Redundant Integrated Turbomachinery Control for a Refinery Cryogenic Unit

Size: px

Start display at page:

Download "Redundant Integrated Turbomachinery Control for a Refinery Cryogenic Unit"

Ruby Gaines
5 years ago
Views:

2 2 Presentation Highlights Common Integrated Redundant ControlLogix system for ESD Process Control Turbomachinery Control Benefits realized by using PlantPAx concept Advanced ECT Turbomachinery Control System Better lifecycle management using common spares Reduced maintenance costs No specialists required to maintain blackbox systems Integrated PlantPAx systems provides high value to customers

3 3 Agenda ECT Company Description Cryogenic Process & Plant Layout Project Description & Requirements PlantPAx System Details Benefits and Conclusions

ECT Background Specializes in design and manufacture of advanced control systems for rotating machinery and other high energy consuming assets Gas Compressor Networks Steam & Gas Turbines and

5 ECT Background Specializes in design and manufacture of advanced control systems for rotating machinery and other high energy consuming assets Gas Compressor Networks Steam & Gas Turbines and Turboexpanders Plant Air Systems Centrifuges Chillers ISO 9001:2008 Certified 300 years of combined experience in all aspects of turbomachinery control Application engineering, site survey, consulting, design, simulation, project engineering and site installation & commissioning

ECT Markets Oil and Gas Upstream, midstream downstream

complexes Gas Plants and LNG Plants Industrial /

Full plant controls Copyright 2010 Rockwell Automation, Inc.

6 ECT Markets Oil and Gas Upstream, midstream downstream Offshore platforms and FPSOs Refineries and petrochemical complexes Gas Plants and LNG Plants Industrial / Manufacturing Compressed Air Systems Biofuels Centrifuges Full plant controls Copyright 2010 Rockwell Automation, Inc. All rights reserved Copyright 2012 Rockwell Automation, Inc. All rights reserved.

ECT Mission Deliver VALUE through customer-driven control solutions for processes and machinery to Maximize Production Energy efficiency Reliability and availability Minimize Down time

7 ECT Mission Deliver VALUE through customer-driven control solutions for processes and machinery to Maximize Production Energy efficiency Reliability and availability Minimize Down time Specialized maintenance expertise Time to repair Cost to repair Copyright 2010 Rockwell Automation, Inc. All rights reserved Copyright 2012 Rockwell Automation, Inc. All rights reserved.

8 ECT Product Portfolio TurboPAC SurgePAC PerformancePAC LoadPAC & NetPAC SpeedPAC FuelPAC CentrifugePAC TM AirPAC PACView SimPAC VibrationPAC TM Copyright 2010 Rockwell Automation, Inc. All rights reserved Copyright 2012 Rockwell Automation, Inc. All rights reserved.

9 9 Cryogenic Process and Plant Layout

10 10 Cryogenic Plant Process Flow Diagram

11 11 Cryogenic Plant Process Recovery of C3 and C4 fraction from LPG-rich gas streams Source Upstream Gas Concentration Unit and Propylene Splitter LPG Recovery Conditions Pressure: 20 bar g (medium pressure) Temperature: -78 ºC Critical Turbomachinery Two centrifugal compressors in series to increase gas pressure 1 Electric motor compressor unit (K-2) 1 Turbo-expander compressor unit (K-3) Two-stage Heat Exchanger to reduce temperature Remaining lean gas returned to fuel gas header system

13 13 Upgrade Project Drivers Plant Outages, Lost Production and Equipment Wear and Tear High-value, high margin product (> $75,000 per day) ESD and Process Control System Mitsubishi PLC Obsolete triple voter processor I/O failures & CPU halts Non-redundant MODBUS link to DCS gateway Compressor Control CCC make S3+ surge and performance controllers Difficult to maintain and service black-box hardware Turbo-expander Control In the Honeywell TDC 3000 DCS In MANUAL, difficult to AUTO start/stop, no process control

14 14 New System Wish List High-availability System on One Platform ESD system for safety, environmental and asset integrity level Process control system Turbomachinery control system Redundant MODBUS link to the DCS gateway Standard components, no black-boxes Turbomachinery Control System Surge control algorithms to handle refrigeration process Advanced control algorithms to handle compressors in series Maximize liquid recovery through automated and synchronized control of Expander IGVs and Bypass Valve Automated process control of critical drum pressures

15 15 Competing System Offerings Rockwell Automation Redundant ControlLogix based ESD and Process control system Bolt-on SIL 2 ECT Turbomachinery Control System VersaView Panel PC HMI Siemens Redundant S7-400 based ESD system SI-developed Generic or Blackbox Turbomachinery Control System SIMATIC Panel PC HMI Triconex I/O extension to existing TMR processors with software upgrade Triconex proprietary Turbomachinery Pack Wonderware Panel PC HMI

16 16 Why Rockwell PlantPAx? ESD, Process and Turbomachinery Control System on common platform ECT Turbomachinery Control System Advantages over competition Guarantee to automate Turbo-expander control Guarantee to maximize liquid recovery Ability to control highly interacting series compressors Lowest installed cost over the life cycle of plant operation Within budget 500,000 including installation and commissioning

17 17 PlantPAx System For Cryogenic Unit

18 18 Cryogenic Unit PlantPAx System Specifics Redundant ControlLogix System with RM modules Independent L62 processor sets for ESD and Turbomachinery control Ethernet ring based IO split into three groups Ring #1 IO: surge control + ESD (non SIL) + process control Ring #2 IO: ESD SIL HMI 15 VersaView PC with ECT ActiveX Components Redundant CompactLogix interface between ControlLogix and DCS MODBUS RTU (RS232/485/232) Communicate status, alarm, process variables data Provide operator interface on the DCS Workstation RS Logix 5000 and ECT purpose-built monitoring software

19 19 Cryogenic Unit PlantPAx System Architecture

20 20 Cryogenic Unit PlantPAx System IO Module AI AO DI DO IF8H 16 IF16 32 IR6I 36 OF8H 08 IB OA8D 16 OA OB16I 32 OB32 32 TOTAL

22 22 Process Control & Sequencing Graphic

23 23 ESD Interlock Graphic

24 24 ECT TurboPAC Turbomachinery Control System

25 25 Cryogenic Unit Turbomachinery

26 26 Motor-driven Compressor (K-2) Issues and Requirements Slow antisurge valve requires advanced surge control algorithms Valves are non-linear with large hysteresis and deadband Surges when downstream K-3 compressor trips Results in trip of Cryogenic Unit Automatic start and loading is required Strong de-stabilizing load interactions with downstream K-3 compressor Multiple mechanical, electrical and process constraints Motor current high limit Discharge pressure high limit Suction drum pressure low limit

27 27 Motor-driven Compressor (K-2) ECT s TurboPAC Control Applications SurgePAC 1 modulates antisurge valve Equivalent map coordinates invariant to suction conditions Surge Control with Adapter, Preventer, Stopper algorithms Limit compressor suction pressure Detect excessive surge condition (3 surge cycles in 5 seconds) Estimate surge limit automatically with Estimator algorithm Provide automatic load/unload functionality PerformancePAC 1 controls compressor suction throttle valve Control D2 drum pressure Limit motor current draw Limit compressor discharge pressure Provided automatic load/unload functionality 1 equipped with Multi-Variable Constraint Control(MVCC) algorithms

28 Turboexpander - Compressor (K-3) Issues and Requirements Slow antisurge valve requires advanced surge control algorithms Valves are non-linear with large hysteresis and deadband IGV actuator requiring innovative retrofit Automatic start and loading Strong de-stabilizing load interactions with upstream K-2 compressor Multiple mechanical, electrical and process constraints Speed high limit Discharge pressure high limit Suction drum pressure low limit Maximize liquids recovery Copyright 2012 Rockwell Automation, Inc. All rights reserved. 28

29 29 Turboexpander - Compressor (K-3) ECT s TurboPAC Control Applications SurgePAC 1 modulates ANTISURGE valve Equivalent map coordinates invariant to suction conditions Surge Control with Adapter, Preventer, Stopper algorithms Detect excessive surge condition (3 surge cycles in 5 seconds) Estimate surge limit automatically with Estimator algorithm Provide automatic load/unload functionality ExpanderPAC PerformancePAC 1 modulates expander IGVs Control D-10 drum pressure (unless constrained) Limit expander speed Provide automatic START/STOP functionality Be MASTER to BypassPAC slave BypassPAC 1 modulates expander BYPASS valve Control D-10 drum pressure (if PerformancePAC is unavailable) 1 equipped with Multi-Variable Constraint Control (MVCC) algorithms

30 30 TurboPAC Control System Diagram

31 31 K-3 & K-2 Cascaded Trip Causes Cryogenic Unit trips if K-2 trips Can continue to operate if K-3 trips without tripping K-2 K-3 can be restarted Older blackbox surge control system could not prevent K-2 from surging and tripping when K-3 tripped. If K-3 tripped, K-2 would trip and Cryo Unit would trip K-3 would trip because process disturbances could not be handled K-3 was operated in MANUAL mode and thus could not correct the process ECT s TurboPAC System prevented surging of K-2 surge when K-3 tripped

32 32 TurboPAC Features Interaction Control and Surge Preventer ECT s TurboPAC System prevents surging of K-2 when K-3 trip Why? Reason #1: K-3 can be operated in AUTO mode Mechanical retrofit of IGV actuator Integrated IGV and Bypass Valve control Reason #2: Surge Preventer and Surge Adapter Algorithms Allow managing disturbances to compressors in series Automatically adjust control response to antisurge valves and capacity control elements depending on the size of the disturbance, speed of the disturbance and location of compressor operating point Reason #3: Interaction Control Algorithm Intelligent, directional decoupling of process loops

33 33 ECT s PACView Software High-speed Recorder K-2 compressor surge test Note that SurgePAC allows only one surge cycle during test

34 34 ECT s PACView Software High-speed Recorder Automatic Loading of the process after K-2 compressor start

35 35 ECT s High-speed Recorder Software Automatic start of K-3 Turboexpander-compressor Process control transitions from Bypass Valve (EX1_Out) to IGVs (PC1_Out)

36 36 K-2 Operator Interface ECT s PACView ActiveX Faceplates

37 37 K-3 Operator Interface ECT s PACView ActiveX Faceplates

38 Turbomachinery Monitoring ECT s ActiveX Dynamic Compressor Map Shows compressor available operating envelope Shows current operation against expected performance Monitors compressor performance

38 38 Turbomachinery Monitoring ECT s ActiveX Dynamic Compressor Map Shows compressor available operating envelope Shows current operation against expected performance Monitors compressor performance Shows ECT s equivalent map coordinate system (Rc vs Equivalent Flow) that is invariant to suction conditions Ability to view in engineering units as Rc vs Actual Flow Polytropic Head vs Actual Flow Pd vs Actual Flow

40 40 Benefits Realized Meets required SIL levels, previously unachievable Increased uptime by eliminating trips due to legacy system shortcomings Average cost per unit trip ~ $50K > 10 trips per year ECT TurboPAC Control System Improvements Prevents cascaded compressor trips Reduces machinery wear Eliminates potential for over-speed from MANUAL starts Eliminates de-stabilizing interactions between series compressors Ability to customize control strategy Payback of less than 1 year on equipment

41 41 Conclusions Project completed on schedule and within budget Benefits realized by using PlantPAx ECT s turbomachinery expertise Common components allow better lifecycle management Reduced maintenance costs No specialists required to maintain blackbox systems One platform system for the entire unit No support calls since handover one year ago Integrated PlantPAx systems provides high value to customers

GE Measurement & Control. OptiComp* Compressor Control Suite

GE Measurement & Control. OptiComp* Compressor Control Suite GE Measurement & Control OptiComp* Compressor Control Suite Contents 2 Overview 4 Anti-Surge 6 Performance Control 10 Integrated Controls 12 OptiComp BN 14 Features & Benefits Overview OPTICOMP* Compressor