engineering solutions for nox control in power...

This project is co-financed by the European Union and the Republic of Turkey Bu Proje Avrupa Birliği ve Türkiye Cumhuriyeti tarafından finanse edilmektedir

Technical Assistance for Better Air Quality by Transposing the Large Combustion Plants Directive (TR2010/0327.04-01/001)

Engineering solutions for NOx control in power plants

By Timo Anttikoski



• Content of the Presentation

– Combustion system NOx control solutions

– Case study from Finland

– Questions and answers



Combustion system NOx control systems

By Timo Anttikoski



Low NOx Wall Burner Systems Low NOx Tangential Systems Low NOx Arch Systems



• Dependable Performance – 6-lobe Opti-Flow nozzle has >50% more

peripheral exposure for devolatilization compared to round nozzles

– Improves Emissions, Erosion, Slagging, Turndown, and Boiler Performance

– Reliable Online Tuning

• Repeatable Controllability – Two air zones, three linear drives, for

independent Swirl & Airflow control

– Fixed Vane swirlers minimize binding

– Non-pitot Air Flow Measurement – Strong DP Signature, low clogging



Challenges: – NOx values in 0.55 – 0.6 range – Burner coking and fires in the burner – Eyebrows and furnace slag

Amec Foster Wheeler’s Solution: – Opti-Flow Nozzle with existing registers – De-spin assembly with existing scroll

Overall Results:

– NOx reduced to 0.35 – Cleaner combustion – no coking/slag – Led to Upgrade for 500 MW Output

Background: 440 MW Amec Foster Wheeler boiler firing western bituminous



Opti-Flow OFA Nozzle

– Elliptical for wide cross-flow area, good penetration

– Bellmouth reduces ΔP, allows for high penetration

– Single reliable track design for linear actuation

Dual Zone OFA – Inner zone fills first, then outer

annulus

– Maintains penetration at low OFA flows

– Improved control over conventional OFA ports



Past Experience: OUC Stanton Unit 2 – 450 MW Challenges:

– Constant Coal Variations Columbian-US Bituminous

– OFA Use Results in LOI > 8%, Ash Unsellable

Amec Foster Wheeler’s Solution: – Install OFA Opti-Flow Elliptical OFA

Ports, Utilizing Existing WB & WW Openings

– Install Opti-Flow LNB System

Overall Results:

– NOx reduced by 10 %

– LOI < 5.5%, Ash is Sellable



TLN 1 IN-WINDBOX

OFA

TLN 2 SEPARATED

OFA

TLN 3

IN-WINDBOX & SEPARATED OFA

OFA

Boundary Air

Separated OFA

w / Yaw & tilt

Separated OFA

w / Yaw & tilt

OFA

Coal

Boundary Air

Boundary Air

Coal

Coal

LFSC LFSC LFSC

− SINGLE level SOFA with tilt, yaw & velocity control.

− Longer Life DS Coal & Air Tips Provide Local Staging.

− Boundary Air Nozzles for Fireball Shape Control.

− Damper Upgrades Re-Establish Air Flow Control.

− Lower Furnace Stoichiometry Control.

Features/Benefits



• The Electric Charge Transfer System has the following advantages: − On-line, non-intrusive coal flow measurement

− Ethernet Connection for real-time display of information

− Automatic Air and Coal Closed Loop Control System



Adjustable Riffle

Distributors

Coal Distribution

Control Vanes Tower Distributor

Coal Flow

Balance Valves

Coal Distribution and Transport System



FW Dynamic

Classifier

Vertical Mill Upgrades Ball Mill Upgrades

Easy Roller

Removal

M-style Static

Classifier



• Testing and Field Services

• Technical Consultation

• Furnace & Airflow CFD Modeling

• Engineering Studies

• Supervision and Inspection

• Training



• Vortex Series Low NOx Burners

• T-Fired Low NOx (TLN) Systems

• Effective OFA

• Pulverizers

• Arch-fired Low-NOx Burners

• Coal Distribution Systems

• Alternate Fuels

• Engineering Services



Selective Catalyst Reduction (SCR)

By Timo Anttikoski



Catalyst

Airheater

Flow

Straightener

AIG

NH3 Tank

Aqueous NH3

System

Blower

Vaporizer

Clean Gas

To Stack

Static

Mixer(s)

In-Duct Heater

(Aqueous only)

Future

Catalyst

HOT AIR FROM IDHX

Ammonia/Air

Mixture To

AIG

COLD AIR TO IDHX

Econ Bypass



• Handling larger pieces saves time

• Working at grade instead of at final elevation improves safety

• Challenges include congested work areas, space for heavy lift cranes, space for module construction and laydown



• AIG is combined with two static mixers

• Proven design for difficult applications

• No tuning

• Improved Mixing for Temperature

• Minimizes impact of Combustion Issues

• Standard approach for utility boiler applications

• Not applicable for gas applications

• Flue Gas is sufficiently well mixed



• Used for upfront “what if” scenarios

• Used to optimize thermal mixing performance

• Conducted prior to physical model study

• Typically required on SCR projects

• Amec Foster Wheeler has in-house modeling expertise

• Experience with third-party modeling companies

• Extensive field verification testing



• The know-how and experience gained on previous utility SCR projects ...

• Contributes to the success of each new project

• Over 100 GWe of Low NOx

Combustion System and SCR

upgrades

• Over 130 SCR systems supplied,

30 high dust SCR units



AIG and

Mixers

Flow

Rectifier

Turning

Vanes

Future

Catalyst

Initial

Catalyst

Charge

Dampers for

Seasonal Bypass



AIG

and

Mixers

Future

Cataly

st

Initial

Cataly

st

Charg

e



Catalyst on Truck



Truck and

Rail Access

Maintained



• Design • Simple • Modular • Standarized • Sizing • Guarantees

HRSG SCR

//upload.wikimedia.org/wikipedia/en/b/bf/ModularHRSG-Picture.JPG

• Catalyst • Drop-in

• Monorail • Crane installation

• Pitch Size • 2 mm



HRSG SCR



Case Study Naantali SCR

By Timo Anttikoski



• Basic Data

– Client: Turun Seudun Energiantuotanto Oy (TSE)

– Location: Naantali Finland

– Contract price not disclosed

– Driving force of the project: Need to comply with NOx emission limits start of year 2016 (IED). NOx 180 mg/m3n, NH3 2 mg/m3n

• Scope of facility

– Sulzer once trough -type, Gebrüder Sulzer delivery year 1972 (420 t/h, 190 bar, 540 C)

• Project Schedule

– Award April 2014

– Erection May-August 2015

– Take over Dec 2015



Catalyst

Flow straightener

Turning vanes

Static mixers

Ammonia (NH3) injection grid

Airheater (NH3 system)

Future catalyst layer

Clean gas to stack



• Scope of supply – SCR-reactor with catalyst material

– Ammonia system designed to use water/ammonia mixture (25 % NH3)

– Flue gas ducts

– Soot blowing equipment

– Axial ID-fan(s)

– Supporting structures, service platforms, walkways, stairs and ladders

– Electrification and instrumentation

– Demolition and Erection

– Insulation

– Packing and freight

– Documentation

– Training, commissioning and trial run



Questions?

engineering solutions for nox control in power...

Documents