(78f) SimulFlow™ Device - Capacity Beyond System Limit
AIChE Spring Meeting and Global Congress on Process Safety
Tuesday, April 24, 2007 - 4:50pm to 5:20pm
The SimulFlow device is a next generation mass transfer device with a capacity beyond the calculated F.R.I. (Fractionation Research, Inc.) system limit. The device has been primarily developed to alleviate distillation column bottlenecks which contain high capacity trays or to double the capacity of a column containing conventional trays. The SimulFlow device is capable of achieving a significant capacity increase while maintaining or improving product purities.
These extraordinary capacities are achieved by simultaneous liquid and vapor flow against gravity within a contacting channel (cocurrent flow) and efficient vapor/liquid phase separators. Each stage is comprised of individual linear modules of varying horizontal length to accommodate a circular column area. Each successive stage is rotated by 90 degrees in order to ensure uniform fluid distribution throughout the column. These features form a unit cell structure, allowing predictable results at various column diameters with high confidence.
Testing in the UOP 8-foot diameter air-water column has indicated that the SimulFlow device hydraulic capacity is ~235% (constant liquid/vapor ratio) that of a conventional valve tray, at a pressure drop which is significantly lower. Further testing in an F.R.I. 4-foot diameter distillation column with iC4/nC4 at 100 psia (6.9 bar) demonstrated a potential capacity which exceeds the calculated F.R.I. system limit at a low, 16-inch (406-mm) stage spacing. The operating flexibility of the device was established at F.R.I. by consistently achieving a stage efficiency of ~70% across an operating range of more than 2 to 1.
At these test conditions, the SimulFlow device at a 16-inch (406-mm) stage spacing is generating the height equivalent to a theoretical plate (HETP) comparable to a tray at a typical 24-inch (640-mm) tray spacing with an efficiency of 105%. Therefore a column containing SimulFlow devices can generate the same number or more theoretical plates in a given height as compared to high capacity/conventional trays.