CODEL Total Solutions - Total Confidence CODEL International Ltd Station Road, Bakewell, Derbyshire DE45 1GE England Tel: +44 (0) 1629 814 351 Fax: +44

CODEL

Total Solutions - Total Confidence

CODEL International LtdStation Road, Bakewell,Derbyshire DE45 1GEEnglandTel : +44 (0) 1629 814 351Fax : +44 (0) 8700 566 307e-mail : [email protected] : www.codel.co.uk

CODEL

Continuous Emissions Monitoring

Customer requirements for continuous emissions monitoring

• Measurement of all pollutant gases

• Measurement of solids emissions

• Measurement of complementary parameters

• Measurement to comply with legislation

• Secure data presentation

• Maximum reliability

• Low cost of ownershipCODEL

• Fully integrated system

• Seven gas species in a single analyser

• Particulate measurement

• Pollutant gas flow measurement

• Automatic data normalisation

• Five-year data logging & reporting

• Automatic calibration verification

CODEL

CODEL SmartCEM

Gaseous species• Carbon monoxide CO• Nitric oxide NO• Nitrogen dioxide NO2• Sulphur dioxide SO2• Hydrogen chloride HCl• Methane CH4• Carbon dioxide CO2• Water vapour H2O

CODEL

Available techniques for continuous gas analysis

• Infrared spectroscopy• Ultraviolet spectroscopy• Electrochemical cell• Solid electrolyte cell• Paramagnetic • Tuneable diode laser• Chemiluminescence• Flame ionisation devices

CODEL

Infrared spectroscopy

CODEL

Suitable for measuring many different species

wavenumber = 1/wavelength in cm = 10000/wavelength in μm


CODEL



H2OH2O and CO2


CODEL

CO



H2OH2O and CO2


CODEL

CO NO



H2OH2O and CO2


CODEL

SO2 CO NO



H2OH2O and CO2


CODEL

SO2 CO2 CO NO



H2OH2O and CO2


CODEL

SO2 CO2 CO NO



CH4

H2OH2O and CO2


CODEL

HCl SO2 CO2 CO NO



CH4

H2OH2O and CO2


CODEL

CH4NO2 HCl SO2 CO2 CO NO



H2OH2O and CO2

Carbon Monoxide CO

CODELwavenumber = 1/wavelength in cm = 10000/wavelength in μm

Live and Reference measurements

• Particles in the gas

• Variations in the transmitted energy

• Contaminated optical surfaces

CODEL

It is necessary to separate the infrared energy absorbed by the measured gas from the energy modified by other effects such as:

Multiple measurements in a single analyser

infrared detector

Pairs of live and reference optical filters are positioned sequentially in front of the detector


infrared detector



infrared detector



infrared detector


Application of IR spectroscopy

• Conventional cold extractive

• Conventional hot extractive

• Extractive with permeation dryer

• Open path cross-duct

• In-situ diffusion probe

• Heavy duty hot extractive

CODEL

Conventional cold extractiveSimple probe with pre-filtersCondensate removed

at probeSimple sample linesx Some gases are absorbed

in the condensatex Long sample lines can freezex Major maintenance required

if any water or solids reach the delicate analysers

CODEL

CO

NO

NO2

Dryers & filters

SO2

Condensate drain

Free-standing analyser cabinet in control room

Conventional hot extractiveHeated probe with pre-filtersGases held above dewpoint

in heated sample line Analyser cabinet must be

in control room with long expensive sample lines

Major maintenance required if heated sample lines fail and any water or solids reach the delicate analysers

CODEL

CO

NO

NO2

Final filters

SO2

Free-standing analyser cabinet in control room

Extractive with permeation dryerProbe with pre-filter and

integral permeation dryerWater vapour removed

at probeSimple sample lines Requires clean compressed

air dried to -20degC Major maintenance if water or

solids reach the analysers No water vapour measurement

for normalisationCODEL

CO

NO

NO2

Final filters

SO2

Dry air in

Wet air out

Tx Rx

Open path cross-ductSimple installationNo corruption of gasesSingle or multiple species Performance cannot be

audited against test gases Performance depends on

available measurement path Variations in dust level and optical

alignment can limit measurement sensitivity

CODEL

TxRx

CODEL in-situ diffusion probeFiltered measurement chamber

suitable for high dust levelsSimple installationNo corruption of gasesSingle or multiple species

plus H2OPerformance can be audited

against test gasesFixed optical alignmentMaximum reliability

CODEL

CODEL

CODEL G-CEM4000 gas analyser

CODEL heavy duty hot extractive In-duct probe with pre-filterGases held above dewpoint

in heated sample lineMultiple species plus H2O

Performance can be audited against test gases

Robust folded beam analyser requires minimal pre-conditioning

Increased measurement sensitivityMaximum reliability CODEL

Free-standing field-mounted analyser

CODEL G-CEM4100 gas analyser

Particulate measurement

Particles emitted from a combustion process include smoke, soot, ash & carried-over process materials (such as cement).

All of these particles are visible. They can be measured by looking at how much they absorb and scatter visible light.

CODEL

Particulate legislation

• Ringelmann number

• Opacity

• Smoke density

• Extinction

• Dust density in mg/m3

Requirements for expressing the amount of solids emitted from a process can vary dramatically for different processes and in different countries

CODEL

RingelmannA simple manual assessment of the appearance

of the plume against a standard chart graded white to black in 6 steps (Ringelmann 0 – 5)

CODEL

Continuous measurementsFor continuous measurement the energy

absorbed and scattered by the particles inside the exhaust duct can be expressed as:

Transmittance T = Ir/Io

Transmitted energy Io

Received energy Ir

CODEL

Opacity/Smoke densityThis is the simplest continuous measurement.

It is the opposite of transmittance expressed as a percentage. %opacity = (1-T)x100

This is the measurement preferred by US EPA

Transmitted energy Io

Received energy Ir

CODEL

Opacity

With a uniform dust concentration the opacity measured depends on the measured path.

CODEL

% opacity

% opacity

% opacity

Continuous dust monitoring techniques

CODEL

• Single pass transmissometer

• Double pass transmissometer

• Double beam transmissometer

• Optical scatter

• Triboelectric probe

Single pass transmissometer

Simple low cost techniqueHigh efficiency air purges to keep windows clean Cannot differentiate between gas-borne particles

and window contamination Cannot detect misalignment errors

CODEL

Beam splitter

Light source

Control detector

Measurement detector

Double pass transmissometer

CODEL

Auto-collimating

reflectorLight source

Detector

Zero point reflector

Air purges to keep windows cleanZero check reflector in transceiver unit Window contamination check on transceiver only Non-linear due to back scatter from the particles Cannot detect misalignment errors

Mirror

Double beam transmissometer - measuring

CODEL

High efficiency air purges keep windows cleanAlternate, bi-directional measurement provides

automatic misalignment checkMeasures across entire duct section

Rotary valve with integral mirror

Light source Detector

Mirror Beam splitter

Double beam transmissometer - contamination check

CODEL

Protected mirrors check individual contamination on both transceivers

Rotary valves protect transceivers during purge air or power failure

Mirror rotated into optical path

Light source Detector

Mirror Beam splitter

Light source

Detector

Back, forward or side scatter

CODEL

High sensitivityCan be built into a probe Measures in a very small

zone – local to duct wall Measured zone not

consistently representative In-duct reflections cause zero errors Unsuitable for large ducts or high levels

Measures light reflected from illuminated particles

Triboelectric probe

CODEL

Simple low cost probeHigh sensitivityEasy to install Highly cross-sensitive to

many operating parameters Measurement is flow-dependent Unsuitable for large ducts

Measures electrical charge transfer as particles collide with the probe

Hot gas velocity measurement techniques

CODEL

• Pitot tube

• Thermal anemometer

• Bi-directional ultrasonic

• Triboelectric correlation

• Infrared correlation

Pitot tube

CODEL

Simple manual techniqueSingle or multi-point Automated systems are

prone to blockage Unsuitable for irregular,

cyclonic or angular flow Unsuitable with high level

particulates or aerosols Complex installation

Type ‘L’ Pitot tube

Differential pressureVelocity

pressure

Static pressure

Measures the velocity pressure produced at an orifice facing into the flow.

Thermal anemometer

CODEL

Flue gases cool a hot wire held in the gas stream. The amount of cooling is a function of the gas temperature, gas composition and velocity.

Simple installationSingle or multi-point Unsuitable for ducts with

high spatial variations Affected by condensates

and dust build-up Non-linear outputs need site

calibration

Bi-directional ultrasonic

CODEL

Measures the difference between the transit time of sonic pulses transmitted upstream and downstream Average measurement across

entire duct Transceivers must be purged

to keep them cool and clean Complex install and service

– especially on large ducts Complex end effects Errors due to secondary

reflections and vibration

Correlation velocity measurement

CODEL

Measures the offset (equal to the transit time T) between signals from 2 separated detectors.

time

Τ Τ

Triboelectric correlation

CODEL

Measures the transit time between signals from two close-coupled triboelectric probes

Simple installation Unsuitable for ducts with high

spatial variations Affected by condensates

and dust build-up Unsuitable for turbulent flow Unsuitable for large ducts Close-coupled probes prone to

bridging with high dust burdens

Infrared correlation

CODEL

Measures the transit time between signals from two separated bulk infrared detectors

Simple installationAverage across entire ductSuitable for high temperatures High efficiency air purgesUnaffected by condensates

and dust build-upSuitable for turbulent flowSuitable for large or small ducts

CODEL

CODEL V-CEM 5000 flow monitor

Data normalisation

CODEL

• Changes in temperature • Changes in absolute pressure• Excess air• Water vapour

International legislation demands that any dilution at the point of measurement must be corrected. The measurement can be diluted by:

It is necessary to measure these complementary parameters and apply the appropriate correction. This is known as normalisation. Normalised values are in mg/Nm3

Data formats

CODEL

Gases• ppm• mg/m3

• mg/Nm3

• kg/hr

With the necessary complementary measurements CODEL analysers can present data in the following formats to suit all legislative and plant requirements

Particulates• opacity• extinction• mg/m3

• mg/Nm3

• kg/hr

System integrationIn any CEM system it is vital that normalisation and operating data are shared by all analysers.

CODEL analysers are designed to communicate with each other using a series of robust bi-directional data highways.

One highway distributes data between all analysers on the same stack. Another highway can be connected to a remote station for central data & diagnostic presentation and control via a PC.

This central PC can be interrogated and controlled via a telephone modem or broadband internet link.

CODEL

Typical CODEL SmartCEM layout

CODEL

Typical CODEL SmartCEM layout

CODEL SmartCEM data loggingMeasured and normalised data in many formats

CODEL

• Real time values • All data formats• Digital & analogue

presentation• Normalisation data• User-configurable

spans & alarms• Up to 12 channels in

up to 12 groups

CODEL

CODEL SmartCEM data loggingHistorical data in many formats

• Instant access to >5yrs historical data

• Customised reports• 3 levels of security• User-configurable

spans and alarms• Multi-user networking• System diagnostics• QAL3 reporting

CODEL

Total Solutions - Total Confidence

CODEL International LtdStation Road, Bakewell,Derbyshire DE45 1GEEnglandTel : +44 (0) 1629 814 351Fax : +44 (0) 8700 566 307e-mail : [email protected] : www.codel.co.uk

Documents

CODEL Total Solutions - Total Confidence CODEL International Ltd Station Road, Bakewell, Derbyshire DE45 1GE England Tel: +44 (0) 1629 814 351 Fax: +44