Benzene is to be absorbed from coal gas by means of a wash-oil. The inlet gas contains 3 per cent by volume of benzene, and the exit gas should not contain more than 0.02 per cent benzene by volume. The suggested oil circulation rate is 480 kg oil/100 m³ of inlet gas measured at 273 K and 101.3 kN/m². The wash oil enters the tower solute-free. If the overall height of a transfer unit based on the gas phase is 1.4 m, determine the minimum height of the tower which is required to carry out the absorption. The equilibrium data are: Benzene in oil (per cent by mass) Equilibrium partial pressure of benzene in gas (kN/m²) 0.05 0.013 0.01 0.033 0.50 0.20 1.0 0.53 2.0 1.33 3.0 3.33

Back HW#2 QUESTION1/60pts] A fluid of viscosity u flows in the horizontal cylinder (radius R) shown in the figure under a constant pressure gradient dP/dx. The inner core of the cylinder is filled with a porous material. The flow in this porous region is slow and assumed to be a plug-type flow such that the velocity is constant and everywhere the same inside the porous region. Denote this velocity by Uo. The flow in the open (non-porous) region is steady, Newtonian, incompressible and axisymmetric. It will be assumed that only the axial (x) component of the velocity is non-zero. Flow Open flow T&R Porous media flow R N.B. All your answers must be expressed in terms of µ, U₁, a, R and dP/dx. (a) Use the continuity and Navier-Stokes equations to determine the expression of the velocity in the open region. (b) What is the expression of the average velocity in the open region? (c) Is the assumption of a linear velocity profile in the open region acceptable when this region Tuatifi 1:

the pressure drop across the tube bank, and (c) the rate of condensation of steam inside the tubes. Evaluate the air properties at an assumed mean temperature of 35°C and 1 atm. Is this a good assumption?solve this part too

Which of the following statements about an oil’s viscosity is not true? a. The ability of oil to resist flow is its viscosity. b. Viscosity is affected by temperature; hot oil flows faster than cold oil. Oil flow is important to the life of an engine. c. In the API system of oil viscosity classification, the lighter oils receive a higher number. d. Heavyweight oils are best suited for use in high-temperature regions. Low-weight oils work best in low temperature operations.