Thermally regenerative oxidation

In thermal regenerative oxidation, the heat exchange between the raw gas to be heated and the clean gas to be cooled takes place by means of an alternating flow storage mass consisting of ceramic bodies.

The size of the system is determined by the desired thermal efficiency, the pollutant load and the flue gas volume. Depending on the requirements, a system consists of at least two or more chambers.

With two chambers, it must be taken into account that when switching from one container to the other, there is a short circuit between the raw gas and the clean gas, which influences or worsens the clean gas value.

From a 3-chamber system upwards, the system can be equipped with a purge air device. The area below the storage bed is purged with air before it is released again so that clean gas can flow from the top to the bottom. The purge air expels the pollutants from the area under the storage mass and guides them into the combustion chamber. However, it is also possible to feed these into the raw gas, provided the fan is positioned on the inlet side upstream of the system.

The advantage over pure thermal combustion is that much higher thermal efficiencies can be achieved and therefore less primary energy in the form of gas or electrical energy needs to be supplied to the system.

In autothermal operation (i.e. the system no longer requires primary energy to maintain the oxidation temperature), excess energy can be conducted out of the combustion chamber by means of a hot bypass. This energy can be used in a secondary heat recovery system for further energy savings.