logo

Back

New design features enhance separation performance

The Shell Schoepentoeter is a vane-type inlet device for feeding high momentum gas-liquid mixtures into separators or distillation columns. The Schoepentoeter has two main functions: separating the liquid from the vapor and evenly distributing the vapor in the gas compartment of the vessel.

While Schoepentoeters have been recognized as the primary choice of radial inlet device in many separator vessels, performance in distillation columns has been challenged by proponents of the tangential vapor horn style inlet device, particularly at high column load factors. The improved design of the next generation Schoepentoeter Plus resolves these concerns, optimizing separation efficiency without compromising hydraulic capacity.

How a Schoepentoeter Works
The Schoepentoeter divides the mixed phase feed stream into a series of lateral flowing streams. The vanes dissipate the kinetic energy of the streams for a smooth entrance into the vessel, and also provide centrifugal acceleration to promote separation of the liquid from the vapor.

Sulzer, in partnership with Shell Global Solutions, studied the Schoepentoeter design and modified key features to accommodate improved de-entrainment performance. Lab test results for the Schoepentoeter Plus showed a similarly high vapor distribution quality as with the conventional design, but significantly better vapor / liquid separation, particularly at the high column load factors.

Improvements in the Schoepentoeter Design
In the updated Schoepentoeter Plus design, new catching rims have been installed at the exit of each vane to convey the captured liquid separately down to the bottom section of the tower, avoiding contact with the ascending vapor. This new feature reduces liquid entrainment by over 60% when compared to the conventional design, without any significant increase in pressure drop.

Case Study: Commercial Separator Application
Excessive aqueous-phase liquid carryover was experienced at the inlet separator of an existing gas processing facility, resulting in chloride precipitates fouling downstream compressor blades and costing critical compressor performance. Sulzer replaced the current equipment with a Shell Schoepentoeter Plus design, reducing entrainment from 4.5% to less than 1.5%, essentially tripling the compressor run length.

Conclusions
The new design features of the Schoepentoeter Plus inlet vane device reduce entrainment down to just 30% of the conventional Schoepentoeter, providing the best possible performance of any radial inlet feed device. Schoepentoeter Plus installation requires less welding and down time compared to other high performance feed devices, making it ideal for revamp applications.

DOWNLOAD LITERATURE

View More

  • Safeguard packed column efficiency with proper liquid distribution

    Initial liquid distribution directly affects the efficiency of structured and random packing beds. As such, some form of flow test should be conducted to validate distributor performance prior to column startup. Steady state water flow testing is the most common method of testing distributors. It can ...

  • Separator technology reduces refinery operating costs and downtime

    A US refining company contacted us to discuss a separation problem in the feed to an alkylation process. Caustic entrainment from their selective hydrogenation unit was poisoning the hydrofluoric acid catalyst in the alkylation unit. The continuous phase feed to the alkylation unit consisted of ~180m3/hr ...

  • Tray designs for extreme fouling applications

    Today refiners experience a lot of problems with processing of opportunity or heavy crudes. Such crudes have very high sulfur content and require the addition of amine scavengers before desalting. These amines decompose in the heater and create ammonium chlorides in the presence of water in the top of ...

  • Anti-fouling trays maximize coker main fractionator profitability

    The Coker Main Fractionator is systematically subjected to harsh operating conditions that can lead to deteriorating efficiency and performance due to coking and fouling. Poor reliability results in loss of profitable coking margins for the refinery. The main fractionator vapor feed from the coke drum ...

  • Improve separation in your column by increasing the number of trays

    Refiners often face revamp challenges when trying to improve separation within an existing column. Improving diesel recovery from gas oil, splitting benzene precursors from naphtha reformer charge, or simply minimizing product overlaps after capacity creep can all be difficult when limited by a fi xed ...

  • Gain 5-10% efficiency with this simple 4-pass tray revamp

    The design of 4-pass trays can be complex. It not only requires a close evaluation of the mechanical design but also the process response to that design at various flow rates. The balancing of the fluid flows across the tray can have a substantial effect on the tray performance, namely efficiency. Many ...

  • Proper design of mass transfer internals in the FCC flue gas scrubber can help reduce PM emissions

    The EPA’s New Source Performance Standards (40 C.F.R. §60.100-1-0, subpart Ja) regulates refinery particulate emissions, including the discharge of catalyst fines from the FCCU flue gas scrubber stack. Because refiners have traditionally correlated particulate matter (PM) emissions with FCCU ...

  • Improve fouling resistance in your wastewater benzene stripper

    Benzene stripper columns, built so that refineries can meet the National Emissions Standards for Hazardous Air Pollutants (NESHAP), operate with several unique conditions – low vapor rates, high liquid loads, and a high tendency toward fouling make designing well-balanced, effective internals difficult. The ...

  • Important tray design features that improve column operating reliability

    How often does Maintenance personnel open a column during a shutdown and find tray panels fallen without any obvious damage? How about tray valves stuck in the bottoms pump suction? While the initial reaction may be to blame faulty installation where the hardware was not properly tightened, the answer ...

  • Green design practices: focus on efficiency

    Green design is more than recycling scrap materials or calculating carbon footprints. It minimizes negative environmental impact through skillful design and operating practices to produce efficient, better-functioning processes. Because green practices reduce resource requirements, in many cases, they ...

  • Responsive image Catalyst portfolio
  • Responsive image FCC catalysts & additives
  • Responsive image ITW technologies online cleaning
  • Responsive image OpX® Digital
  • Responsive image FluegasExact 2700 effective combustion analysis
  • Responsive image Optimize everything plant-wide
  • Responsive image Use your catalyst buying power
  • Responsive image Process catalysts
  • Responsive image The sulphur processing expert
  • Responsive image Process flares