Groundbreaking decanter

Alfa Laval’s new decanter cuts power consumption by 40 percent while improving performance.

DATE 2023-11-28

The aldec G3 decanter, Alfa Laval’s third-generation decanter, is nothing less than a revolution in the world of wastewater treatment, cutting power consumption by up to 40 percent while improving performance on cake dryness. It targets municipal wastewater treatment plants primarily but is also aimed at industrial wastewater treatment plants.

“For the first time in history, it might actually be worth replacing an old decanter with a new one before the old one is completely worn out,” says Bent Madsen, manager, Process & Technology, Product Centre Decanters at Alfa Laval. Madsen has worked on the development of the Alfa Laval Aldec G3. “It is quite unique that the investment in a new decanter pays off before the lifetime of the old decanter is up.”

Two new features make this possible – the Alfa Laval Power Plates and the Alfa Laval Slimline design. The Power Plates reduce the loss of kinetic energy when the liquid leaves the bowl, reducing flow-related power consumption by up to 20 percent. The Slimline design features a smaller conveyor diameter, which means there is room for more liquid in the pond, and the pressure on the bowl wall can be higher. This paves the way to either a drier cake or less use of polymer. The smaller discharge radius can save an additional 20 percent in power costs, and a drier cake helps solids handling and saves on transport costs.

“This is a product for customers who focus on their operational costs,” says Brian Munch, business manager, Environment Technology at Alfa Laval. “Sometimes it’s just a matter of making a simple calculation to know the actual impact on the operational costs.”

The development of the Aldec G3 began some years back. Alfa Laval determined to develop an extraordinary product that would really make a difference, focusing on both reducing power consumption and improving performance. “The large power consumption of decanters actually disturbs the separation process, so we figured if we could reduce power consumption we would improve the result as well,” explains Madsen.

The final solution featuring the Power Plates and the Slimline design is actually quite simple – so simple in fact that the Alfa Laval Aldec G3 is often met with initial scepticism. When it was launched at a municipal wastewater exhibition in Munich, Germany, in September 2010, the customers invited to the launch couldn’t believe that such a simple solution could make such a difference. “They first wondered ‘Can that really be true?’” says Munch. “We have been facing a challenge of how slim we could make the conveyor design without loosing its stiffness. But we have found a new way of doing this.”

The results speak for themselves. The Alfa Laval Aldec G3 has been tested in full scale at a wastewater treatment plant in Chicago, in the United States, with great results. And the first customers to buy and install the Aldec G3 have already seen the promised results.

Talk to an expert



municipal wastewater ontario

In Central Canada
Marc Hunt, Technical Sales Manager
+1 888 253 2226
, Ext. 3421
Email Marc

Brian Kelly Municipal Maintainance

Brian Kelly, Service and Parts
+1 888 253 2226, Ext. 6342
Email Brian


In Quebec
Pierre Gosselin, Technical Sales, Service
Pierre Gosselin +1 450 466 0555 
Email Pierre



Joshua Kowalchuk, Technical Sales, Service
Call: +1 587 643 5505
Email: Josh



Talk to Canadian Experts


+1 888 253 2226 
Expert Canada Brewery equipmentAlfa Laval's Canadian Expert in
Brewery Technology/Equipment, is Martin Ivanov, P.Eng. Ext. 343

Email Martin a question at

British Columbia
Derek GluschenkoDerek Gluschenko, Technical Sales Service
+1 604 734 2225
Email Derek 



  • Lower power consumption (which also greatly reduces CO2 emissions)
  • 10% boost in processing capacity – or drier cake
  • Reductions in life cycle costs
  • More efficient bio-solids handling
  • Better process monitoring and control 

Customer's voice

We have recently tested the Alfa Laval ALDEC G3 decanter in our wastewater treatment plants in Klingnau, Killwangen and Neuenburg. The results from the first evaluations are good, although they are still to be verified. We could see a clear improvement in energy efficiency, while cake dryness is slightly higher and the decanter reliability is on par with the previous model. It is, however, too early to conclude anything regarding the use of polymer. “Overall it can be established that Alfa Laval, with its new generation of decanters, has taken yet another step into the future of  wastewater treatment.

Josef Brem, owner, Brem ArA Dienstleistungen Ag