Air Products Uses New Technology to Build Revolutionary Tunnel Freezer

20-Jan-2003

Air Products announced the launch of the Freshline(TM) Z Tunnel Freezer, a new solution that, for the first time, combines cryogenic refrigeration, indirect heat transfer and impingement technology. The result, the company says, is a product that is setting new standards in terms of cost transparency, efficiency, operational safety, freezing quality and throughput-to-footprint ratio.

One of the major inefficiencies of today's conventional cryogenic freezing tunnels is that they use an exhaust fan to balance the system. Drawing too much gas out of the freezer results in wasted refrigerant and hence, higher operating costs. On the other hand, drawing too little gas can cause gas spills, which may lead to safety issues. To enhance safety, conventional freezing tunnels are designed to extract more gas. Consequently, they either sacrifice some efficiency or require frequent operator interventions.

The Freshline(TM) Z Tunnel Freezer overcomes these inefficiencies because it does not require an exhaust fan. Instead, the Freshline(TM) Z Tunnel Freezer has an indirect freezing system that uses liquid nitrogen to cool recirculating air rather than spraying it directly onto the product. Because the liquid nitrogen is in a closed system of heat exchangers and vents, spillage is eliminated and operator intervention is significantly reduced, while the refrigeration capacity of the liquid nitrogen is fully utilized.

The elimination of an exhaust fan in the Freshline(TM) Z Tunnel Freezer also results in a system that's easy to control and operate. The only parameters the operator controls are temperature and belt speed. Temperatures and heat transfer coefficients are stable both over time and across the belt of the Freshline(TM) Tunnel Freezer, which enables consistency of freezing and product quality for a wide range of food types including seafood, meat, poultry, and frozen meals.

The indirect freezing feature in the Freshline(TM) Z Tunnel Freezer is further enhanced by impingement heat transfer. This combination makes it possible to use the superior freezing power of liquid nitrogen even for sensitive foods like dough products. As a separate feature, Air Products offers real-time monitoring and logging of nitrogen consumption to help improve cost-to-product allocation and provide feedback on changes of control parameters.

https://www.chemeurope.com/en/news/19005/air-products-uses-new-technology-to-build-revolutionary-tunnel-freezer.html