Abstract: A process to remove SO.sub.2 from mixtures by contacting SO.sub.2 -containing mixtures with a regenerable iron-bearing sorbent such as paint rock under reaction conditions to produce iron sulfide and an effluent containing reduced amounts of SO.sub.2.

Abstract: A pressure actuated sealing system for a travelling grate comprising at least one horizontally elongated rigid seal plate pivotally mounted below said travelling grate in sealing relationship with said travelling grate and with windbox means mounted below said travelling grate, said travelling grate including a plurality of pallets each with seal plate engaging means and cavity means provided on the underside thereof, said seal plate being pivotable in the direction of movement of said travelling grate by engagement with said seal plate engaging means, said seal plate being pivotable in the direction opposite the direction of movement of said travelling grate by the pressure differential across said seal plate formed by the pressure of the gases within said wind box means on one side of said seal plate and the ambient pressure on the other side of said seal plate, said cavity means being adapted for permitting unobstructed pivotal movement of said seal plate in said opposite direction.

Abstract: A mill liner for a dry autogenous mill includes low profile end liner elements at the ends of the mill incorporating radial ribs with proper height to provide significantly improved mill performance without sacrificing the grinding efficiency. Shell liner elements are also provided with lifter bars as an integral part thereof to simplify maintenance work as well as reduce scrap losses. For the larger size mills, the shell liners are preferably made of a three piece design, a middle section and two identical end sections, thus permitting the middle section which bears most of the wear to be replaced without having to replace the two end sections.

Abstract: A method for recovering nickel from a waste material containing nickel and small amounts of iron or aluminum or a mixture thereof comprising the steps of:(a) removing the organic impurities from the waste material;(b) leaching the material with an acid after removal of organic impurities to provide an acid solution;(c) precipitating said iron and aluminum from the acid solution; and(d) recovering nickel from the acid solution.

Abstract: A method of recovering copper from ores containing copper as atacamite/paratacamite by froth flotation is described which comprises utilizing as a collecting or flotation agent, a combination of two chelating agents having the formulaR--C(OH).dbd.N--OR.sup.1andR.sup.2 OCSSXwherein R is an aliphatic or aromatic group containing from 5 to 10 carbon atoms,R.sup.1 is hydrogen or an alkali metal,R.sup.2 is an alkyl group containing up to 10 carbon atoms, andX is an alkali metal.The method of the invention is useful in treating copper ores containing very small percentages by weight of copper.

Abstract: A mill liner for a dry autogenous mill includes low profile end liner elements at the ends of the mill incorporating radial ribs with proper height to provide significantly improved mill performance without sacrificing the grinding efficiency. Shell liner elements are also provided with lifter bars as an integral part thereof to simplify maintenance work as well as reduce scrap losses. For the larger size mills, the shell liners are preferably made of a three piece design, a middle section and two identical end sections, thus permitting the middle section which bears most of the wear to be replaced without having to replace the two end sections.

Abstract: Disclosed is a process for refining a magnesium and nickel containing ore, comprising the steps of grinding the ore; preparing a slurry of the ground ore in sulfuric acid containing less than ten percent of water; adding water to the acid-ore slurry in an amount which is effective to initiate a sulfation reaction; allowing the sulfation reaction to continue, utilizing the heat of the sulfation reaction to heat the acid-ore slurry, whereby water-soluble metal sulfates and insoluble residue are formed; leaching the sulfation product with water to extract the water-soluble metal sulfates in solution; separating the metal sulfates solution from the insoluble residue; precipitating from the solution metals other than Mg as hydroxides; separating the solution from the metal hydroxide precipitate; concentrating the solution sufficiently to precipitate CaSO.sub.4 ; separating the concentrated solution from the precipitate; recovering dehydrated MgSO.sub.

Abstract: A method for extracting chloride ions from copper-hydroxy-chloride containing copper oxide ore comprising the steps of(a) contacting said ore with an aqueous solution of the basic salt of a Group I-A or Group II-A metal in a leaching stage to extract chloride ions from said ore and dissolve said chloride ions in said solution;(b) removing part of said solution from the mixture of ore and solution as a bleed stream for chloride disposal; and(c) separating said ore from the remainder of said solution.

Abstract: This application is directed to the use of ferrous sulfate for absorption of sulfur from gases containing the same. The invention is predicated on the reaction of the sulfur oxides with ferrous sulfate in the presence of oxygen to form principally ferric sulfate.

Abstract: A method of recovering copper from ores containing copper as atacamite/paratacamite by froth flotation is described which comprises utilizing as a promoter collector compounds having the formulaRC(OH).dbd.N--O.sup..crclbar. H.sub.2 N.sup..sym. R.sup.1 R.sup.2whereinR is an aliphatic group containing from about five to ten carbon atoms or an aromatic group containing from six to about ten carbon atoms, andR.sup.1 and R.sup.2 are each independently alkyl groups containing from one to five carbon atoms.The method of the invention is useful in treating copper ores containing very small percentages by weight of copper.

Abstract: A method for removing sulfur and arsenic from cobaltiferous ores and recovering an enriched cobalt product is described. The procedure involves the steps of(a) oxidizing said ore at a temperature of at least about 700.degree. C. to reduce the sulfur content of the ore to the desired level,(b) heating said oxidized ore with a reducing agent at a temperature of at least about 700.degree. C. to remove arsenic from the ore, and(c) recovering an enriched cobalt containing solid as the product of the process.

Abstract: A heat reclaim system for reclaiming waste heat from a material processing line by bleeding a portion of the heated air from one or more points on the material heat processing line and directing such heated air through an economizer containing a bank of serpentine coils. Water is pumped through the economizer coils to extract heat from the air, and the heated water leaving the economizer is piped to another heat exchanger where the reclaimed heat is extracted from the water for use in other processes. More than one economizer may be provided in each heat reclaim system for receiving bleed-off air from different points on the material heat processing line, with the economizers connected in series to obtain the highest temperature difference between the air and water.

Abstract: A process for recovering iron, nickel and magnesium metal from low grade nickeliferrous ores is described. This process which requires little energy input comprises the steps of(a) grinding the ore to reduce the particle size of the ore,(b) preparing a slurry of the ground ore in sulfuric acid containing less than ten percent of water,(c) adding water to the acid:ore slurry in an amount which is effective to initiate a sulfation reaction,(d) allowing the sulfation reaction to continue utilizing the heat of the sulfation reaction, whereby water-soluble metal sulfates are formed,(e) leaching the sulfation product with water to extract the water-soluble salts of iron, nickel and magnesium from the insoluble residue, and(f) recovering the nickel, magnesium and iron from the leach solution.The desired metals which are recovered in this manner contain significantly reduced levels of undesirable silica.

Abstract: A method for recovering nickel from waste materials containing nickel is described which comprises the steps of(a) subjecting a mixture of the waste material and a nickel-containing ore to oxidizing conditions at an elevated temperature,(b) melting the oxidized mixture,(c) subjecting the melt to reducing conditions, and(d) recovering the desired nickel.More particularly, an inexpensive method is described for increasing the nickel content and/or production of ferronickel obtained from nickel-containing ores using waste nickel materials such as spent nickel catalysts. The invention also provides a novel method for recovering nickel from spent catalyst systems which otherwise often have to be discarded because of contaminants and for using the heat values of the contaminants in the process.

Abstract: A cleaning machine for removing slag from the interior of a reaction ladle characterized in that the ladle is supported in upright position on a turntable for angular indexing about its vertical axis after each vertical band of slag has been chipped or broken away from the ladle by the tool of a downwardly actuated pneumatic hammer. The hammer is swingably adjustably connected to the tip of a boom which has its upper end swingably adjustably connected to a boom carriage, the carriage being vertically adjustably guided between a pair of columns extending upwardly beyond the upper end of the ladle from a base rearwardly adjacent the turntable.

Abstract: A heat reclaim system for reclaiming waste heat from a material processing line by bleeding a portion of the heated air from one or more points on the material heat processing line and directing such heated air through an economizer containing a bank of serpentine coils. Water is pumped through the economizer coils to extract heat from the air, and the heated water leaving the economizer is piped to another heat exchanger where the reclaimed heat is extracted from the water for use in other processes. More than one economizer may be provided in each heat reclaim system for receiving bleed-off air from different points on the material heat processing line, with the economizers connected in series to obtain the highest temperature difference between the air and water.

Abstract: A pyrometallurgical process for the treatment of ores, particularly lateritic nickel ores containing nickel oxide and/or nickel silicate, employing halide and metallic iron, and optionally carbon, for extraction of the metal in concentrate form easily recoverable by magnetic separation procedures.

Abstract: A process for the production of high purity iron sulfate monohydrate from an iron sulfide mineral feed involving a leaching, purification, crystallization and dehydration procedure to recover a solution of iron sulfate containing iron sulfate polyhydrates and to convert iron sulfate polyhydrates in a series of steps to monohydrate crystals. The process can be also advantageously used with iron sulfide feed materials containing non-ferrous metals with full separation and recovery of the non-ferrous metals in the sulfide residue of the leaching and purification process of this invention. It can also be used for the purification of industrial pickle liquor solutions which can be treated with the iron sulfide mineral feed in this process leach circuit with full recovery of the ferrous and non-ferrous metals content of these solutions.

Abstract: A highly sorbent iron oxide is prepared by reducing hematite to magnetite followed by a low temperature oxidation prior to contact with sulfur dioxide. The oxidized solids obtained in this manner are a more effective form of iron oxide sorbent for the oxides of sulfur.

Abstract: An improved cationic froth flotation process for the separation of silicious gangue particles from oxidic iron mineral particles wherein the silicious particles are induced to float, and the iron mineral particles remain in suspension near the bottom of the flotation cell. More particularly, the invention relates to an improvement in the cationic froth flotation process by the incorporation of a small amount of a Group II metal salt as a modifier. The recovered iron concentrates obtained by the improved procedure of the invention are of a higher grade and contain lesser amounts of silicious material.