Question 49 - 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.
- 1 Answers
- 1768 Views
- I also Faced
- E-Mail Answers
Answer Posted / kang chuen tat (malaysia - pen
Answer 49 - (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 View All Answers
what is the hearth and arch pressure in furnace?
What is the procedure to estimate the friction factor involved in heat exchanger tubes?
Explain the method adopted to minimize shell side pressure drop in a shell?
Explain how can you determine the largest impeller that a pump can handle?
What is difference between overall heat transfer coefficient & individual heat transfer coefficient?
Are there any general rules that should be considered when designing a slurry piping system?
What do you understand by wet bulb globe temperature?
What is an effective means of removing silicone from aluminum?
What are the problems that are associated with the expansion joints?
When using a pumping loop to mix two miscible fluids in a tank, when can the content are considered well mixed?
What significance the angle of repose holds in the chemical industry, explain?
i am a student of thapar university final year.can anybody please help me with the exam pattern of the companies:engineers india ltd. ; iocl ; UOP, HPCL. If psbl plz send me the previous years questions on this email id k_arora1987@yahoo.com. i d be really greatful
I am pg student of chemical engg. I am intrested Heat Transfer Subject . I want information about advance heat transfer related PG PROJECT
How can you determine the proper pipe thickness for a slurry line?
What does capacitor load means? How does it connect?
