. A model denominated Consumption Habit Exposure Model, CHEM , was developed for the calculation ... more . A model denominated Consumption Habit Exposure Model, CHEM , was developed for the calculation of human individual acute and chronic exposure to copper in drinking water. The model can estimate daily exposure of individuals as well as the maximum concentration of copper which individuals ingest during a 24-h period. The CHEM model requires carrying out a water consumption habit questionnaire and measuring the minimum and maximum concentration of copper in homes, as well as minimum and random copper concentration at work and study places. The case study employed was a representative sample of the population of Santiago, Chile. The validation of the model was established with reference to the application in a limited number of homes of the Ž . composite proportional method, CPS , used to measure human chronic ingestion of contaminants from drinking water. It was found that 4.5% of the sampled population is exposed daily to one cup of water or more at the maximum copper concentration available at the tap. The probabilities that the different age groups are exposed to one cup or more of water at c during 1 day are greater for the 20᎐64-year-old group, followed by the 64-year-old MAX group, and then by the younger age groups in descending order. Ingestion of copper from drinking water by the population of Santiago is on average 9.0% of the World Health Organization recommendations for minimum total ingestion of copper for adults, assuming that 100% of the copper contained in drinking water is absorbed.
International Biodeterioration & Biodegradation, Mar 1, 2008
... The decrease of pH at the interface copper/solution is the main factor controlling MIC of cop... more ... The decrease of pH at the interface copper/solution is the main factor controlling MIC of copper (Webster et al., 2000). ... (Webster et al., 1996); Acidovorax delafieldii, Cytophaga johnsonae, and Micrococcus kristinae (Critchley and Fallowfield, 2001); Acidovorax sp. ...
Journal Of Environmental Science And Health, Part A, Nov 1, 2006
Daily exposures to chemicals in drinking water are of importance in risk assessment to human heal... more Daily exposures to chemicals in drinking water are of importance in risk assessment to human health. However, exposure assessment of chemicals in drinking water has seldom been performed in China. Until now, no such a detailed exposure assessment was reported in China. The aim of the present paper is to describe the scenes of daily exposure to Cu and Zn in drinking water by the population of Shanghai, China in the summer of 2003. A total of 163 volunteers and/or homes were selected to be statistically representative of the population of Shanghai, China. The Modified Consumption Habit Exposure Model (CHEM) method combined with the measurement of metals concentrations in stagnant water and actual ingested water was used to describe the daily exposure. The Consumption Habit Exposure Model method results showed that water consumption ranged from 1.7 to 2.2 L/day, varied with different age, gender and work location groups. Chemical results showed that the average Cu and Zn concentrations in stagnant water were much higher than those in actual ingested water (13.5 microg/L and 1.55 mg/L vs. 10.8 microg/L and 0.29 mg/L). Exposure assessment results also showed that volunteers had the highest exposure from the time of after breakfast to before dinner, and had the lowest exposure during the 15 minutes before sleeping. It was also showed that there were few volunteers directly exposed to stagnant water, although six hours stagnant time can be reached in most of the homes in Shanghai in the morning. The mean daily exposures to Cu and Zn were 0.36 microg/kg/day and 0.01 mg/kg/day. Daily intakes of Cu and Zn from drinking water by Shanghai people were 1.8% and 4.4% of the World Health Organization recommendations for minimum total intakes of Cu and Zn for adults, respectively.
... This focus typically recognizes and rewards mineral exploration results only if they positive... more ... This focus typically recognizes and rewards mineral exploration results only if they positively affect a company's cash flow portfolio (existing mines and ... short-run fluctuations, real copper prices show little long-run trend, neither rising nor falling greatly (Svedberg and Tilton, 2006 ...
Water Science & Technology: Water Supply, Dec 1, 2010
The presence of natural organic matter (NOM) in drinking water can increase the levels of copper ... more The presence of natural organic matter (NOM) in drinking water can increase the levels of copper released from copper pipes to water and inhibit the formation of protective deposits such as malachite. Since adsorption of NO M on copper pipes surfaces is believed to be one of mechanisms that explains this phenomenom, the objective of this study was to determine kinetics and the adsorption equilibrium of main components of NOM, humic acid (HA) and fulvic acid (FA), onto copper surfaces. The kinetics and equilibrium adsorption of HA and FA on copper foils were examined using batch experiments at 22°C. HA and FA followed pseudo second-order kinetics adsorption. Rate constants measured were 2.59 x 10 -1 (mgTOC cm -2 h -1 ) for HA and 3.13 x 10 -1 (mgTOC cm -2 h -1 ) for FA. The adsorption behavior of HA and FA on the copper surface is in accordance with the Langmuir adsorption isotherm. Langmuir adsorption constants measured were 5.98 x 10 -2 L mg -1 for HA and 4 .78 x 10 -2 L mg -1 for FA. The copper foils exposed during five months to FA formed malachite deposits, whereas those exposed to H A did not and just cuprite was found. The results of this study showed that both HA as well as FA adsorption on copper surfaces is favored and no significant differences were found in the adsorption parameters calculated for both compounds. However, the inhibition of the malachite precipitation could be attributed to the HA adsorption.
Abstract Several studies dealt in the past decades with future predictions of the copper demand, ... more Abstract Several studies dealt in the past decades with future predictions of the copper demand, motivated mainly by potential copper shortages that could arise due to insufficient reserves. It is known that there was never a shortage of reserves in order to satisfy demand in the last century and up to the present time. This paper addresses two questions. Did these concerns arise due to excessive demand forecasts, or due to stagnating reserves assumption, or due to both aspects? The article evaluates some of these predictions of future copper demand and compares forecasts with the real metal demand that materialized in past years. Also, it analyses the reserve assumptions of several studies and compares them with what really happened with copper reserves. In the case of recent forecast models that span into future years, whose copper demand is not known yet, a backcasting method was used in order to estimate forecasts, which consists of applying the model in the past. Five out of the seven models rerun in the original periods overestimated demand and two out of them considered that reserves were a fixed stock. Also, the two models studied by the backcasting method considered that reserves were a fixed stock. The four models that considered reserves as a fixed stock run out of reserves, irrespective of whether they overestimated or underestimated demand. These results suggest that predictions of a future scarcity of copper could be mainly attributed to the assumption of a fixed stock of reserves and not necessarily to overestimations of demand. The remaining five models did not consider the future availability of copper.
ABSTRACT Modelling and prediction of the copper concentration released from copper plumbing tubes... more ABSTRACT Modelling and prediction of the copper concentration released from copper plumbing tubes due to corrosion, dissolution, precipitation and other processes has not previously been successful. The model presented here is based on a set of dissolution and precipitation reactions, equilibrium between species in solution and solids, mass balance, kinetic expressions, adsorption isotherms, and surface area coverage by precipitates.The model developed has created two major outputs: first; it is the most conclusive collection of mechanistic considerations to date; and second; reasonable correlations between the model and actual data have been obtained for a broad range of waters.
Daily intakes of metals in drinking water are of extreme importance in risk assessment to human h... more Daily intakes of metals in drinking water are of extreme importance in risk assessment to human health. Some papers focused on this topic, but most of them did not consider the effect of age, gender and work location on daily intakes of metals in drinking water. The objective of present paper is to estimate the levels of Cu, Zn and As ingestion in drinking water in Shanghai, China and the effect of age, gender and work location on daily intakes of these metals. It was also the first time that such a detailed investigation on daily intakes of metals in drinking water was carried out in China in recent years. Drink/Sample (D/S) method was used to estimate the daily intakes of Cu, Zn and As in drinking water. The mean concentrations of Cu, Zn and As in drinking water were 10.8 Ag/l, 0.29 mg/l and 0.91 Ag/l, which were lower than U.S. EPA's Drinking Water Equivalent Level (DWEL) and WHO guideline values. The average daily intakes of Cu, Zn and As in drinking water was 21.12 Ag/d, 0.65 mg/d, and 1.83 Ag/d, which were on average 0.01%, 1.1% and 1.5% of the provisional maximum tolerable daily intake (PMTDI) set by the Joint FAO/ WHO Expert Committee. There was a significant difference in daily intake of Zn for different work locations ( P = 0.04). But no other significant differences in daily intakes of metals in drinking water were found according to age, gender and work location.
This paper discusses the mining development policies in Chile in the period 1974-96. This period ... more This paper discusses the mining development policies in Chile in the period 1974-96. This period includes the military government that took over the country from socialist President Allende in 1973, and the return to democracy with the election of President Aylwin in 1989 and of President Frei in 1993. The paper analyses the economic and mining policies of the military and democratic periods, and then the country's mining investment, production and exports under the prism of the main institutional development policies pursued. The analysis focuses on copper mining, where investment and growth have created a mining boom unprecedented worldwide in this century since the discovery of the flotation process in the early 1900s. Thus it is of special relevance to examine the set of circumstances that has made this boom possible. The main discussion during this period regards the legitimacy of foreign investment in mining vs the capacity and potential of the state-owned company Codelco to be a protagonist of mining development. While the more liberal sectors of the political spectrum have supported the privatization of Codelco, the more conservative sectors support the continued ownership of Codelco by the state. This discussion will be of no great consequence if the mining boom continues. Nevertheless aspects of the discussion in 1996 questioned the economic development model employed by the country since 1974. Crucial for the legitimacy of foreign investment is the assessment of the returns that the country is receiving from mining investment. Two studies released in 1996 conclude that the overall effects of foreign investment in mining are positive at the national and regional levels and that a Dutch disease scenario does not seem probable for the future. Moreover, it is evident that had the mining boom not occurred, the country's economic growth would have been lower during the period 1988-96. It also seems clear that the military government did not have identifiable viable options for a potentially successful mining policy at the time when the great policy decisions were taken. This has been validated by the policies adopted by the two democratic governments in more recent years. This does not signify that all is perfect. Indeed there are policy changes to be adopted, but they seem to be directed at adjusting the model so that the country improves its returns rather than upsetting the whole economic-institutional model.
The nationalization process of mining companies was a global issue from the beginning of the twen... more The nationalization process of mining companies was a global issue from the beginning of the twentieth century. It first occurred in Europe for diverse reasons and at the end of the 1940s, it reached developing countries. The cause for nationalization in the latter was dominated by the search to recover a national patrimony and to regain sovereignty in countries where mining weighed too much economically compared to other activities. Transnational corporations generated so much of exports, taxes, and GDP in these countries that governments had very little room for devising national policies. The future of countries was decided in the secret of foreign board rooms of these companies, without consultation to national governments. Nationalization was also driven by the belief that by managing mining resources, the countries would accelerate economic development. Peru and Chile, indisputable leaders in mine production, experienced nationalization at the end of the 1960s and beginning of the 1970s, but the outcome was very different in each country. This paper explores the successes and failures of mining nationalization in Peru and Chile, and how the outcomes influenced mining policy during the following decades.
The energy transition relies heavily on minerals such as copper and lithium. In today's modern wo... more The energy transition relies heavily on minerals such as copper and lithium. In today's modern world, where consumers are increasingly aware of the need to protect tomorrow's natural resources, mining is expected to be not only economical but also socially and environmentally sustainable. In light of this, mining production must be competitive in these three dimensions of sustainability to meet demand, understanding that consumers will prefer a more sustainable material. This study aims to comprehend the competitiveness of copper and lithium Chilean production from a sustainable perspective using a SWOT analysis (Strengths, Weaknesses, Opportunities, and Threats) developed by a panel of experts. Based on an analysis of 165 factors driving mining's sustainability, the copper industry in Chile ranks third in the sustainability ranking for the world, while lithium ranks second. The foregoing implies that Chile, the world's leading producer of copper and second global producer of lithium, still has room to improve sustainability by introducing the following measures: (1) improving effective communication among stakeholders; (2) disseminating sustainability knowledge; (3) developing State mining policies; (4) restoring stability in the country; (5) developing a sustainable quality brand of Chilean commodities; and (6) capitalizing on valuable human capital.
ABSTRACT Preliminary initial discharge experiments at 110°C using current densities of 500ωA/cm2 ... more ABSTRACT Preliminary initial discharge experiments at 110°C using current densities of 500ωA/cm2 suggested that the optimal composition of V6O13 insertion electrodes involved additions of carbon black (5 wt %) without any polymeric electrolyte component [LiCF3SO3-(PEO)8] However subsequent cycling experiments at 120°C and 100ωA/cm2 gave disappointing results with only 10–20% of the theoretical capacity being available after 2–3 cycles. Three electrode A.C. impedance measurements revealed significant interfacial impedance values which rapidly decreased with increasing temperature so that at 146°C the cells were exhibiting an anticipated capacity of around 40–50% of the theoretical value. The performance of cells incorporating TiS2 electrodes with 15 wt % polymeric electrolyte additions was more satisfactory in that 40% of the theoretical capacity was initially available atC/10 rates at 110°C. After 250 cycles the capacity of these cells had progressively reduced to about 25%. These results are discussed with reference to available thermodynamic and transport data and relevant theoretical models developed for dynamic aspects of insertion electrode materials. An additional feature of the experiments was the promising performance of the lithium electrode in contact with the polymeric electrolyte.
Abundant evidence suggests that the massive global exploitation of copper mines over the last two... more Abundant evidence suggests that the massive global exploitation of copper mines over the last two decades led to mine aging expressed as ore grade reduction, deepening of open pits and underground operations, hardening of the rock, and increasing stripping ratios. These processes have affected the evolution and change of key environmental footprint indicators. Copper ore grade decline seems the most important of these factors and depends on variables including the rate of extraction, ore deposit geological features, introduction of new technologies, the copper price and its co-products, and the discovery and exploitation of new ore deposits. From 2001 to 2015 Chile increased its copper production by 22% and produced overall 80 million tons of copper, more than it produced in the entire 20th century. This paper explores the effects of mine aging on three key environmental footprint indicators: energy and water consumption, and greenhouse gas emissions. Electric energy consumption per ton of copper should grow in the coming decade at a significantly slower rate than in the last fifteen years because of the slowdown of the ore grade decline in mill concentrators. Additionally, a steeper decrease is expected for the emission of greenhouse gases per ton of copper.
. A model denominated Consumption Habit Exposure Model, CHEM , was developed for the calculation ... more . A model denominated Consumption Habit Exposure Model, CHEM , was developed for the calculation of human individual acute and chronic exposure to copper in drinking water. The model can estimate daily exposure of individuals as well as the maximum concentration of copper which individuals ingest during a 24-h period. The CHEM model requires carrying out a water consumption habit questionnaire and measuring the minimum and maximum concentration of copper in homes, as well as minimum and random copper concentration at work and study places. The case study employed was a representative sample of the population of Santiago, Chile. The validation of the model was established with reference to the application in a limited number of homes of the Ž . composite proportional method, CPS , used to measure human chronic ingestion of contaminants from drinking water. It was found that 4.5% of the sampled population is exposed daily to one cup of water or more at the maximum copper concentration available at the tap. The probabilities that the different age groups are exposed to one cup or more of water at c during 1 day are greater for the 20᎐64-year-old group, followed by the 64-year-old MAX group, and then by the younger age groups in descending order. Ingestion of copper from drinking water by the population of Santiago is on average 9.0% of the World Health Organization recommendations for minimum total ingestion of copper for adults, assuming that 100% of the copper contained in drinking water is absorbed.
International Biodeterioration & Biodegradation, Mar 1, 2008
... The decrease of pH at the interface copper/solution is the main factor controlling MIC of cop... more ... The decrease of pH at the interface copper/solution is the main factor controlling MIC of copper (Webster et al., 2000). ... (Webster et al., 1996); Acidovorax delafieldii, Cytophaga johnsonae, and Micrococcus kristinae (Critchley and Fallowfield, 2001); Acidovorax sp. ...
Journal Of Environmental Science And Health, Part A, Nov 1, 2006
Daily exposures to chemicals in drinking water are of importance in risk assessment to human heal... more Daily exposures to chemicals in drinking water are of importance in risk assessment to human health. However, exposure assessment of chemicals in drinking water has seldom been performed in China. Until now, no such a detailed exposure assessment was reported in China. The aim of the present paper is to describe the scenes of daily exposure to Cu and Zn in drinking water by the population of Shanghai, China in the summer of 2003. A total of 163 volunteers and/or homes were selected to be statistically representative of the population of Shanghai, China. The Modified Consumption Habit Exposure Model (CHEM) method combined with the measurement of metals concentrations in stagnant water and actual ingested water was used to describe the daily exposure. The Consumption Habit Exposure Model method results showed that water consumption ranged from 1.7 to 2.2 L/day, varied with different age, gender and work location groups. Chemical results showed that the average Cu and Zn concentrations in stagnant water were much higher than those in actual ingested water (13.5 microg/L and 1.55 mg/L vs. 10.8 microg/L and 0.29 mg/L). Exposure assessment results also showed that volunteers had the highest exposure from the time of after breakfast to before dinner, and had the lowest exposure during the 15 minutes before sleeping. It was also showed that there were few volunteers directly exposed to stagnant water, although six hours stagnant time can be reached in most of the homes in Shanghai in the morning. The mean daily exposures to Cu and Zn were 0.36 microg/kg/day and 0.01 mg/kg/day. Daily intakes of Cu and Zn from drinking water by Shanghai people were 1.8% and 4.4% of the World Health Organization recommendations for minimum total intakes of Cu and Zn for adults, respectively.
... This focus typically recognizes and rewards mineral exploration results only if they positive... more ... This focus typically recognizes and rewards mineral exploration results only if they positively affect a company's cash flow portfolio (existing mines and ... short-run fluctuations, real copper prices show little long-run trend, neither rising nor falling greatly (Svedberg and Tilton, 2006 ...
Water Science & Technology: Water Supply, Dec 1, 2010
The presence of natural organic matter (NOM) in drinking water can increase the levels of copper ... more The presence of natural organic matter (NOM) in drinking water can increase the levels of copper released from copper pipes to water and inhibit the formation of protective deposits such as malachite. Since adsorption of NO M on copper pipes surfaces is believed to be one of mechanisms that explains this phenomenom, the objective of this study was to determine kinetics and the adsorption equilibrium of main components of NOM, humic acid (HA) and fulvic acid (FA), onto copper surfaces. The kinetics and equilibrium adsorption of HA and FA on copper foils were examined using batch experiments at 22°C. HA and FA followed pseudo second-order kinetics adsorption. Rate constants measured were 2.59 x 10 -1 (mgTOC cm -2 h -1 ) for HA and 3.13 x 10 -1 (mgTOC cm -2 h -1 ) for FA. The adsorption behavior of HA and FA on the copper surface is in accordance with the Langmuir adsorption isotherm. Langmuir adsorption constants measured were 5.98 x 10 -2 L mg -1 for HA and 4 .78 x 10 -2 L mg -1 for FA. The copper foils exposed during five months to FA formed malachite deposits, whereas those exposed to H A did not and just cuprite was found. The results of this study showed that both HA as well as FA adsorption on copper surfaces is favored and no significant differences were found in the adsorption parameters calculated for both compounds. However, the inhibition of the malachite precipitation could be attributed to the HA adsorption.
Abstract Several studies dealt in the past decades with future predictions of the copper demand, ... more Abstract Several studies dealt in the past decades with future predictions of the copper demand, motivated mainly by potential copper shortages that could arise due to insufficient reserves. It is known that there was never a shortage of reserves in order to satisfy demand in the last century and up to the present time. This paper addresses two questions. Did these concerns arise due to excessive demand forecasts, or due to stagnating reserves assumption, or due to both aspects? The article evaluates some of these predictions of future copper demand and compares forecasts with the real metal demand that materialized in past years. Also, it analyses the reserve assumptions of several studies and compares them with what really happened with copper reserves. In the case of recent forecast models that span into future years, whose copper demand is not known yet, a backcasting method was used in order to estimate forecasts, which consists of applying the model in the past. Five out of the seven models rerun in the original periods overestimated demand and two out of them considered that reserves were a fixed stock. Also, the two models studied by the backcasting method considered that reserves were a fixed stock. The four models that considered reserves as a fixed stock run out of reserves, irrespective of whether they overestimated or underestimated demand. These results suggest that predictions of a future scarcity of copper could be mainly attributed to the assumption of a fixed stock of reserves and not necessarily to overestimations of demand. The remaining five models did not consider the future availability of copper.
ABSTRACT Modelling and prediction of the copper concentration released from copper plumbing tubes... more ABSTRACT Modelling and prediction of the copper concentration released from copper plumbing tubes due to corrosion, dissolution, precipitation and other processes has not previously been successful. The model presented here is based on a set of dissolution and precipitation reactions, equilibrium between species in solution and solids, mass balance, kinetic expressions, adsorption isotherms, and surface area coverage by precipitates.The model developed has created two major outputs: first; it is the most conclusive collection of mechanistic considerations to date; and second; reasonable correlations between the model and actual data have been obtained for a broad range of waters.
Daily intakes of metals in drinking water are of extreme importance in risk assessment to human h... more Daily intakes of metals in drinking water are of extreme importance in risk assessment to human health. Some papers focused on this topic, but most of them did not consider the effect of age, gender and work location on daily intakes of metals in drinking water. The objective of present paper is to estimate the levels of Cu, Zn and As ingestion in drinking water in Shanghai, China and the effect of age, gender and work location on daily intakes of these metals. It was also the first time that such a detailed investigation on daily intakes of metals in drinking water was carried out in China in recent years. Drink/Sample (D/S) method was used to estimate the daily intakes of Cu, Zn and As in drinking water. The mean concentrations of Cu, Zn and As in drinking water were 10.8 Ag/l, 0.29 mg/l and 0.91 Ag/l, which were lower than U.S. EPA's Drinking Water Equivalent Level (DWEL) and WHO guideline values. The average daily intakes of Cu, Zn and As in drinking water was 21.12 Ag/d, 0.65 mg/d, and 1.83 Ag/d, which were on average 0.01%, 1.1% and 1.5% of the provisional maximum tolerable daily intake (PMTDI) set by the Joint FAO/ WHO Expert Committee. There was a significant difference in daily intake of Zn for different work locations ( P = 0.04). But no other significant differences in daily intakes of metals in drinking water were found according to age, gender and work location.
This paper discusses the mining development policies in Chile in the period 1974-96. This period ... more This paper discusses the mining development policies in Chile in the period 1974-96. This period includes the military government that took over the country from socialist President Allende in 1973, and the return to democracy with the election of President Aylwin in 1989 and of President Frei in 1993. The paper analyses the economic and mining policies of the military and democratic periods, and then the country's mining investment, production and exports under the prism of the main institutional development policies pursued. The analysis focuses on copper mining, where investment and growth have created a mining boom unprecedented worldwide in this century since the discovery of the flotation process in the early 1900s. Thus it is of special relevance to examine the set of circumstances that has made this boom possible. The main discussion during this period regards the legitimacy of foreign investment in mining vs the capacity and potential of the state-owned company Codelco to be a protagonist of mining development. While the more liberal sectors of the political spectrum have supported the privatization of Codelco, the more conservative sectors support the continued ownership of Codelco by the state. This discussion will be of no great consequence if the mining boom continues. Nevertheless aspects of the discussion in 1996 questioned the economic development model employed by the country since 1974. Crucial for the legitimacy of foreign investment is the assessment of the returns that the country is receiving from mining investment. Two studies released in 1996 conclude that the overall effects of foreign investment in mining are positive at the national and regional levels and that a Dutch disease scenario does not seem probable for the future. Moreover, it is evident that had the mining boom not occurred, the country's economic growth would have been lower during the period 1988-96. It also seems clear that the military government did not have identifiable viable options for a potentially successful mining policy at the time when the great policy decisions were taken. This has been validated by the policies adopted by the two democratic governments in more recent years. This does not signify that all is perfect. Indeed there are policy changes to be adopted, but they seem to be directed at adjusting the model so that the country improves its returns rather than upsetting the whole economic-institutional model.
The nationalization process of mining companies was a global issue from the beginning of the twen... more The nationalization process of mining companies was a global issue from the beginning of the twentieth century. It first occurred in Europe for diverse reasons and at the end of the 1940s, it reached developing countries. The cause for nationalization in the latter was dominated by the search to recover a national patrimony and to regain sovereignty in countries where mining weighed too much economically compared to other activities. Transnational corporations generated so much of exports, taxes, and GDP in these countries that governments had very little room for devising national policies. The future of countries was decided in the secret of foreign board rooms of these companies, without consultation to national governments. Nationalization was also driven by the belief that by managing mining resources, the countries would accelerate economic development. Peru and Chile, indisputable leaders in mine production, experienced nationalization at the end of the 1960s and beginning of the 1970s, but the outcome was very different in each country. This paper explores the successes and failures of mining nationalization in Peru and Chile, and how the outcomes influenced mining policy during the following decades.
The energy transition relies heavily on minerals such as copper and lithium. In today's modern wo... more The energy transition relies heavily on minerals such as copper and lithium. In today's modern world, where consumers are increasingly aware of the need to protect tomorrow's natural resources, mining is expected to be not only economical but also socially and environmentally sustainable. In light of this, mining production must be competitive in these three dimensions of sustainability to meet demand, understanding that consumers will prefer a more sustainable material. This study aims to comprehend the competitiveness of copper and lithium Chilean production from a sustainable perspective using a SWOT analysis (Strengths, Weaknesses, Opportunities, and Threats) developed by a panel of experts. Based on an analysis of 165 factors driving mining's sustainability, the copper industry in Chile ranks third in the sustainability ranking for the world, while lithium ranks second. The foregoing implies that Chile, the world's leading producer of copper and second global producer of lithium, still has room to improve sustainability by introducing the following measures: (1) improving effective communication among stakeholders; (2) disseminating sustainability knowledge; (3) developing State mining policies; (4) restoring stability in the country; (5) developing a sustainable quality brand of Chilean commodities; and (6) capitalizing on valuable human capital.
ABSTRACT Preliminary initial discharge experiments at 110°C using current densities of 500ωA/cm2 ... more ABSTRACT Preliminary initial discharge experiments at 110°C using current densities of 500ωA/cm2 suggested that the optimal composition of V6O13 insertion electrodes involved additions of carbon black (5 wt %) without any polymeric electrolyte component [LiCF3SO3-(PEO)8] However subsequent cycling experiments at 120°C and 100ωA/cm2 gave disappointing results with only 10–20% of the theoretical capacity being available after 2–3 cycles. Three electrode A.C. impedance measurements revealed significant interfacial impedance values which rapidly decreased with increasing temperature so that at 146°C the cells were exhibiting an anticipated capacity of around 40–50% of the theoretical value. The performance of cells incorporating TiS2 electrodes with 15 wt % polymeric electrolyte additions was more satisfactory in that 40% of the theoretical capacity was initially available atC/10 rates at 110°C. After 250 cycles the capacity of these cells had progressively reduced to about 25%. These results are discussed with reference to available thermodynamic and transport data and relevant theoretical models developed for dynamic aspects of insertion electrode materials. An additional feature of the experiments was the promising performance of the lithium electrode in contact with the polymeric electrolyte.
Abundant evidence suggests that the massive global exploitation of copper mines over the last two... more Abundant evidence suggests that the massive global exploitation of copper mines over the last two decades led to mine aging expressed as ore grade reduction, deepening of open pits and underground operations, hardening of the rock, and increasing stripping ratios. These processes have affected the evolution and change of key environmental footprint indicators. Copper ore grade decline seems the most important of these factors and depends on variables including the rate of extraction, ore deposit geological features, introduction of new technologies, the copper price and its co-products, and the discovery and exploitation of new ore deposits. From 2001 to 2015 Chile increased its copper production by 22% and produced overall 80 million tons of copper, more than it produced in the entire 20th century. This paper explores the effects of mine aging on three key environmental footprint indicators: energy and water consumption, and greenhouse gas emissions. Electric energy consumption per ton of copper should grow in the coming decade at a significantly slower rate than in the last fifteen years because of the slowdown of the ore grade decline in mill concentrators. Additionally, a steeper decrease is expected for the emission of greenhouse gases per ton of copper.
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Papers by Gustavo Lagos