Phosphate Rock Fluorine Removal
Numerous patents and references may be found that relate to studies of phosphate-rock defluorination processes. Most of these require sulfuric acid and heat, phosphoric acid and heat, or water vapor and heat for the defluorination reaction. One of the most thorough studies was made by K. D. Jacob and coworkers at the United States Department […]
Copper Gold Sulfide Ore – Flotation & Cyanidation Tests
Grinding the ore to minus 100-mesh gave satisfactory liberation of the minerals. Standard flotation procedure with potassium ethyl xanthate, cresylic acid, and lime produced good-grade copper concentrates with over 85 percent recovery of copper and about 60 percent recoveries of gold and silver. This stop was employed in two methods of treatment developed during laboratory testing. […]
Cornstarch Explosibility
Laboratory experiments were conducted with cornstarch to study the effects of duet concentration, moisture, particle size, treatment with oil, and admixture of calcium carbonate on the dust-explosion hazard. One series of tests were made on five size fractions of starch and on samples with four different moisture contents, all prepared from a single batch. Within […]
How to Measure Flotation Cell Aeration
Present flotation processes depend almost entirely on the buoyant properties of air bubbles to effect separations of mineral and gangue, but there is no convenient method for measuring aeration in flotation cells. Consequently the relation between aeration and cell performance has not been definitely established. In connection with a comparative study of kerosene and froth […]
Black Sand Minerals in Gold Placer Deposit
This report describes work done as part of a Bureau of Mines program to appraise the titanium-mineral resources of Idaho. The work included both field reconnaissance and a spot churn-drilling program. Much general information was available, as a result of earlier work done under the Western Radioactive Minerals Exploration Program conducted between 1950 and 1954 […]
Beryllium Determination
The main source of beryllium in pegmatite is the mineral, beryl. Many of the conventional methods for the determination of beryllium in beryl are not suitable for control purposes because of lack of speed and accuracy, especially in the range below a few tenths percent. Beryl resists the usual chemical attack and can be lost […]
How to Recover Mercury from Cinnabar Stibnite Ore
Generalized conclusions cannot be drawn from the laboratory studies about the economic feasibility of extracting mercury by a combined flotation and fluidized-bed roasting process. The 94 percent mercury recovery indicated in the laboratory compares favorably with the 90 to 95 percent recoveries usually reported by mercury-plant operators. Grinding the entire ore to liberation size, plus […]
Ferric Chloride Trap
This paper discusses the design and use of the ferric chloride trap. The operation is simple and self-adjusting. The rock-salt column is self-cleaning and will remove ferric chloride, other impurity chlorides, and dust from gaseous titanium tetrachloride. The losses of titanium are low, and the molten mixture is easy to handle. The trap is placed […]
Crushing Granite
The quarry is located in the western part of the Piedmont Plateau. Geologically, this province is described by Watson as an area of highly metamorphosed sedimentary and igneous rocks of Paleozoic and pre-Paleozoic age. The Piedmont region of South Carolina has extensive areas of granite and gneiss that are suitable for aggregate. The gneisses have […]
How to Concentrate Mercury
Most mercury ores are directly roasted or retorted for recovery of metallic mercury without preliminary concentration. Recoveries are high, often approaching 100 percent; the cost is nominal. The tenor of domestic mercury ores, however, has been dropping steadily, so that the estimated average heads are now about 0.35 percent Hg or 7 pounds per ton […]