Document 2Re4dzQozNvkvzNex3b9nDNMb

CHAPTER 29 1954 Guide 650 2. UNIT Stf. a MCoNsoMfUQ*. OF Process Equipment^ Table .Kitchen Appliances (exclusive op water heating) Consumption, ,. Lb per Hr Stock And vegetable kettles-(per 5 gal) Vegetable steamers (per compartment) Steam tables (per sq ft) Bain-Maries (per sq it) Coffee urns (per gal) Water urns (per gal) Soup warmers (30 X 30 X 28 in.) Egg boilers (3 compartments) Clam, lobster, and potato steamers (per compartment) Oyster pots Plate and cup warmers (per 20 cu ft) Food-warming ovens (per 20 cu ft) Silver burnisher and washersDishwashers (per tray) , 20.0 40.0 1.7 3.4 -3.4 5.0 100.0 15.0 40.0 18.0 35.0 35.0 69.0 60.0 7-20 7-20 7-20 7-20 7-20 7-20 7-20 '7-20 7-20 7-20 7-20 7-20 7-20 7-20. Laundry Equipment Tumblers 40 X 94 in. 30 X 36 in. Washers, (per gal water heated) Flatwork ironers, 100 to 120 in. chest type (per roll) 50 to 100 in. cylinder type (per machine) Standard presses Large shirt body presses Cuff and neckband presses Sleevera Steam-electric irons Woolen pressing machines Large--electric vacuum Small--electric vacuum Large--steam vacuum Small--steam vacuum Feather cleaning and sterilizing 15 pillows per hr Hospital Equipment Sterilizers, for bottles or pasteurization (per bottle) Sterilizers, for water, (per gal) Sterilizers, for instruments and utensils, 8 X 9 X 18 in., water depth 3) in. 9 X 10 X 20 in., water depth 3)4 in. 10 X 12 X 22 in., water depth 4 in. 12 X 16 X 24 in., water depth 4 in. 10 X 12 X 36 in., water depth 4 in. 16 X 15 X 20 in., water depth 10 in. 20 X 20 X 24 in., water depth 24 in. Sterilizers, lor instruments @ 240-250 F, 12X20 in. 14 X 22 in. 360 225 60 60-120 105 190 15 12 8 25 12 35 20 175 1 12 27 30 39 60 66 92 144 48 60 72 100 100 15-100 100 100 100 100 100 100 100 65 65 65 65 100 40 40 40 40 40 40 40. 40 40 40 40 40 District Heating 651 Table 2. Unit,Steam Consumption of Process Equipment (Concluded). Hospital Equipment (continued) Consumption, Lb per Hb Pressure, PSIG Sterilizers, for surgical supplies 10 x 20 in. 12 X 20 in. 14 X 22 in. 16 X 24 in. 16 X .36 in. 10 40 22 40 . 28 40 38 40 54 40 20 X 28 in. 20 X 36 in. 20 X 48 in. 20 X 60 in. 60 40 78 40 98 40 124 40 Sterilizers, (autoclave) (240-250 F) 15.5 X 24 in. 17.5X26 in. 21.5 X 30 in. 24 X 36 in. 24 40 32 40 40 40 40 Disinfector, mattress 30 X 42 X 84 in. 60 X 66 X 108 in. Blanket warmers 18 X 24 X 72 in. ----- ---------- 42 35-60 318 35-60 4 35-60 * From District Heating Handbook (National District Heating Association, Third Edition, 1951). D The above figures represent approximate operating conditions after warm-up period. upoa the value of the service to the consumer, and it must be between these two limits. District heating rates should be designed to produce a sufficient return on the investment regardless of weather conditions, al though existing rate schedules do not always conform to this principle Lastly, the rate schedule must be reasonably simple and understandable. Glossary of Rate Terms Load Factor. The ratio, in percent, of the average hourly load to the maximum hourly load. This is usually based on a one-year period, but may be applied to any specified period. Demand Factor. The relation between the connected radiator surface, or required radiator surface, and the demand of the particular installation. It varies from 0.25 to 0.3 lb per (hr) (sq ft of surface). Diversity Factor. The ratio of the sum of the individual demands of a number of buildings to the actual composite demand of the group. Types of Rates The various types of rates to be found in use in district heating systems are: 1. Slraighl-Line Meier Rate. The price charged per unit is constant, and the conBurner pays in direct proportion to his consumption without considering the dif ference in costs of supplying the individual customers. 2. Block Meier Rate. The pounds of steam consumed by a customer are divided mto blocks of thousands of pounds each, and lower rates are charged for each suc cessive block consumed. This type of charge predominates in steam heating rate schedules, having the advantage of proportioning the bill according to the consumpbon and the cost of service. It has the disadvantage of not discriminating between