UOP Dense Loading
Research backed by years of refinery experience has established that reducing void fraction and controlling catalyst particle orientation helps prevent reactor flow maldistribution. UOP's proprietary catalyst dense loading system increases catalyst bed density and uniformity by means of the unique way which the catalyst bed is loaded. As a result of this increased density and uniformity, producers operating a fixed bed catalytic process unit gain the ability to increase operating severity, run longer cycles and/or process more fresh charge stock in their process units.
Process improvements resulting from improved density include:
- More uniform reactant distribution,
- Longer cycle length or higher throughput, or both,
- Better selectivity,
- Lower reactor temperatures.
The average catalyst particle orientation will also affect liquid distribution depending on how the catalysts are oriented. Liquid flows over a catalyst particle in a packed bed and tends to collect at the low points of the individual particles. In a bed of extruded catalyst, liquid will tend to be redistributed to the sides of the reactor if the catalyst bed is mounted, or to the center of the reactor if the catalyst bed is dished. While liquid redistribution in a bed of spheres is not as significant as in a bed of extrudates, dense loading has been shown to improve the liquid distribution by orienting the spheres closer to the ideal rhombohedral packing.
After identifying key variables in a detailed statistical analysis, UOP improved the design of the dense loading machine to deliver consistently flat catalyst bed profiles, which translate into improved unit performance. The new dense loading machine has been designed to handle increased catalyst flow while streamlined internal passages minimize catalyst breakage. The new distributor rotor has also been designed to load faster while maintaining better control of catalyst bed profiles. Dimensional control has been improved, resulting in more consistency in loading. Mourik is one of the few contractors that is licensed to use this UOP dense loading machine in the USA.
