Oil Burning Systems of Liquid Fuels
Oil burners, oil furnaces, and methods of installation, have been the subject of many articles, but information concerning oil-burning systems, based upon scientific principles, is still in great demand, especially in the manufacturing districts of our country. Fuel oil, as it is termed (this being the residuum from oil refineries), has for many years been […]
Mining Massive Porphyry Copper Deposits
The past decade has witnessed the development and successful operation of a half dozen or more immense deposits of low-grade copper ore that occur in the Western States. In every case sufficient capital was available to carry out the development of the mines in the manner decided upon, and it is interesting to note the […]
Types of Underground Mining Method Comparison
In any discussion of Methods of Underground Mining Comparison, one is repeatedly confronted with the difficulty of dealing with so many variable conditions. It is not an exact science and in the choice of a method each varying factor has a certain weight, which, in many cases, experience alone can determine. In mathematical terms, it is a […]
Timber Support in Underground Mining
When selecting a square-set design, one should adopt the design having the fewest number of saw-cuts but still providing the maximum support. An excessive number of cuts adds little to the strength of the set, and makes erection difficult. Furthermore, it is difficult to get even contact and bearing between the many faces. (In fact, […]
Underground Mine Timbering & Support
No matter how limited their extent, few underground mining operations progress very far without requiring some sort of support. This Bulletin presents discussion and sketches as a guide for designing underground support of timber, concrete, or steel in relatively shallow workings. Because timber will satisfy most support requirements, this discussion offers methods for supporting drifts, […]
Free and Hindered Settling
In his paper entitled, Development of Hindered-Settling Apparatus, Dr. Richards has related the history of the development of the hindered-settling classifier and given illustrations of the several types of this apparatus which he has designed. An earlier paper, Close Sizing Before Jigging, shows the nature of the hindered-settling phenomenon and the results which it produces. […]
Heat Treatment of Steel Castings
In an effort to employ cast steel of a stronger structure than that found in the annealed steel castings, the possibilities of heat treatment which will increase the strength without materially decreasing the ductility may be resorted to. The following abstracted report (which is a brief outline of what has already been done by the […]
Round Tables Recovery of Minerals from Fine & Slimes
During the last half century a great amount of ingenuity and energy has been devoted to the invention of appliances for the recovery of valuable minerals from very fine sands and slimes. The reason for this is that in almost every dressing plant the greatest losses of values, considered relatively as well as absolutely, occur […]
California Gold Dredging
Gold dredging has won an important place in the industry of mining, and it has done so by right of hard-earned merit. Probably no branch of mining has come so prominently to the front in so short a time; by proving its commercial value it has opened to the financier an opportunity for safe and […]
Cyanide Destruction Hypochlorite / Chlorine
In the Cyanide Destruction by Hypochlorite reaction, the pH has a strong inverse effect on the ORP. Thus, wastewater treatment facilities must closely control the pH to achieve consistent ORP control, especially if they use hypochlorite as the oxidizing agent. Adding hypochlorite raises the pH, which, if unchecked, lowers the ORP. calling for additional hypochlorite. Controlling […]