Prospectus

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DSP-12 Small Random Packing Test Expected Benefit toMembers: Small random packing is often used for the separation of fine chemical systems. They have large specific area and consequently, have a low HETP. Present Situation and Proposed Research: Carbon steel 5/8” Pall rings were tested with the C6/C7 system at 5 and 24 psia in 1982. The results are documented in Progress Report for July-August 1982 and September-October 1982. These tests found that the measured HETP strongly depends on the liquid distributors used. Multiple cross samplers that was shown to increase HETP in recent studies were used. The combination of poor distributor quality and use of cross samplers might have resulted in higher HETP than expected. In 1986, stainless steel 5/8” Pall rings was test with the C6/C7 system at atmospheric pressure using the FRI adjustable liquid distributor (Progress Report for January-February 1986). Eight cross samplers were employed. The test results show that the HETP of 5/8” Pall ring was higher than that of 1” Pall ring (Figure 14 in the Progress Report). Again, these results are unexpected. Proposed Internals and Test System: Traditional Research Idea

Estimated Unit Time: Three weeks of unit operation time and two weeks of installation are required to measure the HETP, pressure drop and capacity for the C6/C7 system at 5 and 24 psia. Estimated Additional Costs (Beyond Unit Time): Unknown.

Additional tests with 5/8” rings using modern liquid distributors without in bed samplers are necessary to validate the old data and to confirm and extend the TR152 model. For data consistency, 5/8” stainless steel Pall rings may be used. Other packing such as Super Ring ® , Nutter ring, and IMTP ® can also be considered for practical purposes. Two modern liquid distributors will be used for the test.

Background and Discussion: Topical Report No. 152 concluded that all HETP data for 5/8” Pall rings in the FRI database are elevated by using cross samples or low-quality liquid distributors. All these data were not used in the TR152 HETP model. TR152 HETP model shows that HETP is inversely proportional to the packing area raised to a power of 0.8. All these findings need to be verified by experimental data.

PROSPECTUS

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