Electric furnace, tube, construction

Fig. 13. (a) Convection currents around electrically heated furnace tube (b) furnace construction to minimise convection (78). 

To examine the pyrolysis reaction of the scrap tires, pulverized scrap tires were heated in a quartz tube by an electric furnace (h). Then the continuous pyrolysis test plants in Table I were constructed to get the engineering data required for the design of an actual plant,... 

An apparatus as shown in Fig. 8 is constructed. A and B are two gas-washing bottles containing concentrated sulfuric acid and 180 g. of dry bromine, respectively. The pyrex combustion tube C surrounded by an electric furnace leads to a 500-ml. distilling flask E, which is provided with a mercury well for taking temperature readings during subsequent purification of the product. 

The complete assembly for carrying out the catalytic decomposition of acids into ketones is shown in Fig. Ill, 72, 1. The main part of the apparatus consists of a device for dropping the acid at constant rate into a combustion tube containing the catalyst (manganous oxide deposited upon pumice) and heated electrically to about 350° the reaction products are condensed by a double surface condenser and coUected in a flask (which may be cooled in ice, if necessary) a glass bubbler at the end of the apparatus indicates the rate of decomposition (evolution of carbon dioxide). The furnace may be a commercial cylindrical furnace, about 70 cm. in length, but it is excellent practice, and certainly very much cheaper, to construct it from simple materials. 

Of the foregoing alloys nichrome possesses many interesting features. It is now well known for its electrical resistance, and is useful in the construction of electric heating appliances, such as air ovens, muffle and tube furnaces, for use in the chemical laboratory. 

The pyrolysis reactors were similar to those used earlier (1,2) they were 1.1 to 1.26-cm i.d. tubes that were heated in an electrical resistance furnace over a length of about 48 cm. The materials of construction in the four reactors used in this investigation were as follows Incoloy 800, stainless steel 304, Vycor glass, and alonized Incoloy 800. The latter reactor was prepared by Alon Processing, Inc. of Tarentum, Pennsylvania. 

The tubular reactor is made of stainless steel,type 316. It is constructed in the form of a coil about 4 cm, in diameter. In the Hereaus tube furnace, the silica tube is heated electrically to supply heat. The inside diameter of this tube is 6.5 cm and the heated length is 55 cm. The temperature profiles are measured by... 

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