List of top Petroleum Engineering Questions on Petroleum asked in GATE PE

A shell-and-tube heat exchanger is used for cooling crude oil from $400~\text{K}$ to $360~\text{K}$. Crude oil flows through the tube at $3650~\text{kg/h}$. Water enters the shell side at $310~\text{K}$ and has a flow rate of $1600~\text{kg/h}$. Assume $c_{p,\text{oil}}=2.5~\text{kJ/(kg.K)}$, $c_{p,\text{w}}=4.187~\text{kJ/(kg.K)}$, overall $U=300~\text{W/(m}^2\!\cdot\!\text{K)}$, and countercurrent flow. The required heat–transfer area is ............... m$^2$ (rounded to one decimal place).

An oil droplet is to be mobilized by injecting water through a pore throat. The oil–water interface has the rear radius of curvature $r_A = 25\times10^{-6}\ \text{m}$ and the forward radius of curvature $r_B = 5\times10^{-6}\ \text{m}$. The pore is completely water-wet (contact angle $=0^\circ$) and interfacial tension is $\sigma = 0.025\ \text{N/m}$. The minimum pressure drop required to mobilize the trapped oil droplet is ________ N/m$^2$ (nearest integer).

Crude oil having density and viscosity of $850\ \text{kg/m}^3$ and $2\times10^{-3}\ \text{Pa}\!\cdot\!\text{s}$, respectively, is flowing at an average velocity of $0.35\ \text{m/s}$ through a horizontal capillary tube. The inside diameter and length of the capillary tube are $2.5\times10^{-3}\ \text{m}$ and $0.30\ \text{m}$, respectively. The Fanning friction factor is $f=\dfrac{16}{\mathrm{Re}}$. The pressure drop across the capillary tube is ________ Pa (rounded to one decimal place).

A non-Newtonian drilling fluid (Bingham plastic) is between two flat parallel rectangular plates of area $10\ \mathrm{cm^2}$ each, separated by $1\ \mathrm{cm}$. A force of $300$ dyne is required to initiate motion of the upper plate. A force of $600$ dyne keeps the plate moving at a constant velocity of $10\ \mathrm{cm/s}$. The constitutive law is \[ \tau_{yx} = \mu_p \dot{\gamma} + \tau^o_{yx}. \] Find the Bingham plastic viscosity $\mu_p$ in dyne$\cdot$s/cm$^2$ (rounded to the nearest integer).

Consider a micellar displacement process in a homogeneous reservoir with a porosity of 30%. The volume of the microemulsion slug to be injected is 4% of the pore volume. The slug contains 4 vol% surfactant. The density of the rock and the surfactant is $2.7~\text{g/cm}^3$ and $1.1~\text{g/cm}^3$, respectively.

Assuming that the average surfactant adsorption is 0.25 mg/g of the reservoir rock, the fraction of the injected surfactant that will be adsorbed is ............. (rounded to two decimal places).

A compressional acoustic wave takes $55~\mu s$ to travel $0.3048~\text{m}$ through a rock formation having bulk modulus of $37.5~\text{GPa}$ and shear modulus of $31~\text{GPa}$. The bulk density of the rock is ............. kg/m$^{3}$ (rounded to two decimal places).

Consider 1D oil--water flow with $k_{ro}^o=1,\ k_{rw}^o=0.2,\ S_{wr}=0.2,\ S_{or}=0.4$. Oil and water viscosities are $5$ cP and $1$ cP. With \[ k_{ro}=k_{ro}^o(1-S_w^*),\quad k_{rw}=k_{rw}^o(S_w^*),\quad S_w^*=\frac{S_w-S_{wr}}{1-S_{or}-S_{wr}}, \] the total relative mobility at $S_w=0.4$ is _________ cP$^{-1}$ (rounded to one decimal place).

Match the entries between Group-I and Group-II for seismic data acquisition, processing and interpretation.

Schematic of phase diagrams for a pure gas hydrate system of methane (CH$_4$), carbon dioxide (CO$_2$), hydrogen sulphide (H$_2$S) and nitrogen (N$_2$) between the lower and upper quadruple points are shown in the figure. Arrowheads indicate the stable hydrate region for a particular gas hydrate system. Match the phase diagram with the corresponding pure gas hydrate.

The figure shows a schematic representation of the organic solid phase diagram for wax, hydrate, and asphaltene deposition around the bubble point of a sample reservoir fluid. Arrowheads indicate the stable region for a corresponding organic solid. Match the phase diagram with organic solids.

Consider the following accident scenario: Failure of a drain connection on a rich oil line at the base of an absorber tower in a gas producing plant allowed the release of rich oil and gas. The resulting vapor cloud ignited from the ignition system of an engine-driven recompressor. The absorber tower eventually collapsed across a pipe rack. The breakage of the pipelines added more fuel to the fire and led to the total destruction of the plant. The resulting fire burnt for 3 days.

Kerogen is an intermediate compound in the process of petroleum formation in a sedimentary basin. This is typically classified into four categories (Type-I, Type-II, Type-III and Type-IV) based on the relative amount of carbon (C), hydrogen (H), oxygen (O) present in it (shown in the figure below). Which of the following is the X-axis and Y-axis, respectively?

Consider an ideal liquid–vapor mixture at equilibrium having liquid phase mole fraction $(x_i)$ and gas phase mole fraction $(y_i)$ of component $i$. If at a given temperature, $P_{v_i}$ is the vapor pressure of pure component $i$ and $P$ is the total pressure, then the equilibrium ratio $(k_i)$ is

A switch-over event in a producing well occasionally results in a reportable oil leak. An analysis of the data shows that the chance of a reportable leak is 1 in 500 switch-over events. It is observed that 10 switch-over events occur every day. If the occurrence of a reportable leak follows a Poisson distribution, the number of days in a year (of 365 days) with no reportable oil leaks from switch-over events is ............. (rounded to nearest integer).

A binary mixture of n-butane ($C_4H_{10}$) and n-pentane ($C_5H_{12}$) is under thermodynamic equilibrium at 180°F and 95 psia. The vapor pressures of pure C4H10 and pure C5H12 at 180°F are 160 psia and 54 psia, respectively. Assuming ideal solution behavior (i.e., Raoult's law and Dalton’s law are valid), the mole fraction of the n-butane in the gas phase is ............. (rounded to three decimal places).

A highly permeable reservoir with initial reservoir pressure of 3000 psi is under active water drive from a surrounding large aquifer. The final stabilized reservoir pressure is 2500 psi. Following data associated with the reservoir at 2500 psi are given.
Oil production rate = 30,000 STB/day
Water production rate = 0 STB/day
Oil formation volume factor, $B_o = 1.5 \, \text{bbl/STB}$
Gas formation volume factor, $B_g = 0.00070 \, \text{bbl/scf}$
Water formation volume factor, $B_w = 1 \, \text{bbl/STB}$
Producing Gas to Oil Ratio, GOR = 850 scf/STB
Gas solubility, $R_s = 700 \, \text{scf/STB}$ If the reservoir pressure and the reservoir production rates remain constant, the water influx rate is ............. bbl/day (rounded to nearest integer).

A volumetric undersaturated solution gas drive reservoir (without gas cap, no water influx, and with no initial gas saturation) has an initial water saturation of $15%$ which remains unchanged during production. After the production of $10%$ of the initial oil (measured at surface conditions), the oil formation volume factor $B_o$ is reduced from its initial value of $1.4~\text{bbl/STB$ to $1.2~\text{bbl/STB}$. The final gas saturation in percentage is _________ (rounded to one decimal place).}

Select the statement(s) that is/are TRUE.

A centrifugal pump running at 500 rpm delivers 60 liters/minute with a head of 50 m. At the same efficiency, if the rotational speed is increased to 1000 rpm, the discharge rate and head would respectively be:

Which is/are the thermodynamic inhibitor(s) for natural gas hydrate?

Which of the following hydrocarbon trap(s) is/are a result of sedimentary facies changes?

Which of the following relations defines the coefficient of isothermal compressibility ($C_g$) for a gas? Here, $p$, $T$, and $v$ represent the pressure, temperature and volume of the gas, respectively.

In-situ combustion method for enhanced oil recovery is commonly used for

A mixture of a flammable gas and air can ignite ONLY if

Which of the following is a sedimentary rock?