Lean air unit from LT GASETECHNIK

600 400 Alexander Hanf

Area of application

LT lean air units are often used in the chemical industry. In chemical processes, e.g. in the production of synthetic resins or lacquers, lean air is used to supply solvent boilers and reactors. The normal oxygen content in air (which is about 20.95 Vol.%) is to be reduced to a defined proportion (usually 4 to 10% Oxygen in mixed gas). For this purpose, technical air (compressed air) is mixed with nitrogen (N2), so that lean air with a defined Oxygen (O2) concentration is generated.

Why should you use a Lean Air Unit from LT GASETECHNIK?

Keeping the specified oxygen content on the defined level has an influence on the quality of the production process and furthermore has safety reasons. Lean air is often used in a potentially explosive atmosphere. If the maximum permissible oxygen concentration is exceeded, this can lead to detonation and, as a result, to serious accidents For producinglean air in hazardous area appropriate regulations must be ob-served and adapted components must be used.

Depending on customer specification, LT GASETECHNIK lean air systems are equipped with a gas analyzer (partly also compliant with the safety integrity level SIL 1 or SIL 2), which measures the O2 concentration in the mixed gas. The mixing result is thus permanently monitored and optimized; In addition, the control can safely prevent inadmissible oxygen concentrations.

LT GASETECHNIK has more than 45 years of global experience in gas mixing plants. With us you are on the safe side!

Equipment variants

LT Lean Air Units are always designed according to customer specifications and are equipped accordingly. The following equipment variants are common:

  • Design of the unit for a hazardous area or for non-hazardous area
  • Gas filter on the gas inlet (police filter)
  • Pressure control of compressed Air and Nitrogen on the same mixing pres-sure
  • Measurement of the volume flow (temperature- and pressure-compensated)
  • Nitrogen bypass
  • Pressure controlled and/or volume-flow controlled
  • Storage of the mixed gas in a buffer tank, e. g. if the demand quantity varies
  • Designed for continuous or discontinuous demand
  • Autonomous system with local touch-screen control panel and bi-directional connection to a higher-level process control system
  • Gas analysis, also in SIL 1 or SIL 2 versions
  • Stainless steel version for aggressive environments
  • System for outdoor or indoor installation, in a steel cabinet or in a rack
  • Pressure holding valve, for vacuum


BASF Münster, Germany

  • Installation in ex-area
  • Capacity 40 cubic meters per hour
  • Inlet pressure:
    • Air 6 bar
    • N2 5 bar
  • Outlet pressure:
    • 5 delivery points
    • 0,5…1 bar and 1,5…2 bar
  • Buffer vessel with 500 litre
  • Controller and gas analyzer
    (in non ex-area)

DSM Meppen, Germany

  • Capacity 200 cubic meters per hour
  • Inlet pressure:
    • Air 6 bar
    • N2 5 bar
  • Outlet pressure: 3 bar
  • Buffer vessel with 90 litre
  • Nitrogen bypass
  • Controller and gas analyzer
    (signal transfer to the higher level process control system)

Synthopol Buxtehude, Germany

Two lean air units:

  • Capacity each 400 Nm³/h
  • Inlet pressure:
    • Air 6 bar
    • N2 5 bar
  • Outlet pressure: 3 bar
  • Buffer vessel with 3000 liter
  • Controller and gas analyzer
  • Outside errection
  • Control with gas analyzer, bus connection to the higher-level process control system for bidirectional exchange of all process data, alarm signals and fault messages

BASF Guadalajara, Spain

  • Installation in ex-area
  • Dynamic unit
  • Unit performance 250 Nm³/h
  • Inlet pressure:
    • Air 6 bar
    • N2 4 bar
  • Outlet pressure: 3.5 bar

Safe supply defined oxygen concentration in your process air.

This article as PDF: LTG-Magerluftanlagen-2017-01

Please contact us for your individual solution…