CO and SCR System Evaluation Tools

For

2014 Plant Managers’ ConferenceSeptember 23, 2014

Bellevue, WA

Uncovering Value, Instilling Confidence

POWER PLANT SOLUTIONS

OUTLINE

Uncovering Value, Instilling Confidence

SCR System Basics

Catalyst

Flow Modeling

AIG Tuning

SCR Inspections

4NO + 4NH3 + O2 4N2 + 6H2O

Catalyst

2NO + NO2 + 2NH3 3N2 + 6H2O

SCR SYSTEM BASICS

Selective Catalytic Reduction (SCR) is the process of removing NOx (NO and NO2) out of the flue gas stream by injecting ammonia (NH3) into the flue gas as a reagent.

The flue gas passes over a fixed bed of catalyst installed in a reactor.

Ammonia reacts with nitrous oxides on the catalyst surface to form safe and clean nitrogen and water.

SIMPLE CYCLE SCR DESIGN - TYPICAL

Tempering Air

CO CATALYST – COMBINED & SIMPLE CYCLE

Designed to reduce CO from engine

Simple reaction (no reagent required):

O2 + 2CO 2CO2

Made from stainless steel substrate with precious metals added (platinum)

>90% Reduction typical

Deactivation over time can dramatically reduce performance

CO CATALYST SAMPLING

Should be tested when performance problems develop

Annual testing can identify problems before problems develop

CO CATALYST DEACTIVATION

The effect of catalyst aging results in degradation of performance

There are fewer active site and, typically, lightoff temperatures will increase, with a slower ramp-up.

Maximum conversions will also be lower.

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 100 200 300 400 500 600 700 800 900

% C

O O

xida

tion

Temperature, °F

CO Oxidation vs. Temperature (Lightoff Curves)

NEW AGED

SCR CATALYST – COMBINED & SIMPLE CYCLE

Designed to reduce NOx from engine

>90% Reduction typical

Ammonia Required

Deactivation over time can dramatically reduce performance

SCR CATALYST SAMPLING Should be tested when performance problems

develop

Annual testing will assure that goals are being met or when replacement is required

0.4

0.6

0.8

1

1.2

1.4

0 10000 20000 30000 40000 50000

Operating Time (h)

K/K

o (-

)

Unit-1 Unit-2 Initial Required Design

SCR CATALYST MANAGEMENT

“Cost effective planning for end of catalyst life”

Testing is a significant aid to optimal catalyst management

Sample testing

Performance testing

Operations

Options:

1. Replace catalyst with new

2. Rejuvinate used catalyst

3. Regenerate used catalyst

FLUID FLOW DESIGN CONSIDERATIONS

Poor flow distribution can have huge effect on system performance

Physical or CFD modeling is an effective economical means to identify AND fix flow problems

Poor flow, ammonia and temperature distribution can affect:

1. CO performance

2. SCR performance

1. NOx reduction

2. Ammonia Slip

3. Ammonia Usage

AIG TUNING

AIG should be designed with ability to tune as much as possible

Systems designed with no tuning capability have very limited flexibility

Adjustments to AIG can have significant benefit to performance

AIG DESIGN – THE NEED FOR GOOD AMMONIA DISTRIBUTION

High Aspect Ratio More Vertical Zones

Poor NH3/NOx distribution can significantly impact NH3 slip

As shown, the better (lower %RMS) the NH3/NOx distribution, the lower the overall ammonia slip (and ammonia usage)

AIG TUNING

Tuning performed by measuring NOx and O2 at the inlet and outlet of SCR catalyst

Can be done by manual traverse, but a permanent grid will provide much easier long-term testing and tuning

SCR INSPECTIONS – COMBINED & SIMPLE CYCLE

Inspections are a great method for identifying problems before performance issues develop Take catalyst samples (CO and SCR)

Check for Leaks - Gas Bypass is major contributor to performance problems

Seals between modules and along perimeter of reactor should be checked

Configuration Ammonia Slip,ppmvd @ 15% O2

Original Sealing System 6.8

With ENERActive Modified Sealing/Reinforcement System

2.0

SCR INSPECTIONS – COMBINED & SIMPLE CYCLE

Insulation Buildup can result in significant drop in performance

Pressure Drop

NOx and CO Reduction

Ammonia Slip

Source should be determined and corrected

ENERACTIVE OVERVIEW

Northeast Base with National Reach Asbury Park, New Jersey Clinton, New Jersey New York, New York Beltsville, Maryland (Washington DC)

Team Comprised of Field Engineers, Performance Engineers, Energy Engineers, Project/Construction Managers, and SMEs

Independent Technical Advisor for Component, System, and Plant Solutions

Projects Ranging From Simple Analyses to Multi-Million Dollar Implementation Efforts

#24 on Forbes List of Most Promising Companies

On NJBIZ’s List of 50 Fastest Growing Companies

POWER PLANT SOLUTIONS Services Include:

Complete Turnkey Projects

System Inspections Performance Testing Flow Modeling Performance Engineering AIG Tuning Catalyst Testing (CO and

SCR) Coal-Fired SCR

Optimization Combined Cycle/Simple

Cycle SCR System Optimization

CO Catalyst Systems for RICE

System Commissioning Control System Upgrades Specification

Development Feasibility Studies SCR Maintenance &

Catalyst Cleaning Catalyst Management

Energy Solutions… Efficient Results