Raw Materials with Quality
The prevailing pressure in the earth’s interior presses the extracted oil to the surface. Depending on the deposit, the oil is contaminated to a greater or lesser degree with water and sand. Gases also emerge from the underground repository. Separation of the oil from the unintentional components is carried out in the separators. Measurement of the level and detection of the interfaces in the separator are indispensable for effective separation of all components.
Level Measurement with the VEGAPULS 66
To optimally utilize plant capacity, a reliable and accurate level measurement in the separators is necessary. A main requirement is that the measuring system be independent of the composition of the oil-water mixture. Since the conveying pressure and the product temperature depend on the oil deposit, the measurement must also stay unaffected by the process pressure and temperature.
The non-contact VEGAPULS 66 radar level sensor fulfills these high demands. Its ceramic antenna system with graphite seal ensures reliable measuring results in temperatures up to 752°F (400°C) and pressures up to 2320 psig (160 bar). Because it is mounted on a bypass tube, the measurement set-up offers the advantage of easy positioning on vessels which are otherwise covered with many inlets and outlets and have little available space. Moreover, the sensor is not influenced by strong product movement in the separator.
The Separation of Oil from Water
Clean separation of the oil from the water substantially determines the quality of the extracted raw material. Sand residues are just as unwanted as gas residues. Due to their different densities, the various components separate mechanically from each other in the separator.
Radiation-Based Interface Detection with the LSG
The determination of the interface between oil and water is carried out with the radiation-based sensor LSG. The non-contact sensor is influenced neither by process pressure nor process temperature. The unequal damping of the radioactive radiation in the different liquids enables a reliable detection of the interface. Placement of the radioactive sources directly in the container allows operation with low doses of radiation and achieves high measurement reliability. To extend the measuring range while at the same time using only small doses of radiation, two radiation-based measuring systems are implemented for one separator.
Pressure Monitoring with the VEGABAR 53
For the protection of the entire plant, the process pressure in the separator is monitored with the VEGABAR 53 pressure transmitter. Its measuring cell with strain gauge is particularly suitable for very high process pressures up to 14503 psig (1000 bar).
