298 94 307/02 Untersuchungen zum Stand der Umsetzung des ...

Teil 3 Seite 4-9
Load Shifting The Binary Ice plant runs normally at off-peak tariff or outside times with
otherwise high load).
Load Shaving is the most common operation of Binary Ice plants. The ice machine runs
over 24 h/d, enabling the smallest ice machine and storage volume
Applicability
Heat transfer and reduced weight loss
The properties of an ice crystal's rapid phase change with the resulting extreme
burn-off rate, are also responsible for the excellent heat transfer. The complete cov-
erage of ice crystals cools every spot of a warmer surface, and experimental results
show that air coolers yield significantly higher performance with Binary Ice than
evaporating refrigerant or brine [Ref 2]. Air coolers perform up to twice as well. This
means that the surface can either be reduced or the Binary Ice can be "warmer"
which results in lower energy demand and less – if at all – freezing of the surface.
Therefore the product weight loss is also smaller and defrost may even be unneces-
sary for air chillers. Liquid coolers can also be smaller (approx. 20 – 50 %).
Cooling "in situ" and cooling of packed food
The advantages of Binary Ice can also be extended to meat processors who are
becoming increasingly active in cooking processes (catering, convenience food etc).
Another process gaining in popularity is "sous vide" cooking. After cooking the food
is filled into plastic pouches (so-called "hot fill"). These pouches are then immersed
in Binary Ice and cool within minutes. Similar results are also achievable when im-
mersing other products such as fish in Binary Ice [Ref 3].
Economics
It is impractical in this format to give a complete detailed analysis of the economic ad-
vantages of Binary Ice installations. The following statements apply, however:
- Binary Ice plants are more economical the higher the peak cooling load compared to
the average cooling load. This is valid for any cooling demand and size of installa-
tion.
- Long pipe systems and numerous and varying cooling loads favour Binary Ice sys-
tems over any other direct or indirect cooling installation.
- Differences in peak and off-peak tariffs as well as sporadic availability of electric
power, favour Binary Ice systems due to cold energy storage (higher redundancy).
- The energy efficiency of generation of cold energy, transportation, storage and heat
transfer make Binary Ice systems superior to conventional refrigeration plants.
Driving Forces for Implementation in the Slaughterhouses