Prospectus

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DST-32 Investigating Performance of Two-Weight Valve Units on 1-Pass Valve Tray Expected Benefit toMembers: To give the tray designer greater confidence in choosing which combination of light and heavy valves to deploy on crossflow valve trays when turndown requirement is of importance. Present Situation and Proposed Research: The following tests are proposed to investigate the validity of the two-valve-weight heuristic: a) 10.8% VCA 1-pass valve tray, deploy 40% 12 ga. and 60% 16 ga. valve units (like the 2 pass tray). b) 10.8% VCA 1-pass valve tray, deploy 40% 14 ga. and 60% 16 ga. valve units (like the 2 pass tray). c) 10.8% VCA 1-pass valve tray, deploy 40% 14 ga. and 60% 18 ga. valve units (like the 2 pass tray). All tray designs will have 13% DC’s, outlet weir height 2 inched and DC clearance 1.5 inches. This will allow comparison to the Phase 2 two-pass design as well as comparing designs with both one-gauge and two-gauge weight differences. For each valve tray layout, conduct total reflux efficiency runs with C6/C7 at 4.5 and 23.5 psia (0.31 and 1.62 bara). C4’s and perhaps non-hydrocarbon system such as IPA/H20 could be run in a future test. Checking the current valve tray hydraulic/efficiency models using non Traditional Research Idea

hydrocarbon data would be very useful. Proposed Internals and Test System: Unknown. Estimated Unit Time: 9 – 10 weeks including install and tray deck switch outs. Estimated Additional Costs (Beyond Unit Time): Unknown. Background and Discussion:

Consistent with Layton Kitterman’s two-valve-weight heuristic, which states that dual valve weight trays should have at least a two-gauge weight difference, Glitsch employed 16 and 12 ga units in contrast to the common practice of deploying 16 and 14 ga valve units. Glitsch argued that the difference in weight between 16 and 14 ga valve units is insufficient for reliable design, and that FRI results on the old valve tray design (1950’s) with 16 / 14 ga valve units show significant loss of efficiency at low vapor rates.

PROSPECTUS

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