February 16, 2021

Geelen's Counterflow Recovery Unit saves energy and water use in aquafeed, food productions

Geelen Counterflow has developed the Counterflow Recovery Unit (CRU) which can help save energy and water use with its counterflow dryers and is used for extruded petfood, aquafeed and food productions.

"Two years of thermodynamic and computational flow dynamics (CFD) modelling have led to a prototype which was tested during eight months at a commercial production line," Geelen said, explaining the development of CRU.

CRU is a top-down, stainless steel vertical heat exchanger that recovers up to 75% of the energy and water from a counterflow dryer's exhaust air.

Dryers are the biggest energy consumers of any extrusion process, according to Geelen. Commonly, up to 60% of energy consumption at an extrusion plant is used to generate hot air to evaporate moisture from a product. After passing the product, the dryer's warm exhaust air (with its high relative humidity) transports moisture out of the dryer.

"It makes a lot of sense to recover the latent energy in that warm air through condensation before it is discharged. Condensing air will also significantly reduce the number of odor particles in the air," Geelen said.

Together with an electric heat pump and heat exchangers for drying air, CRU can eliminate the need for fossil fuels used for operations involving the drying of extruded petfood, aquafeed and food products.

This year, CRU will be installed in petfood and aquafeed plants in South Korea, China and Norway by Geelen clients that seek to eliminate carbon emissions in the next few decades.

- Geelen