TOWARDS SUSTAINABLE AND EFFICIENT BIOFUELS PRODUCTION – USE OF PERVAPORATION IN PRODUCT RECOVERY AND

SEPARATION

POKE Summer School 10.–16.8.2014Saaremaa, Estonia

D.Sc.(Tech.) Johanna Niemistö

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August 2014FACULTY OF TECHNOLOGY / Environmental Engineering

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DOCTORAL THESIS

I. García V, Päkkilä J, Ojamo H, Muurinen E & Keiski RL (2011) Challenges in biobutanol production: How to improve the efficiency? Renewable and Sustainable Energy Reviews 15(2): 964–980.

II. Niemistö J, Saavalainen P, Isomäki R, Kolli T, Huuhtanen M & Keiski RL (2013) Biobutanol production from biomass. In: Gupta VK & Tuohy MG (eds) Biofuel Technologies: Recent developments. Berlin-Heidelberg, Springer-Verlag: 443–470.

III. Niemistö J, Saavalainen P, Pongrácz E & Keiski RL (2013) Biobutanol as a potential sustainable biofuel - Assessment of lignocellulosic and waste-based feedstock. Journal of Sustainable Development of Energy, Water and Environment Systems 1(2): 58–77.

IV. Niemistö J, Kujawski W & Keiski RL (2013) Pervaporationperformance of composite poly(dimethyl siloxane) membrane for butanol recovery from model solutions. Journal of Membrane Science 434: 55–64.

V. Niemistö J, Pasanen A, Hirvelä K, Myllykoski L, Muurinen E & Keiski RL (2013) Pilot study of bioethanol dehydration with polyvinyl alcohol membranes. Journal of Membrane Science 447: 119–127.

Public defence28.3.2014

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

http://jultika.oulu.fi/Record/isbn978-952-62-0388 -1

INTRODUCTION 3

• Production and use of biomass-based biofuels and chemicalshave been increasing strongly during the 21st century

• Bioethanol and biodiesel are currently the most used liquidtransportation biofuels Alternative biofuels are also needed to fulfill the increasing

demand in the future Biobutanol has superior fuel properties over ethanol

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

Figure from Renewables 2013 Global status report (REN21 (2013), p. 30)

THE AIM OF THIS WORK

• To gain new knowledge on the production of transportation biofuels (biobutanol and bioethanol)

• To point out the main challenges and bottlenecks in the present production processes

• To increase sustainability and process efficiency of production steps, e.g. by using enhanced processing techniques and improving the efficiency in energy and material usage

• To evaluate the feasibility of pervaporation as the product separation method for the recovery and purification of bioethanol and biobutanol, and other solvents after the fermentation step

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FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

THE CONTENTOF THESIS

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FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

Biobutanol production process: Papers I and II

• Superior fuel properties of butanol as comparedto ethanol

• Challenges in the processing• Overview of the used processing techniques and

recent improvements• Biorefinery perspective and resource efficiency

Sustainability assessment offeedstocks for biobutanol production:

Paper IIIBioethanol dehydration by

pervaporation: Paper V

• Feasibility study for thepervaporative bioethanoldehydration

• Pretreatment of bulk bioethanolby activated carbon filtration

Solvent recovery from aqueoussolutions by pervaporation:

Paper IV

• Permeation performance study for the removal of n-butanol, acetone and ethanol from aqueous model solutions

Towards sustainable and efficient biofuels

production – use of pervaporation in product recovery and purification

• European legislation and sustainability criteria

• Sustainability assessment of fourfeedstock sources

PRODUCTION OF TRANSPORTATION BIOFUELS (FERMENTATION PROCESS), PAPERS I AND II

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LignocellulosicsAgricultural residuesCrop biomassesMunicipal solid wasteNon-food biomassesIndustrial by-products

Pretreatment methodsBiologicalChemicalPhysicalPhysico-chemical

HydrolysisEnzymaticDilute acidConcentrated acid

Batch Fed-BatchContinuousExtractiveFlash Immobilized cellsSimultaneously saccharification & fermentation (SSF) Two-stageFermentation byusing E.colior other microorganisms

AdsorptionDistillationGas strippingLiquid-liquid -extraction

PerstractionPervaporationReverse osmosis

DetoxificationAdsorptionEnzymatic EvaporationExtractionIon exchange resins

Overliming

ProductsAcetoneButanolEthanolAcetic acidButyric acidCO2H2

Feedstocks

Downstream processing

Upstream processing

Fermentation

Sugar rich biomassSugar beatSugar cane Whey permeate

Starch rich biomassGrainsPotato

Acetone-Butanol-Ethanol(ABE) -process• Clostridium bacteria• A:B:E ratio ≈ 3:6:1

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

PROCESS INTENSIFICATION

• Challenges Cost of substrates and unit processes

• final cost of a product depends usually strongly on the efficiencies of the separation and purification steps

Product inhibition • low product concentrations, low yield

Complex process chain

• Solutions Novel processing techniques Hybrid processes Biorefineries: combined production of fuels, value-added

chemicals, power, heat, etc.

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FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

SUSTAINABILITY OF BIOFUELS PRODUCTION• Sustainability assessment in relation to biofuels production focuses

mainly on land use and GHG emissions All sustainability aspects should be taken into account including

environmental, economic and social impacts

• Selection of proper indicators and measurement tools for impact evaluation is challenging

Harmonization and common criteria are needed

Figure: http://www.sustainability.umd.edu/content/about/what_is_sustainability.php

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

SUSTAINABILITY ASSESSMENT OF FEEDSTOCKS FOR BIOBUTANOL PRODUCTION, PAPER III

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Economic impacts Environmental impacts Social impacts

Feedstock price Biodiversity and land use change Customer acceptance and social dialog

Processing costs Hazardous and toxic material usage Ethicality and competing demand of rawmaterials

Value added Emissions (e.g. GHG) Employment effects

Energy Health and safety issues

Wastes vs. by-products Innovation and education potential

Water consumption

Indicators chosen for biobutanol feedstock evaluation:

Crop biomass:corn

Non-edible crop: straw

Food by-product: whey

Wood-based biomass:saw dust

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

PRINCIPLE OF PERVAPORATION10

Feed side (liquid phase)

Permeate side(gas phase)

₀ More permeable compound

• Less permeable compound

① Sorption ② Diffusion③ Desorption

① ② ③

Feed

Retentate Permeate

μf > μpPf > Pp

• •• ₒ •

•ₒ • ₒ •

• • • • ₒ

• • ₒ • • •

• • ₒ ₒ • ₒ

• • •

ₒₒ • ₒ

ₒ • ₒₒ •

membrane

Bulk feed Boundary layer

Concentration

Temperature

Porous support layer

Non-porous selective layer

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

PERVAPORATION11

Some potential applications: Removal of organic compounds from aqueous systems (separation of

products/inhibitors/valuable compounds from fermentation broths) Dehydration of organic solvents (azeotropic mixtures)

Case-specific selection of the best techniques for each process

Advantages Disadvantages+ No additional chemicals needed - Membrane swelling

+ More energy efficient than conventional distillation

- Temperature and concentration polarization

+ Simple, compact, flexible and versatile

- Membrane fouling

+ High selectivity also in lower operating conditions

- More or less tailor-made membranesneeded for different applications

+ Can be combined to hybrid systems - Industrial scale applications may be difficult to achieve

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

PERVAPORATION EXPERIMENTS, PAPERS IV AND V

ABE-process Ethanol process

Targetcompound

Acetone, butanol and ethanol Water

Membrane Hydrophobic PDMS-PAN Hydrophilic PVA

Membrane area 170 cm2 1 and 2 m2

Feed solution Around 3 litres,solvent concentration below5 wt%

35 and 70 kg, ethanolconcentration ~85 99.6 wt%

Temperature 42 °C 98 °C

Other remarks Different binary, ternary and quaternary model feedsolutions used

Activated carbon filtration wasused as pretreatment before thepervaporation

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FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

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Sampling Analysis of samples (e.g. by gas chromatography) Determination of separation performance:

• Flux• Selectivity• Separation factor• Pervaporation Separation

Index (PSI)

1) Heating unit, 2) Feed tank, 3) Feed sampling, 4) Circulation pump,5) Membrane unit, 6) Cold traps, 7) Vacuum pump

PERVAPORATION EXPERIMENTS

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

BUTANOL RECOVERY14

Membrane permselectivity followed the order ofacetone≈n-butanol>ethanol

Separation of ethanol was much lower as compared to acetone and n-butanol

Permeation of n-butanol is preferable in solutions containing several organic compounds, indicating that the tested PDMS-membrane has a potential to be used in the ABE fermentation process.

Niemistö J., Kuawski W., Keiski R.L. (2013), Pervaporation performance of composite poly(dimethyl siloxane) membrane for butanolrecovery from model solutions. Journal of Membrane Science, 434:55–64.

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

CONCLUSIONS 15

Figure: Harvey B.G. & Meylemans H.A. (2011),J. Chem. Technol. Biotechnol. 86: 2–9

Demand of biofuels and biochemicalsproduced from renewable raw materials is increasing continuously

Production processes should be• technically feasible• economic• sustainable in economic, environmental and

social matters

Separation processes especially have an important role in chemical industry and in biorefineries

Results of this thesis show that pervaporationcan be used as a separation method in biofuels production processes

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

ACKNOWLEDGEMENTS 16

• The Academy of Finland• The Finnish Funding Agency for Technology and Innovation (Tekes)• St1 Biofuels Oy, Sulzer Chemtech Ltd.

• Doctoral Program in Energy Efficiency and Systems (EES)• Graduate School in Chemical Engineering (GSCE)

• Oulun läänin talousseuran maataloussäätiö• Tauno Tönning foundation• Riitta and Jorma J. Takanen foundation

• Research group of Mass and Heat Transfer Processes• Research group of Professor Kujawski (Nicolaus Copernicus University,

Poland)• Family and friends

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

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THANK YOU!

FACULTY OF TECHNOLOGY / Mass and Heat Transfer Process Engineering / Johanna Niemistö

THANK YOU FOR YOUR ATTENTION!