• Journal of Environmental Science International
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• v.20 no.10
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• pp.1233-1241
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• 2011

The main objective of this experimental investigation was $CH_4$ recovery from biogas generated in municipal and wastewater treatment plant. The polysulfone hollow fiber membrane was prepared in order to investigate the permeation properties of $CH_4$ and $CO_2$. Permeability of $CO_2$ in Polysulfone membrane was 11-fold higher than of $CH_4$ gas. A membrane pilot plant for upgrading biogas was constructed and operated at a municipal wastewater treatment plant. The raw biogas contained 66 ~ 68 Vol % $CH_4$, the balance being mainly $CO_2$. The effect of the operating pressure of feed and permeate side and feed flowrate on $CH_4$ recovery concentration and efficiency were investigated with double stage membrane pilot plant. The $CH_4$ concentration in the retentate stream was raised in these tests to 93 Vol % $CH_4$.

• Computers and Concrete
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• v.8 no.6
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• pp.617-629
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• 2011

In this investigation, reservoir sediment and municipal sewage sludge were sintered to form the artificial lightweight aggregates. The sintered aggregates were compared with the commercialized lightweight aggregates to in terms of potential alkali-silica reactivity and chemical stability based on analyses of their physical and chemical properties, leaching of heavy metal, alkali-silica reactivity, crystal phase species and microstructure. Experimental results demonstrated that the degree of sintering of an aggregate affected the chemical resistance more strongly than did its chemical composition. According to ASTM C289-94, all potential alkali-silica reactivity of artificial lightweight aggregates were in the harmless zone, while the potential reactivity of artificial lightweight aggregates made from reservoir sediment and municipal sewage sludge were much lower than those of traditional lightweight aggregates.

• 한국연소학회:학술대회논문집
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• 2001.11a
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• pp.137-141
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• 2001

The behavior of Cl is important to prevent HCl exhausted by incineration of RDF. Because RDF is composed of municipal wastes, its calorific value is very various. Thus components of RDF are to be analyzed and elemental analyze and calorific value are to be done. And in order to find the behavior of Cl during RDF combustion, Cl included in exhaust gas and ash is captured and analyzed. RDF which made by municipal and $Ca(OH)_2$ with regular ratio(Ca/0.5Cl) is incinerated in fluidized bed combustor. Cl included in exhaust gas and fly ash is captured and analyzed. Finally the change of Cl concentration included in exhaust gas and ash is analyzed and the behavior of Cl is investigated.

• Journal of environmental and Sanitary engineering
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• v.14 no.2
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• pp.105-112
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• 1999

The removal characteristic of BOD, COD,T-N, and T-P was investigated in municipal wastewater treatment with anoxic and membrane submerged aerobic reactor. It was found that BOD and COD removal rate were obtained 90% and 92%, respectively, for 90 days operation. BOD and COD loading rate did not affect to the removal efficiency because MLSS concentration in aerobic tank was highly maintained.In the case of first reactor operated with anoxic and second reactor operated as aerobic, T-N, T-P removal rate were obtained 93% and 99% respectively.It was shown that removal efficiency could be maintained stable due to the complete removal of SS and sludge production decreased with increasing of sludge retention time.

• Hwankyungkyoyuk
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• v.23 no.3
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• pp.126-139
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• 2010

The purpose of this study was to investigate the perception of designating the environmental education center for researcher, teacher, professor, NGOs. The questionnaire was composed of the introduction of designation, human resources, function, operation, facilities and 131 participated in this survey. According to the results of the study, First, environmental education center is divided into four types(national, municipal A, municipal B, private environmental education center). Second, according to the type, It is necessary to put the difference in each center. Third, the majors and career about environmental education are needed for staff.

• Korean Journal of Veterinary Research
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• v.11 no.2
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• pp.141-143
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• 1971

The serum alkaline phosphatase activity was determined with 64 Korean cattles in different sexe and age groups, using p-nitrophenylphosphate as the substrate. The results obtained were as follows: 1. The mean value of serum alkaline phosphatase activity in Korean cattle was $1.78{\pm}0.21$ Bessey-Lowry units/ml, and $1.71{\pm}0.21$ units/ml. in female and $1.86{\pm}0.21$ units/ml. in male, respectively. 2. The serum alkaline phosphatase activity decreased with age from 4 years group. 3. No statistical significance was recognized among the sexes, but difference among the age groups was found to be highly significant.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.2
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• pp.65-73
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• 2005

After the introduction of Volume-based Waste Fee System for municipal wastes, the disposal of food wastes became an issue an issue in society. Concerted efforts among government agencies have been made to manage food wastes separately from municipal wastes. For example, the Ministry of Environment, the Ministry of Agriculture and Forestry, and the Ministry of Health and Welfare established the '5-year('98-'02) Basic Plan for Recycling Food Wastes' in September 1998. Also changes in the waste disposal system has been sought, aiming at the Resource-circulating Society.

• Journal of Industrial Technology
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• v.22 no.B
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• pp.103-108
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• 2002

This research was performed to investigate the generation and physico-chemical characteristics of municipal solid wastes. The results were as follows: i) The generation rate and bulk density were 0.157 kg/cap/d and 147.8 g/L in residential zone, respectively. In non-residential zone, the generation and bulk density were 1.71 kg/cap/d and 85.6 g/L, respectively. Consequently, bulk density of non-residential zone was lower than that of residential zone. ii) The wastes consisted of 90% of combustibles and 10% of incombustibles in residential zone. And the wastes from non-residential zone was composed 85% of combustibles and 15% of incombustibles. iii) Water content was estimated at 47~50% in residential zone and restaurants. In non-residential zone, except restaurants, water content was in the range of 10~30%. Ash content was nearly 10% in overall zone.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.4
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• pp.534-541
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• 2003

To investigate the combustion characteristics in a low-pollutant municipal waste incinerator, the generalized multi-block simulation code that can be applied to turbulent reacting flow with gaseous hydrocarbon fuel in a 3D complex geometry has been developed with nongray radiation effects. To deal with the complex geometry, structured multi-block method and the scheme which treats interfaces implicitly are adopted. The developed code is validated through various engineering problems such as curved duct flow, driven cavity flow, gray multi-block radiation, nongray radiation. and combustion in a incinerator.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.650-654
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• 2001

To utilize municipal solid waste incineration ash as useful resources in Korea, studies on the present state of production and management of incineration ash and its effects on environment were made. And, it was intended to analyze the management conditions of incineration ash in many foreign countries and reflect them in domestic incineration ash policy. Korean incineration ash policy is based on the control of waste production, considering the difficulties in securing landfills and the small size of national land, and will be changed into recycling- and incineration-centered one. Furthermore, studies on the stabilization and recycling of incineration ash should be continuously conducted to overcome the concerns about environmental pollution.