Emerson’s Chris Womack highlights a liquefied petroleum gas (LPG) project in Mexico in today’s guest post.
In liquid petroleum gas terminals featuring partial automation, several systems control the plant’s filling racks, custody transfer areas, and safety systems. Filling each truck typically takes about an hour and a half, with a filling error of around 66 lbs. (30 kg)—sometimes much larger.
Until recently, none of Mexico’s LPG terminals was fully automated. So when a large Mexican gas-distribution company planned to build a highly efficient, precise, and safe terminal to supply the country’s West-Central region, it was doing something completely new. Additionally, this terminal would connect to a pipeline owned by Mexico’s national oil company, so it needed to meet demanding environmental and safety requirements, and the national oil company had to be able to monitor all of the terminal’s operations, all the time.
In a presentation from last fall’s Emerson Exchange, Fernando Mirafuentes Sánchez and Patrick Truesdale show how Emerson Mexico worked with the project’s engineering, procurement, and construction contractor to help it meet all those goals using Emerson solutions.
Led by Fernando Sánchez, the Emerson Mexico team and the EPC company evaluated project’s planned control, measurement, and safety components, and replaced them with a comprehensive Emerson solution.
Specifically, the two groups installed a DeltaV distributed control system to automate the terminal, rather than the collection of programmable logic controllers identified in the original plan. Instead of a variety of third-party devices, they used Emerson devices for almost all of the plant’s areas, including using high-precision Coriolis meters at its custody transfer points, and one of our Rosemount pressure transmitters at the outlets of each of the three pumps in the filling racks. And where several safety systems would have controlled gas and flame security, Emerson Mexico and the EPC installed DeltaV SIS to provide complete coverage.
As a result, each part of the terminal’s control, measurement, and safety functions integrated easily with the rest.
So when the Emerson Mexico team helped install and commission the terminal’s systems and devices, the project easily met its start-up deadline with an operational capacity of 20,000 barrels (about 3.2 million L) per day. Eight days later, the terminal was operating at full capacity, moving 40,000 barrels of LPG each day.
The integrated solution has been good for efficiency and accuracy too. Compared to a partly automated LPG terminal, this fully automated plant takes about half as long to fill each truck—less than 45 minutes, compared to 1.5 hours—which greatly improves asset utilization. Thanks to the plant’s Coriolis meters, filling error is now a fraction of what you’ll see in a partly automated plant—about 1 kg, compared to 30 kg or more.
Concerning reliability, both DeltaV and DeltaV SIS have kept it above 99 percent. And in the more than two years that it’s been up and running, that Central Mexico LPG terminal hasn’t experienced a single accident.
And those are the advantages of using an integrated solution for a fully automated terminal.