| Summary: | 碩士 === 國立交通大學 === 工學院產業安全與防災學程 === 99 === In view of the fact that all of the current 12-inch semiconductor plants have exploited limited land space for the installing of precise and sophisticated equipments, and they have made extensively use of combustible and inflammable liquids (such as IPA, photo-resistant liquid, and others) and special gases (such as SiH4, H2, and so on). Therefore, the fire loading and investment cost per unit area is relatively high. This thesis mainly investigates various kinds of safety designs based on domestic legal provisions and standards within the scope of explosion-proof division, with the assistance of the software ALOHA (areal locations of hazardous atmospheres) for consequence simulation analysis for the influencing region due to fire explosion. During different seasons, it was found from the ALOHA consequence simulation analysis with different wind speeds that when the wind speed was greater, it could further help increase the speed for air dilution, and so hazard of toxic gas and explosion hazard was lowered. However, heat radiation was enhanced with increasing wind speed.
The simulation assumed the scenario that 12000L storage tank for isopropyl alcohol (IPA) unfortunately leaked, the concentration of its inflammable vapor did not reach the explosion level. Nonetheless, if the tank fire continued to burn, the influence of heat radiation within 10m region won’t result in the hazard of immediate death.
However, if boiling liquid expansion vapor explosion (BLEVE) occurred, it would create devastative influence on the entire plant and neighboring manufacturing plants, with its scope region reaching 101-107 m. For the operation of a 12kg steel-bottle of silane, if instantaneous and complete leakage occurred or continuous gas leakage was found from its pipeline, 0.7 psi of impact with overpressure explosion would occur within a region of 13-15 m to leakage source. Therefore, all kinds of fire operation must be prohibited and explore-proof electrical equipment must be effectively used within the control range of 85-90 m.
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