Real all-rounders – RTO plants for low emission furniture production

Ecopure® RTO plant at
furniture manufacturer
Interlübke in Rheda-
Wiedenbrück, Germany.

Air pollution control through regenerative thermal oxidation (RTO) is highly efficient and suitable for almost all branches of industry. An Ecopure® RTO plant has been in operation at furniture manufacturer Interlübke’s Rheda-Wiedenbrück factory since March 2007.

With the new equipment Interlübke is assured not only of compliance with the statutory emission limits for volatile hydrocarbons, as defined in the 31st German VOC Directive (Bundes-Immissionsschutzverordnung or BImSchV), but also of efficient use of the heating energy generated.

Dürr supplied the RTO plant, complete with fan and pure gas exhaust stack and designed for the purification of a potential exhaust air volume of up to 110,000 Nm³/hr, as well as state of the art energy saving equipment. At Interlübke the concentration of 0.7 g/Nm³ of pollutant gases on entry to the RTO plant is comparatively low so additional fuel is needed to ensure an optimal combustion process.

The shortfall in energy supply is made up partly with natural gas fed direct into the exhaust air stream and partly by incorporating a multi-fuel burner capable of handling both liquid and gas fuels. The liquid solvents used in painting and cleaning processes at the German Rheda-Wiedenbrück factory are collected after use, distilled and then injected via atomizers straight into the RTO’s combustion chamber thus also providing energy for the incineration process. This reduces consumption of primary gas fuel whilst, at the same time, taking care of the disposal of liquid waste, for which charges are usually made. As a further energy saving measure both of the RTO’s gas burners are switched off once operating temperature has been reached and the need to heat up the air required for stoichiometrical combustion is eliminated. Electrical energy is saved by running the combustion fan at slower speed.

The plant at Interlübke is an example demonstrating that operating costs can be reduced by approx. 10% through intelligent energy management and the use of available resources – in this case liquid solvents. It also shows that even when, as for instance in the furniture manufacturing industry, low solvent coating systems are in use, the RTO process remains an effective and attractively priced method of air pollution control.

Your contact:

Werner Zondler - werner.zondler(at)durr.com