How Plastic is Recycled

This is the age of plastics. Plastics are rapidly replacing metal, glass, and wood in parts of appliances, automobiles, prepackaged consumer goods, pipe, beverage containers, and furniture. The total sales of U.S. plastic for 1972, as shown in figure 1, was 24.19 billion pounds versus 19.9 billion pounds during 1971, an increase of over 20 … Read more

Chalcopyrite Sulfuric Acid Leaching Kinetics

Renewed interest in hydrometallurgical recovery of copper from copper sulfide during the past decade has resulted from demonstrated increased copper production from low-grade copper ores and interest in the development of non-smelting techniques. Of the sulfide minerals of copper, chalcopyrite (CuFeS2) merits special attention because of its relative abundance and because it is generally the … Read more

How to Steam Cure Bricks

In the processing of numerous types of minerals to recover their values, enormous tonnages of gangue materials are produced and discarded to storage areas near the processing plants. In this country, primary copper producers alone produce 125 million tons of tailings per year. Zinc, lead, asbestos, and roofing granule operations also produce large tonnages of … Read more

Tailings Pond Seepage

This report is a sequel to earlier Bureau of Mines investigations which indicated the need for a seepage environmental research investigation relative to the slime zone of a typical tailings pond. In the previous studies, slope stability and location of phreati.c surface were of prime concern; consequently, only the outer portion of the pond embankment … Read more

Hydraulic Backfill Support

Mining companies have been confronted with a multitude of production problems in their endeavors to extract maximum quantities of ore at minimal costs. These problems are further compounded by the harsh mining conditions of deep vein operations, such as those found in the Coeur d’ Alene mining district of Idaho. One of the major obstacles … Read more

Underground Mine Design

The minerals industry in the field of Underground Mine Design is presently faced with the problem of meeting a rapidly increasing domestic and foreign demand for its mineral resources. This increased demand has added to the problems already plaguing the industry increased land, labor, and material costs; increased foreign competition; more rigid Federal and State … Read more

Mill Tailings Dam Stability

The reconnaissance-level investigations were carried out to gather supplemental data to the in-depth studies of Kennecott’ s Magna and Phelps Dodge’s Morenci tailings deposits and Kennecott’s Chino leaching dump. The data were obtained by personnel of W. A. Wahler and Associates to determine to what extent the disposal systems and techniques used at the three … Read more

Rapid Particle Hydrosizing Size Analysis

The knowledge of particle size distributions is a critical factor in the monitoring, control and optimization of many processes. This is particularly true of the mineral beneficiation industry, where comminution, the reduction of particle size, accounts for a major source of the processing costs. As an example, it is not uncommon in current taconite operations … Read more

How to Analyse Blast Furnace Slag

From May 1951 to March 1967, the Bureau of Mines, as part of its iron and steelmaking research program, operated a series of experimental blast furnaces. The first furnaces were located in Pittsburgh; later furnaces were constructed and operated at the Bruceton, Pa., facility just outside of Pittsburgh. With these furnaces, because of the shorter … Read more

How to Recover Zinc & Lead from Brass Smelter Dust

The recovery and recycling of metals from process wastes is a major research effort of the Bureau of Mines. The present work was undertaken by the Rolla Metallurgy Research Center to develop data that could be used in a pyrometallurgical process to recover zinc and lead from the flue dust generated in the secondary smelting … Read more