Process for obtaining paraffin or paraffin fractions

US6074548A · kind A · utility

Assignees

• Schumann Sasol GmbH & Co. KG · DE
• Sulzer Chemtech AG · CH

Inventors

• Norbert Matzat · Munich, DE
• Gunther Hildebrand · Meuselwitz, DE
• Ferdinand Richter · Hamburg, DE
• Manfred Stepanski · Buchs, CH
• Florian Lippuner · Gams, CH
• Herbert Engstler · Frastanz, AT
• Bernhard J. Jans · Buchs, CH

Key dates

• Filing date: Jul 16, 1998
• Grant date: Jun 13, 2000
• Expiry date: Jul 16, 2018

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F28F3/027
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A process for fractional crystallization of paraffin from mineral oil based and synthetic crude paraffin, wherein crude paraffin having a high oil content is crystallized in a crystallizer equipped with perforated metal sheets (31) extending in a zig-zag in the spaces between the heat exchanger surfaces (39). The paraffin-containing melt is only solidified to an extent such that the fractions and oils for discharge remain liquid and are run off without total solidification of the melt. The perforated sheets (31) support the layers of crystals (43) and during sweating the paraffin is detached in strips from the heat exchanger surface (39) and is adapted to rest on the sloping perforated sheets (31). The inclination of the perforated sheets (31) guides and moves the paraffin strips (53), so that the paraffin strips remain in contact with the heat exchanger surfaces (39) while being pressed by their own weight along the inclined surface (30) towards the heat exchanger surfaces (39).