산업용 LNG 보일러실의 폭발위험장소 설정방안

다국어 초록 (Multilingual Abstract)

Recently, there have been frequent domestic small and large accidents by explosions in petrochemical industry and at home and businesses using gases, causing extensive damage to properties and loss of life. Accidents by explosion, leading to big gas explosion or fire, are of increased social concerns. City gas, flammable gas, is a material that forms explosive atmosphere and causes explosion when released. It is used as fuel for boiler or heating furnace in the industrial world, and in the course of replacing diesel fuel used in the past. Electric machines and appliances installed inside a boiler room using city gas, subject to occupation safety and health acts, should be maintained by establishing explosion hazardous area and preparing classification map.
Accordingly, through case studies based on KS C IEC 60079-10-1 and IP15, the extent of zone can be accurately determined by performing calculation process for explosion hazardous area classification. Electric facilities related to boiler should be installed explosion proof appropriate for the classification after establishing explosion hazardous area in accordance with standards set by occupation safety and health acts. Especially, it is desirable to apply reasonable explosion hazardous area calculation method due to routine excessive design of city gas facilities.
It is concluded that it can be zoned as explosion non-hazardous area because the extent of zone, in establishing explosion hazardous area, was confined at less than 0.1m based on accident impact assessment using KS C IEC 60079-10-1 as a calculation formula, with less than 0.1m hypothetic volume.
In industries requiring constant use of boiler steam, such as display and semiconductor process, boiler operation must be ceased when attempting to enhance facilities with general electric machines and appliances to those with explosion proof, within the extent of zone with explosion risk of LNG boiler room. In case of such interruption, extensive production damage is expected. In this study, we presented how to make enhancements using enclosed local exhaust while operating boiler.
In establishing explosion hazardous area, KS C IEC 60079-10-1 has priority for application. If unable or insufficient to apply this, it is presumed that standards of other countries or organization cannot be utilized as normative references. We concluded that explosion hazardous area can be reasonable established without difficulties of setting release hole size at field if suggested values by both KS C IEC 60079-10-1 and IP15 are used.

목차 (Table of Contents)

• Ⅰ. 서 론 1
• 1. 연구배경 및 목적 1
• 2. 연구동향 3
• Ⅱ. 위험장소 설정 방법 4
• 1. 폭발위험장소 설계 흐름도 4
• 2. 국내 방폭관련 기술기준 5
• 2.1 산업안전보건법 관계법 5
• 2.2 한국산업표준 6
• 2.3 KOSHA Guide P-110-2012 6
• 3. 국제 방폭관련 기술기준 7
• 3.1 IP15 7
• 3.2 API 505 8
• 3.3 NFPA 497 8
• 4. 폭발위험장소 구분절차 10
• 4.1 폭발위험장소 10
• 4.2 비폭발위험장소 11
• 4.3 폭발위험장소의 설정 11
• 4.4 폭발하한 11
• 4.5 환기등급 11
• 5. 폭발위험장소 계산방법 16
• 5.1 임계압력 16
• 5.2 초크상태 가스의 누출속도 16
• 5.3 초크속도 아닌 가스의 누출속도 17
• 5.4 가상체적 Vz와 폭발위험장소 크기와의 관계 17
• Ⅲ. 폭발위험장소의 설계 19
• 1. 산업용 보일러실의 누출시나리오 19
• 2. 국내기준에 의한 설계 20
• 2.1 폭발위험범위 20
• 2.2 전체환기의 산정 22
• 3. 국제기준에 의한 설계 24
• 3.1 전체환기의 산정 29
• 3.2 국소배기의 산정 31
• Ⅳ. 위험성 평가 33
• 1. 누출모델링 33
• 2. 폭발위험범위 위험성 검토 33
• 2.1 사례 1 : 공급압력 0.074 MPa, 체적 6.4 ㎥ 35
• 2.2 사례 2 : 공급압력 0.088 MPa, 체적 4.2 ㎥ 35
• 2.3 사례 3 : 공급압력 0.044 MPa, 체적 7.6 ㎥ 36
• 2.4 사례분석 결과 42
• Ⅴ. 결 론 43
• 참고문헌 44
• 국문요약 46