1. MECHANICAL SEPARATIONS

2. 6/2/20162 Course Outline Introduction to Separation Processes Role of Mechanical Separations in Chemical Engineering Fundamentals of different mechanical separations; Filtration, Sedimentation, Clarification, Flotation, Centrifugal separations, Jigging, tabling, magnetic and electrostatic separations, Sonic Agglomeration Different types of mechanical separation equipment

3. 6/2/20163 Introduction to Separation Processes Separation process is used to transform a mixture of substances into two or more distinct products. The mixture can be a combination of any two or more states: solid-solid, solid-liquid, solid-gas, liquid-liquid, liquid-gas, gas-gas, solid-liquid-gas mixture, etc.

4. 4  Phase creation  Phase addition  Barrier  Solid agent  External field Separation Process Mechanisms

5. 6/2/20165 How separation is carried out? In order to affect a separation, separating agents are needed in the form of either: Energy input (heat, electricity, magnetism,) Withdrawal of energy ( cooling, freezing) Medium (filter, membrane, screens) May be any phase as well as any chemical

6. 6/2/20166 Classification of Separation processes The classification can be based on the means of separation; 1. Mechanical Processes 2. Chemical processes

7. 6/2/20167 Why Separations are needed? Isolating valuable chemicals from mixtures Removing impurities from raw materials Purification of products

8. 6/2/20168 Mechanical Separations Mechanical Separations are applicable to heterogeneous mixtures, not to homogenous solutions. The techniques are based on the physical differences b/w the particles such as size, shape or density.

9. 9  Relatively less Energy Requirements  Ease of Operation  Ease of Maintenance  No special Feed pretreatment required  Not applicable for separating Components in homogeneous phase  Not versatile i.e. in same state may be one element can be separated and other don’t.  Applicable to low flow rates Advantages Disadvantages

10. 6/2/201610 Classification  On the basis of characteristics  Depending on the difference in size or shape  Depending on the difference in phase density  Depending on fluid and particle mechanics  Depending on surface, electrical or magnetic properties  On the basis of phases involved  S-S  L-L  G-L  L-G  S-L  L-S  S-G

11. 6/2/201611 Our focus will be the…  Solid – Solid Separation  Solid – Liquid Separation  Solid – Gas Separation

12. 12  Objective – to separate the mixture of solids into two or more fractions  Dry basis  Screening  Electrostatic  magnetic  Wet basis  Classification Solid – Solid Separation

13. 13  Objective – to separate the solids and liquid from each other  Filtration  Sedimentation – gravitational settling  Centrifugal separators Solid – Liquid Separation

14. 14  Objective – to separate the solids from gas  Filtration  Gravitational settling  Centrifugation Solid – Gas Separation

15. 6/2/201615 Filtration

16. 6/2/201616 Sedimentation

17. 6/2/201617 Centrifugal Separation

18. 6/2/201618 Magnetic Separation

19. 6/2/201619 Electrostatic Separation