• Despite the fact that CSP technology has advanced, the cost of electricity from a CSP plant is five times higher than that of a photovoltaic power plant.
• In 2019, worldwide installed capacity is more than 6.5 GW
Solar Power Generation System
FIGURE Expected global cumulative capacity of CSP plant FIGURE Global cost of CSP electricity
Concentrated Solar Power (CSP) Market, Update 2019 – Global Market Size, Market Segmentation, Competitive Landscape and Key Country Analysis to 2030
Waste Sorting
and Disposal
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Waste Sorting System
Waste Sorting and Disposal❑ Waste Sorting : The process by which waste is separated into different elements to be recycled
• Manually at the household or Conveyor
• Automatically in materials recovery facilities(MRFs)
FIGURE Conveyor Infeed
https://www.youtube.com/watch?v=3q8sE2I6R7c https://commons.wikimedia.org/w/index.php?curid=8562192
FIGURE Waste Separation Process
<VIDEO>
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Waste Sorting System
Waste Sorting and Disposal❑ Manual Sorting : Sorting of waste materials by hand
• The most common waste sorting method at households
• Frequently at the beginning process in materials recovery facilities(MRFs), to sort out materials that can‘t by recycled
FIGURE Manual Sorting at households or Public places
https://commons.wikimedia.org/wiki/File:NEA_recycling_bins,_Orchard_Road.JPG https://commons.wikimedia.org/w/index.php?curid=8562192
FIGURE Manual Sorting in MRF
<VIDEO>
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Waste Sorting System
Waste Sorting and Disposal❑ MRF(Materials Recovery Facility) : A plant that separates and prepares single-stream recycling materials
• Waste materials are transported on Conveyor belts, go through various sorting processes
: Trommel screens, Air classifier, Magnetic separator, Optical separator, etc.
• Divided into two types : Clean MRF and Dirty MRF
FIGURE Materials Recovery Facility
https://www.rubicon.com/blog/materials-recovery-facility/
❑ Two Primary types of MRFs
• Clean MRF : Only processes residential or commercial single-stream recycling
→ The recovery rate is thought to be higher than at a dirty MRF
• Dirty MRF : Processes residential or commercial trash to recyclable materials that have incorrectly been thrown out as trash
→ Allows for greater overall recovery of recyclable materials, but costs more to run
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Waste Sorting System
Waste Sorting and Disposal❑ Trommel Screens : A mechanical device that rotates and performs size separation
• Solids from the entering flow will settle onto the screen mesh and the drum rotates
• Multiple Trommel screens can work together in series to separate waste by various sizes
https://www.wikiwand.com/en/Trommel_screen
FIGURE Trommel Screender
https://biannarecycling.com/en/trommel/
FIGURE Working Principle of Trommel Screender
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Waste Sorting System
Waste Sorting and Disposal❑ Air Classifier : A technological method of separating particulates according to their size
• Light & fine waste particles flow along with the air
• Many different types of air classifiers exist : counterflow, crossflow, vortex, inertial, etc.
Shapiro and Galperin, 2005
FIGURE Working Principle of Air Separator
https://www.youtube.com/watch?v=0TwJLS_Bars
FIGURE Different types of Air Classifiers
<VIDEO>
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Waste Sorting System
Waste Sorting and Disposal❑ Magnetism: A class of physical attributes that are mediated by magnetic fields
• Electric fields and magnetic moments of elementary particles give rise to magnetic fields
Lacovacci et al., 2016
FIGURE Types of magnetism
https://msestudent.com/which-metals-are-magnetic-list-of-ferromagnetic-and-ferrimagnetic-materials/
FIGURE Magnetism of Periodic Table at RT
❑ Types of Magnetism
• Paramagnetism
• Ferromagnetism
• Diamagnetism
❑ Waste materials can be sorted by their magnetic properties
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Waste Sorting System
Waste Sorting and Disposal❑ Magnetic Separator : Use powerful magnetic fields to separate ferromagnetic/paramagnetic materials from non-magnetic bulk materials
• Magnetic particles are being drifted by the movement of the drums, attatched to the belt due to magnets
• Magnetic particles then fall off from the belt for the separation
FIGURE Working Principle of Magnetic Separator
https://www.youtube.com/watch?v=3q8sE2I6R7c
<VIDEO>
https://www.youtube.com/watch?v=3q8sE2I6R7c
FIGURE Ferrous Material Separation
<VIDEO>
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Waste Sorting System
Waste Sorting and Disposal❑ Optical Separator : The automated process of sorting solid products using cameras and/or lasers
• Optical separators can recognize objects’ color, size, shape, structural properties and chemical composition
• Detects predetermined plastics such as bottles, film, etc.
FIGURE Working Principle of Optical Separator
https://www.youtube.com/watch?v=3q8sE2I6R7c
<VIDEO>
❑ Working Principle :
As waste passes the camera,
accurately timed and positioned air-jets propel selected items upward,
and off the conveyor belt
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Waste Disposal Methods
Waste Sorting and Disposal❑ Waste Management : The processes and actions required to manage waste from its inception to its final disposal
• Includes the collection, transport, treatment and disposal of waste, together of monitoring and regulation of waste
management process
FIGURE A Landfill
https://en.wikipedia.org/wiki/Waste_management#/media/File:Wysypisko.jpg
❑ Types of Disposal – Divided mainly into two : Landfill and Incineration
• Landfill : A site for the disposal of waste materials.
→ The oldest and most common form of waste disposal
• Incineration : A process in which solid organic wastes are subjected to
combustion
→ Convert waste materials into heat, gas, steam and ash
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Waste Disposal Methods
Waste Sorting and Disposal❑ Landfill : A site for the disposal of waste materials
• The oldest and most common form of waste disposal
FIGURE Landfill Gas Capture Facilityhttps://www.ccacoalition.org/en/activity/landfill-gas-capture-and-use
❑ Pros
• Easy and cheap : Easy to construct now landfills and cheap way to get rid of waste.
• Less greenhouse gas emission :
Compared to incineration, landfills less likely to produce greenhouse gases
• Energy generation : Gases from landfills can be used as fuels for energy
generation
❑ Cons
• Deforestation and pollution : Forests are damaged and groundwater/soil are polluted
• Sensory discomfort : Visually
unappealing / odors occur https://www.landfillodorproducts.com/landfill-odor-control/
FIGURE Landfill Odor
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Waste Disposal Methods
Waste Sorting and Disposal❑ Landfill Gas Utilization : A process of gathering, processing, and treating the methane gas emitted form decomposing waste
FIGURE Past and Present of ‘Nanjido’https://ncms.nculture.org/local-festival/story/488
https://www.seoulsolution.kr/ko/content/
FIGURE Side-view of 'Nanjido Park’
https://www.mk.co.kr/today-paper/view/2020/4645501/
• The Land Fill Gas(LFG)
: The gas that is generated when organic matter buried in landfills is
Decomposed by anaerobic microorganisms
→ Mostly Methane and Carbon dioxide
→ Can be used as a fuel
→ The third largest human generated source of methane (1st : fossil fuel 2nd : Agriculture)
Hao et al., 2008
TABLE Typical composition of LFG
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Waste Disposal Methods
Waste Sorting and Disposal❑ Landfill Gas Utilization : A process of gathering, processing, and treating the methane gas emitted form decomposing waste
FIGURE LFG Collection System FIGURE CO2 Separation
Membrane Skid FIGURE Landfill-gas-to-electric (LFGTE) Power plant
https://www.farmersrecc.com/content/landfill-gas-energy-plant
• LFG Collection:
- Installation of wells in waste mass
- LFG can also be extracted through horizontal trenches - LFG is Extracted and piped
to be treated or flared
• LFG Treatment:
- To remove impurities, particulates, etc.
- The treatment system depends on the end use (Boiler, Electricity generation, etc.) - Primary processing : Water and
particulates removal
- Secondary processing : Multiple Chemical/physical clean-up stages
• LFG Usage:
- Boiler, dryer, and process heater - Converted to CNG, LNG
- Electricity generation
→ Internal combustion engine
(RP engines mainly, due to low price) Or gas turbines
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Waste Disposal Methods
Waste Sorting and Disposal❑ Incineration : A process in which solid organic wastes are subjected to combustion
• Convert waste materials into heat, gas, steam and ash
FIGURE A Typical Waste Incineration Plant
Kaneko et al., 2019
❑ Pros
• Decreased quantity of waste: 80-95%
decrease in quantity
• Less pollution : Groundwater and soil pollution could be prevented
• Energy generation : Heat is generated in incineration process which can be used for electricity generation
• Effective metal recycling : Metals stay intact after burning, which can be recycled later
❑ Cons
• Expensive : It costs a lot to build infrastructure and maintenance cost is high
• Air pollution : CO2, SOx , NOx and particulates generated
https://you.38degrees.org.uk/petitions/stop-plans-for-waste-incineration-plant-in-chester-green-derby
FIGURE Waste Incineration Plant in Chester Green
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Waste Disposal Methods
Waste Sorting and Disposal❑ Waste Incineration Plant : The heat from the combustion generates superheated steam in boilers, and the steam drives turbogenerators to produce electricity
• Waste is crushed in Rotary crushers for easier incineration
• To prevent environmental problems, adequate flue gas filer is needed
• Ash can be used in constructions or land-fillings
→ Ferrous scrap metal contained in the ash can be recycled
FIGURE An Incineration Plant to produce electricity and heatMoya et al., 2017
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Waste Disposal Methods
Waste Sorting and Disposal❑ Food Waste Disposal : Food waste contain moisture and salt, which makes it hard to be buried or incinerated
• Utilized as Animal Feed / Compost / Biogas
FIGURE Animal feed made from food waste
http://m.ohmynews.com/NWS_Web/Mobile/img_pg.aspx?CNTN_CD=IE001
436645&tag=%uc74c%uc2dd%ubb3c%uc4f0%ub808%uae30&gb=tag https://m.segye.com/view/20171126002748
FIGURE Food waste turning
into Compost FIGURE Food waste Biogas Production Tank
• Animal Feed:
- Dry animal feed : Food waste dried in advance, then cooked in high temperature
- Wet animal feed : Food waste grated and sterilized, them mixed with existing feed (Pigs, Ducks, etc.)
• Compost:
- Aerobic composting : A method of decomposing food waste through the respiration of microorganisms by injecting air
- Anaerobic fermentation : A method of fermentation using bacteria that are active at a medium
temperature of 36 to 38 degrees.
• Biogas:
- Conversion of animal and plant-based organic waste into biogas such as methane
- During anaerobic fermentation, the gas can be used as fuel and the compost as fertilizer
Integrated Thermal
Management
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Separate TMS vs. Integrated TMS
• While the TMS in ICEV only radiates heat from the engine, EV TMS utilizes waste heat from electric motor in winter or cools down the overheated battery in summer
What is the integrated thermal management system?
Source: Caner Ezeroğlu: Thermal Management System for Combustion Engine Vehicles (canerezeroglu.blogspot.com) Source: hyundainews.com/en-us/releases/3059
Fig. Thermal management system of internal combustion engine vehicle (ICEV) and battery electric vehicle (EV)
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Driving Range Reduction Problem of EVs
• Electric vehicles (EV) consumes significant amount of energy in cabin heating and cooling
• Increased power consumption results in insufficient driving range, causing a fear called ‘Range anxiety’
Why is the integrated thermal management system important?
Fig. Effect of ambient temperature on EV mileage Fig. Available range of Nissan Leaf and Chevrolet Volt in different driving condition
Source [1]: Liu et al., Exploring the interactive effects of ambient temperature and vehicle auxiliary loads on electric vehicle energy, 2018 Source [2]: Fleetcarma, Nissan leaf vs Chevrolet volt cold weather range loss electric vehicle
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Thermal Management System in Human Body
• Human body should be maintained within proper temperature range (~37°C)
• Organs should cohesively operate to manage the thermal state of human body Why is the integrated thermal management system important?
Fig. Internal organs in human body[1] Fig. Thermal management system of body temperature[2]
Source [1]: kidsbiology.com/biology-basics/homeostasis/3 Source [2]: www.dreamstime.com
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Powertrain System in EVs
What does EV consist of?➢ EV powertrain components
DC link AC link
Lithium ion battery pack Inverter
Permanent magnet synchronous motor
Current, Voltage Current, Voltage
Driving-Charging Driving-Charging
➢ EV Powertrain heat generation
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Appropriate Temperature Range of Battery
How is the thermal state of battery managed?Source : Rugh, John P., Ahmad Pesaran, and Kandler Smith. "Electric vehicle battery thermal issues and thermal management techniques." SAE alternative refrigerant and system efficiency symposium. 2011..
➢ Optimal operating temperate of battery exists between two thermochemical effects
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Effect of Temperature on Battery Performance
How is the thermal state of battery managed?Source : Zhang, S. S. et al. “Charge and discharge characteristics of a commercial LiCoO2-based 18650 Li-ion battery." Journal of Power Sources 160.2 (2006): 1403-1409.
Fig. Impedance of battery under different temperature condition
Fig. OCV*-SOC* curve under various temperature condition
➢ Electrochemistry of battery is affected by temperature
OCV-SOC relation is relatively constant
under different temperature condition
Internal resistance of battery highly increases in low
temperature
*OCV: Open circuit voltage
*SOC: State of charge
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Analysis of Battery Thermal Management System
How is the thermal state of battery managed?FDM analysis
(MATLAB) CFD analysis
(Fluent) Experimental Study
Temperature field results using FDM analysis
BTMS*
*BTMS: Battery thermal management system
Source : https://www.youtube.com/watch?v=ucAGxakMVB4&ab_channel=ScheugenpflugGmbH
Temperature field results using CFD analysis Experimental results
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FDM Analysis with MATLAB
How is the thermal state of battery managed?Battery Stack heat generation and heat transfer model
𝜌𝐶𝑝𝑑𝑇
𝑑𝑡 = ሶ𝑞 + 𝑘𝑥𝜕2𝑇
𝜕𝑥2 + 𝑘𝑦 𝜕2𝑇
𝜕𝑦2 + 𝑘𝑧 𝜕2𝑇
𝜕𝑧2
𝜌𝑐𝑝𝐴∆𝑥𝑑𝑇
𝑑𝑡 = ሶ𝑄𝑠𝑡𝑎𝑐𝑘2𝑐𝑜𝑜𝑙 + ሶ𝑚𝑐𝑝(𝑇𝑖−1 − 𝑇𝑖)
◆ Governing equations
Battery Stack:
Cooling path:
◆ Heat generation calcuation 𝑄 = 𝐼 𝐸 − 𝑉 + 𝐼𝑇𝜕𝐸
𝜕𝑇 = 𝐼2𝑟 + 𝑇∆𝑠 𝐼 𝑛𝐹 𝑄𝑖 = 𝐼2𝑟
𝑄𝑟 = 𝑇∆𝑠 𝐼 𝑛𝐹
(Heat generation from internal resistance)
(Heat generation from reversible entropy change)
Nucool = Nucool,0 + 0.499 𝐷ℎΤ𝐿 ∙ Recool ∙ Prcool (for laminar flow)
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Different Motor Cooling Methods
How is the thermal state of motor managed?➢ Motor cooling methods have different cooling performance and cost
Fig. Cooling performance of each motor cooling method and its application
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Heat Generation of PMSM
How is the thermal state of motor managed?Fig. Heat Losses in motor
Fig. Hysteresis loss
Heat generation model for permanent magnet synchronous motor (PMSM)
(rotor and stator)
[W/m3]
kh= Hysteresis constant ke= Eddy current constant 𝜷 = Steinmetz constant 𝝎 = Angular velocity [rad/s]
𝑩 = Magnetic flux density [ T ] or [Wb/m2]
Ieff= effective or RMS (root mean square) current
= 𝑰𝑨𝑪.𝒎𝒂𝒙
𝟐 , [A]
Rcu= resistance [Ω]
(Stator and coil)
▪ Heat generation in PMSM mainly consists of iron loss, copper loss, and mechanical loss
▪ Heat generation of PMSM determines the temperature of motor with thermal resistance model
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Thermal Resistance of PMSM
How is the thermal state of motor managed?Thermal resistance model in PMSM (MATLAB based)
▪ Heat transfer between each PMSM parts are estimated through thermal resistance model
▪ Local temperature of PMSM can be calculated through thermal resistance model and heat generation model, presenting the cooling performance thermal management system
Fig. Schematic of PMSM and thermal resistance circuit Fig. Thermal resistance in the PMSM
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Oil Cooling Method
How is the thermal state of motor managed?Source : Bennion, Kevin. Electric motor thermal management. No. NREL/PR-5400-76670. National Renewable Energy Lab.(NREL), Golden, CO (United States), 2020.
➢ Oil cooling method is suggested and tested
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Refrigerant Cooling Method
How is the thermal state of motor managed?➢ Refrigerant cooling method shows better cooling performance
Fig. Refrigerant cooling system
Fig. Performance of refrigerant cooling
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Importance of Integrated Thermal Management
Integrated thermal management is important!Source: https://www.afdc.energy.gov/vehicles/how-do-all-electric-cars-work
▪ EV consists of many electric components having different thermal requirements
▪ Thermal state determines not only the performance of EV but also safety and life of the EV
▪ Therefore, proper thermal management system is just as important to EVs as maintaining body temperature is important to humans.
Fig. Configuration of human body and EV
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