1. Chemical Reaction Engineering (CRE) is the field that studies the rates and mechanisms of chemical reactions and the design of the reactors in which they take place. Lecture 16

2. Bioreactors Monod Equation Yield Coefficients Washout 2 Web Lecture 16 Class Lecture 25 – Thursday 4/18/2013

3. 3 Enzymes - Urease A given enzyme can only catalyze only one reaction. Urea is decomposed by the enzyme urease, as shown below. The corresponding mechanism is: Review Last Lecture Michaelis Menten Equation

4. Bioreactors 4 Nutrient (S) + + Products cells more cells

5. Bioreactors 5

6. Batch Bioreactor 6

7. Phases of Cell Growth and Division 7

8. inoculum t=0 time  8 Cells + Substrate  More Cells + Product Bioreactors

9. 9 Exponential Growth Phase Death Phase Stationary Phase Lag Phase 0 time lnC c a)Phases of bacteria growth: I. LagII. ExponentialIII. StationaryIV. Death b) Monod growth rate law: Bioreactors

10. 10 1) Mass Balances Accumulation = [In] - [Out] + [Growth] - [Death]

11. Rate Laws: C p *= Product concentration at which all metabolism ceases 11 Bioreactors

12. 3) Stoichiometry A) Yield Coefficients B) Maintenance 12 Bioreactors

13. 13 3) Stoichiometry Rate of Substrate Consumption Can’t separate substrate consumption used for cell growth from that used for product formations during exponenial growth. Bioreactors

14. v 0 C S0 V=V 0 vCCCSvCCCSC Volume=V 14 1) Mass Balance: Bioreactors

15. 15 Bioreactors

16. 2) Rate Laws: 3) Parameters 16 Bioreactors

17. 1.) d(C C )/d(t)=-D*C C +(r g -r d ) 2.) d(C S )/d(t)=-D*(C S0 -C S )-Y sg *r g -m*C C 3.) d(C P )/d(t)=-D*C P +Y PC *r g 4.) rg=(((1-(C P /C pstar ))**0.52)*mumax*(C S /(K S +C S ))*C C 5.) D=0.2 6.) k d =0.01 7.) r d =k d *C C 8.) C S0 =250 9.) Y PC =5.6 10.) m=0.3 11.) mumax=0.33 12.) Y SC =12.5 13.) K S =1.7 Polymath Setup 17

18. Bioreactors – Chemostats - CSTRs 18 1. Steady State - Neglect Death Rate and Cell Maintenance 2. Cell

19. 3. Substrate 19 Bioreactors – Chemostats - CSTRs

20. CSTR Washout C DWDW DC 20 Washout dilution rate Bioreactors – Chemostats - CSTRs

21. Maximum Product Flow Rate 21 How does this figure relate to drinking a lot of fluids when you have an infection or cold? DC C DWDW D D maxpro d

22. End of Web Lecture 16 End of Class Lecture 25 22