Energy efficient use of low temperature excess heat in industry

Tiina Järvinen Aalto UniversitySchool of EngineeringDepartment of Energy Technology

11.3.2013

Tiina Järvinen

Doctoral Program in Energy Efficiency and Systems / EES Starting seminar

Contents

• Motivation

• Aim of the research

• Publications

• On-going work for doctoral thesis:Potential of excess heat in Finnish industryEnergy storage: Biomass drying

• Continuity for dissertation:Heat recovery in moist air heat exchanger

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Motivation

• The European Union targets by 2020: o To reach 20% savings in primary energy useo To increase use of the renewable resources by 20%o To decrease 20% CO2 emissions

• The energy efficiency is consistently identified as an essential means of moving to a more sustainable energy future. Energy efficiency curbs energy demand growth, reduces energy imports and mitigates pollution. (World Energy Outlook, 2012. International Energy Agency.)

• EFEU research program (CLEEN)

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The Aim of the Research

Tiina Järvinen

Þ The industry is the most significant end user of energy/electricity.Þ Energy efficient use of low temperature waste/excess heat in industry.

Finding means to use excess heat of the industry effectively.

• decreasing the primary energy need and the CO2 emissions.

• conversion and up-grading technologies (e.g. Conventional methods –heat exchangers, Kalina cycle, ORC, heat pumps, drying…)

Publications

• 2012: State of the art report:– Järvinen, T. Technology characterization – Conversion and Up-grading Technologies for

Low Temperature Heat Source

• 2013-2014: Publications– Järvinen, T. & Holmberg, H. Theoretical Potential to Convert Excess Heat into Mechanical

Work in the Finnish Industry . Conference paper (PRES’13, 16th Conference Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction), abstract accepted, to be submitted.

– Järvinen, T. & Holmberg, H. & Hillamo, H. Energy storage: Biomass drying with low temperature heat

– Järvinen, T. et al. Heat recovery in moist air heat exchanger (modified processes to reduce primary energy consumption)

Tiina Järvinen

On-going work for doctoral thesis:Potential of excess heat in Finnish industry

• Evaluation of theoretic potential to convert excess heat into electricity in the industry (refining of metals, forest and chemical industry)

• Classic exergy analysis

• Speculation of realistic potential in industry to use excess heat

• Results indicate the total theoretical potential to be 6.9 TWh/y.

• To be submitted.

• Conference paper (PRES’13, 16th Conference Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction)

• Main reference of the paper: Utilization of excess heat of the industry in district heating. (In Finnish) [Teollisuuden ylijäämälämmön hyödyntäminen kaukolämmityksessä, YIT Teollisuus- ja verkkopalvelut Oy, Projekti numero 860308.] 2010.

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On-going work for doctoral thesis:Energy storage: Biomass drying

• Drying as heat recovery unit -> increases LHV of biomass.

• Heat source at low temperature (excess heat, solar energy)

• Experimental research (drying equipment in Aalto, Drying of woodchips) -> drying curves from the experimental data

• Focus of the article on the drying process

Tiina Järvinen

Energy storage: Biomass drying

Tiina Järvinen

Continuity for dissertation:Heat recovery in moist air heat exchanger

• A case study / article

• In collaboration with Kumera Oy

• Harjavalta: pilot (indirect steam dryer and preheater)

• Theoretical model versus experimental data

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Heat recovery in moist air heat exchanger

Tiina Järvinen

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THANK YOU FOR YOUR ATTENTION!

Tiina Järvinen