Downcomer Duct

Plant protective pre-cooling

As an alternative or addition to the gas cooling tower, the gas can also be cooled down after the preheating tower in the downcomer duct. This option is often used in new plants and plants with a long and straight duct. In the case of existing plants, injection into the downcomer duct is performed to optimize the process (e.g. to increase production or when using alternative fuels). In this way, temperature peaks can be compensated and where necessary, subsequent cooling in the gas cooling tower supported. Due to the associated reduction in the operating gas flow rate, there is an energy savings potential at the downstream fan.

Downcomer Duct

Our solution

Regarding the downcomer duct, similar factors need to be taken into account as with the gas cooling tower. Owing to the smaller cross-sections and the higher velocity that results, the evaporation time is reduced compared to the gas cooling tower. The required outlet temperature and the available evaporation distance determine the amount of water required and the droplet size necessary for complete evaporation.

Complete evaporation is required to prevent material build-up and to ensure the durability of the downstream fan. Due to the higher gas velocity and the resulting decrease in evaporation time, finer droplets are required. This is why almost exclusively twin-fluid systems are used. In order to provide the perfect solution, we configure the systems according to your process data and duct dimensions.

Corresponding products

Düsenlanzen und Systeme für die Gaskühlung

Nozzle lances and systems for gas cooling

Efficient cooling and conditioning

Lechler nozzle lances and systems to generate the optimum droplet size range and distribute it as uniformly as possible in the gas flow.

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Lechler Air Quality Control Systems (AQCS)Phone +49 (0)7123 962 0Fax +49 (0)7123 962 301env(at)

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