22/01/2016

Pulp and Paper industry designs QAL 181 WS dust monitor as the must to have

Besides being the only system totally certified on the market, the QAL 181 WS dust monitor is suitable for measuring particulate emissions from wet scrubbers (alkaline scrubbers) and other processes where the flue gas falls below dew point (cold stack conditions) or water droplets are present.


In 2015, one of the biggest European Pulp and Paper Company with facilities in France, launched a comparative study for the renewal of its dust emissions monitors installed on its production sites. The operator did not only required to meet the regulatory requirements but was looking for a turnkey system, using the most reliable technology, the most economical and the most adapted solution to its very dusty and humid process. His choice was naturally inclined towards the QAL 181 WS particulate analyzer, manufactured by PCME Ltd (British subsidiary of Environnement SA), for which reliability and reduced maintenance operations were the key objectives of the development of the most comprehensive Certified dust analyzers range in the world.

Besides being the only system totally certified on the market, the QAL 181 WS dust monitor is suitable for measuring particulate emissions from wet scrubbers (alkaline scrubbers) and other processes where the flue gas falls below dew point (cold stack conditions) or water droplets are present. The system uses an advanced ProScatter™ light scatter sensor (PCME QAL 181) which itself is certified by TUV certified to EN 15267-3 with QAL 1 as defined by EN 14181 with a certification range of 0 – 15 mg/m3. The system will operate reliably in the flue gas conditions found after wet FGD and wet collectors in the Pulp and Paper, Metal and Chemicals industry where particulate levels are higher and the instrument is able to cope with potentially more contaminating conditions.wet_stack_particulate_monitor_QAL181WS_s

Typical wet stack applications:

  • Applications requiring QAL1 approved systems for wet stack monitoring
  • For applications with corrosive flue gas (e.g. wet FGD plant) an enhanced corrosion resistant version is available
  • Waste Incineration plant with wet scrubbing abatement plant and WESPs
  • Pulp and Paper Recovery boilers
  • Metallurgical and chemical processes fitted with wet scrubbers…

The extractive instrument QAL 181 WS takes a representative continuous sample from the stack, heats this well above dew point to evaporate water droplets and then measures the particulate concentration under dry conditions. This extractive approach with heating overcomes the problems of interference from condensation and water droplets associated with using in-situ particulate monitors after wet collectors.

 

 

 

European regulatory requirements for the Production of Pulp, Paper and Board:

Source of the informations below : “Industrial Emissions Directive 2010/75/EU (Integrated Pollution Prevention and Control) / Best Available Techniques (BAT) Reference Document (full document here)

“Monitoring of key process parameters and of emissions to water and air

BAT 9. BAT is to carry out the monitoring and measurement of emissions to air, as indicated below, on a regular basis with the frequency indicated and according to EN standards. If EN standards are not available, BAT is to use ISO, national or other international standards which ensure the provision of data of an equivalent scientific quality.

 

Parameter Monitoring frequency Emission source Monitoring associated with
a NOx and SO2 Continuous Recovery boiler BAT 21BAT 22BAT 36BAT 37
Periodic or continuous Lime kiln BAT 24BAT 26
Periodic or continuous Dedicated TRS burner BAT 28BAT 29
b Dust Periodic or continuous Recovery boiler (kraft) and lime kiln BAT 23BAT 27
Periodic Recovery boiler (sulphite) BAT 37
c TRS (including H2S) Continuous Recovery boiler BAT 21
Periodic or continuous Lime kiln and dedicated TRS burner BAT 24BAT 25BAT 28
Periodic Diffuse emissions from different sources (e.g. the fibre line, tanks, chip bins, etc.) and residual weak gases BAT 11BAT 20
d NH3 Periodic Recovery boiler equipped with SNCR BAT 36

 

Dust emissions

BAT 23. In order to reduce dust emissions from a recovery boiler, BAT is to use an electrostatic precipitator (ESP) or a combination of ESP and wet scrubber.

BAT-associated emission levels for dust emissions from a recovery boiler

Parameter Dust abatement system Yearly averagemg/Nm3 at 6 % O2 Yearly averagekg dust/ADt
Dust New or major refurbishment 10 – 25 0,02 – 0,20
Existing 10 – 40 (25) 0,02 — 0,3 (25)

BAT-associated emission levels for dust emissions from a lime kiln

Parameter Dust abatement system Yearly averagemg/Nm3 at 6 % O2 Yearly averagekg dust/ADt
Dust New or major refurbishments 10 – 25 0,005 – 0,02
Existing 10 – 30 (30) 0,005 – 0,03 (30) “