A productivity test conducted on a crude oil well indicates a stabilized flow rate of 150 STB/day (water-free oil production) at a bottom-hole flowing pressure of 935 psig. After shutting the well for 24 hours, the bottom-hole pressure reached a static value of 1250 psig. The Absolute Open Flow (AOF) potential of the well is \(\underline{\hspace{2cm}}\) STB/day.
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Correct Answer: 580
Solution and Explanation
\[ AOF = \frac{q_0}{\left( \frac{P_{static} - P_{bhf}}{P_{bhf}} \right)} \] where \( q_0 = 150 \, \text{STB/day} \), \( P_{bhf} = 935 \, \text{psig} \), and \( P_{static} = 1250 \, \text{psig} \). Substitute the values into the equation:
\[ AOF = \frac{150}{\left( \frac{1250 - 935}{935} \right)} = \frac{150}{\left( \frac{315}{935} \right)} = \frac{150}{0.3375} \approx 444.44 \, \text{STB/day} \] Thus, the AOF potential of the well is \( \boxed{444.44} \, \text{STB/day} \).
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