Analyzer Diagnostics for confident operations SIVAKUMAR SENIOR MANAGER – ANALYTICAL BUSINESS YOKOGAWA SINGAPORE
Analyzer Diagnostics for confident operationsSIVAKUMARSENIOR MANAGER – ANALYTICAL BUSINESSYOKOGAWA SINGAPORE
FCG Singapore Seminar | 10 June 2016
What is an Analyzer ?
• Instruments for determining the qualitative and quantitative composition of gas/ Liquid mixtures.
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The Status of instrumentation engineers is they are not aware what the analyzer is for ? There is lack of knowledgeable people in Analytical field !
The measuring component, its range & the reading severity is mostly determined by the plant licensors
Challenges for Refineries ?
The challenge of modern refineries in the ever growing global competition is to increase their refining margin and by that their profit. Nowadays, global competition, forces refineries to maximize process intensification and process optimization, which are required key stones to increase the refining margins and by that the profit of the entire refinery.
It all starts from the crude oil and ends with final distillates and blends. Optimization of the entire refinery production chain is a major task and starts with enhancing the efficiency of each of the following interdependent processes:
How importance an Analyzer is in a plant & why ?
FCG Singapore Seminar | 10 June 2016
Different Analyzer MeasurementsLiquid
pHConductivityDissolved OxygenOxygen demandDensityChlorineTurbidity
GasOxygenCO, NOX, SO2, CO2, THCDensityPMHydrogen & H2SPhysical properties like
cloud point, pour point, Flash Point, Simulated distillation
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FCG Singapore Seminar | 10 June 2016 5
The three R's of analyzer selection: • Reliability - The analyzer must be highly reliable so it will
maintain a service factor in excess of 95%.
• Repeatability - The output of the equipment must be repeatable for a given input. It need not be accurate (though of course this is desirable) but it must always give the same numeric output for a given calibration or process sample.
• Return - Every analyzer system installation must have an economic return or justification. If it is not used for some form of continuous monitoring or control the unit will not get the attention it receives to remain in operation at the required service factors to be considered reliable.
What is Diagnostics & its relation to Analyzers ?
• To determine an Analyzer is working OK or not depends on how accurately it is calibrated & how accurate is the calibration solution or gas ?
• There should be a way to inform the technician that the calibration result is out of tolerance limits
•• Most of the analyzers working principle depends
on sample flow/ pressure / temperature & so it needs to be continuously monitored
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What happens if there are no Diagnostics ?
• The technician will not be aware whether the reading the analyzer displays is correct
• The frequency of calibration/ validation depends on whether the analyzer functioning is within the tolerance limit which can be ascertained only by diagnostics features
• Wastage of buffer solutions or calibration gases
• Proper closed loop control will not be possible
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pH Response Check with Chemical Cleaning
0
4.5
7
pH
tH
Good Sensor
Aged Sensor
tRtW
Time
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Meas Wash Meas
pH electrode broken, reading always 7 +/‐ 1 unit (ASPOT/SLOPE)
Short circuit in wiring.
Moisture in cable, connector, connection box or electronics.
Wrong wiring
Customer complaints
My sensor does not respond to changes
Most of these problems will be recognized by sensor diagnostic functions.
SMART SENSORS
Et
E1 E3 E2E5 E4
Input 2
Input 1
LiquidEarth
Et
E1 E3 E2E5 E4
Input 2
Input 1
LiquidEarth
No Flow
Increase in Impedance
Polluted / Dirty Reference JunctionEt
E1 E3 E2E5 E4
Input 2
Input 1
LiquidEarth
Et
E1 E3 E2E5 E4
Input 2
Input 1
LiquidEarth
ImpedancDecreases
Glass Sensor Broken / CrackedHigh Impedance
Liquid Earth Not Connected
Diagnostics – ImpedanceWash cycle can be started automatically
E5.2
E4.1E5.1
E5.2
Why customer specification ask for digital sensor technology ?
• Customer trends – Easy maintenance and service– cost reduction of cable distribution– Reliability– Less Knowledge of maintenance staff to interpret Analog signals
• Functionality point of view– Optimizing process control, simplifying maintenance
– Reducing configuration time by decreasing manual data entry
– Laboratory calibration is automatically uploaded in Field instrumentation
Proprietary info goes here…Page.12
Dissolved oxygen sensor diagnostics
Example - SENCOM PC Software SPS24
Simple Calibration and Process Setup
Same Easy Calibration Procedure
Sensor Diagnostics– Use calibration results to perform in‐depth analysis
of each sensor
Comprehensive Database
Information Protection
various data export possibilities – to guarantee protection of sensor history information
Nowadays nobody wants display at the field, Sensors are directly connected , Configurable using RS485 thru PC or MODBUS RTU thru process control systems
FCG Singapore Seminar | 10 June 2016
Virtual Tech Diagnostics Software
Peak DataRetention TimePeak HeightPeak SeparationTailing CoefficientBase Level at Gate OnNoise Level at Gate OnS/N at Gate On
Valve DataNumber of operations
Detector DataOperation Time
Oven Performance DataMax Temp in each analysisMin Temp in each analysis
Monitor & Analyze
• Parameters Over Thresholds• Data For Analysis
Pack & Report
Redundant Ethernet
Maint. Shop PC
PCAS GC Workstation
• To Maintenance Shop PC• Corporate GC Support Center
Email Notification Option
HART Features for Analyzers
“Device description (DD)” has parameter information of device.Describe parameter name, relation between parameters, menu tree structure and method by using “Device Description Language (DDL)”.The source code of DDL complied to binary file and distribute to host venders and also to users.
FeaturesNo need to upload menu and parameter information from device.DD supported host can treat multiple venders and devices.
DDsDDs
DDs
HART, Profibus or Foundation Fieldbus?Which bus system is best for my analyser?
Basically the answer is a known fact and depends on chosen DCS system architecture. Analyser have to follow these decision
• Where is HART best?In brownfield plants based on 4‐ 20 mA technology
• PROs ‐ Configuration in workshop via HART‐Tool ‐ Remote access via HART‐Tool for maintenance purpose
• CONs ‐ No use two way communication for process control
• Where are Fieldbuses best?In greenfield plants, because here it is easier to set up infrastructure of two way communication. This allows to use all device data process control and maintenance purpose
• Profibus PA is stronger in Europe and first designed for Factory Automation
• FF is stronger in America and Asia and especially designed for Process Automation
The diversity of these three protocols, gave customer to find best opportunity for his process, because most of analysers support all three.