OSCILLATORY FLOW BIOREACTOR FOR BIO- PROCESSING WITH LOW TEMPERATURE HEAT SUPPLY

Transcription

1 OSCILLATORY FLOW BIOREACTOR FOR BIO- PROCESSING WITH LOW TEMPERATURE HEAT SUPPLY Oscillatory Flow Bioreactor (OFB) Bettina Muster, Judith Buchmaier, Christoph Brunner AEE Institut für Nachhaltige Technologien (AEE INTEC) 8200 Gleisdorf, Feldgasse 19, Österreich AEE INSTITUT FÜR AEE NACHHALTIGE INSTITUTE FOR TECHNOLOGIEN SUSTAINABLE TECHNOLOGIES

2 Content Introduction / Background Status Quo: Challenges in bio-slurry treatment Approach: Oscillatory Baffled Reactor Realization: Lab Plant Design, Experimental Results Summary & Outlook

3 New Technologies and low temperature heat supply Emerging technologies facilitate solar integration Some intensification strategies have direct impact on solar heat supply: heat transfer enhancment From batch to continuous Increasing selectivity in separation processes Intensification by electrohydrodynamics

4 Continuous processing (vs. batch) High process efficiency small residence time distribution, structured processes Good process controllability Low energy intensity (no peaks in heating/cooling demand) Low cleaning requirements Flexible processes Decreased energy distribution losses due to continuous heat demand Increased safety due to less storage of hazardous chemicals

5 Continuous mashing? Optimized mashing schedules For better integration of low temperature heat supply (solar) > 50% reduction in load peaks potential for continuous process Continuous reactor with min residence time? Muster-Slawitsch, B., et al., Process modelling and technology evaluation in brewing, Chemical Engineering and Processing: Process Intensification 84, (2014).

6 State of the art in bio-processing Water Enzymes Starch / (Ligno-) Cellulose Hydrolysis Sugar X

7 State of the Art vs. Innovative Reactor Concept State of the Art: Stirred Tank Reactor - Batch Water Enzymes Sugar Innovation: Oscillating Baffled Reactor- Continious Water Enzymes Sugar

8 Status Quo Stirred Tank Reactor STR + simple, well established + long residence times for slow reactions but: inadequate mixing non-structured media flow - problems in process monitoring and control (significant ph and temperature gradients) - wide residence time distribution STR = non-ideal apparatus when product inhibition occurs Quelle: istock

9 Approach: Oscillatory Baffled Reactor develop a continuous enzymatic hydrolysis process with plug-flow -effects on conversion rates and -reduction in enzyme addition. Oscillating Flow Bioreactor - OFB. For: -biobased industry -chemical industry -biodiesel production -pulp and paper industry decoupling flow velocity and residence time Quelle:

10 New reactor design for process intensification in biobased industry Sigma Aldrich Anton Paar Pure Alpha Cellulose OFB Hydrolysis Glucose Measurement OFB vs STR Comparison Oscillating Flow Bioreactor -Batch & (Semi) Continious Mode Objectives: high conversion rate (glucose production over time) reduction of enzyme Low power requirement (W/m³)

11 Realization: Pre-Tests, Lab Plant Design, Lab Plant Experiments 4 weeks pre tests at University of Newcastle Lab-Plant Design Lab-Plant Experiments

12 Flow Behaviour: Plug Flow Demonstration- Ink Exp. Flow direction

13 Mixing Quality: Glucose / Cellulose Distribution along reactor length Measurement: filter paper, dry content measurement Measurement: analysis procedure based on DMA 35 from Anton Paar

14 Oscillation power requirement [W] Power Consumption: Influence of Viscocity > Power requirement for oscillation interestingly does not correlate with feed viscosity, allowing the treatment of viscous slurries at low energy intensity. Effect on [W] at diff. Viscocities Hz 3.5 Hz 5 Hz Air Water 10% cell 15% cell. 5% Ligno-cell.

15 Power Consumption [W] Power Consumption: 12 % α-cellulose at varying frequencies > Linear increase in power consumption at higher frequencies. > Higher amplitudes: positive effect on mixing, negligible effect on power consumption. 12% α-cellulose, 50 C, 10 mm ampl., 10 FPU/g 80 cm reactor, 25,5 mm ϴ, 3mm Helix y = 13,838x + 55,056 R² = 0, ,5 2 2,5 3 3,5 4 4,5 5 Frequency [hz]

16 Oscillation power requirement [W] Effect of Reactor Lenght on Power Requirement Effect of Reactor Lenght 180,00 160,00 140,00 120,00 100,00 80,00 60,00 40,00 20,00 0,00 1 Hz 3,5 Hz 5 Hz 10% cellulose, 10mm osc. ampl.

17 Influence on heat transfer coefficients oscillatory mixing increases the radial transport of the fluid within the reactor increasing heat transfer coefficients, for the same net flow Reynolds numbers

18 Glucose Formation over 24 hours Comparison of STR and OFB performance at different energy intensities (W/m³)

19 Conclusions / Results comparable (STR vs OFB) conversion could be achieved for 12% and 15% SL, where mixing of the OFB module outperforms the STR mixing efficiency. The OFB system operated at 3,5 Hz and 10 mm oscillation amplitude shows similar conversion efficiency when operating at only 12 % of the STR s energy intensity W/m³. Heat transfer coefficients in batch system increased, due to higher radial mixing High Potential of OFB System for high solid loading, at low energy intensities.

20 Outlook - Optimization of the system in terms of temperature profile, measurement points, sample ports - Continuous tests: to overcome the effects of product inhibition in batch reactors. - Further applications: biomass fractionation, different types of biomass; particle sizes; pretreatment methods.

21 Thanks to the funding agency and project consortium

22 Thanks for your attention!