PTT303 /2
PROCESS MODELLING AND
SIMULATION
SEM 1 (2013/2014)
Biochemical Case Study
Student should be able to;
 Develop chromatographic process to achieve the
desired final product purity, combination with
membrane filtration to exchange buffers and
concentrate the dilute product solutions.
 Create the process and identify uncertainty problem
that might happen during the operations.
OUTLINE FOR BIOCHEMICAL
CASE STUDY
 A sequential modular approach to solve for a
moderate complex flowsheet
 Some common unit operations in biochemical
industries:
Fermenter
Disk-stack centrifugation
Diafiltration
Chromatography
Part 1
Fermentation
Section
Part 3
Purification
Section 2
Sequential modular approach
Part 2
Purification
Section 1
PROCESS DESCRIPTION
Water, microorganisms, nutrients (glucose)
and air are fed into a bioreactor where at
37°C a fermentation takes place, yielding an
enzyme and impurities. Biomass is separated
in a disk-stack centrifuge and the liquid is
stored in tank. It is then processed in a
diafilter where the remaining biomass is
removed (with a small loss of product). It is
stored again and then loaded onto a PBA
chromatography column where the enzyme
binds and eluted using a WFI/NaCl mixture.
PROCESS DESCRIPTION
Part 1
Fermentation Section
Fermentation
Unit
Bioreactor
Feed
•Water
•Microorganism
•Nutrients (glucose)
•air
Condition
37 °C
Output (yield)
Enzyme + Impurities
separated in a disk-stack
centrifuge and the liquid is stored in
tank. (storage 1)
Biomass
Part 2
Purification Section1
Diafiltration
Remove remaining
Biomass
Blending/ Storage
Store product
(small loss of product)
PBA
Chromatography
Column
Bind the enzyme
And eluted by using
WFI/NaCl mixture
Blending/ Storage
Store product
Part 3
Purification Section 2
Part 1
Fermentation Section
 Mode of operation: batch processing
 Component registration:
Glucose
Biomass
CO2
WFI (water for injection)
Enzyme (new-water as reference comp.)
Impurities ( new-water as reference comp.)
Process Flowsheeting for
Fermentation Section
UNIT
PROCEDURE
EQUIPMENT
DESCRIPTION
Fermentation
Vessel Procedure/ In
a Fermentor
transformation of raw
material into enzyme
& impurities
Centrifugation
Centrifugation/ Disk- separation of biomass
Stack
Storage/ Bulk/ Batch/ temporary product
in a Blending Tank)
storage
Rename as: Storage 1
(Right click
equipment/ Edit
labels)
Storage 1
PRODUCT
INITIALISATION FOR
FERMENTATION
SECTION
Fermentation
Centifugation
Storage 1
FERMENTATION
Initialising CHARGE operation
(right click on unit procedure (Fermentation)then click add /remove operations..
Add Charge -1, Charge-2, Heat-1, Ferment-1, Transfer-Out-1.
Continue…
CHARGE OPERATION
DATA
CHARGE-1
Charge 10000 L of water @ 100 L/min
CHARGE-2
Charge 1000kg glucose @ 40kg/min
HEAT-1
Final temp :37 °C
Efficiency: 90%
Duration: calculated based on constant heating
rate 0.5 °c/min
TRANSFER-OUT-1
duration same as Centrifugation
(use Master-Slave relationship)
Continue…
CHARGE
OPERATION
Ferment-1
(Stoichiometric)
DATA
Operation condition:
Final temp: 37 °C
Heat transfer agent: Cooling water
Process time: 36 hrs
Fermentor aeration: select air from stock mixture
(auto adjust)
Reaction (mass stoichiometry);
100Glucose + 80 O2
55 Water + 2 Enzyme +
3 Impurities + 80 CO2 +
40 Biomass
Reaction extent: 98% based on limiting component
Enthalpy: -3700 kcal/kg; ref. comp.: O2; ref. temp:37 °C
Emission: 100% for CO2 (select “Perform emission
calculation” & “Set By User” for CO2)
Note: Leave other values as DEFAULT
FERMENT-1
Final temp: 37 °C
Process time: 36 hr
Reaction extent
Enthalpy
data
Aeration setting:
Auto adjust for air
(stock mixture)
Mass stoichiometry
CENTRIFUGATION
UNIT
PROCEDURE
OPERATING
CONDITION
CENTRIFUGE-1 Equipment
design based on:
(default)
Solid Removal
Duration: 3 hr
(Centrifugation
time)
MATERIAL
BALANCE
Component
removal %: set
by User
UTILITIES
Exist temp:
15 °C (Set by
User)
Solid component Agent:
removal %: 98% chilled water
for biomass; 0%
for others
Solids
Concentration in
Solid Streams:
500 g/L
SCHEDULING
Start when
Transfer-out of
Fermentation
(P-1) starts
STORAGE 1
CHARGE
OPERATION
DATA
TRANSFER-IN-1: Operating conditions:
Transfer in using: outlet stream from
centrifuge
Duration: same as Centrifuge (set by MasterSlave Relationship)
STORAGE 1
Scheduling: Start when Centrifugation (P-2) starts
operation
Duration: to be determined
Scheduling: start when TRANSFER-IN-1 starts
Let’s simulate the
flowsheet & solve
the error message given
(scheduling problem)
PURIFICATION SECTION 1
Right click on storage; then click on add/remove operations/delete storage/add TRANSFER-OUT-1
Please delete “STORE-1”
operation in P-3 & replace
it with a “Transfer-Out-1”
Process Flowsheeting for
Purification Section 1
UNIT
PROCEDURE
Diafiltration (DF)
EQUIPMENT
Filtration/
Diafiltration
DESCRIPTION
Removal of all leftover biomass
from Storage 1
Remark: Storage (P-3) outlet needs
to be deleted before new stream
can be connected to the diafilter
Product Storage 2
Storage/ Bulk/
Batch/ In a
Blending Tank
Rename as:
Storage 2
(Note; Right click on equipment & select “Flip
(reverse direction)” to turn the equipment into
reverse direction
Temporary product stage
PROCESS DESCRIPTION ; Diafiltration
recycle
Feed tank
 In diafiltration, water or some other
solvent or buffer is added to the retentate
to facilitate the removal of membranepermeating species along with the water
(or other solvent) during filtration.
 The addition of water (or any other
solvent) can be conducted either in batch
or continuous mode.
In batch operation, permeable solutes are:
Cleared from the retentate by volume reduction (batch
concentration);
Followed by re-dilution with water ( or other solvent); and
Re-concentration in repetitive steps
Diafiltration in SuperPro
 In the current version of SuperPro
Designer, batch concentration can
precede and follow a continuous
operation (true diafiltration)
 Any number of batch concentration
stages can be specified for each
discontinuous operation.
 In general, if the initial solution is
dilute, a concentration step (to reduce
the volume of the material) usually
precedes a continuous diafiltration step.

Retentate
(Concentrate)
Feed
tank
Recycle Loop
If the initial solution concentration is rather high, one usually
goes directly to continuous diafiltration
Permeate
(Filtrate)
PRODUCT
INITIALISATION FOR
PURIFICATION
SECTION-1
Diafiltration
Storage 2
DIAFILTRATION
UNIT
PROCEDURE
DIAFILTER-1
(diafiltration)
OPERATING CONDITION
Rejection coefficient (RC): biomass
100%, impurities 20%, enzyme 5%
Max. solid concentration in retentate:
600 g/L
Product denaturation (denaturation is
due to shear forces during membrane
filtration, common in bioprocessing):
Denaturation: 4%
Active product: enzyme
Denaturated product: impurities
Duration: 4 hrs (filtration time)
Diluant: water (auto adjust)
Diafiltration data: 5 (Volume
Permeated)
Concentration data:
Prefiltration: YES, # of conc. stages: 1,
Conc. Factor 5
Postfiltration: NO
UTILITIES
SCHEDULING
Select “set by User”
Start with
TRANSFER-OUT
of Storage 1
Exit temperature =
15°C
Agent: Glycol
Specific power: 0.2
kW/m2
Continue…..
Additional task:
Set TRANSFER-OUT-1 of
Storage1 (P-3) to follow the
duration of Filtration inDiafilter
(P-4) using Master-Slave
relationship
STORAGE 2
UNIT
PROCEDURE
OPERATING CONDITION
SCHEDULING
TRANSFER-IN-1 Transfer in using: outlet stream from
DF (P-4)
Start (scheduling)
and duration
(Operating
condition: MasterSlave) same as DF
STORAGE 2
Scheduling: start
when TRANSFERIN-1 starts
Duration: to be determined
Simulate the Flowsheet
&
Solve The
Scheduling Error
PURIFICATION SECTION 2
Again, replace “STORE
-1” operation in P-5 with
“TRANSFER-OUT-1”
Process Flowsheeting for
Purification Section 2
UNIT
PROCEDURE
EQUIPMENT
DESCRIPTION
PBA
Chromatography
Equipment:
Chromatography/
Adsorption/ PBA
Chromatography
Description: binds and is elutes
the enzyme using a WFI/ NaCl
mixture (new mixture to be
registered
Product Storage 3
Storage/ Batch/ In a
Blending Tank
temporary product storage
Rename as: Storage 3
(Note: Right click on equipment & select “Flip (reverse
direction)” to turn the equipment into reverse direction
NEW MIXTURE REGISTRATION
We need a mixture of “NaCl/WFI(2M)” for this
section, but this mixture is not found in the
component database of SuperPro (verify this from
Stock Mixture database)
2 ways of registering this mixture:
 A) MODIFY FROM EXISTING MIXTURE
‘Register as NaCl (2M) & replace the water compound in
this mixture with WFI’
 B) REGISTER FROM SCRATCH
Register it from scratch & fill in the physical properties that
you have
A)MODIFY FROM EXISTING
MIXTURE
 Path: Task/Edit Stock Mixtures
Make sure the
mass % is make
up into 100%
Highlight the water
component, delete &
replace it with WFI
B)REGISTER FROM SCRATCH
Path: Task/Edit stock Mixtures
Create new mixture
Choose this option if
you know the density
of the mixture
Choose this option to modify from
an existing mixture (e.g. NaCl
mixture)
Let’s try it …
(Always remember to save your work …)
PRODUCT
INITIALISATION FOR
PURIFICATION
SECTION 2
PBA Chromatography
Storage 3
GENERAL DESCRIPTION :
PBA CHROMATOGRAPHY
4 different PBA
Chromatography
Column;
1)Column Loading (Load)
2)Column Washing (Wash)
3)Column Elution (Elute)
4)Column Regeneration
(Regenerate)
Regenerate
COLUMN
DESCRIPTION
PBA column loading (Load)
Estimate the time for loading a column, track
recovery yield, & estimate the number and size of
columns required
Column washing (Wash)
Wash away the undesired impurities that trap in the
column
A column may be used to bind either:
Product component(s); or
Impurity components
Column elution (Elute)
For retention of product components, for a
component that binds to the resin, its amount in the
product stream = (amount in the feed stream) x
(binding fraction) x (elution yield)
Colum regeneration
(Regenerate)
All component present in the feed stream, that do
not bind to resin, exit into the waste stream
Regenerate the resin using a solution
CHARGE
OPERATION
LOAD-1
OPERATING
CONDITION
Loading flowrate:
200 cm/h (linear velocity)
Resin’s primary function:
Retain Product (default)
Comp binding & yield;
-enzyme 100%, 90%
-impurity: 20 %, 30%
Info;
Binding refers to all
components that bind to
the resin;
Yield represents the
percentage of bound
material that ends up in
the product stream.
SCHEDULING
Starts when
Transfer-Out of
Storage 2
ADDITIONAL
TASK
For Storage 2:
Make sure that the
“Storage-1” operation
in Storage 2 is
replaced by
“TRANSFER-OUT1”
Set TRANSFEROUT-1 of Storage 2
to have the same
duration as LOAD-1
using Master-Slave
Relationship
CHARGE
OPERATION
WASH-1
OPERATING
CONDITION
•Volume per cycle: 2 BV (bed volumes)
•Wash stream: “Wash” stream which
contains WFI (auto adjust)
ELUTE-1
REGENERATE-1:
•Eluant Volume:
Total Volume: 8 bed vol.
Volume in Product Stream: 2 bed vol
•Flow rate Options: 200 cm/h (linear
velocity)
•Elution Strategy: Gradient
•Key comp data:
Name: NaCl
Initial concentration: 0 mol/L
Final concentration: 1 mol/L
•Eluant A: NaCl/WFI (2M) in stock mixture
•Eluant B: WFI (auto-adjust)
•Linear velocity: 300 cm/h
•Volume per Cycle: 2 BV
•Wash stream: “Regen” stream with WFI
(auto-adjust
ADDITIONAL
TASK
Additional task: Delete
“Equilibrate” operation
in P-6
STORAGE 3
CHARGE
OPERATION
DATA
SCHEDULING
TRANSFERIN-1:
Transfer from: PBA
chromatography; using
outlet stream from PBA
chromatography
Start (scheduling) and duration
(Operating condition: Master-Slave)
same as ELUTE-1 in PBA
chromatography (Q: why not the last
operation?)
TRANSFEROUT-1:
Transfer to: none; using
Start when TRANSFER-IN-1
outlet stream from Storage completed
3
Check your simulation results
Check the input to your PBA chromatography
Since we specify comp binding & yield for:
Enzyme to be 100%, 90%
Impurity: 20%, 30%
The amount of enzyme in the product stream: ___kg
The amount of impurities in the product stream
should be: ___kg
•Please check this out & verify this from your
simulation results.
Biochemical Case Study REPORT
Prepare a detail report of the BIOCHEMICAL
CASE STUDY and attached together
your simulation result (Gantt Chart)