As a consequence of the distillation process, raw crude oil is separated into various products, also known as fractions. These fractions are then subjected to solvent extraction, which further removes impurities from finished products by dissolving them in solvent.
The heavy fraction remaining following the distillation of crudes is called petroleum resids. A variety of solvent extraction processes yield deasphalted oil (DAO) from these resids. These oils serve as downstream feedstocks for catalytic crackers and hydrocrackers. Depending upon the system configuration, level monitoring of the separator, preflash, stripper and hot oil phases may include surge and flash drums, separators and strippers.
Magnetrol® has produced an applications brochure for the petroleum refining industry detailing level measurement challenges and solutions for each step of the refining process. This blog post is part of an occasional series describing each application in detail.
Level Measurement Challenges and Considerations
Level control is critical because interface level control of the separator feeds the flash drum, whose level feeds the stripper, and so on down through the rest of the extraction process. Without proper level measurement, the entire system could experience problems and errors. Application extremes include high temperatures, high pressures, and the presence of steam. Level instruments selected for this application must be able to withstand these challenging process conditions.
Level Measurement Solutions
MAGNETROL has produced level solutions for solvent extraction that can be relied on throughout the entire process, in every extreme:
- For point level:
Series 3 float-actuated external cage level switch
- For continuous level:
Eclipse® Model 706 guided wave radar transmitter or E3 Modulevel® displacer-actuated transmitter
- For visual indication:
Atlas™ and Aurora® magnetic level indicators can be supplied with switches or transmitters
For more information on level measurement solutions for solvent extraction and other petroleum refining applications, download the petroleum refining brochure. And for more information on instrumentation for interface level measurement, download the interface brochure.