ESP Charging Efficiency Studies

Besides being able to measure particle size distribution and concentration in real-time, the ELPI®+’s unique ability to measure particle charge makes it well suited for ESP charging efficiency measurements. This allows accurately analyzes how ESP charging efficiency is affected by flue gas conditions and PM resistivity. The ELPI®+ can detect both negative and positive charge carried by the particles and it gives the charge size distribution in 14 size classes. This allows real-time determination of the ESP charging efficiency for different sized particles from 6 nm up to 10 µm.

 

ELPI®+ setup options

The setup options in emission measurements include direct sampling from the emission source into the High Temperature ELPI®+, or use of ELPI®+ with a well designed sample conditioning unit. The choice between direct sampling and sampling via a sample conditioning unit depends mainly on the particle concentration in  the sample and how much it should be diluted. If measurements are made before flue gas cleaning and treatment devices it is recommended to use a dilution system except in case natural gas is used as fuel. Dekati provides wide range of state-of-the art solutions for particle sample conditioning, e.g. the Dekati® Diluter and Dekati® Fine Particle Sampler are widely used in combustion emission studies. Besides standard dilution solutions, Dekati also provides custom made solutions for extreme sample conditions such as temperatures up to 1000 °C.

 

Comparison of different setups:

Maximum sample concentration depends on particle size.

High Temperature ELPI®+

  • Sample is led directly from the emission source to the ELPI®+ with e.g. a heated sampling line
  • ELPI®+ impactor and charger are heated up to the sample temperature, max 200 °C
  • High Temperature ELPI®+ especially suitable for sampling from wet stacks and low concentrations
  • Simple, robust setup
  • Can also be combined with any Dekati® Sample Conditioning device.
  • Isokinetic sampling probes available for different flow velocities
  • Dekati® Cyclone available for the setup for removal of >10 µm particles

 

Dekati® Diluter setup with High Temperature ELPI®+

  • Single heated Dekati® Diluter connected directly into High Temperature ELPI®+ inlet
  • Suitable for sample temperatures up to 450 °C.
  • Dilution temperature 0 – 200 °C
  • Dilution factor 8 - 50
  • Robust and easy to use dilution system – no moving parts and all stainless steel construction. Does not wear out even in continuous use.
  • Dekati® Cyclone available for the setup for removal of >10 µm particles
  • Isokinetic sampling nozzles available for different flow velocities

 

Dekati® Double Diluter setup with ELPI®+

  • Two Dekati® Diluters connected in series with the first dilution stage heated up to 450 °C.
  • Suitable for sample temperatures up to 450 °C
  • Diluted sample in room temperature at the ELPI®+ inlet
  • Dilution factor 64 nominal, available up to 2500
  • Robust and easy to use dilution system – no moving parts and all stainless steel construction. Does not wear out even in continuous use.
  • Dekati® Cyclone available for the setup for removal of >10 µm particles
  • Isokinetic sampling nozzles available for different flow velocities

 

Dekati® Fine Particle Sampler with ELPI®+

  • Dekati® FPS stack measurement setup including volatile control with heated dilution, pre-cut cyclone and isokinetic sampling
  • Sample in room temperature in the ELPI®+ inlet
  • Allows measurement of primary or primary+secondary emissions by using either heated or cooled setup.
  • Suitable for sample temperatures up to 600 °C.
  • Software controlled, versatile sampling system – adjustable dilution factor (20-200) and dilution temperature (0-350 °C)
  • Capability to measure from high/low pressure (750-2000 mbar abs) & temperature (0-600 °C) & concentration
  • Control of all features from a user-friendly PC-software
    • Continuous monitoring and control of dilution parameters – details of the dilution process can be analyzed after the measurement
    • Real-time dilution factor calculation
  • Stainless steel probe construction with no moving parts – no wear over long term use

 

Customized setups

In addition to standard Dekati® Sample Conditioning Solutions, Dekati is also able to offer custom made sample probes and dilution solutions for extreme conditions. Please contact Dekati for options and details.