2^nd GUIDE Europe case study: DSI’s automated ammonia plate for the fish processing plant in Lithuania

Espersen is a world leading fish processing company with production plants in Denmark, Poland, Lithuania and China. In Klaipeda, Lithuania, Espersen Lietuva UAB is operating one of the most modern fish processing plants in Europe, where fish products are being prepared and frozen for customers in Europe and the United States. Products are white fish species that are prepared as frozen blocks, frozen fillets and breaded products. 
 

Tailor made automated ammonia plate freezing system results in faster handling of fishes
 

Espersen were looking at upgrading their freezer capacity with an automated plate freezing system to freeze white fish fillets in consumer packs. The previous handling was mainly manual and a high degree of manual labor was required to handle the product into and out of the standard horizontal plate freezers. There was also an expectation that the drip loss from the product could be reduced, as a result of faster handling of the product into the freezer with an automated system.

About the ammonia system

The freezer is designed with the aim of getting cooling contact to the product as fast as possible. The freezer operates on an ammonia system with pump circulation with an evaporation temperature of -40°C. The DSI horizontal single station opening freezer only opens one station at a time for loading and unloading. The result is that as soon as the product is packed it is conveyed into the freezer and loaded into the freezing station. The station is closed and there is double contact to the cold freezer plates. The HS Inline Horizontal Plate Freezer type HKS 36/20 is designed to freeze 750 kg of consumer packed fish fillet products. Product enters at +5°C and is frozen to -18°C in less than 80 minutes.

Fast freezing contributes to low operation costs 

The continuous loading of the freezer results in a stable refrigeration load compared to standard batch load freezing, where the refrigeration load varies from a very high load initially to a very low load when the product is frozen. This means that the overall energy efficiency is improved.
 

The product quality is improved due to the fast transfer of the product to the cold plates of the freezer. On top of this the drip loss of the product is reduced, also contributing to the overall economy of freezing in a continuous production flow.
 

The performance of the freezer is actually better than expected, which is why Espersen has taken some of the stations of the freezer out of operation, making it possible to increase production if there is need.

About DSI

DSI is a leading company involved in designing and manufacturing manually operated and automatic plate freezers. DSI manufactures many different types of manual horizontal and vertical plate freezers, which are suitable for use in onshore and marine installations.