EISENMANNThermal OxidationNew high efficiency heat exchanger concept

EISENMANN, the environmental tech-nology specialist based in Bblingen,Germany, introduces the new verticalthermal incinerator. This system promi-ses more output at lower investmentand operating costs. The externalappearance of this innovative systemclearly sets itself off from other thermal incinerator systems: The com-bustion chamber and heat exchangerunit are no longer arranged horizont-ally - as in traditional design - but vertically.

Thermal recuperative exhaust gaspurification systems used as down-stream processors for the disposal of volatile organic compounds fromsurface treatment have played anessential role in industry for a longtime. They typically work with tubularor plate heat exchangers for energyrecovery. Innovative heat exchangertubes are the basis for the system.These ensure high efficiency, since the crude gas flows through the tubeswith high turbulence. The higher efficiency reduces the heat exchangesection length by one-third, as comp-ared to the traditional design.

The flow optimization achieved in thisway is continued in the combustionchamber. There the hydrocarbons comeinto direct contact with the conicallyspreading flame of the burner, whichconverts them into carbon dioxide andwater vapor at temperatures around720 C. The oxidation process is con-trolled considerably better in compari-son with previous systems. Pre-ignitionis reduced by the guide vanes of theswirl burner, which mixes the crude gaswith the natural gas serving as primaryenergy. This reduces unwanted COgeneration at high solvent loading.

Thermal OxidationNow vertical instead of horizontalNew high efficiency heat exchanger concept

This also pays for itself in anotherway: Improved combustion is possiblewith lowercombustion chamber tempe-ratures and less fuel.

The compact design is a result from the skillful interplay between the swirlburner and the reduced length of theheat exchanger. Both elements make it possible to provide the thermal inci-nerator with a vertical arrangementinstead of its previous horizontaldesign. The advantages are obvious:Extreme thermal loading, which canlead to system collapse in combustionprocesses running uncontrolled, is nolonger possible. In view of the verti-cally arranged segments of the thermalincinerator, the material stresses resulting from thermal expansion aresignificantly minimized.

Maintenance and service of the newthermal incinerator offers a number ofattractive features. For example, boththe cold and the hot heat exchangersides can be cleaned conveniently. The system requires only 25 percent of the floor area of previous thermalincinerator systems, offering the plantplanning engineer more design possibi-lities in the layout. And one furtheradvantage: EISENMANN has provided an additional option for customers with special requirements, such as those in the graphite industry: thethermal self-cleaning of the thermalincinerator using the burn-out princi-ple via external heat exchangers withhot gas bypass.

The European environmental directive1999/13/EEC, better known as the VOC directive has become national lawand focuses intensely on the disposalof volatile hydrocarbons. The verticalthermal incinerator system newly deve-loped by EISENMANN takes up this current trend towards lower emissionvalues. It provides operators of produc-tion plants with solvent consumptionexceeding the threshold of five tonsper annum a highly efficient exhaustgas purification system with a smallerfootprint.

Purifiedgas

Bypass circuit forregulating theenergy balance

Crude gas

Swirl burner

Heat exchangertube bundle

Combustionspace

The new swirl burner ensures high turbulence of the crude gas flowing into the combustion chamber.

Inspectionbooth

EISENMANNEISENMANN Anlagenbau GmbH & Co. KG

Tuebinger Strasse 71032 Boeblingen Germany Phone +49 7031 78-0 Fax +49 7031 78-1000www.eisenmann.com info@eisenmann.com