PROCESS DESIGN - EXAMPLE 21.1 : According to rules of thumb in chemical process design, consider the use of an expander for reducing the pressure of a gas when more than 20 horsepowers can be recovered. The theoretical adiabatic horsepower (THp) for expanding a gas could be estimated from the equation : THp = Q [ Ti / (8130a) ] [ 1 - (Po / Pi) ^ a ] where 3 ^ 3 is 3 power 3 or 27, Q is volumetric flowrate in standard cubic feet per minute, Ti is inlet temperature in degree Rankine, a = (k - 1) / k where k = Cp / Cv, Po and Pi are reference and systemic pressures respectively. (a) Assume Cp / Cv = 1.4, Po = 14.7 psia, (temperature in degree Rankine) = [ (temperature in degree Celsius) + 273.15 ] (9 / 5), nitrogen gas at Pi = 90 psia and 25 degree Celsius flowing at Q = 230 standard cubic feet per minute is to be vented to the atmosphere. According to rules of thumb, should an expander or a valve be used? (b) Find the outlet temperature To by using the equation To = Ti (Po / Pi) ^ a.



PROCESS DESIGN - EXAMPLE 21.1 : According to rules of thumb in chemical process design, consider the..

Answer / kangchuentat

PROCESS DESIGN - ANSWER 21.1 : (a) a = (k - 1) / k = (1.4 - 1) / 1.4 = 0.286. Ti = 25 degree Celsius to degree Rankine = (25 + 273.15) (9 / 5) = 536.67 degree Rankine. THp = Q [ Ti / (8130a) ] [ 1 - (Po / Pi) ^ a ] = 230 [ 536.67 / (8130 x 0.286) ] [ 1 - (14.7 / 90) ^ 0.286 ] = 21.469 horsepowers which is more than 20 horsepowers for expander to be used. (b) To = 536.67 (14.7 / 90) ^ 0.286 = 319.629 degree Rankine. The answer is given by Kang Chuen Tat; PO Box 6263, Dandenong, Victoria VIC 3175, Australia; SMS +61405421706; chuentat@hotmail.com; http://kangchuentat.wordpress.com.

Is This Answer Correct ?    0 Yes 0 No

Post New Answer

More Chemical Engineering Interview Questions

Suppose you have hot fluid and cold water, what fluid you should flow in shell side and tube side in a shell and tube heat exchanger and why

6 Answers  


Is there any way to remove residual product left in pipes after a batch operation?

0 Answers  


What is the Import Procurement Cycle ? and what are the customization steps in SAP ?

0 Answers   Siemens,


Are there any general rules for flushing slurry lines?

0 Answers  


What is the principles of crayogenic expansion turbin

1 Answers   Goyal Group,






Sir, what is the significant of mmWC what is the definition? How can we Establish the DEMO apparatus in Plant/process lab. ? Arun Kumar Lupin Ltd Bhopal. 9926433779

2 Answers   Lupin,


What are the uses of quicklime?

0 Answers  


what is factories act?tell about factories act?

1 Answers  


What are the methods involved to test helium leak testing in a vacuum system?

0 Answers  


I will complete chemical engg next yr from a deemed university. Earlier I dropped 2 yrs after std 12th. Then I got 2 yr back while completing engg, due to reasons beyond my control. Will I face any problem while applying for job. More so not many core companies come to our collg for placement. So i want to know which all companies can I apply to get a job?

0 Answers  


Experiment constitutes 1000 ml of 10 ppm dye solution and 0.2 g catalyst mixed in beaker. How to calculate the initial of concentration?

1 Answers  


What does the catalytic converter on an automobile do?

0 Answers  


Categories
  • Civil Engineering Interview Questions Civil Engineering (5085)
  • Mechanical Engineering Interview Questions Mechanical Engineering (4451)
  • Electrical Engineering Interview Questions Electrical Engineering (16632)
  • Electronics Communications Interview Questions Electronics Communications (3918)
  • Chemical Engineering Interview Questions Chemical Engineering (1095)
  • Aeronautical Engineering Interview Questions Aeronautical Engineering (239)
  • Bio Engineering Interview Questions Bio Engineering (96)
  • Metallurgy Interview Questions Metallurgy (361)
  • Industrial Engineering Interview Questions Industrial Engineering (259)
  • Instrumentation Interview Questions Instrumentation (3014)
  • Automobile Engineering Interview Questions Automobile Engineering (332)
  • Mechatronics Engineering Interview Questions Mechatronics Engineering (97)
  • Marine Engineering Interview Questions Marine Engineering (124)
  • Power Plant Engineering Interview Questions Power Plant Engineering (172)
  • Textile Engineering Interview Questions Textile Engineering (575)
  • Production Engineering Interview Questions Production Engineering (25)
  • Satellite Systems Engineering Interview Questions Satellite Systems Engineering (106)
  • Engineering AllOther Interview Questions Engineering AllOther (1379)