Emission Reducing Technologies for Boilers

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Emission Reducing Technologies for Boilers
Steamers
Alberta Research Council NOx SOx
Control Technologies Symposium April 9, 2008

William Testa Director, North American Sales Coen
Company / Todd Combustion
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Boiler Burner NOx Formation Fundamentals
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Sources of NOx

• Prompt NOx
• Thermal NOx
• Fuel NOx

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Methods of NOx Formation

• Fuel NOx formed from nitrogen contained in the
  fuel
• 0 of NOx in natural gas firing (no FBN)
• 50 of NOx in 2 oil firing (0.02 FBN)
• 80 of NOx in 6 oil firing (0.30 FBN)

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Methods of NOx Formation

• Thermal NOx (Zeldovich Mechanism) is a function
  of
• Peak flame temperatures (gt 2500 deg F) which
  breaks apart N2 molecules
• Available oxygen to bond with and form NOx
• Time to allow the reaction to occur
• 80 of the NOx from a natural gas burner

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Methods of NOx Formation

• Prompt NOx (Fenimore Mechanism) forms in
  sub-stoichiometric regions by
• Rapid reaction of fuel radicals with atmospheric
  nitrogen
• HCN and NH3 are formed as intermediate species
• Completed combustion causes these molecules to
  convert to NOx
• 20 of NOx from a natural gas burner

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Burners for Boilers Steamers
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Combustion Technology Solutions

• DAF
• Delta NOx
• QLN
• ULN Technology

• RMB
• Variflame
• Variflame II

Single Burner Applications up to 400 mm btu
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Technology Breakdown by NOx Levels Generated

• Rapid Mix / ULN Technology
• Ultra-Low NOx (9 20 ppm)
• Staged Gas
• Low NOx (20-80 ppm)
• Staged Air
• Low NOx (25 ppm)

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Rapid Mix Technology (9 - 15 ppm)

• 9 ppm
• No variable gas fuels.
• Light fuel oils only

6 ppm / Commercial 07 lt 150,000 /hr Cell design
run as one Furnace dependant
Todd RMB Burner
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Rapid Mix Burner

• Guaranteed Performance
• Natural Gas Firing
• 9 ppm NOx
• 25 ppm CO
• 3 ppm VOC
• 1 ppm SOx
• 2 Oil Firing (0.02 FBN)
• 78 ppm NOx
• 150 ppm CO
• 10 ppm VOC
• 30 ppm Sox
• NOx as low as 40 ppm firing Amber 363 Oil (0.002
  FBN)

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Rapid Mix Burner

• Burner Design
• 5 to 300 MMBtu/hr per burner
• lt 40 MMBtu/hr RMB (single zone)
• gt 40 MMBtu/hr DRMB (dual zone)
• gt 600 MMBtu/hr Two DRMB burners unison fired
• Operating Conditions (typ. boiler app.)
• Low RDL 8 to 10 in W.C.
• Low Gas Pressure required at the burner for MCR
  8 to 12 PSIG
• Design excess air 15 to 20
• Design FGR 25 to 30 (ambient air)
• Firing Rate Range 15 - 100

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ULN Technology (12 20 ppm)

• Coens QLN-ULN, DeltaNOx-ULN or DAF-ULN Ultra Low
  NOx Burners, with 10 flame stabilizing air
  supply
• NOx down to 15 ppm with FGR on gas
• Low VOC, CO, and particulate emissions
• Capacity of 20 to 440 mmBTU/hr
• High turndown of 101 on gas, 81 on oil
• Fires natural gas, moderately to widely variable
  BTU gas, and any distillate fuel oil

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Staged Gas Low NOx Technology (20 80 ppm)

• QLN / Staged Fuel
• Delta Nox / Staged Fuel
• Variflame II / Staged Fuel Air

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QLN

• - 30 ppm NOX w/o FGR
• 3 Fuel Zone
• Partial Premix
• Staged Fuel
• Doesnt fit all furnaces
• Light Oil Backup only

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QLN Performance Flame Shape

• Flame Diameter 2.1Burner Diameter
• Flame Length 8.0Burner Diameter

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DeltaNOx

• - Wide applicability
• 3 Fuel Zone
• Partial Premix
• Staged Fuel
• Narrow furnace limitations
• Limited Refinery Fuel Capability
• Up to 300 mm btu

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Delta NOx Burner Overview

• 60 ppm NOx for Typical Package Boilers
• 25 ppm NOx w/ FGR
• 15 ppm w/ ULN Technology
• Popular with OEMs Users
• Low Cost
• Best for Natural Gas
• Capable of Back-Up Oil Firing

DNX Natural Gas Firing
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Variflame II

• Refinery Fuels capable
• Up to 250 MMBTU/hr
• Heavy fuel staging
• Doesnt fit all furnaces
• Pressure Drop
• 5-12W.C.
• Typically 6-8.
• Higher DP is used for Flame Shaping

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Variflame II
Venturi Design Staging Air Fuel

• Staged Gas Injection

Tertiary Air
Staged Gas Ports
Secondary Air
Center Fired Gas
Primary Air

• Swirler imparts spin to primary air and center
  gas to create a stable recirculation zone

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Variflame II

• Performance Characteristics
• Turndown
• Typical Gas 8-101 and oil is 81.
• Stability
• Requires center-fired gas for stability.
• Zipper Tips requires less center-fired gas
• Enhances Flame Shaping
• Fuels
• Natural Gas, Propane, Refinery Fuel and any fuel
  oil
• Emissions
• gt 30 ppm NOx no FGR
• NOx with FGR as low as 16ppm
• Typically CO is 0 at capacity but will
  range up to 50ppm

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Low NOx Technology (25 ppm)
Todd Variflame
Coen DAF
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Variflame

• Very wide applicability
• Venturi Style burner
• Multiple Gaseous Fuels
• 2 - 6 Fuel Oil
• Orimulsion / Bitumen
• Waste Fuels
• Fits most furnaces

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Venturi Staged Burner Design
Staged air enters flame to complete burnout
Tertiary Air
Primary Air
Tertiary Air
Primary Air
Secondary Air
Fuel Rich Zone
Swirler imparts spin to primary air and creates a
stable recirculation zone
Simple Design / No Moving Parts
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Performance Characteristics

• Emissions
• NOx with FGR or Steam as low as 20ppm
• NOx with FGR and Steam as low as 16ppm.
• Typically CO is 0 at capacity but will range up
  to 50ppm
• Capacity Range
• 30 MMBTU/hr up to 400 MMBTU/hr

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Coen DAF

• Excellent Fuel Flexibility
• Flame Shaping Capabilities
• Custom Combustion Solutions

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DAF Burner Overview

• Mature Low NOx Technology
• Mature Product
• FGR for 30 ppm NOx
• ULN Design for 15 ppm NOx
• Excellent Fuel Flexibility
• Liquid Fuels
• Waste Fuels
• Variable Fuels
• Simultaneous Firing
• Battleship for Special Applications

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Product Development Initiatives

• Refinery Fuels NOx Reduction
• Bitumen / Heavy Oil Firing
• Emulsion Fuel Firing
• Multi-Fuel OTSG

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Largest Full-Scale Product Testing Facility
Tulsa, OK
Supporting Product Development Testing
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Computational Fluid Dynamics Lab
Flame Geometry
State of the art CFD workstations
Furnace Heat Transfer
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COOLflowTM
Physical Flow Modeling

• Evens airflow distribution
• Improves air and FGR mixing
• Reduces vibration
• Increases capacity
• Lowers emissions
• Lowers the excess air required
• Increases efficiency

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• World Leader In Advanced Clean-Air Solutions And
  Low-EmissionsCombustion Technologies.