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By T Kilpatrick

Managing heat stress on Australian mine sites is a complex and enduring challenge due to the combined and variable contribution of environmental conditions, physical activities, and protective equipment. Inappropriately managed, heat stress can place significant physical strain on workers, leading to serious and chronic health issues. Additionally, excessive heat stress can dramatically reduce productivity, with 30 per cent of workers reporting a loss of productivity due to occupational heat strain. In Australia, due to increased absenteeism and reduced work performance, heat strain is estimated to have an annual economic burden of over $8 billion.

May 5, 2022

By T. E. Leontis

The specific effect of various rare-earth metals on the room- and elevated-temperature properties of magnesium has been evaluated. Alloys containing didymium exhibit the highest tensile and compressive strengths at room and elevated temperatures. All the rare-earth metals increase the creep resistance of extruded magnesium at temperatures in the range of 400° to 600°F, but the degree of enhancement depends on the temperature and on the concentration of the added metal. THE effects of rare-earth metals on the properties of sand-cast magnesium were discussed in some detail in earlier paper by the author.' The present paper deals with the effect of the same alloying elements on the properties of extruded magnesium. This investigation also had as its aim the development of a wrought alloy having a better combination of room-temperature strength and ductility and elevated-temperature strength and creep resistance than is found in magnesium-Mischmetal-manganese alloys, which have been reported earlier.2-5 The only known attempt to study wrought magnesium alloys containing pure cerium instead of Mischmetal was made by Mellor and Ridley.6 They found that in the form of rolled bars there is a definite, optimum cerium content for creep resistance at 200 °C and that the creep resistance of these alloys at 200 °C is significantly Improved by heat treatment at 550" to 580"C. In the present investigation the compositional variation in mechanical properties of the following alloy systems is presented: I—magnesium-Misch-metal. 2—magnesium-cerium-free Mischmetal. 3— magnesium-didymium. 4—magnesium-cerium. 5— magnesium-lanthanum. Alloys containing predominately praseodymium are not included in this series because of the lack of this material. Experimental Procedures The alloying ingredients used in preparing the alloys described herein are the same as those reported in the earlier paper.' Cerium-free Mischmetal is the rare-earth mixture remaining when the cerium is removed from Mischmetal, which contains all the rare-earth metals as they occur naturally in mon-azite sand, the ore from which Mischmetal is produced. Removal of both cerium and lanthanum from Mischmetal leaves what is commonly called "didym-ium," consisting predominantly of neodymium and praseodymium. Although the composition of the particular batch of each metal used may differ somewhat from the analysis presented previously, these differences are not great enough to warrant repeat- ing the specific composition of each material. The electrolytic magnesium used as the starting material in these alloys has the same typical analysis as that given in the earlier paper.' The alloys were prepared in small laboratory melts applying all the necessary precautions for alloying rare-earth metals with magnesium described by Marande.' Most melts were large enough to cast one 3 in. diam billet 10 in. long. In a few cases, particularly the didymium-containing alloys, the lack of sufficient amounts of the rare-earth metal limited the size of the billet to 6 to 8 in. All billets were scalped to a diameter of 2 15/16 in. and faced to a length of 9 ¼ in. as limited by the size of the extrusion container. The alloys were extruded into ½ in. diam rod on a 500-ton direct-extrusion press using a 3 in. container. The details of the extrusion step are: billet preheat, 925°F (2 hr); container temperature, 900°F; die temperature, 900°F; extrusion speed, 10 ft per min; reduction ratio, 36:1; and percent reduction, 97.3. The lower melting point of alloys containing didymium' necessitated reduction of the extrusion speed to 5 ft per min in order to prevent hot shorting during extrusion. Adequate lengths were cropped from both ends of each extruded rod to assure that all the material used for tests was extruded under uniform conditions. Tensile and compressive properties at room temperature are reported in the several conditions of heat treatment. The ASTM designations are used to distinguish these conditions as follows: T5—Direct age at 400°F (16 hr) T4—Heat treat at 950°F (4 hr) for alloys containing didymium T4—Heat treat at 1050°F (4 hr) for all other alloys T6—T4 + age at 400 °F (16 hr) The lower heat-treating temperature for alloys containing didymium is necessitated by the lower melting point of these alloys. All heat treatments were conducted in electrically heated, circulating-air furnaces. A protective atmosphere containing 0.5 to 1.0 pct sulphur dioxide was used for the high temperature heat treatments. Tension and creep specimens 6 Yz in. long and compression specimens 1½ in. long were cut from the extruded rod. A reduced section of ? in. diam was machined on the tension specimens, whereas on the creep specimens a reduced section of 0.450 in. diam

Jan 1, 1952

By Fei Dai

Musculoskeletal disorders (MSDs) are a group of painful disorders that affect muscles, tendons, nerves, joints, cartilage, and ligaments. They are a serious problem among the workforce in the United States. In the construction industry, high physically demanding tasks expose construction workers to a number of well recognized MSDs risk factors such as repetitive motion, high force exertion, and awkward body posture. Finding ways to effectively identify and evaluate risks of MSDs can significantly alleviate this problem. To this end, this paper reviews state of practice and research in the assessment of risks of MSDs among construction workers, in which a number of biomechanical models have been developed to evaluate joint and tissue loading with the aid of state-of-the-art remote sensing technologies. Findings from the review reveal that despite the advances in tracking human motion and muscle activities, current remote sensing approaches still involve sophisticated instrumentation and expensive experiment setup. These factors greatly limited the applicability of such approaches in real construction settings. How can we detect and evaluate the construction worker?s MSDs risk in real work environments? In this paper, strategies by utilizing video surveillance systems are presented, to set the stage for addressing the above question and discussing future research in real-time, marker-less, and costeffective MSDs risk assessment.

Aug 1, 2013

By A. A. Remes

High precision on-line particle size distribution measurement of mineral slurries has recently be-come available. It provides new tools for the development of monitoring and optimization methods for mineral grinding and separation circuits. The paper presents the development work at the Kemi chromite concentrator plant of Outokumpu Tornio Works in Northern Finland. The Kemi concentrator processes annually 1.2 Mt of chromium ore. The products are upgraded lumpy ore and metallurgical grade concentrate. The concentrate is produced using gravity separation methods, preceded by a rod mill - ball mill grinding stage. The separation process performance is strongly dependent on the particle size distribution of the grinding product at the Kemi plant. Particle size distribution has a significant effect on the concentrate grade and recovery. Currently a new laser diffraction based on-line particle size analyser is used for monitoring the grinding product. The analyser system allows the measurement of the whole cumulative particle size distribution simultaneously. It provides a wealth of new measurement information for process control. A monitoring and optimization scheme for grinding and gravity separation based on the particle size information is presented. The goal is to minimize the production of fine slime, and subsequently to improve the concentrate quality and minimize chromite recovery losses. Data-based recursively identified linear PLS process models are developed for optimization purposes. The preliminary results of the monitoring system operation in on-line use are presented.

Jan 1, 2014

By Olav K1omstad1ien

The lean, but extensive iron ore deposits of the Dunderland Valley north of Mo i Rana, Norway, is the raw material for the Rana Mines which is a division of the state owned steel mill A/S Norsk Jernverk. Activities for the exploitation of the orebodies were commenced in 1902 by the English Dunderland Iron Ore Company. During its operating period the company constructed a total of two large scale concentrating plants. The activities were strongly marked by technical problems and labor disputes. Thus actual production was limited to the years 1904-1908, 1928-1931 and 1937-1939. During these periods a total of 1.9 million tons of crude ore was mined and 0.6 million tons of concentrates produced for export. The present plant commenced operations in late fall of 1964. Up to and including 1976 about 26.6 million tons of crude have been put through the concentrating plant and about 10.7 million tons of concentrate produced.

Jan 1, 1978

By H. Russell, N. DePriest, J. D. Quaranta

Valley-fill structures built of blasted rock overburden from Appalachian mountaintop surface mines pose many reclamation challenges. The steep mountainous terrain, short valley lengths, and straight stream channel profiles create significant challenges to implementing fluvial geomorphic landform design in terms of both form and function, and from a safety and constructability perspective. The fluvial geomorphic landform design approach balances erosive and resistive forces by considering long-term climatic conditions, soil types, slope profiles and vegetation types. Commercial geomorphic landform design software tools do not specifically analyze the stability and factor of safety for the computer-designed landform slopes. This research investigated slope stability parameters and factors of safety between a traditional valley-fill design with a geomorphic landform alternative. Slope stability assessments were performed on two profile geometries. Finite-element modeling of a permitted valley-fill and a geomorphic design alternative indicated that slope angle and internal angles of friction associated with the gradation of the overburden greatly affected the designed factor of safety for both designs. The geomorphic designed slopes yielded the highest factors of safety out of 14 models analyzed with all cases having factors of safety over 2.0. The high factors of safety are attributed to shallow slopes and beneficial surface and internal drainage.

Jan 1, 2014

By A Coelho, D Bruce, H Grosser, C Parken, M Xia

Carrapateena is a new underground sublevel cave mine and was officially opened in 2020. It has a mine life of 20 years. Development began in 2016, and with the rare opportunity to start a with a blank canvas and having a long mine life, an effort was made to explore how to incorporate innovative and leading-edge technologies. The Ventilation on Demand (VoD) system was designed with the objective to optimise power consumption and ventilation delivery through the primary and secondary ventilation systems. Primary fans controlled by Variable Speed Drives (VSDs) and dualwinding secondary fans with multiple setpoints control the delivery of overall quantity. Automated butterfly dampeners control the regulation of air to individual production crosscuts, and automated louvres control the exhaust quantities from the mining levels. Ultra-sonic flow sensors are installed to measure air quantity and environmental stations are installed to measure air quality. Both are designed to play a key role in control and calibration of the system. It was quickly identified that no one vendor could provide a holistic solution to meet the design requirements. A strategy was derived to use multiple vendors, harnessing the specific strengths of each. A control system has been developed to allow the Site Operations Control Centre (SOCC) to oversee and control real-time delivery of ventilation as required by operations. The first full level installation of the VoD system was completed in September 2020.

Mar 15, 2021

SYMPOSIUM ON THE RECOVERY OF PYRITE The proceedings of the Symposium on the Recovery of Pyrite, held in Johannesburg in June 1969, may be ordered from the Secretary, S.A.I.M.M., P.O. Box 61019, Marshalltown, Transvaal, at the reduced price of R5.00. Papers and addresses presented at the Symposium were: Opening Address by Mr J. K. E. Douglas (President). "The world sulphur position," by W. C. J. van Rensburg (Member). "The South African sulphur position," by D. L. Taylor (Member). "The recovery of pyrite at Government Gold Mining Areas Limited," by R. J. Westwood (Member), G. S. Stander (Affiliate) and H. P. Carlisle (Member). "Recovery of pyrite concentrates from colliery-waste discards-A preliminary assessment," by W. A. Gilbert (Visitor) and E. A. Nugent (Member). "The role of pyrite in upgrading the uranium content of Witwatersrand conglomerate ores by means of the heavy-medium separation process," by D. J. Tutt (Associate Member). "Pyrite recovery by jigs at Durban Roodepoort Deep Limited," by E. J. Dominy (Affiliate), F. Diamond (Affiliate) and A. D. Graham (Affiliate). "The storage of pyrite concentrates," by Joan C. Campkin (Visitor) and P. J. Lloyd (Member). "The flotation plants of the Anglo-Transvaal Group," by L. A. Bushell (Member). "Pyrite flotation with amines and cyanidation of the products," by E. H. D. Carman (Member). "Gold recovery by cyanidation from mill products obtained after pyrite flotation," by P. G. Mrkusic (Graduate), M. Sciarone (Visitor) and H. E. Simonsen (Visitor). "The influence of sulphydryl and cationic flotation reagents on cyanidation of native gold," by K. G. Ashurst (Visitor) and W. P. Finkelstein (Member). "Laboratory tests on the flotation of pyrite from Witwatersrand gold ores by cationic collector," by J. Levin (Member), and M. L. Veitch (Visitor). Closing Address, by Dr R. E. Robinson (Director, National Institute for Metallurgy). INCOME TAX: POST-GRADUATE STUDY COURSE CONCESSION As a result of representations made by the Associated Scientific and Technical Societies of S.A. and the Suid-Afrikaanse Akademie vir Wetenskap en Kuns, engineers and scientists will now be allowed to deduct expenses incurred on post-graduate study courses from their taxable income. The conditions of this concession are set out in section 16 of the Income Tax Act, 1969, which reads as follows: 16. (1) The following section is hereby substituted for section 16 of the principal Act: 16. "Notwithstanding the provisions of section 23(a) and (b), there shall be allowed to be deducted from the income of any person who is a dentist or medical practitioner or practises any profession referred to in paragraph (a), so much as the Secretary may allow of any expenditure incurred by such person in the circumstances contemplated in paragraph (c), if the Dental Association of South Africa in the case of a dentist, or the Medical Association of South Africa in the case of a medical practitioner, or the "Suid-Afrikaanse Akademie vir Wetenskap en Kuns" or the Associated Scientific and Technical Societies of South Africa in any other case, certifies in such form as the Secretary may prescribe that such person- (a) if he is not a dentist or medical practitioner, is the holder of a degree in engineering or allied technology or natural sciences awarded by a recognized university on completion of a prescribed minimum period of study of not less than four academic years or the equivalent thereof and enabling the holder thereof to practise the profession of an engineer or a profession for which advanced and specialised scientific knowledge is required which relates directly to- (i) the development or exploitation of natural resources; (ii) mining or prospecting for minerals; (iii) the production of pastoral, agricultural or forest produce ; (iv) the breeding or care of farm animals; (v) any industrial process; or (vi) the training of specialists in any branch of science or technology connected with any aforementioned profession; (b) has practised his profession for not less than three years; and (c) has incurred such expenditure during the year of assessment in respect of the attendance by him of any postgraduate study course approved by such body to improve his qualifications for carrying on his profession in the Republic". (2) The amendments effected by subsection (1) shall first take effect in respect of assessments for the year of assessment ending on the twenty-eighth day of February, 1970. From this section it is clear that the concession will only be granted if the application is accompanied by a certificate, which certificate must be either signed by the Chairman of Die Akademie or the President of the Associated Societies. In terms of the authority granted such certificates must certify that: (i) the taxpayer concerned has practised his profession for not less than three years; (ii) the expenditure was incurred by the taxpayer during the year of assessment indicated in the certificate; (iii) the expenditure was incurred by the taxpayer in respect of the attendance by him of a post-graduate study course approved by the Associated Scientific and Technical Societies of South Africa or Die Suid-Afrikaanse Akademie vir Wetenskap en Kuns, as the case may be, to improve his qualifications for carrying on his profession in South Africa; (iv) the taxpayer is the holder of a degree in engineering or allied technology or natural sciences, which degree was awarded by a recognized university,

By Rustu S. Kalyoncu

Nonoxide ceramics with improved high-temperature properties could substitute for high-temperature alloys and reduce toe Nation's dependence on imports of Cr, Co, Ni, and Mn. To meet this objective, the Bureau of Mines conducted research to synthesize u1trafine reactive boron nitride (BN) powders BN powders were prepared at temperatures ranging from -75? to 750? C. Low-temperature reactions (-75? to 200? C) between boron halides and N compounds led to formation of e1emento-organic compounds that were thermally decomposed to u1trafine (approximately 100-to 150-A particle size) reactive BN powders. BN powders were also prepared through the reaction of a 10w-me1tinginorganic B compound (boric acid, borax) with an organic N compound (carbimide and thiocarbimide) in N2 and/or ammonia (NH3) atmospheres at temperatures between 500? and 750? C.

Jan 1, 1986

By R E. McIvor, K M. Bartholomew

Classification system efficiency (CSE) is a simple, powerful metric that provides a comprehensive measure of classification system performance. CSE directly quantifies the amount of coarse solids in the mill, and as a result, also directly quantifies the percentage of mill power being used effectively. In this manner, it is an effective, practical grinding energy efficiency metric.Three independent variables drive CSE: circulating load ratio, sharpness of classification, and classifier bypass. Due to practical downstream constrains on per cent solids, improvements realised by increasing circulating load reach diminishing returns as sharpness of classification and bypass deteriorate in the most commonly used classification device, the hydrocyclone. This combination of effects leads to the use of CSE, and its relationship to operational economics, as an objective circuit optimisation criterion.Its simplicity in measurement makes CSE a useful tool for the plant metallurgist, and it is not subject to a great amount of experimental error. CSE provides the plant operator a fast, simple, and effective means to evaluate the performance of the plant classification system. Improvements in CSE relate directly to circuit throughput and energy efficiency. This paper, through description and plant case studies demonstrates the power and utility of this emerging grinding system optimisation metric.CITATION:Bartholomew, K M and McIvor, R E, 2013. Classification system efficiency - a comprehensive closed-circuit grinding optimisation metric, in Proceedings World Gold 2013 , pp 389-394 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By Ballard H. Clemmons

THE future of the steelmaking industry of the Birmingham, Ala., district is closely related to and, in a large measure, dependent on the development of workable, economic processes of ore concentration. Operations thus far in the area have been possible only because of the fortuitous occurrence of iron ore, fluxing stone, and coking coal-all the primary iron-making materials- within a 25-mile radius of the blast furnaces. Commercial ore of the district consists mainly of a 10 to 20-ft hematite-calcite-silica bed locally known as the "Big Seam," a component of the Clinton formation of Silurian Age. At present mining rates, this ore will be available for a number of years. It is largely mined under 1000 to 2000 ft of cover and transported on 15 to 20" slopes that, in some instances, are as much as 10,000 ft long. Under these conditions, particularly with increasing distances from face to portal, mining costs are gradually becoming disproportionately high. Although not a major factor thus far, it should also be noted that the average annual ore output of the district is gradually be- coming more siliceous.

Jan 1, 1950

By M. Massinaei

Recently constructed circuits have included multiple stages of columns in a variety of applications, from roughing to cleaning. The Miduk copper concentrator (in south-eastern Iran) is one of the unique mineral processing plants which use column flotation cells as rougher. As the bulk of final concentrate is produced by rougher columns, optimized metallurgical performance of these cells is crucial. This paper will present the study and optimization of, a froth washing system of columns. For this purpose, the cross-sectional area of orifices was increased and their orientation altered. Concentrate assay for copper and silica, in addition to bias rate were found to be the assessment criteria. Modification of the wash water system resulted in increasing the purity of rougher and final concentrate. Negative bias and short-circuiting of wash water into the concentrate launder were the main causes of improper froth zone washing in the former system.

Jan 1, 2007

By Felipe P. D. Lopes, Caroline G. de Oliveira, Sergio N. Monteiro, Lucas A. Pontes, Janine F. de Deus

For decades, natural fibers have been studied as an economical and environmentally viable alternative to use instead of some types of synthetic fibers, for example fiberglass. To find the best way to make composites, the investigations shall be under various configurations, which is extremely important to understand the potentialities and facilities. To aim the comparison of impact performance of epoxy matrix composites reinforced with ramie fabric, the composites were produced by two different methodologies: under pressure and vacuum. The results show that the composites produced under pressure have greater resistance to both the Charpy and Izod Impact than under vacuum conditions.

Mar 1, 2018

By C. E. White

History The Con-Rycon mine is situated in the Yellowknife mining district, North West Territories, 608 air miles north of Edmonton, Alberta. The earliest reported discovery of gold in the area was made in 1898 but no extensive exploration occurred until 1928. The birth of Yellowknife as a mining community took place in 1934 with the staking of the Rich group and subsequent shipping of 16 tons of high grade ore. The Giant group was also among the claims staked in 1934, and later staking showed a tendency to close the gap between these two properties. In the fall of 1935, the A.Y.E. claims, situated south of the Giant group, were staked to cover a discovery of the Geological Survey of Canada and, after general release of the Survey's information, the adjoining ground was staked. These claims included the Con, Negus, Meg, and Kam groups. In 1936 four lapsed claims were re-staked as the P and G group and later acquired by Rycon Mines, Limited, controlled by the Consolidated Mining and Smelting Company of Canada, Limited. The Con and various adjacent groups owned by Cominco are now operated with the Rycon under one management. Surface trenching on the Con property started in 1936 and, during the fall and winter of 1936-37, a 60- foot 5 ft. by 9 ft. inclined prospect shaft was sunk. The encouragement provided by the shaft and diamond drilling in 1937 led to the decision to establish a mining plant, and in August, 1938, the 100-ton cyanide mill produced its first brick- the first gold brick poured in the history of the North West Territories. In November, 1938, the mill was enlarged to a 175-ton capacity and operated at this rate until 1941, when refractory ore was encountered. This situation was met by the installation of flotation and roasting units and, at the same time, the milling capacity was increased to 300 tons daily. Labour shortages and Government restrictions forced a reduction of output and in 1943 milling was suspended while mine development continued on a reduced scale throughout the war years. The present full-scale of operations was resumed in 1946 and the total production to the end of 1948 amounted to 288,853 oz. gold and 72,347 oz. silver.

Jan 1, 1949

By AIME AIME

ARRANGEMENTS for the Annual Meeting of the Institute were well advanced at the end of December as the following program will show. Heretofore this has been printed separately, but its inclusion in the Annual Review issue of MINING AND METALLURGY will, it is hoped, make it more easily available for reference until the final program is issued, which will be distributed at the meeting. Added details will appear in the February issue. Last year's meeting drew a record crowd of over 2300 which should be exceeded this year. Early reservations at the headquarters hotel, the Waldorf-Astoria, or any other convenient hotel are desirable, as are prompt reservations for the Annual Dinner. No one need worry about too much speechmaking this year, for the honors will be awarded and accepted in a few words instead of a few paragraphs, in seconds rather than minutes.

Jan 1, 1939

By Yinan Zhang, Y. Luo

Most of the reported coal spontaneous combustion events occur in surface and underground mines where low rank coals (i.e., subbituminous and lower for this particular studies) are extracted indicating their high propensities for spontaneous combustion. Low rank coals have high moisture content (15 to 45%) and are capable of absorbing more moisture in dried condition. However, it is hard to induce the initial stage of self-heating process for the low rank coal using the current laboratory R70 testing method — a method widely used in the coal industry. Like a sponge, dry low rank coals can absorb water vapor in the air while the heat contained in the moist air is transferred to coal and served as the required activation energy to initiate the coal self-heating process. In order to prove this theorem and quantify the effects, the R70 adiabatic oxidation testing method has been improved to introduce a controlled moist flow into the coal reaction vessel. Tests using the new method and its setup on low rank coals showed that the initial self-heating process of coal sample can be greatly accelerated by the added water vapor — impossible with the regular R70 method. Once the self-heating is sustained, the removal of air moisture can further accelerate the process.

Sep 17, 2021

Jan 1, 1998

By M Carr, C Wheeler, M Lurie, B Chen

The demand for steel products in modern society is prompting the iron ore industry to optimise their operations to ensure sustainability of fines and lump products. One of the key components in the iron ore transportation chain are belt conveyors. The energy consumption of modern belt conveyor systems has reduced considerably over the past few decades, however, there is still significant scope for further reductions, especially when heavily loaded long overland belt conveyors are considered. A new rail based continuous bulk material transportation system has been developed by researchers at the University of Newcastle to reduce the energy consumption of heavily loaded and long overland conveyors. The Rail-Running Belt Conveyor technology is a state-of-the-art continuous belt conveying technology which provides an innovative and novel departure from conventional continuous bulk material transportation systems with significant energy and economic benefits. This paper presents an overview of a Rail-Running Belt Conveyor variant which considers an enclosed belt. Enclosed belt conveying has the benefits of encapsulating the bulk material, and thereby reducing dust emissions and moisture ingress, in addition to being able to negotiate smaller radius horizontal and vertical curves leading to greater flexibility. To quantify the primary differences between conventional conveying technologies, the Denver office of thyssenkrupp Industrial Solutions (USA) developed a case study for an 11 km long conveyor. The conveyor design throughput was 2750 t/h and included a small net elevation loss of 10 m. When considering CAPEX the Rail-Running Pipe Conveyor equipment supply cost is approximately 45 per cent of the cost of a conventional pipe conveyor, while savings upwards of US$50M emerge for CAPEX combined with five years of OPEX. The savings vary with the topography and density of the bulk commodity, with iron ore generally showing increased savings because the high bulk density increases rubber losses in conventional conveyors.

Nov 8, 2021

Jan 1, 2003

By Cristina Muñoz Fernández, Sonia Balcázar

Los mecanismos operacionales de atención de quejas y reclamos a nivel de mina (MQR) son procesos formales que las empresas ponen a disposición para permitir a personas o grupos plantear inquietudes y buscar la remediación y reparación de los impactos reales o percibidos de sus actividades. Con el objetivo de impulsar el desarrollo y fortalecimiento de los MQR del sector minero en la región andina, entre agosto del 2021 y enero del 2022, la Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) financió un estudio de análisis y comparación de los mecanismos operacionales de atención a reclamos en la minería en Bolivia, Ecuador, Chile, Colombia y Perú, que sirve como base del presente trabajo técnico.

Sep 30, 2022