Treatment of LED and GaN Industry Waste Gases with LARCH

The LARCH burner system has been especially designed by DAS Environmental Experts for the point-of-use treatment of waste gases from MOCVD processes in the LED industry. It is capable of treating large flows of hydrogen and ammonia as well as small flows of metal-organics and dopants.

Waste Gas Treatment – LARCH

Treatment of Waste Gases with Burner Technology

The treatment combination of oxidation and pyrolysis extends DAS´ technology portfolio in a sustainable way. Low investment and operating costs, a simple, robust design and low environmental impact (no CO2 emissions, minimum NOx emission) characterize LARCH. Current installations demonstrate maintenance intervals of more than six months. Maintenance access is possible from t sides. Operation costs can be optimized with a process tool interface. By the application of heat exchangers, the process gas heat can be used for other production areas.

LARCH Operating Principle

The system operates in three steps. Firstly, the process waste gases are introduced through a special packed inlet into the decomposition zone. There, decomposition of Ammonia takes place. Subsequently, the Hydrogen is electrically ignited and oxidized. The waste gases are burned and oxidized within the reactor. Finally, the waste gases are cooled in a heat exchanger. They can be released into the environment without any further treatment as they meet the strict German standards for air pollution (TA Luft). 

Operation Principal LARCH

Your Advantages

  • No CO2 emissions: no greenhouse gases, low NOx emissions
  • No Wastewater: no trouble with NH4+ wastewater limits
  • Treatment of H2 at the Point-of-Use: Maximum Security regarding H2

Technical Data

  • Dimensions (W x D x H): 1350 mm x 1000 mm x 2000 mm
  • Access to maintenance area on front and back side
  • Gas entry: DN40
  • Gas outlet: DN300 (standard)


The following equipment options are available for all LARCH systems:

  • Power Supply: 3 x 400 V/50 Hz or 3 x 208 V/60 Hz
  • Process Tool Interface
  • Signal Tower
  • Drip Pan
  • Earthquake Safety Kit
  • Two cooling concepts available
  • Internal pressure regulation by controlled damper or fan with frequency converter