Abstract: Systems and methods for detecting coking in a wash bed of a vacuum pipe still with a sensing cable including an optical fiber sensor array aligned with a heating element disposed in the vessel. An optical signal interrogator is configured to measure a first temperature profile at a plurality of sensor locations to determine a flow distribution. An excitation source is configured to propagate at least one heat pulse through the heating element and the optical signal interrogator is configured to measure a second temperature profile corresponding to the heat pulse at the sensor locations. A control unit is configured to detect coking by determining one or more properties of the media exposed to the sensing cable at each of the plurality of sensor locations based on the second temperature profile corresponding thereto.

Abstract: A stator-type mixing device is used as a mixing device between fixed catalyst beds in a reactor. The mixing device includes a plurality of blades or surfaces arranged around a central hub. The blades are arranged at an angle relative to vertical so that a fluid cannot pass vertically through the mixing device without contacting at least one blade or surface. The blades or surfaces allow the stator-type mixing device to span the full cross-sectional surface area of the reactor, so that concentration of liquids in a localized portion of the reactor cross-sectional area is reduced or minimized. For reactors where at least part of the process fluid is a liquid under reaction conditions, a distributor tray can be included below the stator-type mixing device.

Abstract: Systems and methods for detecting coking in a wash bed of a vacuum pipe still with a sensing cable including an optical fiber sensor array aligned with a heating element disposed in the vessel. An optical signal interrogator is configured to measure a first temperature profile at a plurality of sensor locations to determine a flow distribution. An excitation source is configured to propagate at least one heat pulse through the heating element and the optical signal interrogator is configured to measure a second temperature profile corresponding to the heat pulse at the sensor locations. A control unit is configured to detect coking by determining one or more properties of the media exposed to the sensing cable at each of the plurality of sensor locations based on the second temperature profile corresponding thereto.

Abstract: A stator-type mixing device is used as a mixing device between fixed catalyst beds in a reactor. The mixing device includes a plurality of blades or surfaces arranged around a central hub. The blades are arranged at an angle relative to vertical so that a fluid cannot pass vertically through the mixing device without contacting at least one blade or surface. The blades or surfaces allow the stator-type mixing device to span the full cross-sectional surface area of the reactor, so that concentration of liquids in a localized portion of the reactor cross-sectional area is reduced or minimized. For reactors where at least part of the process fluid is a liquid under reaction conditions, a distributor tray can be included below the stator-type mixing device.