Production of calcium carbide

US4391786A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Hans-Joachim Kersting · Frechen, DE
• Erhard Wolfrum · Hillesheim, DE
• Willi Portz · Lechenich, DE
• Georg Strauss · Lechenich, DE

Key dates

• Filing date: Sep 14, 1981
• Grant date: Jul 5, 1983
• Expiry date: Sep 14, 2001

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/129
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The invention relates to a process for making calcium carbide by reacting an excess of coke with quicklime in the presence of oxygen in an oxygen-thermal furnace. To this end, the invention provides for precrushed coal to be used as starting material for coke and precrushed lime hydrate (Ca(OH).sub.2) or precrushed limestone (CaCO.sub.3) to be used as a starting material for quicklime. The precrushed materials are mixed and the resulting mixture is introduced into a drying zone and freed therein at 80.degree. to 120.degree. C. from adhering water. Next, the warm mixture coming from the drying zone, and air, are introduced into a calcining apparatus in which the coal constituent is coked and the lime constituent is simultaneously dehydrated or decarbonized, at temperatures of 900.degree. to 1400.degree. C. The thermally-pretreated mixture of starting materials with an inherent temperature of 900.degree. to 1000.degree. C. is then directly introduced into the oxygen-thermal furnace and reacted with oxygen to calcium carbide.