Special Drying Technologies

Kudra, T. and Mujumdar, A.S., Special drying technologies and novel dryers. In Handbook of Industrial Drying, ed. Mujumdar, A.S., Marcel Dekker Inc., New York, 1995, pp. 1087-1149. 

Specifically, the improved solidification (cementation) technology involves the use of (a) a special dry powder admixture for the generation of a nonsoluble crystalline formation deep within the pores and capillary tracts of the concrete—a crystalline structure that permanently seals the concrete against the penetration or movement of water and other hazardous liquids from any direction (b) special nonmetal reinforced bars for enhancing the concrete block s tensile and compressive strengths and (c) a unique chemical crystallization treatment for the waterproofing and protection of the concrete block s surface. 

Many technological processes require dry filler. In some cases the moisture level of the filler must be as low as 0.03%. Special drying equipment overcomes the long drying times and ineffectiveness of more conventional drying ovens. 

Each type of dryer has specific characteristics, which make it suitable or unsuitable for specific applications. Details can be found in Mujumdar (1995). Certain types are inherently expensive (e.g., freeze dryers) while others are inherently more efficient (e.g., indirect or conduction dryers). Thus, it is necessary to be aware of the wide variety of dryers available in the market and their special advantages and limitations. Furthermore, note that the aforementioned classification does not include most of the novel drying technologies, which are applicable for very specific applications. The reader is referred to Kudra and Mujumdar (1995) for details on novel drying technologies. 

In particular in drying technology, numerous experiments found that the use of a special hydraulic diameter is appropriate (Krischer and Kast 1978 Kast et al. 1974) ... 

Technological procedures in the manufacturing of electrodes and other components and the assembly of batteries are carried out in special dry rooms or in sealed glove boxes in the atmosphere of pure argon. Assembly of batteries involves complex state-of-the-art welding technologies, complex designs of sealed tabs, and so on. 

Jezowska A. Kinetics of drying in a cyclically shifted spouted bed. Drying Technology—special issue on spouted beds. Kudra T, Raghavan GSV, eds. 11(2) 319-337, 1993. 

Kudra T. Drying Technology—special issue on dielectric drying. 8(5) 907-1205, 1990. 

Genskow, L.R., Guest Ed., Scale-up of Dryers, special issue of Drying Technology, 72(1-2), 1994. 

Drying Technology—An International Journal, Special Issue on Dielectric Drying, 8(5) (1991). 

The focus of this chapter is on special drying techniques and selected novel dryers. In general, these technologies have specific applications and may offer advantages over conventional drying technologies under certain conditions. To a major extent, this chapter updates a number of other chapters in this hand-... 

Technology has developed for time to stabilize soil at a considerable depth (20). The U.S. method is called time slurry pressure injection, with time slurry being injected in situ to 3—6.6 m depth through lances on a grid-pattern but there is no mixing of time and soil. Both Japan and Sweden have developed techniques using specially constmcted machines to inject dry quicklime and then mixing the time, soil, and water to depths of 11 m or more under critical hydraulic conditions. 

Metallizing Unit cost moderate to high Labor cost moderate to high Investment high Limited Somewhat restricted Critical Good durability Requires special technological know-how Wet and dry process, no tool contact with product. Produces bright metallics. 

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