Abstract: A method of producing aluminum in an electrolytic cell comprising the steps of providing an anode in a cell, preferably a non-reactive anode, and also providing a cathode in the cell, the cathode comprised of a base material having low electrical conductivity reactive with molten aluminum to provide a highly electrically conductive layer on the base material. Electric current is passed from the anode to the cathode and alumina is reduced and aluminum is deposited at the cathode. The cathode base material is selected from boron carbide, and zirconium oxide.

Abstract: An improved Si—Cu—Mg—Al base alloy suitable for forming in the semi-solid condition into members such as vehicular members having improved properties.

Abstract: One or more aerators move below an area of an assembly of immersed filtering membranes to be aerated. The movement can take various forms including the sweep of a pendulum. Positions in the assembly of membranes may be alternately aerated for a period of time and then not aerated for a period of time.

Abstract: A method of producing aluminum in a low temperature electrolytic cell containing alumina dissolved in an electrolyte. The method comprises the steps of providing a molten electrolyte having alumina dissolved therein in an electrolytic cell containing the electrolyte. A non-consumable anode and cathode is disposed in the electrolyte, the anode comprised of Cu—Ni—Fe alloys containing 0.1 to 5 wt. % carbon and incidental elements and impurities. Electric current is passed from the anode, through the electrolyte to the cathode thereby depositing aluminum on the cathode, and molten aluminum is collected from the cathode.

Abstract: A container for molten metal which uses heat of solidification for heating the molten metal.

Abstract: An element of immersed, suction driven, filtering membranes has a plurality of hollow fiber membranes suspended between upper and lower headers. The lower header is movable between a first position in which the fibers are substantially elongated and second position in which the two headers are closer to each other by between 1 and 4% of the un-potted length of the membranes. The weight of the lower header is sufficient to keep the lower header in the first position in substantially quiescent water while allowing the lower header to rise to the second position in upwardly flowing water. Aerators are mounted generally below the elements and supply scouring bubbles to each element at a higher rate and then at a rate less than one half of the higher rate in repeated cycles. The cycles are preferably between 10 seconds and 60 seconds in duration. The lower header rises to the second position when bubbles are supplied at the higher rate and falls to the first position when bubbles are supplied at the lower rate.

Abstract: A method of heating molten aluminum in a container utilizing gas stirring means.

Abstract: A method of casting an aluminum base alloy to provide a cast product having improved hot crack resistance in the as-cast condition, the method comprising providing a melt of an aluminum base alloy comprised of 2.0 to less than 3.5 wt. % Zn, 2.5 to less than 4 wt. % Mg, a maximum of 2 wt. % total Fe and Mn in combination, max. 0.3 wt. % Si, max. 0.6 wt. % Cu, optionally up to 0.5 wt. % Cr, dissolved Ti in the range of about 0.005 to 0.1 wt. %, and an undissolved nucleating agent in the range of about 0.002 to 0.1 wt. % for grain refining, the balance comprised of aluminum, incidental elements and impurities. A nucleating agent selected from the group consisting of metal carbides, aluminides and borides is added to the melt to provide an undissolved nucleating agent therein, in the range of 0.002 to 0.1 wt. % for grain refining. The said alloy is solidified to provide a cast product having a grain size of less than 125 microns and free of hot cracks.

Abstract: A single tank submerged membrane bioreactor for treating feed water having unacceptable levels of ammonia or total nitrogen has both a membrane scouring bubble supply and an oxygenating bubble supply. The membrane scouring bubble supply continuously provides large scouring bubbles to clean the membranes. Permeate is continuously withdrawn from the membranes at a high rate but the large scouring bubbles do not transfer sufficient oxygen to the mixed liquor to create aerobic conditions in the reactor. The oxygenating bubble supply is operated to provide small bubbles of air or oxygen that intermittently produce aerobic conditions in a significant part of the mixed liquor. Alternating aerobic and anoxic conditions occur in a significant portion of the tank suitable for nitrification and denitrification.

Abstract: A method of preparing carbonaceous blocks or bodies for use in a cathode in an electrolytic cell for producing aluminum wherein the cell contains an electrolyte and has molten aluminum contacting the cathode, the cathode having improved wettability with molten aluminum. The method comprises the steps of providing a carbonaceous block and a boron oxide containing melt. The carbonaceous block is immersed in the melt and pressure is applied to the melt to impregnate the melt into pores in the block. Thereafter, the carbonaceous block is withdrawn from the melt, the block having boron oxide containing melt intruded into pores therein, the boron oxide capable of reacting with a source of titanium or zirconium or like metal to form titanium or zirconium diboride during heatup or operation of said cell.

Abstract: A container for molten metal which uses heat of solidification for heating the molten metal and method of heating body of molten aluminum.

Abstract: A method and apparatus of purifying feedwater to remove impurities including suspended solids therefrom, the method suitable for using in-line water pressure to permeate water through hollow fiber membranes and to backflush the membranes to remove solids collected or deposited thereon.

Abstract: A method of dispensing or pouring molten metal, e.g., aluminum, from a container or vessel, the flow rate controlled to minimize splashing of the molten aluminum exiting the container, the method comprising the steps of providing a container for containing molten metal, the container having an outlet for dispensing molten metal therefrom and providing a body of molten aluminum in the container, the body having a top surface. A pressure lower than atmospheric pressure is maintained on the surface of the body in the container vessel for purposes of controlling the flow of molten metal through said outlet. Molten metal is dispensed through the outlet by increasing the pressure maintained in the container towards atmospheric pressure.

Abstract: A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte, the method comprising the steps of providing a molten salt electrolyte at a temperature of less than 900° C. having alumina dissolved therein in an electrolytic cell having a liner for containing the electrolyte, the liner having a bottom and walls extending upwardly from said bottom. A plurality of non-consumable anodes and cathodes are disposed in a vertical direction in the electrolyte, the cathodes having a plate configuration and the anodes having a flat configuration to compliment the cathodes. The anodes contain apertures therethrough to permit flow of electrolyte through the apertures to provide alumina-enriched electrolyte between the anodes and the cathodes. Electrical current is passed through the anodes and through the electrolyte to the cathodes, depositing aluminum at the cathodes and producing gas at the anodes.

Abstract: A method for filtering molten aluminum containing suspended particles using an improved filtration media, the method comprising the steps of providing a source of molten aluminum and providing media having a coating thereon, the coating having a softening point at molten aluminum temperatures to provide adhesive properties and bonding of suspended particles in the molten aluminum thereto. The filtration media is contacted with molten aluminum and suspended particles are adhesively bonded thereto to provide molten aluminum having suspended particles removed therefrom.

Abstract: A shaft for use with molten aluminum using an impeller mounted on the shaft comprising a protective refractory sleeve resistant to attack by molten aluminum, the protective sleeve employing a reinforcing media and mounted on the shaft to extend above and below the molten aluminum surface when the shaft is in use.

Abstract: A method of treating an electrolyte for use in the electrolytic reduction of alumina to aluminum employing an anode and a cathode, the alumina dissolved in the electrolyte, the treating improving wetting of the cathode with molten aluminum during electrolysis. The method comprises the steps of providing a molten electrolyte comprised of ALF3 and at least one salt selected from the group consisting of NaF, KF and LiF, and treating the electrolyte by providing therein 0.004 to 0.2 wt. % of a transition metal or transition metal compound for improved wettability of the cathode with molten aluminum during subsequent electrolysis to reduce alumina to aluminum.

Abstract: An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises a molten electrolyte having the following ingredients: (a) AlF3 and at least one salt selected from the group consisting of NaF, KF, and LiF; and (b) about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound may be, for example, a fluoride, oxide, or carbonate. The metal can be nickel, iron, copper, cobalt, or molybdenum. The bath can be employed in a combination that includes a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the bath of the present invention during electrolytic reduction of alumina to aluminum can improve the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode.

Abstract: The invention comprises an electric heating assembly having improved heat transfer, the heater comprised of a receptacle for containing amalgam heat transfer media. An amalgam heat transfer media is provided in the receptacle for purposes of heat transfer. An electric heating element is located in the amalgam. When the amalgam reaches a solidified condition, a receptacle or mold is not required for the electric heating assembly.

Abstract: A method for processing alumina-bearing ores such as bauxite to recover iron, aluminum, silicon and titanium metal values therefrom the method comprising the steps of adding the alumina-bearing ores to a digester containing an acid to provide a mixture of acid and alumina-bearing ores and heating the mixture to dissolve soluble compounds of at least one of iron, aluminum, silicon and titanium to provide a digest containing dissolved salts of the soluble compounds and to provide a gas component. Thereafter, the digest is treated with water to dissolve water soluble salts therein to provide a slurry comprised of a liquid containing water and the dissolved soluble salts and a solid component comprised of silica. The solid component is separated from the liquid and the pH of the liquid is adjusted to form an aluminate and an iron-containing precipitate.