Thermally regenerative oxidation

Thermal regenerative oxidation consists of 2 or more chambers. The number of chambers required depends on the exhaust gas volume flow, the pollutant load of hydrocarbons, the thermal efficiency and, in some cases, the pressure loss of the system permitted by the customer.

The raw and clean gas duct is located at the bottom of the systems, which in turn is attached to the cone with the changeover dampers. The heat storage bed begins above the cone, at the end of which the oxidation chamber begins.

The heating device is mounted in the oxidation chamber itself, which is realized either by a burner system or by electric heating. Oxidation takes place between 720 and 850 °C and the maximum combustion chamber temperature is 1,100 °C.

Normally, the design attempts to achieve autothermal operation of the system by means of the storage mass and the pollutants in the flue gas, in which no additional energy in the form of gas or electrical energy is required to maintain the oxidation temperature.

In 3-chamber and multi-chamber systems, a purging air device is installed to purge the container charged with raw gas using clean gas before the clean gas is fed through it into the clean gas line. The purging process displaces the remaining raw gas pollutants from the cone area, which would otherwise impair the clean gas value. The design of the purge air system depends on whether the system fan is installed upstream or downstream of the system.

If the system reaches the over-autothermal state, it is possible to install a hot bypass. This is used to feed hot clean gas from the combustion chamber directly into the clean gas downstream of the system. This also allows higher exothermicity due to the flue gas pollutants in the system to be purified.

If there is excess energy or hot clean gas, a secondary heat recovery system can be installed to save even more energy.