QCT Quick Chill Tunnel

At a Glance

  • Cooling capacity 750 pig carcasses per hour
  • Cooling time <2 hours
  • Tunnel cooling capacity approximately 2.9 MW at -35°C
  • Secondary propylene glycol loop for medium temperature services
  • Stainless steel refrigerant pipelines
  • Desiccant dehumidifier at tunnel inlet for infiltration minimization
  • Tunnel air temperatures from -24 to -12°C.

This liquid overfeed ammonia refrigeration system services a quick chill tunnel for a new SKBF kill floor at Kingaroy, Queensland. This is the largest quick chill tunnel for pigs in the southern hemisphere.

The plant is designed as a dual compression stage, three temperature ammonia refrigeration system with two dedicated low-temperature booster compressor packages, one low low-temperature screw compressor package and one-second stage compressor package all located within the QCT engine room. The low low-temperature compressor services the in-line Advantec offal freezer.

In addition to these four machines, a fifth new screw compressor package was installed within the existing CEP engine room that services the new Boning Room among other things. The new compressor in the CEP engine room is identical to the existing three screw compressors in that plant room.

The QCT tunnel is cooled by thirty-seven (37) special induced draught evaporators each arranged for automatic hot gas defrost and each fitted with air intake hoods, directional fan plenum chamber and automatic valve station. To remove a large amount of frost accumulating on the evaporators during chilling, these are provided with relatively wide and staggered fin spacing. In addition, the fully automated defrost process is sequential with defrost parameters to suit individual evaporators and their respective positions within the tunnel.

The QCT is divided into five temperature zones for minimization of chilling weight loss and minimization of bacteria growth potential on the carcass surfaces. Following a retention period of less than two hours within the QCT, the heat removal from the carcasses is essentially complete. The product is then automatically transported to a number of equalizing rooms where carcass temperatures are equalized in preparation for boning and further processing.

Scantec, are experts in refrigeration design, installation and servicing. To enquire about a refrigeration plant design for a new site or for a retrofit click here to contact us today or call 07 3890 9400.