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POWER CATALOG

Tab Document Name Part Number

1 TABLE OF CONTENTS.................................................................................................... N/A

2 COMBUSTION AIRFLOW APPLICATIONSMeasuring Combustion Airflow & Pulverized Coal Flow ..................................................ICA-11Measuring Primary Airflow...............................................................................................ICA-01Measuring Bulk Secondary Airflow..................................................................................ICA-02

Measuring Bulk Secondary Airflow..................................................................................ICA-03Measuring Individual Burner Airflow ................................................................................ICA-06Pf-FLO with Mill Inlet Diverter..........................................................................................ICA-09Measuring Individual Burner Airflow ................................................................................ICA-10

3 COMBUSTION AIRFLOW MEASURING SYSTEMSVOLU-probe/SS Stainless Steel Pitot Airflow Traverse Probe .......................................125-068Combustion Airflow (CA) Measurement Station .............................................................125-495CAMS Combustion Airflow Management System ..........................................................125-009VELTRON DPT-plus Microprocessor Based Transmitter ...............................................125-025

4 PULVERIZED COAL FLOW MEASURING SYSTEMSPf-FLO III

TMPulverized Coal Flow Measurement ...........................................................125-196

Progress Energy Sutton 3 NOxReduction through Combustion Optimization ................ N/APf-FLO

TMReference Test at the Martin-Luther University Halle-Wittenberg...................... N/A

5 INDIVIDUAL BURNER AIRFLOW MEASURING SYSTEMSIndividual Burner Airflow Measurement ..........................................................................125-510

Accurate Burner Airflow Measurement for Low NOxBurners D.B. Riley ........................ N/A

6 CONTINUOUS EMISSIONS MONITORING SYSTEMS

CEM Systems Continuous Emissions Monitoring........................................................125-491

Proven solutions for a tough industry

1050 Hopper Avenue www.airmonitor.com [email protected] 707.544.2706 - PSanta Rosa, CA 95403 707.526.9970 - F

AIR MONITORPOW E R D I VI S I ON


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ICA-11

MEASURING COMBUSTION AIRFLOW

& PULVERIZED COAL FLOW

While the importance placed on combustion optimization for the purposes of reducing emissions and

improving efficiency varies by power plant, there are common applications at every power plant that would

greatly benefit from improved airflow measurement or the addition of pulverized coal flow measurement. AirMonitor Power is both pioneer and leader in the development of systems to accurately and reliably measure

combustion air and coal flow, with thousands of installations at virtually every utility in the United States. The

accompanying application bulletins outline the methods and benefits of measuring air and coal flow at the

locations indicated in the boiler overview below.

When applied by themselves or in combination, the addition of air and coal flow measurements will directly

contribute to:

REDUCINGCO, LOI & NOX

REDUCINGWATER WALL CORROSION

IMPROVINGMILL & BURNER PERFORMANCE

ELIMINATINGCOAL LAYOUT, MILL PLUGGAGE, PIPE FIRES & SLAGGING

LOWERINGSCR OPERATING COSTS &ACHIEVINGDESIRED BURNER STOICHIOMETRY

CEM

SAPA

Pf-FLO

IBAM

OFA




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APPLICATION BULLETIN

P.O. Box 6358 Santa Rosa, CA 95406 707-544-2706 - P 707-526-9970 - F www.airmonitor.com

ICA-01

4/09, Rev.1

Ductwork providing primary air to a

pulverizer typically has limited straight

runs, control dampers, and a

convergence point of hot and

tempering air, all of which make the

selection and placement of the airflow

measurement device(s) critical to the

success of the installation. The

following three examples show the

use of Fechheimer-Pitot Combustion

Air (CA) stations and/or VOLU-probe/SS arrays, and their optimum

locations.

In applications with at least 1

diameters of straight duct run between

the hot air/tempering air mixing point

and the elbow upstream of the

pulverizer control damper, a CA station

is used to measure total primary air.

See Figure 1.

while insufficient primary air results in

slagging, coal layout, pipe fires,

eyebrows, and burner pluggage.

Usable measurement of primary air

cannot be obtained from existing devices

such as venturis, foils, jamb tubes, etc.,

or instrumentation such as thermal

anemometers due to limited available

straight duct runs, low flow rates, broad

turndown range and high concentrationsof airborne particulate (flyash). The need

is airflow instrumentation capable of

overcoming these challenging operating

conditions, to optimize both mill operation

and burner performance.

MEASURING PRIMARY AIRFLOW

The objectives in the power industry

today are twofold; to lower emissions,

and increase plant performance.

Precise measurement of combustion

airflow and fuel rates positively

contributes to achieving those

objectives by providing the information

needed to optimize stoichiometric

ratios and facilitate more complete,

stable combustion.

The main functions of primary air are

to dry the coal and then pneumatically

convey the pulverized coal from the

mill to the individual burners. Primary

air also determines coal particle

velocity at the burner exit, in part

defining the flame position relative to

the burner tip and impacting flame

stability, both key factors in achieving

optimized burner performance.

Excessive primary air contributes to

high NOxformation and tube erosion,

The Challenge The Solution

Figure 1

CA Station w/Temperature Probe and Transmitter

CAMS Purge and Transmitter

Opposed Blade Damper

T.P. and S.P. Signal Tubing

4-20mADC from Temperature Sensor

4-20mADC Flow Signal to DCS (lbs/hr)

100 psi Plant Air

A

E

F

G

H

I

K


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ash. The purge cycle can be

configured to operate on a

programmable interval or initiated via

a dry contact from the DCS. During

the purge cycle the CAMM maintains

a locked signal output to the DCS

while providing a dry contact

notification of purge cycle start andfinish.

These systems provide airflow

measurement accurate to within 3%

of actual airflow over a 10:1 turndown

range. The signals remain stable with

zero drift, and due to AUTO-purge the

flow elements can operate

continuously within the heavy

particulate environment. To date

thousands of these systems have

been installed within fossil fuel powerplants to help reduce NO

xand CO,

improve flame stability, avoid coal pipe

layout, minimize LOI/UBC, increase

combustion efficiency, and reduce

waterwall corrosion.

Coal mass flow and particle velocity

data from a Pf-FLO coal flow

measurement system allow further

optimization of primary air by providing

the means of customizing a mills PA

to Feeder curve to meet the unique

operating conditions of each powerplant; curves that are dependent upon

variable coal type, moisture content,

coal pipe arrangement, and actual

fuel distribution.

the CAMS enclosure the pressure signals

plus airflow temperature are converted

by the CAMM into a density compensated

lbs/hr mass flow output to the DCS.

When two flow elements are supported

by a single CAMS, both the individual

and summed mass flow outputs are

made available to the DCS.

The CAMM also manages the AUTO-

purgeTMsystem used to keep the airflow

station or probe array sensing ports and

signal lines clear of accumulating fly

Where insufficient straight duct run

exists downstream of the air mixing

point, or separate measurement of

hot and tempering air is desired to

control mill outlet temperature, CA

stations or VOLU-probe/SS arrays

can be installed in both air ducts

upstream of the control dampers, oneduct diameter for the CA Station and

two diameters for the VOLU-probe/

SS array. See Figure 2.

On exhauster mills the tempering air

is often not ducted but instead enters

via a barometric opening on the side

of the ductwork. For this application

an integrated bell mouth CA station

with extended casing is utilized to

create the necessary minimum run of

straight ductwork needed to

accurately measure the tempering

airflow. A control damper can also be

added. See Figure 3.

The total and static pressure signals

from one or both CA Stations or VOLU-

probe/SS arrays are routed to the

Combustion Airflow Management

System (CAMS) enclosure. Within

The Solution(con't)

Result

Figure 2

Figure 3

CA Station

CA Station w/Bellmouth

VOLU-probe/SS Array

Thermocouple Probe w/TemperatureTransmitter


Opposed Blade Damper

T.P. and S.P. Signal Tubing4-20mADC from Temperature Sensor


100 psi Plant Air

A

B

C

D

E

F

G

H

J

K


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ICA-02

4/09, Rev.1

need for five to eight straight lengthsof duct runs at the point of installationto obtain true accuracy andrepeatability, 4) Cannot achieve alinear mass flow output over a broadoperating range with a single K-factor.

fuel ratio at varying load conditions.Although airfoils and venturis haveprovided adequate airflow measurementin the past, achieving current emissionreduction mandates and performanceobjectives require a more accurate andcost effective means of airflowmeasurement.

Venturis and airfoils have known

limitations: 1) Significant non-recoverable pressure loss that wastespower and can limit generated output; 2)Decreased accuracy and noisy signalsat high turndown operating conditionsassociated with low NO

xretrofits; 3) The

MEASURING BULK SECONDARY AIRFLOW

The objectives in the power industrytoday are twofold; to lower emissions,and increase plant performance.Precise measurement of combustionairflow and fuel rates positivelycontributes to achieving thoseobjectives by providing the informationneeded to optimize stoichiometricratios and facilitate more complete,stable combustion.

Traditional coal fired power plantdesign utilized airfoils or venturis formeasurement of bulk primary andsecondary airflow for the purpose ofmaintaining the correct boiler air to

The Challenge

The Solution

A Florida utility was engineering a low

NOx burner retrofit on their 300MWgas/oil wall fired boiler. In order to gainneeded fan capacity and obtain a moreaccurate measurement of airflow overa higher range of turndown, Air MonitorPowers Application EngineeringDepartment suggested the total airventuri be removed and replaced witha VOLU-probe/SS array. See Figure1.

Figure 1


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System (CAMS) enclosure. Within theCAMS enclosure the pressure signalsplus airflow temperature are convertedby the CAMM into a density compensatedlbs/hr mass flow output to the DCS. Thetwo mass flow inputs, one from eachCAMM, were summed in the DCS to

arrive at a total bulk airflow.See Figure 2.

The CAMM also manages the AUTO-purgeTMsystem used to keep the VOLU-probe/SS sensing ports and signal linesclear of accumulating fly ash. The purgecycle can be configured to operate on aprogrammable interval or initiated via adry contact from the DCS. During thepurge cycle the CAMM maintains alocked signal output to the DCS whileproviding a dry contact notification ofpurge cycle start and finish.

The measuring location was a 40long section of duct downstream oftwin forced draft (FD) fans and arotary air pre-heater. The two fans

joined into a common 5 x 75 ductupstream of the pre-heater, and itwas believed that the flow rates on

either side of the duct would varydepending on the load changes oneither fan.

Two side-by-side measurementarrays, each having sevenFechheimer-Pitot VOLU-probe/SSmeasuring 60" in length, wereinstalled. For each array the VOLU-probe/SS total and static pressuresignal connections were manifoldedtogether and routed to their ownCombustion Airflow Management

ResultThe Solution

The removal of the venturi providedthe needed additional fan capacity,while saving an estimated $10,000 inreduced power consumed by eachFD fan. The installed VOLU-probe/SS arrays achieved the desired 3%measurement accuracy over the full

4:1 range of turndown. Due to theCAMS sensitivity to small changes inairflow, a cyclic drop in airflow wasdetected and traced back to one ofthe pre-heaters twelve sections beingplugged.

Subsequent to the initial installation,Air Monitor Power assisted thecustomer in reconfiguring themanifolding of the two VOLU-probe/SS arrays as in Figure 3. The revisedarrangement resulted in two fully

redundant systems, each measuringthe total bulk airflow without anysumming in the DCS. When onesystem was performing a purge cycle,the other system continued to providedynamic flow measurement.

VOLU-probe/SS Array

Thermocouple Probe w/Temperature Transmitter

T.P. and S.P. Signal Tubing


100 psi Plant Air


4-20mADC from Temperature Sensor

A

B

C

D

E

F

G

Figure 2 Figure 3


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ICA-03

4/09, Rev.1

Venturis and airfoils have knownlimitations: 1) Significant non-recoverable pressure loss that wastespower and can limit generated output;2) Decreased accuracy and noisysignals at high turndown operatingconditions associated with low NO

x

retrofits; 3) The need for five to eightstraight lengths of duct run at the pointof installation to obtain true accuracy

and repeatability, 4) Cannot achieve alinear mass flow output over a broadoperating range with a single K-factor.

Traditional coal fired power plant designutilized airfoils or venturis formeasurement of bulk primary andsecondary airflows for the purpose ofmaintaining the correct boiler air to fuelratio at varying load conditions. Althoughairfoils and venturis have providedadequate airflow measurement in thepast, achieving current emissionreduction mandates and performance

objectives require a more accurate andcost effective means of airflowmeasurement.

MEASURING BULK SECONDARY AIRFLOW

The objectives in the power industrytoday are twofold; to lower emissions,and increase plant performance.Precise measurement of combustionairflow and fuel rates positivelycontributes to achieving thoseobjectives by providing the informationneeded to optimize stoichiometricratios and facilitate more complete,stable combustion.

The Challenge


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notification of purge cycle start and finish.FD fan operating costs were reducednearly $50,000 per year, resulting in a21-month payback for the project. As aresult of the installed VOLU-probe/SSarrays measurement accuracy wasgreatly improved, to within 3% of actual

airflow over the 4:1 range of turndown.

Air Monitor Power s App licationEngineering Department was calledupon by a Georgia utility to designand provide airflow measuringsystems to replace three airfoils andone air dam within their 500MW, coalfueled, T-fired boiler. The project

objective was to gain needed FDcapacity, with the cost justificationexpected to come from a reduction inenergy required to operate the FDfans.

Airfoils in three locations and an airdam were removed one airfoil ineach of the 12 x 15 bulk secondaryair ducts, one airfoil in the 6 x 6 hotprimary air duct serving the mills, andthe air dam in the 5x 5 tempering airduct. Fan curve data indicated the

total non-recoverable pressure losscaused by the airfoils and air damwas slightly more than 3" w.c., wastingnearly 300 HP per fan.

An array of Fechheimer-Pitot VOLU-probe/SS were installed in each of thefour measurement locations: Tenprobes 12 in length in each of the twosecondary air duct, five probes 6' inlength within the hot PA duct, andfour probes 5' in length in thetempering air duct. For each array

the VOLU-probe/SS total and staticpressure signal connections weremanifolded together and routed totheir own Combustion AirflowManagement System (CAMS)enclosure. Within the CAMSenclosure the pressure signals plusairflow temperature are converted bythe CAMM into a densitycompensated lbs/hr mass flow outputto the DCS.

The CAMM also manages the AUTO-purgeTM system used to keep theVOLU-probe/SS sensing ports andsignal lines clear of accumulating flyash. The purge cycle can beconfigured to operate on aprogrammable interval or initiated viaa dry contact from the DCS. Duringthe purge cycle the CAMM maintainsa locked signal output to the DCSwhile providing a dry contact

ResultThe Solution


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ICA-06

4/09, Rev.1

angles blades in each barrel, a

combination of fixed and/or adjustable

inlet sleeve/disk dampers, and in most

installations the burners were equipped

with actuators to facilitate DCS controlled

modulation of burner SA airflow

corresponding to varying fuel loads.

Unfortunately some low NOx burners

come equipped with a non-calibrated

airflow sensing device and most others

lack any means to determine how muchSA is entering the burner, resulting in the

need for extensive burner tuning targeted

at meeting the manufacturers NOxand

CO emissions guarantees but not

repeatable or maintainable long term

over varying load conditions.

Just as there are variances in fuel

distribution to each burner, multiple

MEASURING INDIVIDUAL BURNER AIRFLOW










stable combustion.

Traditional coal fired power plant

designs lacked any means to measure

and control airflow into individual

burners. New burner designs

prompted by Clean Air Act attainment

levels for NOxreduction are typically

comprised of inner and outer airflow

barrels to introduce secondary air (SA)

to the flame ball, adjustable swirl

The Challenge

burners served by a common or

partitioned wind box can have

substantial burner-to-burner im-

balances in SA Accurate and

repeatable measurement of individual

burner SA requires airflow probes that

are economically feasible to retrofit

into existing burners and yet able to

accommodate a variety of design

challenges the absence of any

undisturbed cross section of airflowpassage; an installation location

typically downstream of a modulating

inlet sleeve or disk damper; a broad

range of boiler operating conditions;

the presence of fly ash particulate; and

the broad range of airflow pitch and

yaw vectors produced by the adjustable

swirl angle blades.


10/108

Customized IBAMs characterized in

the Air Monitor Power wind tunnel and

used in conjunction with a CAMS result

in individual burner SA measurement

accurate to within 5% of actual airflow

over the full range of boiler operation.

Statically balanced burner-to-burnerairflow is a critical first step in optimizing

boiler performance while simul-

taneously reducing undesirable

emissions. In several installations, just

balancing the airflow was sufficient to

achieve lower NOxemissions levels.

Further reductions in NOxlevels are

obtained when continuous burner SA

measurement is combined with DCS

controlled modulation of airflow control

to dynamically maintain burner-to-

burner airflow balance or a burnerbias strategy corresponding to the

varying fuel loads.

Incorporating Pf-FLO coal flow

measurement for EACH burner

permits adjusting SA to reflect the

actual fuel being delivered to each

burner, thereby achieving the desired

fuel / air ratio, safely lowering overall

NOx while simultaneously reducing

areas of high CO that otherwise

produce undesirable slagging and

water wall corrosion.

Over-fire Airflow (OFA) measurement

is another common NOx reduction

technique that alone, or in conjunction

with SA measurement and control,

requires the accurate measurement

capabilities of the IBAM to ensure the

proper amount of OFA is used to

obtain the best possible NOxsolution

via staged combustion, while

simultaneously minimizing CO and

LOI.

The IBAM signals are routed out of the

wind box to the Combustion Airflow

Management System (CAMS)

enclosure. Within the CAMS enclosure

the pressure signals plus airflow

temperature are converted by the CAMM

using the polynomial equation, into a

density compensated lbs/hr mass flowoutput to the DCS.

The CAMM also manages the AUTO-

purgeTM system used to keep the IBAM

sensing ports and signal lines clear of

accumulating fly ash. The purge cycle

can be configured to operate on a

programmable interval or initiated via a

dry contact from the DCS. During the

purge cycle the CAMM maintains a

locked signal output to the DCS while

providing a dry contact notification of

purge cycle start and finish.

Air Monitor Powers Individual Burner

Airflow Measurement (IBAM) probes,

a modified version of the VOLU-probe/

SS, are designed burner specific to

accurately measure burner SA.

Based upon the Fechheimer-Pitot

measurement technology, each IBAM

design draws from a broad array ofconstruction options: Quantity and

location of individual TP and SP

sensing holes; CW and/or CCW

rotation of the individual TP and SP

sensing probes; rotation of the entire

IBAM assembly; and the use of ultra

high temperature alloys and Tungsten

Carbide coatings. The configuration

of inner and outer airflow barrels,

along with the locations of the burner

registers and obstructions such as an

igniter, typically define the possible

IBAM mounting locations. Wind boxconfiguration and burner symmetry

guide the quantity of IBAMs needed

to obtain desired accuracy and

repeatability.

Each IBAM probe is extensively tested

and characterized in Air Monitor

Powers large scale test duct, installed

either in a full size burner mock-up or

the actual burner. Testing is

conducted over a broad matrix of

customer specific sleeve damper or

inlet disk positions, swirl anglesettings, and boiler operating

conditions. The result is a multi-order

polynomial equation, with one or two

variables, to accurately correlate the

total and static pressure signals from

the IBAMs into mass flow.

ResultThe Solution


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12/108

Air Monitor Power assisted the Utilitys

contractor in the development of new

control logic using the coal mass flow

measurements from each of the four

pipes served by a single mill; by

summing the two coal flow

measurements corresponding to each

mill end a control output was generatedto reposition the diverter damper,

automatically maintaining end-to-end

mill balance within 5%. Data from

the Pf-FLO system was also used to

guide the process of statically adjusting

each primary riffle box to balance the

fuel being delivered to both burners.

The combined effect of manual riffle

adjustment and implementation of

automatic diverter damper control was

successful in achieving the primary

objective of 10% coal delivery

balance to all burners over the normalrange of boiler operation.

In conjunction with the coal diverter a Pf-

FLO Coal Flow Measurement System

was installed on all 20 pipes, initially to

gather baseline coal distribution data

over the Units full range of load

conditions. By summing the mass flow

of pipes 1 & 2 served by the mills left end

and comparing it to the summed massflow of pipes 3 & 4 served by the mills

right end, the baseline data collected in

Pf-VU confirmed the existence of 20%

end-to-end imbalance at different load

conditions, and as much as 35% fuel

variance between the lightest and

heaviest loaded pipes. By means of

manually biasing the diverter blade

position the ability to achieve mill end-to-

end balance was demonstrated.

To address the end-to-end fuel

imbalance Air Monitor Powers

Application Engineering department

engineered a coal diverter with

actuator that was installed into the top

section of the existing coal / PA duct.

Diverter components directly exposed

to coal were constructed of wearresistant alloys, with an overall design

that permitted ease of periodic

inspection for long term removal and

replacement. The diverter was

engineered to permit as much as

25% end-to end bias via a control

signal from the DCS. A divider plate

was also installed to maintain the coal

distribution from the diverter into the

mill entrance. See Figure 1.

ResultThe Solution

Figure 2


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ICA-10

4/09, Rev.0

adjustment of the secondary airflow is to

be applied to each burner compartment.

Ai r Monito r Power s Appl ica ti on

Engineering department was called upon

by a Southeast utility to design a system

to measure airflow entering the individual

fuel and aux air compartments of their

tangentially fired 350MW plant, wherenew low NO

xburners were being installed

as part of a total boiler upgrade.

The design solution was based upon the

fact that airflow passing through a fixed

resistance element (louver, perforated

plate, orifice plate, etc.) produces a

measurable, repeatable pressure drop,

such that the airflow can be

mathematically expressed in the form of

a power curve or polynomial equation

using pressure drop as the variable. In

MEASURING INDIVIDUAL BURNER AIRFLOW










stable combustion.

Traditional designs of tangentially

fired, coal power plants lack any

means to measure secondary airflow

entering each fuel and aux air

compartment. Efforts to meet NOxattainment levels mandated by the

Clean Air Act were frequently achieved

by means of extensive and often non-

repeatable tuning of burner settings

solely targeted at meeting the NOxand CO emissions guarantees at a

single load condition. Just as there

are variances in fuel distribution toeach burner, multiple burners served

by a common wind box ended up with

substantial burner-to-burner imbal-

ances in secondary airflow (SA).

On tangentially fired boilers the

modulating control damper at the

entrance to each secondary air inlet

has little if any straight duct run, not

providing a location where even just a

repeatable signal representative of

actual airflow can be obtained. Since

the secondary air inlets are not easily

accessed for maintenance or repair,

any airflow measuring instrumentation

must be durable and repeatable,

providing stable, accurate input

signals to the DCS if a combustion

optimization strategy using continuous

The Challenge

this tangentially fired application the

dampers are modulated to control

airflow, thereby making them variable

resistance elements whose

relationship to airflow becomes a

mathematical function of two variables

the measured pressure drop across

the damper and the damper position.

Each corner consisted of four burner

elevations with three blade controldampers, five aux air compartments

with two blade dampers, plus a top air

and a bottom air compartment each

with a single damper blade. A full scale

mock-up of the wind box corner was

constructed, complete with physical

replications of the three different

damper configurations, equipped with

The Solution


14/108

An engineered solution consisting of

customized SAP sensors, detailed

damper characterizations and CAMS

resulted in individual compartment SA

measurement accurate to within 5%

of actual airflow over the full range of

boiler operation.

The ability to accurately balance and/

or bias individual corner airflow was a

critical first step in optimizing boiler

performance while simultaneously

reducing undesirable emissions.

Further reductions in NOxlevels were

obtained when the continuous corner

SA measurements were combined

with nozzle tilt adjustments and DCS

controlled modulation of the control

dampers to dynamically maintain a

burner and aux air strategy at varying

fuel loads.

In addition to its essential contribution

to optimization of PA / Feeder curves,

incorporating Pf-FLO coal flow

measurement for EACH burner

allowed automatic adjustment of SA

to reflect the actual fuel being delivered

to each burner, thereby achieving the

desired fuel / air ratio for each burner

while safely lowering overall NOxand

reducing areas of high CO that

otherwise produce undesirable

slagging and water wall corrosion.

ruggedized version of Air Monitors SAP

(Static Air Probe) was engineering to

meet the application requirements.

The static pressure signals from the

upstream and downstream SAPs were

routed out of the wind box to the

Combustion Airflow ManagementSystem (CAMS) enclosure. Within the

CAMS enclosure the pressure signals,

airflow temperature, and damper position

input are converted by a CAMM/TFA

using the multi-order damper

characterization equations, into a fully

density compensated lbs/hr mass flow

output to the DCS.

The CAMM/TFA also manages the

AUTO-purgeTMsystem used to keep the

SAP sensing ports and signal lines clear

of accumulating fly ash. The purge cyclecan be configured to operate on a

programmable interval or initiated via a

dry contact from the DCS. During the

purge cycle the CAMM/TFA maintains a

locked signal output to the DCS while

providing a dry contact notification of

purge cycle start and finish.

the new actuators that were part of

the boiler upgrade, and attached to

Air Monitor Powers large scale test

duct. Based upon customer provided

current and future operating

parameters, a 286 point test matrix

consisting of three variables (windbox

static pressure, damper position,damper size) was developed for

characterizing each damper

individually, followed by verification

testing of multiple dampers being

modulated simultaneously. The result

was a developed series of multi-order

polynomial equations correlating the

pressure drop signal and damper

position into air mass flow.

A key component of the project was

designing the static pressure sensors

required to measure the pressure dropacross the control dampers. The

sensors had to operate in the

presence of fly ash particulate, be

economically feasible to retrofit into

the existing compartments, and not

be adversely impacted by changing

airflow patterns downstream of the

modulating dampers. A custom

ResultThe Solution(con't)


15/108



ICA-12

4/09, Rev.1

by ASME, ASHRAE, and in fluid

mechanics textbooks.

Air Monitor Powers line of application

proven Combustion Airflow

Management Modules (CAMM) with

ultra-low spans (as low as 0.05" w.c.

Full Span) and high accuracy (0.1% of

Full Span) allows the engineering of

venturis with an optimized high .8 beta

factor one that optimizes the flowprofiling benefits as air is compressed

passing through the throat of the

venturi, against the unrecovered

pressure drop of the venturi itself. The

resultant Venturi/HBTM (High Beta)

maximizes the amount of primary air

available to the mill while providing

accurate airflow measurement over a

wide range of operation.

Venturis have long been used in power

generation to measure airflow because

of their ability to create a differential

pressure signal that could be field

characterized to represent lbs/hr of air.

Historically venturis with a .5 beta factor

(the ratio of venturi minimum cross

section to the full size upstream duct

cross section) were engineered to

produce the 20-30 inches of differential

pressure required by the differentialpressure transmitters of that era, but did

so at the expense of a high unrecovered

pressure drop, waste of energy and

imposed limit on available air for com-

bustion. The measurement performance

of traditional venturis was further

compromised by field calibration

methods relying on the use of the S-type

Pitot in duct locations far short of the

minimum requirements recommended

MEASURING PRIMARY AIRFLOW










stable combustion.

The main functions of primary air are

to dry the coal and then pneumatically

convey the pulverized coal from the

mill to the individual burners. Primary

air also determines coal particle

velocity at the burner exit, in part

defining the flame position relative to

the burner tip and impacting flame

stability, both key factors in achieving

optimized burner performance.

Excessive primary air contributes to

high NOxformation and tube erosion,

while insufficient primary air results inslagging, coal layout, pipe fires,

eyebrows, and burner pluggage.

Short duct sections are commonplace

in coal fired power plants and Air

Monitor Power, with its Fechheimer-

Pitot Combustion Air (CA) stations

and/or VOLU-probe/SS arrays, has

demon-strated the ability to accurately

measure combustion airflow without

the need for field calibration. But

primary airflow typically combines hot

and tempering air supplies with control

dampers and limited straight duct

sections, resulting in ductwork

configurations that produce highly

distorted velocity profiles, often with

airflow angularity beyond the 30

degrees of pitch and/or yaw

measurement accuracy limitations of

a CA station or VOLU-probe/SS array.

The Challenge The Solution

VENTURI/HBTM

Shown with optionalVOLU-probe/SS


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Construction Features

Stainless Steel Airf low Traverse Probes

Features

Provides for Equal Area Traverse. Each VOLU-probe/SS

contains multiple total and static pressure sensors specifically and

precisely located along the length of the probe to provide an equal

area traverse of ducted airflow. For rectangular duct configurations,

the sensors are spaced at equal distances along the probe. For

circular duct configurations, the sensors are located at the centers

of the equivalent concentric area along the probe.

True Velocity Pressure Measurement. The total and static

pressure components of airflow measured by the VOLU-probe/SS

can be directly converted in velocity pressure (and velocity) without

the use of correction factors, thereby facilitating flow verification

with a Pitot tube or other hand held instrumentation.

No Sensor Protrusions. The VOLU-probe/SS total and static

pressure sensors are all contained within the confines of the external

surface of the probe. There are no protruding sensors to be bent,

broken, or otherwise damaged during installation or possible

subsequent removal for inspection or cleaning.

Rugged Construction Assures Long Service Life. The standard

VOLU-probe/SS is fabricated from Type 316 stainless steel using

all welded construction. See Page 4 for construction options, and

contact Factory for alternate materials of construction such as

Hastelloy, Inconel, Kynar, PVC, etc.

No Air Straighteners Required. The VOLU-probe/SS unique

dual offset static pressure sensor and patented chamfered total

pressure sensor design permit the accurate measurement of the

airflow rate in highly turbulent flow locations (with directional

yaw and pitch varying up to 30 from the duct's longitudinal axis)

without the need for upstream air straightening means.

Offered in Two Models. The VOLU-probe/SS is offered in two

basic configurations to facilitate installation in new or existing

ducts or stacks; the Model 1 for external mounting, and the Model

2 for internal mounting.

Negligible Resistance to Airflow. The VOLU-probe/SS

cylindrical configuration and smooth surface free of external sensor

protrusions permit the airstream to flow unrestricted around and

between the installed traverse probes, creating a very minimal, if

not negligible resistance to airflow (Ex: 0.046 IN w.c. at 2000 fpm

air velocity).

Performs Equal-Weighted Averaging of Flow Signals. Through

the use of separate averaging manifolds, the VOLU-probe/SS

instantaneously averages, on an equal-weighted basis, the multiple

pressures sensed along the length of the probe, producing separate

"averaged" total pressure and static pressures at the probe's external

signal connections.

FPT Signal Connections

Offset Fechheimer Static Pressure Sensors

Integral 10 Gauge Mounting Plate

Chamfered Total Pressure Sensors


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CA Station

How It Works

The CA Station is also ideally suited to measure SA entering

each burner level of a partitioned windbox, SA being taken

out of a windbox to supply multiple OFA ports, at the ducted

inlet of FD fans, and bulk SA entering each windbox of a

corner fired unit.

The Need for Combustion Airflow Measurement

The objectives in the power industry today are twofold; to

lower emissions, and increase plant performance. Precise

measurement of combustion airflow and fuel rates positively

contributes to achieving those objectives, by providing the

information needed to optimize stoichiometric ratios andfacil i tate more complete, stable combustion. Usable

measurements cannot be obtained from existing devices such

as venturis, foils, jamb tubes, etc., or instrumentation such

as thermal anemometers due to limited available straight duct

runs, low flow rates, proximity to modulating control dampers,

broad turndown range, and high concentrations of airborne

particulate (flyash).

Air Monitor Power s ruggedly constructed Combustion Air

(CA) Station, with both integral airflow processing cell and

Fechheimer-Pitot measurement technology, is engineered to

meet the challenging operating conditions of the typical power

plant while providing mass flow measurement of PA, SA, and

OFA within an accuracy of 2-3% of actual airflow.

While the main functions of primary air are to first dry and

then pneumatically convey the pulverized coal from the mill

to the individual burners, it also determines coal particle

velocity at the burner exit, influencing the flame position

relative to the burner tip and impacting flame stability, both

key factors in achieving optimized burner performance.

Accurate PA measurement obtained with a CA Station can

contribute to reducing NOxand CO, improving flame stability,

avoidance of coal pipe layout, minimizing LOI/UBC, reducing

waterwall corrosion, and increasing combustion efficiency.

Log-Tchebycheff Sensor Location. A high concentration

of total and static pressure sensors positioned according tothe log-Tchebycheff rule sense the multiple and varying flowcomponents that constitute the airstream's velocity profile.

The log-Tchebycheff's perimeter weighted sensor pattern is

utilized to minimize the positive error (measurements greaterthan actual) caused by the failure to account for slower

velocities at the duct wall when using traditional equal area

sensor locations. Spacing of total pressure sensors is perthe table below. Since the static pressure across the station

is relatively uniform, a lesser number of static pressure

sensors are utilized to minimize unrecovered pressure drop.

Fechheimer Pitot Flow Measurement. The CA Stationoperates on the Fechheimer-Pitot derivative of the multi-point,

self-averaging Pitot principle to measure the total and static

pressure components of airflow. Total pressure sensing portswith patented (U.S. Patent No. 4,559,835) chamfered

entrances, and Fechheimer pairs of offset static pressure

sensing ports combine to minimize the effect of directionalairflow. When located downstream of honeycomb airflow

processing cell, the Fechheimer Pitot method is extremely

effective at accurately measuring airflow in limited straightduct runs.

Ai rf lo w Processing. To assure extremely high levels of

measuring accuracy (3% of actual flow) under extremeconditions caused by turbulent, rotating, and multi-directional

airflows normally present near fan inlets, discharge ducts,and directly downstream from duct elbows, transitions, etc.,

the CA Station uses open, parallel cell, honeycomb panels to

"process" the air into straightened flow just prior to the totalpressure measurement plane. These honeycomb panels

sharply reduce the need for long, straight runs of duct before

and after the station to obtain accurate flow measurement.

Negl igible Air f low Resistance. The CA Station airfl ow

measuring station is designed to function while producing aminimum of resistance to air f low, due to the unique

honeycomb air straightener-equalizer section having a free

area of 96.6%. The unique, non-restrictive characteristic of

the CA Station is seen in the Resistance vs. Airflow Velocitygraph below. The values indicated are total resistance and

do not include any allowances for static regain (a potential20% reduction to the values).

Denotes CA Station location

Duct / Station

Configuration

Rectangular

Circular

Quantity of Sensing Points

25 or more points, maximum 6" or 8" apart,depending on duct size.

12 to 30 points, along 2 or 3 diameters.


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Construction Features

Combustion Airflow Measurement Station

Specifications

Minimum Installation Requirements

Welded 3/16"

Carbon Steel Casing

90 Connection Flanges

12" Depth

24 ga. Carbon Steel

Airf low Straightener

Offset Fechheimer Static

Pressure Sensing Probe

Total Pressure Sensing Manifold

Configurations.

Rectangular, Circular, and Custom

Accu racy.

2-3% of actual flow

Operating Temperatures.

Continuous operation to 800F

Connection Fittings .

1/2" FPT, Type 316 stainless steel

Static and Total Pressure Sensing Manifolds .

Type 316 stainless steel, welded construction

Air f lo w St ra ig htener.

1" hexagonal, parallel cell straightener, 3" deep,

24 ga. (.024") thick carbon steel

Casing and Flanges .

3/16" carbon steel, continuous welded seams

Casing depth is 12"

Special Construction Options.

Sensing Manifold Cleanouts

Inlet Bell Mouth

Multi-point Temperature Measurement

Alternate Materials of Construction

Integral Control Damper

Optional Manifold Cleanouts

DAMPERS

BRANCH DUCT

BELLMOUTH / FAN INLET

CONVERGINGDUCTS

REDUCING TRANSITION EXPANDING TRANSITION UNVANED ELBOW ELBOWVANED


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125-495 (04-09)

P.O. Box 6358 Santa Rosa, CA 95406 P: 800-AIRF LOW F: 707-526-9970www.airmonitor.com [email protected]

Air Monitor Power's Product Families of A ir & Coal Flow Measurement Systems

IBAMTM Individual Burner Airflow MeasurementThe IBAMTM Individual Burner Airflow Measurement probe is ideally suited for new or

retrofit applications where a reduction in plant emissions and improvement in efficiency

can be obtained through accurate measurement of burner secondary airflow. The IBAMTM

probe has been designed to accurately measure in the particulate laden, high operating

temperature conditions found in burner air passages.

CEMSTM Continuous Emissions Monitoring SystemAir Monitor Power's CEMSTM Continuous Emissions Monitoring Systems assist in

complying with the Clean Air Acts stringent emission measurement standards and the

requirements of 40 CFR 75. Air Monitor has assembled a cost effective integrated system

consisting of in-stack flow measurement equipment and companion instrumentation to

provide continuous, accurate, and reliable volumetric airflow monitoring of stacks and ducts

of any size and configuration.

CAMSTM Combustion Ai rf low Management Systems .The CAMSTM Combustion Airflow Management System has been designed to reliably

and accurately measure airflow in combustion airflow applications. The CAMSTMcontains

the microprocessor based instrumentation to measure the airflow and manage the AUTO-

purge. The AUTO-purge is a high pressure air blowback system that protects the duct

mounted flow measurement device from any degradation in performance due to the

presence of airborne particulate (flyash).

Engineering & Testing Services. Air Monitor Power offers complete engineering and testing to analyze air and coaldelivery systems. Air Monitor Powers field testing services use 3D airflow traversing and Pf-FLOcoal flow measurement

systems for the highest possible accuracy. To ensure cost effective and accurate solutions, Air Monitor Power has full scale

physical flow modeling capability and in house Computational Fluid Dynamics (CFD). CFD analysis is used to analyze flow

profiles and design/redesign ductwork to improve overall performance. Full scale model fabrication and certified wind tunnel

testing is used to develop application specific products that will measure accurately where no standard flow measurement can.

Pf-FLOTM Pulverized Fuel Flow ManagementThe Pf-FLOTM system performs continuous and accurate fuel flow measurement in

pulverized coal fired combustion applications, providing boiler operators with the real-time

data needed to balance coal mass distribution between burners. Balanced fuel improves

combustion efficiency and lowers emissions while reducing in-furnace slagging, coal layout,

fuel slagging, and coal pipe fires.

VOLU-probe/SSTMStainless Steel Air flow Traverse Probes.Multi-point, self-averaging, Pitot-Fechheimer airflow traverse probes with integral airflow

direction correcting design. Constructed of Type 316 stainless steel and available in

externally and internally mounted versions for harsh, corrosive or high temperature

applications such as fume hood, laboratory exhaust, pharmaceutical, and clean room

production and dirty industrial process applications.



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CAMSCombustion Airf low Management System



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125-009-00 (/)

P.O. Box 6358 Santa Rosa, CA 95406 P: 800-AIRFLOW F: 707-526-9970www.airmonitor.com [email protected]

Air Monitor Power's Product Families of A ir & Coal Flow Measurement Systems

IBAMTM Individual Burner Airflow MeasurementThe IBAMTM Individual Burner Airflow Measurement probe is ideally suited for new or


can be obtained through accurate measurement of burner secondary airflow. The IBAMTM

probe has been designed to accurately measure in the particulate laden, high operating

temperature conditions found in burner air passages.

CEMSTM Continuous Emissions Monitoring SystemAir Monitor Power's CEMSTM Continuous Emissions Monitoring Systems assist in

complying with the Clean Air Acts stringent emission measurement standards and the

requirements of 40 CFR 75. Air Monitor has assembled a cost effective integrated system

consisting of in-stack flow measurement equipment and companion instrumentation to

provide continuous, accurate, and reliable volumetric airflow monitoring of stacks and ducts

of any size and configuration.

CATM Combust ion Airf low Measur ing Station & VOLU-probe/SSTM

Traverse Probes. Air Monitor Power's duct mounted airflow measurement deviceshave been designed to accurately and repeatedly measure air mass flow in power plants.

The Combustion Air (CA) StationTM includes honeycomb air straightener to accurately

measure in shorter straight duct runs than any other flow measurement device. The VOLU-

probe/SSTMdelivers accurate airflow measurement performance in the form of an insertion

probe. Both devices feature Type 316 stainless steel flow sensing arrays.

Engineering & Testing Services. Air Monitor Power offers complete engineering and testing to analyze air and coaldelivery systems. Air Monitor Powers field testing services use 3D airflow traversing and Pf-FLOcoal flow measurement

systems for the highest possible accuracy. To ensure cost effective and accurate solutions, Air Monitor Power has full scale

physical flow modeling capability and in house Computational Fluid Dynamics (CFD). CFD analysis is used to analyze flow

profiles and design/redesign ductwork to improve overall performance. Full scale model fabrication and certified wind tunnel

testing is used to develop application specific products that will measure accurately where no standard flow measurement can.

Pf-FLOTM Pulverized Fuel Flow ManagementThe Pf-FLOTM system performs continuous and accurate fuel flow measurement in

pulverized coal fired combustion applications, providing boiler operators with the real-time

data needed to balance coal mass distribution between burners. Balanced fuel improves

combustion efficiency and lowers emissions while reducing in-furnace slagging, coal layout,

fuel slagging, and coal pipe fires.

VOLU-probe/SSTMStainless Steel Air flow Traverse Probes.Multi-point, self-averaging, Pitot-Fechheimer airflow traverse probes with integral airflow

direction correcting design. Constructed of Type 316 stainless steel and available in

externally and internally mounted versions for harsh, corrosive or high temperature

applications such as fume hood, laboratory exhaust, pharmaceutical, and clean room

production and dirty industrial process applications.



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The Pf-FLOIII pulverized coal flow measurement system, introduced

in 1999, provides reliable and accurate mass flow measurement

in pulverized coal flow applications. The system provides boiler

operators with real time data

of the amount of coal to each burner.Analogous to the automotive industry, the Pf-FLOIII system enables

coal fired power plants to advance beyond carburetion to fuel

injection.

Coal fired boilers require accurate pulverized fuel flow

measurement to balance coal mass distribution between burners.

Balancing the coal mass improves the burner-to-burner

stoichiometry, resulting in better plant performance and operating

efficiency. Equal coal mass distribution also reduces fuel delivery

issues, such as in-furnace slagging, coal layout, fuel slugging,

and coal pipe fires.

When Pf-FLO III is coupled with individual burner airflow

measurement, a boiler operator can use the system to fine tune

air-to-fuel ratios on a per burner basis. This makes the Pf-FLOIII

system a very capable NOx reduction and boiler performance

optimization tool.

Product Description

Pf-FLOIII TM

!!!!! Real time on-line pulverized coal flow measurement

!!!!! 5% accuracy, independently tested, and proven

!!!!! System measures full pipe cross-section

!!!!! Simple Commissioning. No need for extractive sampling or field

testing to calibrate

!!!!! Ensures safe boiler operation by detecting fuel delivery problems

!!!!! Assists in minimizing primary air while maintaining minimum

transport velocity, to reduce CO emissions

!!!!! Industrial construction for long term durability

!!!!! Combustion optimization tool proven to increase efficiency

and reduce emissions

!!!!! Replaces manual methods of coal flow measurement

Performance Features


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Pf-FLOFeatures

Pf-FLOIII TM

Stand-Alone Measurement. Each Pf-FLOIII coal flow transmitter

determines the mass flow rate and particle velocity of pulverized

coal, independent of a central processor and/or external inputs

such as mill feeder rate. The onboard microprocessor manages

the transmitter functionality and performs all data processing,

providing reliability with real-time performance.

Data Acquisition. The Pf-Vudata acquisition and archival software

provides the system operator with both dynamic and historic

graphical presentations of all measured parameters (particlevelocity, density, mass flow rate, and pipe temperature), logically

arranged by mill. Data can be selectively exported numerically into

spreadsheet software [in a delimited format] and/or continuously

communicated via an OPC or Modbus interface directly to a DCS or

PI platform.

Long Term Durability. All in-pipe mounted component s are

constructed of abrasion resistant Tungsten Carbide to ensure long

life, and are backed with a three year warranty.

Analog Communication. The Pf-FLOIII transmitter provides

dual 4-20mADC analog outputs for mass flow rate and particle

velocity measurements, user configurable for isolated or non-

isolated operation.

Local, Central & Remote Configuration. Utilizing the Pf-PRO

software utility, parameterization and calibration of each Pf-FLOIII

transmitter can be performed from a central PC over industry

standard Ethernet wiring, or locally at each transmitter utilizing a

laptop computer and a direct connect cable. With the addition of aphone connection to the central PC, each transmitter can be

monitored and configured remotely.

Simplified Installation. Included weld-in threaded inserts for

pipe mounted components, plus Factory prepared and labeled cables

provide for fast and error free installation of the Pf-FLOIII coal

flow system. Cable lengths of up to 50 allow for flexibility in the

mounting location of each transmitters NEMA 4 enclosure.


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Pf-FLOIII TM

Pf-Vusoftware provides access to all system parameters (mass

flow, velocity, density, and temperature) for each mill.

Pf-VuFeatures

Dynamic and historical data trending can be viewed through the

Pf-Vuinterface.

Screen Selection Dynamic Trend

Minimum Installation Requirements

!!!!! Suitable for installation in vertical, inclined or horizontal pipe.

!!!!! Recommended installation in vertical section of pipe right out of

mill discharge or first horizontal section of pipe within three to

five diameters of the upstream elbow.

!!!!! Pipe must not have any flanges in the measurement zone.

!!!!! Test ports can be located anywhere except in the measurement

zone between the two sensors.

!!!!! Fixed or variable orifices and coal valves must be located outside

the reflector rods.

!!!!! Orifices and coal valves should be installed downstream of the

last reflector rod.

!!!!! Pipe must not have ceramic lining within the reflector rods.

!!!!! Vertical down flow is not a suitable installation for the Pf-FLOIII

system.


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Pf-FLOIIITMPerformance Specification

Accuracy

5% of mass flow (absolute units), combining velocity and

density accuracies.

Power Consumption

42 VA at 120 VAC

24 VA at 24 VAC/DC

Measurement Update Rate

Single Pipe System. Mass Flow: 2 to 3 seconds

Dual Pipe System. Mass Flow: 4 to 6 seconds

Pf-FLOIIITMFunctional Specification

Microprocessor Based Functionality

All functions and operations are performed by the

Pf-FLOIIITMsystem on-board microprocessor.

Pf-FL OIIITMto PC / DAS Connectivity

ModBus / TCPIP via Ethernet

Analog Outputs

Dual 4-20mADC isolated or non-isolated outputs

Output 1: Mass Flow

Output 2: Velocity

Analog Inputs

Isolated or non-isolated 4-20mADC inputs for mill feed rate

and mill primary airflow. Inputs are for data analysis only

and are not required for mass flow measurement.

Rolling Average Filter

Adjustable from 1 to 10 values

Velocity Measurement Range

20 to 200 ft/s

Pipe Temperature Measurement Range

0 to 300F

Density Measurement Range

0 to 200 absolute units (approximately 0 to 0.08 lb/ft3,

dependent upon coal type)

Power Supply Requirement

120 VAC, 24 VAC or 24 VDC

Circuit Protection

Power input is fused and reverse polarity protected

Temperature Limits.

20F to 180F Storage

0F to 140F Operating

Enclosure

NEMA 4

Sensor Antenna and In-Pipe Components

Tungsten carbide construction

Threaded Inserts

Weld-in 5/8-18

Pf-FLOIII TM

Pf-FLOIIITM PC/DAS Functional Specification

Pf-Vu

WonderwareTMbased software for data display and

extraction to ExcelTM. [Optional] Pf-Vu/Plusto include

Burner Secondary Airflow Measurement.

Pf-PROSystem management software for local or central system

parameterization and commissioning.

Data Storage

Receive and archive data for all pipes: Density, Velocity,

Temperature, Mass Flow, Feeder, and PA.

Data Extraction

[Optional] OPC or Modbus communication of data to plant

DCS or PI system.

Remote Connectivity

PCAnywhereTM for remote operator access. Requiresphone connection.

Password Protection

Owner, Administrator, and Operator / User.


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125-196 (7/07)

Ai r Moni tor Power's Product Famil ies of Ai rf low Measurement & Services

IBAMTM Individual Burner Airfl ow Measurement

The IBAMTM Individual Burner Airflow Measurement probe is ideally suited for new or


can be obtained through accurate measurement of burner secondary airflow. The

IBAMTM

probe has been designed to accurately measure in the particulate laden, highoperating temperature conditions found in burner air passages.

CAMSTM Combustion Airf low Management SystemThe CAMSTM Combustion Airflow Management System has been designed to reliably

and accurately measure airflow in combustion airflow applications. The CAMSTM

contains the microprocessor based instrumentation to measure the airflow and

manage the AUTO-purge. The AUTO-purge is a high pressure air blowback system

that protects the duct mounted flow measurement device from any degradation in

performance due to the presence of airborne particulate (flyash).

Air Monitor Power's duct mounted airflow measurement devices have been designed

to accurately and repeatedly measure air mass flow in power plants. The Combustion

Air (CA) StationTMincludes honeycomb air straightener to accurately measure in shorter

straight duct runs than any other flow measurement device. The VOLU-probe/SSTM

delivers accurate airflow measurement performance in the form of an insertion probe.

Both devices feature Type 316 stainless steel flow sensing arrays.

CEMSTM Continuous Emissions Monitoring SystemAir Monitor Power's CEMSTM Continuous Emissions Monitoring Systems assist

in complying with the Clean Air Acts stringent emission measurement standards

and the requirements of 40 CFR 75. Air Monitor Power has assembled a cost

effective integrated system consisting of in-stack flow measurement equipment

and companion instrumentation to provide continuous, accurate, and reliable

volumetric airflow monitoring of stacks and ducts of any size and configuration.

Combust ion Air flow Measuring Station & VOLU-probe/SSTMTraverse Probes

Engineering & Testing Services. Air Monitor Power offers completeengineering and testing to analyze air and coal delivery systems. Air Monitor

Powers field testing services use 3D airflow traversing and Pf-FLOcoal flow

measurement systems for the highest possible accuracy. To ensure cost

effective and accurate solutions, Air Monitor Power has full scale physical

flow modeling capability and in house Computational Fluid Dynamics (CFD).

CFD analysis is used to analyze flow profiles and design/redesign ductwork

to improve overall performance. Full scale model fabrication and certifiedwind tunnel testing is used to develop application specific products that will

measure accurately where no standard flow measurement can.

Coal Flow Technology Licensed From:

P.O. Box 6358 Santa Rosa, CA 95406 P: 800-AIRFLOW F: 707-526-9970 www.airmonitor.com [email protected]


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Page 2 of 14

III. TRIAL SYSTEM

Before applying the coal flow technology with the other technologies for optimum NOxreduction, a trial would be performed at the Mayo Station. Mayo consists of twoboilers operating one turbine. Pf-FLO was installed in each of sixteen (16) burners forone of the two boilers. The goal was to achieve 10-15% NOxreduction using just thePf-FLO system. This low cost trial entailed renting a Pf-FLO system for the sixteenpipes. No adjustable coal valves were purchased. The objective would be to adjustburner airflows (though no airflow measurements were available) to the burners basedupon the coal mass flow in each pipe. Though no coal valves were purchased due tocost limitations for this trial, the auxiliary air on each of the four coal mills was used toact as an air curtain or restriction in each coal pipe. This allowed for better balancingof the coal pipes of each mill.

Though Pf-FLO yielded the coal flow to each burner, the airflow to each burner wasunknown. The O2grid in the backpass was used in lieu of airflow to help identify

fuel:air ratio imbalances. Burner air registers were adjusted accordingly. As a result,a 10% NOxreduction was achieved at full load and 15% reduction was achieved atreduced load. These tests were repeated on different days to ensure repeatableresults. In addition, the improved combustion led to a reduction in opacity for all testsand O2stratification was also minimized.

Through the Mayo trials, it was determined that individual burner airflow would behelpful in future installations. Individual burner airflow would allow the users to tuneairflow to match coal flows directly. In addition, a more effective means of moving coalflow between pipes was recommended.

IV. IMPLEMENTING A COMPLETE NOXCONTROL SYSTEM

Sutton 3 was selected for the integration of the lower cost NOxreduction systems. Inaddition to the air and fuel control, low NOxburner modifications and SNCR were to beimplemented at Sutton.

A. Coal Adjustment and Air Flow

Sutton 3 has Riley double ended Atrita mills. These mills are known to produceend to end imbalances. In addition, the output of each end of each mill would

split into two pipes through a riffle box. These riffle boxes are also known tocreate imbalanced coal flow.

Diverter dampers were designed by AMC and installed during the April-May 2005outage. The diverter dampers controlled the coal to each side of each mill. Inaddition, new adjustable (for coal imbalance) riffle boxes were purchased throughFWEC.

AMC specializes in combustion airflow measurement and has supplied individualburner airflow measurement systems (IBAMs) on several hundred low NOx


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Page 4 of 14

rich. For each strategy, each row of burners was given a fuel/air setpoint. Thecontrols system looks at 2-minute averages of fuel/air ratios. If a burners fuel/airratio is above or below its setpoint bymore than 10%, the secondary air disk ismoved open or close accordingly by an increment of 5%. Another 2-minuteaverage is then analyzed and changes are made accordingly.

The O2 across the back end improved and fuel air ratios are maintained. This

new control scheme would mean operators will spend less time trying to blindlyadjust burner air registers when there is a combustion problem (such as O2imbalance or high CO).

V. RESULTS SUMMARY

The Pf-FLO coal flow system combined with the IBAM burner airflow systems, coaldiverters, and riffle boxes exceeded expectations for NOxcontrol and othercombustion improvements (Better Boiler control, LOI, and O2) as outlined in the tablebelow.

PROJECT PERFORMANCE vs. GOALS

Modification Target Measured Remarks

Coal Flow and Air FlowBalancing (Air MonitorCorporation)

NOx< 0.595 lb/mmbtu(15% reduction in NOx)

NOx= 0.54 lb/mmbtu(23% reduction from0.7 lb/mmbtubaseline)

Measured values achieved April21, 2005 with domestic coal.Unit at Full Load 7 mill operation(pre-outage).

Combined Coal Flow andAir Flow Balancing (AirMonitor Corporation) andLow NOxBurnerModifications (FosterWheeler)

NOx


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Page 5 of 14

APPENDIX

SUTTON 3 PROJECT

The Pf-FLOIII coal flow measurement system was installed onto each of the 28burner lines at Sutton Unit 3 in February 2005.

The location of the sensors is in the horizontal pipe sections downstream of the riffleboxes. As shown below, the riffle boxes are to the lower right, the burners are to theleft of the riffle boxes.


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Page 14 of 14

Below is the control room screen showing desired/automatic fuel/air ratios.


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PF-FLO REFERENCE TEST AT THE MARTIN-LUTHER UNIVERSITY

HALLE-WITTENBERG

CONTENTS Page

1.

Introduction..................................................................................................... 12. Description of the Test Facilities..................................................................... 3

2.1 The Testing Plant ................................................................................... 3

2.2 The Pf-FLO Mass Flow Measurement.................................................... 4

2.2.1 Density measurement.................................................................. 4

2.2.2 Velocity measurement ................................................................. 5

2.2.3 Calculation of the Mass Flow....................................................... 6

2.3 Pf-FLO Test Configuration...................................................................... 6

2.4 The Test Medium.................................................................................... 8

2.5 Feeder Calibration.................................................................................. 9

3. Testing Procedure .......................................................................................... 11

4. Results ........................................................................................................... 14

4.1 Pf-FLO Measurement Accuracy ............................................................. 14

4.1.1 Absolute Deviation....................................................................... 15

4.1.2 Repeatability ................................................................................ 16

4.2 Influence of the Particle Size.................................................................. 17

4.2.1 Velocity Measurement ................................................................. 17

4.2.2 Density Measurement.................................................................. 19

4.2.3 Mass flow measurement.............................................................. 20

5. Abstract .......................................................................................................... 23


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2. Description of the Test Facilities

The reference test was carried out at the Merseburg test plant. The test facility is

designed with a closed loop for the particle flow and an open end for the transport air.

This arrangement ensures particle recycling via a cyclone back to the feeder without

significant particle mass loss, for re-introduction at a controlled rate/concentration.

For safety reasons the test plant was operated with glass beads of two different

diameters instead of pulverized coal. Particle load and transport air velocity were

varied during the test series in a range simulating that which naturally occurs with

pneumatically transported coal (see test matrix, Figure 3.1 and Table 3.1).

2.1 The Testing PlantThe test duct layout is drawn in Figure 2.1. Two rotary piston blowers, operating in

parallel and controlled by fan speed frequency converters, providing a velocity range

of about 46 to 92 ft/s for the transport air.

Cyclone

Rotary Valve

Screw Feeder

Bagfilter

Ch 3 Ch 2

Ch 1

Ch 0

Hopper

Air Outlet

16.5 ft.

10 ft.AirInlet

Fig. 2.1: Schematic drawing of the test plant

The particles are introduced to the airflow by a screw feeder, transported through the

pipe and separated in a cyclone. Out of the cyclone the separated particles are fed


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2.4 The Test Medium

The test plant could not be used with black coal for safety reasons. Therefore, glass

spheres were used, with such properties as particle size, dielectric constant, and

electrostatic charging similar to pulverized coal.

Typically 85 % 95 % by weight of pulverized coal particles downstream of the mills

classifier are smaller than 90 m and 0.3 % or less are bigger than 225 m. The two

glass particle sizes of 66 m and 225 m used for this test represent the main

fraction and the biggest possible size fraction of particles in coal pipes.

The manufacturer of the glass beads specifies a glass density of 158.6 lb/ft and an r

of 2.28 at visible light. The rmay be slightly different for microwaves due to

dispersion.

The dielectric properties of milled coal and the glass spheres were tested in a

microwave resonator chamber. It was found that the frequency shift in this

measurement was dependent upon the dielectric properties on the bulk density of the

pulverized medium. By calculating the frequency shift per mass, the influence of the

sphere packing were eliminated. The results are displayed in Table 2.1.

Medium

Bulk density

[lbs/ft]

Frequency shift/

mass [MHz/lb]

Glass spheres 88.1 124.1

Black coal (Primero) 35.8 200.1

Black coal (Blumenthal) 35.8 193.9

Black coal (Knurrow) 41.8 193.5

Table 2.1: Bulk density and frequency shift for fixed-bed powder

of pulverized black coal and glass particles

The frequency shift at the same mass flow caused by glass is about 2/3 of the tested

coal. Therefore, the expected frequency shift for the mass flow measurement will

only be about 1/3 less for glass than for coal with the same mass. This ensures a

good comparability between the test data obtained with glass particles used as the

test medium versus that which would have been obtained had coal been able to be

used for the test medium.

The density for raw coal is between 78.0 and 81.8 lbs/ft. Taking this density into

account, glass particles of the same size are about two times heavier than coal


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particles. The weight differential plus the shape of the particles, spherical for glass

and polyhedral for coal, give glass aerodynamic properties which result in a greater

velocity differential or slip between the airflow and the glass particles.

The electrostatic charging depends on particle collisions and particle conductivity.

The velocity measurement needs a certain amount of electrostatic charge to

correlate the sensor signals into a reliable time of flight measurement. Charging

signal strengths for both size glass beads and bead mixtures were sufficiently high to

obtain accurate time of flight measurements. Induced by the substantially greater

number of particle amount within the airflow, the signal strength of 66 m particles

was about five times higher than for the 225 m particles.

Gravimetric Particle Size Distribution

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 50 100 150 200 250 300

Particle size [m]

Rel.particledistribution

[%]

Fig. 2.4: Particle distribution as a function of particle size for the

50/50 mix of 66 m and 225 m particles

Beside the pure 66 m and 225 m particles, a 50/50 mix by weight was also tested.

Figure 2.4 shows the gravimetric distribution of particle sizes.

2.5 Feeder Calibration

To calibrate the feeder, glass beads were fed by the frequency controlled feeder into

a container for 30 seconds and their mass was weighed. This procedure was

repeated twice for each particle size in steps of 50 rpm from 0 to 350 rpm. The

average of both sets of measurements was used for the feeder calibration.


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The repeatability of the feeder calibration was then tested by 10 individual

measurements with the 66 m particles at 150 rpm. They were all in the range of

0.9 % by weight.

This was acceptable since the aim of the tests was not to examine the characteristics

of the screw feeder. And with all four sensor locations measuring physically the same

airflow/particle mixture, any scattering of the feeder is eliminated as a common

variable.

Feeder Calibration

0

.11

.22

.33

.44

.55

0 50 100 150 200 250 300 350 400

Feeder speed [rpm]

Massflow[lbs/s]

66 225 m

225 m

66 m

Fig. 2.5: Mass flow versus feeder speed for different particle fractions

The mass flow of the feeder is shown in Figure 2.5 for the specific particle fractions.

The mass flow at a particular feeder speed depends on the particle size distribution.

The mix of the two size fractions has the tightest packing and thus shows the highest

mass flow. The 66 m and 225 m particles have different mass flows since for

particles


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3. Testing Procedure

The test runs have been made under the aspect of realistic airflow velocities and

particle concentrations.

Within the capacity of the fan, three velocity levels were chosen at 72 ft/s, 82 ft/s, and

92 ft/s, representing normal transport velocities in utility plants. With constant air

velocities the feeder speed was varied between 0 - 300 rpm in steps of 50 rpm.

Particle Concentration Range

0

0.006

0.013

0.019

0.025

0.031

0.037

0.044

0.050

0 50 100 150 200 250 300 350

Feeder speed [rpm]

Concentration[lbs/ft]

Fig. 3.1: Range of pf-concentrations based on feeder mass flow and

transport air flow

The pf concentrations in utility plants usually range between 0.012 to 0.031 lbs/ft.

Figure 3.1 shows the range of the expected pf concentration based on the ratio of

feeder mass flow and the airflow during the tests.

Table 3.1 gives an overview of the different test runs: From the total number of 15

test runs there were six runs with the 66 m particles, six runs with the particle mix

and three runs with the 225 m particles.


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Particle Size Test Numbers

66 m I,VI II,V III,IV

225 m I II III

66 - 225 m mix I,IV II,V III, VI

72 ft/s 82 ft/s 92 ft/s

Gas Velocity

Table 3.1: Test run number for each particle size

The following diagrams illustrate the data acquired for all test runs: Diagram

Figures 3.2 and 3.3 show density and velocity measurement, and Figure 3.4 shows

the resulting mass flow of the 66 225 m particles of Test Number V. Each feeder

step was kept constant for at least 15 minutes to get about 20 individual

measurements. From the last 15 measurements of each feeder step the average was

taken and plotted against the feeder mass flow in Figure 3.5.

0

6

12

18

24

30

36

42

48

54

61

13:04

13:12

13:20

13:29

13:37

13:46

13:54

14:02

14:11

14:19

14:28

14:36

14:44

14:53

15:01

15:10

15:18

0

50

100

150

200

250

300

350

400

CH 0

CH 1

CH 2

CH 3

feeder

Densities 66 - 225 m, Test V

Density[a.u./

ft]

Feederspeed[rpm]

Fig. 3.2: Density measurement Fig. 3.3: Velocity measurement

0

500

1000

1500

2000

2500

3000

3500

4000

4500

13:04

13:11

13:19

13:26

13:34

13:41

13:49

13:57

14:04

14:12

14:19

14:27

14:34

14:42

14:49

14:57

15:05

15:12

15:20

0

50

100

150

200

250

300

350

CH 0

CH 1

CH 2

CH 3

feeder

Massflow[a.u./s]

Mass Flows 66 - 225 m, Test V

Feeders

peed[rpm]

Fig. 3.4: Resulting mass flow and feeder signal Fig. 3.5: Mass flow of feeder versus Pf-FLO

0

16

33

49

66

82

98

13:0

4

13:1

1

13:19

13:2

6

13:3

4

13:4

1

13:4

9

13:5

7

14:0

4

14:1

2

14:19

14:2

7

14:3

4

14:42

14:4

9

14:5

7

15:0

5

15:1

2

15:2 0

CH 0

CH 1

CH 2

CH 3

Velocities 66 - 225 m, Test V

Velocity[ft/s]

Mass Flow of Feeder vs.

Pf-FLO, 66 - 225 m, Test I - VI

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 198 397 595 793 992 1190 1389 1587

CH 0

CH 1

CH 2

CH 3

Pf-FLOMassflow

[a.u./s]

Feeder mass flow [lbs/hr]


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All test runs have been plotted as displayed in Figure 3.5. As there is only a constant

factor between [a.u./s] and [g/s], a unified y-axis scaling was used to help evaluate

the influence of different particle sizes (see also Figure 4.8).


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shifts is of the same order, it might be possible to distinguish between the two

velocities. In case of the particle mix the signal strength of the 225 m particles was

below the noise signal level of the 66 m particles. Therefore, it is obvious that only

the velocity of the 66 m particles has been measured. The error in relation to the

realistic particle size distribution is estimated in Section 4.2.3.

Velocities of the 225 m Particles

0

16

33

49

66

82

98

72 ft/s gas velocity 82 ft/s gas velocity 92 ft/s gas velocity

velocity[ft/s]

CH0

CH1

CH2

CH3

Fig. 4.4: Acceleration along the test duct of the 225 m particles

In the tests which measured 225 m particles only, channel 3 was found to have

higher velocities than the other channels. This can be explained by the position of

this sensor pair located at the end of the horizontal test duct with the longest straight

run after a bend (see Figure 2.1). This leads to a certain acceleration, especially for

the bigger sized particles.

Influence of Mass Flow on Velocity of the Particle Mix

67

72

79

85

92

98

0 397 793 1190 1587

Feeder [lbs/hr]

velocity[

ft/s]

CH 0

CH 1

CH 2

CH 3

Fig. 4.5: Influence of the mass flow on the velocity of the particle mix in Test IV-VI


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Figure 4.5 shows the influence of the mass flow on particle velocity. This effect, here

illustrated for the particle mix, is obvious when the averaged velocity of each feeder

step is plotted over the mass flow as it is done in Figure 4.5. Each bundle of the four

channels represents one step of the airflow velocity.

The higher the airflow velocity the higher the influence from pf load in the pipe.

Channel 2 with the shortest distance from a bend seems to be affected most. It is

assumed that this effect is related to particle interaction between 66 m and 225 m

particles, the latter having significantly lower velocities.

4.2.2 Density Measurement

Densities 66 m Particles, Test V

0

6.1

18.3

24.4

30.5

36.6

42.7

13:32

13:41

13:50

13:58

14:07

14:16

14:25

14:34

14:42

14:51

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Air Moniter