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By Philip L. LeHoux

"Kennecott Barneys Canyon Mining Co. is a gold heap leaching facility that has been in operation since 1989. In 1994, a flotation plant was commissioned to remove sulphide minerals from refractory sulphide ore. Tailings from the plant are mixed with oxide heap leach material in order to produce a geotechnically stable agglomerate from which the gold is leached and recovered in a conventional heap leach cyanidation process. The experience to arrive at an effective blending methodology is discussed.IntroductionAgglomeration is the practice of binding fine particles to coarser rock or other fines in order to avoid the deleterious effects of mobilizing the fines during the course of heap leaching(l-Chamberlin). Agglomeration has been considered a key component of successful operation at many heap leach sites. If the ore is of sedimentary origin and crushed, there is a high likelihood that the resulting product will contain a significant quantity of fines and a skewed gradation, that i~, a disproportionate amount of coarse and fine particles, with few in the intermediate size range. The exact methodology for determining whether the practice of agglomeration will have to be integrated into the operating scheme has been well discussed. These conditions are primarily geotechnical and geochemical. This paper will deal with the specific experiences of Kennecott Barneys Canyon Mining Company in modifying the agglomeration practices to suit evolving operational requirements."

Jan 1, 1997

By Gil Bourcier

A process has been developed for detoxifying spent potliner (SPL) in which the SPL is blended with limestone and an anti-agglomeration agent and thermally treated in a rotary kiln. The process has been proven and a commercial plant is in operation at Gum Springs, Arkansas. The treated by-product material has been delisted by the U.S. EPA and is now a potential raw material for many commercial applications. Finding uses for a non-hazardous material has many advantages over finding uses for a hazardous material like SPL. Complete usage of the by-product will complete the life cycle and eliminate any landfilling of non-hazardous SPL by-products or residues. Being non-hazardous and containing compounds used in the ceramic and numerous other industries assures many potential uses for the spent potliner by-product.

Jan 1, 1994

By C. J. Beyke

Slags and/or mattes from three secondary lead producers were studied as part of an effort to develop treatment methods for these lead-bearing residues. Each company used a somewhat different production process. Company A used a reverberatory furnace followed by a blast furnace. Company B used only a blast furnace. Company C used both a reverberatory and a blast furnace, and the scrap material was desulfurized with sodium carbonate prior to smelting. The slag matrix produced from sulfur-bearing scrap consisted mainly of iron-calcium silicates; the slag from desulfurized material was similar, but also contained sodium. In all the slags most lead was present in metallic form, often alloyed with tin, antimony, arsenic, and/or iron. Slag from Company B contained the most alloying elements, often as discrete subparticles within the lead droplets. Mattes were produced at Companies A and B; predominant phases were pyrrhotite and magnetite, while lead was present in metallic form and as galena.

Jan 1, 1995

By Mary Cunningham

The EPA and DOE have collaborated on a series of studies to evaluate the effectiveness of treatment technologies at stabilizing bulk elemental mercury and wastes containing high concentrations (i.e., with greater than 260 mglkg total mercury) and multiple forms of mercury. The data from these treatment demonstrations are intended to help EPA to determine if regulatory revisions to allow a stabilization alternative for high-mercury subcategory wastes are warranted. In addition to mercury-contaminated wastes, the disposal of bulk elemental mercury is of concern because of the excess quantity of mercury in the Defense Logistics Agency (DLA) stockpile, as well as other potential sources of excess elemental mercury. The studies evaluated the effectiveness of several technologies at: I) stabilization of mercury in a "hard-to-treat" matrix; and 2) conversion of elemental mercury into a stable waste form for disposal. A surrogate waste was designed for the study on high-mercury wastes, which included an organic form of mercury, elemental mercury, and several mercury salts in an inorganic matrix. The surrogate waste and the bulk elemental mercury were treated by the vendors, and the treated waste forms evaluated for mercury Icachability, using both the TCLP and an automated, constant-pH leaching protocol. Constant pH leaching was conducted at pH 2,4,6,8 10 and 12 for 14 days at each pH. The leaching data demonstrate that the stability of the mercury in three treated waste forms varies widely across the pH range tested. Clearly, the stability of mercury in these treated waste forms will be highly dependant on the disposal conditions. The combination of site-specific disposal conditions and appropriate treatment technology must be considered as decisions are made about disposal of high-mercury wastes.

Jan 1, 2003

By C. Gasparrini

Mineralogy may be applied to the selection of appropriate separation techniques, as well as to assist in the evaluation of problems causing loss of metals and other economically important elements during plant processing. Mineralogic studies may thus help develop techniques to optimize metal recoveries. The present paper describes how such factors as the minerals in which the elements of interest are concentrated, their chemistry, the chemistry of the associated minerals, grain size and textural associations with other minerals in the ore, may affect decisions on separation techniques for the recovery of economic elements. A number of case studies are described in which the mineralogical observation of ore samples has revealed the cause of problems experienced in the extraction of select precious and base metals, or has been decisive in the choice of appropriate techniques for recovery.

Jan 1, 1981

By J. A. Innes

"""The oxygen, next uniting with the carbon, sent up an ever-increasing stream of sparks and a voluminous white flame. Then followed a succession of mild explosions, throwing molten slags and splashes of metal high up into the air, the apparatus becoming a veritable volcano in a state of active eruption.""IntroductionHenry Bessemer F.R.S(An autobiography, 1905)Thank you Mr Chairman for the opportunity to speak: at this, the opening session of your International Symposium on the subject of ""Injection in Pyrometallurgy"". Judging from the list of papers to be presented over the next three days, the Symposium promises to provide a most valuable addition to our existing knowledge base in what is now an extremely active area of R&D investigations. Whilst we have obviously come a long way since Sir Henry Bessemer's pioneering experiments of the mid-19th century, there is still much for us to learn.Most importantly, the Symposium offers a further opportunity to acknowledge the many significant technical contributions made in this field by the Organising Committee's special guest, Professor Howard Worner - one of this country's most respected research leaders.When first approached to give this talk I had two areas of concern. Firstly, I was not entirely clear just what injection metallurgy was meant to cover. How should the overall scope of this particular subject be defined?My second concern related to Howard Worner himself - a man for whom I have the highest personal regard and who, in fact, played a most influential role in respect of shaping my own career. Having already spoken about Howard's achievements on earlier occasions, I wondered what I could sensibly add.Notwithstanding these personal reservations, I am delighted to be here with you this morning. If my thoughts on the meaning and scope of injection metallurgy appear to be slightly off-course, and if Howard should perhaps recognise some repetition in my remarks, then I hope I can be forgiven."

Jan 1, 1996

By Hans von Michaelis

There has been a renaissance in gold and silver extraction and recovery that has taken place over the last fifteen years, since the price of gold was freed from the $3510~ level. Despite major advances in such areas as carbon adsorption processes for gold recovery, refractory gold ore treatment, crushing and grinding, process control, etc., there still remain several gold and silver mineral processing frontiers. Frontiers related to environmental management present significant challenges especially in the USA. More than ever it is appropriate to optimize total economics by adopting a "systems approach" that integrates mining, mineral processing and environmental management.

Jan 1, 1993

By James J. Reilly

This paper recounts a history of the contribution of Dr. Gary Sandrock to the science and applications of metal hydrides from 1974 to 2006. It includes a bibliography that cites selected publications over the course these years and which constitutes an important public record.

Jan 1, 2006

By Md Sazzadur Rahman

Electrochemical Impedance Spectroscopy studies were conducted on two organic thermal energy storage materials; Neopentylglycol (NPG) and 2-Amino-2-Methyl-1,3-Propanediol (AMPL). The ionic conductivities and dielectric relaxation times in the low temperature ordered a-phase (monoclinic for both NPG and AMPL) as well as high temperature orientationally disordered cubic y-phase are reported.

Jan 1, 2006

By David Goodman

The typical operating conditions in Solvent Extraction plants are presented. The various materials of construction used for solvent extraction equipment are reviewed and the history of their use presented. The properties of the materials in common use today, stainless steel, thermoplastics and fiber reinforced plastics, are compared together with cost data. The manufacturing and construction aspects of these materials are discussed.

Jan 1, 2003

By Hong Yong Sohn

On the occasion of this symposium in my name, I reflect upon the contributions of my academic mentors and early associates who helped shape my professional career. I was fortunate to have these people around me during my graduate work and at the start of my professional career. In forming my view of the technical field and career, they represented academia, research institutions, industry, and different parts of the world.

Jan 1, 2006

By Hong Yong Sohn

On the occasion of this symposium in my name, I reflect upon the contributions of my academic mentors and early associates who helped shape my professional career. I was fortunate to have these people around me during my graduate work and at the start of my professional career. In forming my view of the technical field and career, they represented academia, research institutions, industry, and different parts of the world.

Jan 1, 2006

By Gary Kordosky

Equilibrium modifiers, first introduced into copper solvent extraction reagents in the late 1960?s, are widely used. The properties of various equilibrium modifiers with respect to copper extraction, selectivity, reagent stability and entrainment are discussed and some conclusions are drawn relating the structure of the modifier to the properties of the modifier. A new highly selective, low viscosity modifier is also introduced.

Jan 1, 2003

By Hong Yong Sohn

On the occasion of this symposium in my name, I reflect upon the contributions of my academic mentors and early associates who helped shape my professional career. I was fortunate to have these people around me during my graduate work and at the start of my professional career. In forming my view of the technical field and career, they represented academia, research institutions, industry, and different parts of the world.

Jan 1, 2006

By Chi Ru?an

Sollutions of ammonium chloride, nitrate and sulfate were studied in extraction of rare earths absorbed on a low-grade, kaolilnitic ore recently discovered in southern China. The results of percolation leaching tests and the recovery of the rare-earth values from these solutions are presented.

Jan 1, 1989

By Hong Yong Sohn

On the occasion of this symposium in my name, I reflect upon the contributions of my academic mentors and early associates who helped shape my professional career. I was fortunate to have these people around me during my graduate work and at the start of my professional career. In forming my view of the technical field and career, they represented academia, research institutions, industry, and different parts of the world.

Jan 1, 2006

By Patrick R. Atkins

Energy issues will have increasing impacts on decision making in all facets of society over the next few decades. Industrial users of energy and producers of products that affect energy use must be fully aware of the implications of their processes and products on the energy situation. This paper describes a model that has been developed for the aluminum industry that allows scenarios to be evaluated to gain improved understanding of possible implications for our businesses. A brief overview of the model is provided.

Jan 1, 2006

By David M. Beckwith

Increased globalization and outsource manufacturing complicate the procurement and enforcement of intellectual property rights on a worldwide basis. Recent legislative and case law developments in the United States highlight the importance of a multinational intellectual property strategy. IP lawyers David Beckwith and John Hankins will discuss planning and pitfalls in this rapidly changing trans-border environment. Topics to be discussed include harmonization with international patent laws, protecting your technology and market space with a comprehensive approach to IP, and patent enforcement issues relating to import/export of products and components in the United States.

Jan 1, 2006

By Ali Unal, Ali I. Kahveci

Alcoa developed a fractional crystallization process some 30 years ago as a method to purify aluminum. Depending on the purity of feed metal, it has been commercially used to make 3N7-6N purity aluminum. As an extension of this technology, Alcoa has experimented with purifying various aluminum alloy scrap for the purpose of recycling. Purified aluminum alloy scrap can be reused for making the same alloy. This presentation will discuss Alcoa fractional crystallization technology and its application to alloy scrap processing. Process capabilities and the partitioning of eutectic and peritectic impurities during fractional crystallization will be discussed for the alloy systems investigated.

Jan 1, 2000

By L. A. Kazanbayev

The Chelyabinsk Electrolytic Zinc Plant (CEZP) was commissioned in 1935. Over the elapsed years the Plant capacity has been increased from 10 thousand tons of zinc (1935) to 150 thousand tons of zinc (2005). The paper describes the Plant main achievements in production updating for the last 10 years.

Jan 1, 2006