Research On Fire Accident Simulation And Fire Safety Distance Of Large Floating Tank

Compared with current fire safety distance laws and regulations of large floating tank at home and abroad,the fire safety distance standards of large floating tank in our country is insufficient to meet the safety requirement of the adjacent oil tanks in the fire environment.Full surface fire for its serious disastrous consequence as the most dangerous fire scenarios.It is very likely to cause a boiling over accident,resulting in the fire accident of group tanks or even the destruction of the whole oil depot once it happens.It is necessary to work out reasonable and effective fire safety distance to minimize the influence of tank fire on adjacent tanks and prevent the spread of disaster.One hundred thousand cubic meters tank full surface fire accidents in the safety distance of 0.3D,0.4D,0.5D and 0.6D are performed using fire dynamic simulator(FDS).The heat radiation flux on the wall and top of neighboring tank under different wind speeds and temperature are analyzed.The results shows that wind speed has a greater contribution on the behavior of tank fire than temperature.The heat radiation flux calculated from FDS simulation is compared with the theoretical calculation value.The results show that the difference between simulated value and theoretical value is small,and simulation model is reasonable.The environmental parameters which affecting the fire combustion characteristics in Zhenhai,Zhoushan,Huangdao,Dalian,Dushanzi,Lanzhou and Tianjin national petroleum reserve base are analyzed in the last 5 years.The full surface fire accidents of one hundred thousand cubic meters floating tank under 0.4D fire safety distance are simulated under the environmental conditions of the annual average wind speed,maximum wind speed,maximum temperature and minimum temperature.Combined with the Domino effect probability model and the risk acceptance criteria of adjacent tank fire,the thermal radiation damage of adjacent tank is analyzed.The results show that the current 0.4D fire prevention distance can meet the safety requirement of the National Oil Reserve Bank of Zhenhai,Zhoushan,Dushanzi,Lanzhou and Tianjin National Petroleum Reserve Bank.The theoretical model of thermal radiation and FDS simulation are used to modify the fire safety distance for Huangdao and Dalian National Petroleum Reserve Bank which are not satisfied with tank safety requirement.The safety distance of one hundred thousand cubic meters floating tanks should increase to 0.64 D and 0.55 D respectively.