scholarly journals Carbon Mineralization with North American PGM Mine Tailings—Characterization and Reactivity Analysis

Minerals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 844
Author(s):  
Caleb M. Woodall ◽  
Xueya Lu ◽  
Gregory Dipple ◽  
Jennifer Wilcox
Keyword(s):  
Mine Tailings ◽  
Low Cost ◽  
Carbon Mineralization ◽  
Platinum Group Metals ◽  
Ion Concentration ◽  
Ambient Conditions ◽  
Plagioclase Feldspar ◽  
Fossil Energy ◽  
Global Transition ◽  
Storage Facilities

Global efforts to combat climate change call for methods to capture and store CO2. Meanwhile, the global transition away from fossil energy will result in increased production of tailings (i.e., wastes) from the mining of nickel and platinum group metals (PGMs). Through carbon mineralization, CO2 can be permanently stored in calcium- and magnesium-bearing mine tailings. The Stillwater mine in Nye, Montana produces copper, nickel, and PGMs, along with 1 Mt of tailings each year. Stillwater tailings samples have been characterized, revealing that they contain a variety of mineral phases, most notably Ca-bearing plagioclase feldspar. Increases in inorganic carbon in the tailings and ion concentration in the tailings storage facilities suggest carbonation has taken place at ambient conditions over time within the tailings storage facilities. Two experiments were performed to simulate carbon mineralization at ambient temperature and pressure with elevated CO2 concentration (10% with N2), revealing that less than 1% of the silicate-bound calcium within the tailings is labile, or easily released from silicate structures at low-cost ambient conditions. The Stillwater tailings could be useful for developing strategies of waste management as production of nickel and PGM minerals increases during the global transition away from fossil energy, but further work is needed to develop a process that can realize their full carbon storage potential.

scholarly journals Solar Thermochemical Hydrogen Production in the USA

2021 ◽  
Vol 13 (14) ◽  
pp. 7804
Author(s):  
Christoph Falter ◽  
Andreas Sizmann
Keyword(s):  
Hydrogen Production ◽  
Large Scale ◽  
Low Cost ◽  
The United States ◽  
Solar Irradiation ◽  
Transport Sector ◽  
Fossil Energy ◽  
The Us ◽  
The Usa ◽  
Solar Thermochemical

Hydrogen produced from renewable energy has the potential to decarbonize parts of the transport sector and many other industries. For a sustainable replacement of fossil energy carriers, both the environmental and economic performance of its production are important. Here, the solar thermochemical hydrogen pathway is characterized with a techno-economic and life-cycle analysis. Assuming a further increase of conversion efficiency and a reduction of investment costs, it is found that hydrogen can be produced in the United States of America at costs of 2.1–3.2 EUR/kg (2.4–3.6 USD/kg) at specific greenhouse gas emissions of 1.4 kg CO2-eq/kg. A geographical potential analysis shows that a maximum of 8.4 × 1011 kg per year can be produced, which corresponds to about twelve times the current global and about 80 times the current US hydrogen production. The best locations are found in the Southwest of the US, which have a high solar irradiation and short distances to the sea, which is beneficial for access to desalinated water. Unlike for petrochemical products, the transport of hydrogen could potentially present an obstacle in terms of cost and emissions under unfavorable circumstances. Given a large-scale deployment, low-cost transport seems, however, feasible.

scholarly journals Lifetime Analysis of Rubber Gasket Composed of Methyl Vinyl Silicone Rubber with Low-Temperature Resistance

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Young-Doo Kwon ◽  
Seong-Hwa Jun ◽  
Ji-Min Song
Keyword(s):  
Silicone Rubber ◽  
Mechanical Load ◽  
Low Cost ◽  
Accelerated Life Test ◽  
Parameter Method ◽  
Ambient Conditions ◽  
Methyl Vinyl ◽  
Accelerated Life ◽  
Elastomeric Materials ◽  
Lifetime Analysis

Most machines and instruments constantly require elastomeric materials like rubber for the purposes of shock absorption, noise attenuation, and sealing. The material properties and accurate lifetime prediction of rubber are closely related to the quality of machines, especially their durability and reliability. The properties of rubber-like elastomers are influenced by ambient conditions, such as temperature, environment, and mechanical load. Moreover, the initial properties of rubber gaskets must be sustained under working conditions to satisfy their required function. Because of its technical merits, as well as its low cost, the highly accelerated life test (HALT) is used by many researchers to predict the long-term lifetime of rubber materials. Methyl vinyl silicone rubber (VMQ) has recently been adopted to improve the lifetime of automobile radiator gaskets. A four-parameter method of determining the recovery ability of the gaskets was recently published, and two revised methods of obtaining the recovery were proposed for polyacrylate (ACM) rubber. The recovery rate curves for VMQ were acquired using the successive zooming genetic algorithm (SZGA). The gasket lifetime for the target recovery (60%) of a compressed gasket was computed somewhat differently depending on the selected regression model.

Phosphate biogeochemical barrier for uranium in situ immobilization in an aquifer nearby sludge repository

2021 ◽  
Author(s):  
Grigory Artemiev ◽  
Alexey Safonov ◽  
Nadezhda Popova
Keyword(s):  
Essential Elements ◽  
Ion Concentration ◽  
Soluble Form ◽  
High Concentration ◽  
Rapid Reduction ◽  
Near Surface ◽  
Nitrate Ions ◽  
Uranium Migration ◽  
Storage Facilities

<p>Uranium migration in the oxidized environment of near-surface groundwater is a typical problem of many radiochemical, ore mining and ore processing enterprises that have sludge storage facilities on their territory. Uranium migration, as a rule, occurs against a high salt background due to the composition of the sludge: primarily, nitrate and sulfate anions and calcium cations. One of the ways to prevent the uranium pollution is geochemical or engineering barriers. For uranium immobilization, it is necessary to create conditions for its reduction to a slightly soluble form of uraninite and further mineralization, for example, in the phosphate form. An important factor contributing to the rapid reduction of uranium is a in the redox potential decreasing and the removal of nitrate ions, which can be achieved through the activation of microflora. It should be added that phosphate itself is one of the essential elements for the development of microflora. This work was carried out in relation to the upper aquifer (7-12 m) near the sludge storage facilities of ChMZ, which is engaged in uranium processing and enrichment. One of the problems of this aquifer, in addition to the high concentration of nitrate ions (up to 15 g / l), is the high velocity of formation waters.<br>In laboratory conditions, the compositions of injection solutions were selected containing sources of organic matter to stimulate the microbiota development and phosphates for uranium mineralization. When developing the injection composition, special attention was paid to assessing the formation of calcite deposits in aquifer conditions to partially reduce the filtration parameters of the horizon and reduce the rate of movement of formation waters. This must be achieved to ensure the possibility of long-term deposition of uranium and removal of nitrate. The composition of the optimal solution was selected and in a series of model experiments the mineral phases containing the lowest hydrated form of the uranium-containing phosphate mineral meta-otenite were obtained.<br>In situ mineral phosphate barrier Formation field tests were carried out in water horizon conditions in a volume of 100m3 by injection of an organic and phosphates mixture. As a result, at the first stage of field work, a significant decreasing nitrate ion concentration, and reducing conditions formation coupled with the dissolved uranium concentration of decreasing were noted.</p>

scholarly journals Removal of Zinc ions from industrial wastewater with wool fibers

2010 ◽  
Vol 7 (3) ◽  
pp. 1193-1201
Author(s):  
Baghdad Science Journal
Keyword(s):  
Acid Concentration ◽  
Contact Time ◽  
Industrial Wastewater ◽  
Metal Ion ◽  
Low Cost ◽  
Zinc Ion ◽  
Ion Concentration ◽  
Natural Material ◽  
Zinc Ions ◽  
Wool Fibers

In this research, the efficiency of low-cost unmodified wool fibers were used to remove zinc ion from industrial wastewater. Removal of zinc ion was achieved at 99.52% by using simple wool column. The experiment was carried out under varying conditions of (2h) contact time, metal ion concentration (50mg/l), wool fibers quantity to treated water (70g/l), pH(7) & acid concentration (0.05M). The aim of this method is to use a high sensitive, available & cheep natural material which applied successfully for industrial wastewater& synthetic water, where zinc ion concentration was reduced from (14.6mg/l) to (0.07mg/l) & consequently the hazardous effect of contamination was minimized.

scholarly journals Adsorption Study of Cu2+ Ions from Aqueous Solutions by Bael Flowers (Aegle marmelos)

2020 ◽  
Vol 11 (4) ◽  
pp. 11891-11904
Keyword(s):  
Aqueous Solutions ◽  
Adsorption Capacity ◽  
Metal Ion ◽  
Low Cost ◽  
Sem Analysis ◽  
Ion Concentration ◽  
Maximum Adsorption Capacity ◽  
Aegle Marmelos ◽  
Batch Mode ◽  
Initial Ph

In the present study, batch mode adsorption was carried out to investigate the adsorption capacity of dried bael flowers (Aegle marmelos) for the adsorptive removal of Cu(II) ions from aqueous solutions by varying agitation time, initial metal concentration, the dose of adsorbent, temperature, and initial pH of the Cu(II) ion solution. The percentage removal of 98.7% was observed at 50 ppm initial metal ion concentration, 0.5 g/100.00 cm3 adsorbent dosage, within the contact time of 120 minutes at 30 ºC in the pH range of 4 – 7. The sorption processes of Cu(II) ions was best described by pseudo-second-order kinetics. Langmuir isotherm had a good fit with the experimental data with 0.97 of correlation coefficient (R2), and the maximum adsorption capacity obtained was 23.14 mg g-1 at 30 ºC. The results obtained from sorption thermodynamic studies suggested that the adsorption process is exothermic and spontaneous. SEM analysis showed tubular voids on the adsorbent. FTIR studies indicated the presence of functional groups like hydroxyl, –C-O, –C=O, and amide groups in the adsorbent, which can probably involve in metal ion adsorption. Therefore, dried bael flowers can be considered an effective low-cost adsorbent for treating Cu(II) ions.

scholarly journals The presence of sianobacteria and algae in biological soil crusts on South African goldmine tailings

2012 ◽  
Vol 31 (1) ◽  
Author(s):  
T. Orlekowsky ◽  
A. Levanets ◽  
S. J. Van Wyk ◽  
A. Venter
Keyword(s):  
South African ◽  
Mine Tailings ◽  
Biological Soil Crusts ◽  
Soil Crusts ◽  
Physical And Chemical ◽  
Storage Facilities

The aim was to investigate the presence of cyanobacteria as well as algae on minetailings storage facilities that have undergone rehabilitation for different periodes of time aswell as to correlate the presence of these species with the physical and chemical characteristicsof the mine tailings.

Removal of Pb(II) and Cd(II) From Aqueous Solution by Adsorption Using Agrowaste-Modified Kaolinite Clay

2021 ◽  
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Metal Ions ◽  
Metal Ion ◽  
Low Cost ◽  
Ion Concentration ◽  
Kaolinite Clay ◽  
Adsorbent Surface ◽  
Initial Adsorption ◽  
Adsorption Rates

This study showed that kaolinite clay modified with Moringa oleifera pods is a promising low cost adsorbent for the removal of metals from aqueous solution because the resultant composite has higher adsorption capacities, and hence a better metal ions removal efficiency. The efficiencies of these adsorbents for the removal of Pb (II) and Cd (II) ions from aqueous solutions were studied as a function of pH, time, adsorbate concentration and adsorbent dose. Adsorption results showed that pH did significantly affect removal of heavy metal ions between pH 3 and 6. Increasing contact time and initial metal ion concentration increased the sorption capacity of the adsorbent for the metal ions. Adsorbent dosage indicated mainly surface phenomena involving sharing of electrons between the adsorbent surface and the metal ion species. The adsorption of metal ions from aqueous solutions of both metal ions at different initial metal ion concentrations reduced the initial adsorption rates of the adsorption of Pb (II) and Cd (II) by unmodified and modified kaolinite clay.

Novel electrolyte additive of graphene oxide for prolonging the lifespan of Zinc-ion batteries

2021 ◽  
Author(s):  
Xuyang Wang ◽  
Alina Kirianova ◽  
Xieyu Xu ◽  
Yanguang Liu ◽  
Olesya Kapitanova ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Coulombic Efficiency ◽  
Low Cost ◽  
Concentration Field ◽  
Phase Field Model ◽  
Deposition Process ◽  
Zinc Ion ◽  
Ion Concentration ◽  
Environmental Friendliness ◽  
Nucleation Overpotential

Abstract Aqueous zinc-ion batteries have attracted the attention of the industry due to their low cost, good environmental friendliness, and competitive gravimetric energy density. However, zinc anodes, similar to lithium, sodium and other alkali metal anodes, are also plagued by dendrite problems. Zinc dendrites can penetrate through polymer membranes, and even glass fiber membranes which seriously hinders the development and application of aqueous zinc-ion batteries. To resolve this issue, certain additives are required. Here we have synthesized an electrochemical graphene oxide with novel electrolyte based on tryptophan, which allows to obtain few-layered sheets with a remarkably uniform morphology, good aqueous solution dispersion, easy preparation and environmental friendliness. We used this electrochemical graphene oxide as an additive to the electrolyte for aqueous zinc-ion batteries. The results of phase-field model combined with experimental characterization revealed that the addition of this material effectively promotes the uniform distribution of the electric field and the Zn-ion concentration field, reduces the nucleation overpotential of Zn metal, and provides a more uniform deposition process on the metal surface and improved cyclability of the aqueous Zn-ion battery. The resultant Zn|Zn symmetric battery with the electrochemical graphene oxide additive affords a stable Zn anode, which provided service for more than 500 hours at 0.2 mA cm-2 and even more than 250 hours at 1.0 mA cm-2. The Coulombic efficiency (98.7%) of Zn|Cu half-cells and thus cyclability of aqueous Zn-ion batteries using electrochemical graphene oxide is significantly better compared to the additive-free electrolyte system. Therefore, our approach paves a promising avenue to foster the practical application of aqueous Zn-ion batteries for energy storage.

Maximizing Cost Efficiencies in Agricultural Supply Chains in Pakistan Using Smart Technologies

2021 ◽  
pp. 54-86
Author(s):  
Sayed Muhammed Irfan ◽  
Mehreen Kausar Azam
Keyword(s):  
Supply Chain ◽  
Load Shedding ◽  
Agricultural Product ◽  
Supply Chain Network Design ◽  
Supply Chain Network ◽  
Ambient Conditions ◽  
Cost Efficiencies ◽  
Solar Powered ◽  
Smart Technologies ◽  
Storage Facilities

This chapter introduces the idea of integrating storage facilities in an agriculture supply chain within the established framework of supply chain network design to leverage the underlying powerful optimization technology for maximizing supply chain surplus. Further, storage facilities, particularly for perishable farm products, require to be maintained at certain ambient conditions to retain their quality. Currently, adequate storage facilities do not exist at strategic locations which incur very substantial post-harvest losses. The idea of solar-powered storage systems with a modular configuration has also been proposed. There are two principal reasons for this: (1) Pakistan has enormous solar power potential, and (2) there are rampant load-shedding problems in the country. While tomatoes have been selected as a typical product to develop the entire discourse, the resulting integrated model may be just as conveniently applied to any other agricultural product.

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