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Presentation on
Building a Robust
Refrigeration System
By
P. Sudhir Kumar
Frick India Limited
What is a Cold Store ?
A Cold store is a building or a group of
buildings with thermal insulation and a
refrigeration system, in which various
perishable foodstuffs can be stored for
various lengths of times in set conditions of
temperature and humidity, thus slowing the
deterioration and spoilage that would occur
in a natural environment. In some countries
cold stores are known as refrigerated
warehouses.
TYPE OF COLD STORES :
PRE-COOLING
COLD ROOMS
LARGE COLD STORAGES
FROZEN STORES
IQF/BLAST FREEZING
PLATE FREEZING
HIGH HUMIDITY CHAMBERS
CONTROLLED ATMOSPHERE COLD STORES
Planning A Cold Store
SITE
PRODUCTS
STORAGE CONDITIONS
MATERIAL HANDLING
REFRIGERATION SYSTEMS
SELECTION OF SITE
A. FACTORS
 Geographical
 Economic Factor
B. CONSIDERATIONS
 Proximity to Rail/Roads
 Possibility of later expansions
 Water and Power supply
 Availability of Work Force
MAINTAINAING A COLD STORE FOR
FINANCIAL VIABILITY
Multipurpose Cold Stores

Operation round the year
Ordinary Single Product Store

Operation only for part of a year
How a Refrigeration Plant
is to be designed ?
Capacity of Plant
Refrigerant
Type of Cooling
 Direct
 Secondary
Selection of refrigeration equipment
Choosing the Right refrigerant
Why Ammonia ?
Less expensive to install
Easy to operate
Highly reliable
Easy to modify or expand
Safe
Self-Alarming
Environmental issue and natural refrigerants
Depletion of Ozone Layer
Global Warming
 Montreal Protocol (1987)
 Kyoto Protocol (1997)
 CFC : Fazed out in 1996
 Requires : Reduction 6% of green
house gases compared to 1990
level (First target annual : 2008~2012)
 HCFC : Regulation starts in
2004 to be fazed out by 2020
 Regulated gases : 3 gases such as HFC
Recovery and disposal of Fluoro-carbon (Freon) law : Refrigerants CFC, HCFC, HFC
PRTR :Aw (Chemical Control promotion law ) : HCFC22, HCFC123, EG Brine etc.
Utilization of natural
refrigerants
Comparision of refrigerant characteristics
100 years
Safety
Group
COP
ratio
Refrigeration
Capacity
Discharge
Pressure MPa
Discharge
Temp. 0C
.055
1700
A1
1
1
1.53
57.5
HFC-R134a
0
1300
A1
0.99
0.91
1.02
44.5
HFC-R404A
0
3870
A1/A1
0.89
0.68
1.83
44.8
HFC-R407C
0
1650
A1/A1
0.99
0.99
1.64
53.6
HFC-R410A
0
1980
A1/A1
0.93
1.0
2.41
57.2
HFC-R507A
0
3850
A1
0.88
0.65
1.88
44.4
R717(Ammonia)
0
<1
B2
1.04
6.90
1.55
93.3
R290(Propane)
0
3
A3
0.97
1.71
1.37
44.2
R600a(Isobutane)
0
3
A3
1.01
1.66
0.53
40.0
R744(CO2)
0
1
A1
0.63
0.85
9.0
72.0
Refrigerant
HCFC-R22
OD
P
GWP
Tc/Te = 40/00C (Sc = Sh=00C) (Calculated by REFPROP V6.01)
ODP : Ozone Depletion Potential
COP and Refrigeration capacity ratios are compared with R22
GWP : Global Warming Potential
Discharge pressure at discharge temperature of 400C
Safety group is according to AHRAE standard safety group 34
A: Lower Toxicity, B : Higher toxicity 1: Nonflammable, 2: Flame resistant 3: Inflammable
Ammonia – A Natural Refrigerants

Ammonia is a colourless gas that liquefies under pressure
and has a pungent odour.

Ammonia is considered a natural refrigerant because it
occurs in nature’s material cycles.

Ammonia is also an ideal refrigerant from a climate
protection point of view

It contributes neither to ozone depletion nor to global
warming .

Ammonia has no ozone depletion potential (ODP = 0) and no
direct greenhouse effect (GWP = 0).

Ammonia is combustible only to a limited degree; its ignition
energy is 50 times higher than that of natural gas
Source : eurammom-information No.2/August 2005
Ammonia – A Natural Refrigerants

Thermodynamic properties :means that its indirect global
warming potential is also very low.

Plants that use ammonia as opposed to other refrigerants
have a better TEWI (Total Equivalent Warming Impact).

The TEWI is the sum of the direct global warming impact –
caused by the refrigerant lost through leakage and recovery
Source : eurammom-information No.2/August 2005
EQUIPMENT FOR THE
REFRIGERATION SYSTEM
COMPRESSORS
CONDENSERS
EVAPORATORS
RECIRCULATION SYSTEMS
AUTOMATION
Most Popular & Successful Compressors are :
Rotary Twin Screw Compressor Package
Reciprocating Compressors
Frick India high Speed
Reciprocating compressors
Capacity Range : 108.9kW to 864 kW
CFM Range : 99.4 to 796
Frick India Limited
Advantages of High speed Reciprocating
Compressors

Latest advancement in refrigeration compressor technology now
manufactured and assembled in India.

Runs at 730 rpm to 1200 rpm.

High efficiency and high performance.

Smooth unloading system for power saving.

Low vibration and noise.

Tolerance measured in light bands rather than thousandths of
inches.

Advance filter removes 95% of contaminants as small as 3 micron
in size.

Oil pressure is maintained even at very low suction pressure.

Double bellows shaft seal.

Installation can be done almost anywhere, even at top floor.
EVAPORATORS
Horizontal Discharge
Vertical Discharge
CONDENSERS
Evaporative Condenser
Evaporative Condenser
• Less Space, no civil work required.
• Less Connected pump & fan motor.(at least 50%)
• Combination of S/T Condenser & Atmospheric
Condenser.
• Run at lower condensing Temp – means BKW /
TR of Compressor come down and it will reduce the
power cost
Ammonia Re-Circulation Systems
Superb refrigerant distribution
Lower inlet liquid temperature
Cut down capital costs
Low maintenance
Protection of compressors from liquid slugs
Tremendous power saving in operation.
Advantages of using Re-circulation System
Automation system For Refrigeration Plant
Controlled Parameters
Ease of Operation
Flexible Load
Power Saving
Automation in Refrigeration Plant Operation.
Total Plant Control. centralized temperature recorder and
interlocking electric circuit for various process controls can be
interlocked to your PC/PLC
Additional advantageous of VFD drive
When an induction motor is connected to a full voltage supply, it draws
several times ( up to about 6 times) its rated current. As the load
accelerates, the available torque usually drops a little and then rises to a
peak while the current remains very high until the motor approaches full
speed.
By contrast, when a VFD starts a motor, it initially applies a low
frequency and voltage to the motor. The starting frequency is typically 2
Hz or less.
Thus starting at such a low frequency avoids the high inrush current that
occurs when a motor is started by simply applying the utility (mains)
voltage by turning on a switch.
After the start of the VFD, the applied frequency and voltage are
increased at a controlled rate or ramped up to accelerate the load without
drawing excessive current. This starting method typically allows a motor
to develop 150% of its rated torque while the VFD is drawing less than
50% of its rated current from the mains in the low speed range.
A VFD can be adjusted to produce a steady 150% starting torque from
standstill right up to full speed.
FRICK INDIA LIMITED
SAFETY IN COLD STORE
FIRE SAFETY
 Causes of Fire
 Potential Hazards
 Fire Prevention in protecting the cold store
 Fire prevention and fire safety equipment
 Fire precautions
SAFETY FROM ACCIDENTS
 General precautions
 Preventing accidents due to poor design
 Precaution against getting trapped in a freezing room
 Precaution against refrigerant leak
 Water safety measures
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