Bayer Aktiengesellschaft

Hans Rinkes

Hans-Heinrich Moretto

Hans-Dieter Block

Rainer Weber

Norbert Lonhoff

Rainer Bellinghausen

Bernhard Spreckelmeyer

Uwe Arndt

Michael Batz

Heinrich Helker

Bruno Degen

Gebhard Wagner

Werner Joseph

Elke Licht

Manfred Schulze

Hans-Georg Nieder-Vahrenholz

Alfred B Orsting

Paul Strehlow

A method for the decomposition of chromium ore in a directly heated revolving tube is described, in which oxygen-containing gases are introduced into the revolving tube by means of below-bed nozzles.

Method for manufacturing alkali chromates from chromium ore

Fine particle silicon containing surface-bound halogen, a process for

A method for manufacturing alkali chromates by the reacting of chromium ore with alkali compounds and oxidation in an atmosphere containing at least 50% oxygen is described, in which the mixture consisting of chromium ore, alkali compound and optionally leaning materials is heated in a first stage in an atmosphere containing not more than 5 vol. % oxygen to a temperature between 1000.degree. and 1 400.degree. C., and in a second stage is oxidized at a lower temperature of 900.degree. to 1 070.degree. C. with supply of an atmosphere containing at least 50% oxygen.

An electric furnace for the continuous melting of frits for inorganic oxidic surface coatings, comprising a substantially rectangular melting chamber, a working chamber separated from the melting chamber by an immersion dam, means for the introduction of raw materials to the melting chamber, and electrodes within the melting chamber for the transmission of electrical energy to the melt, the ratio of the effective electrode surface area to the area of the bottom of the melting chamber being less than about 0.1. Advantageously the supply of energy to the electrodes is regulated by supplying a constant current with a constant output stream, the surface of the melt is covered with about 1 to 10 mm of unmelted frit, the average dwell time of the melt in the furnace is from about 3 to 6 hours, the frit is free from nitrates, the melt is about 5 to 20 cm deep and the frit is introduced thereto from a height at least 50 cm above the level of the melt.

Method and apparatus for melting frits for inorganic oxidic surface

Growing community of inventors

Koln, Germany

Hans Rinkes