Bioreactor Design Nur Istianah, ST.,MT.,M.Eng

TEKNOLOGI BIOPROSES

A continuous

stirred-tank reactor

(CSTR) is an ideal

reactor which is

based on the

assumption that

the reactants are

well mixed. Continuous

operation with

stirring

F, Cs0

F, Cs

V

Nur Istianah-THP-FTP-UB-2017

-3. Continuous stirred-tank

dt

dXVVrXXF x )( 0

F, Cs0

F, Cs

V

onAccumulati GOutput -Input eneration

Nur Istianah-THP-FTP-UB-2017

the ratio of biomass

rate of generation to

biomass

concentration, rx/X,

that is the specific

growth rate; μ X

rx

D

0dt

dX s

Steady state:

DV

F

1

00 XNo cell in

inlet:

D

XDX

rXXV

Fx

.

)( 0

-3. Continuous stirred-tank – cont.

Monod rate: ss

s

CK

C

max

ss

s

CK

CD

max

D

DKC s

s

max

maxmax

111

s

s

C

K

D

Chemostat:

Nur Istianah-THP-FTP-UB-2017

At steady state, substrate utilisation is balanced with a rate

equation:

VCK

CCCF

ss

s

ss

max

0 )(

XCK

CCCD

ss

s

ss

max

0 )(

CsCs

XXY

0

0

D

DKCYXX s

s

max

00

Case study

• Contoh soal 4:

• Kinetika Monod (Ks = 3 g/L) telah

dipertimbangkan dalam operasi CSTR untuk

memproduksi yeast dengan konsentrasi awal 50

g/L. Jika laju pertumbuhan yeast maksimal

sebesar 0.5 jam-1, berapakah laju dilusi

fermentasi untuk konversi reaksi sebesar 90% ?

asumsikan tidak ada yeast di awal fermentasi.

Solution

Cs = (1-XA)Cs0 = (1-0.9)( 50 g/L) = 5 g/L

1

1

max

3125.0

g/L5g/L3

g/L55.0

jamD

xjamD

CsK

CsD

s

Case study

• Contoh soal 5:

• Hitunglah laju dilusi dari contoh soal 4 jika

terdapat konsentrasi yeast di awal dan akhir

fermentasi sebesar 0.1 g/L dan 35 g/L!

Solution

• Pada kondisi ini berlaku persamaan berikut:

X

rx

xrXXD )( 0SK

S

s max

)(

)(

0

0

XX

XD

XX

rD x

1

0

max

3134.01.035

)35(3125.0

)(

jamD

XX

XSK

S

D s

Case study

• Contoh soal 6:

• Berapakah yield fermentor pada contoh soal 5?

–Solution:

%56.777756.0550

1.035

0

0

Y

SS

XXY

Solution

• Pada kondisi ini berlaku persamaan berikut:

X

rx

xrXXD )( 0SK

S

s max

)(

)(

0

0

XX

XD

XX

rD x

1

0

max

3134.01.035

)35(3125.0

)(

jamD

XX

XSK

S

D s

Case study 7 • A chemostat study was performed with east. The

medium flow rate was varied and the steady state

concentration of cells and glucose in ther fermenter were

measured and recorded. The inlet concentration of

glucose was set at 100 g/L. The volume of the fermenter

contents was 500 mL. the inlet stream was sterile.

• Find the rate equation of cell growth

Flow rate

F, mL/ hr

Cell concentration

Cx, g/ L

Substrate concentration

Cs, g/ L

31 5.97 0.5

50 5.94 1.0

71 5.88 2.0

91 5.76 4.0

200 0 100

Solution

• Pada kondisi ini berlaku persamaan berikut:

maxmax

111

s

s

C

K

DChemostat:

1/D = V/F 1/ Cs

16.13 2.00 10.00 1.00 7.04 0.50 5.49 0.25 2.50 0.01

y = 3.1764x + 1.2959 R² = 0.9407

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

0.01 0.25 0.50 1.00 2.00

78.0

13.1

max

max

46.2

2.3max

Ks

Ks

Persamaan laju reaksi

s

s

ss

s

C

XCr

CK

XCr

Xr

46.2

78.0

max

THANKS FOR YOUR ATTENTION

The best person is one give something useful always

Nur Istianah-THP-FTP-UB-2017