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By:
Group B4
8/16/2012
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Indias electricity requirement
How to meet? New Power Plants
Alternate sources of energy
Improvement of existing power plants - the most cost effective option
The importance of R&M was recognized by the Government of India way
back in 1984 when PHASE-I R&M Programme for 34 thermal powerstations in the country was launched by the Central Electricity Authority as
a Centrally Sponsored Scheme
The life extension (LE) programme focuses on plant operation beyond their
original design life after carrying out specific life assessment studies ofcritical components
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The equipment subjected to fatigue stresses and creep due to high
temperatures such as turbine rotor and casings, HP piping etc. are
designed for a given fatigue life of about 25-30 years of operation
Many equipment/components might become prematurely weak due tovarious operational stresses like frequent temperature and pressure
excursions, full load trippings, frequent start and stops etc. and
accordingly there is need to check the remaining life of these
components after about 20 years of life or 1,60,000 hours of operation
A detailed condition assessment along with performance evaluation ofvarious systems / sub-systems is carried out to identify the
modifications / replacements required to enable plant operation for a
longer period
It is a good practice to examine whether a plant requires a viablemodernization intervention so that during the extended life the plant
operates efficiently and delivers the rated or higher capacity with
improved heat rate
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Design deficiencies, manufacturing and generic defects
The Operation and Maintenance (O&M) deficiencies causing prolonged andrepetitive forced outages
Inadequate and non timely availability of spare parts especially for
imported equipment
The quality of coal being supplied has deteriorated as compared to the
deigned quality. Besides, the coal has high ash content and contained
stones, boulders, shale and sand
There is excessive and inadequately trained manpower for the O&M of the
plant.
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Extension of life of generation unit by 10-15 years Improvement of availability of the generation unit
Sustained achievement of near-design (or better) maximum continuousrating (MCR)
Improvement in energy efficiency of boiler, turbine, generator and
auxiliaries, resulting in improvement of unit heat rate Achievement of lower secondary oil consumption through reduction in
number of tripping, faster start-up and stable combustion at even lowerlevels of load.
Overcome the problem of aging of critical components (leading to lower
reliability and shorter residual life) and non-availability of critical spares(due to obsolescence).
Incorporation of advanced control and instrumentation systems.
Reduction in emissions and improved environmental control.
Facilitate adoption of improved operations and maintenance practices.
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A large capacity of about 5,000 MW was installed in 1970s PLF of these units was as low as 40%
Stabilisation teams comprising engineers from CEA, BHEL, ILK and the
concerned power utilities were formed.
Stabilisation Teams identified the problem areas
teething problems and failures due to inherent design defects
modifications were carried out free of cost by the manufacturers on all
the existing units
the performance of these units substantially improved and got stabilised 160 units of 200/210 MW comprising about 44% of the total thermal
installed capacity in the country
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Engineers from CEA, SEBs/Power Utilities, BHEL, ILK and Keltron
visited various thermal power stations in the year 1984-85 and
assisted SEBs in identifying areas of attention and formulation of
R&M Schemes
CEA formulated a proposal called PHASE-I R&M Programme as aCentrally Sponsored Scheme for R&M of thermal power stations in
the country
Central Loan Assistance (CLA) of Rs.500 crores to provide financial
assistance to the SEBs
47% of the total investment was made on environmental pollution
control measures
Till the formation of Power Finance Corporation (PFC) in April
1988, funds were managed by CEA
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PHASE-II R&M programme for 44 thermal power stations in the country was
taken up in the year 1990-91 for completion during the 8th Plan period
Roving Teams constituted for PHASE-II of the programme visited various thermalpower stations and assisted SEBs in the formulation of R&M schemes
Power Finance Corporation (PFC) was assigned the responsibility to provide loan
assistance to the SEBs for R&M works.
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9th Plan R&M Programme was taken up in 127 units at 29 thermal powerstations
25 nos. of thermal units which had already completed their designed life
were planned for LE works based on Residual Life Assessment (RLA)
studies during the 9th Plan
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The CEA has identified 106 thermal units in consultation with SEBs/State
Generation Corporations for LE during the 10th Plan so as to extend their
economical life by another 15-20 years and to recapture /up-rate their capacities by
implementing comprehensive R&M schemes based on RLA studies.
Another 57 units of 14270 MW capacity which are comparatively new also needsome R&M work to sustain/improve their performance.
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During the 11th Plan, 53 units with a total capacity7,318 MW are programmed to be taken up for LE.Another 76 units with a capacity of 18,965 MW wouldbe taken up for R&M
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Life extension works have been identified on 72 thermal units of total
capacity 16532 MW
30 units (5860 MW) from state sector and 42 units (10672 MW) from central
sector
R&M works have been identified on 23 units (4971 MW) during the 12th
Plan, out of this 11units (4050 MW) are from NTPC, 9 units (291 MW) are
from NEEPCO and rest are from state sector
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R&M of TG Replacement of most of the Buckets, Nozzle Plates, Diaphragms, all TG
Bearings, Labyrinth Seals, ESV Parts, Control Valve parts, Governor parts Turning Gear parts Steam seal, Condenser Tubes R&M of C&I
Spare Gen. Rotor R&M of Electrical
Replacement of Static Excitation System , Power & Control cables. Replacement/ Retrofit of HT/LT Switchgear Augmentation of H2 plant
R&M of BOP Renovation of Cooling Towers Augmentation of Ash Handling New AWRS New Railway Siding inside the plant New Coal Handling Plant R&M of Switchyard
SomeExamples
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The methodology adopted for life assessment can be categorized into:
Operational data, standard material based on properties. Methods based on past service examinations or past service tests on
the actual components.
The RLA program may be carried out as follows:
Site study, collection of data and assessment of actual conditions.
Finalization of action plan for carrying out detailed study and tests.
Various NDE and Destructive tests on components and equipmentsof the boiler to meet the scope.
Analysis of results & report.
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For the operating part : The operating parameters like pressure & temperature Incidents, events of failure & repair statistics Condition of plant facility by number of starts/stops & service
hours
For the maintenance part :
Review of component replacement & repair Review of component geometry
For the inspection part : Non destructive testing results where the most important are :
Wall & internal oxide thickness measurement by ultrasonics Metallographic examination by replication Stress measurements by strain gages
Destructive material testing like failure analysis, isostress creeptesting
Boiler
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NDE & DE Tests: Scope of condition assessment of Boiler
VT Visual Testing
FOB Fiber Optic Boroscope
DIM Dimension Measurement
MT Magnetic particle testingPT Dye penetrant
UTG Ultrasonic thickness testing
UFD Ultrasonic Flaw Detection
IRIS/ UT Internal Rotary InspectionSystem / Submerged UT
HB Insitu Hardness MeasurementIMG Insitu Metallography
ICA Insitu Chemical Analysis (PMI)
OSM Oxide Scale Measurement
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Following information are required to be collected regardingthe set whose life is to be estimated:
The drawings of critical components viz. rotors, casings,valves & valve chests, guide blade carriers, steam inlet &
exhaust connections etc. Materials of various critical components as mentioned
above & their test certificates including NDT results likedefectograms etc.
Thermodynamic cycle and strength design data. Stressdistribution in various critical components as envisagedduring design stage.
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The effectiveness of the calculations made for RLA depends
upon the accuracy of this data.
The observations during planned shut downs provide lot of
information on equipment's condition
Maintenance Planning Division of the power plant utilizes this
information for preventive maintenance and replacements
History cards covering the replacements done during routine
maintenance / forced outages and planned overhauls are
reviewed so that present status of the equipment is assessed andequipment degradation trend is formulated.
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After thorough cleaning of the rotor surface and blading, followingexaminations are carried out :
Visual examination of the rotor surface, moving blades andshrouds for any abnormality.
Boroscopic examination of rotor bore
Magnetic particle examination and/or dye penetration test of therotor with special emphasis on the inlet zone, blades and shrouds.
Ultrasonic test of accessible areas of the rotor for internal defectsto ascertain major flaws and how far they have grown frominitial stage of manufacture.
Special attention is given to inlet zone of the rotor. Hardness and Microstructure testings at steam entry and exit
sides
Natural Frequency Measurement of free standing blades of LPmotor.
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All stationary components viz. turbine casings & guideblades, high temperature inlet & exhaust connections, stop& control valves, strainer housings, U, I, & L- seal rings,gland seal bodies etc. are cleaned thoroughly and followingexaminations are carried out :
Visual examination of the component with specialemphasis to the transition zones and welded areas forcrack, corrosion, erosion or any other defect
Magnetic particle inspection and/or dye penetration test to
detect surface and sub-surface cracks Ultrasonic examination for internal defects
In-situ microstructure examination and hardness test
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High temperature fasteners
All the fasteners of high temperature zone will be checked fordetection of cracks by MPI / DPT / UT.
Sample survey of turbine inner casing joint plane fasteners ofhigh temperature zone is carried out by destructive test onsample studs to determine mechanical properties and impactvalues
Microstructure examination is also carried out
Bearings
All turbine bearings are checked visually for any damage, byDP test for cracks, and by UT for babbit bondage.
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Remaining life of steam turbine components. Immediate replacement of a component is required or
it can be replaced after a prescribed period.
Repair of a particular component
Change in steam parameters at the inlet, if required. De-rating of steam turbine.
Alterations in the mode of future operation of the set.
Alterations in the material of certain components Need for more often inspections.
Proposals for R & M.
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Use of improved blade profile which result into reduction inthe aerodynamic flow losses e.g. profile loss, secondary flowloss & tip leakage loss.
More uniform flow distribution.
Optimization of flowpath.
Improvement in shaft sealing system.
Reduction in pressure drops.
Reduced friction losses.
Optimization of inlet & exhaust section geometry of valves &casings.
Optimization of exhaust loss.
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The boiler itself may be changed to membrane water wall type. Modified furnace bottom sealing system may be retrofitted to
avoid air ingress.
New bottom ash handling system may be retrofitted
Modified up graded materials have been envisaged to meetbetter reliability in performance and reduction in boiler tubeleakages.
Better soot blowing system to obtain a clean boiler surface.
New design coils with fins to minimize flow flue gas velocity
to reduce erosion failure. Replacement of existing design of economiser coil to provide
for better expansion to meet high ash content of presently usedIndian coal .
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Since mills were designed for a better coal and the same
coal was not available, major modifications may be
carried out in milling system and combustion control
equipments to meet the fuel demand and combustion
requirements.
New low Nox burner to meet environmental norms.
Ceramic lines/ pulverized lines to get better life and
reduce the leakages. New burners to get better life and utilizing latest
technologies.
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Since the combustion and quantity of fuel burned haschanged due to deterioration in coal quality, modification
of flue gas ducts, supports, ash handling system may
require to be retrofitted and the sizing of the fans may also
be reworked and modified. Induced draft fans with either hydraulic coupling or with
VVF drives are envisaged.
Better secondary air control.
Retrofitting dry ash evacuation system to achieve 100%
ash utilization may also be considered.
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Air preheater
Retrofitting of latest technology with more advanced design In place of tubular, modular design is now preferred.
Better flow modelling to achieve uniform velocity.
Separation of primary air and secondary air to gain the betterheat requirements.
Rotary air heater with modified sector plates
Better static seals
Double lip rotary seal
More expansion and better sealing to cater for load variation
Better flow modelling to avoid flow channelling Better expansion joints to avoid excessive ID fan loading
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To meet the latest environmental norms for Suspended
Particulate Matter (SPM):
New modified ESP to be retrofitted
New fields to be added Advance corona based microprocessor based control
system to be introduced
Advanced rectifiers to collect more ash
Increase the retention time to achieve better efficiency
Retrofitting new advanced spike electrodes, rotating
electrodes to achieve the environmental norms
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Introducing advanced blade design to reduce the surface andexit losses, modified shaft sealing, reduction in bearing lossesand optimization of admission and exhaust sections,improvement in regenerative feed water heaters and controlvalves.
New turbine internals with modified blades or the retrofittingof LP turbine may be considered.
There can be an increase of about 1.8 to-3.8 MW increase byretrofitting the LP turbine by utilizing the thermodynamicenergy of buoyancy steam.
In order to attain the best result in the LP turbine, latest designtapered and forward leaning guide can be used which help toavoid the flow separation in the root area and lead to betteroutput.
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By redesigning the exhaust, the exit pressure losses can bereduced and better output has been achieved.
Technologically the cylindrical design blades i.e. with aconstant profile over the entire length of blades areretrofitted with newly developed 3D blades using CFDmodelling.
This development of blade profiles has led to reduction insecondary losses and increase in power output andefficiency- these blades are known as Tx blades.
The frequency control regime would require frequent loadvariation capability. The control system (electro-hydrauliccontrol system) has been modified.
Modification or re-tubing of condenser and introducingonline tube cleaning mechanism are recommended.
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Generator Normally, rewinding is considered with class F
insulation to meet new temperature limits
Control system
New control valves and actuators retrofitting Incorporation of new DCS system
Retrofitting the On-line optimization system
Modification of BOP
Necessary modifications to ensure systemcompatibility
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Efficacy of RLA studies . Selection of optimal design options for repair, restoration and
replacement.
Packaging concept-Turnkey or Multiple packaging
Guarantees, penalties, scope growth, cost overrun and delays to watchinterest of all concerned.
Long delivery schedule for major components of turbine especiallyforgings & castings.
Addressing of Balance of plant generic issues and proper assessment.
Shortage of energy (difficulty in getting shutdowns). Long term debt for R&M to keep cost of generation low.
Establishing techno-economic viability.
Complexity in complying environmental concerns.
Regulatory mechanism needs to be conducive for R&M
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There have been steep breakthroughs in Power planttechnology which have brought considerable enhancement inefficiencies & reliability.
Therefore, for old plant vintages it may be worthwhile toconsider mega R&M schemes to bring these plants up to the
contemporary state of the art plants in terms of efficiency,reliability, etc.
Typically, such mega R&M may include up rating, re-powering, higher process parameters resulting in enhancedefficiency, improved operational safety, reliability, advanced
diagnostics, etc. Mega R&M typically consists of replacements of major
equipment / systems of the plant at marginally higher cost &longer shutdowns of the Units are inherent.
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Renovation of Every plant is a unique challenge and is plant specific/utility specific and solutions are to be customized to suit specific needs.
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ESCO is an organization engaged in a performance based contract with a clientfirm to implement measures which reduce energy consumption and costs in a
technically viable manner
Advantages of ESCO Business Model:
Reduction of Fossil Fuel consumption
Potential for generating Carbon Credits which can lead to increased revenue
Increases Process Industries profitability & also its share value
Enables the Process Industries to retain long term Employees & attract qualitynew recruits
Enables sharing of financial risks
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In 2006, an ESCO association, the Indian Council for Promotion of EnergyEfficiency Business (ICPEEB) was founded.
Until now, ESCO promotion measures have been implemented throughsupport from international agencies, mainly USAID
In India there was technical training via USAID
The overall energy efficiency investment market size under ESCO system ofperformance contract in India has been estimated by the ADB Study project
team at Rs. 14000 crores and has the potential to save about 54 billion units ofelectricity annually
On the financial front, low interest financing has been implemented, but manymeasures that should be considered, such as subsidies, tax incentives, and aloan guarantee system, are left .
Further, along with private sector activities, government organizations alsoneed skill development. Strengthening of policies is also needed.
Low interest financing programs have been in India by the World Bank, ADB,JBIC, and USAID
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Bleeding EdgeTechnology
EMC Contract BOOT/ BOT if
required
Long term finance Innovative Lending
All ESCO services Land and otherinfrastructure
Capital, if required Long term
commitment
Customer ESCO
Equipment/
TechnologyPartner
Financial
Institutions
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In order to create a sense of credibility amongst the prospective agencies that are likelyto secure the services of an ESCO as well as the financial institutions, a process ofrating ESCOs was taken up through CRISIL (Credit Rating and Information Services of
India Ltd.) and ICRA (Investment Information and Credit Rating Agency of IndiaLtd.)
CRISIL and ICRA present the criteria for grading and a summary of the gradingassigned to the ESCOs and their comparable scores on the parameters for assessment
A set of criteria was devised to evaluate : Business Risk Factors- essentially track record and market position in ESCO/energy
management businesses Organizational Risks- ability of the management to gear up for ESCO contracts Financial Risks- financial strength of the company to invest in ESCO projects
A 100 point scale has been devised based on the above parameters with a 20% weight-age given toBusiness Risks, 40% weight-age to Organizational Risks and 40% to Financial Risks
The parameters for assessment include:
Years in the ESCO/energy management business.
Number and nature of energy audits carried out till date.
Client Profile
Number of different industries served.
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Order book strength as measured by ratio of current order book/previous years turnover.
Number of energy management projects completed.
Certification and quality systems. Technology tie-ups.
Patents held by the company.
R&D facilities.
Constitution, ownership structure and parentage.
Management evaluation and quality of organizational structure, internal control andsystems.
Employee strength in terms of numbers, qualification and experience.
Number of certified energy auditors.
Maximum number of projects handled at a time.
Annual turnover from the ESCO/energy management business.
Profit margins of the ESCO business.
Overall financial strength as reflected by the capital structure and debt servicingindicators like net cash accruals/total debt
Receivables management.
Financial flexibility arising from access to cash-flows/profits from other business.`
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A 100 point scale has been devised based on the above parameterswith a 20% weight-age given to Business Risks, 40% weight-age toOrganizational Risks and 40% to Financial Risks
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CRISIL has assigned a CRISIL-BEE Grade 1 to Honeywell Automation IndiaLimited, which indicates Very High ability of the graded energy servicecompany to undertake energy efficiency projects.
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Out toBid
Client develops the project
Bidding required as required by the government (in case of agovernment funded project)
RFQ Interested ESCOs submit their corporate resumes, business
profiles and initial plan
Short-listing
3-5 companies are shortlisted by the client
RFP
Shortlisted ESCOs are asked to give detailed explanation ofthe project Minimum six weeks of time to compile the report
Proposals are reviewed by the client ESCO with best possible solution for energy project is
selected
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Feasibility Studies and Analysis Engineering Designs
Providing or Arranging Financing
Project and Construction Management Purchase and Installation of Equipment
Training
Maintenance of Efficiency Measures
Monitoring of Project Performance
Administration Services
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The International Performance Measurement and Verification Protocol (IPMVP) is thestandard M&V guideline for determining actual savings created by an energymanagement program
IPMVP Option A Retrofit Isolation: Key Parameter Measurement Savings aredetermined by field measurement of the key performance parameter(s) which define theenergy use of the ECMs affected system(s). Parameters not selected for fieldmeasurement are estimated.
IPMVP Option B Retrofit Isolation: All Parameter Measurement Savings aredetermined by field measurement of the energy use of the ECM-affected system.
IPMVP Option C Whole Facility Savings are determined by measuring energy use at
the whole facility or sub-facility level.
IPMVP Option D Calibrated Simulation Savings are determined through simulationof the energy use of the facility, or of a sub-facility. The simulation model must becalibrated so that it predicts an energy pattern that approximately matches actualmetered data.
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The savings in energy costs are often used to payback the capital investment of the project over afive- to twenty-year period
A common way to calculate energy savings is to
measure the flows of energy associated with theECM, and then to apply spreadsheet calculationsto determine savings.
Large capital improvement like Up-gradation of Mechanical and ElectricalSystems can be financed through energy savings project
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As per the statistics of the Rashtrapati Bhawan, during January-June 2009, 78.95 Lakh
units of electricity was consumed in the President's Estate. Due to the energy efficient
measures, the corresponding electricity consumption from Jan-June 2010 has come
down to 64.03 Lakh units, which is a reduction of 14.92 Lakh units saving more than
Rs. 90 Lakh
Honeywell Automation India Limited awarded the project for implementing ECM
Energy consumption reduction by 23% and Earnings as 60% of the savings
Energy efficiency has been introduced largely in the areas of efficient lighting and in
the use of star rated air-conditioning systems
ISO 14001:2004 certification which sets the standards for Environmental Management
Systems that are now in place in the 340 acre President's Estate
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http://www.fepc.or.jp/ http://www.cea.nic.in/reports/planning/report_85_pul_coal.p
df
http://www.cea.nic.in/thermal_rnm.html
http://www.fujielectric.com/company/tech/pdf/r51-3/r51-3.pdf
ACCREDITED ENERGY SERVICE COMPANIES byBureau of Energy Efficiency, Ministry Of Power
Current state of ESCO activities in Asia: ESCO industrydevelopment programs and future tasks in Asian countries byChiharu Murakoshi and Hidetoshi Nakagami, JyukankyoResearch Institute, Japan
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