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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 : 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
PRE-COOLING
COLD ROOMS
LARGE COLD STORAGES
FROZEN STORES
IQF/BLAST FREEZING
PLATE FREEZING
HIGH HUMIDITY CHAMBERS
CONTROLLED ATMOSPHERE COLD STORES
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
Depletion of Ozone Layer
Environmental issue and natural refrigerantsEnvironmental issue and natural refrigerants
Global Warming
Montreal Protocol (1987)
CFC : Fazed out in 1996
HCFC : Regulation starts in 2004 to be fazed out by 2020
Kyoto Protocol (1997)
Requires : Reduction 6% of green house gases compared to 1990 level (First target annual : 2008~2012)
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 characteristicsComparision of refrigerant characteristics
Tc/Te = 40/00C (Sc = Sh=00C) (Calculated by REFPROP V6.01)COP and Refrigeration capacity ratios are compared with R22Discharge pressure at discharge temperature of 400CSafety group is according to AHRAE standard safety group 34A: Lower Toxicity, B : Higher toxicity 1: Nonflammable, 2: Flame resistant 3: Inflammable
Refrigerant ODP GWP100 years
Safety Group
COPratio
RefrigerationCapacity
DischargePressure MPa
DischargeTemp. 0C
HCFC-R22 .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
ODP : Ozone Depletion PotentialGWP : Global Warming Potential
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 RefrigerantsAmmonia – 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
Ammonia – A Natural RefrigerantsAmmonia – A Natural Refrigerants
COMPRESSORS
CONDENSERS
EVAPORATORS
RECIRCULATION SYSTEMS
AUTOMATION
COMPRESSORS
CONDENSERS
EVAPORATORS
RECIRCULATION SYSTEMS
AUTOMATION
EQUIPMENT FOR THE REFRIGERATION SYSTEM
EQUIPMENT FOR THE REFRIGERATION SYSTEM
Most Popular & Successful Compressors are :
+Rotary Twin Screw Compressor Package
+Reciprocating Compressors
Frick India Limited
Frick India high Speed Reciprocating compressors
Frick India high Speed Reciprocating compressors
Capacity Range : 108.9kW to 864 kWCFM Range : 99.4 to 796
Advantages of High speed Reciprocating Compressors
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.
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.
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 LIMITEDFRICK INDIA LIMITEDSAFETY 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