Tetra Pak Jed Report
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Transcript of Tetra Pak Jed Report
Tetra Pak Jeddah Report
Introduction
The cooling system installed at Tetra Pak has gotten obsolete and has suffered
from several breakdowns in the past. In order to control, monitor and optimize
the cooling system, a building management system was installed at the facility on
22nd of September 2014.
A BMS or Building Management System is a computer-based system that is
installed in the building for controlling, monitoring and optimizing the building’s
mechanical as well as electrical equipment such as HVAC systems, lighting,
security system, etc. Building Management Systems are critical components to
managing energy demand. Improperly installed BMS can cost up to 20% of energy
usage.
The building management system has a coverage of the following areas:
Carton Factory
1. Printer Zone HVAC Systems (MCC1)
2. Laminator Zone HVAC Systems (MCC2)
3. Slitting and Palletizing Zone HVAC Systems (MCC2 Slave)
Straw Factory
1. Straw Factory HVAC System (MCC4)
The BMS grants us the ability to control and monitor all of the Chillers and the Air
Handling Units of the entire Production Building. Currently it monitors:
Chillers Inlet and Outlet Temperatures
Cooling Tank Temperatures
Outside Temperature and Humidity
Zones Temperature and Humidity
AHU return and supply Temperatures and Humidity
Air flow monitoring of AHUs
Control of AHU fan speed
Dampers Controls
CW Control Valves
This illustration shows an example of a Building Management System installed
in the Straw Factory at Tetra Pak Jeddah.
AHU1-DA1: Sensor controlling the damper that draws in fresh outside air.
AHU1-CV1: Sensor controlling the CW Valve that regulates the flow of
chilled water to enter the AHU.
AHU1: Sensor that controls the AHU’s fan speed.
AHU1-ST2: Sensor that shows the temperature of air that is being supplied.
AHU1-ST1: Sensor that shows the room temperature of the factory.
AHU1-SH1: Sensor that shows the humidity that is being drawn out from
the room.
AHU1-ST3: Sensor that shows the temperature of the air that is being
drawn out of the room.
AHU1-DA2: Sensor controlling the 2nd damper that allows the exhaust air to
circulate by mixing with the supply air.
Out-ST10: Sensor that shows outside temperature.
Out-SH10: Sensor that shows outside humidity.
Chiller Tank: Acts as a reservoir of water for the chiller to draw and release water.
CT-ST2: Sensor that shows the temperature of the hot water from where the chiller
draws in water.
CT-ST1: Sensor that shows the temperature of the cold water where the chiller
releases its chilled water.
CH7-P1A / CH7-P1B / CH-20(A – D): These sensors are installed on the pumps that
pump water from the tank towards the chiller.
CH (3 – 7)-ST1: Sensor that shows entering water temperature to the chiller.
CH-ST2 / CH7-ST2: Sensor that shows the leaving water temperature, once it has
been chilled, towards the tank.
AHU-SP1: Sensor that shows the pressure of water that is being pumped towards the
AHUs from the chiller tank.
AHU-ST1: Sensor that shows the temperature of water being pumped towards the
AHUs from the chiller tank.
AHU-ST2: Sensor that shows the temperature of water returned back to the chiller
tank’s hot area from the AHUs.
Suggestions on expanding the Building Management System
The BMS could be expanded to cover the following areas:
Chillers
There are a total of 10 chillers installed at the facility and another chiller is
currently under installation and will be put into commission soon.
Carton Factory Chillers
There are 7 chillers installed for the carton factory among which chillers 1 and 2
are installed separately. The rest of the chillers 3-7 are installed adjacent to the
carton factory.
Chiller 1 and 2
These chillers only provide comfort cooling to the Printer Zone.
Chiller 3-7
Provide process cooling to the Printer Zone.
Provide comfort and process cooling to the Laminator Zone.
Straw Factory Chillers
There are 3 chillers installed for the Straw Factory. These chillers operate
independent of the carton factory’s chillers and are responsible for the comfort as
well as process cooling of the Straw Factory.
OBJECTIVE
ANALYZE AND REVIEW THE BUILDING MANAGEMENT SYSTEM AND SUGGEST
IMPROVEMENTS
LEARN AND UNDERSTAND THE OPERATION OF CHILLERS AND SUGGEST METHODS TO
IMPROVE THE COOLING SYSTEM.
LEARN AND UNDERSTAND THE OPERATION OF AHUS AND SUGGEST IMPROVEMENTS.
Description of chillers
The aforementioned Straw Factory chillers 1, 2&3 are operating independently
and pose no major breakdowns. The area which demands attention is the Carton
Factory.
Cooling Loads
The cooling loads where the chillers are providing their chilled water include:
AHUs (Air Handling Units)
FCUs (Fan Coil Units)
Cooling Units (CUs)
Chilled Rollers (Used in Laminator as well as Printer)
Heat Exchangers
Segregating Straw and the Carton Factory into different cooling
systems
Cooling System 1 (Carton Factory)
Consists of 2 York Chillers (1 & 2) with reciprocating compressors and R22
refrigerant.
This system supplies comfort cooling to the Printer Zone (AHU-101, AHU-
102).
Chillers were installed in 1995.
The total cooling capacity of this system is 800KW.
Cooling System 2 (Carton Factory)
Consists of 5 York Chillers (3 – 7).
The chillers 3-6 are equipped with 4 screw compressors and use R407c
refrigerant. ( Chiller No 3 has been upgraded and now uses refrigerant
R134a)
Chiller no 7 is a relatively contemporary chiller. It is equipped with 3
variable speed drives (VSD) screw compressors and R134a as a refrigerant.
Supplies process cooling to the Printer Zone and comfort + process cooling
to the Laminator Zone.
Chillers 3-6 were installed in 2003.
Chiller no 7 was installed in 2010.
The total cooling capacity of this system if working properly should be
5800KW.
Cooling System 3 (Straw Factory)
This system consists of 3 chillers.
Chillers are equipped with 6 scroll compressors and uses R407c as a
refrigerant.
The chillers supply comfort and process cooling to the Straw Factory.
Installed in 2001
Chiller Structure
Chiller 3-6 and chiller 7 consists
of 4 and 3 screw compressors
respectively.
The entering water
temperature (EWT) t1 is 12⁰C,
which comes from the AHUs
and the production building
processes after being
consumed and warmed. The
water that enters is cooled
down by the chiller and now
the leaving water temperature
has been reduced by 5⁰C (∆T =
5) and now has a value of 7⁰C. This water is again sent to the AHUs to
provide with comfort cooling and to the machines in the production
building (Printer, Laminator, Slitter and Straw) to provide process cooling
and the cycles goes on.
The chiller control panel operates independently. It monitors the ∆T (t1 -
t2) and off loads 2 out of 4 compressors if the value of ∆T is high or if there
is sufficient cooling in order to optimize energy consumption.
The building management system operates rather differently. It basically
acts like a switch to the entire chiller machine, switching it off entirely. With
respect to chiller 7, the BMS switches on or switches off the rest of the
chillers 3-6. If the value of ∆T is too low, that would mean chiller 7 isn’t
providing sufficient cooling and so the BMS switches on another chiller to
compensate for it. Similarly, if ∆T is too high, chillers except for chiller 7
would be switched off accordingly to save energy.
Ambient Temperature Cutoff
The obsolete Chillers 3 to 6 were installed 12 years ago which has caused its
condenser fins to deteriorate significantly and hence are not able to
dissipate heat efficiently. Due to the damaged fins the max ambient
temperature, after which the condenser is no longer able to dissipate
anymore heat due to the extreme pressure build up and thus causes the
compressor to shut down to prevent it from receiving damage, is 42⁰C
(107.6 F).
Chiller 3 Upgradation
Chiller 3 has been upgraded and now uses 134a as a refrigerant instead of
407e, which is still being used in chillers 4 to 6.
134a, which has an empirical formula 1,1,1,2 – Tetrafluoroethane, is a halo
alkane refrigerant. It is a low pressure inert gas used primarily as a ‘high
temperature refrigerant’ for domestic refrigeration and automobile air
conditioners. Due to its low pressure characteristic, the 134a refrigerant
prevents the extreme pressure build up and allows the condenser to
operate normally beyond the max ambient temperature, 42⁰C (107.6 F).
Chiller 7, that was installed in 2010, already uses 134a as a refrigerant and
hence is capable of running normally even beyond 42⁰C.
290
260
190
399
375
290
0
159
0
50
100
150
200
250
300
350
400
450
DSCH PRESS CUTOUT DSCH PRESS UNLOAD SYS DSCH PRESS
PR
ESSU
RE
IN P
SIG
Chiller 3 upgradation comparison
CH 3 CH 4 CH 7
This graph shows that Chiller 3’s discharge pressure has been significantly
reduced after the upgradation to 134a compared to the Chiller 4, which
still uses 407e.
DSCH PRESS CUTOUT – Discharge Pressure Cutout
DSCH PRESS UNLOAD – Discharge Pressure Unload
SYS DSCH PRESS – System Compressor Discharge Pressure
CH 3 – Chiller 3
CH 4 – Chiller 4
CH 7 – Chiller 7
Chiller Status
Carton Factory
Chiller # 1
Compressor 1
Condenser Fan Unbalance
High Superheat from evaporation giving low evaporation
Compressor 2
High superheat from evaporation
Chiller # 2
Compressor 1
Large sub cooling in condenser
Excess of refrigerant
Compressor 2
Performing good
Chiller # 3
Filter Dryer
The filter dryers of this chiller have
been reoriented to vertical, which
has now improved its filtration
process of particles and the
prevention of moisture to avoid any
damage to the refrigeration cycle.
The refrigerant has been upgraded
to 134A from the previous R407C.
134A is a low pressure gas, which
has reduced its discharge pressure
and in turn enabled the
compressors to operate beyond the
max ambient temperature.
Condenser Fins
Fins are not in good condition.
Cleaning the condenser fins every
month is an easy and inexpensive
to ensure an efficient chiller.
The fins can be cleaned with a
brush-tipped vacuum or with
clean, dry compressed air; a
condenser cleaning solution can
also be used.
Chiller Readings (5th July 2015)
Compressors Status
System 1 Compressor: Running
System 2 Compressor: Running
System 3 Compressor: Running
System 4 Compressor: No Cooling Load (Switched Off)
Refrigerant
Previous Type: R407C (High Pressure Gas)
Upgraded to: 134A (Low Pressure Gas)
Discharge Pressure
Pressure Cutout: 290 PSIG (Has been significantly reduced from approx.
400 PSIG after upgrading it to 134A)
Pressure Unload: 260 PSIG (Has been significantly reduced from approx. 400
PSIG after upgrading it to 134A)
Evaporator
The evaporator plays a major role
in the operation of the chiller. It’s
responsible for converting the
water into a gas by transferring
the heat to the refrigerant and
emitting that gas into the
compressor.
The illustration clearly depicts the
old age of the evaporator, which
could be affecting its efficiency.
Temperatures
Leaving Liquid Temp: 42.4 DEGF (5.7⁰C)
Return Liquid Temp: 51.1 DEGF (10.6⁰C)
∆T = 4.9⁰C
Ambient Temp: 90.5 DEGF (32.5⁰C)
Chiller # 4
Condenser Fins
Chiller’s condenser fins are in poor
condition.
A dirty condenser prevents air from
flowing through the system and
keeps heat trapped within the
cooling system.
Clean the fins with a brush-tipped
vacuum or with clean, dry
compressed air; a condenser
cleaning solution can also be used.
Filter Dryer
Filter Drier is responsible for the
filtration of particles and the
prevention of the moisture to
circulate through the system to avoid
damage to the refrigerant cycle.
The filter drier operates more
efficiently in vertical orientation, as
observed in chiller 3.
Chiller Readings (5th July 2015)
Compressor Status
System 1 Compressor: Running
Evaporator
The evaporator of the chiller cools
the water by transferring the heat to
its refrigerant and then converting it
into a gas which is then transferred
to the compressor.
The illustration clearly shows that the
condition of the evaporator has
deteriorated significantly, which
could be seriously affecting the
chiller’s efficiency.
System 4 Compressor
The illustration shows the area which
was supposed to be occupied by
System 4 Compressor to be vacant.
This compressor of chiller 4 has been
removed for maintenance purposes.
System 2 Compressor: Running
System 3 Compressor: Switched Off
System 4 Compressor: Switched Off
Refrigerant
Type: R407C
Discharge Pressure
Pressure Cutout: 399 PSIG
Pressure Unload: 375 PSIG
Temperatures
Leaving Liquid Temp: 44.9 DEGF (7.16⁰C)
Return Liquid Temp: 51.2 DEGF (10.67⁰C)
∆T = 3.51⁰C
Ambient Temperature: 90.9 DEGF (32.22⁰C)
Chiller # 5
Condenser Fins
The fins are in poor condition.
Obsolete and damaged fins of the
condenser can cause the heat to
be trapped inside and prevent the
movement of air throughout the
system.
Clean the fins with a brush-tipped
vacuum or with clean, dry
compressed air.
Filter Dryer
Filter Driers, responsible for the
absorption of moisture to prevent
it from entering the refrigeration
cycle and for providing physical
filtration of unwanted particles.
Again, the orientation of the filter
drier must be vertical for it to
perform more efficiently.
Evaporator
The evaporator responsible for
cooling the water by converting it
into gas and transferring its heat
to the refrigerant is not in a good
condition, as shown in the picture.
This illustration shows that chiller’s 5 compressor is under
maintenance due to high discharge temperature.
Chiller Readings (5th July 2015)
Compressor Status:
System 1 Compressor: Switched Off
System 2 Compressor: Running
System 3 Compressor: Switched Off
System 4 Compressor: Switched Off
Refrigerant
Type: R407C
Discharge Pressure
Pressure Cutout: 390 PSIG
Pressure Unload: 375 PSIG
Temperatures
Leaving Liquid Temp: 48.4 DEGF (9.11 ⁰C)
Return Liquid Temp: 49.5 DEGF (9.722 ⁰C)
∆T = 0.612⁰C
Ambient Temperature: 89.4 DEGF (31.8 ⁰C)
Chiller 6
Condenser Fins
This Chiller’s condenser fins are in
very poor condition.
Obstructed fins can lead to heat
being trapped inside and preventing
the circulation of air inside the
system.
Clean the fins with a brush-tipped
vacuum or with clean, dry
compressed air.
Filter Dryer
The orientation of the filter drier
is again horizontal. In order for it
to perform its function more
efficiently, which is preventing
moisture and particles from
entering the refrigeration cycle,
the filter drier must be kept in a
vertical orientation.
Evaporator
The evaporator cools the water by
transferring its heat to the
refrigerant and converting the
water into a gas.
This chiller’s seems to have a
reciprocating evaporator, implying
that its evaporator is not the cause
for its poor efficiency.
The illustration shows that the outer covering of this chiller has
been removed to allow air flow to minimize the effect of
ambient temperature.
Chiller Readings (5th July 2015)
Compressor Status:
System 1 Compressor: Switched Off
System 2 Compressor: Running
System 3 Compressor: Running
System 4 Compressor: Switched Off
Refrigerant:
Type: R407C
Discharge Pressure
Pressure Cutout: 390 PSIG
Pressure Unload: 375 PSIG
Temperatures
Leaving Liquid Temp: 47.6 DEGF (8.667 ⁰C)
Return Liquid Temp: 49.7 DEGF (9.833 ⁰C)
∆T = 1.156 ⁰C
Ambient Temp: 92.2 DEGF (33.44 ⁰C)
System 4 Compressor
The illustration shows that
system 4 compressor of chiller 6
has been removed for
maintenance purposes.
Chiller 7
Condenser Fins
This chiller’s condenser fins are in
good condition.
Well maintained condenser fins
dissipate heat efficiently and
prevent the heat from being
trapped inside and in turn causes
the condenser to operate
efficiently.
Evaporator
The evaporator of this chiller is in
good condition.
A well maintained and a reciprocating
evaporator cools the water by
transferring its heat to the cooled
refrigerant and converting it into
vapors more efficiently than a
damaged evaporator would by
maintaining its discharge pressure
under adequate limits for the
compressor.
Filter Dryer
The filter drier removes the
moisture and prevents any
anomalous particle from entering
the refrigeration cycle.
This device must be in a vertical
orientation for better
performance.
Oil Separator
This is a centrifugal water-oil
separator designed to separate oil
and water.
It contains a cylinder that rotates
inside a larger stationary
container. Water being the denser
liquid accumulates outside and is
collected from the side, whereas
the oil being the less dense
accumulates inside and is
collected from the center.
Chiller Readings (5th July 2015)
Compressor Status
System 1 Compressor: Running
System 2 Compressor: Running
System 3 Compressor: Running
Virtual Speed Drives
These equipment are used to control
the speed of the machine where the
output speed can vary without steps
over a range of different speeds.
The speed control allow for a much
smoother operation by gradually
increasing and decreasing the
compressor system’s current, thus
preventing high surges of electric
current to start the motors resulting in
electromagnetic and thermal stresses.
Refrigerant
Type: 134A (Low Pressure)
Temperatures
Leaving Liquid Temperature: 42.1 DEGF (5.611 ⁰C)
Return Liquid Temperature: 48.6 DEGF (9.22 ⁰C)
∆T = 3.6 ⁰C
Ambient Temperature: 88.6 DEGF (31.4 ⁰C)
5.7
7.16
9.118.667
5.611
10.6 10.67
9.722 9.833
9.22
0
2
4
6
8
10
12
CH 3 CH 4 CH 5 CH 6 CH 7
TEM
PER
ATU
RE
IN ⁰
C
CHILLERS
Leaving and Return Water Temperatures
Leaving Water Temperature Return Water Temperature
Air Handling Units (AHUs)
Printer Zone
The Printer Zone is provided with comfort cooling by the following AHUs:
101-AHU
102-AHU
The following exhaust fans are installed for the circulation of air:
101-EF
102-EF
4.9
3.51
0.612
1.156
3.6
0
1
2
3
4
5
6
CH 3 CH 4 CH 5 CH 6 CH 7
TEM
PER
ATU
RE
⁰C
CHILLERS
∆T Readings of different Chillers
∆ T
Laminator Zone
The Laminator Zone is provided with comfort cooling by the following AHUs:
201-AHU
202-AHU
Exhaust Fans installed for air circulation:
201-EF
Straw Factory
The Straw Factory is provided with comfort and process cooling by the following
AHUs:
AHU1
Exhaust Fans installed for the air circulation:
EF1