• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.194-195
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• 2005

방사선관리구역 내에서 발생되는 많은 양(발전소별 연간 약$100{\sim}700$개 정도)의 사용 후 공기정화 필터는 고체 폐기물 드럼의 단면적 보다 넓어 별도로 필터를 압축하거나 분해 작업 없이는 폐기물로 직접 처리가 곤란하다. 처리 시 많은 양의 분진이 발생하여 작업자의 내부피폭 가능성 및 많은 양의 고체 폐기물이 발생할 수 있는 잠재성이 있어 시료분석 결과 오염된 필터 내지는 바로 드럼 처리하여 내부 피폭 가능성을 미연에 방지하고 필터 프레임은 재사용을 유도하여 폐기물 저감화, 작업환경 개선 및 경제적인 이익을 창출할 수 있다. 영광 3발전소와 울진 3발전소의 경우 타 발전소에 비해 방사선관리구역 내 공기정화 처리기의 설치수량이 많아(약 700개/년) 공기정화필터가 매년 다수 발생되고 있으며, 이를 전량 드럼 처리 시 고체폐기물 드럼이 더 발생하게 되어 영구처분비용의 증가를 초래하게 된다. 발전소 전체적으로는 약 3,500개/년의 폐필터가 발생되고 있다. 이렇게 발생되는 공기정화필터의 프레임을 재사용함으로써 그 효과는 1) 알루미늄을 포함한 유리섬유를 드럼처리 시 고체방사성 폐기물드럼 생성량 감소 2) 프레임 재사용으로 인한 예산절감 효과 3) 폐필터 분해작업 시 분진에 의한 작업자 체내${\cdot}$외 피폭방지와 작업장 오염 확산 방지 및 환경 개선 4) 작업시간 단축 및 소요인력 감소 효과를 볼 수 있다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.3
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• pp.257-265
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• 2007

Spent filter wastes of about 1,000 units (200 L) have been stored in the waste storage facility of the Korea Atomic Energy Research Institute since its operation. At the moment, to secure space in a waste storage facility as well as to efficiently manage spent filter wastes, it is necessary to conduct a compaction treatment of these spent filters, and finally, to repack the compacted spent filters into a 200 liter drum. To do that, the spent filter wastes were first classified according to their generation facilities, their generation date and their surface dose rate by investigating the inventory of the spent filters. In order to repack a compacted spent filter in a 200 liter drum, it is first necessary to conduct a radionuclide assessment of a spent filter before compacting it. Therefore, after taking a representative sample from a spent filter without a dismantlement, the nuclide analysis for it will be conducted. And then, after putting a spent filter into a regular drum by conducting the columnar shaping of the hexahedral form of a spent filter, the compaction treatment of the shaped spent filter will be conducted by vertically compacting it.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.914-919
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• 1998

This study was conducted to evaluate the purification efficacy by filter and ultra violet (UV) irradiation against inlet and outlet seawater of the land based fish farm. Purification efficacies for inlet seawater (50$\ell$/min) has been examined with filter of 60$\mu$m pore size and UV irradiation at an average dose 0.5 mWS/$cm^2$ for 5 months. For outlet seawater filter of 90 $\mu$m pore size only was used. Temperature, salinity, pH, $NO_3-N,\;NO_2-N,\;NH_4-N,\;PO_4-P$, DO and COD of inlet and outlet seawater in the system were not influenced. However, the removing rate of suspended solid and turbidity of inlet seawater were appeared to be $48.7\~65.6\%$ (average $51.9\%$) and $33/3\~42/5\%$ (average $34.8\%$) after passing through screen filter respectively. Also, germicidal efficiency to the total bacteris and Vibrio species were $16.7\~20.2\%$ (average $19.2\%$) $20.0\~21.9\%$ (average $20.9\%$) respectively after passing through UV irradiation. After passing through drum filter of 90$\mu$m pore size, suspended solid and turbidity of outlet seawater were appeared to be $42.7\~52.6\%$ (average $46.9\%$), $27.7\~29.9\%$ (average $28.3\%$), respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.908-913
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• 1998

The productivity of land based seawater fish farm has been decreased because of unexpected outbreaks of diseases caused by the contaminated inlet seawater. Sometimes unfiltered/untreated outlet seawater from the land based seawater fish farm has created serious environmental problem. In the needs of treatment systems for the inlet and outlet seawater, the researchers have developed two different systems, The purpose of this study is to design and test two treatment systems, the screen filter for inlet seawater and drum filter for outlet seawater, on the basis of concept of system design and automatization. After developing two systems, an experiment has been conducted with two systems and collected data to improve design and efficiency of the system. In this study, detailed design and efficiency of the system could be improved by the programmable logic controller (PLC).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.3
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• pp.442-450
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• 1994

In this paper, the tracking of SFH/MFSK signals by using a paeallel correlator and a bank of BPF which is implemented by DFT recursively is studied. During symbol period, M-ary signal`s spectrum is analyzed by the step of n multiple of sampling period. The bank of BPF output which is stored for hop duration input to the parallel correlator. The time difference of the receiver and the transmitter is corrected by using sampling position and correlation time at which the largest output of correlator is generated. Syncronization signal detection rate and distribution of the largest output of correlator are evaluated by computer simulation in HF channel evironments for the performance analysis of proposed tracking method.

• KSBB Journal
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• v.21 no.3
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• pp.188-193
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• 2006

A new type of biofilter, a rotating drum biotrickling filter(RDBF), was developed and operated for the removal of styrene from industrial waste gas. The porous polyurethane foam sheet was used as a packing materials for the RDBF and a pure culture of Gram-positive bacterium Brevibacillus sp. SP1 was used as an inoculum. The reactor showed a short start-up period of 18 days, during which uniform biofilms were developed on the packing. During a steady operation at an incoming styrene concentration of $200ppm_v$ and a retention time of 0.5 min, a high and stable removal of styrene over 95% was observed. The maximum elimination capacity was estimated to be $125g/m^3{\cdot}hr$. The outstanding performance was attributed to an efficient gas-liquid mass transfer and the appropriate supply of nutrient solution to the biofilm microorganisms on the packing by the rotation of the drum.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.10a
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• pp.251-255
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• 2002

Eutrophic matters accumulated on the bottom of sea, river and lake cause red tide phenomenon in ocean and outbreak green algae in river and lake. Systems are developed to remove the noxious deposit. But the existing systems remove not only the eutrophic matters but also natural materials, sand, pebbles etc. that should remain at the bottom. This paper describes a new system that can safely, and economically take away the noxious deposit in underwater. High pressure water jet is used to induce vortices in the triangular suction section, and air-lifting pump to lift up the deposit. The mixture of the water and deposit is filtered through the drum filters. An under camera shows the under water situation along the moving direction of the system that is controlled by a remote operator. This remote controlled moving system obliterate the necessity of the diver that usually costs high. The experimental results show the effectiveness of the suggested system.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.109-116
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• 2003

The amount of radioactive waste is expected to be increased continuously because of the rapid growth of the domestic nuclear industry, full power operation of the HANARO reactor and the increased research activities of the nuclear fuel cycle. Accordingly the efforts are focused to achieve the handling of radioactive waste in safe and reduce the volume of radioactive waste. The PIEF is carrying out the PIE (post irradiation examination) of spent fuel rods related to the identification of cause defect and evaluation of integration safety. This study describes the technologies and experiences of compaction, shredding and cutting of the solid radioactive waste used in the PIE. The quantity of the high level waste was reduced by 1/12 using the 100-ton compressor installed in hot-cell. Also middle and low level waste was reduced by 1/8 using the 60-ton compressor installed in intervention area. Plastic drums were shredded by crusher to be compacted in the ratio of 1/5, used filters in the ratio of 1/6 and the number of drum is also reduced by cutting procedure for the non-volatile materials such as metal.

• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.1
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• pp.62-69
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• 2000

The study was performed to apply the algae removal system to coagulation-filtration process for minimize the damage to screen interruption of water treatment plants and died of fish by algae bloom on freshwater. Sample used Nokdong river water and Alkalinity, turbidity, chlorophyll-a and pH measured using Jar test and drum filter for coagulation-filtration process to determine optimum coagulation condition. A jar test apparatus and laboratory reactor were used in this study. The highest removal efficiency was observed when condition of flocculation time, coagulant dosage, drum filter rpm and chlorophyll-a concentration were to be 5min, 5mg/ℓ, 3rpm and 90㎍/ℓ, respectively. The average removal efficiencies measured of chlorophyll-a and turbidity using Alum were 50～60% and 30～50%, respectively. PAC was more effective than Alum in removal chlorophyll-a about 20%.