The document discusses various filtration methods, including their principles, operations, advantages, and disadvantages, focusing on types such as plate & frame filters, rotary drum filters, membrane filters, and cartridge filters. It covers the mechanisms behind filtration, criteria for selecting filter media, and the applications of filtration in various processes like sterilization and purification. Additionally, it highlights the importance of factors like particle size, liquid viscosity, and operational conditions in the filtration process.

1. Filtration
By
Yogeshwary Bhongade
Assistant Professor
Gondia college of Pharmacy, Gondia

2. UNIT-IV
1- Filtration
• Objectives, applications, Theories & Factors influencing filtration, filter
aids, filter medias.
• Principle, Construction, Working, Uses, Merits and demerits of –
Plate & frame filter,
Filter leaf,
Rotary drum filter,
Meta filter
Cartridge filter,
Membrane filters &
Seidtz

3. Filtration
• It is the process of separation of particle from
fluid by passing slurry through a permiable
membrane.
Slurry- Suspention of particle in Liquid
Filter Medium-Medium through which slurry
passed
Residue- Separated solid on medium
Filtrate- Clear liquid passing through medium

4. Objectives
• For clarification
• Cake filtration
• Sterile Filtration
• Ultra filtration

5. Applications
• Fitration of bacteria and particulate contamination
• Sterilization of heat labile solution
• Separation of bulk product from reaction mixture
• purification of water
• Removing of solid or suspended olis from aqueous solution
• Separation of alcohol from fermentation reactor
• Treatment of waste liquid

6. Mechanism of filtration
1. Staining
2. Impringment
3. Entanglement
4. Electrostatic force

7. Filter Media
• It is the medium through which slurry is passed to get filtrate
or
• The surface on which solids are retained after filtration process is
called as Filter Medium.

8. Properties of Ideal Filter Media
• Sufficient Mechanical Strength
• Chemically inert
• Minimum resistance to flow filtrate
• High retention power
• Should allow easy removal of cake
• Should not absorb dissolved material
• Not swell in contact with filtrate

9. Selection of Filter Media
• Selection of Filter Media Depends on following
• Size of Particles to be filtered
• Nature of Product to be filtered
• Amount of liquid to be filtered

10. Filter Media
1. Woven Mendia
- Cotton Cloth
-Nylon Cloth
- Woven wire cloth
2. Non Woven Media
3.Membrane filter
4. The depth type Media
- Fibrous Medium
- Porous Medium
- Bed of Granular solid

11. Filter Aid
• Special type of filter medium, which form a fine surface deposite that
form porous, non- compressible cake over filter medium, thus
reducing resistance to flow
• Act as depth filter
• Maintain Flow

12. Ideal Filter Aid
• Should form porous cake
• Suitable particle size
• Impurities free
• Free from moisture
• Should be innert
• Should maintain suspended
Precoating
Body Mix

13. Filtration Equipments
Classificaton Based on Type of Driving Force

14. • Classification Based on Type of Operation
Type Of
Operation
Batch Continuous

15. • Classification Based on End Product
Based on
End Product
Filter Cake
Clarifying
Filter

16. • Choice of filter govern by specific requirement
1. Properties of Liquid eg. Viscosity
2.Objectives of Filtration eg. Recovery of solid/ sterilization/clarification
3.Properties of solid eg. Particle size, shape, compressibility
4.Whether Cake is to be washed
5.Operating Temperature and Pressure
6. Desired flow rate

17. Plate & frame filter
Principle
• Based upon surface filtration
• the slurry enters the frame by pressure and flows through the filter
medium.
• The filtrate is collected on plates and sent to outlet
• surface area increased with the help of plate and frames then large
volume of slurry can be proceed
• The Filter press is made of two types of units, plate and frames.

18. • Usually made of aluminium alloy.
• Sometimes, these are also lacquered for protection against corrosive
chemicals and made suitable for steam sterilization.

21. Frame
• It contains a open space inside wherein the slurry reservoir is
maintained for filtration and an inlet to receive the slurry.
• It is indicated by two dots in description. Slurry inlet Handle to rest on
rod
• Frames of different thickness are available.
• It is selected based on the thickness of cake formed during filtration.
• Optimum thickness of frame should be chosen.

22. Plate
• The plate has a studded or grooved surface to support the filter cloth and
an outlet. It is indicated by one dot in description. Through channels
Filtrate outlet
• Plate supports the filter medium, receiving the filtrate and outlet.
• The filter medium usually cloth is interposed between plate and frame.
• Plate, filter medium, frame, filter medium and plate are arranged in
sequence and clamed to a supporting structure.
• It is normally described by dots as 1.2.1.2.1 so on.
• A number of plates and frames are employed so that the filtration area is
as large as necessary.
• ts controlled by valves.

23. • Number of filtration units are operated in parallel.
• Channels for slurry inlet and filtrate outlet can be arranged by fitting
eyes to the plates and frames, these join together to form a channel.
• In some types only one inlet channel is formed, while each plate is
having individual outle

24. Working of filter press
• Working can be divided into two steps-
1. Filtration operation
2. Washing operation Filtration operation

25. Advantages:
1- Construction is very simple and a wide variety of materials can be
used.
2- It provides a large filtering area in a relatively small floor space. 3- It
is versatile, the capacity being variable according to the thickness of the
frames and the number used.
4- The construction permits the use of considerable pressure difference.
5- Efficient washing of the cake is possible.
6- Operation and maintenance is straightforward , because there no
moving parts, filter cloths are easily renewable and, because all joints are
external, any leaks are visible and do not contaminate the filtrate.

26. Disadvantages:
1- It is a batch filter, so it is a time consuming.
2- The filter press is an expensive filter, the emptying time, the labour
involved, and the wear and tear on the cloths resulting in high costs.
3- Operation is critical, as the frames should be full, otherwise washing
is inefficient and the cake is difficult to remove.
4- The filter press is used for slurries containing less about 5 % solids
5- In view of the high labour costs , it is most suitable for expensive
materials.e.g.the removal of precipitated proteins from insulin liquors.

27. Filter leaf
• It is the simple form of batch filter
consisting of dranage canal converted
with filter cloth
Principle
• Surface filtration
Construction
• It consist of grooved metal frame work
over which filter cloth is fixed.
• The groved frame encloses drainage
screen.
• The outlet for filtrate connected to inside
the frame.

28. Working
• The filter leaf is placed in a vessel containing the liquid to be filtered.
• When vacuum is applied , the pressure inside the leaf is decreased.
• Due to the difference in external and internal pressure inside the leaf,
the liquid moves inside the filter through the filter cloth.
• The filtrate is collected in the receiver , and cake gets collected on
outside of the cloth.

29. Advantages:
Liquid can be filtered from any vessel .
Filter cake can be removed simply by washing or blowing air.
It is very economical .
Disadvantages :
It is not effective when solid content in the liquid is more than 5%.

30. Meta filter
Also known as Edge filter
Principle
• It fuction as surface filter and separate the particle by staining through the
tappering channels formed by series of ring with semicircular projection.
Construction
• It is made up of a series of metal ring made of ss packed on grooved rod.
• ring have internal diamete 15 mm and external diameter 22mm

32. Working
• The entire assembly is placed inside a pressure vessel , containing the
liquid to be filtered.
• When vacuum applied, liquid will flow from outside to inside.
• The clear liquid is collected in to a receiver from the top.
• The pack of rings acts as a base on which the true filter medium is
supported.

33. Advantage
• It possess considerable strength and hence can withstand high
pressure.
• It is economical.
• The corrosive liquids can be filtered without any problem.
• Cake can be removed effectively without any difficulty.
Use
• Used mostly for clarification of syrups , elixirs and parenteral
solutions .

34. Rotary drum filter
• Rotary drum filter is continuous filter that can handle slurries with high
proportion of solid, with simultaneously removal of cake.
• It operate on vacuum
Construction
• It consist of hallow metal cylinder on which filter cloth is mounted with
support of mesh.
• the cylinder has five sections-
1.Pickup zone
2.Drainage zone
3. Washing zone
4. cake removal zone
5. Drying zone

36. Working
• The drum rotate slowly and pickup slurry from the feed through
(pickup zone).
• The slurry is filtered under vacuum and the cake built on the filter
cloth.
• From the fewatering zone the water is completely removed from cake.

37. Advantages
• Automatic and continuous
• low labor cost
• Can handle large ammount of slurry
• Speed of drum can varry to control the thickness of cake
Disadvantages
• Difficult to maintain as it contain may moving part
• Cake may crack due to vacuum, making washing difficult
• Small pressure difference(liquid may boil)
• not suitable for gelatinous solids.

38. Membrane filters
Construction
Membrane filters are made of thin and flat membranes of cellulose derivatives,
such as cellulose acetate and cellulose nitrate.
• Thickness: 50-150 µ
• 400-500 million pores
• Pores are uniform in size and occupy 80% of filter volume.
• A membrane filter is fixed in a metallic holder before its use.
• Selection of membrane filter depends on particles to be removed.
• Pore size (in µ) Particles removed 0.2 All bacteria 0.45 All coliform group
bacteria 0.8 All air born particles 1.
• All Non living particles considered dangerous in I.V. Fluid. 5 All Significant
cell from body fluid 4. Membrane Filters 12

39. Advantages
• The processes can function effectively at low temperatures.
• Energy requirements are low.
• Processes are relatively simple to scale up.
• Membranes can be manufactured in a uniform and highly precise manner.
Disadvantages
• It cannot be used for filtration of organic solvents, such as alcohols, ketones,
esters and chloroform.
• Pre-filtration is often required to avoid rapid clogging of a membrane.
• Equipment cost can be high.
• If the membrane manufacturing process is not precisely controlled, membranes
with wide pore size distribution may result, giving poor separation
performance.
• Uses Mainly used for sterilisation of both aqueous and oily liquids

40. Cartridge filter
Principle
• The principle behind this filter is water is pushed through thin porous membrane
in which pre-filter and membrane filter are combined into the single unit.
• as a result the particals are retained on the surface
Construction
• it consist of cylindrical centrifugation having disposable filter media which are
made up of platic or metal.
• The filter consist of cartridge one of which act as prefilter while another one act
as actual filter for filtration.
• The cartridges are enclosed in holder. There is also provsion for slurry and
filtrate outlet.
• At the bottom discharge cake is collected which is removed from bottom.

41. Working
• A slurry is pump into cartridge holder
through the inlet. it passes through
cartridge filter.
• The filtration occures due to mechanism
of staining.
• The particle get attached to the surface
while clear liquid passes to the centre
• The filtrate ove up and collected
through the outlet

42. Uses
• Preparation of sterile solution(Parentral and opthalmic)
• Water treatment plant

43. Advantages
• Suitable for sterile preparation.
• low contamination
• easy to dissasemble
• Filter media can be reused
• cartridge with self cleaning devices are useful
• cartridge are not brittle, whwn they dry.
• Can use continuous

44. Disadvantages
• To much cost

45. Seitz filter
Principal
• Filtration of asbestos pad filter disc
Construction
• Funnel like structure.
• Upper part
• Asbestos pad filter disc
• Lower part

46. Working
• Join parts then add slurry.
Slurry deposit on asbestos pad filter disc and Filtrate will pass.
Application
• Serum sterilization.
• Sterilization.
Advantages
• Contaminate filters
• Simple to use
• Useful for viscous solutions.
Disadvantages
• delicate

47. THANK YOU