Gasåtergång

Gasåtergång is a Swedish term that literally translates to "gas return." It is often used in the context of industrial processes, particularly those involving the combustion of fuels or the operation of engines. The concept refers to the process where exhaust gases, or a portion thereof, are reintroduced into the combustion chamber or intake system.

In internal combustion engines, gasåtergång, commonly known as exhaust gas recirculation (EGR), serves several purposes. The primary benefit is the reduction of nitrogen oxide (NOx) emissions. When exhaust gases are recirculated, they mix with the incoming air-fuel mixture. These inert gases absorb heat during combustion, lowering the peak combustion temperatures. High temperatures are a key factor in the formation of NOx. By reducing these temperatures, EGR systems effectively decrease the amount of NOx produced.

Beyond emission control, EGR can also have an impact on fuel efficiency and engine performance. In some cases, recirculating exhaust gases can reduce pumping losses and improve the volumetric efficiency of the engine. However, excessive EGR can lead to a decrease in power output and potential issues like carbon buildup in the engine if not managed properly. The implementation and control of gasåtergång are typically managed by sophisticated electronic control units that monitor various engine parameters to optimize its effectiveness. The term can also be applied to other industrial processes where the recovery or repurposing of gaseous byproducts is involved.