Document G5Ymx0VRydK3bDR3xX6bK6vQr

j ; ;ri ' i- 1{? i*'1 " ` '1! ill ' J!i i' " 982 CHAPTER 43 1956 Guide CLASSIFICATION AND CHARACTERISTICS OF WATER For industrial use there is no accepted conventional classification of water. Rather, each industry usually develops a body of ideas applicable to its own water, problems.4 For heating and ventilating engineers, it is perhaps most convenient to distinguish between mineralized waters and condensates. Mineralized Waters All the waters found in streams, wells, lakes, and the ocean are min eralized. The same is true of all municipal supplies even though they may have been treated. For a given area, ground waters are likely to be more highly mineralized than are surface waters. Conversely, surface waters Table 1. Mineral Analyses Typifying Composition of Waters Available and Used Industrially in the USA Substance Unit Location ob ABEAa,b 0) (2) (3) (4) (5) . (6) (7) (8) (9) Potassium........................................... SiOt Fe Ca Mg Na K HsCoOi Cl NO* Non-Carbonate Hardness. ............ CaCO* CaSO< 2 0 6 1 2 1 14 10 2 1 31 12 5 6 12 00 5 36 28 67 11 13. 119 2 22 10 13 0 66 165 11 98 7 18 37 10 10 62 92 18 34 44 8 1 202 339 135 84 13 10 2 13 426 434 165 287 40 58 .9 0. 96 27 183 18 22 0 3 2 215 10 334 549 121 11 280 22 01 983 564 274 8 54 0 14 2 155 400 46 1.300 78 11,000 3 400 210 . 150 389 2,700 117 19,000 3 948 35,000 172 125 295 5,900 a All values are parts per million of the unit cited to nearest whole number (see Reference 5). b Numbers indicate location or area as follows: . (1) Catskill supply--New York City (6) Well Water--Maywood, Illinois-- (2) Swamp Water (Colored) Black Creek, Middleburg, Florida 2090 ft. (3) Niagara River (Filtered) Niagara Falls, New York (7) Well Water--Smithfield, Va.--330 ft. (4) Missouri River (Untreated) Average (8) Well Water--Rosewell, N. Mexico (5) Well Waters--Public Supply--Dayton, Ohio--30-60 ft. (9) Ocean Water--Average are more likely to be contaminated with municipal sewage and trade wastes. Virtually all mineralized waters also contain biological organisms. Mineralogical Characteristics. The character and amount of extraneous inorganic materials--including deleterious gases--dissolved and sus pended therein, describe the mineralogical characteristics of any water. Revealing such information is the function of a mineralogical chemical analysis. The analyses in Table 1 disclose the composition of the public water supplies used by about 45 percent of the total population of the cities, in the United States, having more than 20,000 inhabitants.6 All values recorded are in terms of parts per million.* This is the approved standard terminology for reporting the results of mineral analyses.6 Values reported in the other terms commonly used may be converted into the standard form by using the factors listed in Table 2. Data for dissolved gases or pH values have been omitted in Table 1 because even waters of the same mineral contents may vary widely in these respects. Unpolluted natural waters usually have pH values within the range 5 to 8, depending upon their free COi contents. Polluted waters, * Parts per million are hereinafter abbreviated ppm. A pari per million signifies a unit weight of mate rial per million unit weights of the solution. Corrison and Water Formed Deposits, Causes and Prevention 983 Table 2. Conversion Factors fob Water Analyses TO CONVKBT Into Multiply by Grains per U. S. gallon..................................... Grains per Imperial gallon............... ............. Grams per liter............................... .............. Mg per. liter......... ........................................... ppm ppm ppm ppm 17 14M 1000 1 which include those derived from wells or swamps in marshy ground, may have pH values well below 5. Biological Characteristics. The slime-forming organisms are mostly lower plants, grouped by botanists into the phylum thallophyta. This group is distinguished by the absence of leaves, roots, or stems from the mosses, ferns, and seed plants which comprise the three other phyla of the plant kingdom. The thallophyta (see Table 3) are divided into algae, which can syn thesize 'chlorophyll for the production of sugar, and the fungi which lack chlorophyll, and must therefore secure already synthesized carbohydrates. All thallophyta are of universal distribution and many of them are slime formirig. Of the five divisions of algae, only three (the green, the blue-green, and the diatoms) are found in fresh water. Of the five di visions of fungi, all may occur in fresh water, the principal slime formers being indicated in Table 3. The methods of analysis commonly used in the sanitary examination of a water have, as their principal object, to identify and count pathogens. Most slime-forming organisms are not pathogens. When a water is subjected to a biochemical analysis for the purpose of evaluating its slime producing characteristics, tests, widely different from sanitary bacterio logical tests, must be made. Tests upon the water itself are seldom satis factory, and true indications of the sliming characteristics of a water can only be determined by the analysis of deposits on surfaces having a tem perature close to the temperature of the final design equipment. The results of such a test are commonly reported in the manner illustrated in Table 4. Condensates All condensates result from the chilling of water vapor. Such chilling may result from natural causes, thus producing dews, sweats, rain, and snow, or from artificial causes, as in steam condensing equipment, pro ducing condensate or return water. Table 3. Principal Slime Formers Phyla Rough Division op Phyla Algae Fungi Single celled, sometimes forming slimy sheets. Many celled in either sheets or fronds. Bacteria (Schizomycetes) frequently forming slimy surface coatings. Slime Molds (Myxomycetes) forming slimy sheets as one stage of their life history. Sac fungi (Ascomycetes) of which one division, the yeasts, occasion ally form slimy aggregates. The alga-like fungi (Phycomyceies) and the stalked fungi (Basidomycetes) rarely form slimes uut their filaments may hold together the slimes of other organisms.