Recovery Boiler Combustion control system(ccs) & Emergency shutdown(esd).

Transcription

1 Insert Photo Here Recovery Boiler Combustion control system(ccs) & Emergency shutdown(esd). Mario López Jorge Quesada Rockwell Automation Process Solutions User Group (PSUG) November 14-15, 2011 Chicago, IL McCormick Place West

2 Company Profile Carvajal Pulp and Paper is part of Carvajal Group, a privately owned company established in 1904 and headquartered in Cali Colombia, with over 20,000 employees and annual revenues of over US$ 1.5 billion from seven sectors and operations in 16 countries: Technology and Services Information Pulp and Paper Communication Solutions Packaging Education Espacios

3 Company Profile Carvajal Pulpa y Papel is a pioneer in manufacturing paper from 100% sugarcane fiber

4 The Paper Mill Título de la presentación

5 Recovery Boiler What is the purpose of the Black Liquor Recovery Boiler (BLRB)? Economic Reclaims chemicals used during the fiber digestion Environmental Closures the process avoiding waste water impact Concentrators Bagasse Weak BL Strong BL Flue gases Digester Steam Recovery Unit Pulp White liquor Caustisizing Smelt Green liquor Water

6 Recovery Boiler Recovery Boiler = Chemical Reactor Source: Black liquor recovery: How does it work? Magnus Marklund

7 Recovery Boiler Operation Risks Problems of operation and safety exceed those of conventional power boilers All details of the smelt-water reaction are not thoroughly understood and fundamental information is still lacking Most BLRB explosions have been due to the reactions with molten smelt and water in some form or low solids liquor Uncontrolled ignition of an accumulation of unburned fuel from the auxiliary burners/ gases from pyrolyzed black liquor Dissolving tank explosions due to excessive and uncontrolled smelt runoff or excessive high density in the dissolving tank.

8 Recovery Boiler Process Requirements High Availability Safe Operation Reliability Main Systems Feedwater and condensate Air and flue gas Black liquor firing Auxiliary fuel burning (start up and load increase) Soot blowing

9 Recovery Boiler Process Control CCS: Combustion Control System Regulatory control: drum level, furnace pressure, etc Discrete control: water pumps, ID fan, FD fan, etc. BMS: Burning Management System Safe operation of auxiliary fuel ESP: Emergency Shutdown Procedure System Reliable shutdown if water is known or suspected to be entering the furnace (i.e. leaking pipe)

10 Recovery Boiler The need for upgrade BLRB data Manufacturer: Ahlström-Varkaus Design yr: 1972 Installation yr: 1973 Issues: Some failures were hard to fix Lack of spare parts for obsolete components Reliability could be compromised.

11 Control Room Copyright 2011 Rockwell Automation, Inc. All rights reserved.

12 Process Audit An audit to evaluate the BLRB risk was conducted Identified critical aspects System integrity Safe operation requirements.

13 Process Audit Set a road map with priority levels: A) To do now: ESP upgrade, flame scanners and refractometers B) To plan for soon: BMS upgrade C) To plan for the future: CCS upgrade.

14 Recovery Boiler Challenges System requirements NFPA Regulations NFPA 85 Boiler and Combustion Systems Hazard Code NFPA 86 Furnace and Ovens Industry Practices BLRBAC Black Liquor Recovery Boiler Advisory Committee.

15 Safety Instrumented System Requirements BLRBAC Guidelines for Safety Instrumented Systems (1) : There are no specific technology requirements: electronic relays and timers, solid state logic types, programmable electronic systems, hard wired logic or combinations of them. Applications include: ESP, Rapid Drain Safe Firing of Black Liquor Safe Firing of Auxiliary Fuel (1) Instrumentation Checklist and Classification Guide for Instruments and Control Systems Used in the Operation of Black Liquor Recovery Boilers.

16 Safety Instrumented System Requirements General Recommendations for ESP and Burner Management: Requires several features related to hardware robustness: Fail safe state on failure Non-volatile memory Maximum time to read field inputs/initiate action, etc. Requires several features related to program integrity and change control Password On-line modifications not permitted No share of any single fault, etc.

17 Safety Instrumented System Requirements Requirements Applied to ESP: Redundant methods or processor to ensure ESP initiation Bumpless transfer between processors Alternate means of operation or alternate entry points if a digital control system is used (network redundancy accepted) Rutinary Backup and auto transfer for processor redundacy testing SIS logic state retention should have power from an independent source Requirements Applied to Burner Management: Conformance to BLRBAC, FM, NFPA, UL, etc. Master fuel trip relay / hardwired master fuel trip switch accessible to the boiler operator. Trip sequence initiating device indication

18 CCS - Control System Requirements BLRBAC Guidelines for Recovery Boiler Control Systems (1) : Fail safe mode Firm power source Backup system Critical loops backup Communication redundancy Man machine interface System security (1) Instrumentation Checklist and Classification Guide for Instruments and Control Systems Used in the Operation of Black Liquor Recovery Boilers.

19 Technology Selection Application Logic Complexity I/O Requirement I/O Count HMI Requirement Implementation ESP Low Digital Low DI: 20 DO:10 Low Hardwired BMS High Digital High DI: 150 DO:80 Low Digital Controller CCS Medium Analog/Digital High AI:140 / AO:40 DI:190 / DO:100 High Digital Controller

20 Vendor Selection Criteria Key Aspects to be Considered Proven Technology Proven Application Knowledge Life Cycle Cost Technology (TCO) Initial Investment Local Support Spare Parts Management. $ Application Expertise Life Cycle Cost RA proved to provide the best balance of the aspects above.

21 Rockwell Application Upgrade implementation CCS: Combustion Control System PlantPAx ESP: Emergency Shutdown Procedure Syst. Safety relays BMS: Burning Management Syst. (By COEN) PlantPAx.

22 Rockwell Application Combustion Control System Architecture

23 CCS and ESP CCS Redundant Controllers

24 ESP Obsolete ESP System New ESP System

25 Improved Operation

26 System Integration REMOTE ACCESS CORPORATE NETWORK 3 CLIENT BOILER 6 2 SERVER FT VIEW SE CLIENT BOILER 5 FIREWALL FT-HISTORIAN ASSET CENTRE DN B6 2 CLX Boiler 6 Peripheral CN FLEX I/O MCC MV 6 nodes 3 MCC LV 66 nodes MICROLOGIX Precipitator ETHERNET 2 COMPACT LOGIX Blowers Condensated CN FLEX I/O CLX Boiler 5 FLEX I/O CN B5 CLX Turbo 2 PF S7 Siemens Turbo 2 REDUNDANT CLX BMS REDUNDANT CONTROLNET COMPACT LOGIX Turbo 1 2 REMOTE CHASIS 2 SW ETHERNET Stratrix 2 CLIENT Double Head Recovery Boiler REDUNDANT CONTROLNET PANEL VIEW REMOTE CHASIS SERVER REDUNDANT ETHERNET REDUNDANT CLX ELECTRIC CUBICULE BLRB REDUNDANT ETHERNET ESP PANEL ESP

27 Benefits Provided Employees with a Safe Work Place Improved Operation and Maintenance through Process Integration Physical Assets and Business Continuity Preservation Customers Satisfaction and Market Presence Decreased Cost of Risk Decreased Life Cycle Cost.

28 Conclusions Technology is not enough, application expertise is crucial for project success Go digital is not always the best, see if it fits your application Take advantage to reduce Life Cycle Costs: Initial Investment Local Support Spare Parts Management Negotiate the full package.

29 Questions Insert Photo Here Mario López Jorge Quesada Rockwell Automation Process Solutions User Group (PSUG) November 14-15, 2011 Chicago, IL McCormick Place West Copyright 2009 Rockwell Automation, Inc. All rights reserved.