The effect of pressure on various properties of black oil is shown in the figure. The bubble point pressure is \(P_b\).
Which of the following option(s) is/are CORRECT?
The effect of pressure on various properties of black oil is shown in the figure. The bubble point pressure is \(P_b\).
Which of the following option(s) is/are CORRECT?
Show Hint
- Curve 1 represents solution gas-oil ratio.
- Curve 2 represents oil viscosity.
- Curve 3 represents oil formation volume factor.
- Curve 3 represents oil density.
The Correct Option is A, B, C
Solution and Explanation
Step 1: Identify Curve 1.
- The solution gas-oil ratio (\(R_s\)) increases with pressure until bubble point pressure \(P_b\).
- Beyond \(P_b\), oil is saturated, and no more gas dissolves. Thus, \(R_s\) remains constant for \(P > P_b\).
- This matches the behavior of Curve 1.
Step 2: Identify Curve 2.
- The oil viscosity decreases with increasing pressure below \(P_b\) because gas goes into solution.
- At \(P_b\), viscosity is minimum. Beyond \(P_b\), viscosity increases with pressure due to compression.
- This behavior matches Curve 2.
Step 3: Identify Curve 3.
- The oil formation volume factor (\(B_o\)) increases as more gas dissolves in oil, reaching a maximum near \(P_b\).
- Beyond \(P_b\), oil becomes slightly compressible, so \(B_o\) decreases with pressure.
- This matches Curve 3.
Step 4: Oil density check.
- Oil density does not match Curve 3's behavior. Density generally increases monotonically with pressure.
- Hence, option (D) is incorrect.
Final Answer: \[ \boxed{\text{(A), (B), and (C)}} \]
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