먼지 필터 막은 인간의 건강, 안전 및 환경 보호의 몇 가지 중요한 측면에 기여하기 때문에 인간의 삶과 다양한 산업에서 중요한 역할을 한다. 이 연구는 고온 조건에 대한 우수한 열안정성과 접착 특성을 가진 polysulfone@polyphenylene sulfide/polytetrafluoroethylene (PSf@PPS/ePTFE) 복합 먼지 필터 막의 개발을 제시한다. FT-IR 분석은 PSF 접착제가 PPS 직 물에 성공적으로 함침되고 ePTFE 지지체와의 상호 작용을 확인한다. FE-SEM 이미지는 향상된 섬유 상호 연결 및 PSf 농도 와 함께 접착력을 보여준다. PSf@PPS/ePTFE-5는 가장 적합한 다공성 구조를 보여준다. 복합 막은 400°C까지 예외적인 열 안정성을 보여준다. 박리 저항 테스트는 먼지 여과에 대한 충분한 접착력을 보여 공기 투과성을 희생시키지 않고 힘든 고온 조건에서 신뢰할 수 있는 성능을 보장한다. 이 막은 산업 응용 분야에서 유망한 잠재력을 제공한다. 더 나아가 최적화 및 응 용 가능성을 탐구할 수 있다.

This study was undertaken to investigate whether HEPA filter-equipped air purifiers can remove aerosolized virus, whether the removed virus can re-scatter through the filter, and how long the removed virus keeps its infectivity in the filter. For this investigation, six HEPA filter-equipped air purifiers produced by different companies were tested against PhiX174 and MS2 phages aerosolized by nebulizers. For viral detection from the air, LB agar plates covered with Escherichia coli hosts and an Andersen air sampler were used, and from the surface, the swab method was used. Both the aerosolized PhiX174 and MS2 viruses absorbed by the HEPA filters in the air purifiers were not detected from the air through filters or the surface of the outlet of the air purifiers. During the operation of the air purifiers at medium mode, the infectious viral concentration of these viruses in the HEPA filters decreased to 0%~12.3% as the time period passed. These results regarding infectious viral concentration differences were assumed to be due to the different wind speed and air volume among the six air purifiers. Based on observations over 5 days, the infectious viral concentration of the PhiX174 phage was 8,600 times lower when the air purifier was operated than when it was not operated. Overall, our results demonstrate that HEPA filter-equipped air purifiers can efficiently remove the two aerosolized viruses and the removed viruses in the HEPA filter could not re-spread and maintain their infectivity.

Rehabilitation work is required to increase well productivity, which decreases with the elapsed time of pumping owing to the clogging of the water well. Clogging causes not only a reduction in the well productivity but also a deterioration of the water quality. For unclogging and rehabilitating wells, several techniques are used such as brushing, air surging, surge blocks, and gas impulse. In this study, the high-pressure air impulse technique, which effectively and economically rehabilitates wells, was applied to a riverbank filtration site in Korea for the same objective. At most of the wells, the hydraulic parameters (transmissivity, storage coefficient, and specific capacity) were increased by the application of the high-pressure air impulse technique. The well loss change values also indicate an increase in the hydraulic parameters by the air impulse implementation. Thus, the high-pressure air impulse technique can be efficiently and economically applied to water and riverbank filtration wells for rehabilitating the decreased productivity.

This study was carried out to investigate the formaldehyde (FA) filtration pattern of additional media for indoor biofilter system. Dry pellet type activated carbon (PAC), activated clay (ACL), zeolite, diatomite, pumice and loess ceramic ball were tested. In the case of dry filter media, formaldehyde purification efficiency was the most excellent with activated clay and then was good with the activated carbon, diatomite, zeolite, and pumice order. PAC and ACL decreased the FA concentration with exponential pattern resulted from dynamic balance between emission and purification. Zeolite, diatomite, pumice, and loess ceramic ball showed high filtration rate at initial time and then increased FA concentration result from breakthrough. PAC, zeolite and diatomite could be recommended as additional filter media for biofilter system considering FA filtration and breakthrough characteristics. FA filtration and breakthrough characteristics were improved with wet media except PAC and ACL. In particular, purification performance improvement and breakthrough mitigation were higher in pumice and loess ceramic balls. PAC+ZEO mixing showed the most high purification performance and breakthrough mitigation in all mixing methods. Thus mixture of PAC with zeolite and vertical mixing could be recommended as additional filter media to improve the FA purification ability and pressure drop with indoor air biofilter system.

Under controlled conditions in an environmental chamber, 24 experiments were performed to compare the ability of a Variable-Air-Volume/Bypass Filtration System(VAV/BPFS) to remove indoor pollutants and to conserve energy with the ability of conventional Variable Air Volume(VAV) system. The specific conclusions of this paper were; first, the VAV/BPFS was more efficient than the VAV system in removing particulate matter, TVOC, and target VOCs. The total effective removal rate of PM for the VAV/BPFS was two times as high as that of the VAV system. The total effective removal rate of TVOC for the VAV/BPFS was 20 percent higher than that of the VAV system. Also each target VOC concentration was reduced by using the VAV/BPFS. Second, clean air delivery rate was increased by using VAV/BPFS due to additional filtration rate. Otherwise, the VAV/BPFS decreased outdoor supply air rate above 25 percent relative to the rate of VAV system. Third, total energy consumption by the VAV/BPFS was lower than that of the VAV system during the period with indoor thermal load, occupied time. The energy saving of the VAV/BPFS ranged from 11 to 16 percent. The VAV/BPFS improves indoor air quality more efficiently than the VAV system, and it reduced energy consumption. Retrofitting the VAV system with the VAV/BPFS was easy. The use of VAV/BPFS is, therefore, recommended for buildings with VAV system as well as for buildings at designing stage.

The purpose of this study was to investigate spatial distributions of total deposition. A total number 79 samples were collected at 17 sampling sites from September 1999 to January 2000. Total (=wet+dry) atmospheric depositions were collected by filtered deposition sampler at sampling site (the Western Part of Kyongsangnam Province). In addition, the deposition of soluble and insoluble fraction was also investigated to find a suitable simplified collection method for a long-term monitoring of total deposition. The total depositions were measured soluble amount(mm/month), insoluble amount(kg/km2/month), pH, conductivity(E.C.) and eight ionic components. The spatial distribution of deposition flux was to estimated by using a kringing analysis. The 17 sites mean fluxes of water soluble ionic components; SO42-, Cl-, NO3-, Na+, NH4+, K+, Mg2+, Ca2+ were 100.7～315.6kg/km2/month, 30.1～234.3kg/km2/month, 64.4～139.4kg/km2/month, 7.5～68.3kg/km2/month, 10.7～48.7kg/km2/month, 5.6～27.9kg/km2/month, 4.5～17.5kg/km2/month, 27.6～81.7kg/km2/month, respectively.