Enthalpy(H) - Entropy(S) Diagram OR Mollier Diagram

MOLLIER DIAGRAM 

The Mollier Diagram is named after a german Mechanical Engineer Richard Mollier. It is a graphical representation of steam tables, in which Specific Entropy is plotted along the ordinate(X-axis) and Specific Enthalpy along the abscissa(Y-axis). The diagram is divided into two portions by a somewhat horizontal line termed as Saturation Curve.The lower portion(i.e., wet stream region) contains the values of wet stream, whereas the upper portion (i.e.,superheated steam region ) contains the values of superheated stream. 

A Mollier diagram has the following lines:-

     1.    Dryness Fraction lines

     2.    Constant Specific Volume lines

     3.    Constant Pressure lines

     4.    Constant Temperature lines

Dryness Fraction lines :-

These lines are drawn in the wet stream region.i.e., only below the saturation curve (which represents dryness fraction equal to unity). These lines represent the condition of wet steam between various values of enthalpy and entropy. The dryness fraction lines are slightly curved in horizontal direction.

Constant Specific Volume Lines :-

These lines are drawn in both wet steam region and superheated steam region. These lines represent the specific volume of steam between the various values of enthalpy and entropy. The lines are straight in the wet steam region, i.e., below the saturation curve, but are curved upwards in the superheated region i.e., above the saturation curve.

Constant Pressure Lines :-

These lines are also drawn in both wet steam region and superheated steam region. These lines represent the pressure of steam between the various values of enthalpy and entropy. The pressure lines are also straight in the wet steam region, i.e., below the saturation curve, but are curved slightly upwards in the superheated region i.e., above the saturation curve.

Constant Temperature Lines :-

These lines are drawn only in the superheated steam region i.e., above the saturation curve. These lines represent the temperature of steam between the various values of enthalpy and entropy . The temperature lines are slightly curved in the horizontal direction.

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Mumbai University | Chemical Engineering Branch | Third Year Semister-V Subject Mass Transfer Operations(MTO - I) | Guidance | Marks Distribution | List of Questions

Mass Transfer Operations - I 

a) Nick Name by Student's :- MTO-I.

b) Short Information of Subject :-

i) Theory Examination :- 100 Marks.
1) Question paper will comprise of 7 questions, each carrying 20 marks.
2) Total 5 questions need to be solved.
3) Question No.1 will be compulsory and based on entire syllabus.
4) Remaining Questions will be randomly selected from all the Chapters and will be mixed in nature.

ii) Term Work :- 25 Marks.
The distribution of marks for the Term Work will be as follows :-
Attendance (Theory and Practicals) : 05 marks.
Class Tutorials on entire syllabus : 10 marks.
Test (atleast 1) : 10 marks

iii) Practical :- 25 Marks.
As per the Mumbai University rules you will have to perform any one Experiment which will be given to you by the External Examiner from the Experiments that you have performed during Regular College Practicals.

Total Marks :- 150 Marks.

Mass Transfer Operations - I is basically a Theory subject but if you have to score well you will have to do Numericals also . On average basis the Question paper comprises of 90 marks theory and 50 marks Numericals. Scoring in these subject is very easy. No need of going to any coaching classes you can score good in these subject studying at home.

c) Best Book to refer :- K.D. Patil.

Mass Transfer Operations – I (MTO-I) Set of Questions (Theory ) :-

Reference Book :- K.D. Patil.

Set of questions :

Define :

1)Relative Humidity – 6.3

2)Equilibrium Moisture

3)Humid heat & volume

4)Diffusion & Diffusion Coefficient

5)Critical moisture content

6)Mass Transfer Coefficient – 3.2

7)Dew Point – 6.4

8)Unbound & Bound moisture

9)Dry bulb temperature – 6.3

Derivations :-

1)For a binary system show that D_AB  &  D_BA  - 2.12

2)Derive  Steady state flux equation for gas A diffusing in non-diffusing gas B

3)Derive the equation for operating line for co-current operation.

4)Derive equation for adiabatic saturation curves – 6.5

5)Derive the equation for operating line for counter current operation.

6)Derive expression for wet bulb temperature – 6.6

7)Derive equation for:  a)Equimolar counter diffusion b)Diffusion through stagnant gas.

8)Derive the relation between overall mass transfer coefficient and individual mass transfer coefficient when the mass transfer in both gas & liquid phase is controlled

9)Derive the flux equation for liquid A diffusing in stagnant liquid B .

Short Notes on :-

1)Surface renewal theory

2)Requirements of a good solvent for absorption – 5.11

3)Various types of packings used in packed tower – 7.17

4)Theory of wet bulb temperature – 6.6

5)Hydrodynamics of Packed Column – 7.18

6)Problems associated with Tray tower operation – 7.8

7)Properties of ideal solution

8)Absorption with chemical reaction – 5.42

9)Venturi Scrubber – 7.23

10)Typical rate of drying – 8.4

11)Drum dryer or Rotary dryer – 8.16

12)Two film theory of mass transfer

13)Compare Tray & Packed tower – 7.23

14)Difference between Natural & Forced draft cooling tower

15)Minimum liquid to gas ratio – 5.9

16)Effect of temperature and pressure on diffusivity

17)Humidification & Dehumidification Operations – 6.2

18)Construction & Working of Tray Dryer – 7.9

19)Ficks Law – 2.11

20)Sparged Vessel – 7.2

21)Tray efficiency – 7.13

22)Psychrometric chart

23)Analogy between Heat, Mass & Momentum transfer

24)Different theories for evaluation of Mass Transfer Coefficient

25)Concept of HTU, NTU & HETP – 5.36

26)Diffusion in porous solid

27)Spray dryer – 8.16

28)Penetration Theory - 3.7

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Mumbai University | Chemical Engineering Branch | Third Year Semister-V Subject Solid Fluid Mechanical Operations(SFMO) | Guidance | Marks Distribution | List of Questions

Solid Fluid Mechanical Operations

a) Nick Name by Student's :- SFMO.

b) Short Information of Subject :-

i) Theory Examination :- 100 Marks.

1) Question paper will comprise of 7 questions, each carrying 20 marks.
2) Total 5 questions need to be solved.
3) Question No.1 will be compulsory and based on entire syllabus.
4) Remaining Questions will be randomly selected from all the Chapters and will be mixed in nature.

ii) Term Work :- 25 Marks.

The distribution of marks for the Term Work will be as follows :-
Attendance (Theory and Tutorial) : 05 marks.
Class Tutorials on entire syllabus : 10 marks.
Test (atleast 1) : 10 marks

iii) Practical :- 25 Marks.

As per the Mumbai University rules you will have to perform any one Experiment which will be given to you by the External Examiner from the Experiments that you have performed during Regular College Practicals.

Total Marks :- 150 Marks.

Solid Fluid Mechanical Operations (SFMO) is almost a Theory Subject, Max. to Max. 30-40 Marks Numericals may appear in exam, it’s very easy to score well in this subject . This subject needs lots of mugging up skills as the paper mostly comprises of theory questions. It mostly includes the study of various types of size reduction equipments, Filtration equipments, Seperation equipments, Various laws & theories related to it etc. Also there are many diagrams in these subject & Attempting full 100 marks paper is not that easy.

c) Best Book to refer :- Prof. A. P. Kulkarni ( Everest Publication )

d) Short view of Syllabus :-

In all there are 8 Chapters in SFMO :-

1) Introduction

2) Size Reduction

3) Mechanical Seperation

4) Filtration

5) Mixing

6) Fluid – Solid System

7) Handling Of Solids

8) Fluid Mechanics

Solid Fluid Mechanical Operations (SFMO) Set of Questions(Theory) :-

Reference Book :-  Prof. A. P. Kulkarni ( Everest Publication )

Set of Questions :-

10 Marks Theory Questions

1)Explain Construction and Working of any two Filtration Equipments.

2)Draw diagram of thickener and explain different zones in it.

3)Explain working principle of Crushing Rolls with diagram.

4) Explain principle of Floatation.Give it's applications and list the equipments of Floatation.

5)Explain any 2 types of mixers used for mixing cohesive solids.

6)Explain the principles of Agglomeration and equipments used for it OR Explain Size Enlargement Methods and give it's Objectives,Applications and Techniques.

7)Explain the Construction and working of Centrifuge.

8)Explain Open & Closed circuit operations with diagram.

9)Explain how compressibility of cakes can be expressed in a filtration experiment. Also write Emperical expressions for it.

Derivations :

1)Derive the equation for calculating the area of the thickener.

2)What is screen effectiveness ? Derive expression for it.

3)Explain the Degree of mixing & Rate of mixing in dry solids.

4)With mathematical expression explain Average Particle size,Mass mean diameter,Volume mean diameter & Volume shape factor.

5)Show that in a non-washing type of Plate and Frame Press operating at constant pressure,the optimum cycle occurs at a time of filtration equals the time lost in operating and cleaning of Press .Neglect filter medium resistance.

6)What is angle of internal friction ? Derive expression for it.

Difference Between :-

1)Cumulative & Differential analysis

2)Pressure & Vaccum filter

3)Ideal & Actual screen

4)Gravity & Centrifugal settling.

 5 Marks Questions :-

 Generally asked as write Short Notes on:

1)Different crushing laws

2)Centrifugal Sedimentation

3)Variables by which screening operations are affected.

4)Electrostatic Precipitator

5)Filter aids

6)Trommels

7)Screw Conveyers

8)Elutriator

9)Jigging & Tabling

10)Hammer Mill

11)Ball Mill & it's critical speed

12)Jaw crusher

13)Sigma mixer

14)Kynch theory of sedimentation

15)Prilling

16)Ribbon Blenders

17)Fabric Filters

18)Flocculation

19)Hydraulic jig

20)Rotary vaccum filter

21)Angle of repose

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