RTO Afterburner for Combustion Engines: CO and VOC Abatement
High-efficiency regenerative thermal oxidation for cogeneration plants
LAI Srl has designed and developed a regenerative thermal oxidizer (RTO) for internal combustion engines, an advanced solution for certified abatement of carbon monoxide (CO), total organic compounds (TOC) and volatile organic compounds (VOCs) in exhaust gases from cogeneration units.
The system was developed in-house by LAI’s technical department in response to increasingly stringent air-emissions regulations. Cogeneration plants subject to an Integrated Environmental Authorization (AIA) or specific limits imposed by regional permits must demonstrate compliance with ever tighter emissions limits, which engines alone cannot meet without an exhaust after-treatment system.
The system works on the principle of regenerative thermal oxidation: engine exhaust gases are fed into a thermally insulated combustion chamber, where they are brought to an operating temperature of 800–950 °C, high enough to convert almost all organic residues and CO into carbon dioxide and water vapor.
The heat generated by the process is recovered using two ceramic chambers that alternate between storing and releasing thermal energy. This regenerative configuration allows the system to reach thermal self-sustaining operation after the first few hours of start-up, reducing auxiliary fuel consumption to zero—or close to it—during steady-state operation. Start-up is provided by electric preheating elements, which bring the ceramic media to operating temperature in 2–3 hours before the engine exhaust gas enters the system.
The LAI afterburner is fully managed by a PLC with remote control, continuously monitoring the temperatures in the ceramic chambers, differential pressure, incoming gas parameters and automatic valve switching sequences. No manual intervention is required during normal operation: the system starts up, reaches operating temperature and manages oxidation autonomously, sending alerts if anomalies occur and adjusting the valve switching cycle to optimize thermal efficiency.
In addition to biogas and natural-gas cogeneration applications, the LAI afterburner is suitable for treating off-gases from biogas-to-biomethane upgrading plants, as well as emissions from industrial processes such as painting, plastic lamination and other operations that generate significant VOC emissions. It can be installed in new plants or retrofitted to existing systems, with mechanical and electrical connections adapted to the host plant.
