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By L. A. Clark, G. H. R. Burrill

"Most unconformity-type uranium deposits in Saskatchewan occur within a few tens of metres above and/or below the basal unconformity of the 1,45-b.y. Athabasca Sandstone. Graphitic basement rocks coincident with post-Athabasca faulting or brecciation at or near the unconformity are important in localizing uranium deposits which form as tabular, ribbon-like bodies with grades averaging over 2 per cent uranium and containing up to 50,000 tonnes UJOs. Some of these deposits have similar contents of nickel and arsenic.In the genetic model proposed to explain these deposits, traces of uranium were leached from the sandstone and weathered basement rocks by oxidized formation waters sweeping through the sandstone and along brecciated faults. Over basement meta-petites, a thick clay regolith adsorbed uranium from the solution. Thus fixed, the uranium was reduced through an indirect reaction with graphite, possibly involving methane. The clay mineral surfaces were thus continuously cleared to allow further adsorption. Basement faults localized along weak graphitic units were re-activated, offsetting the sandstone formation, probably at the time of an early uranium deposition about 1.2 b.y. ago, and served as vents for spent ore solutions. Fluid convection was induced by topographic relief and/or crustal heating from radioactive decay in basement plutons or mantled Archean domes with uranium and/or thorium contents a few ppm above those of adjacent rocks. Heat from radioactive decay within the incipient uranium deposit would develop in about a million years. The self-generating convection cell would continue uranium deposition until all permeability was plugged by minerals. In some instances, convection was re-initiated after subsequent faulting and brecciation. While some deposits were further enriched, heavy flows of oxidized fluids re-dissolved and partially depleted other uranium deposits.The East Alligator Rivers uranium deposits in Northern Territory, Australia, occur within Middle Proterozoic quartzchlorite and quartz-muscovite schists overlain by sandstone. Highest grades occur in silicified breccias where carbonate beds were leached out. Mineralization ages are both pre- and post-Kombolgie Sandstone, but, to date, no significant uranium mineralization has been encountered in the sandstone. There are many general similarities with Saskatchewan deposits, but important differences in detail."

Jan 1, 1981

By Seungwoo Park, Whuisu Shim, Roe-Hoan Yoon, Kaiwu Huang

"A comprehensive froth model has been derived from first principles. It is based on predicting the kinetics of film thinning in the presence of particles of varying sizes and surface hydrophobicity. According to the Reynolds lubrication theory, the thinning of a horizontal film is driven by the excess film pressure (p), which is determined by the capillary pressure (pc) and the disjoining pressure (II). In the presence of particles, macroscopic capillary pressure (pc) is affected by the local capillary pressure (pc,local) in the vicinity of a particle and the number of particles in the film (N1,film), which in turn vary with the hydrophobicity and size of the particles. The Reynolds equation corrected for pc,local and N1,film is then used to predict the time (or froth height) at which a film is thinned to a critical rupture thickness (hcr), which in turn can be predicted using the Vrij’s capillary wave model (1966) after a modification to incorporate the contributions from hydrophobic disjoining pressure (IIhp). The model can predict bubble coarsening represented by the bubble size ratio between the top (d2,t) and bottom (d2,b) of a froth as functions of particle size and hydrophobicity, ? -potentials, frother dosages, froth height, gas flow rate, salt concentration, etc. The model predictions have been verified in experiments.INTRODUCTIONFroth flotation is regarded the best available technology today for upgrading minerals and coal fines. In the pulp phase of a flotation cell, air bubbles collect hydrophobic particles dispersed in it and rise to enter the froth phase on the top. Once in a froth phase, the bubbles coalesce with each other and become larger, resulting in a decreased bubble surface area. Under conditions of limited surface area, less hydrophobic particles drop off the bubble surface and return to the pulp phase. Thus, bubble coarsening provides a useful mechanism of increasing product grades. On the other hand, uncontrolled coarsening results in a decrease in bubble carrying capacity and hence throughput."

Jan 1, 2016

By Suzie Poulin, N. Geoffroy, G. P. Demopoulos

Most metallurgical industries generate toxic waste that must be treated prior to being released to the environment. However, in a lot of cases, the waste materials are poorly characterized or the analytical results are not well interpreted. These shortcomings often result in the development of inefficient industrial procedures, thus causing economic waste and difficulty meeting environmental regulations. Fortunately, a wide range of analytical techniques are available to guide researchers and engineers into making sound process development decisions. In this work, an industrial selenium and mercury removal process is used as an example to illustrate the application of X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) coupled with Energy-dispersive X-ray spectroscopy (EDX) and powder X-ray diffraction (PXRD) on solid waste. Furthermore, samples of analytical results are presented and interpreted and the modifications to the industrial process that resulted are explained. Finally, a brief description of the advantages and limitations of the aforementioned analytical techniques is given with an emphasis on industrial solid waste material.

Jan 1, 2011

By D. F. Sherwin

"THE AREA which is described in this paper (Fig. 1) includes the continental margin of eastern Canada extending from the Gulf of Maine to the north edge of the Grand Banks, which, including the continental shelf, slope and rise, comprises an area of about 600,000 square miles. The paper is intended to give a background of the geological setting of this region in the context of its ultimate potential for oil and gas reserves in close proximity to the Nova Scotia energy market.HISTORY OF EXPLORATIONThe history of geological exploration of this area really began in 1878, when U.S. fishing boats brought back samples of rock recovered in trawls from their expeditions to the long-famous fishing banks off Canada's East Coast. Tertiary and Cretaceous fossils recovered from these samples indicated that the eastern Canadian continental shelf was actually the submerged northern extension of the Atlantic Coastal Plain."

Jan 1, 1972

By C. Yoo

"Geosynthetics engineering has made phenomenal advances during the last decade in areas of manufacturing as well as practical applications. As a result, geosynthetics are now being recognized as essential construction materials that can be used to facilitate construction, ensure better performance of the structures and reduce the long-term maintenance in routine civil engineering works. The creative use of geosynthetics in geo-engineering practice is expected to continuously expand as innovative materials and products are becoming available. In this paper, a wide variety of geosynthetic products available to geoengineers to solve a wide range of problems are briefly presented along with their functions and possible applications. Fundamentals of geotextile filter design principles are then introduced for use in the tunnel drainage system. Practical applications of geosynthetics relevant for tunnel engineering are also highlighted with emphasis on the issues associated with the geotextile filter application for use in the tunnel drainage system.INTRODUCTIONGeosynthetics have emerged as essential engineering materials in a wide range of civil engineering applications, e.g., transportation, geotechnical, geoenvironmental, hydraulics, and private development since the first geosynthetic conference in Paris, 1977 (Koerner 2012). Due to their costeffectiveness, ease of installation, and well established mechanical and hydraulic properties, geosynthetics are now playing important roles in the field of geo-engineering.As indicated in the 9th Bucahanan Lecture paper by Holtz (2001), major developments in civil engineering have only been possible with the parallel developments in the technology of construction materials. For example, larger scale structures became possible with the help of developments in concrete, reinforced concrete, and prestressed reinforced concrete technology which replaced wood and building stone as construction materials. The best example of a parallel development in geo-engineering between the material and the geotechnical application may perhaps be the soil reinforcement technology which has a direct analogy with reinforced concrete as a polymeric reinforcement material provides added level of tensile resistance and stability to soils that have little to no tensile strength, thus giving additional margin of safety."

Jan 1, 2015

By L. I. Kiss, S. Perron, S. Poncsák, A. Perron

Aluminium industry has an increasing interest in the diminution of the energy consumption of the Hall-Heroult process by the reduction of the anode bottom covering with gas. Electrically isolating carbon-dioxide bubbles, produced at the anode, increase the ohmic resistance of the cell. As the gas production rate is determined by the applied current density, anode covering can be decreased only by a faster evacuation of the gas from the inter-electrode space. Among others, the inclination and curvature of the anode bottom promotes the release of the bubbles and thus decreases the mean value of the covering. Indeed, anode, insert in the molten cryolite bath has a square shape with horizontal bottom. However, inhomogeneous anode consumption, electro-erosion, bath circulation and the inclination of the bath-metal interface modify this shape gradually during electrolysis. Anode bottoms become inclined with rounded comers. This concentrates the gas generation to the center zone of the anode. As the bubble layer cannot be observed directly because of the hostile environment and the opacity of the bath, real scale air-water systems are used to study the impact of the anode geometry on the anode covering and the bubble induced flow. However, the physical properties of such a system are different than that we can found in the real cells. A simulator using the Lagrangian description of the bubble layer has been built and presented in earlier papers. This tool was used to investigate the effect of the anode inclination on gas covering and bath velocity, for both C02-cryolite and air-water system. Results obtained for the second system were compared to experimental data .

Jan 1, 2006

By Guadalupe Sanchez, Roel Cruz, Sergio Castro, Claudia Beltrán, Isabel Lázaro

The recovery of zinc in refineries is strongly affected by the formation of zinc ferrites during the roasting of zinc concentrates. To achieve the highest zinc recovery most of these plants operate under high acidity and high temperature conditions in their leaching circuits. However, under these conditions high iron dissolution occurs. For iron control the common practice is to precipitate it as jarosite, and calcine is normally used as neutralizing agent. This practice causes a significant loss of metal values associated with the calcine, such as zinc ferrites and silver insoluble phases. These metal values are carried by the jarosite into confined waste in many plants. In order to diminish such losses, it is necessary to use a neutralizing agent that could substitute the use of calcine. An alternative neutralizing could be the basic zinc sulfate (BZnS). This work presents the results of a laboratory analysis on the required conditions for the BZnS production from process streams of a zinc refinery plant. Neutralizing behavior of BZnS was evaluated in iron precipitation as jarosite, in order to establish the feasibility of replacing the calcine and decrease the loss of zinc and other metals values during the iron removing step of the hydrometallurgical circuit of the zinc refinery under study.

Jan 1, 2014

By Jeffrey D. Eisenman

FRP is a proven material for the solvent extraction processes of copper production. There is a history of successful applications of FRP piping and equipment in hydrometallurgical processing. The performance of FRP equipment has not always been consistent, but at no fault of the material. Its non-metal attributes and behavior vary from those of more typical materials of construction, such as steel and alloys. FRP is a mainstay material in many areas of solvent extraction and electrowinning and yet not well understood by all. We will discuss the critical concerns, which are key to reliable performance of FRP systems. This paper will include discussion of key elements, which are fundamental to reliable FRP piping design and considered best practices. Essential design and construction considerations to maximize reliable service life of FRP equipment, such as thickeners and process vessels, used in copper extraction and processing, will be discussed. Additionally, we will expose potential pitfalls and share lessons learned from previous copper processing plant projects, which can aid and impact other copper processing projects to ensure best system performance and reliability. INTRODUCTION The corrosion resistant attributes of fiberglass reinforced plastics (FRP) make it an attractive and cost effective material of construction in corrosive service applications that are found in copper processing. FRP is used all over the processing plant in seawater, brine and sulfuric acid services where the corrosive nature of these services would challenge most ferrous materials and coatings. FRP is a fully customizable material to meet the specific needs of each service and process. FRP piping and equipment can be found throughout the hydrometallurgical process, in the acid plant, desalination, leaching processes, solvent extraction and electrowinning to name a few. Beyond its superior corrosion resistant characteristics, FRP can be made abrasion resistant by introducing particulate additives into the resin, such as silicon carbide and alumina oxide. Because many of these services have combustible organic elements in the flow streams with accompanying safety concerns, the linings can be made conductive with carbon fibers to dissipate static charges that might collect on the surface of the equipment otherwise. Further, FRP can be made flame retardant as well, where flammability may be of concern.

Jan 1, 2019

By J. B. Mawdsley

A LITILE north of the geographic centre of the Province of Saskatchewan, 150 miles north of the city of Prince Albert, is a narrow green-stone and sedimentary belt of pronounced structural characteristics. This belt, generally known as the Sulphide Lake belt, is about two and a half miles wide. During the past three years prospecting has uncovered numerous gold-bearing showings occurring chiefly along the centre of the belt for a distance of at least nine miles. The number of these showings, the nature of some of them, and their relationship to strong structural features, make it altogether likely that intensive work will eventually locate ore-bodies that will be of economic importance. The discovery of gold in the fall of 1938 on the south shore of Mackay lake, about five miles northwest of the Sulphide Lake gold-bearing belt, indicates that there are neighbouring zones of interest. This paper, an attempt to outline the present status of the interesting mineralized belt, is based largely on the information gained on a five-day tour of this district, made in August, 1939, on behalf of the Department of Natural Resources of the Province of Saskatchewan. The Sulphide Lake belt is named after a small lake centrally located in it. This lake and others are just north and within short portage distances of some of the long bays along the north shore of Lac La-Ronge, an irregular, island-studded lake, about twenty miles in diameter, in relatively rocky Precambrian country, just north of the Palaeozoic contact. The fur-trading post and settlement of Lac La-Ronge is on the west shore of this lake and a road, now under construction, will shortly link this community with the city of Prince Albert. In the past, the most direct route was an indifferent canoe route, in part following Montreal lake and river; more recently, the aeroplane has made this section easily accessible.

Jan 1, 1940

By A. J. Hargraves

"It is difficult to quantify comparatively the gassiness of a property. The most common index to gassiness, cubic feet of gas per ton of coal mined, is very arbitrary and does not take into account the geological setting nor the mining operation. The gassiness of a virgin coal in situ can be assessed, but no method is precise and the most accurate methods involve prolonged field and laboratory experiments. In general, gassiness increases with depth. Whereas 'gas' normally implies methane, other gases such as nitrogen, carbon dioxide, etc. may be present in seam gas also. The inflammability of methane is a problem, particularly the explosibility of a methane-air mixture; also oxygen dilution is involved in high gas concentrations and some gases are poisonous even in low concentrations. Cross measuring into a virgin seam is usually not as troublesome as development in the seam, where narrow openings may require strong ventilation to dilute gases exuding from the face and sides. Total extraction presents problems of gas from the working seam, or from adjacent seams, particularly at the return side, or of gas-laden air from the goaf streaming out or sometimes surging out intermittently, again on the return side. In pillar extraction or longwall retreating special roadways may be required to allow the side-to-side and end-to-end flushing of the goaf which is somewhat inherent in longwall advancing. Layering may occur, particularly where ventilation conditions are not brisk. Outbursts of gas from adjoining seams may be induced by sudden rupture of roof or floor in caving workings. Outbursts of coal and gas from the working seam may occur, mostly in development work, under special environmental circumstances. Gas problems may be reduced or eliminated by predrainage of gas ....:. rarely successful from the working seam - usually undertaken from adjoining seams prior to escape of gas released by caving. The ideal solution - general predrainage of gas to the surface from measures prior to mining - has yet to be accomplished. • In the planning of gassy mines it is possible to make an assessment of gas contained in the seams and to estimate what proportion will be released into the mine air, but emission of gas into mine workings is never steady and at present there is no better planning criterion than experience at the mine next door!"

Jan 1, 1973

By L. Fernandes

A two level factorial study was undertaken to investigate the relative impacts of factors affecting the kinetics of polytetrafluoroethylene, PTFE, assisted pressure oxidation of chalcopyrite. A copper flotation concentrate, principally composed of chalcopyrite, was leached in 850 mL of leach solution under conditions similar to those of the CESL process. The factors manipulated were: the amount of 1/8" PTFE beads added (100 g or 650 g), oxygen pressure (690 kPa or 1030 kPa), and concentrate addition (10 grams or 65 grams). Copper extraction data, which indicated complete leaching under certain conditions, were fit using a shrinking core model from which rate constants were estimated and further used to generate a statistical model containing only the factors of significance and their interactions. Results indicated a strong positive effect of PTFE addition and a strong negative effect of increasing pulp density. A weak negative interaction between increasing PTFE addition and pulp density was attributed to PTFE/concentrate agglomeration.

Jan 1, 2014

By J. A. Finch, A. M. Elmahdy

Blending frothers is becoming common in flotation practice apparently enhancing performance. However, there have been no studies to understand the blend mechanism. In this paper, the effect of two frother blends ofF150 (polyglycol) with MIBC or pentanol (both alcohols) on bubble size, gas holdup and froth height is reported. The blends focused on a small addition of the polyglycol to the alcohols as base frother. The tests showed that the bubble size at blend concentration below the critical coalescence concentration (CCC) of the base frother was decreased but was significantly larger above the base CCC. Froth build-up showed a strong synergistic effect.

Jan 1, 2009

By E. O. Chisholm

Synopsis The colour changes effected in a solution of dithizone by trace amounts of copper, lead, and zinc mineralization provide a sensitive field test for these metals. The method has been used with success by the United States Geological Survey to trace zinc orebodies under residual soils. The dithizone test is used here on samples of non-residual soil overlying a gold-bearing zone in which the gold is associated with disseminated sphalerite, galena, and chalco-pyrite. A gold-bearing zone was successfully traced under overburden ranging from a few inches to five feet in depth by means of this method. The method may prove useful in guiding preliminary trenching through light overburden, by outlining the extent of copper, lead, and zinc mineralization. Introduction The dithizone test affords a rapid, simple, and delicate test for the presence of zinc in soil and water and is suitable for use under field conditions. It has recently been used with success by the United States Geological Survey to outline a zinc-rich area in the residual soil over a primary zinc deposit in Tennessee. The purpose of the present study was to ascertain whether the method could be used to trace a gold-bearing zone, containing associated zinc mineralization, under shallow, non-residual, glacial overburden. The results obtained indicate that the method can be used to guide preliminary trenching in overburden up to six feet in depth. Tests made of the water near lake-shore outcrops also indicate that favourable prospecting zones may be located from the water, within five feet of the shore. It is felt that this simple field test should find a wider use in prospecting, because, under certain conditions, it can outline favourable zones and thereby reduce the amount of blind trenching necessary. The following pages describe the type of deposit tested, the method used, the .results obtained, and the difficulties encountered by a novice in the use of this chemical procedure. The author is indebted to the officials of Nor-Penn Mines, Limited, for their co-operation while the tests were being made; to the late Richard Bouska, Kenora prospector, for helpful suggestions; and to F. W. McCamus, University of Toronto undergraduate student, who ably assisted with the work.

Jan 1, 1950

By J. Kouam

Al-Si-Cu and Al-Si-Mg alloys are widely used in several applications. Although they can be produced near-net-shapes, products made of these alloys very often require some machining. The purpose of this study is to evaluate the machinability of A319 and A356 under TO and T6 conditions. The machinability was assessed using during dry drilling machining process and the machinability indexes used are the chip form, the chip breakability and the cutting forces. It is found that 319 and 356 exhibit different machinability behaviors, especially in the T6-condition in terms of forces requirements, chip breakability and chip segmentation. It is also found that both the microstructure of the workpiece materials and the machining conditions significantly affect the chip formation mechanism, and therefore, the machining parameters could be selected to promote a chip form that is easily manageable in production.

Jan 1, 2011

By J. F. Dorion

This paper presents the results of on-going investigations on the performance of support systems in Québec underground mines. The focus of these investigations is on site observations complemented by laboratory investigations. Of particular interest is deducing the corrosion rate, at selected mine sites, as determined by the installation of monitoring coupons.

May 1, 2009

By Dan Nower

Machinery Health Monitoring of Shovels MINExpo 2012: Caterpillar announced the largest Electric Rope Shovel, capable of 120 short tons The next day, JoyGlobal (P&H Mining) ?one-upped? CAT, introduced a shovel capable of 135 short tons Large Concern: breakdown (unplanned outages) of one machine will be more disruptive to production

May 1, 2013

By Nawshad Haque, Leanne Smith, Hal Aral, Joseph Cho, Warren Bruckard

"Water availability is one of the principal parameters in determining the feasibility of mining projects in arid and semi-arid regions. The volumetric water footprint (VWF) of a conceptual model of a copper flotation plant was found to be 2.45 kL/t Cu ore, compared with an actual measurement reported in the literature of 2.72 kL/t Cu ore. The flowsheet considered included mineral processing stages such as crushing, screening, grinding, classification, separation, flotation, thickening and filtration. The effect of a number of variables on the VWF was evaluated, including solid/liquid ratio, feed mass flowrate, ore loss, water loss, moisture content of ore, ore grade and water recycling. The use of seawater with recycling provided the most environmental and economic advantage among several scenarios evaluated. The study assumed a price of $1/kL freshwater, $4/kL for transport over a 200 km distance at 2,000 m altitude and $4/kL for water treatment. The water related cost of the desalinated seawater use scenario was A$493/t Cu concentrate, while the water related costs of fresh water and blended water scenarios were A$308/t and A$268/t Cu concentrate, respectively. The water related cost (fresh water scenario) accounted for 44% to 49% of the entire mining and processing costs that included drilling, blasting, loading, hauling, crushing, grinding and concentrating. The total overall cost was A$435/t Cu concentrate for the seawater with recycling, compared to A$451/t Cu concentrate for the fresh water with recycling case.INTRODUCTIONReducing the water footprint (WFP) by utilising alternative water sources has been a focus of mining projects due to increasing concerns about water scarcity and growing energy costs. The global mining industry can expect to experience fresh water shortages in the future, and saline or hyper-saline water may be the only available water source to process minerals in arid regions. Extensive studies on alternative water sources (e.g. seawater, desalinated seawater, blended water) and the reuse of process water have recently been conducted (Moreno, Aral, Cuevas, Monardes, Adaro, Norgate & Bruckard, 2011; Aral, Mead, Cuevas, Davey & Bruckard, 2010). Such studies provide sustainable and economic strategies for mines and concentrators in the arid or semi-arid regions of the world such as in Chile, Peru, Indonesia, and Portugal. More work, however, is needed to confirm water consumption data for different base metal flowsheets and use this data to develop water models that can lead to reduced WFPs and more sustainable water usage in the mining industry."

Jan 1, 2016

By G. W. H. Norman

The surficial Archæan rocks of the southern gold belt of western Quebec are constricted near Kewagama lake by granite masses to the north and south. This divides the belt into natural eastern and western parts. This paper deals with the eastern part, extending from Malanie to Haig township. In this section the Keewatin-Timiskaming rocks have a length of about 70 miles and end abruptly against garnetiferous gneisses of the Grenville terrain. In the western half of the section where exploration has been under way since the early twenties, there are sixteen mines that are or have been in operation, and eleven prospective mines. In the eastern half where exploration has been carried on since the early thirties, six prospective gold mines are under development, one· of which, Louvicourt Goldfields, is at the initial production stage. Of the sixteen properties in the western half that are operating or have operated, all, except the Golden Manitou, which is a base metal mine, and the old Green Stabell from which there was a small production of copper, produce gold. Of the eleven prospective mines in the western half nine have gold. New Bidlamaque has gold and copper and one, East Sullivan, has copper-zinc ore. Since production began in 1927 gold, silver, zinc, copper, and lead having a total value of about $10,000,000 have been produced from the mines of the eastern section of the southern gold belt of western Quebec.

Jan 1, 1954

By K. M. Wild, C. D. Martin, F. Amann

Peak laboratory strength data obtained from low permeability clay shales/rocks often display a bilinear or non-linear failure envelope. In many of these tests pore pressures are not measured because of issues associated with back-saturation prior to confined compressive loading. In such tests the effective state of stress at failure remains unknown and provides room for speculation. The non-linear shape of the failure envelope may have several reasons including the influence of capillary forces or the tendency of a saturated clay shale to dilate as the confining stress is changed. The former stems from sample preservation, preparation or core unloading effects and represents a partly saturated state (i.e., not representative for the in-situ state); the latter represents the response of a saturated material. This contribution discusses these issues based on a data set obtained from Opalinus Clay specimens, and concludes that without a careful back-saturation processes knowledge of the underpinning reasons for the non-linear failure envelope cannot be obtained.

Jan 1, 2015

By C. J. Li, J. L. Feng

In the present study we focuses on developing the poroelasticity model that deals with adsorptioninduced permeability change mostly occurred in porous media constituted several phases such as coal. The underlying pressure induced by adsorption is obtained by Virial expansion form, which is substantially founded on statistical physics. The corresponding thermodynamic pressure applying on the pore surface is then used to detail the pore pressure and further to evaluate the macroscopic volumetric strain and the porosity. In the process of physical adsorption, the adsorbed phase is in thermodynamic equilibrium with the gas phase regardless of pore size, and the corresponding chemical potentials are all equal. The relationship between surface strain and volumetric strain is derived under infinitesimal deformation conditions to gain an explicit formulation of pore surface area with respect to volumetric strain and porosity. After the formulation of surface stress modified by the Langmuir isothermal adsorption is derived, the differential micromechanical constitutive equations of porous media are obtained. By supposing that the ratio of current permeability to initial is equal to the cubic ratio of current porosity to initial porosity, the differential equations for permeability change is consequently derived. The numerical simulations by the present model for permeability change of coal induced by adsorption of CO2 and CH4, respectively, are presented under confined stress conditions. The predictions from the model are good in agreement with the experimental data of sorption-induced permeability change of coals in the literature.

Jan 1, 2015