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Vertical tube apparatus

There are several different devices for determination of dust explosion characteristics. All devices include a vessel which may be op>en or closed, an ignition source which may be an electrical spark or electrically heated wire coil and a supply of air for dispersion of the dust. The simplest apparatus is known as the vertical tube apparatus and is shown schematically in Figure 15.4. The sample dust is placed in the dispersion cup. Delivery of dispersion air to the cup is via a solenoid valve. Ignition may be either by electrical spark across electrodes or by heated coil. The vertical tube apparatus is used for the classification test and for determination of minimum dust concentration for explosion, minimum energy for ignition and in a modified form for minimum oxygen for combustion. [Pg.380]

Figure 15.4 Vertical tube apparatus for determination of dust explosion characteristics. Figure 15.4 Vertical tube apparatus for determination of dust explosion characteristics.
The minimum dust concentration for explosion is measured in the vertical tube apparatus and is used to give an indication of the quantities of air to be used in extraction systems for combustible dusts. Since dust concentrations can vary widely with time and location in a plant it is not considered wise to use concentration control as the sole method of protection against dust explosion. [Pg.382]

Fig. II, 41, 4 is an apparatus for the continuous steam distillation of a liquid which is heavier than water. The aqueous mixture is placed in the flask A of relatively large capacity the receiver B consists of a distilling flask (provided with a stopcock at the lower end), the capacity of which is less than the volume of the liquid in A, and is placed several inches higher than the opening in the wide vertical tube C. The lower end of the funnel D must-be below the side arm of the receiver in order to prevent bubbles of the heavy liquid from collecting on the surface of the steam distillate and being carried back to the flask A. The rubber tube E for the returning aqueous liquor must at some point be lower than the entrance to the tube C so that a trap of liquid will be formed and prevent the vapours from A entering the side tube. Fig. II, 41, 4 is an apparatus for the continuous steam distillation of a liquid which is heavier than water. The aqueous mixture is placed in the flask A of relatively large capacity the receiver B consists of a distilling flask (provided with a stopcock at the lower end), the capacity of which is less than the volume of the liquid in A, and is placed several inches higher than the opening in the wide vertical tube C. The lower end of the funnel D must-be below the side arm of the receiver in order to prevent bubbles of the heavy liquid from collecting on the surface of the steam distillate and being carried back to the flask A. The rubber tube E for the returning aqueous liquor must at some point be lower than the entrance to the tube C so that a trap of liquid will be formed and prevent the vapours from A entering the side tube.
Based on the general scenario provided above, the analytical method to determine transference or transport numbers has been devised and is carried out in an apparatus which can essentially be regarded as an improvement over the Hittorf apparatus. This consists of two vertical tubes connected together with a U-tube in the middle all three tubes are provided with stop-cocks at the bottom. The U-tube is also provided with stop-cocks at the top by closing these, the solutions in the cathode and anode limbs can be isolated. The silver anode is sealed in a glass tube as shown, and the cathode is a piece of freshly silvered silver foil. The apparatus is filled up with a standard solution of silver nitrate and a steady current of about 0.01 ampere is passed for 2-3 hours. In order to avoid the occurrence of too large a change in concentration it is necessary to pass the current only for a short duration. The... [Pg.618]

The apparatus used to determine the transport number by the moving boundary method is shown in Figure 6.4. It consists of a long vertical tube of uniform cross-section which is fitted with two electrodes at the two ends. Let the electrolyte, the transport number of whose... [Pg.619]

Fill the gel particles together with the surrounding buffer into the tube. The tube is inserted into the vertical electrophoresis apparatus (dialysis membrane down to anode), electrode buffer is poured, and electroelution is started with 10 mA per tube for 3-8 h, depending on tbe molar mass of the protein. [Pg.66]

QA 54, 7149(1960) (Dust explns in factories new vertical tube test apparatus)... [Pg.255]

The thermal diffusion method of isotope separation has broad application to liquid-phase as well as gaseous-phase separations. The apparatus widely used for this purpose consists of a vertical tube provided with an electrically heated central wire. The gaseous or liquid mixture containing the isotopes to be separated is placed in the tube, and heated by means of the wire. In such an apparatus two effects act to separate the isotopes. Thermal diffusion tends to concentrate the heavier isotopes in the cooler outer portions of the system, while the portions near the hot wire are enriched in die lighter isotopes. At the same time, thermal convection causes the hotter fluid near the hot wire to rise, while the cooler fluid in the outer portions of the system tends to fell. The overall result of these two effects causes die heavier isotopes to collect at the bottom of the tube and the lighter at the lop, whereby both fractions may be withdrawn... [Pg.1649]

Continuous Steam Distillation.—The apparatus (Fig. 16) is very convenient when this process has to be carried on for some time. The substance to be steam distilled is placed in the round-bottomed flask A along with water if none is present. To the flask is attached through a cork a tube delivering to a vertical tube B, and with a small side tube C. A... [Pg.25]

Brown, K. C. and Essenhigh, R. H., Dust Explosions in Factories A New Vertical Tube Test Apparatus. Safety in Mines Research Establishment Research Report, No 165, Ministry of Power, Sheffield, England (April 1959). [Pg.140]

The chlorination of ferrosilicon is also possible in a horizontal apparatus shown in Fig. 22. This changes the construction of the whole condensation system, which is basically one unit with the chlorinator. Horizontal furnace 1 is a 600 mm tube from one side this tube is covered with a water-cooled door, and from the other side it joins the first condensation tube 3. The chlorinator has a filling device 2, which is a small vertical tube with a gate on top, used for loading ferrosilicon. The furnace, the vertical tube and the chlorine-feeding choke have cooling jackets. [Pg.100]

The circulation and bubble tubes are vertical apparatuses with vapour jackets. The reactors are vertical cylindrical apparatuses with spherical welded bottoms and removable lids (with cylindrical baskets" with cationite KU-23 or askanite. The reactors are fashioned with capacitance moisture indicators. To moisturise cationite or ascanite, the apparatus is filled with live steam. The separators are vertical cylindrical apparatuses with conical bottoms and removable spherical lids. The reactors and separators operate under 0.02 MPa. [Pg.183]

Procedure Set up the apparatus as shown in Fig. 10. Clamp the wash bottle in an inverted position. Attach a 2-foot piece of rubber tube to the mouth piece of the wash bottle. Slip a pinch cock over the tube, and insert a small funnel in the open end. Raise the funnel to the position shown by the dotted lines in Fig. 10. Pour water through the funnel, and fill the wash bottle nearly to the top of the vertical tube. Close the pinch cock, and replace the funnel with the capillary tip from the wash bottle. Connect the other tube of the wash bottle to the Pyrex test tube by means of an elbow tube and rubber connection. Open the pinch cock and allow water to run out of the wash bottle into the beaker. If the apparatus is tight the flow of water will stop completely after a moment. Close the pinch cock, remove the Pyrex test tube, dry it, and weigh it accurately. Place in it... [Pg.26]

The reliability of this value of the faraday has been confirmed by measurements with the iodine coulometer designed by Washburn and Bates, and employed by Bates and Vinal. The apparatus is shown in Fig. 4 it consists of two vertical tubes, containing the anode (A) and cathode (C) of platinum-iridium foil, joined by a V-shaped portion. [Pg.19]

The method of balancing columns with two liquids, one of known density, contained in a U-tube, is suitable only for immiscible liquids, but the modification used in Harems apparatus can be used for miscible liquids with small vapour pressures. The two liquids are drawn up into vertical tubes joined at the top and communicating there with a tube through which the air pressure can be reduced. The heights of the two columns above the levels in the vessels containing the liquids are inversely as the densities,. hijh2=Q2lQi-... [Pg.12]


See other pages where Vertical tube apparatus is mentioned: [Pg.357]    [Pg.357]    [Pg.70]    [Pg.323]    [Pg.149]    [Pg.869]    [Pg.347]    [Pg.889]    [Pg.1092]    [Pg.75]    [Pg.582]    [Pg.15]    [Pg.218]    [Pg.8]    [Pg.149]    [Pg.869]    [Pg.44]    [Pg.145]    [Pg.496]    [Pg.347]    [Pg.79]    [Pg.96]    [Pg.2342]    [Pg.203]    [Pg.36]    [Pg.495]    [Pg.96]    [Pg.155]    [Pg.1]    [Pg.137]    [Pg.712]    [Pg.113]    [Pg.282]    [Pg.11]    [Pg.78]   
See also in sourсe #XX -- [ Pg.380 , Pg.381 ]




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Vertical tubes

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