Thermal oxidizers are the simplest plants of the group of oxidizers: the air to be treated is sent to a combustion chamber where one or more burners keep it at a temperature of 720-950°C so that the pollutants are burned properly. This way the effluent is purified and sent to the stack and then into the atmosphere without any treatment. In this configuration, streams highly concentrated with pollutant, up to 50% of the LEL (Lower Explosion Limit) or nitrogen-inerted effluents, can be appropriately treated by means of, for example, blowing combustion air into the chamber. These machines are normally applied in the chemical, pharmaceutical, oil&gas and waste processing industries and can be equipped with all the pre-and post treatment systems making them useful for the intended purpose. They can be developed horizontally or vertically with the combustion chamber incorporating the exhaust stack.

Direct thermal oxidation unit features and advantages

  • Electrical switchgear with PLC and remote assistance.
  • Independent combustion system to guarantee correct operation of the plant.
  • Modulating combustion system to maintain the correct operating temperature with different incoming pollutant loads.
  • Combustion chamber refractory interior with high density ceramic fibre insulation, allowing the plant to last longer even with high concentration effluents or halogenated streams.
  • High purification efficiency > 99%.
  • Reduced size and weight.
  • Reduced production of secondary pollutants (CO, NOx).
  • Possibility of additional heat recovery.
  • Possibility of installing high temperature quencher and scrubber for application with acid fumes.

Thermal Oxidation Operating Priciple

The nature of this machine allows it to be adapted to various special applications with high concentration, injection in chamber and incineration, and therefore it is not easy to provide it with a standard description. The polluted air is burned inside the combustion chamber. The burner therefore has the task of heating the stream to temperature and burning the pollutants in it, while the combustion chamber contains the stream remaining at the correct temperature in order to destroy the pollutants. The combustion chamber must therefore be sized considering the speed, temperature, turbulence, permanence time and flame development volume parameters. The effluent will leave the chamber of the direct oxidizer at the chamber temperature and this heat can be used as deemed most appropriate with the aid of heat recovery units. A temperature measuring system, assisted by a panel with PLC, maintains plant management within functional conditions, without requiring personnel with complex training.

Thermal Combustor plant engineering and solution

  • Heat recovery downstream of the combustion chamber thanks to our energy recovery solutions.
  • Quencher made with special alloys for corrosive gases.
  • Scrubber for corrosive gas abatement.
  • Low emission NOx burners and/or deNOx SCR (Selective Catalytic Reduction) systems.
  • Turnkey supply.
  • Complex stream injection into the chamber.

Thermal oxidizers with pre/post treatment

Plants designed by integrating pre-and post abatement sections to the main oxidizer are used when complex pollutant streams need to be treated with several different technologies.

The pre-treatments and therefore the pre-scrubbers are used to preserve the thermal oxidizer both from a mechanical and process point of view, reducing the concentration of particular types of pollutants such as:

organic silicone compounds
inorganic acids
inorganic bases
painting overspray
oily mist and/or condensate droplets

In this condition, appropriate systems are installed, such as cyclones, bag or cartridge filters, Venturi and tower scrubbers, filtering panels, activated carbon adsorbers, various types of demisters or even more complex systems to evaluate for each case.

For post-treatments and therefore for the post-scrubbers, rapid cooling systems are typically used such as quenchers followed by tower scrubbers possibly with Venturi-pre-abatement.

At times DeNOx SCR or SNCR systems could need to be used to reduce NOx consisting of particular organic compounds such as amines.

The various post-abatement systems are applied in the presence of incoming pollutants such as:

Halogenated VOC
Sulphurised VOC
Nitrogenous VOC
Silanes or siloxanes

Services provided

Choosing Brofind means:

  • Customer assistance 24/7
  • Impartiality in recommending pollution control technologies since Brofind is owner of many of them
  • Experience in the design and manufacturing of abatement plants since 1993

See the page dedicated to Brofind services to understand how we support our customers during the entire lifecycle of the product.