Dryers ovens

Hot Surfaces. The incomplete immersion of hot metal in quenching baths, the contact of flammable vapors and hot combustion chambers, hot dryers, ovens, boilers, ducts and steam lines all are frequent causes of flammable vapor fires. Care should be taken that material whose auto-ignition point is lower than the temperature sometimes reached by operating equipment be kept at a safe distance from such equipment. 

Microwave radiation is emitted by dryers, ovens, and heaters normally used in the home. The high-power radars used for military purposes, communication equipment, alarm systems, and signal generators are other sources of microwave radiation. The low-power microwave radiation can cause heating and skin redness whereas high-power microwave radiation can cause inductive heating of metals and induced currents that can produce electric spark. Containers with flammable materials may catch fire if they are placed in the microwave fields. Rings, watches, metal bands, keys, and similar objects worn or carried by a person in such a field can be heated vmtil they burn the bearers. 

Equally small are the efficiencies of many industrial processes, particularly those involving low-temperature drying of materials such as food, textiles, or paper. This can be seen from an analysis of the efficiency of a dryer oven used to remove moisture from tobacco slurry. In this process, natural gas fuel is... 

Continuous dryers, ovens, incinerators, and furnaces take any of a variety of forms such as rotary drum, tower, shaft, tunnel oven, multihearth (Herreshoff) kiln, and fluidized bed. As with all continuous furnaces, their design is very dependent on how the load(s) can be moved through the furnace (or occasionally, how the furnace can be moved over the loads). 

The reader should review section 3.8.1 on batch ovens and low-temperature batch furnaces because many of the ideas discussed there also apply to continuous dryers, ovens, and furnaces. Dryers and drying ovens usually release large quantities of water vapor or of solvents, the accumulation of which can have at least two bad effects (1) an explosion hazard with flammable solvents and (2) a reduced rate of drying (mass transfer) with either water or solvent drying. Tables B.3 and B.4 of reference 51 give heat requirements for drying. 

Karl Fischer titration, infrared dryer, oven... 

Eactory Mutual Engineering Corp. 1151 Boston-Providence Turnpike Norwood, Mass. 02062 Standards for safety equipment, safeguards for flammable Hquids, gases, dusts, industrial ovens, dryers, and for protection of buddings from wind and other natural ha2ards. 

Nonstabilized foams are referred to as froths froth-bonded fabrics are similar in properties to some saturation-bonded nonwovens. Typical foams used as nonwoven binder solutions have a consistency similar to shaving cream. AppHcation methods include knife-edge layering onto a horizontal web surface followed by vacuum penetration, and saturation and penetration of a vertical web surface using a horizontal-nip pad. Drying and curing is carried out in ovens, dmm dryers, or steam cans. 

Catalysis is utilized in the majority of new paper filter cure ovens as part of the oven recirculation/bumer system which is designed to keep the oven interior free of condensed resins and provide an exhaust without opacity or odor. The apphcation of catalytic fume control to the exhaust of paper-impregnation dryers permits a net fuel saving by oxidation of easy-to-bum methyl or isopropyl alcohol, or both, at adequate concentrations to achieve a 110—220°C exotherm. 

Performance Data for Direct-Heat Tray Dryers A standard two-truck diyer is illustrated in Fig. 12-48. Adjustable baffles or a perforated distribution plate is normally employed to develop 0.3 to 1.3 cm of water-pressure drop at the wall through which air enters the truck enclosure. This will enhance the uniformity of air distribution, from top to bottom, among the trays. In three (or more) truck ovens, air-reheat coils may be placed between trucks if the evaporative load is high. Means for reversing air-flow direction may also be provided in multiple-truck units. 

An oven can be used instead of an oil bath. If the amount of polymer to be post-condensed is large, a tumble dryer (rotavapor apparatus) or moving bed reactor can be used. 

Figure 10 Swelling of PHEMA in water. ( ) Isotropically dried in a vacuum oven ( ) anisotropically dried in a gel dryer (-----) Fickian curve. (Adapted from Ref. 136.)...

Chemical flowshops are widely used in industry for the medium-scale synthesis of chemicals. In a flowshop, a number of different physical units, such as reactor vessels, ovens, dryers, and distillation columns are placed in a serial, or largely serial, arrangement. Rather than being devoted to the preparation of a single chemical, many different chemicals are synthesized one after another in a flowshop by feeding in the appropriate precursors and reagents as the intermediates pass through most or all of the units. This mode of operation is an effective use of the physical plant because no part... 

Built-in ovens, and dryers, each somewhat more than 3 million units... 

The degree to which European households are equipped with appliances varies - the saturation level being highest in Central and Northern Europe, somewhat lower in Southern Europe and still lower in Eastern Europe. The average saturation level for some larger appliance families is shown in Fig. 2.5. For washing machines, cookers and refrigerators, a saturation of more than 90% has been achieved, around 50% for microwave ovens or freezers, and only 25% for dryers. 

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