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By A. Acar, E. T. Tuzcu, Y. O. Vural

"In order to sustain the operations in chromite processing plants, due to concentrate selling cost, plants are in need of optimization in terms of capacity and recovery increase. In this study, DAMA Engineering carried out a methodological study for the purpose after a detailed sampling campaign in a plant which is situated in one the main chromite zones in Turkey; 1 The current status of the plant was investigated quantitatively with the bottlenecks, Plant overall efficiency in terms of recovery, Efficiencies of the particular equipment (mill, screen, gravity circuit), 2 A new circuit was proposed with the available equipment, 3 The new circuit that is product of modeling and experimental effort, was evaluated quantitatively as if it is a running plant, After 4-5 months continuous effort, the capacity of the plant was almost doubled (37 tph to 70 tph) and the plant overall recovery was increased from 48% to 63% by grinding adjustments and additional shaking tables theoretically. It was shown that the plant may move into profit with the minimum amount investment using readily available system. INTRODUCTION TO THE CURRENT PLANT The objective of the study is to increase the capacity and recovery of the chromite plant owned by Kurmel Group, Akmetal Inc. The complete study is given elsewhere (DAMA, 2016). The plant is situated in one of the main chromite zones in Turkey; Aladag. The current capacity of the plant is around 35 tph and the overall recovery declared by plant engineer is around 47 %. The chromite plant mainly has 3 units; crushing, grinding and gravitational circuits. The crushing circuit has 3 stages; a jaw crusher, a secondary cone crusher and a tertiary cone crusher operating in closed circuit with a vibrating screen with the aperture size of 15mm. In grinding circuit, a rod mill (2.44 6m x 3.6) and a ball mill (2.13 x 2.3m) are used for primary and secondary grinding, respectively. Derrick screens are used for the size separation. Additionally, for the size classification of the system, hydrosizers are used and each size fraction is sent to the shaking table sets. The middling product of the tables is subjected to re-grinding with a ball mill with the dimensions of 2.1 x 2.9 m. The capacity and the recovery are affected by several bottle necks; hydrosizers’ pure classification, primary/secondary mill power vs capacity problems, re-grinding product’s high slime content and so on. These combined factors made the plant to run in low recovery and capacity. Hence, DAMA was asked to make a study to investigate current status of the plant and propose a new solution to increase capacity and recovery of the plant. The conceptual flowsheet of the circuit is given in Figure 1 below."

Jan 1, 2017

By J. B. Mawdsley

"The Red Lake Gold Shore mine is 4/5 mile west of the town of Red Lake, Ontario, and a mile northwest of the Howey mine. It came into production in August 1936, and in a little over 2 years produced 21,099.58 oz. gold from 83,949 tons milled.An investigation of this deposit was made by the writer during parts of September and October, 1937t. The geology of the deposit is also discussed by H. C. Horwood(2) , and the characteristics of the ore were investigated by the Bureau of Mines, Ottawa (1).The orebodies are pipe like and close together, in a north-northwesterly trending zone of dykes, veins, and shear zones in a granodiorite stock, just south of a pronounced valley with a trend of N.65°E. believed to lie along a strong shear zone and fault . The dykes, veins, and mineralization are believed to have been successively emplaced along structures having three general trends and that were due to compressive stresses that alternated, at least four times, from west of north to east of north. In common with many other gold deposits, the gold mineralization here occurred late and followed the last east-of-north stresses.WALL-ROCKSThe mine is within the Dome stock, % mile from its southeast margin. Near the mine the rock is a pink hornblende-biotite granodiorite, grading within short distances, but not abruptly, into a dark grey variety. Near the workings at least, scattered small inclusions form about ½ to 5 per cent of this body. Most of them are fine-grained, angular, or partly rounded, greenstone fragments, but some have been partly granitized and feldspar has been developed in them."

Jan 1, 1954

By N. Panteleeva, E. Konoplev, I. Michailova, S. Titkov, S. Aliferova, T. Gurkova, T. Chumakova

Cationic flotation using alkylamines and their derivatives as collectors, and characterized by high selectivity of mineral particle separation, is finding ever growing industrial application. In recent years the industrial application has been initiated of new cationic collectors - alkylmorpholines. Efficiency of cationic surfactants operation as collectors is dependent upon their colloid and sorption properties and the availability of silicate .carbonate rock-forming mineral impurities in the ore, which sorb the cationic collector. Investigations have been carried out on the influence of frothers and organic depressors with various compositions upon physical-chemical and flotation properties of alkylamines and alkylmorpholines. On the basis of these investigations requirements for organic depressor were developed and new flotation reagents were proposed (V-1 frother and KS-MF depressor). The use of new reagents enables one to decrease considerably the consumption of expensive cationic collectors and to enhance the floatability of coarse mineral particles. Data of new reagents industrial application is presented. The reagents developed can be used for flotation processing of other ores.

Jan 1, 2003

By F. C. Smyers, E. W. Merrick

ALTHOUGH the zinc and pyrite concentrates produced at Midvale go to other companies, the United States Smelting Refining and Mining Company smelts and refines its own lead. Refining is the first step of the process that is done at some distance from the mining operations, the plant being at East Chicago, Ind., an industrial center about 25 miles southeast of Chicago. For years it has been notable as being the only lead refinery in the country using the Betts electrolytic process. The original buildings, many of which are still in use, were erected in 1906 when the plant was known as the United States Metals Refining Co. In 1920 the parent company sold its copper refinery at Chrome, N. J., and since the copper refinery was also known as the U. S.

Jan 1, 1948

By Martín A. Encinas-Romero, GUILLERMO TIBURCIO-MUNIVE, María M. Salazar-Campoy, Patricia Guerrero-Germán, José R. Parga-Torres, Luis S. Quiróz-Castillo, JESÚS L. VALENZUELA-GARCÍA

Pressure oxidation is a hydrometallurgical oxidative pretreatment for refractory ores, such as sulfide ores. Here, simultaneous alkaline pressure oxidation and sodium cyanide leaching treatments were carried out on a pyritic ore from the Mulatos Mine located in Sahuaripa, Sonora, Mexico. Mineral characterization, agitation leaching, hot cyanidation under atmospheric pressure conditions, simultaneous moderated pressure oxidation and leaching, and kinetic testing results are shown. The modified variables were temperature, pressure, and cyanide concentration. Characterization indicated that pyrite was the main mineral. Simultaneous pressure oxidation and leaching experiments were conducted at a temperature range of 40–80 °C, oxygen pressure of 87.5–200 psi, and cyanide concentration of 0.8–1.2 wt% in a 2-L Parr pressure reactor. A dissolution rate of 81–86% was achieved under the following conditions: 87.5 psi, 80 °C, 0.8 wt% NaCN, for 1 h.

May 7, 2020

By Cailing Zhen, Jian Pan, Deqing Zhu, Xianlin Zhou, Yanhong Luo, Guixiang Huang

The grate-kiln process has been widely applied for oxide pellet production with the quick development of steel industry in China, but ring formation takes place which adversely affects the productivity and properties of fired pellets. Rotary kiln at high temperature seems a black box, and ring formation is difficult to measure directly by current technology. It’s of great importance to monitor ring formation during firing of pellets. Therefore, a method for estimating the thickness of ring formation in rotary kilns was studied, based on working out theoretically the relationship between ring thickness and the outside surface of the kiln, according to steady-state heat transfer across a cylinder, which provides a soft-sensing technique for ring formation at high temperature, and achieves stable pellet production .

Jan 1, 2015

By J. A. MacLellan

"CONSTRUCI'ION OF SHERRITT'S CONCENTRATORSSherritt Gordon is operating two mills north of the 56th parallel, and is presently engaged in building a third. The author was closely involved in the design and construction of all three of these concentrators.The Lynn mill is the oldest of these three concentrators-it is a 4,000 ton per day nickel-copper plant built in 1953. The Fox mill is a 3,000 ton per day copper-zinc concentrator built in 1970. The Ruttan mill will be a 10,000 ton per day copper-zinc plant scheduled to go on line in July 1973.LYNN MILL The Lynn mill including the crushing, concentrating, drying and load out plant is about 69,700 square feet or 17.4 square feet per ton per day. '!his plant was originally built in 1927 at Sherridon, 150 miles south of Lynn Lake, as a 2,000 ton per day copper-zinc plant. In 1952 the plant was moved by tractor train to Lynn Lake. The whole plant was re-oriented within the original perimeter walls as a 2,000 ton per day nickel-copper plant. This plant was expanded to 4,000 tons per day by the addition of t1-Jo rod mills and a 5-1/2 short head crusher in 1959.The Sherridon mill processed its last ore in Sherridon in September 1951 and the first load of nickel concentrate was loaded at Lynn Lake on November 9, 1953 when the railroad arrived at Lynn Lake.The site for the Lynn Lake mill was cleared of overburden in the summer of 1952 and foundations for structural steel and SO!l8 equipment foundations were poured the late summer and fall of 1952 • Steel was erected from January to June 1953. Most of the equipment came in from January to March of 1953 by tractor sleighs. Sane sleighs upset but no equipment was lest through the ice."

Jan 1, 1972

By J. C. Heter

The P.W. Gillibrand Company has been processing and stockpiling a suite of heavy minerals at its Soledad Canyon Mine as co-products with construction aggregates since 1984. The heavy minerals are composed of ilmenite, magnetitie, apatite and zircon. The source of the heavy minerals is the Precambrian San Gabriel Anorthosite Complex of the western San Gabriel Mountains. The valuable minerals are readily amenable to standard ore dressing techniques, such as, gravity, magnetic, flotation and electrostatic separation with good recovery and product quality. More than 20,000 short tons of coarse ilmenite were sold in 1990 to the export market for titanium pigment production.

Jan 1, 1992

By C. Chamberlain

The Telfer Project, Australia's newest, largest, and most remote gold mine treats 480 kt of ore grading 9.33 g/t derived from open pit mining operations. Coarse gold is recovered by gravity concentration with jigs and further upgraded wing a continuous strake launder table, and by amalgamation. Remaining gold is recovered in a cyanide circuit and incorporates flat bottom air agitators, counter current decantation (CCD) and stellar filters for clarification and precipitate removal. Overall recovery into a bullion averages 98%. The mill incorporates a number of design features that allow for maximum efficiency and security wing a minimum number of operation personnel.

Jan 1, 1983

By Zohreh Kazemi Motlagh, Virginia T. McLemore

There are more than 15,000 abandoned mine features in New Mexico. A considerable number of these mines have not been cataloged or assessed for prioritized reclamation efforts. These mine wastes can be examined as a resource of critical minerals. Many of legacy mine waste deposits have undiscovered commodities and critical minerals, due to low recovery processes during past production. In this project, Black Hawk mine wastes in Grant County, New Mexico are examined by thorough mineralogical and geochemical characterization. This project seeks to characterize and estimate the critical minerals in mine wastes of Black Hawk mine, and determine the acid generating potential of mine waste. Identifying and producing critical minerals in New Mexico may directly benefit the U.S economy and national security.

Feb 1, 2024

By T. H. Aldrich

(Chattanooga Meeting, October, 1908.) Tars paper is intended only to give a preliminary account of experiments made, and conclusions reached, concerning the treatment of certain refractory low-grade gold-ores, the profitable reduction of which may furnish a useful guide to the solution of similar mining and metallurgical problems, not only in the gold-bearing belt of the Southern United States, but perhaps in other regions also. It must be regarded as simply a ?report of progress," preceding a more elaborate and conclusive report of regular practice. The mines of the Hillabee Gold Mining Co. are located upon what is generally known locally as Hog Mountain, on the northern edge of Tallapoosa county, Ala., about 15 miles from Goodwater and 14 miles from Alexander City, stations on the Central of Georgia Railway. Gold has been known since 1839 to exist on this property, where it was discovered in that year by a man named Johnston. The property was worked for placer-gold by the old miners, and there are now the remains of four attempts to operate it by stamp-mill and plate-amalgamation. The present owners purchased it in 1896, and since that time they have experimented at frequent intervals, in order to devise a process that would satisfactorily recover the gold. In 1903 regular operations were begun. Geologically, the mountain consists of an intrusion of what has been pronounced true granite in altered sedimentary slates. The cooling of the granite produced shrinkage-cracks, which have become veins. There is considerable question as to the period of the slate formation; but it is undoubtedly, in my opinion, of Carboniferous age. The veins, about 50 in number, strike N. 60° to 80° E.; dip approximately 65° from the horizontal; vary from a few inches to 25 ft. (being in gen-

Nov 1, 1908

By K. C. Corin, M. Tadie, N. Ndamase

Fresh water conservation efforts and strict environmental regulations have forced the mining industry to reduce freshwater consumption and effluent discharge. This is achieved by recycling process water back to mining processes. The performance of flotation circuits depends on the pulp chemistry. When process water is recycled to flotation cells, organic and inorganic species that have accumulated over time alter the pulp chemistry. The presence of accumulating ionic species such as SO4 2- and S2O3 2- has been found to hinder the adsorption of collector ions onto mineral surfaces. Sulphide minerals are semi-conductors; electrochemical reactions take place on their surfaces. The adsorption of collectors onto mineral surfaces takes place via electrochemical reactions. This study, therefore, aims to investigate how the presence of accumulating ionic species at varying ionic strengths affects the adsorption of sodium ethyl xanthate onto chalcopyrite from an electrochemical perspective. Synthetic plant water comprised of single salts with varying ionic strengths was used. Rest potential measurements were conducted to investigate collector-mineral interactions in the presence of these ionic species. Microflotation tests were performed to determine whether the presence of these ionic species affects mineral floatability. Higher chalcopyrite recoveries were achieved in the presence of SO4 2- than in the presence of S2O3 2-. Rest potential measurements were found to successfully predict microflotation performance in the presence of the ions of interest. Keywords: Flotation water quality, electrochemical adsorption; xanthate collectors

Jan 1, 2020

By D. N. Hedges

This paper discusses the actual recovery and installation of a longwall in a bituminous coal mine in western Pennsylvania. The coal bed mined is in the Lower Freeport seam, which averaged 1.07 m (42 in.) in height locally. Drainage from the mine is about 13.25 ML/day (3.5 million gal per day) of water. This water deteriorates the mine's predominately fire clay bottom making it extremely difficult to move equipment. Support removal is accomplilshed by pulling the 5.44 t (6 st) shields out under their own hydraulic power and transporting them by track 8.05 km (5 miles) to the next longwall panel. This paper also discusses the changes that will be made to aid in the succeeding longwall recoveries and installations.

Jan 1, 1985

By Jerome F. Sheldon

The earliest recorded history in the use of belt conveyors in the United States is in O. Evans' "Miller's Guide" published in Philadelphia in 1795. Evans defines a conveyor as a "broad endless strap of thin pliant leather or canvas revolving over two pulleys in a case or trough." (Ref. 1) In this definition, pulleys are being used in a bulk material belt conveyor application. Pulleys used in belt drives can trace their origin back to 1200 A.D. In fact, Engineers had considerable experience designing them into drives transmitting greater horsepower than those used in the early belt conveyors. In belt conveyor application, a pulley's purpose is primarily three-fold, 1) support the belt in directional changes, as designed in the conveyor, 2) transmit driving power to the belt, and 3) guide or train the belt. There are various types of pulleys used in belt conveyor systems and these are thoroughly covered in "Belt Conveyors For Bulk Materials" prepared by CEMA, 1966. For our discussion, however, the most common used in belt conveyors are drive pulleys, snub pulleys, head pulleys, tail pulleys, takeup pulleys and bend pulleys. The drive pulley imparts the driving force to the belt and may be located at the head or discharge end of the conveyor, in return strand, or at the tailor loading end of the conveyor. A snub pulley is located near the drive pulley to provide more arc of contact between the belt and pulley for maximum

Jan 1, 1971

By Oliver C. Ralston

The Nonmetallic Minerals Division of the Bureau of Mines deals with all mineral substances not intended to be used as ores for extraction of metals, with the exception of the fuels. However, coal washing, the methods of which are highly Similar to the concentrating methods for ores, is in¬cluded In the work of the Nonmetallic Minerals Division to facilitate administration and to avoid duplication of equipment. During the fiscal year most of the work of the division was done at the experiment stations in College Park, Md., Tuscaloosa, Ala., and Seattle, Wash.

Jan 1, 1938

By Oliver C. Ralston

The Nonmetallic Minerals Division of the Bureau of Mines deals with all mineral substances not intended to be used as ores for extraction of metals, with the exception of the fuels. However, coal washing, the methods of which are highly Similar to the concentrating methods for ores, is included In the work of the Nonmetallic Minerals Division to facilitate administration and to avoid duplication of equipment. During the fiscal year most of the work of the division was done at the experiment stations in College Park, Md. Tuscaloosa, Ala., and Seattle, Wash.

Jan 1, 1938

By Kristian E. Waters, Hao Ma, Haibei Wang

Over the past few decades, ELM based separation processes have become an attractive and efficient way to remove toxic metal ions from the various aqueous waste effluent streams. This paper provides a comprehensive review of the generation, characterization, and applications of emulsion liquid membrane (ELM) from the more than 280 papers and books published so far. First, the ELM formation and the transport mechanism are introduced. Then the ELM stability and emulsion splitting methods are discussed in detail, followed by the latest research and findings of the extraction of copper and nickel using the ELM technique during the past few decades, including a thorough discussion of ELM operating parameters that impact ELM stability and extraction. In addition, the kinetics study and industrial application of this technique for the removal of coppers/nickel solutes are also presented and discussed.

Jan 6, 2023

By Ian Larkins

The Ruby Hill Mine agglomerates crushed low-grade ore (nominally -1 .5'') with high-grade filtered tailings (filter cake, nominally 80% -65#). Cement is added as a binding agent. The agglomerated ore is then conveyed and stacked on the heap. In 1998 approximately $480 000 was spent on cement for agglomeration. Cement for mill pH control and agglomeration was the largest single reagent cost at Ruby Hill. In an effort to reduce agglomeration costs a test-work program was initiated to investigate alternative binders and optimum binder additions. This paper summarizes the test­work results to-date.

Jan 1, 1999

By Qingxia Liu, Chen Tingzhong, Chen Jin, Yang Xiaosheng

It is common problem (Huan Xinsheng, etc.,l992)for most iron ore concentrators in China that the concentration of thickened tailings is lower than the need for economical transportation. To solve the problem, two methods of improving the properties of the existing thickeners and using separate thickening technique have been applied in three iron ore concentrators. However, in the case of the Daye iron concentrator a new technique of cyclone-flocculated sedimentation was developed by present authors and verified by experiments. The new technique employs efficient hydrocydone designed by authors in conjunction with a low cost flocculant named KLP.

Jan 1, 1995

The detailed engineering of a coal preparation plant is important from the point of view of optimum constructibility, operational security, ease of maintenance, operating costs, meeting environmental goals, safety, plant housekeeping and reduced corrosion and erosion. This paper reviews the several large coking coal preparation plants engineered by Fluor Australia in the past 10 years, and changes and trends apparent for detailed engineering of future plants. Areas of engineering to be covered are coal feed preparation, conveyor design, plant layout, electrics and instrumentation, noise attenuation, erosion and corrosion protection, magnetite handling, rejects and tailings disposal and coal stockpiling and blending.

Jan 1, 1982