3. 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”
4. 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
10/8/2013
8. OLD ESP TO HYBRID ESP
STEP TOWARDS SUSTAINABILITY
9. 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
136
105
113
125 126 119 125 127
111
99 92
81
0
40
80
120
160
200
Apr-11 May-11 Jun-11 Jul-11 Aug-11 Sep-11 Oct-11 Nov-11 Dec-11 Jan-12 Feb-12 Mar-12
AVERAGE SPM (2011-12) Average SPM
10. 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
12. CAUSE & EFFECT
MATERIAL
MACHINE
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 gas
volume
Transformer sizing
High SCC
13. 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:
15. 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.
16. 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.
18. 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.
19. 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.
20. 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.
21. 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.
22. 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.
23. 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.
27. 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/min
Bag Material : PPS (PTFE Impregnation Treatment)
Bag Quantity : 5002
Bag Specification : Dia 130 X 8065
Injection Pressure : 0.25 -0.35 MPa
28. 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.
31. 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
32. 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
33. 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.
34. 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
35. 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
36. 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
