Talk:Rotary kiln

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"conduction, convection, radiation" were listed "in order of ascending efficiency"

Changed to "in order of descending efficiency"

While radiative heat transfer may be highly efficient on an atomic level (all radiated energy is carried by a photon and is received entirely by another atom), in the case of a rotary kiln and many other industrial processes, conduction transfers the most heat since materials are in contact (especially slurries) and being stirred.

Please let me know if you disagree with this rational. User:M.eisner

I agree that the article was badly phrased. The order of efficiency depends upon the temperature zone: where the temperature of the gas is low, radiation is obviously only a minor contributor to heat exchange. However, in the region of the flame, particularly if it's a hot flame (over 1800 C), most of the heat transfer is by radiation, because of the T⁴ law. The point I was trying to get across is that, in the cooler parts of the kiln where radiant heat transfer is not available, elaborate devices are needed to encourage transfer of heat by other means. It needs to be re-written to make this clearer. . . .LinguisticDemographer 19:04, 21 October 2007 (UTC)