Standards for Hygienic Purity of Public Water Supplies. - Industrial

---

95, 692) that the production of phosphate rock in Florida for 1912 was 2,579,865long tons, as compared with 2,494,572tons in 1911. The production of hard rock in 1912was j36,379 tons, as compared with 474,094tons for the previous year. The output of pebble phosphate in 1912was 2,043,486tons as compared with 2,020,478tons in 1911. Thirty companies in all were engaged in mining phosphate in Florida in 1912: of these, 1 4mined hard-rock phosphate and 16 mined pebble phosphate. The foreign shipments during 1912amounted to 1,203,oojtons, while I,Z19,927 tons were consigned for domestic shipment. Hard-rock phosphate sold a t the mines a t about $6.00 per ton, while pebble phosphate sold a t the mines a t %.jj to $4.50 pcr ton, depending upon the grade. THE PRODUCTION OF CYANAMIDE 20% Cyanamide in 1:IRZrl

IVORKS

tons

1‘117

1912

(prohahie)

7,500

7,500

8,000 15,000

12,000

l5,ooo

45,000

24,000

5 2 , on0

Societk des Produits XzotPs. ., . . . . . .

... ,. .

.

Notre-Dame de Iiriancon, Sal-oie, France. . Martigny, Talais, Switzerland . . , . . . . . . . . , B ayerische Stickstoffwerke Trostberg. Germany., . , -4ktien Gesellschaft fur Stickstoff-dunger. . . . . . . 1Vesteregeln. Knapsack. Germany. . . . . . . , . . Northwestern Cyanamide c o . . . . . . . . . . , . . . . . . . . Odda, Norway.. , . . . . . . hlby, Sweden. . . . . . . Meraker, Sweden.. , , , . , Stockholm Superphosphate. , . , . . . . . . . . . , . Johannesberg. Sweden, . StL. per la Fabricazzione dei prodotti Azotati. . . . Terni. Perouse, I t a l y . . . SocietC Piemontaise de Carbure de Calcium. . . St. Marcel Vallee d’Aoste, Italy. . . . . . , . , . . Sth. Sufid Societe d’Utilisation des forces hydrauliques de la Dalmatie.. . , . . . . . , . . . . . . Sebenice, Dalmatia.. . . . Almissa, Dalmatia. . . . , American Cyanamide Co ... h-iagara Falls, O n t . . . . Alabama plant. . , . , . , Societe Japonaise pour la Cyanamide. . . . . . . . . . . . Osaka, J a p a n . . , . . , . . . . , ,

..

Total production.. . ,

15,000

15,000

15,000

, ,

.,

12,000

, ,

..

15,000

24.000

2 4 , onn

3,500

3.500

5,000

5,000

,

.,

24,000

24,000

. .,

24,000

12,000

12,000

153,000

260.000

THE “FITTING-INJECTOR DEA”

X Hannoter-Linden, Germany, firm has placed on the market an injector vhich is said to perform the work of other types of injectors, while the parts may be replaced during operation It is said to be particularly suitable for the transportation of liquids containing suspended particles and alkaline liquors it is in use in Germany in plants for leache ing sodium a n d barium sulfides The construction IS shown in the accompanqing figure -1a is a cross piece b I$ the steamentry c IS a nozzle for I pressure rntry d is a screv plug for cleaning purposcs and e is a suction tube d

I

,

ELECTROLYSIS FROM STRAY ELECTRIC CURRENTS The matter of electrolysis from stray electric currents is onc of importance to the chemical, gas and municipal engineer, especially since Gardner (1.Frank.. Inst., 1908, 459) has shown. in an investigation of the effect of a n electric current on the speed of the corrosion of steel plate. that in every case the action seemed to have been about doubled in its intensity by the passage of thc current. The remedies brought out in a very recent paper bv Ganz ( A m . Gas Light J . , 98,No. 1 2 , 190) are therefore pertinent, and accordingly h k conclusions are given a t some length. Experience shows that where there is serious trouble from electrolysis caused by large stray currents leaking from street railways, the bulk of this trouble is due to defective rail bonding, to ground connections from the negative bus-bar, and to lack of return feeders to carry the current back from the rails to the power station. While stray currents can only be entirely eliminated by insulating the return circuit by theuseof adoubletrollcy, either overhead or in conduit, i t is nevertheless a fact, not generally appreciated, that where large stray currents exist, due to the above-mentioned causes, these can always be reduced to a small fraction of their present value by removing all ground connections of the negative bus-bar, and installing insulated return feeders proportioned for equal drop from radially disposed points in the track system located a t some distance from the power station. By this method, the rails are drained of current, and any desired part of the voltage drop can be removed from the rails and transferred to insulated conductors from which the currents can not leak. I n Europe such radial insulated return feeders, for bringing the current back from the rails to the power station, are made necessary by regulations limiting the allowable drop in voltage in the rails; and, in most cases, such installation of insulated return feeders have substantially removed serious trouble from electrolysis. This system of minimizing stray currents by means of radially disposed insulated return feeders has also lately been installed in a number of American cities, and the method is becoming recognized by railway engineers as by far the best. This system removes the root of the trouble, by draining the rails of current and removing the voltage drop from the rails, and consequently prevents any substantial leakage of current through the ground; it is, therefore, correct in principle. The objection to such a method has been the expense of the system, but Ganz states that this is not the case. The fact is, he continues, that in many American railways there is practically no installation of negative feeders, and that railway companies are often unwilling to install even a moderate amount of return feeder copper. Ganz concludes by remarking that in order to effectively install and maintain an adequate return feeder system that will reduce stray currents on underground piping systems to reasonably small values, it is essential that pipe-owning companies cooperate with railroad companies by affording them access to their pipes for making the necessary measurements, etc. STANDARDS FOR HYGIENIC PURITY OF PUBLIC WATER SUPPLIES J. %’. Ellms (Eng. Record, 67, N o . 1 1 , 293) suggests the appointment of delegates from each of the large engineering societies, materir orks and sanitary associations to formulate a plan of procedure for preparing standards of purity for public water supplies. It is proposed that these delegates work in conjunction xvith any state or federal committee. Among the matters which should be discussed are the following: (I)What diseases may be legitimately regarded as water borne. This involves a consideration of the Mills-Reincke phenomenon and the Hazen theorem (Sedgwick-MacNutt), and the ideas of chronic intestinal tract infection advanced by Hill and lyhitcomb. It means a careful analysis of all available

T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y

May, I 9 I 3

and reliable vital statistics of those communities having impure water supplies as well as those having pure supplies. ( 2 ) A clear definition of what really constitutes a pure drinking water. This means that much light is needed upon the relative numbers and kinds of bacteria, the nature and amount of the organic and inorganic matter which may be present in public r a t e r supplies, and their significance in the causation of disease. I t necessitates an examination of the available bacteriological and chemical data of public water supplies, and a classification of the same in relation to vital statistics. (3) The selection of the maximum limits for the numbers and kinds of bacteria in a drinking water, and the permissible amounts of organic and inorganic matter which such a water m a y contain. ~ _ _ STANDARDS FOR SEWAGE AND SEWAGE EFFLUENTS The Eighth Report of the Royal Commission on Sewage Disposal (Suture, 91, 61) deals with the important question of standards and tests for sewage and sewage effluents discharging into rivers and streams. The Commissioners had earlier indicated the desirability of fixing a legal standard for sewage effluents, and proposed that such a standard should be based upon ( I ) suspended solids and ( 2 ) absorption of dissolved oxygen. Their contention then was that the two tests should be taken separately, and they suggested three parts per IOO,OOO as the limit of suspended solids, and that the effluent after removal of its suspended solids should not absorb more than 0.5, I and 1 . 5 parts dissolved oxygen pel- IOO,OOO after one day’s, two days’, and five days’ incubation a t 6 5 O F., respectively. In their present Report the Commissioners recognize the difficulty of the separation of the suspended solids, and finally recommend the following as the normal legal standard, namely: 3 parts per 100,ooo of suspended solids, and, including its suspended solids, the effluent shall not absorb more than 2 parts dissolved oxygen per IOO,OOO after five days’ incubation a t 6 5 O F. I n the opinion of the Commissioners, the legal standard should be a variable one, dependent upon the conditions a t the outfall, i. e . , the condition of the river or stream receiving the effluent and the relation of the volume of sewage effluent to river water. The Commissioners state that their experience leads them to think that if the dilution while not falling below 150 volumes does not exceed 300 volumes, the dissolved oxygen test may be omitted and the standard for suspended solids fixed a t 6 parts per IOO,OOO; and if the dilution while not falling below 300 volumes does not exceed 500, the standard for suspended solids may be further relaxed to 15 parts per IOO,OOO. With a dilution of more than joo volumes all tests might be dispensed with and crude sewage discharged, subject to such conditions as to provision of screens or detritus tanks as might appear necessary to the central authority. ~

___

“HARDENED” OILS A . W. Knapp (Analyst, 38, No. 444, 1 0 2 ) described three fats which were obtained from a clear cottonseed oil. They were hardened by hydrogen with the aid of difierent catalysts, and gave the following results upon examination: Percentage of catalyst CATALYST in oil h-ickel. , . . . . . . . 1.00 Platinum.. . , , 0 . 1 0 Palladium. ., , . 0 . 0 6

. .

Character of product Hard Hard Brittle

Butyrorefraction (corrected t o 40’ C.) 45.7 47.8 45.5

Melting point. C. 49 46 52

The keeping properties of these “hardened” oils were said to be remarkably good. The fats described had been prepared for nearly a year and a half, had often been exposed to damp air, and yet showed no signs of rancidity. The free acidity (0.70 per cent. as oleic acid) had not appreciably changed.

427

Knapp states that hardened oils give soaps which are good in color, but deficient in lathering properties. H e does not consider that any objection will be raised to their admixture with other fats for soap-making. However, he points out that their use in the preparation of edible fats is more open to question, and that in the interests of public health, certain investigations should first be made to show: ( I ) That no harmful substances are procluced by the chemical changes in the fatty glycerides and unsaponifiable matter. (2)*That a high percentage of tristearin does not render the fat indigestible. ( 3 ) That traces of nickel, from I to I O parts per million, are not harmful. H e considers that there is perhaps little to be feared from objectionable substances in the hydrogen used, as the majority of such substances would poison the catalyst. ___WATER GAS TAR AS A WOOD PRESERVATIVE *4t the Fifth Annual Meeting of the Indiana Gas Association, Indianapolis, Ind., March 1 2 , 1913, F. C. Mathers presented the results of some experiments on the preservation of timber with water gas tar. The United States Forest Service has conducted many experiments on the creosoting of wood, but none of the Bulletins issued gives results with water gas tar, although, Mathers stated, fence posts, etc., could be treated with this tar which costs only about 3 cents per gallon as compared to 15 cents per gallon for coal tar creosote. Mathers found that water gas tar would re?der timber water-proof, although it was less strongly antiseptic than coal t a r creosote; and timber exposed t o the weather became very much more resistant to decay after receiving treatment with water gas tar. KINDOF

WOOD

TREATED

Per cent. of tar absorbed

Sycamore(a) . . . . . . . . . . . Black walnut(b). . . . , . Sugar m a p l e . , ..

. . . .. . ...

Gallons of tar for one post

Cost of tar per post in cents

65

‘1.0

168

3 .6 I .9

12 11 6

.). . 2

13

:? , 4 ..

7 ..

39

( a ) The best wood to treat, owing to the reads absorption. ( b ) Partly decayed, hence large absorption.

The table above gives the percentage by weight of tar absorbed, the number of gallons required for a post 7 feet 6 inches long and 4 inches in diameter a t the two ends, and the value of the tar in each post, assuming the cost of the tar to be 3 cents per gallon. One gallon of water gas tar was found to weigh 8.9 pounds. (.kt the Fourteenth Annual Convention of the American Railway Engineering Association, Chicago, March 18, 1913, a committee reported t h a t the use of water gas creosote x a s limited but increasing, and t h a t there was a growing sentiment in favor of mixing this with coal tar creosote. The principal objection to the use of water gas creosote seems to have been its unauthorized use in the adulteration of coal t a r creosote.-W. A. H.)

PULP AND OTHER PRODUCTS FROM WASTE RESINOUS WOODS I t has been demonstrated, both in the laboratory and in the mill, that paper of good quality can be made from pine wood (Bureau of Chemistry, Circular 41 and Bulletin 144). Veitch and Merrill (Bureau of Chemistry, Bulletin 159, 1913) now consider that it is feasible to combine three well developed chemical industries-paper making, wood distillation (in a modified form), and the manufacture of rosin oils-and thus to obtain from a single raw material, waste resinous wood, practically all the valuable constituents. The country’s sources of paper, turpentine, rosin oils, and wood alcohol can be greatly augmented and the injury to forests by fire and insects materially reduced by the utilization of this wood. The approximate yield for 4)000 pounds of cord air-dry wood