Kjeldahl scrubber - Scrubber K-415

Key technical specifications

• Compatible instruments: BUCHI KjelDigester and SpeedDigester 
• Available configurations: OneScrub, DuoScrub, TripleScrub, TripleScrubECO and QuadScrubECO 
• Filtration / cleaning steps: neutralization and adsorption; optional condensation; optional reaction step depending on configuration 
• Neutralization vessel capacity: 3 L 
• Cooling water control: included with TripleScrubECO and QuadScrubECO 

The BUCHI Scrubber K-415 is a laboratory fume treatment system for BUCHI digestion instruments. It is designed to draw off aggressive acid or alkaline fumes and treat them through a configurable sequence of cleaning stages, helping reduce the release of harmful vapours during digestion work.

Depending on the selected configuration, the system can combine neutralization, adsorption, condensation and a reaction step. This makes it suitable for standard digestion workflows as well as applications requiring more advanced fume treatment, such as processes involving specific redox reactions.

Model comparison

The Scrubber K-415 is available in five configurations. All models include neutralization and adsorption; higher configurations add condensation, ECO cooling water control and, in the QuadScrubECO version, a reaction step.

• OneScrub
  Basic two-stage version for SpeedDigester.
  Neutralization + adsorption; 21 L/min pump suction capacity; up to 12 sample tubes. 
• DuoScrub
  Standard two-stage configuration.
  Neutralization + adsorption; 32 L/min pump suction capacity; up to 20 sample tubes. 
• TripleScrub
  Three-stage configuration with pre-condensation.
  Condensation + neutralization + adsorption; 32 L/min; up to 20 sample tubes. 
• TripleScrubECO
  Three-stage ECO configuration with water control.
  Condensation + neutralization + adsorption; automatic cooling water control; digester control; 32 L/min; up to 20 sample tubes. 
• QuadScrubECO
  Four-stage ECO configuration for advanced fume treatment.
  Condensation + neutralization + adsorption + reaction; automatic cooling water control; digester control; 32 L/min; up to 20 sample tubes. 

Up to four cleaning stages

The K-415 is built around a staged fume treatment concept. In the most complete configuration, fumes first pass through a condensation stage, then a neutralization vessel, followed by adsorption and finally a reaction stage. According to the technical data sheet, the condensation step pre-condenses fumes to avoid dilution of the second stage; the neutralization stage treats the output from condensation; the adsorption stage collects particles of organic and inorganic substances; and the reaction stage is intended for specific reactions such as reduction or oxidation, including aqua regia digestion. 

Neutralization and adsorption as the core configuration

All K-415 configurations include neutralization and adsorption. This makes these two stages the functional basis of the system. The neutralization vessel has a 3 L capacity, while the adsorption stage uses activated charcoal to retain particles and support aerosol recondensation. 

Condensation for workflows with higher condensate load

TripleScrub, TripleScrubECO and QuadScrubECO add a condensation stage before neutralization. This is useful where fumes should be pre-condensed before entering the neutralization vessel, helping prevent dilution of the following stage. 

ECO versions with automatic cooling water control

TripleScrubECO and QuadScrubECO include cooling water control. The ECO models use an automatic cooling water valve so that only the required amount of tap water is used. In addition, the ECO models include the connection cable that allows the scrubber to be controlled via the connected digester. 

Reaction step for demanding fume treatment

QuadScrubECO adds the fourth cleaning stage: the reaction vessel. The technical data sheet describes this stage as intended for specific reactions such as reduction or oxidation, with aqua regia digestion given as an example. This makes QuadScrubECO the relevant configuration when the workflow requires this additional reaction-based treatment step. 

Additional technical data

• Cleaning stages in the full configuration: condensation, neutralization, adsorption and reaction
• Pump suction capacity: 21 L/min for OneScrub; 32 L/min for DuoScrub, TripleScrub, TripleScrubECO and QuadScrubECO 
• Adjustable system suction capacity: 15 mbar for OneScrub; 50–400 mbar for other K-415 models 
• Maximum number of sample tubes in connected digester: 12 for OneScrub with SpeedDigester; 20 for other models 
• Connection voltage: 100–230 VAC ±10 %, 50/60 Hz 
• Power consumption: 180 W for OneScrub; 140 W for other models 
• Dimensions: from 248 × 412 × 526 mm to 347 × 450 × 543 mm, depending on model 
• Weight: 8.9–12.9 kg, depending on model 

Which model to choose

OneScrub
A simple neutralization and adsorption configuration for use with SpeedDigester, with a maximum of 12 sample tubes.

DuoScrub
A standard two-stage configuration for workflows requiring neutralization and adsorption, with higher pump suction capacity than OneScrub and support for up to 20 sample tubes.

TripleScrub
Suitable when condensation is required before neutralization, but automatic cooling water control and digester-controlled scrubber operation are not needed.

TripleScrubECO
Suitable when condensation is required and the user also wants automatic cooling water control and scrubber control via the connected digester.

QuadScrubECO
The most complete configuration, adding a reaction stage to condensation, neutralization and adsorption. It is the relevant choice for workflows requiring specific reduction or oxidation reactions, including aqua regia digestion.

Applications

The Scrubber K-415 is used wherever digestion processes generate acid or alkaline fumes that need to be removed and treated before release.

• Nitrogen and protein analysis by Kjeldahl digestion — for digestion workflows used in food, feed, dairy and agricultural sample analysis. 
• Fume treatment for BUCHI digestion systems — for KjelDigester and SpeedDigester workflows where acid or alkaline fumes are generated during sample digestion. 
• Aqua regia digestion — for demanding digestion workflows requiring an additional reaction step, for example reduction or oxidation of specific fumes. 
• TKN workflows — for Total Kjeldahl Nitrogen workflows where condensate collection and draining accessories are relevant.