Case studies

Project: Panda / Saudi Arabia


Planning / Implementation / Main components: Johnson Controls International
Refrigerant: Ammonia (NH3)
System start-up: 2008

The Saudi Arabian food retailer Panda Group of Companies built a state-of-the-art distribution centre in Riyadh that was put into operation in 2008. For this purpose Johnson Controls International implemented a central ammonia refrigerating plant.

Demands: The food retailer was interested in a central refrigeration design that had to be energy- and cost-efficient.
Solution:

The refrigeration needed for the different store rooms is generated centrally by three systems:

a) HT gravity circulation ammonia system using two T20-BWFG plate heat exchangers with three Frick screw compressors RXF68, 1,018 kW each, two on-duty and one stand-by producing 12 ºC; one chilled water facility for cooling the regular storage rooms

b) MT gravity circulation ammonia system using two T20-MWFG plate heat exchangers with 4 Frick screw compressors RWF II-134, 750 kW each, all on-duty producing chilled propylene Glycol at -10 ºC required for all MT applications

c) LT pump circulation system with two -36 ºC low-stage compressors RWF II-134 , 330 kW each, all on-duty with one swing compressor RWF II-134, 750/330 kW, for LT freezer room applications

7 banana ripening rooms connected with the MT glycol circuit, controlled by 110 propa controllers via central PC

2 forced-air wet coolers with -12 ºC pump circulation system connected with the MT system; serves to pre-cool all vegetables

All systems are controlled and monitored by a central PC unit using Johnson Controls DDC controllers FXO6, FX14, FX16. All coolers were assembled with variable-speed, built-in fan motors. I.e. the speed and temperature can be controlled to reduce power consumption and running costs.

Technical data:

 

Type of system Central ammonia refrigerating plant
Refrigerant: NH3
Refrigerant volume 500,000 m³ in the HT areas at 12 ºC, 60,000 m³ in the MT areas at different medium temperatures, 22,000 m ³ in the LT freezer rooms
Secondary refrigerant

Water, glycol

Refrigerating capacity

HT = 2,036 kW at 12 ºC, MT = 3,000 kW at -13 ºC, LT = 660 kW at -36 ºC

Main components Screw compressors by Frick, module-welded plate heat exchangers by Alfa Laval, evaporative condenser by BAC, evaporators and air coolers by Thermofin
Special features / Comments: Glycol absorbs the heat given off by the ammonia going through the plate heat exchangers. The hot glycol circuit is then used for MT defrosting and under-floor heating.
Contact:

Al Salem JCI York Refrigeration Division
Colin Hewetson
P.O. Box 30330
Al Khobar 31952
Saudi Arabia

Phone: +966 3 8588446
Fax: +966 3 8587454
Mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

www.johnsoncontrols.com