Aluminum Company of America

Other

Ronald E Miller

Charles E Eckert

C Edward Eckert

Diran Apelian

Jan H Van Linden

Eric D Arndt

Thomas R Hornack

John M Urbanic

Joseph R Herrick

John L Genna

Rajakkannu Mutharasan

Jeffrey B Moreland

John A Kaems

George E Lyness

Clarence J Cox

Michael Scherbak

A filter system for removing solid impurities from molten metal is described comprising a housing containing vertically disposed rigid coarse filter facing the incoming flow of molten metal and capable of removing solids having a particle size of at least 10 microns and a rigid fine filter mounted vertically behind the coarse filter and capable of removing solids having a particle size as small as 1 micron. The apparatus further includes a heater for maintaining the temperature of the molten metal and a sparger mounted adjacent the front face of one filter to provide an intermittent gas flow over the face of the filter to dislodge solids on the filter as filter cake. In a preferred embodiment, the rigid filters are nested cylinders, and the molten metal is directed to the center of the smaller coarse filter cylinder from which it then flows through the coarse filter outward to and through the fine filter cylinder and then from the fine filter out of the filter housing.

Multistage rigid media filter for molten metal and method of filtering

A system for in-line alloying of a molten metal stream comprises: means for controlling mass flow rate of the stream; means for adding alloying material to the stream at an adjustable rate; means for determining chemical composition of the stream downstream from the material adding means, preferably at timed intervals; and means for adjusting the rate at which alloying material is added to the stream based on mass flow rate and the extent to which the determined stream composition differs from a desired composition. A method for conducting in-line alloying and analysis of a continuous metal stream is also disclosed.

In-line sampling/alloying system and method

A method for adding alloying material to a molten metal media, such as molten aluminum, is disclosed. The method includes converting the alloying material into a spray of superheated alloy material and directing the spray into the molten metal media at a depth below the media's surface to enhance dissolution and dispersion of the alloying material in the molten media.

Introducing materials into molten media

A system for adding alloying material to molten metal media is disclosed. The system includes spark cup means, preferably cylindrically shaped, which is partially immersed in the molten media. The spark cup preferably has a lower open end which is exposed to a submerged surface of the molten media and an upper inlet, at least a portion of which is located above an exterior surface of the molten media. Means for supplying the spark cup means with an arc shielding gas through the inlet is provided as is means for feeding an elongated form of the alloying material through the spark cup inlet into the cup area or chamber of the spark cup. Also provided is means for establishing an electrical arc discharge between the submerged molten metal surface and the free end of the alloying element in the spark cup. The free end of the alloying element is converted into a spray of superheated alloy materials as it passes through the arc discharge. The shielding gas projects or directs the superheated spray of alloying material into the melt via the submerged surface in the open end of the spark cup. The spark cup is preferably configured to enhance such projection.

Alloying system

Process for adding material to molten media

Molten aluminum or other metals are purified by contacting with a fluorocarbon, such as CCl.sub.2 F.sub.2, in order to decrease the amount of impurity metal elements along with gas and inclusions therein preferably in the presence of an agitator to enhance efficiency. An oxidizer, such as oxygen, is employed to prevent the carbon in the fluorocarbon from forming carbide inclusions. Oxidizing the carbon to carbon monoxide is preferred in treating aluminum since the monoxide effectively removes the carbon from the system without oxidizing aluminum. Preferably, a fluorine acceptor is employed to temporarily combine with the fluorine in the fluorocarbon and prevent it from reacting with carbon such that the fluoride is still available to treat the molten metal. The gases employed to treat the molten metal can be passed over a bed of carbon immediately prior to introduction into the melt. The system operates with low skim generation and without providing a salt cover and is capable of substantially fume-free operation.

Metal treatment system

A method of removing skim from molten metal comprises providing a body of molten metal and passing a fluxing gas therethrough to carry skim to the surface of the metal. The skim on the surface is treated to substantially reduce the amount of molten metal contained therein and to provide the skim in a substantially powdery form. A portion of the treated skim in finely divided form is removed to a collector.

Skim removal

A method is provided for substantially completely removing volatilizable and combustible impurities from the surface of metallic scrap comprising the steps of continuously depositing surface contaminated scrap onto the surface of a stream of molten metal, directly propelling the floating scrap along the molten surface for a time sufficient for the heat from the molten metal to effectuate substantially complete removal of the contaminants from the scrap and forcibly submerging the remaining decontaminated scrap into the molten metal stream. A system is also provided for removing impurities from the surface of scrap comprising a trough of molten metal, means for moving the molten metal through the trough, means for continuously depositing contaminated scrap onto the molten metal surface, means for propelling the floating scrap through the trough and means for forcibly submerging the remaining floating scrap into the molten metal after the contaminants are substantially completely removed.

Growing community of inventors

Murrysville, PA, United States of America

Ronald E Miller