How to Make Cement From Blast-Furnace Slag
The successful establishment of iron blast-furnace plants at Newcastle and Lithgow naturally invites attention to the economic utilization of the various products and by-products arising out of the industry. The general similarity in composition between Portland cement and iron blast-furnace slag very early attracted attention both in the cement and iron-smelting industries. Probably the first […]
Electric Gold Melting Furnace
The furnace described in this paper was installed and has been used by the writer for the melting of rich gold-bearing material, and has given complete satisfaction. It may, therefore, prove of interest to other metallurgists who are faced with a similar problem. A furnace of this type should be most suitable for the reduction […]
Lead Refining Process
The building is a lofty, well-ventilated one of hardwood frame, with galvanized-iron walls and roof, and consists of five spans running north and south, covering a total length of 230 ft. Each span is composed of nine bays of 13-ft. centres, making the total width of the building 117 ft. The refinery is situated conveniently […]
Zinc Refining
Long ago, zinc refining had not become a general practice among the zinc smelters in the United States. Such refining as had been carried on was confined chiefly to remelting very high-leaded zinc, such as third-draw metal from the retort furnaces, and slab dross, and hard spelter from galvanizing pots. In this remelting operation, the […]
How Firing of Clay Affects it Microstructures
Of the several interesting physical properties of clay which have claimed the attention of investigators in recent years, none is more important than the behavior of the material when heated to temperatures above those of dehydration. Some of the problems to be solved are: The mineralogical changes that take place in firing. The relation between […]
Precipitate Refining Method
This cyanide precipitate is unique in that it is apt to vary widely in composition in the course of very short periods of time, and a method of refining and melting that would prove highly satisfactory at one cleanup would yield almost a hopeless “mess” at a second. Table I gives a general conception of […]
Melting Points of High Fusion Temperature Metals
In this paper, it is proposed to outline a method for the determination of melting points of those metals and alloys having high fusion temperatures. The application of the method as used to determine the melting points of alloys of tungsten and molybdenum will be given. It will be seen from these results that tungsten […]
Evaluate Metal Segregation in Gold Bullion
Several years ago the writer was connected with the Mint and Assay Service of the Federal Government as Assistant Assayer at the Salt Lake Assay Office. At that time cyanide bars formed approximately half of the bullion purchased by that office. Disagreement in valuation between the producer and the office was not infrequent and to […]
Tungsten & Molybdenum Alloys
Tungsten and Molybdenum The investigation thus far had considered, both singly and in binary combination, the entire list of available metals with the exception of tungsten and molybdenum, the treatment of which, by ordinary fusion methods, was not feasible. It may be said in advance that any treatment described in this chapter as applying to […]
Casting Metal Rods
In view of the circumstance that very few important changes have been made within the last 15 or 20 years in the equipment of rod and wire mills, the description of a new process introduced by Grenville Mellen, of Llewellyn Park, N. J., to take the place of the present laborious system of producing rods […]