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Western Research
!impartial technical support to every major
oil and gas company in the world !do not sell equipment or license technology !wide exposure to different technologies and
operating procedures
Improved Performance
Key elements
● process evaluation ● process modification ● process monitoring ● process knowledge
Process Evaluation
● data gathering − on-site review of operating data
● stream sampling − using proprietary techniques
● stream analysis − using proprietary techniques
● simulation − using in-house engineering software
● engineering review − operational changes − design changes
Amine (AGE/TGTU) - Case Study ● combined AGE/TGTU absorber ● 40% MDEA strength
Parameter Oct 16 Oct 17 Optimized
H2S in Absorber Outlet(ppm wet) 356 202 126
Emission Reduction (%) 39.4 62.0
Amine (AGE/TGTU) Case Study Results
On-Site ● Sulphur / Amine Experts analysed all gas streams ● recommendation to reduce lean loading from 0.006
to 0.003 mol/mol ● overnight optimisation was conducted and: H2S in the tail gas reduced from 356 to 202 ppm (wet) - a 40% reduction Off-Site Detailed Evaluation ● further optimisation of lean loading, amine strength
(50%), circulation & temperatures ● optimised operating conditions will result in: H2S 126 ppm (wet) in the tail gas - a 62% reduction
Superclaus® - Case Study ● conventional modified-Claus, two catalytic
reactors ● followed by Superclaus® stage ● one year in operation
Test No. Unit Superclaus Outlet Recovery %
Stack Recovery %
1 400 98.24 No sample
2 400 98.14 No Sample
23 400 98.58 98.46
24 400 98.56 98.51
Superclaus® - Case Study
● tuning of bed temperature and oxygen concentration
● relatively low recovery efficiency due to high CS2 in tail gas
Result: ● recovery increased from 98.20 to 98.55 ● 20% reduction in emissions
Superclaus® Catalyst Management ● catalyst ages over time, performance can be
managed by increasing the temperature
Table 4.2-3 - Train 3 Superclaus® Performance Summary Test 2 Test 8 2006 Reactor Temperature Inlet°C Maximum (°C)
215 235
200 220
193 220
Reactor Performance Activity 1 (%) Selectivity 2 (%) Yield 3 (%)
99.5 85 85
55 100 55
97.1 89.8 87.2
As Found 900°C (1650°F) - 8% O2
Step 1 790°C (1455°F) - 7% O2
Step 2 650°C (1200°F) - 6% O2
No Plume!
Incinerator Optimization - Case Study
● tuning of temperature and oxygen concentration
● SO2 mass emission unchanged
Result: ● elimination of visible plume
Important consideration: ● ground level SO2 concentrations !!! ● requires detailed dispersion modelling
Process Modification
● short term process changes − immediate on-site operational changes to improve
performance ● operation recommendations
− detailed process and equipment evaluation − recommendations to improve performance − prioritized recommendations by most effective and least
capital ● process design evaluation
− equipment modifications to improve performance − equipment changes to increase performance − equipment debottlenecking
Sulphur Reliability - Case Studies ● refractory and waste heat boiler failures ● lethal incidents and major downtime
Loss of reaction furnace refractory
Sulphur Reliability - Case Study 1 Results
● root cause analysis, need to look at −original equipment −maintenance and repair procedure −operating history, control scheme and manual
Overheated refractory - loss of containment
Root cause: incorrect control scheme
Reliability - Case Study Results
● tube leak resulted in loss of containment − outlet chamber flange leak due to acid attack
● root cause: poor repair procedure
Filtration - Case Study ● 40% MDEA system ● one absorber, one regenerator ● not able to increase throughput due to foaming ●H2S specification in treated gas not met ● fuel gas sent to flare
before after
Case Study Results
● Filtration Experts performed on-site evaluation and performance testing of inlet separation
● root cause of the problem was deficient system design and poor separation efficiency
● new inlet separator design and installation As a result: ● foaming stopped
− capacity increase to near design limit − savings: USD 5.3 million/year in gas/liquids alone − H2S specification in the treated gas met, resulting in
USD 150 000/day being processed and not going to flare
Process Monitoring
● regular plant performance testing − allows for benchmarking performance
● maintenance prioritization − determine need for amine or catalyst
replacement ● process trending
− determine catalyst performance ● efficiency and optimization monitor
− meet regulatory permit requirements
Incinerator Emission - Case Study ● new 400 ppmv CO emission limit ● current incinerators were not in compliance
Incinerator Emission - Case Study
● concluded that existing incinerators are capable of meeting 400 ppmv CO − requires an increase in temperature − tuning of oxygen concentration
Result: ● eliminated capital cost project and
significant down-time
Incinerator Emission - Case Study Down-side: ● increase in fuel gas increases operating cost
(+25%) ● upstream CO conversion investigated
− requires plot space and investment − significant reduction in fuel gas consumption (>50%)
Important consideration: ● ground level SO2 concentrations !!! ● requires detailed dispersion modelling
Process Knowledge
● education −engineer and operator training
● experience −ensure operator ownership
● thermodynamics − know the chemistry
● kinetics − know the process limitations
Process Knowledge - Case Study ● Sulphur Experts on site for training ● sooting from main burner Result: ● high pressure drop across the first reactor Training and support provided the comfort to: ● implement a sulphur wash ● restore unit capacity without down-time
Technical Service Program Key elements ● emergency priority assistance (hot-line) ● data review and trending ● set up a monitoring program with key performance
indicators ● conduct a full visual inspection of all SRU equipment
(during a turnaround) ● regular on-site meetings to discuss unit performance
and operation ● periodic on-site performance testing and optimization
(annually) ● in-house training
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