Reinhold Environmental Ltd.2008 NOx-Combustion Round Table & Expo Presentation

February 4-5, 2008 in Richmond, VA

1212Airflow Sciences Corporation

Case Study Case Study –– IPL Harding Street Unit 7IPL Harding Street Unit 7

1313Airflow Sciences Corporation

Case Study Case Study –– IPL Harding Street Unit 7IPL Harding Street Unit 7

Low Load• CFD model: ΔT at catalyst ±20 °F• Physical model: ΔT at catalyst ±29 °F

Mid Load• CFD model: ΔT at catalyst ±22 °F• Physical model: ΔT at catalyst ±9 °F

Operating experience since start up May 2005• No problems achieving low load turndown• NOx reduction guarantees met

Low LoadLow Load•• CFD model: CFD model: ΔΔT at catalyst T at catalyst ±±20 20 °°FF•• Physical model: Physical model: ΔΔT at catalyst T at catalyst ±±29 29 °°FF

Mid LoadMid Load•• CFD model: CFD model: ΔΔT at catalyst T at catalyst ±±22 22 °°FF•• Physical model: Physical model: ΔΔT at catalyst T at catalyst ±±9 9 °°FF

Operating experience since start up May 2005Operating experience since start up May 2005•• No problems achieving low load turndownNo problems achieving low load turndown•• NOx NOx reduction guarantees metreduction guarantees met

1414Airflow Sciences Corporation

SCR Ammonia InjectionSCR Ammonia Injection

Tracer gas in physical model

Species tracking in CFD

Tracer gas in physical Tracer gas in physical modelmodel

Species tracking in CFDSpecies tracking in CFD

1515Airflow Sciences Corporation

Ash DepositionAsh Deposition

Duct floors

Turning vanes

Catalyst

Duct floorsDuct floors

Turning vanesTurning vanes

CatalystCatalyst

1616Airflow Sciences Corporation

Ash Deposition Ash Deposition –– Model TestingModel Testing

Drop out

Re-entrainmentDrop outDrop out

ReRe--entrainmententrainment

1717Airflow Sciences Corporation

SCR Large Particle Ash CaptureSCR Large Particle Ash Capture

Catalyst openings for coal-fired plants are smaller than LPA particles

Once LPA becomes “wedged” into a cell, fine ash builds up as well• Hard to clean• Get dunes of ash on top

layer catalyst

Catalyst openings for coalCatalyst openings for coal--fired fired plants are smaller than LPA particlesplants are smaller than LPA particles

Once LPA becomes Once LPA becomes ““wedgedwedged”” into a into a cell, fine ash builds up as wellcell, fine ash builds up as well•• Hard to cleanHard to clean•• Get dunes of ash on top Get dunes of ash on top

layer catalystlayer catalyst

1818Airflow Sciences Corporation

LPA ModelingLPA ModelingTrack ash particles through the ductwork and hopper regions

Calculate hopper capture efficiency for various particle sizes

Use model to evaluate wide range of design options

Track ash particles through the Track ash particles through the ductwork and hopper regionsductwork and hopper regions

Calculate hopper capture Calculate hopper capture efficiency for various particle efficiency for various particle sizessizes

Use model to evaluate wide Use model to evaluate wide range of design optionsrange of design options

5 mm particle streamlines -60% capture

Baseline Geometry

To SCR

Faerodynamic

m aFgravitational

Fbody

Forces on an ash particle