Seamus Kerr Refrigeration Chilling

8/13/2019 Seamus Kerr Refrigeration Chilling

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Refrigeration and Chilling

Reducing Electricity Costs and

improving quality


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Law of Thermodynamics

Energy cannot be created or destroyed. But

it can be changed from one form to

another.

Refrigeration costs money.


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Reducing Electricity Cost.

A. Conserve the cold you have paid for!

B. Reduce the refrigeration manufacturing

cost (efficient refrigerant plant).


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A. Cold Conservation

Room Insulation, Air Entry, Product Load, Lighting and Cooler Fans

Product, People


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A. Cold Conservation

Room Insulation (Conductive and Radiation)

Air Entry (Infiltration)

Product Load Lighting and Fans

People


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Cold Conservation

1 Air Entry (Infiltration)

2 Product Load

3 Room Insulation (Conductive and Radiation)4 People

5 Lighting and Fans


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Cold Conservation- Air Entry


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Cooling Air Costs money

94 kJ/m3 from +25 oC to 10 o C

20m x 20m x 5m room = 2000 m3

Refrigerate t0 10 oC in 1 hr

94 x 2000/3600 = 52 kW


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28.8 kW Power Input

0.085/kWhr

2.49/hr


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Poor door sealing

Average Door 3m x 3m

Average Off-set 10mm 0.06 m2 hole

300mm x 200mm


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Freezer Application 0.06 m2 hole causes loss of approx 0.03m3/s

Cooling Required = 186 kJ/m3 (+25o -25o)

5.85 kW refrigeration


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3.59 kW Power Input

0.085/kWhr

24 hrs x 365 days 3.59 x 0.085 x 24 x 365 = 2673/per door


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PROCESS

WASTE

HEAT

ENERGY

OUTPUT

ENERGY

INPUT


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AIR CONDITIONING


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EVAPORATIVE COOLING

Air-cooled heat rejection is often beingpreferred due to health & safety, watertreatment and maintenance concerns

Acknowledged cost, energy and sizeadvantages of water cooled systems are

being outweighed by safety concerns andowner responsibilities.


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EVAPORATIVE COOLING

Wet Bulb is Typically 6oC to 12oC Lower ThanDry Bulb

Lower Cold Water or Condensing

Temperature By At Least the Wet Bulb to Dry

Bulb Difference

Chiller Absorbed Power Decreases 3% ForEvery 1oC Lower Condensing Temperature


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Reduce Refrigeration Cost

A 1.53 COP

B 1.83 COP

20.0 % electricity saving on compressor +

condenser + cooler.


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Evaporative Cooling Arguments Against

Health and Safety Responsibilities

Water Treatment Requirements

Maintenance and Cleaning

Water Consumption


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Heat Recovery

PROCESS

WASTE

HEAT

ENERGY

OUTPUT

ENERGY

INPUT


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Heat Recovery De-superheater

Divert Rejected Heat to Boiler Feed Divert Rejected Heat to Wash Water

(15% of Total Rejected Heat available)

Win Win


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Mr. Seamus Kerr, RSL Ireland

THANK YOU

[email protected]

Documents

Seamus Kerr Refrigeration Chilling