جية - A - Northern Technical University Technical Eng. College/Kirkuk Fuel and Energy Eng. Tech. Dep. 4th Year Students Final Examination (2022-2023) Subj.: Process of unit operation Date: 6/6/2023 Time: 3 Hours: Morning & Evening Study Note/Answer only four questions, including the first question Q.1: Water is to be cooled in a packed tower from 330 to 295 K by means of air flowing counter currently. The liquid flows at the rate of 275 cm³/m² s and the air at 0.7 m³/m² s. The entering air has a temperature of 295 K and a humidity of 20%. Calculate the required height of tower and the condition of the air leaving at the top. The whole of the resistance to heat and mass transfer can be considered as being within the gas phase and the product of the mass transfer coefficient and the transfer surface per unit volume of column (ha) may be taken as 0.2 s¹. Assuming, the latent heat of water at 273 K = 2495 kJ/kg, specific heat capacity of dry air = 1.003 kJ/kg K, specific heat capacity of water vapour = 2.006 kJ/kg K. Q.2: Answer either A or B [40 Mark] A: In a vessel at 101.3 kN/m² and 300 K, the percentage relative humidity of the water vapour in the air is 25. If the partial pressure of water vapour when air is saturated with vapour at 300 K is 3.6 kN/m², calculate: (a) the partial pressure of the water vapour in the vessel; (b) the specific volumes of the air and water vapour; (c) the humidity of the air and humid volume; and (d) the percentage humidity. B: In a vessel at 1bar and 300K, the humidity of air is equal (0.0068 Kg H₂O/ Kg dry air) and humidity of saturated air equal (0.0282 Kg H₂O/Kg dry air). Calculate: (a) Percentage humidity; (b) Percentage relative humidity; (c) Humid heat. [20 Mark] Q.3: Draw with all formation about (Choose only two) a. Forward feed triple effect evaporation b. Backward feed triple effect evaporation c. Parallel feed triple effect evaporation [20 Mark] Q4: A single effect evaporator is used to concentrate 4536 kg/hr of 20% solid of NaOH solution entering at 60 °C to produce 50% solid. The pressure of sat. steam is 172.4 KPa and pressure in the Vapor space of evaporator is 11.7 kPa. overall heat transfer Coefficient is 1560 w/m².k. Calculate the Steam used, the steam economy and area? given: Boiling point of water at 11.7 A Q
جية - A - Northern Technical University Technical Eng. College/Kirkuk Fuel and Energy Eng. Tech. Dep. 4th Year Students Final Examination (2022-2023) Subj.: Process of unit operation Date: 6/6/2023 Time: 3 Hours: Morning & Evening Study Note/Answer only four questions, including the first question Q.1: Water is to be cooled in a packed tower from 330 to 295 K by means of air flowing counter currently. The liquid flows at the rate of 275 cm³/m² s and the air at 0.7 m³/m² s. The entering air has a temperature of 295 K and a humidity of 20%. Calculate the required height of tower and the condition of the air leaving at the top. The whole of the resistance to heat and mass transfer can be considered as being within the gas phase and the product of the mass transfer coefficient and the transfer surface per unit volume of column (ha) may be taken as 0.2 s¹. Assuming, the latent heat of water at 273 K = 2495 kJ/kg, specific heat capacity of dry air = 1.003 kJ/kg K, specific heat capacity of water vapour = 2.006 kJ/kg K. Q.2: Answer either A or B [40 Mark] A: In a vessel at 101.3 kN/m² and 300 K, the percentage relative humidity of the water vapour in the air is 25. If the partial pressure of water vapour when air is saturated with vapour at 300 K is 3.6 kN/m², calculate: (a) the partial pressure of the water vapour in the vessel; (b) the specific volumes of the air and water vapour; (c) the humidity of the air and humid volume; and (d) the percentage humidity. B: In a vessel at 1bar and 300K, the humidity of air is equal (0.0068 Kg H₂O/ Kg dry air) and humidity of saturated air equal (0.0282 Kg H₂O/Kg dry air). Calculate: (a) Percentage humidity; (b) Percentage relative humidity; (c) Humid heat. [20 Mark] Q.3: Draw with all formation about (Choose only two) a. Forward feed triple effect evaporation b. Backward feed triple effect evaporation c. Parallel feed triple effect evaporation [20 Mark] Q4: A single effect evaporator is used to concentrate 4536 kg/hr of 20% solid of NaOH solution entering at 60 °C to produce 50% solid. The pressure of sat. steam is 172.4 KPa and pressure in the Vapor space of evaporator is 11.7 kPa. overall heat transfer Coefficient is 1560 w/m².k. Calculate the Steam used, the steam economy and area? given: Boiling point of water at 11.7 A Q
Elements Of Electromagnetics
7th Edition
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Sadiku, Matthew N. O.
ChapterMA: Math Assessment
Section: Chapter Questions
Problem 1.1MA
Related questions
Question
![جية - A -
Northern Technical University
Technical Eng. College/Kirkuk
Fuel and Energy Eng. Tech. Dep.
4th Year Students
Final Examination (2022-2023)
Subj.: Process of unit operation
Date: 6/6/2023
Time: 3 Hours:
Morning & Evening Study
Note/Answer only four questions, including the first question
Q.1: Water is to be cooled in a packed tower from 330 to 295 K by means of air flowing counter
currently. The liquid flows at the rate of 275 cm³/m² s and the air at 0.7 m³/m² s. The entering
air has a temperature of 295 K and a humidity of 20%. Calculate the required height of tower
and the condition of the air leaving at the top. The whole of the resistance to heat and mass
transfer can be considered as being within the gas phase and the product of the mass transfer
coefficient and the transfer surface per unit volume of column (ha) may be taken as 0.2 s¹.
Assuming, the latent heat of water at 273 K = 2495 kJ/kg, specific heat capacity of dry air =
1.003 kJ/kg K, specific heat capacity of water vapour = 2.006 kJ/kg K.
Q.2: Answer either A or B
[40 Mark]
A: In a vessel at 101.3 kN/m² and 300 K, the percentage relative humidity of the water vapour
in the air is 25. If the partial pressure of water vapour when air is saturated with vapour at 300
K is 3.6 kN/m², calculate: (a) the partial pressure of the water vapour in the vessel; (b) the
specific volumes of the air and water vapour; (c) the humidity of the air and humid volume;
and (d) the percentage humidity.
B: In a vessel at 1bar and 300K, the humidity of air is equal (0.0068 Kg H₂O/ Kg dry air) and
humidity of saturated air equal (0.0282 Kg H₂O/Kg dry air). Calculate: (a) Percentage
humidity; (b) Percentage relative humidity; (c) Humid heat.
[20 Mark]
Q.3: Draw with all formation about (Choose only two)
a. Forward feed triple effect evaporation
b. Backward feed triple effect evaporation
c. Parallel feed triple effect evaporation
[20 Mark]
Q4: A single effect evaporator is used to concentrate 4536 kg/hr of 20% solid of NaOH solution
entering at 60 °C to produce 50% solid. The pressure of sat. steam is 172.4 KPa and pressure
in the Vapor space of evaporator is 11.7 kPa. overall heat transfer Coefficient is 1560 w/m².k.
Calculate the Steam used, the steam economy and area? given: Boiling point of water at 11.7
A Q](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F5731d011-360a-4303-9b37-9578b2cedd50%2F0a9b7307-f775-46d0-9e1b-ad16731d75c5%2Fteqdbf_processed.jpeg&w=3840&q=75)
Transcribed Image Text:جية - A -
Northern Technical University
Technical Eng. College/Kirkuk
Fuel and Energy Eng. Tech. Dep.
4th Year Students
Final Examination (2022-2023)
Subj.: Process of unit operation
Date: 6/6/2023
Time: 3 Hours:
Morning & Evening Study
Note/Answer only four questions, including the first question
Q.1: Water is to be cooled in a packed tower from 330 to 295 K by means of air flowing counter
currently. The liquid flows at the rate of 275 cm³/m² s and the air at 0.7 m³/m² s. The entering
air has a temperature of 295 K and a humidity of 20%. Calculate the required height of tower
and the condition of the air leaving at the top. The whole of the resistance to heat and mass
transfer can be considered as being within the gas phase and the product of the mass transfer
coefficient and the transfer surface per unit volume of column (ha) may be taken as 0.2 s¹.
Assuming, the latent heat of water at 273 K = 2495 kJ/kg, specific heat capacity of dry air =
1.003 kJ/kg K, specific heat capacity of water vapour = 2.006 kJ/kg K.
Q.2: Answer either A or B
[40 Mark]
A: In a vessel at 101.3 kN/m² and 300 K, the percentage relative humidity of the water vapour
in the air is 25. If the partial pressure of water vapour when air is saturated with vapour at 300
K is 3.6 kN/m², calculate: (a) the partial pressure of the water vapour in the vessel; (b) the
specific volumes of the air and water vapour; (c) the humidity of the air and humid volume;
and (d) the percentage humidity.
B: In a vessel at 1bar and 300K, the humidity of air is equal (0.0068 Kg H₂O/ Kg dry air) and
humidity of saturated air equal (0.0282 Kg H₂O/Kg dry air). Calculate: (a) Percentage
humidity; (b) Percentage relative humidity; (c) Humid heat.
[20 Mark]
Q.3: Draw with all formation about (Choose only two)
a. Forward feed triple effect evaporation
b. Backward feed triple effect evaporation
c. Parallel feed triple effect evaporation
[20 Mark]
Q4: A single effect evaporator is used to concentrate 4536 kg/hr of 20% solid of NaOH solution
entering at 60 °C to produce 50% solid. The pressure of sat. steam is 172.4 KPa and pressure
in the Vapor space of evaporator is 11.7 kPa. overall heat transfer Coefficient is 1560 w/m².k.
Calculate the Steam used, the steam economy and area? given: Boiling point of water at 11.7
A Q
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