INCORPORATING COLD CHAIN
PROJECT
Rear view of the MT glycol pump sets . to the MT vessel to reduce flash gas and utilise incoming / top-up condenser water to subcool the HPL before entering the MT vessel / flash economiser .
The heat from the spaces ( with the future ambient area incorporated ) is removed by means of 80 coils of 74kWR each in the 2 ° C space , 24 coils of 76kWR each in the 14 ° C space and four coils of 73kWR each in the chocolate box .
The heat required to defrost the 2 ° C coils is recovered from the discharge side of the system by means of two 200kW condensing PHEs installed in the condenser yard . This heats the warmer glycol defrost circuit from 8 ° C to 15 ° C to facilitate the defrosting of the coils in the field with waste heat from the refrigeration plant .
High quality heat is recovered from the oil systems on the screw compressors . The waste heat recovery from plant is designed for a peak heat recovery of some 317kW , although initially only 200kW will be recoverable due to the plant capacity ramping up over the life of the facility . The hot compressor oil from the discharge side is used to heat a closed loop hot water circuit from 47 ° C to 63 ° C . This is then pumped via a hotwell to the crate washer to heat the crate washer water .
Provision is made for a future heat pump , utilising the discharge gas from the primary ammonia plant and compressing it to 70 ° C saturated conditions in order to generate hot water in future , if required .
The plant has been equipped with VSD on all major component motors to ensure that part load conditions are optimised and energy savings are being realised during part loads conditions .
High efficiency EC fans were specified for the cold room . There being a total of 104 blower coils and 416 fans with a total peak power consumption of 650kW . It was extremely
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