S-1688 Pneumatic stencil cleaner - Safe, environment-friendly, high quality and performance
A Cleaner Environment
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June 2015 | AWE International AWE International | June 2015 46 47 Case Study Tuneable diode laser spectrometry (TDLS) from Axetris Since the 1970s, legislators have regularly passed more and more stringent environmental laws requiring emissions control technologies to reduce the impact of emission sources on air pollution and global warming. Continuous emission control and monitoring Historically, the initial focus was on filtering the exhaust air from emission sources, which was followed by a focus on analysis of emission components pre- and post-filtering. The instruments used to control processes in a closed loop could not be used to quantify the quality of the filtering processes. Continuous emission monitoring systems (CEMS) are used as the main means to comply with air emission standards set by the governmental environment authorities. Facilities like coal or gas power plants or incinerators employ the use of CEMS to continuously collect, record and report the required emissions data. Regulations and standards The European Community has published several directives to harmonise the legislation on industrial emissions, in order to achieve a high level of protection for the environment and human health. These include the Large Combustion Plant Directive (LCPD, 2001/80/EC), Industrial Emissions Directive (IPPC, 2010/75/EU) and the Waste Incineration Directive (2000/76/EC). Comparable efforts are being undertaken all over the world. While the intensity of such efforts in the USA is similar to that in Europe, emerging countries such as China have started to reduce their emission footprint with greater efforts over the past years. “Axetris has chosen the new approach to TDLS and successfully developed a pre-calibrated OEM module carrying out a hot-wet measurement” The European Standard EN14181 describes the quality assurance procedures for CEMS in meeting the uncertainty requirements on measured values given by legislation. EN14181 had far-reaching consequences for regulators, equipment manufacturers, test houses and process operators. Three different quality assurance levels (QALs) are described: QAL1 for verifying the suitability of a system to its measuring task, QAL2 for the validation of the system following the installation in a specific plant and QAL3 for verification of control while operating. Selective catalytic reduction Selective catalytic reduction (SCR) is a method of converting nitrogen oxides (NOx) with the aid of a catalyst into nitrogen (N 2 ) and water. The exhaust gas is mixed with a reducing agent, typically ammonia (NH 3 ) or urea. One of the major challenges for SCR control is the determination of the correct NH 3 or urea flow under all process conditions. In general, this flow is controlled with a NOx measurement instrument. When ammonia is over-injected into the gas stream, however, high concentrations of ammonia emission (slip) can escape, which can also lead to degradation of the catalyst. For this reason, it’s becoming mandatory to continuously measure the ammonia concentration, maintaining the slip at levels below a few mg/m 3 . A Cleaner Environment Extractive TDLS The measuring principle can be divided into two major categories: extractive and in-situ. The advantage of the latter is that the measurement takes place in the main gas flow. There are several disadvantages, however, such as the difficulties to keep the windows clean in an unfiltered air, calibration and the influence of ambient conditions. Depending on the position on the stack, the maintenance of such instruments can be hard going. “the LGD F200-H NH3 module can be used for a certification range of 0 - 10 mg/m 3 NH 3 and 0 - 30% volume absolute humidity” Many extractive CEMS capture a sample from the stack, condition the sample by removing impurities and water, and transport the sample to an analyser mounted typically in a control room. For components like ammonia NH 3 or HCl that solve easily in water this is not the correct solution, as an unknown big part of the measure will be washed out before reaching the instrument. A much better solution is the use of a system including only heated components in contact with the air: filter, pipes, pumps and the instrument itself. The main technologies used in this set-up are fourier transform infrared (FTIR) spectroscopy, nondispersive infrared (NDIR) and tunable diode laser absorption spectroscopy (TDLAS). FTIR interprets a wide IR spectrum and so can detect several gases, but it is difficult to calibrate, to reduce the cross sensitivities and last but not least, this technology is rather complicated and expensive. With the advantages in laser design in the last decade it became possible to design TDLAS instruments in the near infrared range at reasonably low costs. These instruments measure one single rotational-vibrational line somewhere in the range of 700 to 2,500nm. Due to the use of 2f WMS method and referencing to the detected power level, these instruments are widely accepted as very stable, calibration free and without cross sensitivities to other air pollution components. Axetris has chosen the new approach to TDLS and successfully developed a pre-calibrated OEM module carrying out a hot-wet measurement, e.g. ammonia and humidity at 190°C. The technology increases performance, reliability and cost effectiveness - or simply enables new opportunities for OEM customers. The LGD F200-H NH 3 module can be used for a certification range of 0 - 10 mg/m 3 NH 3 (lower range) and 0 - 30% volume absolute humidity. n For further information visit www.axetris.com or contact [email protected] Case Study The Axetris LGD F200 is a fully calibrated TDLS module built for OEM integration, and currently available for gases such as NH 3 , HCl, CH 4 , CO 2 and H 2 O Laboratory lack of fit (linearity) test of two CEMS systems based on the Axetris LGD F200-H NH 3 Field test comparison with a reference FTIR system (daily average)
Transcript of A Cleaner Environment
June 2015 | AWE InternationalAWE International | June 201546 47
Case Study
Tuneable diode laser spectrometry (TDLS) from Axetris
Since the 1970s, legislators have regularly passed more and
more stringent environmental laws requiring emissions control
technologies to reduce the impact of emission sources on air
pollution and global warming.
Continuous emission control and monitoringHistorically, the initial focus was on filtering the exhaust air from
emission sources, which was followed by a focus on analysis of
emission components pre- and post-filtering. The instruments used to
control processes in a closed loop could not be used to quantify the
quality of the filtering processes. Continuous emission monitoring
systems (CEMS) are used as the main means to comply with air
emission standards set by the governmental environment authorities.
Facilities like coal or gas power plants or incinerators employ the use
of CEMS to continuously collect, record and report the required
emissions data.
Regulations and standardsThe European Community has published several directives to
harmonise the legislation on industrial emissions, in order to achieve
a high level of protection for the environment and human health. These
include the Large Combustion Plant Directive (LCPD, 2001/80/EC),
Industrial Emissions Directive (IPPC, 2010/75/EU) and the Waste
Incineration Directive (2000/76/EC). Comparable efforts are being
undertaken all over the world. While the intensity of such efforts in the
USA is similar to that in Europe, emerging countries such as China
have started to reduce their emission footprint with greater efforts over
the past years.
“Axetris has chosen the new approach to TDLS and successfully developed a pre-calibrated OEM module carrying out a hot-wet measurement”
The European Standard EN14181 describes the quality assurance
procedures for CEMS in meeting the uncertainty requirements on
measured values given by legislation. EN14181 had far-reaching
consequences for regulators, equipment manufacturers, test houses
and process operators. Three different quality assurance levels (QALs)
are described: QAL1 for verifying the suitability of a system to its
measuring task, QAL2 for the validation of the system following the
installation in a specific plant and QAL3 for verification of control
while operating.
Selective catalytic reductionSelective catalytic reduction (SCR) is a method of converting nitrogen
oxides (NOx) with the aid of a catalyst into nitrogen (N2) and water. The
exhaust gas is mixed with a reducing agent, typically ammonia (NH3)
or urea. One of the major challenges for SCR control is the
determination of the correct NH3 or urea flow under all process
conditions. In general, this flow is controlled with a NOx measurement
instrument. When ammonia is over-injected into the gas stream,
however, high concentrations of ammonia emission (slip) can escape,
which can also lead to degradation of the catalyst. For this reason,
it’s becoming mandatory to continuously measure the ammonia
concentration, maintaining the slip at levels below a few mg/m3.
A Cleaner Environment
Extractive TDLSThe measuring principle can be divided into two major categories:
extractive and in-situ. The advantage of the latter is that the
measurement takes place in the main gas flow. There are several
disadvantages, however, such as the difficulties to keep the windows
clean in an unfiltered air, calibration and the influence of ambient
conditions. Depending on the position on the stack, the maintenance
of such instruments can be hard going.
“the LGD F200-H NH3 module can be used for a certification range of 0 - 10 mg/m3 NH3 and 0 - 30% volume absolute humidity”
Many extractive CEMS capture a sample from the stack, condition the
sample by removing impurities and water, and transport the sample to
an analyser mounted typically in a control room. For components like
ammonia NH3 or HCl that solve easily in water this is not the correct
solution, as an unknown big part of the measure will be washed out
before reaching the instrument.
A much better solution is the use of a system including only heated
components in contact with the air: filter, pipes, pumps and the
instrument itself. The main technologies used in this set-up are fourier
transform infrared (FTIR) spectroscopy, nondispersive infrared (NDIR)
and tunable diode laser absorption spectroscopy (TDLAS). FTIR
interprets a wide IR spectrum and so can detect several gases, but it
is difficult to calibrate, to reduce the cross sensitivities and last but not
least, this technology is rather complicated and expensive.
With the advantages in laser design in the last decade it became possible
to design TDLAS instruments in the near infrared range at reasonably
low costs. These instruments measure one single rotational-vibrational
line somewhere in the range of 700 to 2,500nm. Due to the use of 2f
WMS method and referencing to the detected power level, these
instruments are widely accepted as very stable, calibration free and
without cross sensitivities to other air pollution components.
Axetris has chosen the new approach to TDLS and successfully
developed a pre-calibrated OEM module carrying out a hot-wet
measurement, e.g. ammonia and humidity at 190°C. The technology
increases performance, reliability and cost effectiveness - or simply
enables new opportunities for OEM customers. The LGD F200-H NH3
module can be used for a certification range of 0 - 10 mg/m3 NH3
(lower range) and 0 - 30% volume absolute humidity. n
For further information visit www.axetris.com or contact [email protected]
Case Study
The Axetris LGD F200 is a fully calibrated TDLS module built for OEM integration, and currently available for gases such as NH3, HCl, CH4, CO2 and H2O
Laboratory lack of fit (linearity) test of two CEMS systems based on the Axetris LGD F200-H NH3Field test comparison with a reference FTIR system (daily average)
