Large Room Fire cont'd

DOE-HDBK-3010-94

7.0 Application Examples; Liquid Storage and Ion Exchange Examples

The total energy required to boil all of the solution in one tank is 1E+8 calories.

NUREG-1320 gives simple correlations for heat generated by wood and kerosine fires

from which estimates of the amount of wood and kerosine that would produce 1E+8

calories can be made. Barring extreme configurations, assuming that one-tenth of the

energy liberated by the burning material is absorbed by the liquid in the tanks is

conservative. This assumption will be used to estimate the range of fuel quantities

needed to completely vaporize the liquid.

The amount of material needed can be determined by the rearranged equation:

Mb = Qa / (Xa * Ht)

(7-6)

where:

Mb = fuel burned (g),

Qa = actual heat released (calories),

Xa = theoretical heat release efficiency, and

Ht = fuel heat of combustion (cal/g).

The general heat of combustion of wood is 4300 cal/g, and the actual heat release is

70% of the theoretical value. Designating Qa as 1E+8 calories yields 33,000 g of

wood. It is doubtful that large accumulations of hardwood, such as oak or mahogany,

would be present, so a typical density of 450 kg/m3 for cheaper wood is assigned.

Taking into account the factor of 10 previously mentioned, the amount of wood fuel

necessary to evaporate a precipitator feed tank is between 0.07 and 0.7 m3 (2.5 to 25

ft3). A linear relationship can be assumed for quantities of fuel necessary to

evaporate less than the entire tank contents.

The general heat of combustion of kerosine is 11,000 cal/g, and the actual heat

release is 91% of the theoretical value. These values yield 10,000 g of kerosine. At

a general specific gravity of 0.75, this value corresponds to 13 l. Taking into account

the factor of 10 previously discussed, the fuel range estimated is 13 to 130 l (3.4 to

34 gal.) of kerosine.

All of the plutonium storage tanks (i.e., no waste tanks) together, hold 1780 l. To

boil all of this material would require 1.5E+9 calories. The fuel requirements for

such a fire would be 1.1 to 11 m3 of wood (40 to 400 ft3) or 200 to 2000 l of kerosine

(50 to 500 gal.). These numbers may seem ludicrous on initial examination.

However, for the sake of example, assume the tank farm structure walls are made of

Benelex for shielding purposes because the process had significant Americium

contamination. The walls would be approximately 7.5 m and 4.2 m wide, and 3.3 m

tall. If the walls were only 0.15 m thick (0.5"), the total volume of pressed wood

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