Implementation of Best Practices for
Improvements in Reformer
Performance and Reliability
Ya,a imernationai operates manu/acluring/acilities globally which include twelve operating
ammonia plants. Ya,a has developed a global best practice document which outlines the important
parameters to be used in managing the reform ers within these plants for efficient, safe, and reliable
operation. Quest Integrity has assisted Yara in the implementation of elements o/Steam Reformer
Best Practice to have Q l..'onsistent approach to the strategic management o/their sleam reformers
worldwide.
This paper discusses the best practice elements of the Yara Reformer Catalyst Tube Lifecycle
Management and the management process used to implement these objectives. Included in the paper
are examples offacility training performed for plant operators and reliability groups, implementation
of reformer tube temperature management, and performance and reliability of monitoring performed
for steam reformers. The paper will conclude with the short and long-term benefits to Yara as realized
through tlris implementation.
Giuseppe Franceschini
Process Owner Inspection, Yara International
Giuseppe.Franceschini@yara.com
James R. Widrig
Manager, Advanced Engineering, Quest Integrity, LLC
J .Widrig@Questlntegrity.com
fonn and could be improved. The number and
frequency of tube failures occurring at some of
the sites was indicative of the improvement opportunity. More efficient, safe and reliable operation of these assets was viewed as criti cal to the
company's success and reason for the focus on a
spec ific best practice. Quest Integrity was recognized by Yara for their reliability expertise in the
ammonia and broader syngas industry, specific
servi ce and technology for reformers, and as a
Introduction
T
he implementation of a best practice fo r
the life cycle management of reformer
tubes was an enterpri se-wide goal for
Yara International. Yara management
recognized that they operated a large number of
steam-methane reformers (refonners) globally
and the management of these assets was not uni-
2015
115
AMMONIA TECHNICAL MANUAL
provider of world class products and services.
Together, Yara and Quest Integrity developed a
project scope and a plan to provide training for
operators and reliability groups, implementation
of tube temperature management, and reforme r
performance and reliability surveys of this global
set of assets. These best practice program elements of Reformer Care were implemented for
all of the Yara International reformer assets during the time span ofmid-20l3 to early 20 15.
Basic Elements of Yara Catalyst
Tubes Management Best Practice
Reformer catalyst tube reliability involves the
whole Production Facility Organization (Inspection, Production, and Maintenance) in order to
systematically address all the phases of the tube
life-cycle. Yara' s approach to the life cycle management of reformer tubes, as documented in the
best practice document Yara BP63 (BP63), involves training of personnel at both an operating
and management level to ensure that they have
an understanding of materials, common damage
mechanisms, and inspection and monitoring
techniques. This knowledge is used to evaluate
manufacturing or fabrication deficiencies, deterioration or damage in service and the life cycle effects of operation deviations. The goal is to make
optimum use of the refonuer tubes (plus the pigtai ls and headers) over the expected li fe and
avoid untime ly and costly premature failures.
Overview of Yara Reformers
Yara has 12 operating ammonia plants located
worldwide. These ammonia plants and reformers
vary in process technology, reformer design, capacity, and age as well as production efficiency
and reliabi lity. The reformers are a combination
of Top-Fired, Side-Fired and Terrace Wall designs (Table I). The oldest reformer in the system is the Yara Le Havre, France, reformer
commissioned in 1967 and the newest reformer
is the Yara Tertre, Belgium, reformer commissioned/rebuilt in 20 I0 following a firebox explosion. There are a total of 3, 180 tubes in these 12
reformers. The oldest tubes were installed in
1977 in Porsgrunn, Norway, and Ferrara, Italy.
The average age of the installed reformer tubes is
around 20 years.
R. Io ......
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1987
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Specific steps are defined and accomplished to
manage reformer tubes over each operating cycle
fo r the reformer. The operating cycle is defined
as the period of time between two consecutive
turnarounds, typically 4 or 5 years (Figure I).
These asset management steps include an initial
survey of the reformer conditions during operation soon after start-up, continuing visual inspection and tube temperature surveys on a regular
basis, life assessment of reformer tubes and
components prior to a scheduled turnaround, inspection and assessment during a turnarounds,
and careful observation and execution of start-up
and commissioning (Table 2). The cycle of the
activities is then repeated.
1.Operlltion: Sta rt-up
Acfivilies: " 2
".
5. T/A e.>tecution
Acfivilies: B, 9, 10, 11, 12, 13, 14
,~
'"
Modified
'"
Modified
'"
... Operation: TlA preparation
(typica lly 1 yearbelore TIA)
Acfiviries: 6, 7
".
'"
""
'"
Table I. OvervIew ofYara reform ers
Terrace
Wall
AMMONIA TECHNICAL MANUAL
2. Operation: lew weeks after
start-up
Activities: 14
J. Operation: NNormal"
Acfiviries: 5
Figure I. Catalyst tube operating cycle
Modified
116
2015
Pha5e
Activity
Respon5ible
1.0peratioo:
Start-up
1. Regular and frequent vlSlJallnspeclions of the tube to avoid over-flring during start-up
2. If the loca l firing is reduced (to bealty decrease the tube temperature) it is advisable not
increasing the genera l level of fi ring in order to avoid the "wind-6own" effect
1. 2 First Line Maintenance
(operationa l personnel. Production)
3. On-line reformer survey few weeks after TIA
a. Physical condition of the bume.-s
b. Bowing evidence and colour variation between the rerom-tubes
c. RefractO!)' condition
d. Reformer operaUng parameters as compared to the design basis
e. Maximum allowable temperature (MAT) calculation
f. Tube metal temperature meaSlJrements Vs MAT
g. Temperature spread between reformer tubes
h. Carbon formation margin
Monrtoring catalyst performa nce· activity and pressure drop are within expectations for
a catalyst of a given age
j . Combusbon survey
2. Operation:
few weeks after
start-up
3, 4. First Line Maintenance
(operationa l personnel. Production )"
Extemal Specialized Contractor
,
4. Fumace balancing
5. On-line inspection and monitoring:
a. Visua l inspecUon (every sh ift) ·
L Sign ifICant colour variations or presence of hot bands
ii
iii.
3. Operation·
"Normal"
"
"
Sa. First Line Maintenence
Tubes away from each other, tube bowing
SignifICant tube bent resuHing in a horizontal displacement
Burner. evidence of backfiring. fou ling or deposit
Refractory damage
(operationa l personnel , Production)
5b. First Line Maintenance
(operationa l personnel. Production)
b. Tube temperature measurement with an optical pyrometer (every month)
5c Inspection
c. Tube temperature analysis and operation recommendation development (every mont h)
L Temperature spread among the tubes Vs maximum recommended spread (50"C)
ii
Maximum skin metal temperature values Vs MAT
6. Preliminary tube residual me assessment. damage ctass projection. prel iminary lubes retirement planning (preliminary estimation of the number of tubes 10 be replaced at next
TIA)
4. Operation:
TIA preparation
(typOcally 1 year
before TIA)
7. Tube purchasing : Quality Control
6.7. Inspection and Maintenance
a. Accurate Manufacturer selection
b. Certificate and NOT report revKiw
c_Workshop visrt
d.IO Lase~ baseline meaSlJrement
8 _TIA catalyst tube inspection·
8 _Maintenance. Inspection +
Extemal SpecialiZed Contractor
a.lf catalyst is replaced (10 access) 10 Laser Profile + EC
b _11 catalyst is not replaced. (00 access): 00 Laser Profile + EC
9.
Reformer tubes cond ition assessment: coupling inspection and residua l life calculation ,
damage class projection at the next operating period, applying retirement criteria
10. Reporting reformer tubes condition assessment results: reformer tubes creep damage
class mapping
5 _TIA execution
"
"
"
Tubes replacement according
to assessment results at point 10 above
Metallurgical analysis of retired tube samples
Cil-l<Il~1 <;hil-rging:
instrument
pressv~
to oonfirm the creep damage class
QrQP meil-"I,"ement Qf Ci!-lil-I~t in
e~
t\lbe with PQrtil-ble
14 Burners: visuil-I inspection. maintenance il-nd testing beforE! sl<lrt-up to avoid Ioc<II overhealing due to burners malfunctioning
9. Inspection ..
Extemal Specialized Contractor
10_Inspection +
Extemal Specialized Contractor
"
Maintenanoe
12: Inspection +
Extemal Specialized Contractor
13: First Line Maintenance
(operationa l personnel. Production) +
Extemal Specialized Contractor
14. Maintenance
Table 2. Catalyst tubes management actlvlfles
2015
117
AMMONIA TECHNICAL MANUAL
During the 201 3 survey, a Cost-Benefit analysis
was performed to estimate the potential benefit
of a full and unifonn implementation of BP63.
Thi s analysis was executed according to API 581
[2] ca lcu lating the tube probabi lity of failure due
to creep in the follo wing 2 conditions:
Reformer Survey and Cost-Benefit
Analysis - Why Yara asked for
assistance for its BP63
implementation
In 20 13, two years after the deve lopment of
BP63, Yara performed a survey on all of the reformer assets. From the survey, Yara recognized
that the management of these assets was not unifonn and could be improved (Table 3). The catalyst tubes failure hi story data included in the survey detennined that an average of 8 tube failures
every 3 years were occurring (not inc luding tube
fai lures due to incidents/trips), It was also clear
that the a reas with the greatest room for improvement were the temperature monitoring progra m and the residual life assessment of the catalyst tubes.
•
•
Full impl ementation of Yara BP63:
" hi ghly effective" inspecti on, monitoring
and assessment program
2013 Basis or actual situation: "fairly effective" inspection, monitoring and assessment program
The result of the analysis showed a significant
potentia l benefit (Table 4).
Number of fa ilures il J yeiltS {cillcuJarion ilccot;(/ing 10 AP1581 : comlf'mH(
illhe ilClUillslluarion, by retexmer survey)
CalOJlaled failulefreQl.Jl!ncy. lf2 [n'oflailures /(years • n' of tubes )]
Full implemenla~c:noIYara SP63 (high ty ellective inspection
ITKInnoringandassessmel1)
•
5.84E.()4
CalOJlaled failureheQUency. 1f1(n' offailures /{ye ars 'n' oltubes)]
2013, Actual situ abon (fairly effective inspection, monitorl1g and
assessment)
2.77E'()3
Tolal number of tubes
3180
EsUmaled number of tubes with ITKIre than 25 years 01 service, n
,5<
TIme period forthe Cost.senelit analysis,t [Years]
3
Tube failures in 3years, F2 ,,112' t ' n
Full implemenlatic:noIYaraSP63
Tube failures in 3years, Fl - fll' t' n
2013,Actual situation
Tube failures lHferenee in 3yea rs , F2-FI
U
7.'
6.3
Cos/.Bener-/f analysis rex 12 Ammooia Unirs
Economic COnSeQIIJence 01' Failure, COF [I(E I Failure)
Inspection, MoMoring,Assessment Cost Estimation for 12
Ammonia Units in3years, C2 [k€)
1000
1434
Full implemenlatic:noI YaraBP63
Inspection, Monnoring,Assessment Cost Estimation for 12
Ammon ia Units in3years , CI [k€)
360
2013,Actual situation
Cost 2"· (F2'COF + C2) [k€J
Full implementatiooolYaraBP63
Cost 1 ". (FI'COF" CI ) [k€I
-il260
2013,Actual situation
Benefil in J years, (CosI2
·3134
COSlf) {I!€}
5126
Annual bener-If, (Cosr 2 - Cosr 1)1 J {Iff}
1708
Table 4. BP63 lmplementatron: Cost-Benefit
Table 3. Yara reformer survey result
AMMON IA TEC HNICAL MANUAL
118
2015
Based upon the 2013 reformer survey and the estimated potential benefit, Yara selected Quest Integrity to assist with the global implementation
of BP63 through a specialized program of "Reformer Care" with the ultimate objective to reduce the number and frequency of catalyst tube
failures.
and identity and recommend performance
and reliability strategies for improvement
These elements were chosen by Yara to close the
gaps (against BP63) identified during the 2013
reformer survey, with particular focus on Maxi mum Allowable Temperature (MAT) determination, temperature monitoring and residual life assessment of the catalyst tubes.
"Reformer Care"
"Reformer Care" Implementation
Example
Quest Integrity's "Reformer Care" includes data
analysis, remaining life assessment, and engineering solutions. These services can be applied
individually to address a specific issue or may be
grouped to together to apply to a wide-range of
integrity issues.
The implementation of the "Reformer Care" services was accomplished according to a schedule
developed by Yara. The schedule was based upon Yara's evaluation of several factors including
the turnaround timing of the reformers, histOIY of
operational and reliability issues, age of reformer
tubes and planned replacements, and availability
of site personnel.
These services offer a unique solution to attain
operational safety and reliability goals, enable
proactive decision making, eliminate premature
harvesting of reformer tubes, improve knowledge
of turnaround requirements and reduces costs
with proper planning, increase the understanding
of reformer operation and limitations, and addresses all reformer systems.
The Yara Global Inspection Group had the overall responsibility for coordinating on-site training
activities and coordination of information about
the reformers to Quest Integrity ahead of the onsite work. Information exchanged included operating and design information, inspection results,
and fai lure and replacement history. This information was used to develop specific training materials for each of the reformers, provide background information for evaluation of the
reformers, and to customize the temperature correction software application for each reformer.
Site work and training was completed in 4-5 days
per reformer.
Yara selected a sub-set of these "Reformer Care"
serv ices or program elements to assist with their
global implementation of BP63. This set provided Yara with a specialized program of "Reformer
Care" to assist with the strategic management of
the twelve reformers located in eight production
complexes around the globe. These key elements
included:
•
•
•
•
•
2015
Training for operators on visual inspection of reformers including tubes conditions, burner operation, and general condition
Training for operators on tube temperature measurement practices
Implementation of reformer tube temperature correction procedures
Recommendations for maximum allowable tube metal temperatures
Reformer Performance Monitoring to
evaluate the current condition in service
Training
The on-site training for Yara personnel was accomp lished in both a classroom and field environment. Typical training attendance was 10-20
people and a mixture of operation, reliability, and
inspection personnel. Quest Integrity senior engineers delivered the training, performed equipment field surveys, demonstrations and practical
application of methods presented in the cl assroom. The training classroom and field applica-
119
AMMONIA TECHNICAL MANUAL
tion portions of the work were accomplished in
2-days and split between reformer performance
monitoring and reformer tube temperature measurement and corrections.
common reformer tube fai lures. This training included normal and abnormal tube conditions,
bowed tubes, hot spots, bulges, cold tubes, and
conditions due to catalyst damage and poisoning.
Training specific to burners in operation was included to address burner characteristics and design, correct ope ration of the burner, adjustments, maintenance, and troubleshooting.
Practical training on tube and reformer visual inspection during operator rounds was discussed in
the classroom and then practiced in the field by
participants using specifically prepared check list
(Figure 2).
Reformer Performance Monitoring
The topics covered in the training included background information on reformer reliability management, recognition and troubleshooting of reformer performance issues, reformer tube
damage mechanisms and inspection, fitness-forservice and remaining life of reformer tubes, and
how to recognize, troubleshoot and prevent
A
Q/tJ:!:::;,;::..:::::::
MONITORING CHECKLIST
REFORMER PERFORMANCE
FIRE BOX INSPECTION
TO BE PERFORMED EVERY SHIFT
TO BE PERFORMED EVERY SHIFT
TI\RGET
...cTUAL
c::::J c::::::J
c::::::J c::::::J
c::::J c:::::::J
c::::J c:::::::J
c::::J c:::::::J
c::::J c::::::J
c::::J c::::::J
c::::J c:::::::J
c::::J c::::::J
DRAFT
O2ICO/NOX
BRIOGEWALL T EMPERATURE
STACK TE MPERATURE
FUEL PRESSURE
PILOT FUEL PRESSURE
PREHEAT AIR TEMPERATURE
PROCESS INIOUT TE MPERATURE
o
o
o
o
o
o
o
o
o
STEAM TO CARBON RATIO
RADIANT SECTION
TUBE BULGING. BOWING. HOTSPOTS
TUBE COlOR
TUBE EXTERNAL SCALING
CATALYST ISSUES
REFRACTORY COLOR
FLOOR REFRACTORY
WALL REFRACTORY
TUNNEL REFRACTORY
ROOF REFRACTORY
BURNER INSPECTION
TO BE PERFORMED EVERY SHIFT
T"mparal""
BURt£RNO.
Color Guida
. -•
UNSTABLE FLAME
~~
•
_
_ _ _ _ BAD FLAME PATIERN
(1"-0_ ....,..•_ ....)
_ _ _ _ PLUGGED TIPS
_ _ _ _ COOL BURNER TILE
•
_ _ _ _ PILOT TIP NOT GLOWING
0
-_.
0
:,\'::f 0
r,:=:", 0
......... RUI
.;oo.,)OOf
•
_ _ _ _ AIR REGISTER STUCK
IN/OUT PIGTAILS
TUBE HANGER/SPRINGS
CONVECTION/DUCTS
Io/FD FANS
~...,
TRAMP AIR
'- - '
TUBE PENETRATIONS
SIGHT PORTS FUNCTIONAL (SEA L)
EXPLOSION DOORS, FLANGES,
HOLES, LEAKING AIR IN BOX
0
0
~"F 0
. ="_"'t'
PILOT AIR NOT WORKING
EXTERNAl
OR NOT WORKING
_ _ _ _ AIR REGISTER OPEN
WHILE BURNER OFF
_ _ _ _ FUEL VALVE PINCHED
Figure 2. Tube and reformer visual inspection check list
AMMONIA TECHNICAL MANUAL
120
2015
required to obtain consistent temperature measurements. The classroom training was followed
by practical application of the techniques to gain
familiarity and a level of proficiency with the IR
measurement instruments. Temperatures recorded in the field were then corrected through
demonstration and practical experience with
Quest Integrity's CorrectIR™ software application.
Reformer Tube Temperature Management
Accurate measurement of reformer tube-skin
temperatures is a crucial input to a tube life prediction model (not directly based upon measured
creep damage) and is also critical in optimizing
productivity and ensuring optimum reformer operation. Radiation thermometry is a practicable
and reliable method for determining tube-skin
temperatures in reformers provided certain
measurement corrective practices are used. Radiation thermometry in reformers is prone to a
number of errors arising principally from the effects of tube emissivity, reflected radiation and
flue gas (Figure 3). Radiation thermometer readings and thermal images must have corrections
applied in order to obtain the tme tube-skin temperatures. These corrections depend in a complex
way on the geometry of the reformer, the temperature distribution of objects surrounding any
individual tube, and the location of that tube in
the reformer. The corrections also depend on the
operating characteristics of the radiation thermometer or thermal imager used to make the
measurements.
~
r
"T
"...,
Temperature Correction - CorrectlRTM
As an element of the Reformer Care implementation, Yara implemented an lR temperature correction program to establish the actual reformer
tube metal temperatures. In order to determine
the true tube temperatures, corrections must be
made to the thermometer readings based on the
geometry of the furnace, the emissivity of the
tube material, atmospheric effects, and
knowledge of the operating characteristics of the
thennometer itself. The correction of refonner
radiance temperature readings (measured without
correction) to corrected temperatures is accomplished using Quest Integrity's CorrectIR™
software (Figure 4) and method. The methodology and software is based upon the work of Dr.
Peter Saunders. CorrectIR™ accomplishes:
,
1. Corrects radiance measurements for calibration, size of source effect, flue gas
emissions and other instrument and environmental errors
2. Calculates the uncertainty associated with
individual factors
3. Calculates the effective background temperature taking into account rigorous geometry for each tube
4. Calculates the Tube Corrected "true" tube
temperature and the total uncertainty
~~.. ···::::'·········· 1
~...........
.. . . . . . . . I
Figure 3. Radiation thermometry errors: effects
o/tube emissivity, reflected radiation and flue
gas
The second day of classroom and field training
was dedicated to the Infrared Radiation (IR)
temperature measurement theory and techniques
for reformer tubes. The classroom training discussed the application of IR pyrometers and imaging cameras for monitoring reformer tube temperatures along with the operator techniques
2015
A sample output of the temperature corrections
performed using CorrectIR™ is shown in Figure
4. Tubes are referenced by the Tube Row, Tube
Number, Height (location of the temperature
measurement point from the reformer floor), and
Sight Door from which the temperature was
measured. The Tube Reading is the uncorrected
121
AMMONIA TECHNICAL MANUAL
temperature measured by the IR instrument. CorrectIR ™ performs the calculation of the Tube
Corrected "true" temperature and the total uncertainty for the "true" temperature.
Implementation o f the CorrectLR™ across the
twelve (12) reformers in the Yara system is a key
reliability element to sustainin g reformer tube
of the
assets.
life
and
optimization
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Figure 4. Results of Temperature Correction with Quest Integrity's CorreclfRTM software
stances when compared to operating temperature
limits, these corrected "true" temperatures would
allow for increase firing and ammonia production currently.
Baseline Reformer Tube lR Survey and T ube
Wall Temperature Limits
As an element of Reformer Care, Quest Integrity
completed reformer tube temperatures surveys of
each of the Yara refonners. These surveys were
conducted using IR Imaging Cameras and in
some cases IR pyrometers.
Quest Integrity also provided recommended
TWT limits (Maximum Allowabl e Temperature,
MAT) for each of the Yara reformers. Quest Integrity has developed a unique creep material
model for HP Alloys that accounts for material
aging and creep strain rate with respect to stress,
temperature and time. This proprietary creep materia l model is called LifeQuest™ Refonner.
LifeQuest™ Refonner was used to defi.ne Reliable and Safe tube metal temperature operating
The surveys provided Yara with a baseline survey of tube metal temperatures which were corrected using CorrcctIR™. The corrected tube
wall temperatures (TWT) were lower than the
measured radiance temperatures. In many in-
AMMONIA TECHNICAL MANUAL
122
2015
limits for the Yara reformers. The main difference between the original design life estimates
provided by the tube manufacturer or the furnace
designer and the Quest Integrity service life estimate is that for the original design the tubes are
assumed to have retained their original mean or
lower bound as manufactured creep properties
whereas the Quest Integrity model takes into account that the creep properties will progressively
degrade (Figure 5). This information was also
provided as a creep rupture life curve for each reformer.
-
er in operation to assist with balancing the refonner firing and to deliver a reliability strategy
to ensure the safe and reliable long term operation of the reformers. The survey and reliability
strategy included the following essential elements to achieve optimum performance and reliability of the reformers.
1.
2.
3.
4.
5.
6.
7.
HPNb
- HP micro
-
Lower bound
Safety and Environmental
Operating Performance
Reliability Issues
Reformer Tube Condition
Reformer Mechanical Condition
Burner Mechanical Condition
Recommended Corrective Actions for the
Reformers
eJ(·service
... As cast
•
The issues found during the survey (examples are
shown in the figures from 6 to 12) as well as other industry best practices are were addressed by a
set of corrective actions. Principled execution
towards accomplishing these strategic actions
will lead to a higher level of performance and reliability with respect to the reformer.
Ex-service
LMP Parameter
Figure 5. As Cast and Aged Reformer Tube
Material Properties
The creep rupture life curve for the reformer
tubes are used to assess the life impact from
changes in operating conditions. With a corrected
tube metal temperature (plus uncertainty) value
above the Safe limit, the creep rupture life could
potentially be extremely short resulting in tube
failure during the operating period.
Finally, during a reformer shutdown, the actual
consumed creep life may be measured and calculated by utilizing Quest Integrity's proprietary
inspection tools, LOTIS® and MANTIS™ and
the Level 3 LifeQuest™ Reformer assessment
program.
Figure 6. fara Sluiskil H50J reformer: external
scale on upper tubes
Performance and Reliability Monitoring
Quest Integrity perfonned a Reformer survey to
evaluate each of the Yara reformers. The primary
objective of the work was to observe the reform-
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Figure 9. Yara Ferrara B201 reformer: bowed
tubes; uneven tube colour; flame impingement on
tubes; tramp air entering/rom burners out-of
service with air registers open
Figure 7. Yara Sluiskil H501 reformer: tube appearance as "Hot" due to external scale
Figure
Yara Ferrara
out 0/service with both primary and secondary
air register open causing tramp air
Figure 8. fara Tertre BIOI reformer: flame pattern with baking soda test
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Reformer catalyst tube reliability involves the
whole Production Facility Organization (Inspection, Production, and Maintenance) to systematica lly address all the phases of the tube life-cycle.
Each phase of the tube li fe -cycle includes several
specialist activities which are described in detail
in Yara Best Practice document BP63. Together,
and only if properly executed, a ll these activities
reduce the probability of failure of catalyst tubes
with a positive impact on plant reliability.
flashback
Although is too early to evaluate the real benefit
(reduction of tube fai lure frequency) of BP63
implementation through the "Reformer Care"
program, one significant result has already been
achieved: operation, reliabili ty~ inspection and
management personnel have now a clear understanding of the service related tube damage
mechanisms, of the effects of excursions from
design conditions, and, finally, of the monitoring
and inspection techniques that have to be applied
in order to avoid premature tube failures.
Proper implementation with a structured approach, as described in Yara BP63, requires specialised technical support and personnel training.
For this reason Yara selected Quest Integrity to
develop together a program of "'Reformer Care"
to assist with the strategic management of the
twelve Yara reformers.
Figure J2. Yara Ferrara B201 reformer: thermal
image ofexternal hot spot at edge of sight door
The full set of Quest Integrity Group "Reformer
Care" services can be applied individually to address a specific issue or may be grouped to together to apply to a wide-range of integrity issues. Yara selected a sub-set of these "Reformer
Care" services or program elements to specifically assist with their global implementation of Yara
BP63.
Conclusions
References
[1 ] Yara Best Practice BP63, Life-cycle
management of reformer catalyst tubes
(Yarn Internal Document)
[2] API Publication 581 First Edition, May
Quest Integrity Group and Yara International
worked together to deliver a set of "Reformer
Care" services to Yara's Production Facilities.
The overall objective was to reduce the number
and frequency of catalyst tube failures.
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