A packed bed reactor is used to produce styrene by the vapor phase catalytic dehydrogenation of ethylbenzene. Steam is used to prolong life of the catalyst...

 

The following reactions may be significant:

 

C6H5C2H5.  <———kst———>C6H5CH=CH2 +H2

 

EB<———kst——>ST+H₂

 

Log10(kst)=(-11370 /4.575T )+0.883

 

Dlta H =53600 BTU/bmol

 

where T is in degrees Kelvin; kst = lbmol styrene/ (h-atm-lb catalyst.

 

The overall equilibrium constant

 

T, (°C).      400                      500.                      600.         700

 

Kp             1.7 x 10^-3     2.5 x 10^-2        2.3 x 10^-1       1.4

 

Additional data

 

Vapor phase reaction

 

Feed temperature = 1124 F

 

Feed pressure = 20 psia

 

Feed molar flow rate = 1206 lbmole/h

 

1- From any available source, find the rate of reaction as a function of (mole fraction, concentration or partial pressure

 

2- Find the activation energy of the reaction

 

3- Design a reactor that can handle this reaction according to the given data

 

4- Mention the design constraints and assumptions

 

5- Verify the design using HYSYS and Polymath software

 

6- Mention the utility requirement if possible

 

1. 7- Mention any environmental health and safety impact of this process 8- Mention any economic, social, and cultural issues

The reverse water-gas reaction is an undesirable side-reaction during industrial hydrogen production:
CO2 + H2 ↔ CO + H2O
(A)What is the equilibrium composition of a mixture at 1500K that initially contained 40 mol. % CO2,
30 mol. % H2, 20 mol. % CO and 10 mol. % H2O? Employ canonical partition functions.
(B) Employ the JANAF table data to find this mixture composition at equilibrium at 1500K and
compare it to the results in part (A). Do they agree? How can one explain the differences?

A multiple-effect evaporator is an apparatus for efficiently by means of the heat from steam to evaporate water. Water is boiled in a sequence of vessels, each held at a tower pressure than the last. Because the boiling temperature of water decreases as pressure decreases, the vapour boiled off in one vessel can be used to heat the next. and only the first vessel requires an external source of heat. While in theory evaporators may be built with an arbitrarily large number of stages, evaporators with more than four stages are rarely practical except in systems where the liquor is the desired product such as in chemical recovery systems where up to seven effects are used. Multiple effect evaporation commonly uses sensible heat in the condensate to preheat liquor to be flashed. In practice the design liquid flow paths can be somewhat complicated in order to extract the most recoverable heat and to obtain the highest evaporation rates from the equipment. The evaporator is used to remove the solvent from the sotution. In the four stage evaporation system used in sugar cane industries, a 50% by mass sugar solution is concentrated to by 65% by evaporating an equal amount of water in each of four stages. With total input of 50,057 lb/h, a product stream of 35,057lb/h is produced.

 Draw the block flow diagram?

 Write the general material balance for the system?

 Determine the compositions of intermediate stream?

 Whether the mass flow rate of each stream can be calculated? If yes or no, justify your answer

 Perform the Degree freedom of analysis of overall system and individual units? Write the strategy to solve the problem.

A multiple-effect evaporator is an apparatus for efficiently by means of the heat from steam to evaporate water. Water is boiled in a sequence of vessels, each held at a lower pressure than the last. Because the boiling temperature of water decreases as pressure decreases, the vapour boiled off in one vessel can be used to heat the next. and only the first vessel requires an external source of heat. While in theory. evaporators may be built with an arbitrarily large number of stages, evaporators with more than four stages are rarely practical except in systems where the liquor is the desired product such as in chemical recovery systems where up to seven effects are used. Multiple effect evaporation commonly uses sensible heat in the condensate to preheat liquor to be flashed. In practice the design liguid flow paths can be somewhat complicated in order to extract the most recoverable heat and to obtain the highest evaporation rates from the equipment. The evaporator is used to remove the solvent from the solution. In the four stage evaporation system used in sugar cane industries, a 50% by mass sugar solution is concentrated to by 65% by evaporating an equal amount of water in each of four stages. With total input of 50,0XX lb/h, a product stream of 35,0XX lb/h is produced.

 Draw the block flow diagram?

 Write the general material balance for the system?

 Determine the compositions of intermediate stream?

 Whether the mass flow rate of each stream can be calculated? If yes or no, justify your answer.

 Perform the Degree freedom of analysis of overall system and individual units?

 Write the strategy to solve the problem.