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By Botao Lin, Yan Jin, Hongjuan You, Jingjun Pan, Huiwen Pang, Mian Chen, Sen Chen

"Steam Assisted Gravity Drainage (SAGD) has become the mainstream technology for ultra-heavy oil recovery in Xinjiang oilfield, the success of which depends heavily on shortening of preheating period as well as forming homogeneous and highly permeable zone in land-facies oilsands layer. Towards this aim a special hydraulic fracturing process is required, which is accomplished through controlled water injection to a pair of horizontal wells in order to create homogenously distributed microcracks in the zone between the two wells. The associated mechanical response, however, is unclear for land-facies Karamay oilsands that is loose in texture. In this regard, this research utilizes a triaxial test system on cylindrical specimens extracted from field-collected oilsands cores. Isotropically consolidated drained triaxial compression tests are conducted on both saturated and unsaturated specimens so as to investigate the mechanical response of oilsands at different spots relative to the wellbore. Moreover, acoustic emission and fast pulse-decay permeability are performed to monitor fracture development and permeability evolution. Based on these experimental studies, the mechanism of dilation in oilsands is comprehensively analyzed. The findings reveal distinctive behavior between the saturated and unsaturated specimens as respect to dilation, porosity/volumetric evolution and change of permeability. It is also found that shear bands can be created upon shearing on triaxial specimens, rendering porosity or volumetric strain the factor that is more proper for evaluation of stimulation efficiency in the field.INTRODUCTIONXinjiang oilfield is widely known for its abundant deposit of heavy and ultra-heavy oil that has been estimated to be several hundred million tons. The ultra-heavy oil deposit located in Fengcheng region of Karamay at the northwestern part of the Junggar Basin, Xinjiang, China, has over 360 million tons of resource (Yuan et al. 2013). The resource is deposited in depths from 180 to 450 m and has viscosity over 100, 000 mPa•s at a temperature of 50ºC, bringing technical challenges to recovery activities."

Jan 1, 2015

By C. Dorfling, M. Tadie, S. Grobbelaar

The physicochemical properties of the complex electrolytes used in direct copper electrowinning are an important consideration for the development of a high-fidelity model of the process. Direct electrowinning electrolytes typically contain a high background of metallic impurities. The effect of metallic ions on the properties and accompanying change in the limiting-current density for copper reduction have been the subject of several studies. Although various empirical correlations have been published for describing the physicochemical properties of electrowinning electrolytes, the correlations are only applicable to a limited range of conditions and cannot be extrapolated without further validation. Consequently, in this paper we validated existing physicochemical property correlations for the full range of operating conditions applicable to direct copper electrowinning and developed a new correlation for predicting the associated limitingcurrent density for copper deposition. Following, we evaluated the benefit of using the validated correlations as a component of a dynamic electrowinning model.

Jan 1, 2023

By E. M. Norris

Phosphate deposits are distributed widely over the earth's surface. Of the known areas of deposit, eight fields are of particular interest because of their vast reserves of high grade phosphatic material and the volume of their production that goes to the world's great consuming areas. These fields, in the order of their present economic importance, are situated respectively in Florida, French Morocco, Kola Peninsula of U.S.S.R., Tunisia and Algeria, Tennessee, Montana-Idaho-Wyoming-Utah, Ocean and Naru Islands in the Gilbert group, and in Egypt. The Rocky Mountain deposits have a comparatively low ranking in the phosphate trade of today, but this field contains one of the largest known reserves of phosphatic material, associated with which are recoverable trace minerals, which are of increasing importance in our national economy. The first discoveries of phosphate rock in the western states were recorded in Cache1 and Rich2 counties in Utah, respectively in 1889 and 1897. Mining operations were begun on these deposits near Montpelier, Idaho, in 1906. During the latter year geological studies of the phosphate beds were started by Weeks and Ferrier of the U. S. Geological Survey. These studies have been continued to the present day by a distinguished roster of the Survey's technicians. As a result of this systematic exploratory program, the Survey has published a series of bulletins, papers, and maps, which provide the mining public with a comprehensive study of the exposed

Jan 1, 1949

By D. F. Zhang, X. Q. Jiang, N. Tahreen, D. L. Chen, F. S. Pan, D. Y. Li

Alloying with rare-earth elements has been proven to be an important tool for magnesium to achieve superior properties via texture randomization. The role of yttrium in texture weakening and the link between texture and formability are fairly well known. Since annealing is a vital part of metal processing which could significantly contribute to ductility, it is important to ascertain the impact of annealing in terms of texture change. Also, an understanding about texture development during pre- and post-deformation annealing is essential to improve the industrial deformation processing as texture is closely related to formability. While there is independent information in the literature regarding the effect of rare-earth addition and heat treatment on the texture formation, no systematic studies have been reported on the collective impact of yttrium addition, annealing and deformation on texture evolution. The present study was, therefore, aimed to identify the inter-relationship among texture evolution, yttrium content, heat treatment and deformation behavior in an extruded Mg-Zn-Mn-Y alloy. Annealing at 450°C for 1 hour and uniaxial compression tests at a certain amount of deformation were performed. The deformed and annealed samples were then subjected to annealing and compression test, respectively, followed by texture measurements. It was observed that yttrium addition effectively weakened the crystallographic texture in all conditions, which was evident from the changes in the microstructures and textures.

Jan 1, 2015

By Thomas H. Dubaniewicz

Fiber optic systems are being deployed in locations where explosive gas atmospheres are normally present or are present under fault conditions. The National Institute for Occupational Safety and Health, Pittsburgh Research Laboratory (NIOSH, PRL) conducted a study of laser safety in potentially flammable environments. Researchers conducted experiments to estimate the mean and standard deviation of laser powers needed to ignite 6% methane-air atmospheres using single mode optical fiber tips covered by two types of iron oxide (Fe304 and (FeMn)203) mixed with a ceramic adhesive. The iron oxides, heated by a 1064 nm continuous wave laser, ignited the methane-air mixtures ,at similar powers. The minimum igniting power and maximum non-igniting power (10 tests) were 407 and 350 mW, respectively, using a 62.5 pm fiber. Laser beams guided by 125 and 80 pm diameter cladding single mode fibers produced similar methane-air igniting powers. Ignition was not observed using coal particles at powers that produced ignition with the iron oxides. Threshold ignition delays using the single mode fiber were approxinlately proportional to the inverse square of the igniting power. Ignition delays were significantly longer than the reported activation time for a comnlercial fiber optic power limiter. Comparisons are made with the results of other researchers. Published by Elsevier Ltd.

This summary of State laws or explosives was compiled primarily to ascertain what subjects relating to their control have been acted upon by each State legislature and, in general, how they have been treated. It does not include any legislation passed after 1942, or any proclamations, regulations, or administrative orders. It does not purport or attempt to be authoritative. If any problem arises involving interpretation of the statutes of any particular State, the original source must be consulted for the exact words used by the legislature. This summary, however, will be useful In determining whether relevant statutes exist, and In locating them quickly,-with a minimum of effort. It will be of value also in comparing statutes in one State with similar statutes in other States to determine what construction has been placed upon them by the courts of those jurisdictions or to contrast the varying provisions of many States upon a similar subject. To make these comparisons easier, the statutory provisions for each State have been grouped under several major topics in outline form. Although this sometimes has resulted in disruption of the continuity of individual acts, the increased general clarity and availability of comparable sections have more than justified the procedure followed.

Jan 1, 1943

By AIME AIME

AT the seventeenth National Metal Congress, held at Chicago, Oct. 1-3, the Iron and Steel Division and Institute of Metals Division participated with the American Society for Metals, American Welding Society, and the Wire Association in one of the most successful meetings ever held. The total attendance at the technical sessions and the scope of and interest shown in the exhibits at the Exposition were greater than at any of the "Metal Weeks" since the depression began. The Iron and Steel Division held two all-day symposia and one general session. The latter, at the International Amphitheatre, Wednesday afternoon, was the only one poorly attended. This was attributable, at least partly, to the location of the meeting roan.

Jan 1, 1935

The following pages discuss the objectives, the background, the scope and a statement of the problem of the study of methods to improve the pillar extraction practices in underground coal mines. 1. OBJECTIVES The objectives of this project were: ? to determine the principal factors contributing to high accident frequency and severity in both conventional and continuous mining operations; ? to compare and evaluate the safety aspects of the "open end" and "split and fender" systems of pillar mining; to establish basic data required to decide what constitutes an adequate pillaring plan that will optimize efficiency, recovery, and safety; ? to determine what measurements or information should be collected, (e.g. roof sag, pillar stress,) to make on-the-spot judgment of impending roof or pillar collapse; ? to make recommendations to improve existing methods or to insure proper techniques are implemented, and ? to suggest areas where additional studies or new research may be of value.

Jan 1, 1975

By G. Mucsi

This paper deals with the laboratory investigation of cathode ray tube (CRT) glass based glass foam, a relatively new product so called ?Geofil bubbles?. The main process engineering material properties of raw materials, such as particle size distribution, moisture content, density and specific surface area are shown. Then the preparation of raw cathode ray tube glass waste is presented including the following steps: crushing in impact crusher, grinding in laboratory scale ball mill, mixing, pelleting and sintering. We found that it was possible to produce foam glass (with proper mechanical stability and particle density) from the investigated waste CRT glass. The material characteristics of the final product strongly depend on the sintering conditions. Optimum conditions were determined particle size fraction was found to be 4-6 mm, temperature 800 0C, residence time 7.5 min. Keywords: waste CRT glass, grinding, pelleting, sintering, glass foam

Sep 1, 2012

By Edward F. Divers

Tills U.S. Bureau of Mines report briefly evaluates the advantages and disadvantages of basic dust control techniques presently used by U.S. coal preparation and mineral processing plants. These include ventilation, baghouse-type collectors, wet scrubbers, electrostatic precipitators, source control, sprays, good housekeeping, and personal protection devices. Two specific problems in these types of operations are also considered: dust collector system duct clogging, and control room dust control. Information provided in this report results from dust control research projects conducted by the Bureau at various coal preparation and mineral processing plants over the past decade to reduce workers' dust exposure. These studies indicate that plant ventilation systems normally provide the most cost effective method for dust control. Baghouses and scrubbers were also effective in specific applications, and examples of each are given. In extreme dust conditions, personal protection devices, such as respirators or the dust helmet, can also be highly cost effective.

Jan 1, 1990

By Eric Klaffenbach

Valorization of slag from metallurgical industrial processes becomes ever more important as this may help optimizing and reducing the use of natural resources such as rock and sand. In view of this objective, metallurgical processes have to be analyzed in order to modify the slag composition so that it will meet the expected requirements of potential users of these resources. This paper gives the results of a thermodynamic analysis of the flash smelting process to understand the impact of operational parameters on slag chemistry and elemental partitioning in the process. It is shown that an increase of the matte grade and temperature leads to higher deportment of Pb, Zn and As to the slag. With increasing matte grade the volatilization of these elements decreases. Furthermore, the results indicate an increasing solubility of Cu and S in slag at higher temperatures.

By M. Elbert Nigri

Radioactive wastewaters from nuclear source of electrical energy production need to be treated and disposed of properly. Sr, Ca, Mg and Ba are common elements in this effluent, which can cause incrustation in process equipments and being unsafe to human health (90Sr). Fixation of CO2 can be applied to remove the ions mentioned before and to provide a solution where CO2 is sequestered and the deleterious elements precipitated, becoming one of the possible steps to reuse the water into the process. Moreover, removal of several metals from distinct wastewater has been evaluated using bone char through adsorption. The chemical similarity between calcium and strontium makes the exchange of these two metals favorable in the hydroxyapatite structure contained in bone char. This paper evaluated the combined action of precipitation and adsorption process with injection of CO2 and bone char addition in simulated nuclear wastewater. Removal levels of 89.0% (Sr) and 83.3% (Ca) were obtained in the combined process. The presence of bone char as seed increased the precipitation kinetics, allowing a Sr removal of 85.2% in five minutes, higher than 75.3% obtained in absence of seeds. However, removal of 91.6% (Sr) and 89.8% (Ca) were obtained in absence of seeds at 24 h. Analysis of solids have evidenced that CO2 was consumed to precipitate the metals as carbonates, since the hydroxides are formed at higher pH’s.

By D. E. Roberts

Over 425 million used automotive oil filters are discarded in the United States each year. Estimates prior to this research claim that 10% are recycled with the remainder typically being landfillcd. Surveys conducted with ferrous scrap users and oil filter processors as part of this research reveal that at least 15% are currently being recycled as ferrous scrap. Oil filter scrap is not being used by many operations because of concerns with scrap consistency and quality. These concerns stem from trials conducted in the infancy of the oil filter recycling movement. Consistent scrap quality depends both on the content of the used oil filters and the processing technique used to produce the scrap. Technology has advanced since the first recycling trials were conducted by steelmakers. Several different types of scrap are available, including pucks, bricks, cubes, and shred. This research conducted at the University of Missouri-Rolla investigated the content of used oil filters and compares the recyclability of different oil filter sizes and designs. Filters vary by application and vary between manufacturers for a particular application. An understanding of the scrap itself as well as the concerns and problems of both oil filter recyclers and oil filter processors is necessary to increase the number of used oil filters being recycled.

Jan 1, 1996

By Andrew Case

The Port Nickel facility in Braithwaite, Louisiana, is known for pioneering hydrometallurgical processes for the 'separation and recovery of nickel, cobalt and copper. Ten years ago, in 1985, a new CRI-MET process for the recovery of molybdenum, vanadium, nickel, cobalt and alumina from spent catalysts was developed and implemented. Spent- catalysts from the petroleum industry consietute the majority of feed. These are not only a valuable-source of metals, but due to EPA regulations are frequently classified as hazardous under RCRA. Molybdenum and vanadium are selectively leached in an oxidative hydrothermal step. Alumina is then extracted in a caustic digestive leach. The unique technology produces four primary commercial products l molybdenum trioxide, vanadium oxide, aluminum trihydrate and nickel-cobalt concentrate. This paper discusses the process, modifications. during ten years of operation, and the relationship of these modifications to the future of the catalyst recycling business.

Jan 1, 1995

By E. H. Crabtree

This paper traces the experimental and pilot plant work completed by the authors since 1939 including the various methods which have been developed in applying coarse activated carbon to cyanidation. The methods and results developed by the authors in desorbing gold and silver from carbons are given and the possibilities for the re-use of the desorbed carbons are discussed

Jan 1, 1950

By Fan Yang, Zhiping Wen, Tiancheng Nie, Jinhe Pan, Ruibo Jia, Changchun Zhou

Rare earth elements have important strategic significance and economic value, and the rare earth elements in coal resources have considerable development potential. This study took coal refuse in the Jungar area of Inner Mongolia, China, as the research object, and investigated the occurrence modes of rare earth elements. A special sequential chemical extraction experiment was designed, and the results showed that the rare earth elements in coal refuse mainly occur in silicate and aluminosilicate form, accounting for approximately 65% of the total rare earth elements. According to the results of SEM-EDS, micro morphology of the sample belonged to the lamellar structure of clay minerals, and Al, Si, Fe, S, Y, and La were all present in the sample. Through SPSS software analysis, rare earth elements have an obvious linear positive correlation with Al, Si, and Fe elements, and a negative correlation with S elements. The rare-earth element occurrence mode in coal refuse can provide a definite theoretical basis for the later extraction and enrichment work.

Feb 18, 2022

By John Batchelder

The Copper Canyon Cu-Au-Ag deposits include two geologically distinct hypogene ore bodies developed primarily in late Paleozoic rocks adjacent to a 38-m.y.-old potassic-altered granodiorite, whose emplacement seems to have been controlled largely by the Virgin fault, a north-striking normal fault. Widespread but subeconomic concentrations of sulfides as fracture and cavity fillings in skarn apparently preceded the final intrusion of the granodiorite. In the west ore body, metals reached ore-grade concentrations through the massive replacement of andradite by chalcopyrite, pyrrhotite, and pyrite mineral assemblages. The east ore body probably formed after the granodiorite reached its present level. Calculated 6dD values of water in equilibrium with primary and secondary biotites range from -76 to -99 per mil at temperatures indicated by d180 values from coexisting quartz and biotite. The lightest values are in secondary biotite from the east ore body. These data suggest that fluids associated with potassic alteration here were most likely composed of magmatic water mixed with some meteoric water.

Jan 1, 1976

By Charles L. Harness

Magnesia (MgO) has a variety of uses, and it has become increasingly important as a war material because of the imperative demand for refractories to line metallurgical furnaces, and because magnesia is used to make the in aircraft and other implements of warfare. Magnesia occurs as an integral part of nearly 60 minerals, but it is extracted commercially from only a .smaller number, of them. The present commercial sources are magnesite, brucite, dolomite, raw sea water, sea water bitterns, and well brines. Magnesia Raw Materials Magnesite magnesium, carbonate MgCO3, theoretically contains 47.8 percent MgO and 52.2 percent CO2. There are two varieties of magnesite, crystalline and cryptocrystalline (dense or amorphous). The latter type, though, not so plentiful as the former, is generally purer. It resembles unglazed write pottery in texture, whereas the crystalline variety is generally dark and granular, though the color may vary. The principal domestic deposits, of crystalline magnesite are near Chewelah, Stevens County, Wash. (which has supplied most of the magnesite mined in the United States), in the Gabbs Valley area of Nevada (near Luning); and in Llano County, Tex. Crypto-crystalline magnesite occurs principally in California. Magnesite occurrences have also been reported in several other States, including New Mexico, New York, New Jersey, Pennsylvania, Massachusetts, Vermont, and Maryland, but these deposits have not been developed commercially.

Jan 1, 1943

By Zhihe Dou

SHS reaction system has advantages of heat flux density, energy concentration and reaction speed, with sufficient conditions in thermodynamic and kinetic reaction. This paper invented a new technology of SHS metallurgy of preparing melting point alloys and refractory compounds using its own chemical energy. SHS-leaching process for preparing nano boron powder or ultrafine boride powder and SHS-casting process for preparing titanium-based alloy and immiscible alloy were studied. The results indicate that highly active boron powder of greater than purity of 93%, particle size less than 100nm and purity greater than 98.5%, particle size less than 400nm REB6 can be prepared. With SHS-Casting process, the oxygen content of less than 0.59% ferrotitanium, oxygen content of less than 0.5% titanium alloy and ?40-80*100mm large size of CuCr, Cu-Fe alloy ingots were prepared. This technology has greatly enhanced the thermal reduction method added values of preparing metallurgical products and its competitiveness.

Jan 1, 2014

By A. Kontopoulos

The Olympias Mine in Northern Greece is producing an extremely refractory gold-bearing arsenical pyrite concentrate, containing on the average 41 3 S, 40 3 Fe, 10-12 3 As, 25 ppm Au and 35 ppm Ag. During the process selection stage, more than a dozen alternative technologies? were considered and an in-depth analysis was prepared for the three most promising, ie roasting, pressure oxidation and biological oxidation. Detailed capital and operating cost estimates were prepared, based, where appropriate, on laboratory and pilot-plant tests. A number of criteria was used for process evaluation and selection, including capital and operating costs; environmental impact, gold' recovery, stage of development, etc. Based on the above evaluation, the Sherritt Pressure Oxidation Process was finally selected. A detailed description of the process selection stage, supported with laboratory and pilot-plant test results on many of the processes considered, will be? presented.

Jan 1, 1989