Kilns. Reactions involving free-flowing solid, paste, and slurry materials can be carried out in kilns. In a rotary kiln, a cylindrical shell is mounted with its axis making a small angle to horizontal and rotated slowly. The material to be reacted is fed to the elevated end of the kiln and tumbles down the kiln as a result of the rotation. The behavior of the reactor usually approximates plug flow. High-temperature reactions demand refractory lined steel shells and are usually heated by direct firing. An example of a reaction carried out in such a device is the production of hydrogen fluoride  [c.60]

Rotary kilns. Rotary kilns involve a cylindrical refractory-lined shell mounted at small angle to horizontal and rotated at low speed. Solid material, sludges, and slurries are fed at the higher end and flow under gravity along the kiln. Liquids also can be incinerated. Rotary kilns are ideal for treating solid waste but have the disadvantage of high capital and maintenance costs.  [c.300]

In this figure the next definitions are used A - projection operator, B - pseudo-inverse operator for the image parameters a,( ), C - empirical posterior restoration of the FDD function w(a, ), E - optimal estimator. The projection operator A is non-observable due to the Kalman criteria [10] which is the main singularity for this problem. This leads to use the two step estimation procedure. First, the pseudo-inverse operator B has to be found among the regularization techniques in the class of linear filters. In the second step the optimal estimation d (n) for the pseudo-inverse image parameters d,(n) has to be done in the presence of transformed noise j(n).  [c.122]

Computer Model of Thermal Processes in a Cement Kiln for Application in IR Defectoscopy.  [c.418]

For IR defectoscopy of cement kilns one can use the data about temperature distribution over an operating cement kiln surface, obtained with scanning units of thermal monitoring [1],  [c.418]

Local deviations of experimental data from calculated ones can be used to identify defects of a kiln body.  [c.418]

The given computer model of thermal processes in a cement kiln allows to calculate temperature pattern both at a surface and inside a kiln body.  [c.418]

The model allows to perform thermal calculation of a multi-layer annular structure of a kiln body with a granular mixture-clinker, roasted inside it (Fig 1).  [c.418]

All the processes, proceeding in a kiln, are divided into a following (sequence)  [c.419]

For a cell, located close to an outer surface of a kiln the equation of heat balance can be written in the form  [c.420]

For a cell, located close to an internal kiln surface without clinker and for a cell with clinker and contacting with a kiln gas the same equation can be written in tbe form  [c.420]

To speed up the process of attainment of the temperature steady value one can use special operations calculation without a kiln rotation, using large time intervals and calculation in two-dimensional R-tp geometry without regard for heat and mass transfer along an axis The program for realization of discussed simulation algorithms enables to calculate temperature in cells, a total number of which can not exceed 130 thousands A circular kiln structure can contain up to three layers.  [c.421]

The internal kiln surface can contain up to six empty defect zones or zones with thermal physical characteristics different from those of material layers. The initial data are taken from a text file, prepared by any editor in the format MS-DOS. The obtained values of temperatures are written into an output file in the format MS-DOS for subsequent processing with visualization programs.  [c.421]

Fig.3 shows comparison of calculated temperature distribution along the coordinate Z of a kiln cylindrical body with an experimental one.  [c.421]

Fig.3. Calculated (1) and experimental (2) temperature distributions along the coordinate Z of a kiln body Fig.3. Calculated (1) and experimental (2) temperature distributions along the coordinate Z of a kiln body
As it is shown in Fig.3 coincidence of curves is rather good. A calculated curve shows a clearly defined defect in on internal coating of a kiln.  [c.421]

Inequality Re > H corresponds to the other case, when only a part of a penetrant is extracted by a developer and can form crack s indication. Such a situation can take place when one use kaolin powder as the developer. We measured experimentally the values Rj for some kaolin powders. For the developer s layer of kaolin powder, applied on tested surface. Re = 8 - 20 pm depending on powder s quality.  [c.614]

One more obvious example illustrates strong influence of particle s sedimentation upon the sensitivity threshold. Assume that we have to ensure the detection of the cracks with the depth 10 > 2 mm in the case when the same product family indicated above is applied and h = 20 pm. The calculation using formula (1) shows that in the absence of sedimentation only the cracks with the width H > 2 pm could be detected. But when the effect of sedimentation results in the reduction of the value of developer layer thickness from h = 20 pm to h = 8 pm, then the cracks of substantially smaller width H > 0,17 pm can be revealed at the same length lo = 2 mm. Therefore we can state that due to the sedimentation of developer s particles the sensitivity threshold has changed being 12 times smaller. Similar results were obtained using formula (2) for larger particles of the developers such as kaolin powder.  [c.615]

Klein and co-workers have documented the remarkable lubricating attributes of polymer brushes tethered to surfaces by one end only [56], Studying zwitterionic polystyrene-X attached to mica by the zwitterion end group in a surface forces apparatus, they found /i < 0.001 for loads of 100 and speeds of 15-450 nm/sec. They attributed the low friction to strong repulsions existing between such polymer layers. At higher compression, stick-slip motion was observed. In a related study, they compared the friction between polymer brushes in toluene (ji < 0.005) to that of mica in pure toluene /t = 0.7 [57].  [c.447]

J. Klein and E. Kumacheva, Science, 269, 816 (1995).  [c.461]

R. Yerushalmi-Rozen, J. Klein, and L. J. Fetters, Science, 263, 793 (1994).  [c.492]

R. Yerushalmi-Rozen and J. Klein, Langmuir, 11, 2806 (1995).  [c.492]

J. Klein, E. Kumacheva, D. Mahalu, D. Perahia, and L. J. Fetters, Nature, 370, 634(1994).  [c.461]

J. Klein, E. Kumacheva, D. Perahia, D. Mahalu, and S. Warburg, Faraday Disc., 98, 173 (1994).  [c.461]

Very finely divided minerals may be difficult to purify by flotation since the particles may a ere to larger, undesired minerals—or vice versa, the fines may be an impurity to be removed. The latter is the case with Ii02 (anatase) impurity in kaolin clay [87]. In carrier flotation, a coarser, separable mineral is added that will selectively pick up the fines [88,89]. The added mineral may be in the form of a floe (ferric hydroxide), and the process is called adsorbing colloid flotation [90]. The fines may be aggregated to reduce their loss, as in the addition of oil to agglomerate coal fines [91].  [c.477]

E. A. G. Aniansson, S. N. Wall, M. Almgren, H. Hoffmann, I. Kielmann, W. Ulbricht, B. Zana, J. Lang, and C. Tondre, J. Phys. Chem., 80, 905 (1976).  [c.497]

Kellman M E 1995 Dynamioal analysis of highly exoited vibrational speotra progress and prospeots Molecular Dynamics and Spectroscopy by Stimulated Emission Pumping ed H-L Dai and R W Field (Singapore World Soientifio)  [c.83]

See pages that mention the term Khelin : [c.207]    [c.90]    [c.103]    [c.230]    [c.326]    [c.367]    [c.126]    [c.333]    [c.418]    [c.418]    [c.419]    [c.419]    [c.419]    [c.420]    [c.420]    [c.255]    [c.661]    [c.53]    [c.81]    [c.83]    [c.83]    [c.83]    [c.83]    [c.83]   
The organic chemistry of drug synthesis Vol.1 (1977) -- [ c.313 , c.335 ]