Formation Damage, Stimulation and Artificial Lift - Petroleum Production Operations - Petroleum Engineering Previous Year Questions

A well in a very large reservoir has a wellbore radius of 10 cm. The sandstone, with a porosity of 0.25 and 12% (by grain volume) calcite (\( \text{CaCO}_3 \)), is to be acidized with a preflush (HCl solution) so as to dissolve all the calcite up to a distance of 1 m from the wellbore. 1 \( \text{m}^3 \) of preflush is able to dissolve 0.082 \( \text{m}^3 \) \( \text{CaCO}_3 \). Assume that the reaction between HCl and \( \text{CaCO}_3 \) is instantaneous.
The minimum preflush volume required per meter of the formation thickness is __________ \( \text{m}^3 \). (rounded-off to two decimal places)

For the abrasive jet machining process, the ratio of abrasive volume to carrier gas volume is 0.25. Further, the ratio of abrasive density to carrier gas density is 25. The mass ratio of abrasive to the mixture of abrasive and carrier gas is _____ (round off to 2 decimal places)

Q.No. 48 Well stimulation is carried out in a homogeneous formation. The well is stimulated up to a radial distance of 54 inch from the surface of the wellbore. The diameter of the wellbore is 12 inch. The permeability enhancement in the stimulated region is found to be 10 times that of the unstimulated region. Assuming steady-state radial flow, the skin factor after stimulation (rounded off to two decimal places) is ______.

Which of the following has the most proppant carrying capacity during hydraulic fracturing process?

Which of the following improve(s) the productivity index of a vertical well in an oil reservoir?

The sectional view of three different damaged regions (marked as P, Q and R) near the vicinity of a perforation is shown in the figure.
Choose the correct option by matching the entries in GROUP X with corresponding terms in GROUP Y.

GROUP X	GROUP Y
P	(I) Grain fracturing
Q	(II) Charge and core debris
R	(III) Compacted pulverized zone