Length grading

The particle length distribution of a catalyst has a direct impact on the pressure drop characteristics of the reactor into which it is loaded. Catalyst size issues, such as short average length or a high percentage of short particles, can cripple a reactor's performance. In order to recover particles of good length, Porocel has developed a sophisticated screening technology that allows the separation of catalysts particles with a length up to twice the diameter to be efficiently removed without excessive catalyst losses.

Length grading technology results in improved catalyst performance and longer reactor run lengths.

Technology description and benefits

When conventional screening is used to increase the average length of a catalyst, significant losses are likely to occur. Screening can only remove dust, fines, and particles that are smaller than the catalyst diameter.

Once a screen aperture exceeds a catalyst's diameter, yield loss becomes more prominent.

In contrast length grading process ensures highly efficient separation at any length, with an optimal yield.

The material prior to length grading is sampled to measure the fines content as well as the particle length distribution. The particle length distribution is measured by means of an analytical imaging technique ·· measuring the length and diameter of a few hundred particles. Based porocel.com on this weighted particle length distribution a decision can be made how much of the particles need to be removed and what average particle length will result after length grading. Thus, it becomes possible to assess the expected yield and quality of the batch after length grading in combination with the cost of the regeneration.

Length grading can be performed on any batch of catalyst or extrudates: fresh, spent, or regenerated.

Length grading as part of a regeneration job is best performed before regeneration so that short particles are not unnecessarily regenerated.

All the formalities related to packaging, transportation and customs clearance of the catalyst the company OptimLine Technologies shall settle on its own.

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