Introduction to Centrifugation For The Biotechnology Industry

Transcription

1 Introduction to Centrifugation For The Biotechnology Industry Speakers: Aaron Allen Jacobs Engineering Group Larry James CRB Consulting Engineers Inc. Mark Trotter Sartorius Stedim Biotech Michael Rohr Westfalia Separator Inc 1

2 1. Introduction to Sedimentation Centrifugation Principles & Design 2. Overview of Process Parameters for Optimization 3. Typical Scope of Supply for Skid Systems 4. Typical Applications for Biotech Centrifuges 5. CIP Approach 2

3 1. Introduction to Sedimentation Centrifugation Principles & Design 3

4 Typical Fermentation Process Flow Sheet Including Centrifuge Typical feed concentration 1-2 % (v/v) depends on vaccine Mammalian cells 4

5 Particle Size Distribution Particles of different sizes and densities must be removed by the centrifuge. The large ones are easier than the small rate limiting ones. 5

6 Calculation of the Settling Speed (Resisting force) (Lifting force) Spherical particle (Weight) F With w = Follows: F F c w ρ A 2 c w = 24 Re A G F w f for = 3 π η v f 2 g d 3 πd p = ρl g 6 3 πd p = ρ s g 6 = c w πd 4 p ρ 2 f v Re = d v p g ρ f < 0,5 η p v g f 2 g F G =F A + F W v g = ρ 18 d η f 2 p g Stoke s Law of settling 6

7 Gravity Settling Volume Rate = Residence Time H1 Settling distance Velocity < T res = Capture H2

8 Short Settling Distance Additional Settling Surface Particles settle from the fluid via gravity in the spaces between the plates H1 Residence Time Capture Surface Area

9 Centrifugal Force Residence Time Surface Area Capture Centrifugal Acceleration

10 Particle Separation in the Centrifuge dlimit Vr Vfl Vf ω Q Vf Vfl Vr dlimit Q ϕ ω dlimit : min. particle size capured Q : flow rate Vf : centrifugal speed η : dyn. viscosity Vfl : flow speed ρ : delta density Vr : resulting speed ω : speed of rotation d 2 limit ~ Qh / (Drw2 ) 10

11 Ejecting Solids Clarification Capacity Liquid Clarity Flow Rate Solids Capacity Sediment Space Discharge Volume Solids Flow Rate

12 Process Flowpath Through Separation Area Feed in Centrate out Low Shear feed zone Disc Stack Sediment Holding Space Peripheral Solids Discharge 12

13 Ejection of Solids Control Benefits of variable shot control Higher product yield (less losses) Shorter harvest time (no buffer flushes) Largest small partial ejection Medium small partial ejection Smallest small partial ejection 13

14 Self-Cleaning Stacked-Disc Centrifuge With Automatic Solids Ejection 14

15 Disc Comparison Electro polished disc Standard disc

16 Centripetal Pump Discharge - Pumping Liquid Clarified rotating liquid from the disc stack enters the upper discharge chamber within the bowl and is picked up by the Stationary Centripetal Pump head and Discharges through the channels under Pressure.

17 1. Introduction to Sedimentation Centrifugation Principles & Design 2. Overview of Process Parameters for Optimization 17

18 1. Feedrate to centrifuge > monitor centrate quality > in line turbidity > spin down analysis > filter testing 2. Shear force via bowl rpms > cell culture only > HydroHermetic Feed > centrate backpressure 3. Solids ejection interval > usually maximize interval > monitor centrate quality 4. Solids ejection volume > adjust to minimize losses 5. Scale up using Sigma > see next slide 18

19 Process Parameter Considerations For Mechanical Separation Product-Related Parameters Density Difference Viscosity of Carrier Liquid Particle Size & Distribution Solids consistency Surface Tension Gravitational Velocity V g = Particle Dia 2 x Density X g 18u (viscosity) Application Related Parameters Stokes Separation Factors Settling Distance Residence Time Time at Laminar Flow Settling Surface Area G Force I/e Bowl Speed Terminal Settling Velocity V c = V g x RPM 2 x R Gravity % of Phases Present Desired Purity Flow Required Temperature Corrosion / Erosion Operational Restrictions, xp etc Clear Centrate or Dry Solids?

20 Throughput via Effective Clarification Area d = Particle diameter (m) Dq = Density difference (kg/m3) u = Dynamic viscosity (kg/ms) g = Gravity (9.8 m/s/s) n = Speed (rpm) z = Number of discs e = Tan of disc angle r1= Outer disc radius (m) r2= Inner disc radius (m) Q = V s x T Q = Throughput rate (ml/s) Area Equivalent T Q = d 2 x Dq x g 18 u x 2p 3 g x p x n 30 2 x z x e x ( r r 2 3 ) W 2 Stokes V s Angular velocity

21 1. Introduction to Sedimentation Centrifugation Principles & Design 2. Overview of Process Parameters for Optimization 3. Typical Scope of Supply for Skid Systems 21

22 Whisperfuge Bench Top Centrifuge 22

23 Skid Mounted Centrifuge System CSC SIP / CIP 23

24 CSC 20 Package Unit for the recovery of human vaccines 24

25 CSE Skid Package CIP / SIP 25

26 CSE Skid Package CIP / SIP 26

27 CSE 170 SIP-Package unit 27

28 1. Introduction to Sedimentation Centrifugation Principles & Design 2. Overview of Process Parameters for Optimization 3. Typical Scope of Supply for Skid Systems 4. Typical Applications for Biotech Centrifuges 28

29 ENZYMES flowsheet - Extracellular 29

30 VACCINES flowsheet 30

31 CSE 170 SIP-Package unit 31

32 1. Introduction to Sedimentation Centrifugation Principles & Design 2. Overview of Process Parameters for Optimization 3. Typical Scope of Supply for Skid Systems 4. Typical Applications for Biotech Centrifuges 5. CIP Approach 32

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