PTFE 멤브레인이 코팅된 여과백을 이용한 여과집진장치의 미세먼지 집진특성에 관한 연구

국문 초록 (Abstract)

근래에 미세먼지가 대기환경 관련하여 이슈가 되고 있으며, 초미세먼지의 효과적인 집진을 위하여 대용량화가 용이한 여과집진장치가 상업적으로 사용될 수 있는 지에 대한 평가가 필요하다. 본 연구에서 여과집진장치 관련 다양한 설계 및 운전 조건에 따른 필터 전후단 발생 압력손실 및 집진효율과 같은 집진 특성을 평가하기 위하여 소형 여과집진장치를 제작하여, 반도체 제조 공정에서 배출될 수 있는 실리카 성분으로 다양한 입도범위를 갖는 먼지를 대상으로, 실린더 형상으로 제작된 PTFE 재질의 부직포 여과백 또는 PTFE 멤브레인이 코팅된 PTFE 재질의 여과백을 이용하여, 주요 운전 변수 여과속도, 투입 먼지량, 탈진유형 등의 변화조건에서 PTFE 멤브레인 유무에 따른 영향을 고찰함으로 미세먼지 집진을 위한 여과집진장치의 적용 가능성 평가를 위한 실험을 수행하였다. 실험결과를 토대로 여과속도가 낮을수록, 먼지 투입농도가 높을수록, 평균입도가 클수록 집진효율이 높았으며, 여과속도가 높고, 먼지 투입농도가 높을수록 압력손실이 높게 나타났다. 공극 크기가 상대적으로 작은 PTFE 멤브레인이 코팅된 여과백을 사용한 경우, 기존 PTFE 여과백을 사용한 경우에 비하여 집진효율이 높았으며, 표면여과로 포집 분진층 저항계수가 낮아 압력손실이 낮게 나타났다. PTFE 멤브레인이 코팅된 여과백을 사용하여 off-line 탈진을 수행할 경우 on-line 탈진에 비해 적정 여과속도 범위 내에서 PM2.5에 대한 집진효율이 99.99% 이상으로 기존 제작한 여과집진장치를 사용하여 미세먼지를 효과적으로 집진할 수 있었다.

다국어 초록 (Multilingual Abstract)

Health risks and reduced visibility are increasingly growing concerns in East Asia due to the increasing numbers of particulate matter, especially in particle sizes smaller than 2.5 m. There is μ an increase in the amount of research and investment in facilities for air-quality management and particulate-matter control in the affected countries of the region. Baghouses require a fairly high cost of initial investment, but the method is widely used by companies because it is easy to apply on a large scale, its maintenance is easy, and the concentration of emissions can be maintained in a stable manner. If particulate matter can be adequately controlled using the baghouse method, its application would be easy and economical, because existing facilities can be utilized.
Multiple studies have been conducted on the production of filters using fine fabric and on the assessment of the filtration characteristics of polytetrafluoroethylene (PTFE) membrane-coated bag filters implemented on baghouses for the removal of particulate matter.
However, there have only been limited experiments examining the effects of diverse design and operational variables (such as bag-filter material, pulsing type, inlet dust concentration, and filtration velocity in using cylindrical bag filters) on the collection efficiency and the pressure drop across the filter, as well as assessing the prospect of a large-scale system implementation.
In this study, an experimental small-scale baghouse system was developed to assess dust-filtration performance, such as the loss of pressure across the filter heads and ends and the collection efficiency of various designs and operational conditions of the baghouse. The experiment was conducted on silica dusts of various particle sizes emitted during the semiconductor production process, in order to investigate the effects according to dust-particle size. The assessment took into account total suspended particles (TSP), PM10, and PM2.5, the pulsing type (on-line and off-line pulsing) , the cylindrical PTFE type of non-woven fabric filter, and the PTFE membrane-coated fabric filter.
The effects of major operational variables, such as bag-filter material, inlet dust concentration, and filtration velocity were also investigated.
The filtration performance for particulate matter (such as PM2.5) was assessed in diverse experiment conditions and the potential for a commercial application of a large-scale baghouse system for particulate matter filtration was also investigated.

목차 (Table of Contents)

• I. 서 론 ······································································································· 1
• 1. 연구의 개요 ····························································································· 1
• 2. 여과집진장치 ····························································································· 4
• 3. 집진 원리 ·································································································· 6
• 3.1. 관성충돌 (Internal Impaction) ·············································· 7
• 3.2. 직접차단 (Direct Interception) ··········································· 7
• 3.3. 확산 (Brownian Diffusion) ··················································· 7
• 3.4. 정전기력 (Electrical forces) ················································ 8
• 4. 분진 통과 메커니즘 ··············································································· 9
• 5. 여과집진장치 종류 ················································································· 11
• 5.1. 흡인식 (Pull through) ··························································· 11
• 5.2. 압인식(Push through) ··························································· 11
• 6. 탈진방식에 따른 분류 ··········································································· 12
• 6.1. 진동식 (Shaking type) ··························································· 12
• 6.2. 역기류식 (Reverse air type) ················································ 12
• 6.3. 충격기류식 (Pulse air jet type) ·········································· 13
• 7. 간헐식탈진과 연속식탈진 (On-line pulsing and off-line pulsing)
• ····················································································································· 15
• 8. 산업용 여과포의 종류 ··········································································· 15
• 9. 여과포의 수명 단축요인과 대책 ························································· 17
• 10. 집진효율 및 압력손실 식 ····························································· 20
• II. 실험 ········································································································ 21
• 1. 실험장치 ······················································································· 21
• 1.1 공기 및 먼지 공급부 ························································ 22
• 1.2 여과집진장치 본체 ·························································· 24
• 1.3 배출가스 먼지 농도 측정부 ··········································· 24
• 2. 실험용 먼지 ················································································· 25
• 3. 실험 여과포 ················································································· 25
• 4. 실험 방법 ····················································································· 25
• III. 결과 및 고찰 ······················································································· 27
• 1. 예비실험 ······················································································· 27
• 1. 1. 먼지 시료의 입도분포 측정 ········································ 27
• 1. 2. 초기 여과백의 SEM 이미지를 통한 표면관찰 ········ 30
• 2. off-line 탈진 실험 ······································································· 32
• 2. 1. 먼지농도변화에 따른 집진효율 ·································· 32
• 2. 2. 먼지농도변화에 따른 압력손실 ·································· 37
• 2. 3. 여과속도변화에 따른 집진효율 ·································· 39
• 2. 4. 여과속도변화에 따른 압력손실 ·································· 44
• 3. on-line 탈진 실험 ······································································· 46
• 3. 1. 여과속도변화에 따른 집진효율 ································· 46
• 3. 2. 여과속도변화에 따른 압력손실 ································· 51
• 4. 저항계수 ······················································································· 53
• 4. 1. 여과백 자체의 저항계수 (k1) ······································ 53
• 4. 2. 포집먼지층의 저항계수 (k2) ······································ 55
• 5. 여과집진 완료된 여과백의 SEM 이미지를 이용한 표면관찰
• ········································································································ 57
• IV. 결 론 ···································································································· 59
• V. 참고문헌 ································································································ 60
• Abstract ····································································································· 64