Thermal storage for process steam generation: The TESIN project Maike Johnson IEA Working Party on Energy End-Use Technologies Garching – March 1, 2016
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 1
DLR German Aerospace Center
• Research Institution • Space Agency • Project Management Agency
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 2
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 3
Locations and employees
8000 employees across 33 research institutes and facilities at 16 sites.
Offices in Brussels, Paris, Tokyo and Washington.
Köln
Oberpfaffenhofen
Braunschweig
Göttingen
Berlin
Bonn
Neustrelitz
Weilheim
Bremen Trauen
Lampoldshausen
Hamburg
Stuttgart
Stade
Augsburg
Jülich
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 4
Energy Research Program Themes
• Efficient and environmentally compatible fossil-fuel power stations (turbo machines, combustion chambers, heat exchangers)
• Solar thermal power plant technology, solar conversion
• Energy storage (thermal, chemical, electrical)
• High and low temperature fuel cells • Systems analysis and technology
assessment
Institute of Engineering Thermodynamics Prof. André Thess
Thermal Process Technology Dr. A. Wörner
Electrochemical Energy Technology
Prof. A. Friedrich
System Analysis and Technology Assessm. Dr. Schillings/C.Hoyer-Klick
„... scientific pathfinder for the storage industry...“
Computational Electrochemistry
PD Dr. A. Latz
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 5
Core Technologies for Thermal Process Technology
• High temperature heat exchangers • Sensible thermal energy storage
• Concrete • Regenerator type • Molten Salt
• Latent heat energy storage with salts • Thermochemical systems (utilization of reversible gas-solid-reactions) • Techno-economic evaluation of processes for the generation of fuels
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 6
Competences in Thermal Process Technology
• Characterization and synthesis of storage materials
• Detailed modelling of physical and chemical phenomena
• Design and fabrication of innovative storage concepts and components
• Operation and experimental investigation of prototypes in relevant scale (140-1000 °C, 1-1000 kW)
• System analysis and integration of thermal energy storage
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 7
Thermal Energy Storage as a Cross-Sectoral Technology
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 8
Key Performance Indicators o Storage density (system)
o System cost (CAPEX, OPEX)
o Space needed
o CO2-mitigation potential
o Operating characteristics …
Storage Technology
Thermo-chemical
Latent Heat
Sensible Heat
Application Storage Requirements
o Temperature level o Heat transfer fluid o (Dis-) Charging characteristics o Storage capacity o Power density
Storage Concepts
liquid solid/liquid
Salts, solid-liquid Salts, solid-solid
Gas-solid reaction Sorption
solid Sensible
Heat
Latent Heat
Thermo-chemical
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 9
Storage Concepts
20 – 100 kWh/m³ (depending on temperature difference)
Energy density [kWh/m3]
low Sensible
Heat
Latent Heat
Thermo-chemical
50 – 150 kWh/m³ (for minimal temperature difference)
100 – 400 kWh/m³ (depending on driving temperature or pressure gradient)
Development status high
high low
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 10
• Energy efficiency potential in electric steel processes of BSE/BSW • analysis of thermal energy storage integration • economic potential
• Applicability of thermal storage in • heating stations and • combined heat and power stations with the project partner SNE
• Development and test of a latent heat storage for cogeneration plant • high temperature • high heat rate • produce superheated steam
• Software tool for the assessment of industrial processes • thermal storage integration • energy efficiency
TESIN: Thermal Energy Storage for Increasing Energy Efficiency in Cogeneration Power Plants and Electric Arc Steel Plants
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 11
TESIN: Application in cogeneration power plant
Challenge • Process steam for foil production plant • Constant steam conditions mandatory ⇒ Currently: continuous operation of gas burners for emergency case ⇒ Introduction of latent heat storage to cover start-up time of gas burners ⇒ Reduction of primary energy needs
Requirements for latent heat storage • Temperature 300 ºC • Heat rate 6 MWth • Storage capacity 1,5 MWth ⇒ Extremely high power density
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 12
TESIN: Integration in the cogeneration plant
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 13
G
HRSG
Gas turbine
Waterinjection
Steam mainto customer
Feedwatertank
Stack
PCMstorage
Stack
Back-upboiler
Latent heat storage Phase change material (PCM) aspects
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 14
0
50
100
150
200
250
300
350
400
100 150 200 250 300 350Temperature [°C]
Enth
alpy
[J/g
]
KNO3
NaNO3NaNO2
KNO3-NaNO3
LiNO3-NaNO3
KNO3-LiNO3
KNO3-NaNO2-NaNO3
LiNO3
0
50
100
150
200
250
300
350
400
100 150 200 250 300 350Temperature [°C]
Enth
alpy
[J/g
]
KNO3
NaNO3NaNO2
KNO3-NaNO3
LiNO3-NaNO3
KNO3-LiNO3
KNO3-NaNO2-NaNO3
LiNO3
• Nitrate salts are possible PCMs for applications above 100 °C • Important PCM criteria are melting enthalpy and melting temperature, as
well as thermal stability, material costs, corrosion and hygroscopy
solidified NaNO3
liquid NaNO3
Phase Change Storage Current Status
• Finned tube storage concept demonstrated: • graphite fins / horizontal tubes => T T Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 15
solid
liquid
Fluid
solid
liquid
Fluid
• Heat transfer is dominated by the thermal conductivity of the solid PCM
• Low thermal conductivity is bottleneck for PCM Heat carrier: water/steam
Phase Change Material (PCM)
Tube
Fins
Simplified PCM-storage concept
Finned Tube Design effective k > 10 W/ (mK)
Latent heat storage concepts
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 16
solid
liquid
Fluid
solid
liquid
Fluid
Further development of the extended fin concept
• Axial fins provide a channel for liquid salt convection and expansion
• Simplified assembly through automation
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 17
TESIN: Storage design
• First large-scale high temperature PCM storage to use extruded aluminum fins
• Storage medium: NaNO3 • Melting temperature: 306 °C • Design mass: ~30 t
• Heat transfer fluid: Steam/Water
• Power level: 6 MW • Capacity: >1.5 MWh
• Dimensions: 2 m x 1.5 m x 8 m • Approx. 850 finned tubes
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 18
• Large scale high temperature latent heat storage being integrated into a running co-generation plant by summer of 2016
• First large scale application of extruded aluminum fins in realization
• High power levels (6 MWth) and production of superheated steam
• Replacement of standby-operation of back-up boiler, thereby reduction of fossil fuel use
• Valuable data will be collected during operation in 2016 and 2017
Conclusions & Outlook
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 19
Discussion
Maike Johnson [email protected] + 49 711 6862 344
The TESIN project, within which this research is being conducted, is partly funded by the German Ministry of Economic Affairs and Energy under the contract number 03ESP011A-C. This is a cooperative project together with STEAG New Energies GmbH, Badische Stahl-Engineering GmbH, F.W. Brökelmann Aluminium GmbH & Co. KG and Badische Stahlwerke GmbH.
Back-up: Material Properties
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 21
Property [Unit] ↓ / Material →
Steel tube
Aluminum fin
NaNO3 PCM, ave.
Effective material
Density [kg/m3] 7850 2700 2010.5 2114.5
Spec. heat capacity [J/(kg K)]
554 1020 1655 1532.8
Heat conductivity [W/(m K)]
45 210 0.55 0.12…169
Latent heat [kJ/kg]
- - 178 143.73
Simulated temperatures in the storage and heat transfer medium during discharging
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 22
Feedwater inlet
Steam outlet
Temperature distribution T and liquid phase fraction f in the 70mm diameter fin geometry during charging
17.6 %
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 23
75.9 % 98.9 % State of Charge:
• Analysis: over 200 plant profiles, categorized in 6 groups by heat source, client structure and payment model.
• Potential for high temperature storage in the ‘Biomass’ and ‘Industry’ groups.
TESIN: Market Potential for Storage Integration in Cogeneration Plants and Back-up Processes
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 24
• Potential: efficiency increase through load compensation, MRL and SRL, minimizing start-up time
• Integration possibilities have been demonstrated
• limitations due to constraints in turbine operation (pressure reduction)
• Profitability of retrofit is critical
• Integration in new plants with optimized process configuration
Energy End-Use in Germany in 2010
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 25
Overall Industry
Source: AGEB 2012
Lighting
Hot water
Information and Communication Tech.
Mechanical Energy
Refrigeration and Air Conditioning
Process Heat
Space heating
• Almost 57 % of all energy is used for supply of heat. • 70 % of the energy in industry is used for process heat.
• Reduce energy and resources consumption within the existing installed base of industrial processes by more efficient use.
• Re-use waste streams and energy within and between different sectors, including recovery, recycling and re-use of post-consumer waste
• Replace current feedstock by integrating novel and renewable feedstock. Replace current inefficient processes.
• Reinvent materials, products and processes to have a significant impact on resource and energy efficiency over the value chain.
Future Vision for the Process Industry
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 26
Source: SPIRE Roadmap 2013
• Reduce – increase energy efficiency by integration of thermal energy storage i.e. for batch processes
• Re-use – utilize process waste heat for re-integration into the process, generation of power or cold
• Replace – Power-to-heat on higher temperature levels
• Reinvent – Thermal energy storage materials, process design with thermal energy storage
Possible Thermal Energy Storage Contribution
> Thermal storage for process steam generation ̶ The TESIN project > Johnson • EUWP Workshop > 01.03.2016 DLR.de • Slide 27
Source: SPIRE Roadmap 2013
Thermal storage for process steam generation:�The TESIN projectDLR�German Aerospace CenterSlide Number 3Slide Number 4Slide Number 5Core Technologies for Thermal Process TechnologyCompetences in Thermal Process TechnologyThermal Energy Storage as a Cross-Sectoral TechnologyStorage Concepts�Storage Concepts�TESIN: Thermal Energy Storage for Increasing Energy Efficiency in Cogeneration Power Plants and Electric Arc Steel PlantsTESIN: Application in cogeneration power plantTESIN: Integration in the cogeneration plantLatent heat storage�Phase change material (PCM) aspectsPhase Change Storage�Current StatusLatent heat storage conceptsFurther development of the extended fin conceptTESIN: Storage designConclusions & Outlook DiscussionBack-up: Material PropertiesSimulated temperatures in the storage and heat transfer medium during dischargingTemperature distribution T and liquid phase fraction f�in the 70mm diameter fin geometry during chargingTESIN: Market Potential for Storage Integration in Cogeneration Plants and Back-up Processes�Energy End-Use in Germany in 2010Future Vision for the Process IndustryPossible Thermal Energy Storage �Contribution
