Extraction systems - your health-supporting, clean and sustainable solution

Basics of extraction technology

What is an extraction system? 

When working with materials that produce waste substances, extraction systems help to remove and/or separate them. Waste materials can be produced, for example, when spraying adhesives. This can result in overspray, i.e. a material mist that does not reach the workpiece. Extraction systems capture this mist and thus protect against substances that may be harmful to health.

Operating and testing extraction systems

  • Before commissioning an extraction system, an explosion safety test must be carried out (technical test & order test by qualified persons).
  • Annually a functional test
  • Every 3 or 6 years a technical or technical + organizational test must be carried out by a competent person.

We can offer the tests in each case.

Standards, laws and information

For the safe operation and the avoidance of health risks there are the following standards and regulations:  

  • Machinery Directive 2006/42/EC
  • EN 16985:2019 Paint booths for organic coating materials - Safety requirement.
  • DGUV 209-046 Painting rooms and equipment for liquid coating materials; structural facilities, fire and explosion protection, operation; as of August 2016

The extraction systems offered by WALTHER Pilot comply with valid laws, regulations, standards and directives.


Extraction systems with dry separation

In dry separation, the overspray is bound and then filtered. This is separated from the air with the aid of filter mats. The filter mats are multilayered so that the overspray does not stick to the filter and a high absorption capacity and thus a long service life can be guaranteed. 


  • Different design of separator filters possible
  • Low investment costs (cheaper than wet separators)
  • Easy handling
  • Applicable from small to large overspray quantities
  • ATEX design standard (zone 2)
  • Simple and inexpensive disposal
  • Well suited for adhesives
  • Low energy consumption
  • No regulations according to 42. BlmSchV - "Legionella regulation"


  • Wear parts (follow-up costs filter)
  • Fire risk with self-igniting paint systems
  • Possibly higher downtimes for filter changes
  • Changing suction conditions due to dirty filters

With dry separation, you save energy and costs through low-resource filter material. Depending on the disposal method, you can classify the used filter mats as "residual waste" (so disposal is correspondingly inexpensive).

In contrast to wet scrubbing, the required water is not needed - thus the growth of germs and molds is eliminated. In addition, you significantly reduce the noise level. At the same time, corrosion of the booth structure and the costly replacement of the water are reduced.

Extraction systems with wet separation

The operating principle of wet separators is to bring the particles dispersed in the raw gas stream into contact with a scrubbing liquid in order to bind them therein and then to separate the resulting particle-liquid mixture from the air stream. 

Wet separators are particularly suitable for sticky or highly flammable paints and aerosols. 

For wet separation to be effective, it is necessary to create as large a phase interface as possible as a contact surface between the scrubbing liquid and the gas to be cleaned.


  • Fire risk is reduced to a minimum (dust and ignition sources are wetted with water)
  • No filter wear (filter medium: water)
  • Dust accumulation in the painting area is significantly reduced 
  • Filtering is largely self-cleaning
  • No change in extraction performance due to added filters
  • The regulations in the TA AIR (Technical Instructions on Air Quality Control) on permitted dust quantities are simply adhered to. 
  • When using an automatic paint sludge disposal system, even very high paint quantities can be processed without any problems
  • Self-igniting paint systems can be processed without risk


  • High humidity in the exhaust air (due to recirculation) 
  • Risk of rust on components of the wet separator (water vortex must be generated for separation)
  • Dust (e.g. plastic) may be washed up
  • Lower separation efficiency to the dry system (high separation efficiency requires a lot of energy)
  • High pressure drop
  • Wear part of e.g. nozzles and water pumps
  • Expenditure for waste water and sludge disposal
  • Due to possible contamination, appropriate chemistry must be used
  • Regulations according to 42. BlmSchV "Legionella Ordinance" must be observed