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132 Chapter 4 Quantities of Water and Wastewater Flows
Table 4.8 Water Percentage of Total Water Intake Consumed by Industry

Percent of Percent of
Industry Intake Industry Intake
Automobile 6.2 Meat 3.2
Beet sugar 10.5 Petroleum 7.2
Chemicals 5.9 Poultry processing 5.3
Coal preparation 18.2 Pulp and paper 4.3
Corn and wheat milling 20.6 Salt 27.6
Distillation 10.4 Soap and detergents 8.5
Food processing 33.6 Steel 7.3
Machinery 21.4 Sugar, cane 15.9
Textiles 6.7

To draw comparisons between the water uses of different industries and of plants within
the same industrial category, it is customary to express plant or process use in volumes of
water—gallons, for instance—per unit of production (Table 4.9). For the chemical industry,
however, this may not be meaningful, because of the diversity of chemicals produced.
Rising water use can be arrested by conserving plant supplies and introducing effi-
cient processes and operations. Most important, perhaps, are the economies of multiple
reuse through countercurrent rinsing of products, recirculation of cooling and condensing
waters, and reuse of otherwise spent water for secondary purposes after their partial purifi-
cation or reunification.

Table 4.9 Water Requirements of Selected Industries
Industry Unity of Production Gal per Unit
Food products
Beet sugar ton of beets 7,000 1
Beverage alcohol Proof gal 125–170
Meat 1,000 lb live weight 600–3,500 2
Vegetables, canned Case 3–250
Manufactured products
Automobiles Vehicle 10,000
Cotton goods 1,000 lb 20,000–100,000
2
Leather 1,000 ft of hide 200–64,000
Paper ton 2,000–100,000
Paper pulp ton 4,000–60,000
Mineral products
Aluminum (electrolytic smelting) ton 56,000 (max)
Copper
Smelting ton 10,000 3
Refining ton 4,000
Fabricating ton 200–1,000
Petroleum Barrel of crude oil 800–3,000 4
Steel ton 1,500–50,000
1
Includes 2,600 gal (9,841 L) of flume water and 2,000 gal (7,570 L) of barometric condenser water.
2
Lower values for slaughterhouses; higher for slaughtering and packing.
3
Total, including recycled water; water consumed is 1,400 gal (5,390 L).
4
Total, including recycled water; water consumed is 30 to 60 gal (113.55 to 227.1 L).
2
2
Conversion factors: 1 gal 3.785 L; 1 ton 2,000 lb 0.9072 metric ton; 1 lb 0.4536 kg; 1 ft 0.0929 m ;
3
3
1 barrel 5.615 ft 0.159 m 42 gal.