Agroindustrial project analysi

Table A-1 (continued)Mode and scaleDryer of operation 1977 capital cost' 1977 operating cost' CommentDrum' Continuous operation $44,750 for 1½/2 Same as for spray dry- In general, drum dryers produce prodforsmall- to medium- tons, $70,000 for ing (above); $0.012-.04 ucts that are inferior in organolepticscale drying of fluids, 5 tons, $100,000 per pound raw ma- and nutritive quality to spray-driedslurries, and pastes; for 8 tons, terial, $0.016-.053 per because of scorching and other probbestfor one product $228,000 for 32 pound water removed lems; drum-dried milk, however, istons daily'often preferred over spray-dried milkfor candy making (because of higherfree fat content and heat-induced stabilizationagainst oxidation) and forsausage making (because of higher0 water absorption); because of the flakycharacteristics it gives, drum drying isstill extensively used to make potatoflakes and similar products; drum dryingusually involves much smallercapital investment than spray dryingthismay be advantageous when thedrying operation is small, seasonal, ordependent on raw materials whoseavailability is not secureBin Batch operation for VZ-½3 that of a V2_1Z/3 that of a cabinet During finish drying in bins, moisturefinish drying (that is, cabinet dryer of dryer, based on cost is redistributed among the almost dryto reduce moisture similar size per pound water re- products, and, at the same time, mostfrom 10 to 3 percent) moved moisture is removed; this lowering and