Wet extraction in industry

Both dry separators and wet separators are suitable for separating and filtering dust or chips from the air. Which extraction system is optimal for your application depends on various factors: Process, medium, installation site as well as specific regulations for fire and explosion protection.

Functionality wet separator

In addition to dry dust extractors and smoke filters, wet separators are often used in industrial exhaust air purification. While dry extraction systems clean the air containing dust via several filter levels, wet separators use water to filter the substances out of the air.

The contaminated process air is drawn through either a water basin, a water wall or a water vortex. The particles are bound in the water by this technique and any remaining fine dust is separated in a HEPA H14 filter. The cleaned air can then be fed back into the hall or outside. Instead of dry dust, industrial sludge remains here as so-called discharge, which must be disposed of in accordance with regulations.

Efficient disposal of sludge discharge

Due to the innovative design of our sludge containers, the water is separated from the sludge by a sieve and can be fed back into the wet separator via an optional feed pump. This reduces water and disposal costs many times over and protects the environment. On average, up to 5,200 L of water can be saved per year. The remaining sludge can be disposed of more economically in accordance with local regulations.


Water recovery = less water, less costs, more environmental protection.

Dry extraction or wet extraction?

Whether a wet separator or dry dust extractor is suitable for your application depends on the nature of the material, the quantity and the physical properties.

Pros and cons
Wet extraction

  • Minimal fire risk

  • Inexpensive purchase

  • Low filter wear

  • Ideal for sticky, sparking
    and wet materials

  • Higher cleaning and maintenance effort

  • Outdoor installation not possible
    due to danger of freezing

  • Higher disposal costs
    of the discharge

Areas of application

Wet separators or wet scrubbers are particularly suitable for processes and substances that are associated with high levels of flying sparks, are sticky, moist, flammable or explosive (ATEX regulations). Grinding, deburring or sawing aluminum releases dusts and chips that must be safely extracted and filtered to comply with occupational health and safety regulations and environmental protection.

This process is also called wet dedusting and is used in a wide variety of sectors such as the automotive industry, mechanical engineering, the food industry or other metalworking companies.

  • Metalworking
  • Food
  • Stone and earth
  • Pharmacy
  • Recycling
  • Plastics
  • Automotive
  • grinding, polishing
  • Sawing, cutting, separating
  • Machining, milling
  • Decanting, filling, mixing
  • Flammable and/or explosive dusts
  • Dusts of aluminum, magnesium, steel, titanium
  • Wet or sticky dusts
  • Leather, rubber and plastic abrasion
  • Fibers, lint, textile dusts
  • Chips

Wet separator for aluminum dust

Machining aluminum can produce an explosive dust-air mixture. Wet separators offer a safe and reliable extraction solution for aluminum, stainless steel and other metals through the technical use of water.


What is a wet separator?

Wet separators or wet scrubbers are used for exhaust air purification in industry and filter dusts, chips, aerosols and other particles from the contaminated process air. In contrast to dry extraction, water is used as the filter medium in wet extraction. Pollutants and particles are drawn into the extraction system with the process air, bound by the water and separated. For carcinogenic dusts and fine dusts, additional HEPA H14 filters are used as a second filter level, which also filter viruses, pollen and mold spores. The cleaned process air can then be fed back into the production hall in recirculation mode or as exhaust air to the outside.

How does a wet separator work?

In wet separators, water is used to separate dust, chips and other particles. The water acts as a filter as particles from the polluted process air combine with the water droplets. The air is first sucked by a fan into a water vortex, a water wall or a water basin and then passes through further filter stages in the extraction system. All ABSAUGWERK wet separators have a specially developed stainless steel metal mesh in the second filter stage which separates the moisture from the cleaned air. When processing carcinogenic substances such as stainless steel dusts, we use an additional HEPA H14 filter as a third filter stage, which also effectively filters fine dusts and particles of 0.001 µm such as viruses, pollen or mold spores.

What substances does a wet separator filter?

  • Flammable dusts
  • Explosive dusts
  • Stainless steel dusts/steel dusts
  • Chips
  • Metal dusts (aluminum, magnesium, titanium)
  • Plastic, rubber
  • Fibers, lint
  • Wet dusts
  • Sticky powder

The areas of application for wet separators are as varied as the technologies. Not every wet separator is equally suitable for all types of dust, powder or chips. When selecting the right dust collection solution, we consider numerous parameters to ensure you an economical and sustainable extraction system.

When are wet separators used?

Wet separators are particularly suitable for filtering flammable, explosive, sticky, fibrous or moist media (dusts, fibers, powders and much more). The filter medium water extinguishes sparks and reduces fires or dust explosions. Industrial exhaust systems are subject to so-called ATEX directives (ATmosphères EXplosibles), which require a special design and technical components.

Wet deduster are used in a wide variety of industries for production processes such as grinding, polishing, cutting, cutting off.

What are the legal requirements for wet separators?

The operation of wet separators in Germany is regulated by the 42nd Ordinance for the Implementation of the Federal Immission Control Act (42. BImSchV), which was issued in 2017. This was supplemented by guideline VDI 3679 of the VDI/DIN Commission. This legal situation results in a whole series of obligations for operators of wet separators with regard to the useful water for filtering in exhaust air operation.

Before commissioning a unit, an independent risk assessment including action plans must be carried out by a hygienically competent person if the limit values are exceeded.

  • The operator is obliged to keep a logbook with documentation of the samples.
  • Regular laboratory tests must be carried out, including verification.
  • A reference value for germ contamination must be established and adhered to.
  • The unit must be inspected at least every 5 years by an expert or an accredited inspection body.

Note: The 42nd BImSchV only applies to exhaust air operation. In principle, the water in recirculation mode should be tested regularly, as legionella can form in equal measure and endanger employees.

Wet separator cleaning, maintenance and disposal

Wet separators should be cleaned regularly, depending on the degree of contamination, in order to avoid deposits and to ensure constant separation performance. Various inspection openings and a cleaning set with hose are available for this purpose.

We recommend at least annual maintenance of your extraction systems in order to comply with product safety and operational safety regulations.

Wet separators use water as the main filter medium, and some products have additional filter stages. The contaminated process air is drawn through the exhaust system and filtered by water. In the process, light suspended matter and particles remain in the water, while coarser particles sink to the bottom and are disposed of as so-called sludge discharge. The less residual water there is in the discharge, the less expensive it is to dispose of. Our sludge tanks therefore contain a sieve together with filter fleece, which separate the water from the sludge.

When does wet dust removal make more sense than dry dust removal?

Numerous parameters must be taken into account for the selection of the ideal dust removal system. Whether a wet separator or dry separator can be used depends on the following factors, among others:

  • Material composition and quantity of the extracted medium
  • Carcinogenic, flammable or explosive substances
  • Daily operating time/shift operation
  • Sparks
  • Flammable or explosive dusts
  • Required air volume and extraction power
  • Energy consumption and operating costs
  • Capture and discharge system

Depending on the manufacturer and product, the filter medium in wet separators consists of a water basin or water vortex and further filter stages. The cost of replacement filters is partially eliminated by using water, but disposal of the sludge is significantly more expensive than dry dust. When purchasing, care should be taken to use washable filter media, e.g. stainless steel mesh filters.


Explosion protection exhaust systems

Wet separators are particularly suitable for combustible and explosive dusts or processes with high levels of flying sparks, as here the filter medium water reduces possible fires or explosions in advance. Only a few manufacturers also produce ATEX dry dust extractors.


What are the wet separator techniques?

  • Wash tower / packed column
  • Jet scrubber (exhaust gas cleaning)
  • Vortex wet separator
  • Rotary wet separator
  • Venturi wet separator
  • Bypass channel scrubber

Our wet separator series B works with a specially developed channel bypass with innovative flow division, which is already patent pending. By dividing the air flow, wet separators from ABSAUGWERK consume significantly less energy and water, with 50% higher extraction power.

Wet separators from ABSAUGWERK

Every application is unique. Therefore, wet separators from ABSAUGWERK are available in various sizes and designs. With versatile options, we plan our extraction systems tailor-made and optimally adapted to your processes and materials. This way we can guarantee you an economical investment and deliver an effective extraction solution.

Explosion protection according to ATEX for wet separators

In the right mixing ratio with oxygen and an effective ignition source, flammable and explosive media in the form of gas, vapor, mist or dust can cause serious fires and violent explosions. This can injure people, destroy buildings and plant components, and ignite other flammable substances.

For this reason, so-called ATEX directives (ATmosphères EXplosibles) apply to industrial extraction systems.

Better for people and the environment









Clean air in production halls promotes the health of employees, makes workplaces safer and protects the environment. At the same time, machinery, tools and workpieces are protected and their service life is significantly extended.

When developing our wet separators, we paid special attention to low operating costs, high energy efficiency and low follow-up costs. For example, our metal mesh filters are easy to clean with a conventional high-pressure cleaner. In contrast to standard systems, our individual extraction systems consume only the amount of electricity, air and water that is actually needed. In addition, the cleaned air, which is still warm, can be returned to the hall through recirculation operation. This saves enormous energy costs, especially in winter.

Customized extraction systems for maximum efficiency and economy

The flexible unit components make it possible to configure customized extraction systems for almost any application. In this way, we ensure a positive impact on your energy balance and only consume the energy and resources that are actually necessary.

The ABSAUGWERK 360° Service

We accompany you from the first consultation through project planning to after-sales service as a reliable partner. Thanks to our many years of experience in extraction technology, we also have the expertise to convert and retrofit existing systems and also maintain extraction systems from other manufacturers.