Pengendalian Bioproses

Transkripsi

1 Your logo Bioprocess Engineering Control - Spring 2013/ Pengendalian Bioproses Sistem pengendalian dan modifikasi pada bioreaktor pada berbagai tipe bioreaktor Dina Wahyu Indriani Keteknikan Pertanian- Mei 2013

2 Materi Kuliah Jadwal dan materi No Materi Submateri Waktu Mengetahui pengendalian bioproses dalam berbagai macam aplikasi/ penelitian Sistem Pengendalian konsentrasi pada bioreaktor fermentasi (2) Sistem pengendalian pada bioreaktor pada berbagai tipe bioreaktor 11 Resume dan Persiapan Presentasi Sistem Pengendalian Chemical Compund, Multistage Chemostat Systems. Sistem Pengendalian dalam aliran (Group Presentation) Contoh-contoh pengendalian dalam Bioproses Konsep Pengendalian pada sistem fermentasi Pemodelan pengendalian pada Bioreaktor fermentasi Contoh aplikasi pengendalian konsentrasi, suhu dan ph dalam penelitian Sistem pengendalian dalam mengetahui jumlah bakteri, Total Organic Compund, dalam bioreaktor fermentasi Pengendalian aliran dalam bioreaktor fermentasi April (3) April (4) May (1) May (2) May (3) May (4) 14 Presentasi Paper (Group Presentation) May (5) Page 2

3 INTRODUCTION These chapters should give the reader an understanding of how real bioprocesses can be assembled. An important decision for constructing any process concerns the configuration the reactor system should take. Thus, our choice of reactor must be made in the context of the total process: biocatalyst, reactor, and separation and purification train.

4 CHOOSING THE CULTIVATION METHOD (1/4) One of the first decisions is whether to use a batch or continuous cultivation scheme. First, we can consider productivity. For a batch reactor, four distinct phases are present: lag phase, exponential growth phase, harvesting, and preparation for a new batch. (3.1) The total amount of cell mass produced comes from knowing the total amount of growth-extent-limiting nutrient present and its yield coefficient: (3.2)

5 CHOOSING THE CULTIVATION METHOD (2/4) The rate of cell mass production in one batch cycle (r b ) is (3.3) The value for D optimal when simple Monod kinetics apply is given by eq. 6.83, and the corresponding X can be determined to be (3.4) Thus, the best productivity that could be expected from-a chemostat where Monod kinetics apply is D opt X opt,or (3.5)

6 CHOOSING THE CULTIVATION METHOD (3/4) Under normal circumstances So» Ks so the rate of chemostat biomass production, r c is approximately The ratio for rate of biomass formation is (3.6) (3.7) We would expect continuous systems to always have a significant productivity advantage for primary products. The first is that eq. 3.7 applies only to growth associated products. Many secondary products are not made by growing cells; growth represses product formation.

7 CHOOSING THE CULTIVATION METHOD (4/4) Another primary reason for the choice of batch systems over chemostats is genetic instability. Another consideration is operability and reliability. One other factor determining reactor choice is market economics. Most bioprocesses are based on batch reactors. Continuous systems are used to make single-cell protein (SCP), and modified forms of continuous culture.

8 MODIFYING BATCH AND CONTINUOUS REACTORS Chemostat with Recycle (1/8) Figure 3.1.

9 MODIFYING BATCH AND CONTINUOUS REACTORS Chemostat with Recycle (2/8) Microbial conversions are autocatalytic, and the rate of conversion increases with cell concentration. Cell recycle increases the rate of conversion (or productivity) and also increases the stability of some systems (e.g., wastewater treatment) by minimizing the effects of process perturbation. A material balance on cell (biomass) concentration around the fermenter yields the following equation: (3.8) At steady state, and if dx 1 ldt = 0 and X 0 = 0 (that is, sterile feed); then eq. 9.8 becomes (3.9)

10 Chemostat with Recycle (3/8) Since C > 1 and α (1- C) < 0, then µ net < D. That is, a chemostat can be operated at dilution, rate higher then the specific growth rate when cell recycle is used. A material balance for-growth-limiting substrate around the fermenter yields (3.10)

11 Chemostat with Recycle (4/8) At steady state, ds/dt = 0 and (3.11) Substitution of, eq. 9.9 when k d = 0 into eq yields (3.12) The steady-state cell concentration in a chemostat is increased by a factor of 1/(1 + α - αc) by cell recycle.

12 Chemostat with Recycle (5/8) The substrate concentration in the effluent is determined from eq. 3.9 and the Monod eq, where endogenous metabolism is neglected, and is (3.13) Then eq, 3.12 becomes (3.14)

13 Chemostat with Recycle (6/8) Figure 9.2.

14 Chemostat with Recycle (7/8) Contoh Soal. Dalam sebuah chemostat dengan cell recycle dalam gambar 3.1, fed- flow rate F = 100 ml/h dan volume culture V = 1000 ml. Sistem beroperasi dalam pengaturan jumlah glukosa, dan Yield Coeficient Y x/sm is 0.5 gdw cells/g substrate. Konsentrasi Glukosa dalam keadaan steady state feed adalah S 0 = 10 g glukosa / L. Kinetik konstans dalam organism adalah µ net = 0.2 h -1, K s = 1 g glukosa / L. Nilai C adalah 1.5 dan ratio Recycle adalah alfa = 0.7. Sistem dalam keadaan steady state. a. Carilah kosentrasi substrate dalam recycle stream (S) b. Carilah Nilai Specifc Growth rate (µ net ) dalam organism c. Carilah Nilai Konsentrasi Cell (biomass) dalam recycle stream d. Carilah NIlai konsentrasi cell dalam Centrifuge Effluent (X 2 )

15 Bioprocess Control Application Page 15

16 Assignments Tugas Mingguan Pengumpulan Paper dan Naskah Resume Q5. Paper and Resume? Please submitted the assignments before next week, say 8 May. At class s leader Page 16

17 Rumusan Perkuliahan Pengendalian Bioproses Pengukuran dan pengendalian bioproses merupakan matakuliah terapan dari Elektronika dan Intrumentasi, Sistem Kontrol, Matetmatika Terapan, Fisika serta Kinia dasar. Sistem Pengendalian Bioproses lebih difokuskan kepada arahan dan bimbingan kepada mahasiswa yang akan melakukan pengendalian bioproses dalam penelitian sehingga dasar serta konsep pengendalian yang diajarkan dalam matakuliah ini teraplikasikan. Keteknikan Pertanian Fakultas Teknologi Pertanian Universitas Brawijaya Malang Join UB be The Best Selain itu sistem pengndalian yang terdapat dalam matakuliah ini merupakan sistem pengendalian yang difokuskan kepada bioproses. Sehingga mahasiswa dapat membedakan konsep proses dan bioproses. Page 17