GlaxoSmithKline - Armstrong International€¦ · GlaxoSmithKline El Salam Cairo, Egypt STEAM AND...
Transcript of GlaxoSmithKline - Armstrong International€¦ · GlaxoSmithKline El Salam Cairo, Egypt STEAM AND...
GlaxoSmithKline El Salam Cairo, Egypt
STEAM AND CONDENSATE AUDIT P 30432
Rossen IVANOV ���� + 32.42.40.90.89 [email protected]
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 2 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
TABLE OF CONTENTS
1 EXECUTIVE SUMMARY .................................................................................................................................................4
2 STEAM BUDGET AND SUMMARY OF POTENTIAL SAVINGS .............................................................................7
3 OPTIMIZATION PROJECTS ..........................................................................................................................................8
ECM1: REDUCE BOILER BLOW DOWN RATE ..........................................................................................................................9
ECM 2: IMPROVE BOILER EFFICIENCY ..................................................................................................................................14
ECM 3: REPLACE STEAM BY HOT WATER TO HEAT 60°C HOT WATER LOOP ......................................................................25
ECM4: INSULATE STEAM PIPES ANCILLARIES .......................................................................................................................28
ECM5: STEAM TRAPS REPLACEMENT ..................................................................................................................................30
ECM6 REPLACE CONDENSATE TANK BY PUMPING TRAP PACKAGE ....................................................................................32
ECM7: INSTALLATION OF PROPERLY SIZED DRIP LEGS AND TRAPS ON THE INLET OF PLANT STEAM CONTROL VALVES, ON
HEADERS AND MAIN LINES......................................................................................................................................................35
4 COMPLETE CHECK LIST OF ALL VERIFICATIONS DONE DURIN G THE AUDIT ..........................................38
5 COMMENTS ON STEAM & CONDENSATE NETWORK .......................................................................................39
STEAM PRODUCTION .............................................................................................................................................................39
STEAM DISTRIBUTION .............................................................................................................................................................41
STEAM CONSUMERS ...............................................................................................................................................................42
5.1.1 60°C Hot water Tank ........................................................................................................................................42
5.1.2 Laundry ..............................................................................................................................................................42
5.1.3 Ceph’s ................................................................................................................................................................43
5.1.4 Factory area ......................................................................................................................................................47
CONDENSATE RETURN NETWORK .........................................................................................................................................51
APPENDIX ................................................................................................................................................................................53
RADIATION LOSSES CALCULATIONS .............................................................................................................................60
INSTALLATION MISTAKES ................................................................................................................................................62
STEAM TRAP SURVEY .........................................................................................................................................................71
LIST ON EXCEL CHART .......................................................................................................................................................71
STEAM PRESSURE CONTROLLED HEAT EXCHANGERS AT LOW LOAD .............................................................72
CURRENT SITUATION ...............................................................................................................................................................72
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 3 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
OPTIMIZATION .........................................................................................................................................................................74
Closed loop pumping trap .................................................................................................................................................76
Posipressure system ...........................................................................................................................................................77
Safety drain........................................................................................................................................................................78
Barometric leg ...................................................................................................................................................................78
Condensate level control ...................................................................................................................................................79
Mixing valve on the product side .......................................................................................................................................80
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 4 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
1 Executive summary
Armstrong Service has conducted from 9th to 14st of October 2012 a complete audit of your steam
installation.
GSK Cairo is using around 1500 kg/h of 6 bar steam, for a total consumption of about 13000 T/year.
Steam production is handled by 2 fire tube boilers running alternatively.
The site is divided in several buildings:
• Ceph’s
• Factory
• Laundry
Operating hours depends on each building but generally the boiler house runs 24h/24h, 7 days/week,
52 weeks/year.
Steam is mainly used for:
Area Equipment
Ceph’s Pure steam generator
Distiller
Munters air Coil
Factory Munters air Coils AHU Coils
Hot water Tanks
Vertical Exchangers for Sirup
Sirup Tanks
Purified hot water Generator
Laundry Dryers
Press iron
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 5 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
The aim of this audit was to clearly identify potential optimisations and savings opportunities.
Consequently, the audit was particularly focused on:
- Improvements in boiler room (recovery on exhaust gas and blowdown…)
- Improvements on the heating devices drainage
- Improvements on the heating control
- Correction of design mistakes
We wish to thank particularly the mechanical team, Boiler house Team and Amr Mohamed Alaa Ibrahim
for his help during this audit.
This audit has confirmed possibilities of improving the efficiency of your steam system and realising
additional savings on your yearly global invoice.
In the boiler house, global efficiency could be enhanced by changing the adjustment of the Boilers’
burners, installing an economiser, preheating the comburant air and reducing a little bit the blow
down when the water analysis are good.
On network and steam users, drip legs instead of ½ or ¾ inch condensate pipe should be added,
especially before control valves to avoid condensate accumulation and valve/seat erosion.
On Ceph’s condensate network, the steam trap and pumping trap must be cancelled.
Steam on 60°C water Tank can be replaced by flash s team or condensate.
Low temperature steam users must be implemented. You could increase the global efficiency by
using assistance drainage to ensure better condensate elimination.
The TD process steam trap must be changed by mechanical type.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 6 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
All steam ancillaries must be protected with insulation jackets.
Potential energy savings could be at least 19% of the current yearly steam budget, which represents
a yearly saving of about 1835 MWh, 334 tons of CO2 and 73 426 Egypt pound.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 7 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
2 Steam budget and summary of potential savings Taking in consideration 2011 steam consumption, we have estimated the yearly budget for steam.
Average cost 26.0 Egyptian Pound/T
Yearly steam consumption 13000 tons/year*
Annual cost (Gas cost) 337 901 Egyptian Pound
Note:
The gas invoice for the first 8 months in 2012 is: 248 463 Egyptian Pound
The annual cost will be: 390 830 Egyptian Pound
Your cost of gas and steam is relatively low, which explains the longer than usual payback for some of
the solutions proposed.
Summary of identified energy-saving optimizations a nd their estimated yearly results: ECM n° and Name Savings Savings Investment Payback CO2
saving
MWh Egyptian Pound /year
Egyptian Pound
months T/year
1. Reduce Boiler Blow down Rate
68 2705 0 1 12
2. Improve Boiler efficiency
556 22233 200000 108 101
3. Replace steam by hot water to heat 60°C Hot water loop
312 12490 40000 38 57
4. Insulate steam pipes ancillaries
385 15423 55000 43 70
5. Steam traps replacement
514 20575 38500 22 94
TOTAL 1835 73426 333500 55 334
6. Replace Condensate tank by pumping trap package
64000
7. Improvement of steam quality
45000
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 8 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
3 Optimization projects
General considerations:
Following projects are proposal of improvement of your global steam and condensate installation.
These projects can be directly linked to a countable saving or to an increase of reliability of
system or also permit to establish better practices in the follow up of your installation (monitoring
of steam/condensate flow, drawing up of check list data sheets…).
At this stage, indicated savings and investments are still estimations and are given with a
precision of:
• +/- 25% for investments;
• +/- 15% for savings.
To establish our calculation, we have considered the following parameters:
• annual working time: 8700h for the factory (corrected for different devices)
• average steam flow: 1500 Kg/h
• fuel cost: 40.0 Egyptian Pound/MWh
• steam generation global efficiency: 80%
• steam cost: 26.0 Egyptian Pound/T
• annual CO2 emissions (51 kg/GJ / 183 kg/MWh HHV)
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 9 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
ECM1: Reduce Boiler Blow down Rate
Current System Description and Observed Deficiency
Water treatment
Softened Make up water is mixed with condensates in injection in the feed tank.
The water flow is adjusted by a manual valve. It will be better to feed a Tank with softened water, on-
off level control and add softened water to the feed tank with a control valve.
Condensate return
2 condensate lines are connected to the feed tank one from Ceph’s and one from factory.
Feed tank
The temperature on inlet water pipe just in front of the Boilers pumps was often more than 90°C.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 10 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Inlet water boiler ”Likoni” – September 7th afternoon and September 8th morning
When we started the audit, you were losing flash steam at the vent pipe, after the modification at
Ceph’s (see section Condensate return network) condensate return pipe, this loss was reduced.
Boilers blow down
Blow downs are controlled by bottom solenoid valves.
The valve is opened 120 seconds each 45 minutes, which is not necessarily based on the water
analysis.
You could decrease a little your blow down with correct daily analysis.
The TDS value was 2400 micro-siemens cm and you can accept 4500.
The Feed water TDS value was 370 micro-siemens cm.
The blowdown % was more than 15%.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 11 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
The plant operates two shell boiler at a steam pressure of 6 bar (g). The average steam load is 1.4 t/h.
Currently, the boiler blow down is controlled by:
- Opening a solenoide valve 32 times per day for 120 sec.
There is no heat recovery installed on the blow down. According to the plant’s water analysis, the
average values are:
The upper limits recommended by the local water treatment company are from 4000 to 4500
microSiemens/cm.
Technical Discussion Even with the best pretreatment programs, boiler feed water contains some degrees of impurities such
as suspended and dissolved solids. As water evaporates, these impurities are left behind and they
accumulate inside the boiler. The increasing concentration of dissolved solids leads to carryover of
boiler water into the steam, causing damage to piping, steam traps and even process equipment. The
increasing concentration of suspended solids forms sludge, which impairs boiler efficiency and heat
transfer capability.
To avoid boiler problems, water must be periodically discharged or “blown down” from the boiler to
control the concentrations of suspended and total dissolved solids in the boiler water. Surface water
blow down is often done continuously, to reduce the level of dissolved solids, and bottom blow down is
performed periodically to remove sludge from the bottom of the boiler.
Average Water Analysis Results
Ygnis
Boiler
Water
Cleaver
Brooks
Boiler
Water
Feed Water Blow down %
Conductivity µs/cm 2400 2200 370 18
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 12 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
The importance of boiler blow down is often overlooked. If the blow down rate is too high, energy
(water, fuel, chemicals) is wasted. If high concentrations are maintained, (too low blow down) it may
lead to scaling, reduced efficiency and to water carryover into the steam, compromising its quality (wet
steam). The blow down rate is calculated with the following formula:
% Blow down = C Feedwater
(C Boiler – C Feedwater)
Where:
CFeedwater= the measured concentration of the selected chemical in the feed water (Conductivity, TDS,
Alkalinity, Chlorine)
CBoiler = the measured concentration of the same chemical in the boiler
Note that the feed water concentration depends on the make-up water quality and the condensate
return ratio.
The ASME guidelines "Consensus on Operating Practices for the Control of Feed water and Boiler
Water Quality in Modern Industrial Boilers," shown in the tables below, are frequently used for
establishing optimum blow down rates.
Table 1: Water Chemistry for Firetube Boilers - ASM E Guidelines
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 13 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Recommended Optimization Armstrong recommends reducing the blow down rate by:
- Increasing time between 2 blowdowns
- Adjust the time in accordance with the analysis
It is advised to consult your boiler water treatment vendor before changing the boiler feed water
treatment program.
Estimated Investment and Payback
Present Proposed Savings
Fuel used LSHS LSHS
Steam Demand kg/h 1500 1500
blowdown % 15 8
Boiler Efficiency
(LHV) % 79,6 80,34
Heat Required Kw 1120 1113 35.2
Hours of operation h 8700 8700
Heat Required
(HHV) Mw/year 10827 10759 68
Gas Cost Egypt Pound 40/Mwh 40/Mwh
Annual Costs Egypt Pound /year 433065 430360 2705
CO2 emissions t/year 1981 1969 12
Decreasing your blow down rate from 15 to 8 % will save 2705 Egypt Pound/yr of Gas.
The CO2 emissions reduction resulting of improving the blow down is 12 ton/year
Estimated investments: The investment is estimated at 0 Egypt Pound, as only an internal analysis is required.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 14 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
ECM 2: Improve Boiler efficiency Current System Description and Observed Deficiency
Steam generation
Steam production, at 6 bar, is handled by 2 fire tubes boilers.
Ygnis - 5T/h - 3 passes boiler Cleaver BroOKs - 3T/h - 2 passes boiler
We did the “Combustion efficiency measurement”.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 15 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
You found a good combustion analysis for the Ygnis boiler. The excess air was correct, 18%.
You found a correct combustion analysis for the Cleaver Brooks boiler but not so good than the other.
The excess air was more than 50%.
The burners are modulating but you work like On-Off control on Ygnis boiler.
We put a PT 100 probe at the chimney to follow the fluctuation of the combustion.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 16 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Ygnis Boiler
The red curve is the stack temp
The green curve is the blowdown temp
The blue curve is the feed water temp
The stack temp increases when you add feed water. The burner started each 12 minutes during 6
minutes, then stopped.
The blowdown valve opens each 45 minutes during 2 minutes.
The pump is on 2 minutes each 12 minutes. The pump flow is 8.5m3/h. The average water flow was
8.5:6=1.4m3/h
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 17 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Cleaver Brooks
The red curve is the stack temp
The green curve is the air temp
The blue curve is the feed water temp
The stack temp increases when you add feed water. The burner runs in high load each 10 minutes
during 2-3 minutes. The burner never stopped.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 18 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Energy recovering systems
There is no economiser, no blowdown energy recovering system, no comburant air preheating
system.
The stack temperature is higher than 180°C, with na tural gas, you can decrease this temperature to
120°C and reduce the gas consumption by around 3 %.
You can reduce the blowdown time and recover a part of the Energy to heat the softened water.
You can take the comburant air at the top of the boiler to increase the temperature
The green curve is the bottom air temp
The blue curve is the top air temp
During the day the difference is between 10 and 15°C.
During the night, the difference is between 15 and 20°C.
BOILER EFFICIENCY (see next page)
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 19 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 20 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Boiler 1 is Ygnis with losses from burner cycling.
Boiler 2 is Cleaver Brooks, with high excess air and high stack temperature
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 21 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Note: The indicate cost are not euro but Egyptian Pound .The steam cost is a little different from the
26 Egyptian Pound/T considered in the chapter 2.
The difference is coming from the average steam flow and gas HHV.
Technical Discussion
The plant operates a Shell tube boiler rated for 5 T/hour at 6 bar. The average steam generation
is 1400 Kg/hr. A combustion analysis of the boiler flue gas was conducted during the Audit. The
results of the analysis are as follows:
Combustion Analysis
Boiler Load % 25
Stack
Temperature
°C 180
Ambient
Temperature
°C 30
CO2 % 10
Efficiency % 83,7
Excess Air % 18
O2 % 3,46
CO ppm 0
During combustion, the carbon from the fuel combines with the oxygen and gets converted in to
CO2. This oxidation reaction is exothermic and liberates heat. This heat is absorbed by the
water on the water-side of the boiler, which is converted into steam. The gases of this reaction
are exhausted via the stack of the boiler at a temperature close to the saturation temperature of
the steam. The energy contained in these exhaust gases accounts for a major part of the
efficiency loss of a boiler.
It is therefore important to recover the maximum amount of energy out of these gases by using
economizers.
An indirect heating type economizer consists of a coil heat exchanger, with finned or un-finned
tubes, placed in the exhaust gas flow as a section of the ductwork or stack. With this type of
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 22 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
economizer, the water flows through the tubes and absorbs the excess heat from the flue gas.
Typically, a deaerated feedwater is used for this purpose as a heat sink.
Your Combustion analysis is very good, but you have no continuous operation.
During our analysis, the burner started each 12 minutes during 6 minutes, then stopped.
When it starts, there is a pre-venting action during 40 sec and you therefore lose some Energy.
Recommended Optimisation
• Armstrong recommends checking the burner and input the correct parameters to decrease
the low firing set point.
• Armstrong recommends installing a stainless steel feedwater economizer to recover the heat
from boiler flue gases and improve the boiler efficiency.
• The intake air could be increase from 30 to 40°C i f you suck it from the top of the boiler.
Example of installation:
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 23 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
The system consists of an economizer with control instrumentation in the flue gas and the feed water
paths. The water passes through the tubes. The control valves maintain and modulate water flow as
per the boiler requirement. In case the boiler does not require more feed water, a secondary back
pressure control valve would open to the DA to keep the circulation of the feed water in the economizer.
A by-pass interlock on the flue gas side ensures the stack temperature stays above the specified
minimum limits.
Estimated Benefits
Reducing the stack temperature from 180°C to 120°C will increase the boiler efficiency from
80% to 84% and will save annually 13 230 Egypt Pound.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 24 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Present Proposed Savings
Fuel used LSHS LSHS
Steam Demand kg/h 1500 1500
Excess O2 in Stack % 3.4 3.4
Combustion air
Temperature °C 30 40
Flue Gas Temp at
Boiler Outlet °C 180 180
Flue Gas Temp at
Economizer Outlet °C NA 120
Boiler Efficiency
(LHV) % 89 93
Heat Required(LHV) Kw 1113+1118 1058 35.2
Hours of operation h 4350 8700
Heat Required
(HHV) Mw/year 10783 10227 556
Gas Cost Egypt Pound 40/Mwh 40/Mwh
Annual Costs Egypt Pound /year 431326 409093 22233
CO2 emissions t/year 1973 1872 101
Estimated Investment and Payback
The investment is estimated at 200 000 Egypt Pound. It includes:
• Economizer
• Control mechanism flue gas side
• Control mechanism on feedwater side
• Modification in ducting and piping, instrumentation
• Engineering
• Installation and commissioning
The biggest part (about 80%) of both the investments and the savings are linked to the installation of
the economizer.
The payback of this installation is expected to be 9 years.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 25 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
ECM 3: Replace steam by hot water to heat 60°C Hot water loop Current System Description and Observed Deficiency
Behind the boiler house, a connection pipe from the Laundry steam pipe feeds the 60°C Hot water
Tank.
The control is done by a thermostatic valve, and the steam trap technology is a float trap.
There is no drip leg to protect the control valve.
The set point is 60°C but in fact the Tank temperat ure was more than 75°C.
The control valve is leaking even the set point temperature is OK.
You consume more steam than you expect.
The 60°C hot water Tank is heated by a steam coil, 0.1 to 0.15 T/hour at 6 bar. The Condensate Tank
has an average temperature around 90°C.
You lose a part of the energy through the flash steam at the vent.
Technical Discussion
The temperature of the 60°C water loop was more tha n 70°C, the thermostatic control valve was not
totally closed. You have possibility to replace the Steam coil by a hot water heat exchanger.
Recommended Optimisation
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 26 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Armstrong recommends replacing the steam usage by a hot water loop from the condensate Tank.
We suggest the installation of a plate heat exchanger fed by the condensate.
The return pipe after the exchanger will be connected at the vent pipe of the feed tank to condense the
flash steam. The existing system will be maintained, but used only if not enough heat is delivered by the
condensate tank.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 27 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Estimated Benefits
By using hot water loop instead of steam, you can save 100 to 150Kg/h of steam.
Existing Proposed Savings
Steam Consumption Kg/h 100-150 0-50 50-100
Boiler Efficiency (LHV) 80 80
Operating Time h/year 8000 8000 same
Gas Consumption Mwh/year 416,0-624 208 208-416
Gas Cost Egypt Pound 40/Mwh 40/Mwh
Annual Cost
Egypt
Pound/year
16652-
25000 8326 8326-16652
CO2 emissions t/year 76-114 0 38-76
Estimated Investment and Payback
The investment is estimated at 40 000 Egypt Pound. It includes:
• Plate Heat Exchanger
• Pump
• 3 way valve
• valves
• Installation
The payback of this installation is expected to be 3 years.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 28 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
ECM4: Insulate steam pipes ancillaries Current System Description and Observed Deficiency
During the audit, we listed all pipes equipments (valves, filters, separators) that are not insulated. Non-insulated parts imply a loss of energy by radiation. It means higher fuel consumption in the boiler house.
Recommended Optimization
We advise you to install insulated jackets on all pipes equipments. They protect very well the equipments and are easy to install or remove.
Wrap: Glass fiber silicone double face Thermal resistance 270°C uninterrupted Weight: 575G/m 2 Insulation: Glass wool, 50mm, density 35kgs/m3 Seam: wire of Teflon glass Fixing: Bent straps Details concerning equipments to insulate and energy losses are listed in appendix.
It represents a total energy loss of 34 900 W that is equivalent to a steam loss of about 50 kg/h, more
than 3.5% of your steam consumption.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 29 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Estimated Benefits
, .
Estimated Investment and Payback
Budgetary cost to insulate pipes and add insulated jackets is 55000 Egypt Pound It includes:
• Statement of dimensions on site • Insulation equipments supply • Installation
Payback time is about 40 months.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 30 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
ECM5: Steam traps Replacement
Current System Description and Observed Deficiency
There are 47 steam traps installed on your network. A trap survey was done during our audit. 47 steam
traps were identified. 11 of the installed traps were out of service. 19 of the traps were failed (11
leaking, 8 plugged or flooded).
Recommended Optimization
Leaking steam traps mean losses of steam. It may also reduce condensate evacuation from process by
creating a back-pressure in the return lines.
Besides, steam in condensate return lines may generate water hammers which can damage your
installation and ancillaries (valves, pressure reducing valve, heat exchangers).
Blocked traps compromise steam quality and cause corrosion and erosion of steam lines and
auxiliaries, resulting in high maintenance costs and increased down time due to system failures. These
traps should be individually evaluated and should be cleaned or replaced by correctly sized and
installed traps.
We highly advise to carry out traps surveys on a regular basis (once per year) in order to insure a good
reliability of the steam and condensate network.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 31 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Estimated Benefits
Fuel savings
Steam losses calculated kg/h 75
Energy loss kW 43
Operating hours hr 8700
yearly Energy used MWh/year 374
boiler efficiency % 80%
Fuel used
MWh/year
hhv 514
Fuel unit costs
Egypt
Pound/MWh
hhv 40
Fuel costs
Egypt Pound
/year 20575
CO2 savings
Energy used MWh/yr 514
CO2 emissions kg CO2/MWh 183
CO2 produced t/yr 94
Replace leaking traps would save 20575 Egypt Pound /year .
Estimated Investment and Payback
The budgetary cost for replacing leaking traps is 38 500 Egypt Pound .It includes:
- Equipments supply (traps)
- Installation by a mechanical contractor
- Project management
Payback time for replacing all failing traps, including blocked traps, is 22 Months.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 32 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
ECM6 Replace Condensate tank by pumping trap packag e
Current System Description and Observed Deficiency
All condensate from the factory returns to an atmospheric tank.
An electric pump sucks the hot water from this tank to transfer it to the feed tank.
You have cavitation problems with the electric pump.
The capacity of the tank is high and there are also some radiation losses due to lack of insulation.
The tank temperature was more than 100°C
You have some steam trap leaking and the vent pipe diameter is too small.
You have some problem to evacuate correctly the condensate of the farthest process.
The pipe diameter after 90°C tank is 20mm and you c onnect the 4 steam traps from the Soft gelatine
Dehumidifier coils.
We recommend you to increase the diameter of this pipe from 20 to 50 mm.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 33 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Technical Discussion
Condensate at about 100°C will flash (revaporise) a t the suction entry of the pump.
To avoid cavitation, you have to put the pump 4 m under the tank in order to create sufficient NPSH.
It is not possible in your installation.
Recommended Optimization
We propose to replace the Tank by a mechanical condensate pump package
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 34 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
This pump will discharge condensate to the existing condensate recovery line.
Estimated Benefits
This will decrease your electric consumption and reduce your maintenance cost.
Estimated Investment and Payback
The Budgetary cost to install a package pump with all equipment (Air vent, drip leg at motive steam line). Is estimated at 64 000 Egypt Pound with 1 pump
96 000 Egypt Pound with 2 pumps (1 for replacement) It includes:
• equipments supply • Installation
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 35 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
ECM7: Installation of properly sized drip legs and traps on the inlet of plant steam control valves, on headers and main lines
Current System Description and Observed Deficiency
Our study has also permitted to detect that the plant steam headers and inlet of control valves do not
have proper sized drip legs. Furthermore, in many locations, drain pocket and drain traps are missing.
As a result, plant steam is getting wet and most of the control valves are leaking from gland. It has a
bad effect on control valve trim life and profile.
Technical Discussion
The correct size of a drip leg depends on the diameter of the pipe, refer below figure and table.
Height H1 > H minimum
1. Local drained Traps
Height H1 > H minimum
2. Traps Connected to condensate Recovery
HH1
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 36 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Figure 6: Proposed configuration for the drip-leg
Steam line Size D H
for Supervised Warm-up
H for Automatic
Warm-up 15NB 15NB 250 mm 710 mm
20NB 20NB 250 mm 710 mm
25NB 25NB 250 mm 710 mm
40NB 40NB 250 mm 710 mm
50NB 50NB 250 mm 710 mm
80NB 80NB 250 mm 710 mm
Table 16, Recommended Drip-leg diameter and Height
The direct savings from these corrective proposals are difficult to estimate. There is no direct steam
loss. The equipment performance after the missing drainage is affected. The plant personnel could
count the number of valves, regulators, flanges and plates that have been changed due to early
corrosion and pitting, and how much manpower for repair and replacement was necessary.
Moreover, due to moist steam, the ejector requires more steam for creating same vacuum level. It also
leads to more erosion and change in bore size of ejector nozzles which could further increase the
steam consumption, if not checked and replaced periodically.
Recommended Optimization
Armstrong recommends the installation of properly sized drain pockets and a trap in missing locations
before steam control valve and steam header.
Estimated Benefits
The main benefits from this optimisation are:
• Reduced valve maintenance cost
• Reduced steam pipe erosion and corrosion
• Reduced down time
• Increased Heat transfer efficiency
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 37 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Estimated investment
The preliminary estimate of the project cost to implement the above recommendations is 45 000 Egypt
Pound
It includes:
• Installation of 11 properly sized drain pocket
• Installation of 11 steam trap stations with connector and integral blow down valve.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 38 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
4 Complete check list of all verifications done dur ing the audit
Potential optimisation Status Comments
STEAM GENERATION
Steam pressure setting OK 7Bar(g) Maximum boiler pressure. Necessary for Ceph’s Process
Feed water temp. to the boilers OK A little bit too high
Stack temperature Not OK You can reduce the temp by installing an economiser (see Project 2)
Combustion air temperature OK Ambient temperature is high, but could be increased by 10°C (see Project 2)
Oxygen rate Not OK Could be improved on boiler 3T (see Project 2), OK on boiler 5T
Boiler sizing Not OK Boiler 5T is oversized, but replacement could not be justified only based on energy-savings.
Boiler blow down rate Not OK A little bit too high (see Project 1)
Deaerator pressure n.a. Non–pressurized hot well. High condensate return and low steam load. Pressurized DA to save chemicals not feasible
Feed-water pre-heating Not OK See stack temperature (Project 2)
Boiler stand-by time and volatility of steam demand
Not OK You change the boiler in service each 4 hours
Boiler blow-down recovery Not OK Could be improved, but the payback is too long
STEAM DISTRIBUTION
External leaks of steam or condensate from pipes, flanges, etc.
OK Ok, system is generally well maintained
System design, trapping points etc.
Not OK Some drip legs are missing (see Project 7).
Insulation Not OK
No Insulation on all steam equipments (see Project 4).
Steam quality poor Blocked steam traps on drips compromise steam quality. High risk for erosion, corrosion and water hammering issues (see Project 7).
STEAM USERS
Condensate drainage and air venting from heat exchangers
Not OK Closed loop pumping trap arrangements for heat exchangers in a stall condition must replace blocked traps
Steam traps Not OK See trap survey results (Project 5).
CONDENSATE AND FLASH STEAM RECOVERY
Condensate recovered Not OK Lot of by pass to the sewer open. Condensate return rate is too low. Condensate tank could be replaced by pumping trap (see Projects 5 and 6).
Sizing of condensate return lines OK
Flash steam recovery Not OK From Ceph’s condensate temperature is high (see Project 3).
Water hammering Not OK Condensate go to the sewer to reduce water hammering (excessive pressure in the condensate return)
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 39 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
5 Comments on Steam & Condensate Network
Steam Production
Steam flow You put a steam flow meter between the boiler 5T/h and the main header.
We collect the value to analyse your steam consumption.
date/hour time total steam steam flow
10-oct min kg kg/h
9H20 34276
9H47 27 34595 709 factory off Ceph's on
11H00 73 35570 801 factory off Ceph's on
12H30 90 37022 968 factory on Ceph's off
14H25 115 39184 1128 factory on Ceph's off
15H40 75 40745 1249 factory on Ceph's off
16H00 20 41351 1818 factory on Ceph's on
11-oct
11H10 1150 68667 1425 factory on Ceph's on
12H45 95 71155 1571 factory on Ceph's on
14H25 100 73706 1531 factory on Ceph's on
Make-up water consumption is around 40m3/day, 1.6 to 1.8 m3/h.
The % of condensate returns is 0% if we consider this value.
We have calculated the % condensate return with the information from the Feed tank temperature.
The feed tank had an average temperature of 80°C.
The softened water temp is 25°C.
The condensate average temp is 120°C.
0.4x25+ 0.6x 120= 82
We can estimate that you have between 60 and 65% of condensate return and 35-40% of softened
water.
It seems very low if we consider that you have no direct injection in the product
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 40 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
It will be interesting for you to replace the water flowmeter to follow correctly your % of condensate
return.
Note:
The steam flow meter is only installed on the Ygnis Boiler pipe.
The accuracy is not very good, the distance between the flowmeter and the elbow is not sufficient.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 41 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Steam distribution
Steam is delivered to the different process from the main header.
The steam trap is not installed on a drip leg, the pipe is blocked with dirt and the condensate is not
drained.
We followed the three steam lines in order to analyse all consumers.
From the boiler room, steam is distributed by:
- One line DN 50 at 6 bar to the Laundry
- One line DN 100 at 6 bar to Factory
- One line DN 50 at 6 bar to Ceph’s
You have steam traps without drip legs on the different line to laundry and factory but no draining
points on Ceph’s line.
We have calculated the maximum flow that can be delivered at 6 bar pressure.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 42 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
You can deliver 2000 kg/h of 6 bar steam in the DN80 pipe, with a velocity of 30m/s.
You can deliver 780 kg/h of 6 bar steam in the DN50 pipe, with a velocity of 30m/s.
You can deliver 200 kg/h of 6 bar steam in the DN25 pipe, with a velocity of 30m/s.
Your steam pipes are correctly designed considering the steam flow recorded.
.
Steam consumers
5.1.1 60°C Hot water Tank
For comments on this steam user, see Project 3.
5.1.2 Laundry
The 6 bar line feeds a PRV station protected by a check valve and a drip leg.
None of the ancillaries is insulated.
There is no safety valve after the PRV, you close the manual valve when you don’t use the laundries
equipments.
The TD steam trap is leaking.
This PRV station feeds:
• 2 Dryers, just one in service
• 1 Press iron
None of the ancillaries is insulated
The Press steam trap is leaking.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 43 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
5.1.3 Ceph’s The steam pipe to Ceph’s has a dilatation lira not protected by a drip leg.
The different process fed by this pipe are:
• Munters coil
A PRV station protected by a strainer (installed not correctly, see section Installation Errors).
None of the ancillaries is insulated.
The drain valve before the steam trap was opened.
• Clean steam generator
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 44 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
This exchanger is only used when you have to do a sterilisation after maintenance operation.
There is no drip leg to protect the control valve.
None of the ancillaries is insulated.
• Distiller
The control valve is protected by a strainer (installed not correctly, see section Installation Errors).
None of the ancillaries is insulated.
The process steam trap was in incorrect position, it was leaking.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 45 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
You had a drain valve connected to the body, this valve was opened.
The pressure in the body was low, you flash a part of condensate and don’t evacuate correctly the
condensate.
You have installed it in correct position, but it was always a little leaking.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 46 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
The equipments are protected by 2 separators, one steam trap was leaking.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 47 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
5.1.4 Factory area
A PRV station decreases the pressure from 7 to 5-6 bar.
You changed the PRV valve during our audit, as previous one was failed.
None of the ancillaries is insulated.
The different processes fed by steam are:
• AHU
All steam traps were insulated, which could disturb their operation. Indeed, most of these were Float &
Thermostatic type which contains an air vent opening based on difference in temperature between
saturated steam and non-condensable gases.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 48 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
• Glatt Coating
• Munters dehumidification coils
On soft gelatine Munters coils, most of the steam traps were leaking, you replaced them during our
audit.
• Sirup heat exchanger
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 49 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Not in service.
The line steam trap was cold, the pipe is probably plugged.
• Sirup Tanks
Pipe to sirup Tanks, there is no drip leg before the PR Valves and On-Off solenoid valves.
The steam pipe was cold.
During operation, you drain the condensate to the sewer.
You might put 2 steam traps in parallel, one Bimetallic for start up connected to the sewer, one IB float
connected to the condensate return pipe for continuous operation.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 50 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Purified hot water Generator
The steam trap was installed above the exchanger, not close to the drain valve.
• Double Jacket Tank
This tank is mobile, you connect the steam and condensate pipe when necessary.
There is no drip leg before the steam valve to drain the condensate when the valve is closed.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 51 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
• Hot Water Tank
Steam pipe fed the coil of the 90°C water Tank.
The control is done by a thermostatic valve, and the steam trap technology is thermodynamic.
There is no drip leg to protect the control valve.
The coil is leaking, you increase the pressure in the water loop, so you control actually the Temp
manually.
You closed the manual valve to decrease the steam pressure, but could not drain the condensate.
The water’s temperature was 65°C and not 90°C.
We propose you to replace this tank by a heat exchanger package. We need more information
concerning water flow to design this package.
Condensate return network
Condensate from Ceph’s was drained by a float trap installed in series on the main condensate pipe
DN50.
You installed a pumping trap after this float trap.
The vent of the condensate pump header was modified with a hydraulic pipe.
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 52 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
You maintained the pressure in the condensate pipe and disturbed the correct drainage of the
condensate. After the pump, the condensate pipe was reduced to DN32, which increased back
pressure even further. This has disturbed the operation of the system and created flash steam in the
feedtank.
In the current configuration, the steam trap in series and the pump trap are not necessary. We have
asked you to dismantle the mechanical pump and the float trap, which was done during our audit.
The result was less flash steam at the vent of the feed tank.
You have always small pressure in the pipe due to the reduced section pipe.
Condensate from the factory returns in a condensate tank (see Project 6).
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 53 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
APPENDIX
- Steam flow calculation - Efficiency calculations - Radiation losses calculation - Misassemble - Steam trap survey - Steam Pressure Controlled Heat Exchangers at Low Load
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 54 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Steam flow calculation.
We calculate the steam flow of the different process by velocity of 30m/s in the inlet pipe and energy
calculation
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 55 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Efficiency calculations
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 56 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 57 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Calculation with Optimization ECM 2. The indicate cost are not euro but Egyptian Pound
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 58 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 59 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Calculation with Optimization ECM 2. 100% Time with Ygnis Boiler The indicate cost are not euro but Egyptian Pound
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 60 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Radiation losses calculations
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 61 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 62 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Installation mistakes
Missing drip leg:
In place of ½’’ pipe
Main pipe to Cephs before elbow
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 63 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
In the elbow before control valve
Before dilatation elbow
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 64 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
In the elbow before control valve
In the elbow before control valve
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 65 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
before the manual valve Heat exchanger not in service
In place of ½’’ pipe
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 66 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
In the elbow before control valve
Syrup Tank
No picture
In the elbow before manual valve
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 67 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
In the elbow before manual valve
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 68 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
All steam strainers must be turned by 90°.
Boiler Hose
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 69 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Factory Purified hot water Generator
Old Glatt AHU
ooL Ceph’s Munter
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 70 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Ceph’s Distiller
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 71 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Steam trap survey
There are 47 steam traps installed on your network.
47 steam traps were identified. 11 of the installed traps were out of service. 19 of the traps were failing
(11 leaking, 8 plugged or flooded).
Many steam traps are insulated, we recommend you to dismantle the insulation to increase the
efficiency of the float trap. One thermostatic trap is in the chamber of the trap, and must drain
incondensable, if the trap is insulated, the trap is not open and you don’t drain the air and you reduce
the float TRAP capacity.
The technology are :
Thermodynamic Qty13
Float Trap Qty29
Inverted Pocket Qty4
26 steam traps for process and 20 for line.
List on Excel Chart
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 72 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Steam Pressure Controlled Heat Exchangers at Low L oad
Current situation
Within the steam system, there are several pressure controlled heat exchangers operating at low loads.
Within these heat exchangers, liquids or gasses (air) are heated along with the steam. Most of the time
the desired medium temperature is below 100°C, and the heat exchanger is working at partial load.
Under these conditions, regardless of brand or model, problems may occur due to the physical
properties of the steam.
An audit is only a short visit on site, in which it is impossible to see all operating conditions. Most
problems with heat exchangers only occur at certain conditions. For instance, operation of heat
exchangers for building heating may only be a real problem during the fall and the spring, when partial
loads are typical. Due to the variability of these problems they are often not recognized in time, and can
cause process bottlenecks, loss of production, loss of temperature control and increased maintenance
costs.
Control of steam pressure can be designed in two ways: modulating or on-off. In both cases the control
valves are modulated by the measured temperature of the heated media. Steam pressure controlled
heat exchangers at low loads almost always produce sub-cooled condensate.
Modulating Controls
The steam pressure after a modulating control valve is always lower than the steam pressure in the up
steam lines, unless the system is working at full load which is a rare operating condition.
When heating a product to a temperature below 100ºC, the required steam temperature will often be
close to 100ºC, as the latent heat of the steam is used to transfer the energy as the steam condenses.
Steam temperatures lower than 100ºC, has a pressure below atmospheric pressure. If the steam
pressure after the steam control valve is less than the pressure in the condensate line, there will be no
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 73 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
driving force (pressure differential) available to push the condensate out of the heat exchanger and
move it to the condensate receiver. The condensate will back up in the heat exchanger, and will
become flooded. This situation is often called a “stall situation”. As the condensate backs up in the heat
exchanger, it will exchange sensible heat with the product, where the condensate becomes sub-cooled
(matching the product temperature). The infrared pictures below show the condensate backing up in a
shell and tube heat exchanger as well as a plate and frame heat exchanger, and the resulting
temperature differences in it.
The more a heat exchanger is oversized , the sooner it will operate at a partial load and the more the
condensate will sub-cool.
During a stall condition, the output of a heat exchanger is no longer controlled by the steam pressure
and the resulting amount of steam through the control valve. In fact the output is now continuously
controlled (limited) by the condensate level inside the heat exchanger. A few centimetres change of
condensate level will have a huge impact on the heat output. A pressure change of only 10 centimetres
water column (= 0,01 Bar) on steam inlet or condensate outlet (= back pressure) can be the difference
between 0% and 100% output. In the best case scenario the control system will balance the
steam/product differential. However even the best control system cannot control the back pressure
variations in the condensate return system. Therefore, in most cases the following is observed:
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 74 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Due to the condensate backing up the amount of heated surface in the heat exchanger is reduced, and
the desired set point product temperature cannot be reached. As a reaction to this, the steam control
valve will open, thus providing enough pressure differential to push out the condensate. When this
happens all the heating surface in the heat exchanger is available again causing a sudden rise in the
product temperature. There will be an overshoot in temperature which the controls will try to correct by
closing the steam control valve. This cycle will repeat and control valves will “hunt” searching for
balance. Hunting control valves, and actuators, wear quicker and tend to leak. The most critical aspect
of cycling control valves is that the frequent changes in temperature will cause local material stresses in
the heat exchanger, which over time can cause failures and leaks (especially in stainless steel). In
addition the presence of relatively cold condensate may cause water hammer and corrosion inside the
heat exchanger which can also lead to leaks. These leaks often occur on the outside of the heat
exchanger (gasket failure), where they will be clearly visible. However these leaks can just as easily
occur inside a heat exchanger, thus causing contamination issues and even blockage of heat
exchangers.
Lowering the condensate back pressure will reduce the risk of condensate backing up in the heat
exchanger, which provides two system improvements. First, it will reduce the loss of exchanger
capacity, and second, it reduces the risk of water hammer. Often when condensate is backing up, the
condensate lines are drained to the sewer. This is only a temporary fix and is a great loss of energy and
can raise waste water temperatures above safe limits.
Optimization
A number of solutions have been developed to solve the problems with heat exchangers at low/partial
loads. Finding the most effective and efficient solution would require custom tailored engineering.
Basically there are six methods to remove the condensate from a flooded heat exchanger with steam
pressure control:
• a closed loop pumping trap
• a Posipressure system
• a safety drain trap
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 75 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
• a barometric leg
• change to condensate level control
• a mixing valve on the product side
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 76 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Closed loop pumping trap
A closed loop pumping trap arrangements uses a balancing line to equalize the pressure in the heat
exchanger and the pumping trap. Condensate will drain by gravity toward the pump, and will be pushed
out using steam pressure. The diagram below shows a typical setup:
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 77 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Posipressure system
A Posi-pressure system allows air or nitrogen to push out the condensate as soon as the steam
pressure inside the heat exchanger is less than the back pressure in the condensate system. When
using a Posipressure system, the condensate return system should be able to handle small quantities
of air or Nitrogen. The steam traps applied should be inverted bucket traps, and the condensate
receiver has to be vented. The diagram below shows a typical setup for this arrangement:
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 78 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Safety drain
A safety drain is a second trap that is sized to handle the same load as the primary trap. It is located
above the primary trap and discharges into an open sewer. When there is sufficient differential
pressure across the primary trap to operate normally, condensate drains from the drip point, through
the primary trap, and up to the overhead return line. When the differential pressure is reduced to the
point where the condensate cannot rise to the return, it backs up in the drip leg and enters the safety
drain. The safety drain then discharges the condensate by gravity.
Barometric leg
A barometric leg can be created by moving the steam trap to a lower position. Every meter the trap is
positioned below the heat exchanger will generate 0,1 Bar pressure differential. Reversely, lift of
condensate after the steam trap or back pressure in the condensate return system, will reduce (or even
eliminate) the effect of the created barometric leg. Of course this option will only work if sufficient height
differential is available. A steam temperature of 60°C requires a barometric leg of 8 meters!
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 79 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
Condensate level control
On condensate level controlled heat exchangers full steam pressure is applied on the heat exchanger.
The capacity of the heat exchanger is controlled by changing the level of condensate inside the heat
exchanger. The submerged part of the heat exchanger works as a condensate after cooler.
Condensate from a condensate level controlled heat exchanger is always sub cooled.
Heat exchangers have to be specially designed to work on condensate level control. There should be
sufficient height differential between minimum and maximum condensate level to allow accurate
control. Horizontal heat exchangers cannot be used for condensate level control. Furthermore the heat
exchanger should be able to handle mechanical stress due to local temperature variations, and the heat
exchanger should be able to handle sub-cooled (low pH) condensate. Most plate and frame heat
exchangers are not suitable for condensate level control. Vertical hairpin heat exchangers, with steam
and condensate in the shell and product in the tubes, work best on condensate level control.
Part of the product is exposed to maximum steam pressure and hence maximum steam temperature;
not every product can handle these high temperatures. Caution is advised on applications where the
steam temperature could exceed boiling temperature of the heated product (reboilers on distiller
columns). Due to local high temperatures inside the heat exchanger, the product will very likely start
boiling at these hot spots. The product vapours will implode again as soon as they mix with the colder
product ( cavitation). The result will be similar to water hammering on steam systems, only this time it
occurs on the product side. Both can cause leaks and provide a serious health and safety hazard.
Controlling on condensate level is a slow process. In the event the condensate level control valve (or
controls) fails, or if the controls cannot keep up with sudden load changes, live steam may enter the
condensate return system. During this event, the heat exchanger will work on full capacity. The
pressure in the condensate return system will suddenly increase, which may disturb other processes.
These events will soon be recognized by process operators. Passing live steam into the condensate
return system furthermore represents a serious safety issue. To control this safety risk, a number of
precautions can be applied:
STEAM AND CONDENSATES PRE-AUDIT
P 30432
GLAXOSMITHKLINE
Cairo, Egypt
Date : 23/10/2012
Page 80 of 80
To the attention of Mohamed Kamal Awad and Amr Mohamed Alaa Ibrahim
Established by Eric MONTREER
- A temperature alarm in front of the condensate discharge valve. This alarm closes the steam
inlet in case the condensate temperature exceeds a certain set point.
- A float switch on the shell of the heat exchanger. Low condensate level generates a signal to
close the steam inlet valve.
- Installation of a mechanical steam trap in front of the level control valve. The steam trap opens
for condensate and closes as soon as steam enters the steam trap. Advantage of this solution
is that it will secure operation, however the heat exchanger will work on full capacity.
Another risk using condensate level control, is that the heat exchanger will be fully flooded with
condensate (up to the steam inlet valve), in case there is no demand for heat. This could also induce
water hammering. This can be prevented by the following measures:
- A high condensate level switch closing the steam inlet on too high condensate levels.
- A mechanical steam trap at the highest condensate level. The excess condensate will be
discharged by this steam trap.
Mixing valve on the product side
Instead of controlling the product temperature by modulating the steam pressure, it is also possible to
fix the steam pressure and blend the heated product with cold product. In this case the steam pressure
has to be fixed at a pressure exceeding the condensate back pressure, thus securing that condensate
will be pushed out of the heat exchanger. This (too) high steam pressure will overheat the product. This
overheated product can be cooled down again by blending it with non heated product.
Caution should be taken however, as local overheating however can cause scaling and fouling issues in
heat exchangers. Furthermore the elevated steam pressures will result in elevated condensate
temperatures. As a result more flash steam will be generated, which has to be recovered to maintain
system efficiency. Also this flash steam may require enlargement of condensate return lines in order to
prevent water hammering.