Apr.,
1914
T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y
ENGLAND'S CHEMICAL TRADE
1912AND I913
C h e m . Zlg., 38 (1914),240 VALUES IN R O U N D THOUSANDS
Imports Sodium compounds Saltpeter Other potassium salts Fertilizers: Basic Bone Guano Chile saltpeter Phosphate a n d rock phosphate Bleaching materials Boracite. borates, borax, etc Sulfur, crude Calcium carbide Chemicais; r . 4 . . .Iceton e, calcium ace t a t e , sulfuric acid China bark Quinine and i t s salts Other drugs Acetic acid Tartaric acid Cream of t a r t a r Glycerine. Crude Distilled Con!-tar products, n o t d j'es Aniline a n d naphthalene Other coal-tar dyestuffs Color extracts Other d>-es hliznrine and anthracene dyes Indigo. .. . natural synthetic Catechu Tanning materials: Bark Gambier Myrobalanen Sumach 1-alonea Other tanning materials Barium sulfate Sickel oxide Red lead W h i t e lead Zinc oxide Pigments, not specified
'
1912 802,000 1,086,000
3,096,000 446,000 I , 0 8 8 , no0
408,000 6,374,000 4,205,000 219,000 936,000 562,000 950,no0
7 ,i70.000 245,000 477,000 6,959,000 419,000 1,118,
oon
1,626,000
1,s l5,OOO
$57,000 / 89,000 7,318,000 2,000 693,000 1 ,396,000 I ,319,000 493,o m 454,000 537,000 1,120,000 684,000 813,000 502,000 i61,OOO 39,000 808,000 585,000 344,on0 1,162,000 2,075,000 4 , 143,000
'
1913 860,000 1,205,000 3,151,000 5 10,000 1,098,000 746,000 7,453,000 4,371,000 172,000 I ,015,000 464,000 1,362,000
8,595,000 290,000 512,000 6,515,000 429,000 1,237,000 1,660,000 1,279,000 423,000 822,000 7,713,000 3,000 642,000 I ,501,000 1,361,000 274,000 383,000 358,000 1,740,000 7 10,000 884,000 416,000 821.000 86,000 752,000 451.000 316,000 1,815,000 2,147,000 4,281,000
Exports Sulfuric acid S a l t (not table salt) Sodium carbonate Sodium bicarbonate Sodium chromate and bichromate Sodium sulfate Caustic soda Soda crystals Other sodium cornpounds Saltpeter Potassium chromate a n d bichromate Other potassium compounds Ammonium chloride Fertilizers: Ammonium sulfate Superphosphate Basic slag (Thomas Meal) Other fertilizers Copper sulfate Bleaching p0wdt.r Tartaric acid Chemicals. misc. Opium Quinine and its .ialts Other drugs Glycerine, crude distilled Petroleum Aniline and toluidine Anthracene Benzene a n d toluene Carbolic acid T a r , crude refined Naphthalene Pitch Creosote, etc. Other coal-tar products Coal-tar dyes Other dyes Barium sulfate White lead Zinc oxide Other pigments
231,000 2,269,000 2,793,000 713,000 259,000 438,000 3,786,000 220,000 764,000 261,000 462,000 469,000 806,000 19,956,000 I , 152,000 I , 172,000 4,166.000 8,597,000 849,000 366,000 14,083,000 332,000 338,000 10,512,000 1,614,000 1,654,000 153,000 162,000 39,000 955,000 1,046,000 91,000 233,000 113,000
5,190,000 2,093,000 I , 174,000 1,022,000 544,000 15,000 2,950,000 294,000 12,927,000
3 13,000 2,363,000 2,818,000 612,000 29 7,000 573,000 3,618,000 226,000 ,89,000 233,000 406,000 655,000 637,000 22,060,000 831,000 1,320,000 4,648,000 8,s14,000 844.000 450,000 13,160,000 62,000 363,000 11,330,000 2,213,000 1,893,000 123,000 145,000 7,000 1,515,000 953,000 89,000 346,000 188,000 5,503,000 2,963,000 1 ,496,000 895,000 527.000 100,000 2,526,000 275,000 13,546,000
ELECTRIC CURRENTS I N CONCRETE The question of the effect of electric currents in concrete and ferro-concrete, of so much importance now, has been investigated experimentally abroad. Among the more recent researches, according to The Engineer (London), 97 (1914),224, are those undertaken in 1 9 1 2 by Dr. Muller at the Technical High School ol' Darmstadt, on behalf of the Deutsche Ausschuss fur Eisenbeton, and the similar experiments made last year by Dr. Kurt Lubowsky a t the Technical High School of Danzig, and described in the Elektrotechnische Zeitschrift of January I and 3, 1914.
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Lubowsky experimented with prismatic blocks, 12 cm. (4.7in.) square, 2 5 cm. (IO in.) high, of various concrete mixtures, some inlaid with iron, which always remained within the blocks covered by 2.5 cm. ( I in.) of concrete. The electrodes were perforated sheets of iron, 7 cm. by 1 1 cm. by I mm. thick, joined to copper leads. The continuous currents were taken from the 220-volt mains, the alternating currents from generators a t 60 periods (maximum), and a transformer. The concrete blocks were stored in air or in water. During the setting of the concrete the resistance in the dry increased slowly a t first, then more rapidly to 16,000 ohms and more, the rate depending upon the weather. Blocks lying in water increased in weight by absorption of water, while the resistance went quickly down in eight hours from 2200 ohms t o about zoo ohms, and remained a t that value; the concrete had been allowed to set properly for many days before being immersed in water. When alternating currents were used with wet cement, the drying effect (produced by the heating) raised the resistance. The results of the electrolytic corrosion tests on the whole agreed with previous tests; in some cases corrosion was observed with continuous currents of lower intensity than is sometimes assumed; occasionally efflorescences of hydroxides of aluminum and iron were noticed. The usual effect is, of course, that the iron is oxidized, swells and cracks the concrete, to which moisture thus gains access. With alternating current wet concrete prisms lying in water absorbed, a t first, currents up to 1.5 amperes, but the temperature rose in the course of days to 104O C , within the blocks (as measured by embedded thermometers), while the water temperature did not exceed 42 '. After 81 days these blocks were still found in good and strong condition, though the bare-iron electrodes, treated with the same alternating current, began to corrode. Particular interest attaches to the high-tension experiments. The respective prism was placed on an earthed plate, and another iron plate, joined to a transformer, was put on top of the prism. When currents of 11,000volts and 0 . 2 2 ampere were applied, jets of steam were seen to issue from the block, after two hours, and the jets soon turned into arcs up to 6 cm. in length; some of these arcs fused the concrete, which finally split. These blocks did not contain any iron. When another block containing a spiral core of iron wire (this wire not being earthed) was similarly exposed to ZOO,OOO volts, the discharge did not pass through the concrete, but a spark or arc would appear somewhere and strike through the air to the earthed plate. It is hence suggested that the lightning-conductors in ferro-concrete structures should be arranged without regard to the iron embedded in the concrete, which cannot well be joined t o the conductor network. Some experiments were finally made on the insulating power of concrete. For this purpose blocks with wire spirals embedded in them were again used. On the block rested a bell insulator, supplied by the Porzellanfabrik Hermsdorf, to which a conductor I cm. in thickness was attached, which was connected with a 60,000-volt transformer. The concrete prism stood on an earthed plate, and a voltmeter was inserted between the upper extremity of the wire spiral (which projected out of the concrete in this case) and the earth. The path from the conductor to the earth was thus: bell insulator, concrete, iron spiral, concrete, metal base, and earth, Under these conditions the iron spiral would acquire a potential against the earth which w-ould depend upon the capacity of the bell insulator and the condition and thickness of the concrete layer. The potential difference of the wire spiral rose to 300 volts. This potential might be dangerous to people touching the concrete, provided the current intensity were sufficient. But assuming transformer currents of 100,ooo volts a t 50 periods, the bell insulators would not allow more than 0.63 milliampere to pass, while currents of less than 20 milliamperes are not considered dangerous. From
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T H E J O U R N A L O F I N D U S T R I A L A N D ENGI,VEERIiVG C H E M I S T R Y
this point of view blocks or columns of ferro-concrete might be used in insulating stands for high-tension insulators. Whether it is advisable to use the iron embedded in the concrete for the purpose of earthing such stands is another question. There might be mechanical damage by perforation of the concrete, though there would hardly be any electrolytic corrosion with high-tension alternating currents. TEMPERATURE REGULATOR A new tank temperature regulator is now offered under the trade name The “Sarco” Regulator. I t is easily installed and can be arranged to regulate the temperature of water or any other liquid. The internal construction of the apparatus is clearly shown in the cut. The thermostatic element “ A ” is a tubular receptacle containing a heavy h y d r o c a r b o n oil into which is inserted a piece of corrugated copper tubing, the length of which is extended or reduced by turning the regulator head “ C.” From this thermostatic element a piece of fine copper tubing “ D ” passes t o the controller “G,” which also contains a piece of corrugated tubing capable of compression when a n increase of temperature causes the surrounding liquid in “ A ” t o expand. It will be observed, t h a t the thermostatic element “A,” the connecting copp’er tube “ D ” and the controller “ G ” form one hermetically closed chamber. When temperature increases in “ A ” the pressure increases and is transmitted t o “G,” causing a compression of the copper tube “ F , ” which forces out the piston “ I ” and tends to close the valve. Spiral springs “ E ” and “ J ” operating in the opposite direction tend t o keep the valve open. Regulators can be furnished for the following ranges of tCmperature: 86-212’ F., 140-212’ F. and 176-212’ F., and others by special arrangement. The same thermostatic principle has been applied also t o room temperature regulator and to a mixing valve which makes possible a continuous discharge of water a t a constant temperature. STEAM RAISING BY GAS COKE The Journal of Gas Lighting and Water Supply, 125 (1914), 424, publishes some data on steam raising by gas coke, based, on evaporation tests officially conducted, under the direction of the London Coke Committee, on boilers a t a n important municipal pumping-station near London. The boilers are the ordinary Cornish type, and the full normal evaporative capacity was maintained during the tests without alteration of the existing furnaces or draught conditions. Ordi-
T‘ol. 6 , No. 4
nary medium-sized gas coke was fired exclusively during the tests, a t intervals of 30 to 40 minutes. The competing fuel was smokeless Welsh coal, which was usually stoked a t intervals of about 20 minutes. The results obtained demonstrate the comparatively high efficiency of gas coke as a steam-raising fuel, and its adaptability to existing conditions. The feed-water test-meter had been previously checked, and was correctly calibrated within fine limits. The coke fuel was weighed in small lots immediately before firing. Intervals of 1 ~ / 2 hours were allowed in order to establish coke-fires prior to the commencement of the tests, which were twice repeated with similar results. The draught (natural) available was 0.125 inch a t the furnace doors. Duration of t e s t s . . . . . . . . . . . . . . . . . . . . . . . . 4 hours S t e a m pressure-Maximum. .............. 103.0 lbs. Minimum. . . . . . . . . . . . . . 101.0 “ Mean. . . . . . . . . . . . . . . . . 101 5 ‘< Feed temperature, average. . . . . . . . . . . . . 175’ F T o t a l coke f i r e d . , . , , , , . , , . , , , , , , , , , . . 1,680.0 Ibs. Average per square foot of grate per h o u r . . 12.7 ” T o t a l water evaporated. . . . . . . . . . . . . . . . 16,liO.O ‘’ Water evaporated per pound of coke, a c t u a l , 9 620 “ F a c t o r of evaporation. . . . . . . . . . . . . . . . . . . . 1.078 “ Water evaporated per pound of coke a s fired f r o m a n d a t 212’ F . . . . . . . . . . . . . . . . . . . 10,370 “
Commenting on these figures, the Journal says: “Though gas coke is now being used extensively on all types of boilers in London, the Committee’s experience is that the efficiency of this fuel for steam-raising purposes is little understood by engineers in charge of boiler plants; and it is hoped that the above authenticated test figures may prove useful in dissipating prejudice and in extending the use of gas coke fuel for industrial purposes.” ENGINEERING REPORT ON ARGENTINE PETROLEUM Some time ago the Argentine Government appointed an engineer, to supervise the borings on the State reserves of Comodoro Rivadavia. According to the Buenos Aires correspondent of the Berliner Tageblatt the engineer has now presented a first report on the subject. It characterizes the depth of a n average of 1770 feet a t which petroleum has been bored as favorabl’e, especially when it is considered t h a t many very productive and remunerative deposits in other countries have to be pumped up from a depth of from 4000-5600 f t . The productivity of roo tons daily a t first and of from 20 tons to 2 5 tons later of the individual bore holes a t Comodoro Rivadavia leads to the conclusion that there is a possibility of working for many years. The Roumanian sources lie a t a depth of 2600 f t . and yield only I O t o 15 tons daily. Nothing definite can yet be stated as t o the extent of the Argentine deposits. The geological investigations which have been undertaken seem t o prove that the petroleum layers are situated in a stratum about 5 miles long and a few miles wide, which extends toward the Atlantic coast. It is assumed that deposits of bitumen exist in association with the oil, as certain gases and chemical substances have been found in the petroleum which would be able t o yield important byproducts on rational exploitation. The report proceeds to remark that i t can not yet be stated whether the expectations which have been raised will be fulfilled or, possibly, surpassed, until it is seen whether the sources of petroleum first bored in south Argentina only represent, as usual, the first of several superimposed layers or not. * * * The report suggests that the work should not be proceeded with too hastily, and that private capital as far as possible should be kept a t a distance or be so controlled by the Government that the greatest profit is not allowed t o be extracted within the shortest possible time, as this practice in other places has resulted in the waste of up to 70 per cent of the possible production of oil.
