Document g2KwBLkYLqmoYEoKM8BOvZe3L

886 '. CHAPTER 51 ' - 1948 Guide ' ' Table 2. r Conversion Factors for Water Analyses - r.: To Convert Grains per U. S. gallon................................ Grains per Imperial gallon . ,:.:.. ..,....., :................ Grams per liter........ ....:................ Mg per liter. ......__:..................................... -TM--T" Into , PP.m - PPm ' : Ppm. . ppm . '. Multiply by .17 " 14M 1000 I waters," 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 in to 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, synthesize chlorophyll for the production of sugar, and the fungi which lack chlorophyll and. must therefore secure already synthesized carbo hydrates. All Thallophyta are of universal distribution and many of them are slime forming. Of the five divisions of algae,- only three (the green, the blue-green, and the. diatoms) are found in fresh water. Of the five divisions 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 afe 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 for .the,analysis of deposits on surfaces Haying the temperature 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 Phyla Algae Fungi Table-3. Principal Slime Formers Rough Division of Phyla /Single-celled, ^metimesiorming.sliniy sheets.. . Many.celled iij either sheets or fronds. ... . Bacteria (Schizomycetes) frequently forming slimy surface coatings. Slime Molds (Myxomycetes) forming slimy sheets as one stage of tfieir life history. " ; Sac /ting* (Asconiyfcetes) of which one division, the yeasts, occasion- ially.form slimy aggregates.1 - : : The alga-like fungi (JPhycomycetesj and the stalked fungi (Basidomycetes) rarely form slimes but their filaments may hold together the slimes of other organisms. Gorrosion and Water Formed Deposits Caused and Prevention 887. .Table,4. . Plant Water Supply Examination WATER, :. SUPPLY--' S-water isproducWg a SAMpiJE--; T*if*, Compressor n the mtfleeat-chilling,rfotohme,s-heTlhl ea-nsdteiruilbeesacom'tDfdlee-nh^nrttr<pif: ^Jth.l6posit.and the balance with circulating water. No preservative was added^-^iH at tim'e-of collection w^s-714. > ` ", ANALYSIS REQUIRED-- , MACROSCOPIC ; ! : ''BACTERIOLOGICAL |V| MICROSCOPIC1 , : ' [_Vj [Vj ' > ? ORGANIC CONTENT [Vj : .' PROBLEM-- ,, ?r.e<^n^12 Compressor has head pressure about 10# higher than hai?belnltSl!2JS?UOni, with6ui chane water temperature. "Deposits '' h^t.exch^ger surfaces.. It is desired to knowrhe these deposits and if they are the cause of this increased head MACROSCOPIC Heavy brown flocculent material settles rapidly in Clearwater/ dH--7 3` EXAMINATION-- Odor--woody, mouldy. MICROSCOPIC " EXAMINATION-- rariw na<7^S',A.TER 1 Iinduded)ACTERIA--prfuse White crystals. amount--brown. growth of crenothrix--(Photo usually CULTURAL SABOURAUD'S AGAR EXAMINATION-^ ' usu^y i!Side^SitiVe rod With mucoid. sheathi'.OPhoto . 2. Shog gram negatiye"cOctibaqiM (Photo usually included). TOTAL COUNT 100.000 organism/cc; ORGANIC CONTENT (by WEIGHT, DRY BASIS)--60% DISCUSSION-- ' . T^,KP^ce of ?ommon slime-forming organisms in the deposit combined XL1*, ^'?h.?rg"ic "ntent indicates that the deposit is bacterial S?min *u'9nwould be caused by such a deposit ngm' Jnd^on-ta-rousm?,ais W'th Crenothrig- "" corrosion of both ferrous RF.COM- : - ;'-t' MENDATIONS-- r^irSSSS112?/hd,tih'af the water WireatM at- the suction side of the deep zsk cUoTrSs , .treatmentcanbe scheduled on-.an intermittent-basis. - .. > ..................____ _______.__ .uuw, uo in oicaiii couuensmg equipment, pro ducing condensate or return water. /" ; ., -y.In .the heating and ventilating field,,, the. biological, characteristi.es,of condensates are likely to be of concern only where the.cpndensate.is used as-cooling watpr in recirculating systems. The.del.eterious.gas contents of condensates, however, very often create serious corrosion.troubles. The data.mTAble: 5 typify the chemical composition of the!atmosphere in .rural, and metroplitan areas, and of-stack gases when-various typestof common fuels are used. The curves;in Fig., 1 disclose the-,solubility, of the major deleterious gases present-in such-atmospheres .in otherwise pure water, ,when..the partial pressure of the. gas is. one pound per square inch absolute. , `...... .' . .. The most common deleterious gases entrained,by steam1 are oxygen and