$(20$ points$)$ Butane liquid is stored in a large vertical insulated tank. A refrigeration unit

maintains the temperature of the liquid butane at $28F.$ The tank is pressurized with nitrogen

to atmospheric pressure. A $14-$inch $($actual$)$ inside diameter pipe located at the bottom of the

tank is used to remove or add butane to the tank. You have been asked to analyze the

incident of separation of the $14-$inch pipe from the bottom of the tank. The plant is interested

only in the realistic release incident, not the worst$-$case incident.

a$.$ Use table $4-6$ in the textbook or the table provided in the lecture to determine the release

area for the $14-$inch pipe for this realistic release incident. What hole diameter is this

equivalent to$?$

b$.$ If the maximum height of the butane liquid in the tank is $75$ feet, what is the discharge

rate, in $ga\frac{l}{sec},$ thru this hole when the hole first forms?

The density of the butane at these conditions is $37\mathrm{.}5lb\frac{m}{f}t3$ and its molecular weight is

$58\mathrm{.}123.$

$(20$ points$)$ The discharged butane liquid from part $1$ is collected in a pool in an open

impoundment area. The evaporation rate of the butane in this pool is estimated from

Equation $4-106$ in the text as $1$ gallon per minute. If the outdoor local ventilation rate is $3000$

$f\frac{t^3}{m}in,$ what is the concentration $($in volume percent butane$)$ of the butane in the vicinity of

the pool? The ambient temperature is $77F.$