Chamber dryer

In larger factories the fruit is steamed on the shelves of chamber dryers or on the belt of belt dryers. 

In commercial practice, ceramic ware is dried in chamber dryers or in continuous tunnel dryers through which the ware is conveyed on cars. Efficient drying requires careful control of air temperature and humidity. The heat is usually transmitted to the ware surface by air convection or radiation from IR sources. Uniform drying is attained by suitable arrangement of the heat sources and by air circulation. 

Drying chambers are generally used for small quantities, and in cases where most of the work is done over night, without supervision. Fuel and steam consumption is therefore rather high. Figure 21 shows a standard chamber dryer with upward direction of the air. Figure 22, the same type with downward movement, which is some times desirable to reduce the speed of the air... 

Figs. 21, 22, 23.—Chamber dryers with upward air current. 

Rubber and electrical insulating material should be treated in standard chamber dryers or vacuum-shelf dryers, with or without the recovery of the so Ivents. Shel dryers are more expensive to install, but the saving in steam quickly pays for the extra expense. Explos ves are handled in vacuum-shelf dryers, especially built for this purpose, with and without recovery of the solvents. The drying housing is equipped with large automatic doors which will open in case of explosion. 

Potatoes are first cooked, and the pulp is spread by rollers over the surface of large steam heated drying drums. Bituminous coal and all kinds of granular material are handled in tubular dryers. Soap is dried when in pieces in chamber dryers, and soap flakes are handled on ribbon dryers at low temperature. Starch, casein and similar products are handled in tunnel dryers and also in rotary vacuum apparatus. Food products, fruits and vegetables are usually dried by hot air in chamber dryers. Vegetables have also been handled under vacuum, which has given an excellent product. 

Chamber dryers equipped with stirrers are commonly nsed for drying of flotation concentrates (Figure 51.4). The dryer operates in a cocurrent mode. Hot combustion gases supplied to the dryer by a duct (5) meet at the outlet the cold and moist coal supplied by another duct (7). The dryer consists of a chamber (1) fitted with baffles (9) and two shafts (2) rotating... 

FIGURE 51.4 Chamber dryer equipped with stirrers. 

FIGURE 62.27 Scheme of the chamber dryer with controlled air parameters (T, and air (gas) blow W. 

The fluid-bed dryer operates under negative pressure in which drying gases are drawn from the heat source through a fluidizing chamber. Dryer and furnace temperature controllers are employed in the control system to readjust the heat input to match the evaporative load changes. 

Chamber dryers are also commonly used as drying cabinets in the laboratory or on a pilot scale. 

Kiln dryers for lumpy, flat and solids pieces are also chamber dryers with huge chambers, from the point of view of process engineering. The product is spread on immovable or moving trays, or turned and moved over the trays using wipers or blades. 

Tiinnel dryers [5.1, 5.2] work with the same principle as the chamber dryer, but allow continuous operation to dry anything from large lumpy solids to pasty products. Trucks with trays on top of each other with evenly distributed wet product pass through a channel or tunnel, in which the drying gas flows over and/or through the wet product. 

Chamber dryer pellet-like, pasty small quantities 0.15-1.5 for product gas overflow 0.1-12 for product gas through-flow 6000-15000 Layer thickness on a kiln 20-100 mm b... 

Chamber Dryer. A type of dryer in which shaped clayware is placed in chambers in which the temperature, humidity, and airflow can be controlled the ware remains stationary during the drying process. The Keller Dryer is of this type, its distinctive feature being the system of handling the bricks to be dried by means of stillages (q.v.) and FINGER-CARS (q.V.). 

Cornish Stone. See china stone. Corridor Dryer. Term sometimes used for a CHAMBER DRYER (q.V.). 

Dryer. See chamber dryer dobbin hot-floor mangle tunnel dryer. Dryer Scum. See scum. 

Gooseneck. See under bustle pipe. Goskar Dryer. A chamber dryer for bricks and tiles designed by T. A. 

Waste-heat Dryer. A dryer for clayware that derives its heat from the cooling ware in the kilns. Such dryers are common in the brick industry and, even though the fuel consumption in the kilns may be slightly increased, this method of heat utilization results in an overall economy in fuel. Hot-floors, chamber dryers or tunnel dryers can be operated on this principle and the necessary heat can be derived from intermittent, annular or tunnel kilns. 

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