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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 .
matter has been removed, thus leaving a small though very important work for the filter t o accomplish. The filter chamber is filled with a series of horizontal corrugated plates and perforated retaining rings, between which are placed one or more thicknesses of
4
Oct., 1 9 1 1
is possible otherwise and continue t o deliver a product of the required fineness. Where it is desirable t o aerate the products to be handled, the separator can be made t o automatically aerate the liquids as they pass through it and thus do away entirely with the necessity of air pumps or other equipment and labor necessary for aerating purposes with other filtering processes. This machine is built b y the De Lava1 Separator Company, 165 Broadway, New York City. The manufacturers state t h a t with due care this clarifier and filter will last a lifetime. The average operator finds no trouble whatever in adjusting or cleaning any of the machine's parts and keeping it ever ready t o perform its work. The chief advantages claimed for this machine are as follows: The clarifier and filter will take any product to which it is adapted immediately after compounding and deliver continuously (except for occasional cleaning of the machine) a finished article ready for the market. I t thus greatly reduces the capital necessarily tied up in settling tanks with other methods. The manufacturer claims a n average saving of 90 per cent. in filter paper and cloths and their subsequent washing and cleaning over that required b y other processes, also a saving of liquid absorbed b y the
Fig. 2 .
filter material, paper, felt, cloth or whatever mal; be best adapted to the work in hand. The liquid is forced from compartment D upward into the compartment E , which is a narrow space between the periphery of the filtering chamber and the filtering disks. This allows a channel for the liquid to pass up, from which i t is delivered into the several compartments F, where it is forced through the filtering material G into compartment H. Here it is again forced t o the center and upwards through channel I to the discharge point J and into the large cover from which it flows into the receptacle awaiting it. The functions of the clarifying and filtering compartments supplement each other very thoroughly. The liquid is so thoroughly clarified by the disk system in the lower clarifying compartment t h a t i t leaves but a small amount of work for the filter to perform. Then, too, the filters being placed horizontally are substantially self-cleaning, for as the sediment or flock forms in any volume on the filters the centrifugal force throws it off and it is deposited at the outside or periphery of the compartments. Thus the filter material will do its work very much longer than
Fig. 3.
filter paper and that lost by evaporation or dripping with other methods, a saving of liquid, labor and the losses that sometimes occur from punctures in paper and a big saving in floor space.
AN AUTOMATIC PIPETTE. By
GEO.
E. BOLTZA N D
CHAS
J.
SCHOLLENBERGER
Received August 10, 1911.
Every analyst who makes a large number of determinations of the same character, each involving
Oct., 1 9 1 1
THE J O U R N A L OF I i V D l J S T R I i l L AND E N G I N E E R I N G C H E M I S T R Y .
the use of a constant volume of a solution as of a caustic alkali, knows the amount of time *ail’ trouble required for measuring out the reagent .used, and the generally unsatisfactory nature of such Cpparatus for this purpose, as t h a t provided with g1:lss stopcocks. Therefore, the following described butomatic pipette was designed for the rapid measur:ment of the alkali hydroxide and sulphide solution u-zd in the Kjeldahl method for nitrogen, b u t may bP adapted t o other uses as well. The body ( A ) of the pipette is made of a gection of wide glass tubing (the neck of a flask SerTreS well), provided a t the bottom with a rubber stc,,per perforated with two large holes; into each of. *’lese holes is fitted a short piece of glass tubing, one of’ which is
A 6
c
-- OS OEOLVI VoL rR RIPLTTE Y TUBE - SUPPLY T U B E -
D E-
SIPMOM TUQL S U W L Y eOTTLE
F-
DELIVERY TfP
C
‘ I L L G U L A T I M G TUBE
-
connected to a siphon tube ( D ) for filling, bent as shown in the drawing, the other t o a glass tip ( F ) for delivery, by suitable lengths (B) and (C) of rubber tubing. The top of the pipette is closed by a well fitting rubber stopper, carrying a single glass tube (G) of small diameter, which must be long enough t o extend well above the level of the liquid in the supply bottle (E) ; b y moving this tube in the stopper, the volume delivered by the pipette can be regulated. A piece of strong steel wire, shaped as shown in drawing D”, is soldered or preferably brazed securely to a heavy pinchcock of the common t y p e ; the completed article is shown in -4 and A’. This pinchcock is placed on the rubber tubes of the pipette so that tube X, for delivery, is normally compressed, and the pipette fills; on working the pinch-cock, 0 is closed, X for delivery opened, and the pipette is emptied. The apparatus is easily and cheaply con-
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structed and when properly made will deliver a volume of, say 5 0 cc., constant t o within one-half cc. The writers desire t o acknowledge their indebtedness to Mr. J . YV. Ames, chief of the Chemistry Department of this Station, for his kindness in giving this device a practical trial. O H I O .%GRICULTURAL E X P E R I M E N T S T A T I O N . WOOSTER
OHIO
_---_APPARATUS FOR RECEIVING AND MEASURING OIL OR NAPHTHA DISTALLED WITH STEAM. BY 0 H.
WURSTER
The naphtha content of a certain class of soaps and soap powders and the “oil” content of paraffine
d
