Transactions of the American Institute of Chemical Engineers Volume 2 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1910 Excerpt: ...working on the counter current-principle), a very slight added heat at the central zone is made to maintain the temperature by creating the differential between the two currents necessary to keep up the transmission from the outgoing to the incoming fluid. A very.slight amount of heat is capable of raising the temperature to a very high degree. Has the same thing been tested in producer work? If more steam than 10 per cent were added the temperature would apparently be reduced. But if both the steam and the incoming air were preheated to 1000 it would be raised again. Would it not be possible then to maintain the zone of maximum temperature (the exit gas preheating the incoming gas) until 15 or 16 per cent of steam could be used? W. D. Enn1s: It is a little difficult to say what per cent of steam might be used; certainly not 15 or 16 per cent, because then we get temperature elevations of only a few hundred degrees. W. M. Grosvenor: I do not think you would be getting any lower temperature, because you would return to the incoming gases all the heat (less a narrow margin for radiation) which was originally generated. W. D. Enn1s: The margin is-considerable. It is a common difficulty in recuperation apparatus to get the desired equalization of temperature. It is very seldom that the gas can be cooled much below 6o00 F., on account of the slow transmission experienced with a low temperature differential. W. M. Grosvenor: In "transferrers" used for contact work the differential does not have to be very great. J. W. R1chards: I wish to congratulate the Institute, if I may, on the first paper read before it being a paper which deals with the quantitative side of industrial operations. I think that is a field where the pure scientists and the industrial...