Technology
The waste gas from the process tool is fed into the center of a burner, and thermal decomposition of the waste gases occurs in the flame.
Depending on the chemical composition of the waste gases, various reactions take place (oxidation, reduction, pyrolysis).
In the subsequent scrubbing process, the gaseous and solid compounds generated in the burning process are bound by a suitable liquid.
When abating waste products sensitive to hydrolysis or oxidation, the Nitrogen-Purge-System (NPS) is installed and lines and valves are heated. Typical examples are Boron Trichloride, Tungsten Hexafluoride and Silane, which react with airborne humidity or oxygen and form deposits, which can cause clogging in lines and fittings.
Combustion Chamber
A special burner- and combustion chamber design is utilized in the ESCAPEINLINE® for a more efficient combustion. The combustion chamber with integrated burner is made of corrosion resistant high tech materials. A dome prevents any scrubbing liquid from entering the combustion area. The reactor area is dismantled without tools and can be easily cleaned. Depending on the customer’s abatement requirements, DAS offers several reactor options (ceramic or metal chambers).
The flame is detecteded by two independent UV sensors. The pressure in the burning chamber is monitored by an analog pressure sensor.
The abatement of waste gases from more than one process chamber poses problems when the mixture of effluents carries high risk of adverse reactions. Those reactions are eliminated with the multi-inlet burner design developed by DAS GmbH, Dresden. Waste gases of up to four process chambers are led into the burner with four separate inlets. They are not mixed until they reach the flame. At this point their controlled reaction is safe.
Scrubbing and Lye Recirculation System
The ESCAPEINLINE® recirculating flow has been increased for a higher absorbtion and a more efficient cooling of gases. The scrubber absorbs particles and the acidic gases with a recirculating alkaline liquid. The liquid is pumped from a tank and sprayed above the burning chamber and the scrubber.
Simultaneously, hot gases from the combustion areas are cooled down. Scrubbed gases exit the system via a demistor into the main exhaust line. All components of the recirculation system are made of corrosion resistant materials. The automated recirculation system controls flow rate and the pH of the scrubbing liquid.
In the storage tank, a defined mixture of water and lye is prepared using level sensors and a metering pump. Concentration of lye is varied by adjusting the metering pump settings. A corrosion-resistant centrifugal pump delivers and disperses the scrubbing liquid through flow meters and spray nozzles
Leak protection is provided by double containment, the outer tank has the capacity to hold all of the liquid from the inner tank.
