Chemical Process Calculations Homework Help

P4.36 100 gmol/min of a solution of 70 mol % ethanol/30 mol % water is fed to a reactor operating at steady state, along with 80 gmol/min of air (79 mol % N₂, 21 mol % O₂). Ethanol (C₂H5OH) reacts with oxygen to make acetaldehyde (CH,CHO). Acetaldehyde is further oxidized to acetic acid (CH₂COOH). Write the two stoichiometrically balanced chemical equations. What is the byproduct of the reactions? What is the limiting reactant? If there is 100% conversion of the limiting reactant and the production rate of acetaldehyde is 25 gmol/min, calculate the fractional conversion of the excess reactant, the yield of acetaldehyde from ethanol, and the composition and flow rate of the reactor effluent stream.

3. (5 Points) An aqueous brine solution at a flow rate of 150.0 kg/min is fed to a continuous desalination process in which half of the water in the 2.00 wt% NaCl feed stream is evaporated and recovered as pure liquid water by cooling. Draw and label a flow diagram of the process and define the basis.

A second-order process has the transfer function g_{p}(s)=\frac{3}{s(2 s+1)} A) Find the output as a function of time, for a unit step input change. (7 points) B) Sketch the expected behavior and comment on the system stability. (3 points)

Problems from Chapter 1, textbook:1.11 Use a reaction rate of K=0.35/day(instead of K=0.25/day)(Materials Balance, CSTR, 1st Order) a) 10.21 mg/L b) 8.21 mg/L c) 5.24 mg/L d) 6.4 mg/L

2. the following transfer function governs the rate at which liquid water is boiled off in a boiler, 6 [kg/s], to the pressure of natural gas p [bar] in the supply line that feeds the furnace. G(s):=\frac{B^{*}(s)}{P^{*}(s)}=\frac{200}{3 s+1} an engineer accidentally opened a valve upstream of the process (and quickly closed it after realizing the mistake), causing an under damped oscillation input in the natural gas supply pressure, p*(t) = 1/10 -T sin(2t). \text { write the Laplace transform of the input } P^{*}(s):=\mathcal{L}\left[p^{*}(t)\right] \text {. } \text { write the Laplace transform of the output } B^{*}(s):=\mathcal{L}\left[b^{*}(t)\right] \text {. } ) (2 points) posit a partial fraction expansion of B*(s) in preparation for inverting it to the time domain. (d) (3 points) determine the coefficients in your partial fraction expansion. (e) (3 points) finally, write an expression for the response b*(t) (in the time domain).make sure that your expression is real (i.e. does not contain imaginary numbers).

3. In a shell-and-tube heat exchanger under design condition, the cooling water gets heated from 30°C to 45°C while the process stream is cooled from 100°C to 60°C. Due to fouling only in the process side, the mass flowrate of water has to be increased to 160% of the design flow to maintain the process side outlet temperature at its design value with the same design flowrate of the process stream. Express the fouling heat transfer coefficient (hr.), which is the inverse of the fouling heat transfer resistance, as a multiple of process side heat transfer coefficient (ho). Assume that under design condition, there is no fouling. Also assume that all the resistance to heat transfer is on the process side.

A house has a composite wall of wood, fiberglass insulation, and plaster board, as indicated in the sketch. On a cold winter day, the convection heat transfer coefficients are ho60 W/m² K and h; = 30 W/m² K. The total wall surface area is 350 m². **Given: Fiberglass blanket: k, = 0.038 W/m.K Plywood siding: k, = 0.12 W/m K Plasterboard: kp = 0.17 W/m.K (a) Sketch the thermal circuit for the system. Label heat flow (W) direction,all temperatures, label all resistances. Write expression for all resistances. (b) Determine the total heat loss through the wall.

1. The figure below shows a schematic description of a dilution process using a mixer. The mixing tank operates at a constant temperature and its content is assumed to be well-mixed. The holdup volume of the mixer is V. Stream A is fed at a flowrate of Fo and composition Co to the mixer. Water is fed at a flowrate of Fi to dilute the composition of stream A to a final composition CA in the outlet stream that is flowing at F2. Assuming all streams are incompressible and have the same density, a) Develop expressions for the dynamic (un-steady state) condition of the process. b) Develop an expression for the steady state composition of the outlet. c) Determine the degrees of freedom to control the final composition of the outlet.

7) 5 points. Reactants plus solvent enter an adiabatic reactor at 300 K. If the reactants react completely the outlet temperature is 700 K. However, for safety reasons, the outlet temperature must be kept below 500 K. Which of the following steps can reduce the outlet temperature but still allow complete conversion? A. Decrease the amount of solvent fed B. Use a solvent with a lower heat capacity C. Use a stoichiometric excess of one of the reactants D. All of these E. None of these

5) 10 points. In a steel plant, a 25g block of iron at 175°C is dropped into 1 L of water at 20°C in an insulated flask at atmospheric pressure. Calculate the final temperature of the system.The specific heat of iron is given by: Ĥ (J/g) = 17.3T, where T is in °C.