Prindi see leht

Bioenergy and Biofuels workgroup


Prof. Timo Kikas
Tel: (+372) 731 3163


Chair of Biosystems Engineering
Institute of Technology
Estonian University of Life Sciences
56 Fr. R. Kreutzwaldi
51006 Tartu, ESTONIA
At the moment there are two professors, two research fellows, a Marie Curie research fellow, a postdoctoral fellow, and eight doctoral students in our workgroup. Two main topics are headed by Professor Timo Kikas and Professor Erwan Rauwel. In last years, we have received two international grants, Marie Curie postdoctoral grant, a Mobilitas Pluss postdoctoral grant, and several national research grants. Our research group is also part of the Centre of Excellence EQUiTANT that studies emerging orders in quantum and nanomaterials.

The research of biofuels was started in the Institute of Technology in 2007 by Professor Jüri Olt. At first it focused mainly on the solid fuels, like briquettes and pellets. Briquetting characteristics and optimal conditions of different lignocellulosic materials and agricultural wastes were studied.

In 2008, research of liquid biofuels was added to the portfolio. First studies were on first generation feedstock and biofuels like bioethanol and vegetable oil. Later, research of second and third generation biofuels prevailed to avoid the ethical, economic and environmental problems associated with the first generation.

In 2011, a new workgroup was formed in the department Agricultural and production engineering, that started the research on bioethanol production from lignocellulosic biomass. The main focus was on the efficiency of the pretreatment process of the biomass and on the continuous process production.

In 2013, a novel Nitrogen Explosive Decompression (NED) pretreatment was developed. The NED allows efficient pretreatment of the lignocellulosic biomass without using any chemicals. This makes it environmentally and economically interesting. NED pretreatment makes use of the fact that nitrogen gas has different solubilities in water under different pressures.

During the same period laboratory of microalgal research was started. Microalgae have many characteristics that make them interesting research subjects and potential alternative biomass source. Firstly, microalgae have the most efficient photosynthesis apparatus on the planet. They can be used to sequestrate carbon dioxide both, from air and from flue gas. The biomass production rates for microalgae are many times higher than that of their land counterparts. Also, many of the microalgae have very high lipid contents. Which make them also potential raw material for lipid-based biofuels. There is also a novel photobioreactor design that has been patented in our laboratory.

In 2016, a research topic was started to deal with the waste utilisation of bioethanol production process. There is ca 20L of stillage produced per every litre of ethanol produced. This stillage has very high BOD and requires treatment prior to realising it into the environment. One interesting possibility is to use anaerobic digestion to remove the degradable organics from the solution while also contributing to additional energy output from the process.

In 2018, the workgroup was joined by Professor Erwan Rauwel and senior researcher Protima Rauwel, who brought into the group know-how in the field of nanotechnology. Their main research focuses on metal oxide (HfO2, ZrO2, ZnO) and metal nanoparticle (Co, Ag, Ag_Co…) synthesis for application in water purification (heavy metal ions and radioactive elements), biomedical applications (biocidal coating) and the development of new hybrid nanocomposites for photovoltaic applications.

In addition, workgroup got a Mobilitas Pluss grant for a postdoctoral position. Under the tutelage of Dr. Tharaka Doddapaneni a novel integrated process of biofuel production is being developed. In his research Dr Doddapaneni is studying the possibilities of integrating anaerobic digestion into the torrefaction-based biocoal production process. This will enable to give additional value to the production chain and lower the cost of the coal.

Recent publications:

Sjulander, Nikki; Kikas, Timo (2020). Origin, Impact and Control of Lignocellulosic Inhibitors in Bioethanol Production—A Review. Energies, 13 (18), 4751.10.3390/en13184751.

Hasanov, Isa; Raud, Merlin; Kikas, Timo (2020). The Role of Ionic Liquids in the Lignin Separation from Lignocellulosic Biomass. Energies, 13 (4864), 1−24.10.3390/en13184864.

Raud, Merlin; Kikas, Timo (2020). Perennial Grasses as a Substrate for Bioethanol Production. Environmental and Climate Technologies , 24 (2), 32−40.10.2478/rtuect-2020-0052.

Rocha-Meneses, Lisandra; Harris, Peter; Tait, Stephan; Antille, Diogenes L.; Kikas, Timo; McCabe, Bernadette K. (2020). Bioresource recovery in the Australian red meat processing industry: a technical review of strategies for increased circularity. 2020 ASABE Annual International Virtual Meeting, July 13-15, 2020. American Society of Agricultural and Biological Engineers (ASABE), 3−30.10.13031/aim.202000690.

Rocha-Meneses, Lisandra; A. Ferreira, Jorge; Mushtaq, Maryam; Karimi, Sajjad; Orupõld, Kaja; Kikas, Timo (2020). Genetic modification of cereal plants: A strategy to enhance bioethanol yields from agricultural waste. Industrial Crops and Products, 150 (C), 112408.10.1016/j.indcrop.2020.112408.

Cahyanti, Margareta Novian; Doddapaneni, Tharaka Rama Krishna C.; Kikas, Timo (2020). Biomass torrefaction: An overview on process parameters, economic and environmental aspects and recent advancements. Bioresource Technology, 122737.10.1016/j.biortech.2020.122737.

Rocha-Meneses, Lisandra; Otor, Oghenetejiri Frances; Bonturi, Nemailla; Orupõld, Kaja; Kikas, Timo (2020). Bioenergy Yields from Sequential Bioethanol and Biomethane Production: An Optimized Process Flow. Sustainability, 12 (1), 272.10.3390/su12010272.

Rauwel, Erwan; Al-Arag; Siham; Salehi, Hamideh; Amorim, Carlos O.; Cuisinier, Frédéric; Guha, Mihu; S. Rosario, Maria; Rauwel, Protima (2020). Assessing Cobalt Metal Nanoparticles uptake by Cancer Cells using Live Raman Spectroscopy. International Journal of Nanomedicine, 15, 7051−7062.10.2147/IJN.S258060.

Rauwel, Protima; Rauwel, Erwan (2019). Towards the extraction of radioactive Cesium-137 from water via graphene/CNT and nanostructured Prussian blue hybrid nanocomposites: A Review. Nanomaterials, 9 (6), 682.10.3390/nano9050682.

Rauwel, Protima; Ducroquet, Frédérique; Galeckas, Augustinas; Rauwel, Erwan (2019). Selective photocurrent generation in HfO2 and carbon nanotube hybrid nanocomposites under Ultra-Violet and visible photoexcitations. Materials Letters, 1.10.1016/j.matlet.2019.03.030.

Raud, M.; Kikas, T.; Sippula, O.; Shurpali, N. J. (2019). Potentials and challenges in lignocellulosic biofuel production technology. Renewable and Sustainable Energy Reviews, 111, 44−56. 10.1016/j.rser.2019.05.020.

Raud, M.; Krennhuber, K.; Jäger, A.; Kikas, T. (2019). Nitrogen explosive decompression pre-treatment: an alternative to steam explosion. Energy, 177, 175−182. 10.1016/

Rocha-Meneses, Lisandra; Raud, Merlin; Orupõld, Kaja; Kikas, Timo (2019). Potential of bioethanol production-waste for methane recovery. Energy, 173, 133−139. 10.1016/

Rocha-Meneses, Lisandra; Ferreira, Jorge A; Bonturi, Nemailla; Orupõld, Kaja; Kikas, Timo (2019). Enhancing Bioenergy Yields from Sequential Bioethanol and Biomethane Production by Means of Solid–Liquid Separation of the Substrates. Energies, 12 (19), 3683. 10.3390/en12193683.

Rocha-Meneses, Lisandra; Bergamo, Thaísa Fernandes; Kikas, Timo (2019). Potential of cereal-based agricultural residues available for bioenergy production. Data in Brief, 23, 103829. 10.1016/j.dib.2019.103829.

Rocha-Meneses, Lisandra; Silva, Jose Carlos; Cota, Sandra; Kikas, Timo (2019). Thermodynamic, Environmental and Economic Simulation of an Organic Rankine Cycle (ORC) for Waste Heat Recovery: Terceira Island Case Study. Environmental and Climate Technologies, 23 (2), 347−365. 10.2478/rtuect-2019-0073.

Rocha-Meneses, Lisandra; Ivanova, Anastasia; Atouguia, Guilherme; Ávila, Isaac; Raud, Merlin; Orupõld, Kaja; Kikas, Timo (2019). The effect of flue gas explosive decompression pretreatment on methane recovery from bioethanol production waste. Industrial Crops And Products, 127, 66−72.10.1016/j.indcrop.2018.10.057.

Raud, Merlin; Rooni, Vahur; Kikas, Timo (2018). The Efficiency of Nitrogen and Flue Gas as Operating Gases in Explosive Decompression Pretreatment. Energies, 11(2074). 10.3390/en11082074.

Pitman, Kätlin; Raud, Merlin; Scotti, Gianmario; Jokinen, Ville P.; Franssila, Sami; Nerut, Jaak; Lust, Enn; Kikas, Timo (2017). Electrochemical Characterization of the Microfabricated Electrochemical Sensor-Array system. Electroanalysis, 29, 249−258.10.1002/elan.201600559.

Podkuiko, L.; Olt, J.; Kikas, T. (2017). Growth of Scenedesmus obliquus under artificial flue gas with a high sulphur concentration neutralized with oil shale ash. Proceedings of the Estonian Academy of Sciences, 66(2), 151−158.10.3176/proc.2017.2.03.

Rocha-Meneses, Lisandra; Raud, Merlin; Orupõld, Kaja; Kikas, Timo (2017). Second-generation bioethanol production: A review of strategies for waste valorisation. Agronomy Research, 15(3), 830−847.

Rooni, Vahur; Raud, Merlin; Kikas, Timo (2017). Technical solutions used in different pretreatments of lignocellulosic biomass: a review. Agronomy Research, 15(3), 848−858.

Rooni, Vahur; Raud, Merlin; Kikas, Timo (2017). The Freezing Pre-Treatment of Lignocellulosic Material: A Cheap Alternative for Nordic Countries. Energy, 139, 1−7.10.1016/

Raud, Merlin; Mitt, Marion; Oja, Tõnu; Olt, Jüri; Orupõld, Kaja; Kikas, Timo (2017). Utilization potential of urban greening waste: Tartu case-study. Urban Forestry and Urban Greening, 21, 96−101.10.1016/j.ufug.2016.11.014.

Pitman, K.; Nerut, J.; Lust, E.; Franssila, S.; Raud, M.; Kikas, T. (2017). Electrooxidation of Hexacyanoferrate(II) Anions and Electroreduction of Oxygen in the Microfabricated Electrochemical Sensor-Array System. ECS Transactions, 77(11), 1771−1782.10.1149/07711.1771ecst .

Kikas, Timo; Tutt, Marti; Raud, Merlin; Alaru, Maarika; Lauk, Ruth; Olt, Jüri (2016). Basis of Energy Crop Selection for Biofuel Production: Cellulose vs. Lignin. International Journal of Green Energy, 13(1), 49−54.10.1080/15435075.2014.909359.

Tutt, Marti; Raud, Merlin; Kahr, Heike; Pointner, Manuel; Olt, Jüri; Kikas, Timo (2016). Nitrogen explosion pretreatment of lignocellulosic material for bioethanol production. Energy Sources, 38(12), 1785−1789.10.1080/15567036.2014.1002950.

Raud, Merlin; Olt, Jüri; Kikas, Timo (2016). N2 explosive decompression pretreatment of biomass for lignocellulosic ethanol production. Biomass & Bioenergy, 90, 1−6.10.1016/j.biombioe.2016.03.034.

Raud, Merlin; Tutt, Marti; Olt, Jüri; Kikas, Timo (2016). Dependence Of The Hydrolysis Efficiency On The Lignin Content In Lignocellulosic Material. International Journal of Hydrogen Energy, 41(37), 16338−16343.10.1016/j.ijhydene.2016.03.190.

Intellectual property:

1. Double walled cylindrical rotating photobioreactor with inner light source

Double walled cylindrical rotating biophotoreactor with inner light source, that includes closed vessel, which is formed by two horizontal double walled cylinders on the common rotational axes with a potential to rotate, outer and inner walls, endplates, and the fixed section that joins both rotating cylinders and is filled with microalgal solution. In the middle of the double walled cylinders inner light source is placed. The excess heat produced by the light source is dissipated using ventilator. Turning the light source on and off the switching mechanism is used. To the upper part of the fixed section the outtake of residual gases and input of nutrient solution with filters and valves are fixed. To the lower part of the fixed section the outtake of excess biomass and input of carbon dioxide (CO2) and/or air with filters and valves are fixed. The open ends of rotating cylinders are furnished with seals that make contact with the sliding surfaces of the fixed section. The closed ends are furnished with rolling-braces that prevent axial displacement.

Authors: Timo Kikas, Lara Podkuiko, Jüri Olt; Priority number: P201400048;

2. Nitrogen explosion pretreatment method for disruption of biomass structure