Case Study & Initiatives

SO2 & NOx Control

G.VenuGM (Project Engineering)NTPC Ltd

- Overview - NTPC Perspective- Technology Scan- Environmental Action Plan

SOxNOx Conference 21/09/2017 New Delhi

Case Study & Initiatives

SO2 & NOx Control

Overview

Pollution is the introduction of contaminants into the natural environment that causeadverse change. Pollution can take the form of chemical substances or energy, such asnoise, heat or light.

India: Emission % by sourceEmission (%) Power Industry Residential/Others Transport

SO2 46 41 6 7

NOx 20 20 10 40

PM 17 9 47* 17

CO - 10 11 75* Wood Burning/Brick Kiln/Generator/Construction/Waste Burning etc.

Nitrogen dioxide and nitric oxide are referred to together as oxides of nitrogen

(NOx). NOx gases react to form smog and acid rain as well as being central to

the formation of fine particles (PM) and ground level ozone, both of which areassociated with adverse health effects..

Sulphur dioxide (SO2) is one of a group of highly reactive gases known as

“oxides of sulphur”. SO2 is linked with a number of adverse effects on the

respiratory system and other environmental issues. It is an important

industrial emission gas which causes several difficulties in the environmentlike acid rain.

Indian Power Scenario: 2016-17India: 329 GW

NTPC : 51,410 MW Capacity (16%)

NTPC Generation: 250 BU (22%)

NTPC Coal PLF 78.6%

India 329 GW

Thermal 12th PlanTarget- 88 GW

Addition- 99 GW

Renewable 2016-17Target-17 GW

Addition-11 GWShortage-6 GW in Solar

Coal- 546 MMT

Sector Wise (GW & BU) 2016-17

Sector GW % BU %

Central 80 25% 433 38%

State 104 32% 351 30%

Private 143 43% 370 32%

Capacity Type (GW): Total 329 GW

Thermal 220 67%

Nuclear 6 2%

Hydro 45 14%

Renewable 57 17%India Generation (BU)

@ PLF 60% (Th)

Total 1154 2016-17

Thermal 931 81%

Hydro + Nu 141 12%

Renewable 82 7%

Coal: Capacity Sector Wise (GW)

(4.8 BU/GW)

Total 194 100%

Central 55 28%

State 65 34%

Private 74 38%

Renewable Energy 2016-17 (1.4 BU/GW)

Description Capacity, GW Generation, BU

Total 57 GW 100% 82 BU 100%

Wind 32 56% 46 56%

Solar 12 21% 14 17%

Bio 8 14% 14 17%

Small Hydro 5 9% 8 10%

Peak Demand 2016-17

Demand Met Deficit %

159.6 GW 157 GW (-) 2.6 (-) 1.6

1142 MU 1135 MU (-) 7 (-) 0.7

Private Utility Capacity (MW)

Tata Power 10,496

Adani Power 10,440

DVC 9,445

Reliance Power 6,000

GMR 4,400

Lanco Infratech 3,460

CLP 3,000

Torrent Power 1,647

PSU Utility Capacity (MW)

NTPC 51,410

NHPC 9,847

DVC 9,298

NPCIL 4,500

NLC 4,298

SJVN 1,959

Renewable: Capacity Sector Wise (GW)

(1.4 BU/GW)

Total 57 100%

Central 2 4%

State 0 0%

Private 55 96%

Generation (BU) All India

Period 2017 Conventional Renewable

Total Generation

(BU)

April 103.16 6.93 110.09

May 107.29 8.66 115.95

June 97.52 10.22 107.74

July 97.91 11.9 109.81

Total 405.88 37.71 443.59% 91.5 8.5 100

Thermal Plant: April to August 2017 Generation Data: Sector-wise

S.No Sector Installed

Capacity (MW)

Generation

(BU)

PLF (%)

1 Central 63,190 144 71.73

2 State 71,228 129 54.46

3 Private 85,015 151 56.01

Total 219,435 424 58.96

The emissions per unit of electricity from Thermal Plants are estimated to be in therange of 6.94 to 7.20 g/kWh for SO2, and 4.22 to 4.38 g/kWh for NOx

Coal will be mainstay for Energy needs…

2014-15:SO2 Levels 2014-15:NOx Levels

2009--2015-SO2 Levels 2009-15:NOx Levels Delhi

Cape Town

UN Framework Convention for Climate Change (UNFCCC)

India notified revised Environmental Norms on 7th December 2015 (before COP-21)Since RE is not available 24x7, India has to look for adequate balancing power from coal as India does not have enough gas and oil resources.

The twenty-first session of the Conference of the Parties (COP) and the eleventh session of the Conference of the Parties serving as the meeting of the Parties to the Kyoto Protocol (CMP) took place from 30 November to 11 December 2015, in Paris, France.

India: Renewable Generation expected by 2022 (20%)

Description Sulphur Dioxide (SO2) Oxides of

Nitrogen (NOx)

Mercury

(Hg)

Installation Period (mg/Nm3)

(For < 500 MW

size)

(mg/Nm3)

(For > 500 MW

size)

(mg/Nm3) (mg/Nm3)

Installed before December

31, 2003

600 200 600 0.03

Installed after 2003 and up to

Dec, 2016

600 200 300 0.03

Installed after December,

2016

100 100 100 0.03

Suspended Particulate Matter

(SPM)

New Norms

(mg/Nm3)

Installation Period

Installed before December 31, 2003 100

Installed after 2003 and up to 31

Dec, 2016

50

Installed after 31 December, 2016 30

New Environmental Norms for Particulate emissions, SO2, Nox & Mercury (07/12/2015)

Mercury Emission Control:

No matured or commercial technology

is available for mercury emission

control now. However, the limits of

Mercury emission shall be met

through above methods like ESP/ESP

R&M and future FGD in all units.

National Ambient Air Quality Standards

(2009)

Pollutant Time weighted Average

Concentration in Ambient Air

(microgram/cum)

SO2 Annual24 hours

5080

NOx Annual24 hours

4080

Case Study & Initiatives

SO2 & NOx Control

NTPC Perspective

NTPC Operating Plants NO. OF PLANTS

CAPACITY (MW)

NTPC Owned

Coal 20 38,755

Gas/Liquid Fuel 7 4,017

Hydro 1 800

Renewable(Solar + Wind)

12 910

Sub-Total 40 44,482

Owned By JVs/Subsidiaries

Coal & Gas 9 7,216

Operating Plants Total 49 51,698

Ongoing Projects as on 14.07.2017 Capacity (MW)I. NTPC owned:

A. Coal Based Projects

1. Bongaigaon, Assam 250

2. Barh-I, Bihar 1,980

3. Lara-I, Chattisgarh 1,600

4. North Karanpura, Jharkhand 1,980

5. Kudgi-I, Karnataka 800

6. Gadarwara-I, Madhya Pradesh 1,600

7. Solapur, Maharashtra 660

8. Darlipalli-I, Odisha 1,600

9. Tanda-II, Uttar Pradesh 1,320

10. Khargone, Madhya Pradesh 1,320

11. Telangana Phase-I, Telangana 1,600

Sub Total (A) 14,710B. Hydro Electric Power Projects (HEPP)

12. Tapovan Vishnugad, Uttarakhand 520

13. Lata Tapovan, Uttarakhand@ 171

14. Rammam Hydro, West Bengal 120

Sub Total (B) 811C. Renewable Projects (Solar/Small Hydro)

15.Singrauli Small Hydro 8

16. Rojmal Wind 10

Sub Total (C) 18

Total I: (A)+(B)+(C) 15,539

II Projects under JVs & Subsidiaries

Coal Based Projects

18. Nabinagar- JV with Railways, Bihar 500

19. Nabinagar, JV with BSPGCL, Bihar 1,980

20. Meja, JV with UPRVUNL, Uttar Pradesh 1,320

21.Rourkela NSPCL 250

22. Durgapur NSPCL 40

Total II 4,090

III Total On-Going Projects as on 14.07.2017 (I)+(II) 19,654 MW

Operating Plants: 51,698 MWPlants Under Implementation: 19,654 MW

Plants under Tendering: 4,996 MW (Thermal: 3720 + RE : 1276)

Total Capacity: 76,348 MW

NTPC Portfolio

Super Critical is Central to NTPC’s Clean Power Focus

Thermal Efficiency development of NTPC units

NTPC Initiatives & Future PlansCoal will be mainstay for India. Accordingly, NTPC is working towards a balance of Technology Mix & Portfolio Mix havingdiversified fuel mix with 600 BU Generation by 2032 for reduction of emissions and resulting Environmental Protection.

Tenders for all new coal plants like Patratu (3 X 800 MW)/Talcher TPP (2 X 660 MW)/Singrauli-III (2 X 660 MW) include FGD &SCR Systems for limiting SO2 & NOx emissions.

Technology Mix Portfolio Mix

- Higher Efficiency- Lower Aux Power

- Higher Parameters- R&M of units

- SC/Ultra Super Critical units- IGCC/Oxyfuel

- Advanced Ultra SC (R&D)- Retrofit of Pollution Control Systems

- (FGD/CM/SCR/SNCR)

- Renewable EnergySolar PV Plants

Roof Top Solar PV PlantsSolar Thermal PlantWind Power PlantGeo Thermal Plant

Small Hydro- Hydro Projects

- Nuclear Projects

Other areas:- Wind + Solar Hybrid Plant @ Kudgi- Waste to Energy Plants- Biomass Co-firing

Portfolio by 2032 GW %

Coal 85 65.4

Gas 6 4.6

Hydro 5 3.8

Solar + Other RE 32 24.7

Nuclear 2 1.5

• During early 2016, NTPC Team visited USA, Europe & Japan to get feedback on varioustechnologies for SO2 &NOx controls. Apart from Manufacturers, NTPC Team also visited12 Coal fired Power Stations abroad wherein Emission Control Systems like FGD, SCR,SNCR, REACT etc. were installed.

• NTPC Team collected feedback on Technologies and Performance feedback along withO&M issues. NTPC Team also gathered data about the Environmental Normsimplementation period, schedule as well as shut down of unit required etc.

• The above visits, discussions with various Technology providers and internal technicalanalysis had confirmed the need for installation of suitable technologies likeFGD/SCR/SNCR/CM for control of SO2 &NOx from the Coal fired Power Plants of NTPC.

• Based on the above, NTPC has selected the appropriate technology and also taken up inFebruary 2016 various Policy Advocacy issues on implementation of NewEnvironmental Norms with MOEF &CC, MOP, CEA & CERC. A number of meetings in thisregard was also attended by NTPC and discussed all implementation issues.

NTPC Efforts & Policy Advocacy

Major issues taken up by NTPC (February 2016)

• Exemption of norms for SO2 & NOx Emission limits for units commissioned prior to 2003.

For existing units, serious concerns exist with regard to space availability for retrofit of FGD andDe-Nox Systems as no provision was required to be kept as per Environmental Clearances forthese units.

• Proven Technology for NOx limit of 100 mg/Nm3.

Provenness of SCR Technology for high ash Indian coals are yet to be established. Further,without SCR/SNCR Technology, the limit to be relaxed to 450 mg/Nm

3for unit installed after

2003.• Staggering of implementation period and consideration of 5-10 years for implementation as

per practice in some countries like South Africa.

• Allowing fixed charge recovery for extended shut down for retrofitting FGD/SCR/ChimneyLining for about 6 months per unit.

• Compliance to be considered on Station Level and not on Unit level for emission limits.

• With stringent limits of PM, SO2 & NOx Emission limits, Chimney height norms to be relaxed.

• Issues related to additional costs involved and impact on tariff and request for Fund support.

Case Study on

SO2 & NOx Emission Control Technologies

The IEA’s June 27–released World

Energy Outlook 2016 special report,

“Energy and Air Pollution,” says that

between 2005 and 2015, coal-fired power

generation worldwide expanded 34%, but

total power sector emissions over the

same period plunged: SO2 by 55%,

NOx by 34% and PM2.5 by 32%.

The World’s Power Sector emitted a third of global sulphur dioxide (SO2) emissions,14% of nitrogen oxides (NOx), and 5% of total particulate emissions (PM2.5), but thoseemission values have fallen drastically over the last decade even though coal powergeneration has seen a surge, the International Energy Agency (IEA) said in a newreport.IEA attributes the reduction in emissions principally due to the “Introduction ofEmission Standards for Coal-fired Power Plants, which led either to the use of coal witha lower sulphur content or to the installation of Pollution Control Technologies” overthe last 10 years.

Spray Dryer Absorber (SDA)Circulating Dry Scrubber (CDS)Novel Integrated Desulfurization (NID)

Sulphur Dioxide (SO2) Emission Control Technologies

Beside above there are other technologies such as Sorbent Injection, Multi-pollutant Control Technology.

Parameters WET Limestone FGD DRY FGD (SDA/CDS/NID)

Commercially Available Range ~ 1,100 MWe~ 300-400 MW single absorber. For higher

size units multiple absorbers.

SO2 removal efficiency Up to 99 % up to 99 % (90-95 % for SDA)

Installation Cost (Considering ZLD & Chimney lining cost)

High Low

Operating Cost Moderate High

Sorbent consumptionCaCO3 (limestone)

SR 1.05CaO / Ca(OH)2

SR 1.3 – 1.5

Sorbent costs (Rs/ton) ~2000 ~6000

Water consumption1.0 with GGH

1.4 without GGH0.7

Auxiliary Power ConsumptionHigh with GGH

Moderate without GGH Moderate

Flue gas temperature at FGD outletSaturation temperature

50 – 60 °C (Without GGH)75 – 85 °C

SO3 removal < 40 % > 98 %

Condition of existingstack

Existing stack has to be modified . Long outage for retrofit

Existing stack can be usedwithout modification

Brief comparison of De-SOx Technology

21

Sea Water FGD

Preferred option for Coastal Plants except in Japan

METRIC UNIT

SO2 Emissions ≤ 35 mg/Nm3

Particulate Matter Emissions ≤ 5 mg/Nm3

Ammonia Slip ≤ 3 mg/Nm3

Ammonia Recovery Rate

≥ 99%

Ammonia based FGD System

LIMESTONE PROCESS AMMONIA PROCESS

Absorbent Limestone Ammonia

By-Product GypsumAmmonia Sulfate

Fertilizer

SO2 Removal Efficiency

≥ 95% ≥ 99%

Waste Water 25 kg/hr /MW None

CO2 Emissions 0.7 t/t SO2 Removed None

Comparison Between Limestone & Ammonia Process

Multi-Pollutant Control (MPC) Systems

MPC Systems*

Wet Scrubbing Dry TechnologiesNon-Thermal Plasma

TechnologiesGas Phase Oxidation

Technologies

Air borne ProcessNeuStream

ProcessSkymine Process(High Water Consumption)

ReACTSNOX

EBFGTECO

(High Power Consumption)

EPS SystemLextranLotoX

(High Power Consumption)

Multi-Pollutant Control system remove two or more of the principal regulated pollutants (SO2, NOx, PM, Hg and CO2) in a single reactor or a single system designed for the purpose

*Source: IEA Report

NTPC’s Plan for implementation of SO2 Emission Control Technology

Based on meetings/discussions with various SO2 emission control technology supplier and visit to various

installations worldwide it has been concluded that Wet FGD may be most suitable technology for Indian

conditions.

De-SOx technologies

For Indian conditions wet FGD will be more suitable Sea water FGD will be suitable in case of coastal plant

As NTPC is already installing Wet FGD in two of its projects i.e. Bongaigaon (3 X 250 MW) & Vindhyachal (1 X 500 MW).

Based on experience of the design of two projects, planning for FGD at various NTPC stations are on with respect to following issues:

Availability of Space for installation of various FGD system components.

Availability of Lime stone.

Disposal of by-product.

Modification in the existing duct layout.

Modification in the Chimney lining.

Technologies to limit Nitrogen Oxide (NOx) emission

There are mainly three NOx control technology namely,

Combustion Modification(CM)

Selective Non-Catalytic Reduction(SNCR)

Selective Catalytic Reduction(SCR)

These technologies can be implemented individually/ combined as per the requirement

Description In Combustion Post Combustion

Technology Combustion Modification SNCR SCR

NOx Emission Control Measures

Low NOx Burner

Staged combustion throughvarious type of over fire airdampers

NOx reduction through reagentinjection:Aqueous ammonia or Ureasolution

NOx reduction through reagentinjection in presence of catalyst:Catalyst type:Plate/ Honeycomb/CorrugatedReagent:Anhydrous/ Aqueous or Ureaderived ammonia

Reduction Efficiency 20 – 60 % 25-40 % 90 % & Above

Installation Cost Low Moderate High

Operational CostNone

High (mainly reagent cost)High (Aux power, reagent

cost & catalyst replacement)

Operating Temperature Range

N/A 870° to 1100°C 300° to 400°C

Brief comparison of Technologies to limit Nitrogen Oxide (NOx) emission

The suitability of SCR/SNCR technology for Indian Coal with high ash and abrasive ash is not proven

Case Study on SO2 & NOx Emission Control

Action Plan

SO2

Emission Control

Worldwide Plant Visit

& Feedback

Analysis & Policy

Advocacy

Technology, Phasing Plan &

Strategy

Action Plan &

Approval

Tendering & Implementation

NOx

Emission Control

Worldwide Plant Visit

& Feedback

Analysis & Policy

Advocacy

Technology, Pilot Testing & Strategy

Tendering & Implementation(after Pilot Test)

EOI forLimestone Supply &

Gypsum Sale

Boiler OEM support for Combustion Modification

CM Pilot Test

300/100 mg/Nm3

600 mg/Nm3

Wet Limestone FGDLot-1: UC & up to 5 years

Lot-2: 5 to 15 yearsLot-3: >15 years

USAEurope

UKJapan

SCR/SNCR

Compliance Target progressively

as per RPC guidelines byDecember 2022

NTPC Plant

Operating Data

Collection

NTPCPlant

Operating Data

Collection

NTPC48 GW Coal fired Plants(Additional 14 GW after CERC clearance)

MOEFCERCCEAMOPRPC

S.No Description Capacity(MW)

NIT Remarks

FGD under operation/implementation/tendering 5,250 Done VSTPP-V FGD Commissioned

Summary of FGD Tendering Plan

1 Lot-1A (ICB Mode)(Units Under Construction & Less than 5 years in operation)

17,440 30/06/2017

2 Separate Tenders (ICB Mode)(Khargone & North Karanpura)

3,300 17/07/2017

3 Lot-1B (DCB Mode)(Units less than 5 years in operation)

7,210 31/07/2017

4 Lot-2 (DCB Mode)(Units between 5 to 15 years in operation)

14,670 Oct-Dec 2017(Plan)

5 Lot-3 (DCB Mode)(Units more than 15 years in operation)

14,580 - (NIT after CERCclearance)

Total 62,540 MW

Wet Limestone based FGD System Plan: NTPCAfter detailed deliberations and meetings with CEA, CERC, RPCs and Ministries, NTPC formulated an ActionPlan for control of SO2 & NOx which was cleared by NTPC Board in March 2017 and subsequently developedan implementation plan.

S.No Activity detail Expected Time Schedule Remarks

1 Distribution of common test procedure to EOI Applicants after

approval of procedure and investment note sheet15.10.16 Distributed on 17.10.16

2 Publishing of Notice for interesting applicants other than EOI for

pilot test20.10.16 Published on 20.10.16

3 Agreement signing with Various willing applicants and allocation

of stationDec 2016 Discussions completed. 11 Applicants

selected

4 Engineering of Pilot test Sept 2017 Approximately 6 months required.

Start of Test expected by September 20175 Supply of material

6 Erection of Pilot plant

7 Integration with the unit (Depend on shut down of unit)*

8 Collection of test data and Analysis of the test result March 2018 6-12 months continuous test is required.

9 Declaration of outcome of the test June 2018 Final Results by June 2018 & then Action

Plan

De Nox Action Plan:

In order to check the suitability of SCR technology for high ash and abrasive ash, SCR pilot test studies is beingundertaken at NTPC running stations to check the suitability of SCR system for High ash Indian Coal and resultsof same are expected to come by March 2018. Planning/strategies shall be decided after the SCR pilot testresult.

De Nox Pilot plant Testing Schedule:-

NOX Emissions Control

SCR/ SNCR system allocated to NTPC station for carrying out pilot test of SCR/ SNCR

system

Total- 11 SCR tests and 3 SNCR tests

S No Name of Applicant SCR/SNCR Test Allocated NTPC Station

1 BHEL 2 nos. SCR test Simhadri (U#1)

2 GE- Alstom 1 no. SCR & 1 no. SNCR Vindhyachal (U#13)

3 MHPS 1 no. SCR test Sipat (U#4)

4 Termokimik Italy 1 no. SCR Singrauli (U#6/7)

5 Shanghai 1 no. SCR Talcher (U#6)

6 Andritz 1 no. SCR Korba (U#7)

7 ERC 1 no. SNCR Korba (U#7)

8 Yara Norway 1 no. SCR & 1 no. SNCR Rihand (U#4)

9 Thermax B&W 1 no. SCR Ramagundam (U#7)

10 Doosan 1 no. SCR Kahalgaon (U#7)

NOx emission control: Tentative Plan (after Pilot Test results)

De-NOx Plan-NTPC131 Units

60 GW

Limit: 600 mg/Nm3

Combustion Modification (CM)for units installed Before 2003

52 units/17 GW

Limit: 100 mg/Nm3

SCR/Hybrid system for units installed after Jan 2017

(planned after successful SCR pilot test)

35 Units/22 GW

Limit: 300 mg/Nm3

CM + SNCR for units installed Between 2004 to Dec 2016

(planned after successful SNCR testing)

44 Units/21 GW

SCR De-NOx system in Patratu (3 X 800 MW) will be ordered under EPC for compliance of New Norm.SCR included in future tenders of TTPS-III (2 X 660 MW) & SSTPP-III (2 X 660 MW)

Total 159 Units of 65 GWPhasing out 25 Units of 2.4 GW

SCR Tendering done in Patratu (3 X 800 MW)

Coal

• USC/AUSC Units

• CCS & Utilisation

• Flexibilization

• Pollution Control

• Ash Utilization

Renewable

• Wind & Solar

• Battery Storage

• Bio-Mass

• Geo-Thermal

Hydro & Nuclear

• Hydro

• Pumped Storage

• Nuclear• Electric Vehicles

• Charging Stations

• Storage Solutions

• Manufacturing

• EPC Solutions

EV

Storage

Renewable

EPC

• WtE Plants

• Energy Conservation

• Green Buildings

WtE

EC

GB

Future Business Areas

धन्यवादgvenu@ntpc.co.in

Opportunities to reduce emissions !