Estimating on the Cost of Power Plants. - Industrial & Engineering

May 1, 2002 - Estimating on the Cost of Power Plants. Ind. Eng. Chem. , 1913, 5 (6), pp 515–516. DOI: 10.1021/ie50054a045. Publication Date: June 19...
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June, 1913

T H E JOCR.\73L

OF I-1-D L-.STRIz4L A S D E S G I S E E R I - V G C H E M I S T R Y

for a period of three to four days. SV.J . Luxmoore, of London, now finds that artificial leather may be manufactured from this product, which is marketed under the name “Syrolit,” by incorporating with it rubber, gutta percha, etc. The composition is rolled through pattern rollers in order to imitate the surface of leather. RUBBER I N HAWAII *kccording to Rubber World, 7 , No. 1j8, 8 , rubber is steadily becoming a n important Hawaiian product. On the island of Maui many trees have been planted and these are being tapped in large numbers. Steady efforts are being made to improve the methods of preparation in order to increase the marketable value: 3j,ooo trees were tapped during 1912, and altogether some 8,000 pounds of rubber were produced, most of which was exported. For 1913, a n output of 20,000 pounds is anticipated. Attention has been directed to a n indigenous rubber tree (Euphorbia lorijolia) which grows in several localities; one place in particular on the Island of Hawaii has 6,000 trees averaging i j trees to the acre, whose product is 14-1 j per cent of rubber and 60 per cent of resin (chicle). I t is reported that the latex contains 42 per cent of solid material and that one man can collect 16-30 pounds of crude product per day. Die Chemische Industrie, 36, NO. 7, 205, also refers to the cultivation of rubber in Hawaii. According to this journal, the available statistics are as follows: Company

Founded

Nahiku Rubber Co. . . . . . . . . . . . Hawaii-American C o . . . . . . . . . . . . Koolan Rubber C o . . . . . . . . . . . . S a h i k u Sugar Co.. . . . . . . . . . . . . Pacific Development Co . . . . . . .

1905 1905 1906 1906 1907

Capital $150,000 S 50,000 S 30,000

....

B

80,000

Planted territory in acres 480 245 2i5 250 250

-~

THE USE O F “HUMIN” I N THE PURIFICATION OF SUGAR FACTORY WASTE WATERS I n the beet sugar factory the waste waters from the washers, the diffusion battery, and the chip presses are usually purified by simply liming and settling. This has been said to be unsatisfactory, owing to the occurrence of putrefaction, hydrogen sulfide being evolved and the water darkened. I n 1911, Thein (Deut. Zuckerind., 36, 286) stated that excellent results had been obtained by the use of the Hoyermann-SVellensiek process, which consists in the use of a preparation termed “Humin,” obtained by treating brown coal rich in humic matter with sodium hydroxide. H e reported that when the “Humin” was mixed with warm condenser water, using a sufficient volume of this to impart a light brown color to the waste water, and then liming to weak alkalinity, a voluminous precipitate mas obtained, which rapidly subsided, leaving the water clear and practically free from bacteria. Andrlik and Stanek [ Z . Zuckerind. Biihm., 37, 2 8 2 (1913)] conducted a n elaborate investigation of the process of Hoyermann and Wellensiek, and have been led to conclude that the employment of “Humin” and lime does not effect any greater purification of sugar factory waste waters than is accomplished by the use of lime alone. “CELLOPHANE” Muller (Chem. Ztg., 37, No. 4 0 , 404) regards “Cellophane” as a “Viscose” product of the highest technical importance. It is prepared by precipitating a xanthogenate solution with ammonium chloride. Colorless films about 0 . 0 2 mm. in thickness may be obtained from “Viscose” solutions, and these are marketed in rolls, uniform in thickness and width; the weight of a square meter varies from I j g. upwards to 1600 g., accdrding to requirements. I n preparing the heavier thicknesses, two or more layers are worked up together. The elasticity of “Cellophane” is said to be remarkable; the films are also impermeable

515

to water, oils and gases, and are non--inflammable and nonexplosive. Paper coated with “Cellophane” is claimed to possess more technical advantages than lead, tin, zinc and aluminum (“Alolit”) foils, mainly owing to its lightness, non-oxidizability and cleanness; in addition, hluller states that it is gas-tight. “Cellophane” is insoluble in 1%-aterand alcohol, and’it may be treated with boiling water without indications of decomposition. I t is not altered when heated to about 120’ C. Like “Guadafil” (see Baroni, Giorn. Farm. Chim., 60, 239), “Cellophane” is particularly important because of the fact that the films can be made into any desired shape by softening in, say, mater and drying after molding to the proper form. SAFETY FUSES AND DETONATORS The Chemical Trade Journal, 5 2 , 417, reports that important extensions are being made to the Regent Factory a t Linlithgom, belonging to Nobel’s Explosive Company. This factory is devoted entirely to the manufacture of safety fuses for use in connection with the various high explosives which are manufactured a t Ardeer in considerable quantities-dynamite, blasting gelatine, gelignite, samsonite, carbonite, monobel powder, lyddite, cordite, ballistite, guncotton, etc. At Westquarter, Polmont Station, the company has a factory for the manufacture of detonators. The safety fuse consists of jute yarn spun around a central core of black gunpowder, and waterproofed by a coating of pitch and gutta-percha. 4 thin red strand runs through the powdered core. The fuse varies in diameter from to of a n inch. The core is of fine-grained gunpowder, which, on ignition, burns evenly a t a sloiv rate, conveying fire to the charge or detonator in the case of high explosives. I t is said that much care has to be exercised in the formation of this core to prevent gaps and also to ensure evenness of the time of burning. Generally, ten jute yarns are spun so as to enclose the powder as it flows down from the nozzle of the hopper, and a number of threads are in turn spun around these in the opposite direction. Coatings of specially prepared pitch compounds or gutta-percha are subsequently applied to the semi-manufactured fuse or “rod” thus formed, with a further layer of threads or tape. The surface coating is a varnish of pitch, china clay, or some colored compound. Samples of the finished fuse are tested to make certain that the rate of burning is correct. I n this connection, X-rays have been found to be exceedingly satisfactory, immediately detecting irregularities in the powder core. As regards the speed of burning, the rate is generally about 90 seconds per yard; but for South Africa it is slower-about IOO seconds per yard. Safety fuses are divided into two classesthose for use in dry ground, and those which must be waterproofed, either for submarine work, for placing in wet bore-holes, or for open work in rainy seasons. ,4t the Westquarter Factory detonators are turned out in extraordinary quantities annually. Fulminate of mercury in a copper tube is the basis of the detonator, which is fired by means of high- or low-tension fuse, or a safety fuse. Made in six sizes, the charge of fulminate for the detonators ranges from 8.3 grains in detonator No. 3 to 30.9 grains in No. 8. ESTIMATING ON THE COST OF POWER PLANTS F. I\‘. Gay ( J . ‘Il’orcester Polytechnic Inst., March, 19;3) gives a n important method of checking estimates on the cost of construction of power plants, in which the greatest chances of error are confined to the minor parts of the installation. Gay has compiled data and prepared diagrams covering power plants from 2,000 to 40,000 kw. in capacity. His experience shows that engines and foundations constitute from 33.6 per cent to 61 per cent of the total equipment cost--an average of j o per cent; boilers, settings and foundations, from 1 j . 2 j per cent to 31.5 per cent-average about z j per cent; piping, complete, irom i per cent to 1 7 per cent-averages about 1 1 per cent; condensers,

T H E J O U R N A L OF I h ‘ D U S T R I A L A N D EA’GIAIEERII\~G C H E - V I S T R Y complete, with foundations and auxiliaries, I O per cent to I j per cent-average about I I per cent; circulating-water system, 4.j to 8 per cent-averages about6.j per cent. Thisis a minimum of 7 2 . 3 j per cent of all apparatus items, leaving the remainder, 27.65 per cent, to be divided among a t least eleven groups, including “miscellaneous.” Therefore, the greater part of the allowable time should be spent on these five groups. Gay finds it possible to estimate as close as 3 per cent on boilers, installed; on engines, installed, as close as j per cent; on engine foundations, as close as I O per cent; on circulating-water systems, as close as 15 per cent; on piping systems, as close as 20 per cent; and on condensers, auxiliaries and foundations, as dose as 3 per cent. Buildings for this apparatus vary from 6 per cent to 16 per cent., a n average, say, of I O per cent.

THE “HYDRO-CATOR” Alnew type of gauge for indicating liquid levels, termed the “Hydro-Cator,” is being- manufactured by a Detroit, Mich., company. I t is claimed that by using this gauge the height of all kinds of liquids in tanks and reservoirs may be accurately indicated. The instrument is described as a fluid gauge h a v i n g n o mechanical parts; it is actuated by the pressure or weight of the liquid contained in COMPRESSOR^ the tank upon a n attached compressor, which is connected by capillary tubing, containing air only, with a gauge calibrated in feet and inches. The “Hydro-Cator” may be placed either above or below the tank or reservoir. When located below the tank, as is shown in the figure, the capillary tube is run directly above the tank one foot or more before leading down to the instrument. The compressor may be connected to the outside of the tank or lowered down on the inside; in either case its base must be level with the inside bottom of the vessel. - 7 -

THE RIDEAL-EVANS CHLOROMETER The Rideal-Evans electric apparatus for the automatic indication of chlorine, ozone and other oxidizing sterilizing agents in solution is diagrammatically illustrated herewith. I t consists of a copper tube, C, 3.5 cm. in length and 4 mm. internal diameter. Within this, running axially through it, is a platinum rod, P (diam. I mm.), which is insulated a t the two ends from the copper tube by two ebonite caps, E,E’. Liquid is allowed to enter the instrument by the side tube BA and to leave it through A’B’; taps are provided at B,B’ to regulate the flow through the instrument, and are joined by insulated metal tubes, R,R’, to the center piece. The taps are fitted a t B,B‘ with adapters to screw into standard-thread l/,-inch metal tubing connected to the water main (or reservoir) and the waste pipe, respectively. By means of a terminal, T’, on the copper tube and a terminal, T, (connected to the platinum rod, through a plug switch, K), wires connect the instrument to a special current-measurer, which may be kept in any convenient position. The current-measurer is graduated according to the use to which the instrument is to be p u t ; for the usual purposes of water treatment it has been found convenient to graduate the scale so that one division represents one part of available chlorine per ten million. The

V O ~j, . NO. 6.

quantity of water needed for the apparatus is very small; even if it is always kept running though the apparatus, 2 to Isgallons per hour suffice for its efficient working. The form of instrument of the above sensitiveness will read up to strengths of approximately j parts of available chlorine per million, but the manufacturers state that special forms of the instruments can b e supplied to measure up to much higher concentrations of chlorine.

P-Platinum Rod. E E’-Ebonite Caps. 7 T-Terminais. R R-Insulated Metal

Tuben.

B B-Taps. K-Plug Swtch. AX-Entrance and Exit to Centre-piece.

rn Insulator.

I mtm hletal.

For public water supplies, the instrument may be placed so as to show the quantity of chlorine in a town water-supply as it leaves the waterworks. For sewage effluents, when the chlorometer is placed a t the point of discharge of theeffluent, it will indicate whether the desirable slight excess of sterilizer is present or not. Water to be used for textile finishing or in laundries is tested just as it enters the tanks. If, however, the chlorometer is to be employed in connection with swimming tanks, it should be attached a t the point of efflux. The instrument is attached on any convenient wall by means of four screws passing through the brass plate. The water t o be tested is conveyed by a small pipe which is connected to the apparatus a t B. The overflow escaping a t B‘ may be discharged down a waste or returned to the original supply. The rate of flow indicated is obtained by the adjustment of the tap B, the tap B’ being fully open. When adjustment is completed, the position of the tap B is allowed to remain stationary, and the water is turned on and off by means of the other tap B’, which is always kept closed or fully open. The terminals T and T’ are now joined to the current measurer by means of wire, the terminal T being connected with the positive pole. After setting up, water is allowed to flow through the instrument continuously for about 24 hours. Then the tap B’ is turned off and is only opened when i t is desired to make a reading. To take a measurement of chlorine in a water sample, the plug K is put into position, the tap B’ is opened, and when the dial pointer has arrived a t a position of equilibrium, the reading on the scale is noted. The action of the chlorometer is based solely upon depolarization and does not depend in any way upon the measurement of the conductivity of the liquid.

THE EFFIClENCY OF CONDENSER AIR PUMPS I n recent years, jet air pumps and rotary air pumps have been introduced for condenser service. The advantages of these types of pumps are as follows: they are simple, practically np attendance is required, and repairs may be easily made The introduction was facilitated by the shortcomings of the types of reciprocating air pumps in use until lately. These shortcomings consisted in complications such as mechanically operated valves, with the necessary valve gearing, large clea ance and flash ports, the necessity for close adjustment on account of the small width of the flash ports, their sensitiveness for entrained water and the fact that at high vacuum the heat of compression warps the mechanically operated valves, and thereby makes further increase of vacuum impossible. Frequently, these