Industrialisation of synthetic biology Flashcards
Bioreactor Parts
- air inlet
- impellor motor
- antifoam to remove foam physically/chemically + antifoam sensor
Bioreactor Variables
Control Variable
- impellor speed
- air flow rate
Fixed Variable
- Temp
- pH
- medium addition rate
Scale-up
- Definition : Study of problems associated with the transfer of experimental data from laboratory to pilot or commercial-scale equipment.
- Objective : To set-up Agitation and Aeration in the larger scale bioreactor in order to reproduce the performance which was optimized in the lab-scale
Approaches
Numbering Up
- more resources required
Direct Optimisation
- resource-intensive
Mass Transfer Rate Constant
- efficient
Direct Optimisation
- For 100,000L culture, a series of seed cultures required (with inoculum size of 2-5%(v/v))
- Each seed culture takes ~2 days including medium preparation, sterilization and washing
- Tot 111,111L of culture medium required
- at least 9 experimental operations required for optimization
(low, medium, high condition for each aeration and agitation)
Mass Transfer Rate
KLa (s-1) : volumetric mass transfer coefficient
C* : O2 saturation concentration (mg O2/L)
CL : measured O2 concentration in the liquid phase (mg O2/L)
Oxygen transfer rate (OTR) = KLa x (C* – CL)
In order to obtain the same fermentation performance, (OTR)1 = (OTR)2
- (KLa)1 = (KLa)2
- Need to find agitation 2 and aeration 2 where the (KLa)2 = (KLa)1
- Calculate (KLa)2
- (KLa)1 = (KLa)2 ?
- obtain rpm/vvm
1,3-PRopanediol
BioPDO
Replace chemical process
(EO → 1,3-PDO by Shell)
40% less energy
20% less greenhouse gas
15 yr, $130M , 60,000ton/yr
- use PTA(Purified terephthalic acid) to convert to PTT(Polytrimethylene terephthalic acid) fibres
First Step of PDO production
- convert corn to sugar
- liquefication : amylase hydrolyses macromolecular amylopectin and amylose into dextrin mixture
- saccharification : enzymes degrade gelatinised starch and dextrins into fermantable sugars, converted to alchohol; glucoamylase acts in a-1,4, a-1,6, and a-1,3 branch bonds
2nd step of PDO production
- Sugar to PDO
- in nature, 2 microorganisms convert stepwise, but biotech uses single microorganism(engineered e. coli via extending yeast pathway to glyerol with Klebsiella pathway extesion)
- purification via microfiltration, ultrafiltration, ion exchange, flash evaporation, distillation, and hydrogenation
Other bio-based fuels and chemicals
Sugarcane -> ethanol -> Bio-PET
Corn -> glucose - > PBS 1,4 butanediol
Veg oils -> glycerol -> propylene glycol(absorbantt matherial)
Ligocellulose -> ethanol
