What is the difference between an regenerative thermal oxidizer and an afterburner?

Regenerative Thermal Oxidizer (RTO): An RTO is an advanced air pollution control system used to treat and eliminate volatile organic compounds (VOCs), hazardous air pollutants (HAPs), and other harmful airborne contaminants emitted by industrial processes. The main objective of an RTO is to ensure compliance with environmental regulations and reduce the impact of industrial emissions on air quality.

An RTO typically consists of the following components:

1. Inlet Plenum: The exhaust gases from the industrial process are directed into the inlet plenum.
2. Heat Exchange Beds: The exhaust gases pass through heat exchange beds filled with ceramic media. These beds alternate between the incoming and outgoing gas flow paths, allowing for efficient heat transfer. The ceramic media retains and stores heat during one phase and releases it during the other phase, facilitating energy recovery.
3. Combustion Chamber: After leaving the heat exchange beds, the exhaust gases enter the combustion chamber. Here, a burner introduces fuel and fresh air to create a high-temperature environment.
4. Reaction and Destruction: In the combustion chamber, the high temperatures cause the volatile organic compounds and other pollutants to react with oxygen, resulting in their oxidation and conversion to carbon dioxide and water vapor. This combustion process ensures the complete destruction of the pollutants.
5. Outlet Plenum: The purified gases exit the combustion chamber and pass through the outlet plenum.
6. Stack: Finally, the treated gases are released into the atmosphere through a stack or chimney.

The heat exchange beds in an RTO play a crucial role in energy efficiency. They capture and transfer heat from the hot exhaust gases to the incoming untreated gases, preheating them before they enter the combustion chamber. This heat recovery reduces the energy required for the oxidation process and improves the overall thermal efficiency of the system.

Afterburner: An afterburner is a combustion device primarily used in certain jet engines, typically found in military aircraft. Its purpose is to provide an additional burst of thrust when required, such as during takeoff, combat situations, or high-speed flight.

The afterburner is positioned downstream of the main combustion chamber in the engine. When activated, it introduces additional fuel into the exhaust stream, which is ignited and rapidly burned. This combustion process occurs in the afterburner's combustion chamber.

The introduction of extra fuel and subsequent combustion in the afterburner results in a significant increase in the exhaust gas temperature and velocity. The higher gas velocity provides a boost in thrust, effectively augmenting the engine's power output. This temporary increase in thrust can enhance the aircraft's acceleration, speed, and maneuverability.

It's important to note that afterburners are fuel-intensive and have higher fuel consumption rates compared to non-afterburning engines. As a result, they are typically used selectively during specific operational phases where extra thrust is essential, while the engine operates in a more fuel-efficient mode during other phases of flight.

In summary, an RTO is an air pollution control system that treats and destroys pollutants emitted from industrial processes through a combustion process, while an afterburner is a device used in certain jet engines to increase thrust by burning additional fuel in the exhaust stream.