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Assume that the ideal gas law applies. Then the partial pressures are calculated using the mole fractions. Solution The solution involves determining the number of moles of nitrogen in the tank at the final given temperature and pressure T 2 and p2 , and at the initial conditions, and subtracting. Further down the line, after mixing is complete, the gas is found to contain How many m3 of the initial gas were flowing per minute through the pipe? Solution The problem is similar to other nonreacting material balance problems.
It is convenient to imagine the pipeline between the point of injection of air to the point of sampling as a mixer.
The process may be considered to be a steady state process without reaction. All flow rates can be then be converted to the basis of 1 minute at the end of the problem. However, it is easier to use the given flow rate in m3 assuming that the temperature and pressure are the same for all streams so that moles are proportional to m3 in each stream.
The unknowns are: F, P, xCl2 , and xN2 or n 1 and n3. Solution The problem is just a material balance problem with volumes of inlet and outlet gases specified instead of moles.
We could select ft3 or moles as a basis. Steps 1, 2, 3, and 4 This is a steady state problem with reaction. Keep the same basis.
The water and carbon dioxide are the same as in part b, and there is no O2 in the flue gas. Assume all the acid used completely reacts. Solution Steps 1, 2, 3, and 4 You first must determine the number of moles of hydrogen produced, and then calculate the acid required via stoichiometry.
This is a steady state process with reaction except for the Zn which can be assumed to exit the vessel. Zn mass fr. MW g mol mol fr. The only unknown we want to solve , xH 4 2O Zn for is F. The easiest balance to make to get F is an H2SO4 compound balance, but other reasonable balances can be used.
In Out Generation Consumption Accum. Hollows fibers made of polymeric membrane fill the separations unit. The waste gas containing 1. To meet the product gas specifications, part of the product stream has to be recycled to reduce the concentration of SO2 entering the separator itself to 1.
Solution Steps 1, 2, 3, and 4 This is a steady state process with reaction and recycle. All the known data have been placed in the figure. No reaction occurs. Then G, P, W, and R are unknowns and their compositions are known. Since the temperature and pressure are constant throughout, volume balances can be used mole fraction is the same as volume fraction.
The balances could be made in moles and then converted to the basis of m3. Steps 7, 8, and 9 The system is the overall process. Membrane modules can be tubular, spiral-wound, or plate and frame configurations. Membrane materials are usually proprietary plastic films, ceramic or metal tubes, or gels with hole size, thickness, chemical properties, ion potential, and so on appropriate for the separation.
Examples of the kinds of separation that can be accomplished are separation of one gas from a gas mixture, separation of proteins from a solution, dialysis of blood of patients with kidney disease, and separation of electrolytes from non electrolytes. Problem 4. Solution This is a steady state problem with reaction and recycle. Make the system the reactor plus the separator to avoid having to calculate information about the converter outlet stream. Use an SO2 balance in kg mol.
In Out Gen. Calculate the pressure in atmospheres in the cylinder a assuming N 2 to be an ideal gas b assuming the pressure of N2 can be predicted by van der Waal's equation c using the compressibility factor method d using the Redlich-Kwong equation of state. Some approximation may be required.
It is desired to store Calculate the pressure inside the cylinder by a assuming that the mixture obeys the ideal gas laws; b using the compressibility factor determined by the pseudo critical point method. Solution Basis: Also estimate the normal boiling point of benzene the vapor pressure at 1 atm , and compare it with the experimental value taken from a handbook. At the boiling point the vapor pressure is 1 atm mmHg abs. The two values agree well. The vapor pressure of ethyl acetate is mmHg abs.
By using the chart estimate the a. Compare with the experimental value of First, select a logarithmic vertical scale and place even values of the vapor pressure on the vertical scale to cover the desired pressure range. Then draw a straight line representing the vapor pressure of water at any suitable angle so that you cover the range of temperatures and pressures needed for the problem.
To locate each integer value of the water temperature such as 30, 50, , etc. Then drop vertically down to the temperature axis and mark the axis with the selected temperature the spacing will not be at even intervals. Repeat to get a series of temperatures. Finally, put the two points given for ethyl acetate on the chart and draw a line between them for ethyl acetate. The temperature and volume of the vessel remain constant. What is the volume of dry gas under standard conditions?
How many grams of water vapor are present in the gas? Solution Sat. At the initial conditions the total pressure is the sum of gas pressure and vapor pressure of the water.
The first step in the solution involves determining the pressure of the dry gas assuming constant temperature and volume. Is there adequate air for complete combustion of all the toluene? If so, determine the percent excess air present for combustion. At saturation — What is the dew point temperature of the mixture if it is at 85 psia?
What is the bubble point temperature of the mixture if it is at 70 psig? The barometer reads mmHg. Solution a. The dew point temperature is the temperature at which the vapor first condenses when the vapor and liquid are in equilibrium. The bubble point temperature at a given pressure is the temperature at which the liquid mixture vapor pressure equals the total pressure.
The mixture is assumed to be all liquid and the vapor composition is assumed to be in equilibrium with the liquid. If it were cooled, what would be the composition of the liquid that first condenses out of the gas? Solution Basis: 1. Assume ideal vapor and liquid at the dew point. If not, repeat to bracket the value 1. Calculate the: a. Calculate: a.
The dew point of the gas can be determined from the steam tables. What percentage of the water originally in the air was removed during the processing? Solution This problem can be treated as a steady state problem without reaction, or as an unsteady state problem.
We will carry out the solution as a steady state problem. Recall that the water vapor condenses on compression so that the compressed gas is still saturated. Two unknowns exist: W and P. Total balance lb mol 1. Some axial flow compressors have adjustable guide vanes such as occur in units for natural gas liquification. A minimum flow exists below which the compressor operation becomes unstable surges and back flow can occur as well as mechanical damage.
Solucionario-Principios Elementales de los Procesos Quimicos - Felder -
solucionario-principios elementales de los procesos quimicos - felder -
Elementos De Ingeniería De Las Reacciones Químicas - S. Fogler - 4ta Edición