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
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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
pumps were driven by steam cylinders with complicated Corliss valve gear. Coupled with these features was the general lack of knowledge of the volumetric efficiency of such pumps. In contradistinction to the ease with which tests can be run on jet and whirling air pumps, tests on reciprocating pumps require more expensive installation and equipment. According to the litdustrial H'orld, 47, No. 16,a new reciprocating pump has been placed on the market by a Pittsburgh. firm. This air pump, which is illustrated above, has no mechanically operated valves on the air cylinder, but has instead automatic valves of the multi-ported plate type. There are no flash ports and no large clearance spaces due to such flash ports. It is claimed that the valves require no attention and no oiling: they are said to open and close independent of any adjustment. The New Mesta Reciprocating Pump was tested for reliability and economy by W . Trinks. His results seem to show that the reciprocating air pump should be used wherever sufficient amount of exhaust steam for feed water heating is available from other sources. ___ A NEW GAS SCRUBBER W. R. Heslewood, of Berkeley, Cal., has devised a n apparatus for scrubbing flue gases, wherein the scrubbing is effected by water traversing a closed cycle, impelled by a centrifugal pump. The centrifugal pump delivers the water through a nozzle into
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a gas case composed of two reducers, bolted together a t their large ends and making up the suction line. The water proceeds from the second reducer into a n expanding nozzle, from which it is delivered into a tank through a perforated pipe. The centrifugal pump then draws its feed from the same tank. There is suction produced in the gas case by the jet of water, with the result that the flue gases are thereby drawn in, scrubbed and discharged through the holes in the exit pipe. While the
apparatus may be useful for scrubbing out. soluble liquids, solids, or gases, it should be determined whether any large amounts of insoluble flue dust would clog the pump and exit holes.
SCIENTIFIC SOCETIES PRELIMINARY REPORT FOR THE COMMITTEE ON COAL ANALYSIS OF T H E AMERICAN SOCIETY FOR TESTING MATERIALS AND T H E AMERICAN CHEMICAL SOCIETY By
I\'. A .
h-OYES
INTRODUCTION
Sometime ago committees were appointed by the American Society for Testing Materials and the American Chemical Society for the purpose of revising the standard methods of coal analysis. During the fall of 1911 the two committees were
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organized as a joint committee consisting of the following members: W. A. Noyes, Chairman, Perry Barker, H. C. Dickinson, A. F. Fieldner, Frank Haas, W. F. Hillebrand, S. W. Parr, S. S. Voorhees, A. H. White. At the Washington meeting of the American Chemical Society in December, 1911,this committee met and after a careful discussion of the problems to be considered appointed the following sub-committees: I . Preparation of samples, including loss of moisture in
