Flowmeters eliminate cleaning
Shell Chemicals, at Moerdijk, the Netherlands, operates one of Europe’s largest ethylene plants, where Emerson’s Vortex 8800CD dual-vortex flowmeters improved plant steam-measurement reliability. The meters provided two flow measurements on the main steam lines: one for plant process control and a separate measurement for the plant safety instrumented system.
Shell found that vortex metering delivered more reliable steam-flow measurement, increasing plant uptime. Furthermore, plant operators have a better, more accurate steam-flow measurement, allowing production optimization.
Shell’s naphtha-cracker process mixes accurate proportions of light distillate feed-stock (LDF)—such as naphtha or ethane—and steam, heating them to a high temperature in a furnace, cracking the LDF into basic feedstocks like ethylene, and also creating some carbon and coke deposits, that recirculate with process water.
To remove these deposits and assure measurement reliability, a monthly cleaning schedule had been established for each flowmeter.
Engineers conducted a three-month trial with a Rosemount 8800CD on one furnace line. Thereafter all 20 furnaces were scheduled to be equipped with the dual-vortex measurement systems. The first eight furnaces have now operated for over two years, without flowmeter removal for cleaning.
For more information, visit www.GoToEmerson.com .
—Richard Phelps, senior editor, Control Engineering,
richard.phelps@reedbusiness.com
Do you have experience and expertise with the topics mentioned in this content? You should consider contributing to our CFE Media editorial team and getting the recognition you and your company deserve. Click here to start this process.