Natural gas, an essential resource for processes of European industries, is becoming increasingly scarce and expensive. With the uncertainty around gas availability and pricing, most companies are looking for alternative solutions to avoid excessive costs or production standstills.

Mobile activated carbon filters can be a viable substitute for air emission treatment. Air purification, one of the last production steps, is required by law in the European Union. This purification process is often done with regenerated thermal oxidizers (RTO) and it requires a consistent and high amount of natural gas. Replacing an RTO, even temporarily, with a mobile filter, reduces gas consumption while fully complying with emission regulations. Companies can then allocate the saved gas towards the core processes, where substitution with alternative technologies is not possible. Alternatively, the gas could also be stored to secure the company's gas supply, or be saved to reduce costs.

Thermal oxidation for air emission reduction

Thermal oxidation is a process used to destroy air emissions, such as VOCs or HAPs from industrial air flows. The pollutants are in general hydrocarbon-based and destroyed via thermal combustion, resulting in CO₂ and H₂O. In order to burn the pollutants in the stream, most oxidizers are operated at temperatures of more than 760 °C.

RTOs – one of the most widely used air pollution control technologies operate slightly different. They use a ceramic bed, which is heated from previous oxidation cycles to preheat the air stream and partially oxidize them. Then the preheated stream enters a combustion chamber, heated by an external fuel source to be fully oxidized. The target oxidation temperature of most RTOs ranges between 760° C and 820°C, in rare cases even going up to 1,100°C in order to achieve full destruction of the pollutants in the air stream.

Both processes require an external fuel source. Natural gas is the most widely used fuel source for thermal oxidizers. Additionally, these processes require nearly continuous upkeep of the operating temperature in order to work efficiently, which consumes large amounts of gas.

Activated carbon filtration for emission reduction

Activated carbon filtration is a proven technology for air emission reduction. Activated carbon is a non-hazardous carbon-bearing product with a porous structure and a very large internal surface area. Treatment of air emissions with activated carbon is based on adsorption, in which molecules adhere to an external or internal surface of a solid substance. Due to its very large internal surface area (up to 1,500 m²/g) activated carbon is ideal for adsorption.

Activated carbon filtration is efficient in removing pollutants such as VOCs or odorous components, such as H₂S or NH₃ from air streams.

Filtration with activated carbon functions autonomously, therefore it doesn’t require any external fuel, such as natural gas.

Mobile activated carbon filters as RTO replacement

While activated carbon filtration can be done with fixed filters, mobile activated carbon filters are the method of choice when it comes to (temporarily) replacing or optimizing an RTO, as it‘s a very adaptable and flexible solution. They are an already tested and approved technology for substituting an RTO, especially in case of planned maintenance, or to avoid a production standstill. 

DESOTEC is the leader in mobile activated carbon filtration and offers a unique 5-step-process:

Most companies are concerned about the uncertainty regarding the gas supply, especially for the upcoming winter. Therefore, it makes sense to consider every measure regarding reducing gas consumption. A mobile activated carbon filter can be a suitable alternative to RTO treatment for gas saving. To get an evaluation of your specific situation, get in touch with our experts.

Better be safe than sorry 

For some European countries, even a temporary change in a company’s air emission purification technology requires a change in its operating permit provided by the local authority. Many companies using an RTO for their emission treatment are already preparing themselves by adding alternative technologies, such as mobile activated carbon filters to their permit.

This precaution gives extra assurance that in case of RTO failure or maintenance, a mobile filter can be delivered and installed quickly, allowing the emissions to be still filtered from the airstream hence preventing unnecessary shutdowns or fines. Our team of Desotec experts can help you prepare for conversations related to permit adjustments.

To discuss how Desotec mobile filtration solutions could work for your company, contact our team today.

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