Truck driers

Tray, Truck, and Tunnel Driers In order to accelerate drying, the closet is factory-built with tight walls. It forms a box, and the air is passed by means of a fan over a radiator or over finned tubes and then over the trays. A portion of the air escapes at the discharge opening the remainder is reheated and recirculated. An amount of new air equivalent to the volume discharged is admitted at the fan. Secondary heating tubes are placed in the path of the air to restore their temperature and heat content. In the tray drier, shallow pans 2 ft by 3 ft by 2 in. deep, for example, are placed on a rack, forming part of the drier. In the truck drier, the rack is on wheels, and the whole may be wheeled in and out of the drier. There may be one or several trucks to each drier, and each truck may have twelve, sixteen or more levels for trays. 

Compartment driers are closets or even rooms in which the material is spread on trays or in shallow pans. The operation is often discontinuous in order to make it continuous, the pans may be placed on trucks traveling on rails, and these are pushed through a tunnel in which warm air circulates. Belt driers and chain driers have similar goals. 

D. aj-C,Hj-0 CH2-COOH. Umiled laboratory tests indicate that dilute aqueous solutions of 2. 4-D caused mild attack of 3003 alloy at ambient temperature. 2, 4-D has been handled in aluminum alloy sprayers and piping. CAUTION. See "Hak>-genated Hydrocarbons. Sec also Ref (3) p. 127. DAIRY PRODUCTS. Aluminum allays have been used for milk pails, milk cans, storage tanks, truck tankers, pasteurizers, coolers, butter chums aud tubs, foil hoods, and powdered milk driers. See also Ref (3) p. 204. (6) p. 11. 

VINYL ACETATE. CHj -COO -CH -CHj. Aluminum alloy equipment has been used for polymerization kettles, driers, containers and tank trucks in the production and handling of vinyl acetate. See also Ref (3) p. 136, (7) p. 193. 

For adiabatic operation, 0 = 0, and if heat is added within the drier to an extent greater than the heat losses, Q is negative. If the solid is carried on trucks or other support, the sensible heat of the support should also be included in the balance. Obvious changes in the equations can be made for parallel-flow driers. 

A continuous countercurrent hot-air turmel drier is to be designed to dry a filter-press cake of coarse crystals of an inorganic substance, insoluble in water. The filter-press cake will be placed on trays 1.0 m long by 0.9 m wide by 25 mm, 20 trays to-a truck, with 50 nun between trays. The tutmel drier will have a cross section 2 m high by 1 m wide. The trays have a reinforced screen bottom, so that drying takes place from both top and bottom of each tray. Production permits introducing one... 

TDI trucks are equipped for top-unloading only and have compressors and air driers to maintain product integrity. Pumps can be made available upon request. Tanks are constructed of stainless steel all are insulated and have exterior heating coils. 

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