Kiln wall

The time constants characterizing heat transfer in convection or radiation dominated rotary kilns are readily developed using less general heat-transfer models than that presented herein. These time constants define simple scaling laws which can be used to estimate the effects of fill fraction, kiln diameter, moisture, and rotation rate on the temperatures of the soHds. Criteria can also be estabHshed for estimating the relative importance of radiation and convection. In the following analysis, the kiln wall temperature, and the kiln gas temperature, T, are considered constant. Separate analyses are conducted for dry and wet conditions. 

Fig. 5. The impact of moisture iu the sohds on the temperature profiles of the sohds at a kiln wall temperature of 330°C, 0.5 rpm, and a fill fraction of 3% ...

Extremely dense structure, large alite Kiln wall (Fundal, 1980)... 

Pryce,M.W., "Calcium Sulphosilicate in Lime-Kiln Wall Coating," Mineralogical Magazine, Vol. 38,1972, pp. 968-971. 

Kilmo. Computer software for calculating heat flow through kiln walls, and heat flow and air flow in the kiln. (Donald Shelley, UK). 

Figures 7.6 and 7.7 are calculated shell losses based on refractory type and thickness. Although the actual mechanism of heat loss through a rotary kiln wall is more involved, the obvious result is that...

Figure 7.8 Cross sectional view of heat conduction through rotary kiln wall.

Modified Penetration Model for Rotary Kiln Wall-to-Bed Heat Transfer... 

The coating in the burning zone protects the refractory lining from wear and improves the thermal insulation of the kiln wall. As a rule, therefore, coating is a desirable feature. However, under adverse conditions it may become too thick or, as already mentioned, form objectionable rings. There are various methods of removing such excess features. 

Temperature morritoring is provided for the absorber surface and the kiln wall by thermocomples placed approx 20 cm from the surface of the kiln. The temperature display with limit value indication can be checked by the operating staff of the eement works in the control room. 

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