The PetroChina Northwest Sales Center Xigu Oil Tank Farm has been in operation for around for 50 years, but some things have changed at the farm since 2010.
The company decided to implement a modern intelligent control system in a retrofit project that year. Since then, instead of engineers going around the facility and taking pressure measurements along the pipelines from time to time, there are intelligent sensors fixed along the pipeline which do the same and send updates every five seconds to the central database.
This is only one of the many functions at the plant that have been automated. This system was installed by Honeywell Process Solutions, a division of Honeywell Automation and Control Solutions, part of the Honeywell company that does business of $37 billion worldwide.
No costly wiring
PetroChina saved on costly wiring for the network as the entire system is wireless, with the instruments supported by batteries that have a life of as much as 3-5 years. Installation and maintenance costs are reduced, and so is commissioning time, said officials at the Xigu tank farm, which this correspondent visited on a trip sponsored by Honeywell.
Industrial wireless systems help manufacturers more easily obtain information from critical areas of their plant in a cost-effective manner, said Mr Soroush Amidi, Senior Marketing Manager at Honeywell Process Solutions.
Sometimes these critical areas are difficult to wire up; at other times they are difficult to access, and automation makes it safer for people working at the plant. Human errors made when taking down measurements and entering them in the central database, are also minimised.
Apart from the application of Honeywell's ‘Experion Process Knowledge System' for stock management, oil product movement, order management CCTV monitoring, access control and performance management, there were other requirements at the tank farm.
Network integration
This was all integrated in a single wireless network which supported pressure data collection for the oil pipeline, monitoring of real time status of root valve, integrated with the control system through native communication protocol.
The challenge was also to add 20 pressure measurement points located in the remote pump building area and avoid damage without a new cable tray and cable conduit.
Provisions had to be made for easy expansion in the future to add more measurement points.
Any delay in getting signal across may mean safety hazard or loss of availability of plant (tripping) production loss, said a Honeywell executive.
Honeywell has used the open wireless standard ISA 100.11a which uses the 2.4 GHz band which is unlicensed and freely available everywhere.
Honeywell's OneWireless solution has at its centre the One Wireless Network. This incorporates field devices as well as Wi-Fi-enabled devices, including laptops, cameras, communication and other devices into a single network.
One can monitor the status of equipment, view process trends, locate assets, locate other colleagues and use video collaboration to troubleshoot equipment from a single handheld device connected to the process control network.
Key challenge
At Petrochina the project took eight months for implementation but the evaluation and preparation for it took two years, said officials.
The existing software was entirely replaced by Honeywell software. But existing hardware was reused to the maximum.
The biggest challenge was that there was no successful reference for the project, and that operations had to carry on right through the installation process.
Apart from the cost savings at PetroChina, truck servicing time for filling a 20-tonne-capacity truck has come down from 50 minutes a truck to 30 minutes. As the system allows self-service to the truck driver, the number of operators at the plant required for this process has reduced from 16 employees a shift to two employees a shift.