The Jamnagar refinery is the largest grassroot refinery in the world with six PCC (Plant Control Centre), one each for Refinery, Aromatics, CPP, PP, MTF and for port operation. There are total 30 PIBs (Plant Interface Buildings) located across the complex in the safe area near each plant. These PIBs house all the marshalling racks and system cabinets containing I/O modules, control processors, communication interfaces etc. for various control systems. All the signal cables from the field are terminated here. All these PIBs are connected to PCC through redundant fibre optic cables. Operator consoles and engineering workstations are located in PCC for plant control and monitoring. The PIB is manned for initial operation, start-up and shutdown, etc, and a local console is provided for monitoring, calibration, troubleshooting, start-up, etc.
Following control systems are installed at our Jamnagar Refinery & Petrochemical's complex:
- Distributed control System (Foxboro) - 38 nodes
- Emergency Shutdown System (Triconex) - 26 no.
- Fire & Gas System (Wormald) - 35 no.
- Machine Condition Monitoring System (Bentley Nevada) - 23 no.
- Automatic Tank Gauging System (SAAB) - 259 no.
- Burner Management System (AB PLC) - 48 no.
- Fiscal Metering System (Smith) - 33 no.
- Analyser System (ABB/Foxboro) - 375 no.
- Programmable Logic Controller (Allen Bradley) - 200 no.
- Compressor Control System (CCC/Borsig) - 14 no.
- MOV System (Rotork) - 28 no.
- CCTV System (Optilan) - 5 no.
- GTG Control System (GE Mark V) - 4 no.
- STG Control System (GHH Borsig) - 4 no.
- Terminal Automation System (Foxboro)
What are its objectives and key features?
The prime objectives while designing these control systems were independent start-up/shutdown of each unit/plant, high plant availability. Simple and efficient plant operation ensuring operating personnel and plant safety as also system security from unauthorised changes was another issue in consideration. We also wanted the systems to be user-friendly with fast and accurate analysis, while also achieving systematic and planned scheduling and management of product and resources with a 'look ahead' approach for future needs.
Today, the system has features like dual redundant processors, power supplies, communications and a complex wide information network for DCS, F&G and MCM systems with plant wise networks for other control systems employed using 600 kms of fibre optic cables. Except F&G all other systems are integrated with DCS through redundant serial link for centralised operation and monitoring from control room. The F&G system is kept independent from safety point of view. It has self-tuning of control loops and advanced process control applications for
optimisation.
Does the unit employ intelligent field devices? If yes, what are its advantages?
Majorities of our transmitters are smart with digital communication based on Foxcom or HART. The inputs to DCS are mainly Foxcom and inputs to ESD are HART. Smart instruments with digital communication offer certain advantages such as remote configuration and calibration with easy troubleshooting and diagnostic information, leading to a considerable reduction of maintenance manpower.
Tell us about the mode of networking?
We have a DCS architecture divided into four layers:
- Field Bus - This is lowest level network based on IEEE 1118 with 268.5 Kbps speed. Connects all the I/O modules to CPU and is contained within the PIB using twisted pair cable.
- Nodebus - This control network is based on IEEE 802.3 with 10 Mbps speed and CSMA/CD as media access. CPU, communication gateways, serial interfaces, operator/engineering workstation, etc are connected as a station on the Nodebus. We have a Nodebus for each plant and get extended from PIB to PCC using Fibre optic Nodebus extenders (FONBE).
- LAN - This is IEEE 802.4 token-passing network for connectivity between nodes & inter-plant data transfer. Each Nodebus is connected to LAN as a node. We have 5 LANs, one per complex (Refinery, Tankfarm, CPP, Aromatics and PP). Among these, the Refinery LAN is the world's largest of its kind with 347 stations and Tankfarm LAN is world's second largest with 257 stations and longest ever with 19.2 km of length.
- Plant Information Network (PIN) - This is IEEE 802.3 TCP/IP based information layer, which provides connectivity between complexes for graphics transfer, real time data for material balance etc. History server (Foxhistory) is connected to this network for historian & real time process data.
Can you tell us something about the real-time information systems installed in your plant?
Our real time process operation is managed by InfoPlus.21 (IP.21) information gateway that creates an intelligent real time enterprise having real time business, logistics, manufacturing and services. It collects plant data from refinery, aromatics,
Tankfarm, CPP, PP and port operations. It also provides online real time data at any location geographically distributed across sites or offices. Interestingly, this is the first complete integration in Asia and very few plants in the world have this type of integration.
Can you throw light on the global trends in instrumentation, control and automation?
Until a few years ago, the instrumentation industry was quite independent from the impact of changes in microprocessor technology. But recently, the IT impact has triggered off a paradigm shift in the field of control and instrumentation. There is a definite shift from analogue to digital communication and from proprietary to open system architecture in case of control systems. The latest advancements in embedded technology have enabled
remote monitoring and control through Internet and intranet.
How do you visualize the future of the instruments, control and automation, with special reference to the Indian industry?
We are moving towards knowledge-based economy. With the developments in IT, open networks, Internet, etc automation systems will have high level of interface with IT systems for global competitiveness, supply-chain management, producer-consumer interface, quality and market demands. Perhaps the greatest advantage of using open technology is that users are free to choose the best product (hardware or software) to solve a given problem without regard to supplier. Greater familiarities with products chosen significantly reduce the production, integration, training and maintenance costs and thereby increase performance.
Caption!: The world’s largest refinery stands proudly against Jamnagar skies
The state-of-the-art Refinery control room