Vedanta Aluminium Ltd.
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Transcript of Vedanta Aluminium Ltd.
CAPTIVE POWER PLANT ( 9x135MW )
VEDANTA ALUMINIUM LIMITED, JHARSUGUDA
INDIA
ODISHA
PLANT SITE
CPP VAL – PLANT LOCATION
04/10/2023
AWARDS & RECOGNITION
CPP-VAL has been Awarded 1st Prize in “National Energy Conservation Award-2012” by Bureau of Energy Efficiency in Thermal Power Sector.
CPP-VAL was Awarded 2nd Prize in “National Energy Conservation Award-2011” by Bureau of Energy Efficiency in Thermal Power Sector.
CPP- VAL along with Smelter is Awarded by Frost & Sullivan Green Manufacturing Award-2013.
CPP-VAL is certified ISO-50001:2011 Energy Management System (EnMS).
CII award for “Excellence in Energy Management-2013”
PLANT PROFILE
Largest Captive Power Plant in India
Fastest completed CPP in India.
Water Source – Hirakud Reservoir
Coal Source- Mahanadi Coal Fields
High Concentration Slurry Disposal
Hybrid ESP with SPM level < 40mg/Nm3
An ISO 9001, 14001, 50001 & OHSAS 18001 Certified Company
04/10/2023
04/10/2023
ELECTROSTATIC PRECIPITATORAN INTRODUCTION
04/10/2023
ESP OVERVIEW
04/10/2023
PROCESS OF PRECIPITATION
INITIAL PARTICLE CHARGING
CORONA DISCHARGE
PARTICLE COLLECTION & REMOVAL PARTICLE CHARGING
GAS IONIZATION
OLD ESP TO HYBRID ESP STEP TOWARDS SUSTAINABILITY
CHALLENGE
SPM levels of all the Units were slightly higher than the standard norms.
Anticipated more stringent norms of emissions (< 50 mg/Nm3) to be enforced in near future.
STATUTORY ENVIRONMENTAL NORMS
Apr-11 May-11 Jun-11 Jul-11 Aug-11 Sep-11 Oct-11 Nov-11 Dec-11 Jan-12 Feb-12 Mar-12
0
40
80
120
160
200
136
105 113125 126 119 125 127
11199 92
81
AVERAGE SPM (2011-12)Average SPM
CHALLENGE
CPP was designed for coal of 3300 kcal / Kg and 41 % ash.
The average GCV and Ash content of used coal was 2500 kcal / kg & ash of 50-55 %.
Ash has a high resistivity.
Characteristics of coal and ash not consistent with the design.
Reduction in the collection efficiency of ESP’s.
COAL & ASH CHARACTERSTICS
04/10/2023
BRAINSTORMING&
IDEA GENERATION
CAUSE & EFFECT
MATERIALMACHINE
METHODSMEN
High Ash
High resistivity
Distribution screen
Electrode alignment PF Coal/Ash grain size
Ash Evacuation
Control of O2
Uniform coal feeding
Conveying air flow/pressure
Rapping cyclesTemp monitoring
ESP Controllers
Slurry disposal/SILO level control
Maintenance practices
Ash evacuation cycle timing
Size of Fields
SPM around 100 mg/Nm3
High flue gasvolume
Transformer sizingHigh SCC
ALTERNATIVES CONSIDERED
a) Continue to run with present ESPs with ammonia dosing:
b) Going for dual conditioning system Ammonia
c) Going for Retrofitting of current ESP with addition of extra fields
d) Retrofit the ESP and install a fabric filter plant with high temperature bags:
04/10/2023
HYBRID ESPAN INTRODUCTION
CONCEPT OF HYBRID ESP’s
ESP-FF hybrid precipitator is a combination of ESP & Fabric filter.
It has an advantage of both ESP & Fabric filter.
Gases are separated from dispersed particles by passing it through fabric medium.
Particles that are not able to penetrate will remain on the surface of medium so called “Filter cake”.
90% dust collection is done by ESP fields rest by bag filters.
FABRIC FILTERS
Fabric filters has one or more compartment containing cylindrical fabric bags.
Compartment system generally contain multiple rows of bags.
Normally service life of fabric filter is 3 to 4 years.
Fabric filter system is fitted with high temperature bags - Polyphenylenesulphide (PPS).
Low temperature bags - Polyacrylonitrile (PAN) may also be used.
04/10/2023
HYBRID ESP - THE PROJECT
HYBRID ESP- THE PROJECT
VAL-CPP has undergone Bag filter modification in a phased manner.
Last two fields of ESP were removed and bag filter was installed.
Modification completed for all the 9 units.
EPC contractor – SEPCO.
HYBRID ESP- THE PROJECT
Project Zero date – Nov-2011.
Manpower involved in each unit is around 300.
53 m3 of concreting was done.
454 tones of steel erection.
Timely completion of the project as per schedule.
DISMANTLING OF OLD ESP
Top penthouse & monorail Hoist are dismantled.
Outer roof along with Inner roof are dismantled with insulator compartments.
Collecting plates along with Emitters are separated out along with suspension frame & rapping mechanism.
Distribution plates with hopper baffles & recti formers are dismantled.
Total 2700 Tones of structure was dismantled from Old ESP.
DISMANTLING OF OLD ESP
Dismantling of Flue gas duct before & after ID Fan.
ID Fan dismantling along with bearing housing, Impeller motor & support structure.
Rectifier Transformers along with cables & insulators are dismantled.
ERECTION OF HYBRID ESP
Erection of outer & inner roof with roof beam.
Commissioning of Air tanks & guide equipment.
Erection of gas path system, pre coating pipelines , cage & bag filters arrangement.
ID Fans support structure installation.
Erection of bypass duct & dampers.
ERRECTION OF HYBRID ESP
Installation of Flue gas duct along with motor dampers.
Installation of ID Fans with Casing ,Impeller , Rotor, Bearing house & Expansion Joints.
Installation of new Compressors with driers & filters.
Insulation of total System.
GLIMPSES OF HYBRID ESP
PROJECT SAFETY
COMMIT TOWARDS
SAFETY
ZERO LOSS OF TIME DUE
TO INJURY
ZERO FATALITY
DURING THE PROJECT
SAFETY TRAININGS &
DRILLS DURING
PROJECT
04/10/2023
PERFORMANCE&
EFFICIENCY
HYBRID ESP- AFTER COMMISSIONING
Fabric filter system is fitted with high temperature bags - Polyphenylenesulphide (PPS) were considered taking the worst scenario.
The performance of the plant is good with emission values consistently
below the 40mg/Nm3.
Filter Plant Type : Pulse Jet Filtration Velocity : 1.04 m/minBag Material : PPS (PTFE Impregnation Treatment)Bag Quantity : 5002Bag Specification : Dia 130 X 8065Injection Pressure : 0.25 -0.35 MPa
HYBRID ESP- PERFORMANCE
Reductions in SPM < 40 mg/Nm3.
Improvement in collection efficiency and stable operation of ESP’s.
Reduction in energy consumption of ESP’s.
Increase in life of bag filters due to small pressure difference across filter bags.
Maintenance friendly.
OPTIPOW pulse valve adopted to guarantee high efficiency and for. stable and reliable ash removal.
The operation of the equipment is controlled by PLC through the temperature, pressure differential pressure, current, voltage and the travel feedback signal.
HYBRID ESP - PERFORMANCE
Nov-11 Dec-11 Jan-12 Feb-12 Mar-12 Apr-12 May-12 Jun-12 Jul-12 Aug-12 Sep-12 Oct-12 Nov-12 Dec-12 Jan-13 Feb-13 Mar-13 Apr-13 May-13 Jun-13
0
40
80
120
160
200
127111
99 9281
71 6655 47 41 45
24 22 20 23 25 26 28 24 26
Average SPMAverage SPM
Before
After
04/10/2023
HYBRID ESPO&M PRACTICES
HYBRID ESP – BAG CLEANING SYSTEM
Fiber filter adopts differential pressure control mode for cleaning the ash deposited on bag.
Differential pressure of dust collector is the criterion for ash removal from bag filters.
Ash removal will not stop until differential pressure of bag filter drops below the set value.
When the differential pressure of the dust collector surpasses a setting value, PLC will transmit a signal to the pulse controller, then the pulse valve will open, the compressed air in the air tank will instantly release and enter into the filter bag. The dust cake accumulated on the outside will break and get loose and then drop into dust hopper when the filter bag expands
HYBRID ESP – OPERATION
Amount of moist, acid and sticky dust collected on the filter bags during the start-up phase to be minimized.
The FF shall not be connected to the flue gas stream until coal starts to be fired in the boiler and the thermal power achieves 80% above the total thermal power.
The flue gas temperature ought to be at least 20 above the acid dew ℃point.
Main monitoring Screen
HYBRID ESP – MAINTENANCE
Regular checking of differential pressure of dust collector.
Monitoring of gas flow.
Checking the compressed air of pulse cleaning dust collector.
Checking nozzle compartments and dust hopper for dust accumulations.
When about 10% of the bags in a compartment have been blocked, all damaged bags shall be replaced.
BEST PRACTICES
The most common and usual problem with pulse injection FF is the water and oil content in compressed air which is used for ash discharge from filter bag.
The water and oil permeates the filter material, wetting the dust, which chokes the filter bag.
This increases the pressure drop and finally the bag is to be replaced.
HIGH QUALITY OF COMPRESSED AIR
BEST PRACTICES
During commissioning pre coating of bag filters is required before taking the system into service.
After long shutdown of the unit or if bag purging is done in shutdown condition Pre-coating is required.
PRE COATING OF BAG FILTERS AFTER LONG SHUTDOWNS
BEST PRACTICES
In case of tube leakages unit shutdown should be taken immediately, otherwise pressure drop in bags may increase.
In case of If Oil Gun is taken into service the bag filters need to be bypassed.
During light up or Shutdown of the Unit bag filters will only be taken into service after removal of Oil Guns.
IMMEDIATE SHUTDOWN OF UNIT IN CASE OF TUBE LEAKAGES
THANK YOU