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ON Oct. 5, 1926, the day before the general ses-sions of the fall meeting of the American Insti-tute of Mining and Metallurgical Engineers at Pittsburgh, a round table conference on the combus-tibility and testing of coke was held at the Bureau of Mines Experiment Station. There were about fifty present, with A. C. Fieldner, chief chemist of the Bureau of Mines, as chairman. The following organi-zations were represented: American Institute of Min-ing and Metallurgical Engineers, American Society for Testing Materials, American Gas Association, Eastern States Blast Furnace and Coke Oven Association, Gas and Fuel Division of, American Chemical Society, and Southern Ohio Pig Iron and Coke Association. In opening the proceedings, Mr. Fieldner explained that the meeting had been called at the suggestion of several members of the Institute and members of other organizations. The subject is of interest to the pro-ducer and the user of coke whether it be in a blast furnace, cupola furnace, house-heating furnace, open grate, gas producer, or in a water-gas generator. There has been much confusion on this subject largely because there is no common definition of combustibility. Does the blast-furnace superintendent, the coke-oven operator, and the fuel engineer have the same under-standing of the term "combustibility"? If a common understanding can be reached, many differences of opinion will disappear. COMBUSTIBILITY OF COKE R. H. Sweetser of Columbus, Ohio, disagreed with the statement of P. H. Royster, T. L. Joseph, and S. P. Kinney in Reports of Investigations, Serial No. 2524, of the Bureau of Mines, in which it was stated that the coke-oven op-erator cannot change coke combustibility by modifying oven practice. Mr. Sweetser held that the coke-oven man can change the combustibility of coke. Blast-furnace men know that coke that will burn easily with low pressure and will. come down in the regular way in the furnace can be pro-duced from a given mixture of coal. His idea of the combustibility of coke is the rate of flow through the com-bustion zone of the blast furnace. If the coke does not pass through in normal manner it is highly incombustible. H. J. Rose of the Koppers Co., Pittsburgh, objected to being pinned down so closely on this phase of the com-bustibility and incombustibility of coke. Coke-oven men are frequently obliged to change oven conditions to make a coke which gives blast-furnace men what they want. The size of the coke and the screening have an important bear-ing on combustibility, and there are many cases on record where by simply changing the different sizes of the coke, everything worked smoothly, and that is a much more combustible coke.

Jan 1, 1927

By F. R. Brotzen, D. L. Davidson

ALTHOUGH much effort has been devoted to the problem, the nature of plastic flow in bcc metals is still not fully understood. Some of the difficulties encountered stem from the scarcity of information on orientation effects and the uncertainty as to the glide system in these metals. In an attempt to provide some of this information, the present investigation was carried out, using zone-refined molybdenum single crystals deformed in tension and in direct shear. Considerable evidence exists to indicate that the primary slip system for molybdenum is (110) <111>.1,2 Figs. 1 and 2 indicate that this is, indeed, the case for direct shear at room temperature (see Ref. 3 for a description of the shear-testing equipment and procedure). Moreover, from Fig. 2, the shear stress on the (123) is lower than that on the (112). This would be the case if, as has been suggested,4,5 slip on these two planes is in reality com-

Jan 1, 1965

By Tingyao Liu, Lihui Han, Qing Liu, Bao Wang, Teng Yang, Yong Sheng

This paper mainly investigates the mass transfer phenomena of rare-earth concentrate from leaching process in Rushton stirred tank reactor with rotate speed of 100-600 rpm. In the research, a certain amount of sphere particles with 50-450 μm in diameter is treated as the mineral particles. Comparison of laboratory experiment data with numerical simulation is performed. The results show that the critical impeller speed for complete dispersion is 300 rpm. And the maximum value of turbulence kinetic energy appeared 15 mm away from paddle, where the mixing time is decreased 55% and 80%, respectively, when mineral particles are injected into stirred tank through one or four filling ports. Moreover, with mixing process going on, the numbers of particles near the paddle region accounts for as much as 58% of the total amount. Meanwhile, following the particle diameter increasing, the particle concentration of the upper part of stirred tank reactor is increased.

Jan 1, 2015

By Renato Macciotta

The argillaceous formation known as the Opalinus Clay is host to the Mont Terri Underground Research Laboratory. The URL was developed to investigate the hydrogeological, geochemical and geotechnical properties of the formation. Underground excavations at the site are characterized by non-elastic and time-dependent deformations. Excavations trending perpendicular to the strike of the bedding presented relatively minor deformations, however, tunnels parallel to the strike of the bedding showed much larger non-elastic deformations. This paper presents an analysis of the measured response of a tunnel trending parallel to the strike of the bedding in Opalinus Clay. The measured convergence is compared to tunnel experience in weak rocks to assess the tunnel stability.

Jun 1, 2012

By B. C. Allen

The solubility of chromium in liquid silver and that of molybdenum and tungsten in liquid tin have been determined by equilibrating Ike Liquid in a crucible of the solule metal. Generally the weight of solute in solulion was delermined both chemically and from crucible weight losses. The resulting weight percent solubilily of chromium in silver as a function of absolule temperature T is given by log w = -6660/T + 4.02 in the range 960° to 1445°C, and that of molybdenlttrl in tin by log w = —5050/T + 1. 79 in the range 1200° to 2200°C. The values appear unaffected by minor changes in solute composition. Calculations aye made of the parlial molar heal and excess entropy of mixing. The estimated solubility of tungsten in tin is 0.001 pct at 2000°C. Evidence is presented that molybdenwm dissolves in tin without compound for mation and that tungsten and tin form W10Sn. RECENT developments in coatings, heat transfer, and brazing require a knowledge of equilibrium solubilities in a variety of systems at elevated temperatures. Of particular interest are solid-liquid interactions in metal systems involving dilute solutions. This investigation was undertaken since little is known about the phase relations or solubility of chromium in liquid silver or of molybdenum and tungsten in liquid tin.1,2 EXPERIMENTAL WORK As indicated in Table I, high-purity metals or those of known impurity levels were used. Crucibles were machined from chromium, molybdenum, and tungsten bar stock 1.3 cm diam and 2.2 cm long. Chromium rod was prepared by arc melting and extruding iodide process crystals.3 The five chromium impurity alloys were in the form of 0.6-cm-diam swaged rod. A Cr-0.06N* alloy was prepared by exposure to NH3 at 1150°C in a closed quartz capsule for 24 hr. Because significant nitrogen was lost during annealing in argon at 1600°C,4 the estimated level was 0.01 pct N. Chromium and Mo,W crucibles were outgassed at 1200" and 1600°C, respectively, at 3 X 10-5 mm. The solvent was placed In crucibles of the solute metal- 6 g Ag in chromium, 0.4 g Ag in the five chromium impurity alloys, and 4 g Sn in Mo,W crucibles. The silver and tin series were outgassed at 900" and 110O°C, respectively, and held at the desired solution temperature in a tantalum resistance furnace under 1.05 atm 99.995 pct Ar. An equilibration time of 0.5 to 1 hr was chosen since 0.3-, I-, and 4-hr anneals at 1235°C for Cr-Ag yielded similar results. Temperatures were measured optically to +10°C under essentially black body conditions which were checked against the melting point of silver. The Cr-Ag and Mo-Sn,W-Sn series were respectively equilibrated at 990° to 1400°C and 1200" to 2000°C. Vaporization losses were generally held to <1 pct by the argon. In the 1800" and 2000°C anneals for 0.5 hr, the crucibles were placed in tightly sealed tantalum cans which kept tin losses to <5 pct. After the anneals, the specimens were furnace-cooled. One anneal was made on small Mo-0.02 C, Mo-0.5Ti-0.lZr, and tungsten crucibles containing tin at 2200°C. The metals were sealed in an electron-beam-welded tantalum can of minimum volume. After the anneal, tin was still present in each crucible, none of which was severely attacked. After equilibration, the saturated solvent metal was selectively removed from the crucible by acid leaching. Weight losses sustained by the crucibles were determined from the initial weight minus the final blank-corrected weight after acid leaching. Chemical analyses were performed on some of the samples. Hot 1:l HNO3-H2O removed silver from chromium with the blank running <0.1 mg or <0.002 pct on measured solubility. Tin was removed from molybdenum and tungsten by hot concentrated HC1 with the respective blanks amounting to -0.004 and -0.0004 pct in the presence of tin. The insoluble residues were weighed and checked for composition. The leaching solutions contained traces of the solute metals which were analyzed by colorimetric methods, Diphenyl Carbazide for chromium, Thiocyanate for molybdenum, and Dithiol for tungsten. The total of the two percentages found from the residue and leaching solution minus the blank gave the desired solubility values. On the basis of annealing empty molybdenum and tungsten crucibles, weight losses due to MoO3 or WO3 volatilization were found to be generally 10.4 mg and affect measured solubilities by <0.01pct. RESULTS AND DISCUSSION Chromium-Silver . Since no intermediate compounds are reported to form in the Cr-An system,&apos; crucible weight losses and chemical analysis of the entire melt should provide reliable measures of the chromium in solution. Values obtained by the two methods are in agreement as shown by the results for unalloyed chromium in Table II and plotted in Fig. 1. Furthermore, the results are consistent with those previously determined by melting equilibrated silver out of the crucible and analyzing calorimetrically for chromium.&apos; On the basis of limited thermal analysis data, the solubility of chromium in silver has been quoted as 8 pct at the monotectic temperature of -1445°C.1 This investigation indicates an extrapolated solubility of 1.38 pct which is believed to be more reliable. At the eu-

Jan 1, 1968

By G W. Wilson, C Panidis

Potentially acid forming (PAF) waste rock contained in dumps formed as a result of open cut mining of metalliferous orebodies are conventionally sealed or covered using a near-saturated, low permeability compacted clay layer, protected with a mulch layer and/or vegetated growth medium. The purpose of the compacted clay layer is to limit oxygen diffusion and the infiltration of rainfall into the dump. Where the aerial extent of the PAF waste rock dump is large, or where suitable clayey material is in short supply, it may be difficult to source sufficient suitable clayey material to form the cover. The paper describes a laboratory-based investigation of combining inert waste rock and tailings to form an alternative seal or cover material. The inert waste rock was sourced from the trafficked surface of a non-acid forming (NAF) waste rock dump, with a maximum particle size of about 100 mm. This was combined with NAF thickener underflow tailings slurry in various mass ratios, and the resulting mixtures tested for their particle size distribution, compaction characteristics, soil water characteristics (relationship between suction and volumetric moisture content), and saturated hydraulic conductivity. The mixtures tested ranged in consistency from those dry enough to be compactable, to those with the consistency of wet concrete that lend themselves to placement without the need for compaction. The laboratory test results showed that the suitability of the mixtures as seal or cover materials is very dependent on the particle size distribution of the mixture, with well-graded mixtures having substantial fines performing best.

Jan 1, 2003

By R A. Eggleton and, P de Caritat, K M. Scott

The Portia Au and North Portia Cu-Au-Mo prospects are located on a magnetic structure called the Benagerie Ridge Magnetic Complex, comprising varying pyrite-bearing Proterozoic albitite, phyllite and carbonaceous phyllite. The prospects are covered by up to 75 m of Cainozoic sediments, which comprise from top down, surface soils, Quaternary sediments, the Miocene Namba Formation and the (Late-Oligocene?) Portia Unit.The Portia Unit is dominantly clay-rich with local sand-rich base and it fills palaeo-topographic lows and a palaeo-valley that incised into the weathered basement rock (saprolite). This sedimentary unit hosts the majority of the Au grains found at Portia, with additional Au grains also present in the underlying saprolite. The North Portia prospect comprises saprolite hosted Cu-Au-Mo, with elevated concentrations of As-Pb-V present in the northern part of the prospect. These two groups of elements are delineated using factor analysis, and are regarded as the pathfinder elements for the North Portia mineralisation.Secondary Cu minerals including covellite and native Cu are present in the lower saprolite, and are stable under reducing conditions in the saturated zone.In the upper saprolite (unsaturated), Cu, Au, As, Mo and Pb are associated with Fe-oxides, mainly goethite and hematite. Saprolite leached of Fe generally contains low pathfinder elements concentrations.

Jan 1, 2004

By B. Wilhelmi, W. H. Somerton

Simultaneous measurement of pore and elastic properties of socks under a wide range of triaxial stress conditions may be made with equipment and methods developed in this paper. Tests were run on three outcrop sandstones at several confining pressures and axial stresses up to approximately 80 percent of failure stress. The greater reduction in porosities and permeabilities occurred in the hydrostatic loading portion of the stress cycle, but substantial reductions in both properties did occur upon application of deviator (triaxial) stress. Triaxial elastic moduli were calculated from strain gauge measurements. Both Young&apos;s moduli and shear moduli were found to increase with increasing confining pressure. Poisson&apos;s ratios increased with axial stress but showed no consistent change with confining pressure. Only very general relations were observed between pore and elastic properties. The lesser decrease in porosity and permeability at higher stress values is related to increase in rigidity of rocks at higher stresses. INTRODUCTION Many investigators have studied the effects of hydrostatic stress on the properties and behavior of rocks. A few have studied the effects of triaxial stress fields on individual physical properties of rocks. To our knowledge no one has measured simultaneously pore and elastic properties of rocks under a wide range of triaxial stress conditions. This is the purpose of this work. Rocks exist in the subsurface under what Jaegerl refers to as "polyaxial" stress conditions (all principal stresses unequal). When two of the three principal stresses are equal, this is referred to as triaxial loading. The triaxial method of loading is most commonly used in modern testing work because experimental difficulties in measuring physical properties of rocks are greatly reduced over polyaxial testing. Although triaxial loading may not reproduce subsurface conditions precisely, subsurface stress conditions are never known precisely anyway. Triaxial testing would seem to be more realistic than testing under hydrostatic loading (all principal stresses equal) for application of results to subsurface problems. The objectives of this work were threefold: (1) to develop methods of measuring simultaneously pore and elastic properties of rocks under triaxial stress conditions, (2) to determine whether changes in these properties are of sufficient magnitude to be considered in subsurface calculations and (3) to attempt to relate changes in pore properties and elastic properties since they will have been measured at the same time under identical loading conditions. REVIEW OF EARLIER WORK PORE PROPERTIES Several investigators have studied the effects of stress on the physical properties of rocks. Fatt and Davis2 showed the reduction of permeability of rock with hydrostatic loading. McLatchie et al.3 and Knutson and Bohor4 related permeability reduction to compessibility of reservoir rock, again under hydrostatic loading. Wble,5 and later Redmond,6 evaluated the effects of applied radial pressure on conductivity, porosity and permeability of sandstones. In this latter work, no axial stress was applied. Dobrynin7 reviewed much of the previous work done . on the effects of overburden pressure on physical properties of rocks. He concluded that changes in physical properties are controlled to a large extent by pore compressibility of the rock. Several sets of curves developed from empirical relations are presented. These curves permit estimation of change of properties with net overburden pressure, knowing the pore compressibility and porosity of the rock. Net overburden pressure is defined as (Pe - 0.85 Pi ) where Pe is the

By J. Brooks

The use and application of shotcrete for ground support in the Asia Pacific Region is as diverse as the countries that make up this region. This paper will attempt to describe the many methods used on selected projects within that region. The project description(s) will include project logistics, equipment, mix design, products and application methods utilized along with specifications and performance results (where available). The author will attempt to reach a conclusive opinion on the success, or nonsuccess, of the various shotcrete methods employed and the development of shotcrete within the Asia Pacific Region.

Jan 1, 1999

By C. J. Fauconnier

The various methods of detecting fires and heatings in collieries are reviewed. The methods described range from those relying principally on human senses to sophisticated methods employing infrared technology to detect traces of the products of oxidation and combustion. The advantages and disadvantages of various gases employed as indicator gases for the early detection of heatings and fires are discussed, and recommendations are made in this regard. The operation of a modern infrared carbon monoxide detection system is described, and the differences in operation and application of telemetric systems, tube-bundle systems, and up cast-shaft monitors are discussed In conclusion, some indication is given of the capital outlay required for typical early-detection systems.

Jan 1, 1981

By Williams P. A

Tailings dams constructed by the upstream method have traditionally been built using the sand fraction of the tailings, which has automatically provided a relatively permeable embankment material, and helped provide the necessary drainage conditions which are a pre-requisite for safe and stable dam construction using this method. This paper discusses some recent trends which have resulted in proposals to use impermeable material in place of the sand fraction as the embankment material, both for the starter dam, and subsequent lifts. The consequences of these types of decisions on the overall stability of the dam are illustrated, and the need for continued monitoring of pore pressures in the tailings as the dam is raised is emphasised.

Jan 1, 1992

By P. J. Routledge

THE purpose of this paper is to discuss the practical aspects of locating gravel deposits and of establishing efficient, portable concrete aggregate beneficiation plants for use on construction projects where limited amounts of high-quality gravel and sand are required. Certain projects are listed, in order to demonstrate the wide variety of problems encountered. Routledge Gravel Contractors Limited, North Vancouver, have supplied concrete aggregate for construction projects in British Colum-bia since 1957. In tl1at year, in sup-plying aggregate for a small project at a site on the northern coast of British Columbia, our quote was as follows: Concrete aggregate to specifications, f.o.b. scow, North Vancouver$ 1.75 per cu. yd. Scowing charges to site. $16.00 per cu. yd. At that time, our company realized that more attractive quotations could be submitted if local gravel was utilized where available. Port-able equipment was then acquired and a simple screening plant (Figures 1 and 1a) was at first used. This was later replaced by heavier, more versatile equipment. The use of suitable equipment, the keeping of cartage to a mini-

Jan 1, 1962

By R. C. Lo, M. D. Scott

"This paper reviews tailings management at Highland Valley Copper, and outlines main features of its tailings storage facility enclosed between the H-H and L-L dams. Key management focusses are: energy efficiency, cost effectiveness, safety and integrity of the tailings impoundment, environmental protection, and reclamation after decommissioning. Main features of the tailings facility include: high international standards for seismic and flood design criteria, water management and water quality monitoring, operations and construction optimization, reclamation and decommissioning plan, and geotechnical challenges associated with the complex geology of the L-L tailings dam foundation.IntroductionHighland Valley Copper stores its tailings mainly in the Highland Valley tailings facility (ultimate capacity: 1.8 billion tonnes). Smaller tailings storage facilities were operated by predecessor companies: the Number One Pond, the Trojan Pond at Bethlehem and the Highmont Pond at the Highmont operation as well as backfilling the Heustis and Jersey lona Pits at Bethlehem. These areas are currently not in use, and are in the reclamation phase prior to decommissioning. This paper focusses on tailings management in the main facility. As indicated in Figure I, the facility includes three tailings dams: these are, going from east to west, the H-H, J-J and L-L Dam, named after the alignment alternatives in the initial feasibility studies. From 1970 to 1977 Canadian Bechtel Ltd. advised Highland Valley Copper&apos;s predecessor company Lornex, on tailings storage at the H-H and J-J Dams and on the L-L Dam. Since the completion of the L-L Starter Dam in 1977, Klohn Leonoff Ltd. has provided ongoing consultation and construction monitoring of the raising of the L-L and the H-H Dams. The J-J Dams is currently buried by deposited tailings. This paper reviews key tailings management focusses and main features of the tailings facility."

Jan 1, 1992

By W. W. Wen

Approximately 3 percent of the raw coal processed in U. S. Steel coal-preparation plants ultimately reports to slurry- tailing disposal. The usual disposal method is to pump the refuse slurry containing the minus-48 mesh (300 µm) refuse into dams or impoundments that are constructed of the coarse refuse. The failure of an impoundment at Buffalo Creek, Saunders, West Virginia and the sliding failure of a coarse refuse pile at Aberfan, Wales, England, resulted in an evaluation of refuse disposal methods by various regulatory agencies as well as coal producers. The result of this evaluation was the promulgation of Federal regulations dealing with the construction, operation, and final abandonment of coal refuse disposal areas. As a consequence of these regulations the use of the landfill/impoundment method of disposal became in some cases economically urlfeasible or technically impossible. U, S. Steel has studied a number of alternative methods of refuse disposal. During an investigation of mechanical dewatering with a pressure filter, Portland cement was added to the slurry to solidify the filter cake. Because of the success of the cement addition it was decided to study the stabilization of fine-coal-refuse slurry through use of cement-type additives.

Jan 1, 1979

By 1980, the U.S. mining community had reached a broad consensus regarding coal pillar design. The pillar load could be estimated from tributary area theory, and the pillar strength from empirical formulas and laboratory coal strength testing. Then the growth of longwall mining required new thinking. Recently, powerful design methods have emerged from analysis of large data bases of real-world pillar successes and failures. These include the Analysis of Retreat Mining Pillar Stability (ARMPS), the Analysis of Longwall Pillar Stability (ALPS), the Mark-Bieniawski rectangular pillar strength formula, and guidelines for preventing massive pillar collapses. Sophisticated numerical models have also helped transform the pillar design landscape. In the process, our understanding of pillar mechanics has been greatly enriched.

Jan 1, 1999

By George J. Bujtor, Anthony K. Scott, Haddon F. King

In 1982, the result of a 3-year study was published as "A Guide to the Understanding of Ore Reserve Estimation". The principal conclusions were that computation formed only part, and perhaps not the most important part, of an estimate and that the estimate should recognize that geological, mining engineering and metallurgical judgements formed an essential part of the eventual result. Subsequent expectation/realization studies of several mines have produced case histories which form the principal basis of the paper. These imply that geology is even a larger factor than thought earlier.

Jan 1, 1992

By R. W. Waytulonis

This paper is an update of the activities of the U.S. Bureau of Mines, other government agencies, and the automotive and truck industry concerning diesel emission control. Enacted and proposed regulations from the U.S. Mine Safety and Health Administration (MSHA) and developments in diesel emission control are presented in terms of their impact on underground coal, metal, and nonmetal mines. Mine air quality regulations proposed by MSHA may require the underground mining industry to comply with new standards. Some mines may be required to take additional actions to meet new diesel particulate and lower nitrogen dioxide exposure standards; however, the mining industry is in a position to benefit from emission controls developed for the on-highway diesel engine market. The U.S. Environmental Protection Agency (EPA) has enacted regulations to reduce emissions from on-highway diesel trucks and buses. Engine manufacturers have responded by developing cleaner burning engines. Fuel producers have responded by providing cleaner burning reformulated diesel fuel, and exhaust aftertreatment devices have been developed to provide additional emissions reductions. Bureau research and development projects seek to determine the advantages of using modern engines and fuels, and to evaluate the efficacy of new exhaust control devices on mining machines. It appears that the diesel engine will continue to be a practical power source for use in confined environments because no other available power source is as mobile and efficient.

Jan 1, 1993

By Roman Pyrih, Jim V. Rouse

Because cyanide is a naturally-occurring chemical, geochemical and biogeochemical mechanisms exist to retard or attenuate the movement of cyanide and its compounds in the subsurface and to degrade such compounds into low-hazard reaction products. The attenuation capacity of subsurface earth materials can be measured, predicted, and enhanced by simple and inexpensive procedures. The paper describes methods of testing the geochemical and biogeochemical attenuation capacity of the subsurface and offers general suggestions for methods of enhancing such capacity. It also presents examples of data which documents such attenuation.

Jan 1, 1991

By Donald W. Fausett

This Bureau of Mines publication presents a system of thermal decompositions providing an adequate description of the mechanism of oil shale pyrolysis. Specific rate constants for systems of thermal decompositions studied are estimated via a least-squares procedure. The estimates thus obtained provide a mathematical model of the corresponding thermal decomposition system. A model that generates a good fit to published Bureau of Mines experimental data, in comparison with other models studied, is based on a thermal decomposition system consisting of two first-order reactions and three second-order reactions. Values computed for the specific rate constants corresponding to this system are shown to exhibit a temperature dependence that is in good agreement with the Arrhenius equation.

Jan 1, 1974

By M. Arvola, A. Mäkinen, N. Isomäki

Arsenic is a compound that has no significant market value. However, it needs to be removed from ores, concentrates and other process streams because of environmental or technical processing concerns. A wide range of arsenic containing minerals exists in nature, and in many instances these minerals are also associated with the ones that have commercial value. For example, sulfide copper ores are normally closely associated with minerals like enargite, Cu3AsS4 and tennantite Cu12As4S13. After mineral processing these arsenic sources can report to the waste waters and these effluents need to be treated before discharge or recycling. Ferric arsenate precipitation is a well-established method for stabilizing arsenic in effluents. Electrochemical arsenic removal utilizes the same adsorption/precipitation ideology as ferric arsenate precipitation. Electrochemical arsenic removal, even though it is a simple process in terms of equipment, is a complex system involving chemical and physical mechanisms taking place simultaneously to remove dissolved and/or solid arsenic components from wastewaters. The whole process can be described by the following three steps: 1) electrolytic oxidation at a sacrificial anode (dissolving electrode metal, iron for example), 2) chemical reaction between dissolved iron and arsenic to form a solid precipitate and 3) aggregation of the particles to form flocs, which can be removed by known solid/liquid separation methods. Electrochemical arsenic removal is a very efficient way to remove arsenic from different waters to very low residual concentrations.

Jan 1, 2016