There are two practicable ways of oxidizing or burnout systems. On the one hand there are purely oxidation and on the other hand catalytic units.
On the oxidation side there are again two processes: thermal and thermal regenerative processes. At the beginning of developing thermal regenerative systems these were meant to be implemented whenever volume flows were high and concentration levels low. This principle, however, has long been abandoned and there is hardly any application today where the thermal regenerative alternative does not predominate over the purely thermal one. The advantage of regenerative processes as compared to the recuperative ones is that the unit can reach auto-thermal operating level with low loads - depending on pollutant concentration (no primary energy needed to keep combustion temperature level) - and at the same time the surplus of energy for higher concentration levels can be separated to be used for other heating purposes.
Catalytic processes are used where (depending on the process) no catalytic converter toxics have to be taken into account now and for future developments. A clear advantage is that the process of oxidizing pollutants on a catalytic converter takes place at low temperatures. This significantly influences the size of these kinds of units.