than alkali one for transesterification. In addition, it was found that the composition of fatty acids produced by hydrolysis of TG was unchanged with alkali and immobilized enzyme reactions. Thus it can be expected that stable conditions remain in the course of mixing with gasoline whose composition is similar to that of the fatty acids.
        15.
        2010.04 KCI 등재 서비스 종료(열람 제한)
        The pressure drop through pulse air jet-type bag filter is one of the most important factors on the operating cost of bagfilter houses. In this study, the pilot-scale pulse air jet-type bag filter with about 6 ㎡ filtration area was designed and tested for investigating the effects of the four operating conditions on the total pressure drop, using the coke dust collected from a steel mill factory. When the face velocity is higher than 2 m/min, it is not applicable to on-spot due to the increase of power expenses resulting from a high-pressure drop, and thus, 1.5 m/min is considered to be reasonable. The regression analysis results show that the degree of effects of independent parameters is a order of face velocity > concentration > time > pressure. The results of SPSS answer tree analysis also reveal that the operation time affects the pressure drop greatly in case of 1 m/min of face velocity, while the inlet concentration affects the pressure drop in case of face velocity more than 1.5 m/min.
        16.
        2005.12 KCI 등재 서비스 종료(열람 제한)
        Basic dyes, Rhodamine 6G(R6G), Rhodamine B(RB), and Methylene Blue(MB), dissolved in water were used to investigate single-component adsorption affinity to the pearl layer fractionated according to the size. Unfractionated pearl layers were also used as adsorbents for the R6G and RB. The Langmuir and the Redlich-Peterson(RP) models were used to fit the adsorption data, and the goodness of fit was examined by using determination coefficient(R2) and standard deviation(SSE). The 3-parameter RP model was found to be better in describing the dye adsorption data than the 2-parameter Langmuir model, as can be expected from the number of parameters involved in the model. The adsorption affinity to the fractionated pearl layer was higher than that to the unfractionated layer. The affinity order to the fractionated Conchiolin layer was found to be R6G > MB > RB. Furthermore, the dye adsorption capacity of the various types of pearl layer was found to be in the order, the fractionated pearl > powdered pearl > unfractionated pearl, exhibiting different adsorption isotherms according to the types of layer used in the study.
        17.
        2005.12 KCI 등재 서비스 종료(열람 제한)
        In order to develop a dye coloring technology on Conchiolin layer in cultured pearls, appropriate dyes were selected, their solubilities in various solvents were studied, and adsorption and desorption experiments were performed. Solubilities of several basic dyes known to suitable for the pearl coloring, i.e., Rhodamine 6G(R6), Rhodamine B(RB) and Methylene Blue(MB), in several solvents (distilled water, methanol, ethanol, and acetone) were investigated. Among these dyes, R6 was chosen as a dye for single component adsorption and desorption experiment due to the relatively good solubility in various solvents tested. Solubilities of dyes were judged to be enough to color the pearls since dye concentrations in pearl coloring are, in general, not so high. The internal surface area of the pearl layer is believed to be directly related to the dye adsorption; the single-point internal surface area of the pearl layer measured at the nitrogen relative pressure of 0.3 was found to be 0.913㎡/g, and the BET internal surface area, 1.01㎡/g. The most probable diameters of micropores and macropores were found to be 40Å and 5000Å, repectively, from the pore size distribution d/ata. Adsorption isotherm was well fitted to the Langmuir isotherm model, resulting in q=1.62C/1+1.09C˙
        18.
        2004.04 KCI 등재 서비스 종료(열람 제한)
        Waste water-soluble cutting oil was treated with W1 type #1 and W1 type #2. The properties of the original water-soluble cutting oil were pH=10.4, viscosity=1.4cP, CODcr=44,750 ppm, and TOC=10,569 ppm. However, the properties of the oil used for more than 3 months were changed to pH=7.82, viscosity=2.1cP, CODcr=151,000 ppm, and TOC=74,556 ppm. It might be attributed to the fact that molecular chains were cut due to thermal oxidation and impurities such as metal chips were incorporated in to the oil during the operation processes. To prevent the putrefaction of oil, the sterilization effect of ozone and UV on the microorganism in the oil was investigated. Ozone treatment showed that 99.99% of the microorganism was annihilated with 30 minutes contact time and 60 minutes were necessary for the same effect when UV was used. Ozone treatment could cut molecular chains of the oil due to strong sterilization power, which was evidenced by the increase of TOC from 25,132 ppm at instantaneous contact to 28,888 ppm at 30 minutes contact time. However, UV treatment didn't show severe changes in TOC values and thus, seemed to cause of severe cut of molecular chains. When the activated carbon was used to treat the waste water-soluble cutting oil, TOC decreased to 25,417 ppm with 0.1g carbon and to 15,946 ppm with 5.0g carbon. This results indicated that the waste oil of small molecular chains could be eliminated by adsorption. From the results, it could be concluded that these treatment techniques could be proposed to remove the waste oil of small molecular chains resulting in the degradation of the oil properties. In addition, these experimental results could be used for the correlation with future works such as investigation of the molecular distribution according to the sizes, lengths, and molecular weight of the chains.
        19.
        1996.02 KCI 등재 서비스 종료(열람 제한)
        A recycling soap was prepared from non-cooking oils. The effects of physical and chemical properties of the recycling soap on biodegradation are expected to be different due to the thermal histories of the non-cooking oils. Therefore, the biodegradation rate of the recycling soap was studied by using Klebsiella pneumoniae(K. pneumoniae), and the growth rate of K.pneumoniae in soap solution was observed. The biodegradation rate of the recycling soap appeared to be slower as the thermal histories of the non-cooking oils became larger. This might be resulted from hydrolysis, in which the ester bonds in the oils are broken to produce hydroxyl group. It was also observed that the growth rate of the microorganism decreased with the increase in the thermal histories of the oils. As a result, it is desired that recycling soap should be produced from the non-cooking oils with the proper ranges of thermal histories to reduce water contamination. The non-cooking oils with larger thermal histories are considered to be recycling through the cracking process before used.