Question 62 – The names of the flow streams could be represented by : H1 for first hot stream, H2 for second hot stream, C1 for first cold stream, C2 for second cold stream. Data of supply temperature Ts in degree Celsius : 150 for H1, 170 for H2, 30 for C1, 30 for C2. Data of target temperature Tt in degree Celsius : 50 for H1, 169 for H2, 150 for C1, 40 for C2. Data of heat capacity Cp in kW / degree Celsius : 3 for H1, 360 for H2, 3 for C1, 30 for C2. (a) Find the enthalpy changes, dH for all streams of flow H1, H2, C1 and C2 in the unit of kW. Take note of the formula dH = (Cp) (Tt - Ts). (b) Match the hot streams H1 and H2 with the suitable cold streams C1 and C2 to achieve the maximum energy efficiency.

Answer Posted / kang chuen tat (malaysia - pen

Answer 62 – (a) dH for streams H1 : 3 (50 - 150) = -300 kW. H2 : 360 (169 - 170) = -360 kW. C1 : 3 (150 - 30) = 360 kW. C2 : 30 (40 - 30) = 300 kW. (b) dH (H1 + C2) = 0 kW; dH (H2 + C1) = 0 kW where all heats from hot utilities are supplied to cold utilities. Then H1 is matched to C2 and H2 is matched to C1.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


Please Help Members By Posting Answers For Below Questions

send previousyear question paper for ongc gt 2011 chemical engineering written exam

2905


What particle sizes are electrostatic precipitators used to remove?

587


What are the factors involved in considering the choice of dry screw compressor?

561


What is quicklime and what are the uses?

723


How can you separate hydrogen peroxide into hydrogen and oxygen?

639






How can wet carbon dioxide be responsible for a corrosion problem in iron-containing metals?

618


Explain some of the consequences of an undersized kettle type reboiler?

666


Where barrel pump use?

1392


What are the design considerations for a piping system for the transfer of slurries?

682


What step should be taken in process industries if the process variable is oscillating?

2186


What is carbon sequestration?

578


What are the effects of oils on the properties of Polyolefins?

2336


What effect does choking a vertical thermosiphon have on the heat transfer rate?

654


Explain what are the affinity laws associated with dynamics pumps?

593


Are there any special considerations to be taken into account for combustion ammonia?

540