Ceramic retorts

Distillation retorts and furnaces are used either to reclaim zinc from alloys or to refine crude zinc. Bottle retort furnaces consist of a pear-shaped ceramic retort (a long-necked vessel used for distillation). Bottle retorts are filled with zinc alloys and heated until most of the zinc is vaporized, sometimes for as long as 24 h. Distillation involves vaporization of zinc at temperatures from 980 to 1250°C (1800 to 2280°F), and condensation as zinc dust or liquid zinc. Zinc dust is produced by vaporization and rapid cooling, and liquid zinc results when the vaporous product is condensed slowly at moderate temperatures. 

Hojanas Also called Siurin. An iron extraction process. Magnetite, mixed with carbon-coke breeze and limestone, is heated in a ceramic retort by passage through a tunnel kiln at 1,200°C. Used commercially in Sweden since 1911. See also DR. 

The process was carried out in a ceramic retort (inside a furnace) and bird-beak condenser (outside the furnace). Acid composition was adjusted by adding or evaporating water. 

Beddoes to Black, 21 April 1789. This burning glass is the only piece of Beddoes s laboratory apparatus that has been unequivocally identified as his in the Museum of the History of Science in Oxford University, which once housed the university s chemical laboratory. The Museum also houses ceramic retorts made by Wedgwood, and these may have been acquired and used by Beddoes, who ordered apparatus from Wedgwood. See note 53 below. 

The Museum of the History of Science, Oxford University, has some ceramic retorts (inventory nos. 37798, 42340, 49504) and combustion tubes (47565, 44886, 52033) made by Wedgwood, dated to the early... 

Gefass-kunde, /. ceramic art. -ofen, m. (furnace containing receptacles), retort furnace, crucible furnace, pot furnace, etc. gefasst, p.p. p.a. see fassen. 

The process considered is the Colony hydrotreated shale oil plant using the TOSCO II pyrolysis retort (4). In this process raw shale, crushed to 1/2" or smaller, is contacted with hot ceramic balls in a rotating drum. Downstream of the retort the balls and spent shale are separated by screening. The balls are then transported by an elevator to a vessel in which they are reheated by direct contact with hot combustion gases. The heated balls are then recycled to the rotating retort. 

In order to obtain light and porous barium oxide barium carbonate is mixed with petroleum coke having a low ash content or with finely ground pitch or with lamp black this mixture is calcinated at a temperature of 1200—1300 °C in a battery of retorts heated by generator gas and placed in a brick chamber. The retorts are made of special ceramic material with addition of carborundum. 

In a dense-bed fluidized bed the preheated shale is further heated to and held at the retorting temperature for sufficient time to complete the pyrolysis reactions (Figure 3). The total inventory of shale in the retorting vessel is determined by the required residence time for complete kerogen conversion and the shale throughput. The retort heat requirements are supplied by ceramic balls which circulate in the inner loop. They are reheated in a separate vessel which may operate as a moving bed, raining pellet bed, or entrained flow heater. 

For the corrosion of ceramics by ordinary liquid media, the testing is usually done by immersion tests the sample is placed in a heated retort or autoclave inside a stirred excess of corrosive medium. Common test conditions are at the boiling point of the medium (e.g. 10% H2SO4, 30% NaOH) for a week. 

Higher concentration was obtained by coal fi red furnace using retorts in cascade format to produce 97-98% Acid. This was marked in glass carbouys or ceramic jars to consumers. 

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