Alfa Laval’s Economiser Unit For EGR System- A Great Fuel Saver



Alfa Laval is a leading global provider of specialized products and engineering solutions based on its key technologies of heat transfer, separation and fluid handling.

Alfa Laval has introduced an “economiser” version of its exhaust gas recirculation (EGR) system.  This system paves the way for extraordinary energy and fuel savings.

The Technology explained:  

Diverted heat:

Aalborg EGR-HPE that is placed in-line before the EGR pre-scrubber spray jets that cool the exhaust gas, the economizer has access to much higher temperatures than traditional exhaust gas boilers.  So while the installation is light, compact and self-cleaning takes place due to the high speed of gas flow, its application potential is enormous as it increases the efficiency of a conventional waste heat recovery system.

Steam Turbine: 

With the output of the traditional economizer feeding into the shared drum, the Aalborg EGR-HPE produces extremely high-quality steam with a temperature of just above 400°C, bringing the waste heat recovery system to a much higher level of efficiency.

Fuel savings: 

Aalborg EGR-HPE in an integrated system allows waste heat recovery to occur at lower main engine loads than would be possible with a traditional waste heat recovery system in Tier III operation.  It allows for the possibility of even slower steaming with huge fuel savings.

John Pedersen, business manager for boilers, combustion and heaters at Alfa Laval, is quoted to have said: “The EGR economiser makes waste heat recovery beneficial at far lower engine loads, down to around 30%, this means that vessels can steam even slower, with huge fuel savings as a result.”

The unit underwent rigorous testing onboard the Maersk Cardiff.  This was a project supported by the Danish Energy-Technological Development and Demonstration Programme (EUDP) and developed in cooperation with Aalborg University.

Ole Christensen, Senior Machinery Specialist at A.P. Moller-Maersk, based on the test results aboard Cardiff, commented about the physical realities of EGR: “ The temperatures are twice as high as those of traditional waste heat recovery and the gas pressures are far greater.  Not only did the boiler survive, the results we have seen during testing are very promising.”

Source: Alfa Laval