hello,everybody,
How to calculate the fire water consumption in process units in gas&oil plant?
anybody has the handbook of calculation?
normally,the worse case will happen in the crude oil tank farm,the fire water consumption of fixed roof crude oil tanks for exposure protection shall be according to API 2030,4.1L/m2/min for min. 6 hours.
but, how to calculate the fire water consumption in process units?according to NFPA 15,the application rate of fire water for exposure protection for process units shall be 4.1~20.4L/min/m2, but how to group the equipments? if group each process unit together,the total fire water consumption will be very large,the water consumption may be 5 times of that used in tank farms, how to group the equipments(like 3 phase separators and desalters etc.)is a problem.and in NFPA codes,there are not very clear definition of it.
for storage tanks,if the space(shell to shell) between the fired tank and adjacent tanks is bigger than one time diameter,then the adjacent tanks may not be cooled.so the fire water consumption will be lowed down.
but for the process units,which is the space requirements?I have not gotten it from the NFPA codes,if all of the equipments need to be cooled, the fire water consumption may be very big.I don't want to cool all the equipments at the same time.