scholarly journals Current key options for management of industrial alkaline waste of alumina production (red mud)

2021 ◽  
Vol 284 ◽  
pp. 01003
Author(s):  
Htet Ye Aung ◽  
Alexander Boyarintsev ◽  
Sergey Stepanov ◽  
Andrei Shoustikov
Keyword(s):  
Red Mud ◽  
Large Scale ◽  
Cost Effective ◽  
Industrial Wastes ◽  
Toxic Waste ◽  
Alumina Production ◽  
The Sustainable Development ◽  
The World ◽  
Liquid Products ◽  
Bauxite Ore

Due to the ever-increasing demand of the world economy for aluminum, its alloys and compounds, the production of this metal is increasing annually throughout the world. This leads to an increase in the industrial production of alumina, which is obtained from bauxite ore in the Bayer process. After recovering the bulk of the aluminum from the bauxite ore, there remains a residue which is highly alkaline toxic waste, which is also called bauxite residues (tailings) or red mud (RM). About 140-150 million tons of RM are produced annually and almost 4 billion tons have already been accumulated. At the moment, the problem of RM recycling and the development of effective and cost-effective approaches to their reprocessing is extremely urgent. Reducing RM affects economic, environmental, social areas and is a prerequisite for the sustainable development of nature and society. Despite active scientific research and efforts to develop and optimize various methods for RM recycling and reprocessing, the problem of an annual increase in their volumes around the world remains unresolved. Recently, promising and efficient processes have been proposed that allows for the complex reprocessing of RM with the extraction of a number of valuable liquid products that may be in demand in various fields of industry. This allows to focus on large-scale disposal of RM and can be a solution to the problem of handling these industrial wastes. The article considers the main current trends in the field of management of various types of RM with a focus on complex reprocessing and zero waste concepts.

scholarly journals Complex reprocessing of industrial alkaline waste of alumina production (red mud) for solving raw materials and environmental problems

2021 ◽  
Vol 258 ◽  
pp. 08026
Author(s):  
Alexander Boyarintsev ◽  
Htet Ye Aung ◽  
Sergey Stepanov ◽  
Andrei Shoustikov
Keyword(s):  
Red Mud ◽  
Large Scale ◽  
Raw Materials ◽  
Toxic Waste ◽  
High Tech ◽  
Secondary Source ◽  
Critical Metals ◽  
Alumina Production ◽  
Carbon Dioxide Gas ◽  
Iron Aluminum

Red mud are industrial large-scale toxic wastes of bauxite ore processing according to the Bayer method. They contain macrocomponents such as iron, aluminum, calcium, silicon, as well as a number of the most valuable and critical metals (microcomponents): scandium, gallium, germanium and rare earth elements (REEs), which are used in modern high-tech industry. Due to the relatively high content of scandium and REEs, red mud can be considered as a promising secondary source. Significant amounts of accumulated red mud and new flows of this waste entering the slime storage facilities need to be processed to obtaine the required valuable products. Development of complex reprocessing approach play an important role in addressing the problem of the elimination of red mud as toxic waste. Within the framework of this subject, the report considers the concept of complex reprocessing of Bogoslovsky Aluminum Plant (Russia) red mud, which includes the extraction of aluminum, scandium, REEs, zirconium and the production of iron-containing concentrate for ferrous metallurgy. The use of low-aggressive carbonate media and carbonation method using carbon dioxide gas characterizes this approach as more environmentally and technologically safe. The development of effective technology for utilization of red mud will not only provide a source of critical raw materials, but also solve the global environmental problem.

scholarly journals Effect of red mud addition on the corrosion parameters of reinforced concrete evaluated by electrochemical methods

2012 ◽  
Vol 5 (4) ◽  
pp. 451-467 ◽  
Author(s):  
D.V. Ribeiro ◽  
J.A. Labrincha ◽  
M.R. Morelli
Keyword(s):  
Electrical Resistivity ◽  
Reinforced Concrete ◽  
Red Mud ◽  
Corrosion Potential ◽  
Corrosion Process ◽  
Bayer Process ◽  
Alumina Production ◽  
High Ph ◽  
High Electrical Resistivity ◽  
Bauxite Ore

Red mud, the main waste generated in aluminum and alumina production from bauxite ore by the Bayer process, is considered "hazardous" due to its high pH. The high pH also provides greater protection of rebars, which is reflected in the low corrosion potential and high electrical resistivity (filler effect) of concrete. The corrosion potential was monitored by electrochemical measurements and the electrical resistivity was evaluated using sensors embedded in concrete test specimens. The results showed that the addition of red mud is beneficial to concrete, reducing its corrosion potential and increasing its electrical resistivity. Red mud proved to be a promising additive for concrete to inhibit the corrosion process.

Reflecting on Our Times: Valuing Transformative Leadership in Real-World “Living Systems”

2021 ◽  
pp. 109821402098207
Author(s):  
John Atkinson ◽  
Florence Lasbennes ◽  
David Nabarro
Keyword(s):  
Sustainable Development ◽  
Large Scale ◽  
Sustainable Development Goals ◽  
Transformative Leadership ◽  
Living Systems ◽  
The Sustainable Development ◽  
2030 Agenda ◽  
The World ◽  
Development Goals ◽  
Key Aspects

We present this brief reflection on key aspects of the 2030 Agenda for Sustainable Development and the implications of the worldwide focus on achieving the sustainable development goals as external observers of the evaluation endeavor around the world. We have conducted and participated in evaluations, but it is not our primary field of work and we are not engaged in the global community of evaluation specialists. However, we believe that the urgency of the challenges confronting the world today should inspire those influencing and shaping evaluation internationally to focus much more fiercely on the value of evaluation and its implications for leadership at all levels and in all fields of work. We propose that evaluation as practice should support and help inspire, value, and evaluate the type of leadership that the world needs now—dynamic and purposeful “living systems” leaders working toward large-scale, drastic change.

scholarly journals Synthesis of Amorphous Aluminosilicates from Bintan’s Red Mud as Alumina Source

2018 ◽  
Vol 18 (4) ◽  
pp. 580
Author(s):  
Futri Wulandari ◽  
Eka Putra Ramdhani ◽  
Yatim Lailun Ni’mah ◽  
Ahmad Anwarud Dawam ◽  
Didik Prasetyoko
Keyword(s):  
Red Mud ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Structure Directing Agent ◽  
Alumina Production ◽  
Hydrolysis Method ◽  
Alkali Fusion ◽  
Silica Source ◽  
Bauxite Ore ◽  
Adsorption Desorption

Red mud is a generated by-product in alumina production from bauxite ore. In this study, Bintan’s red mud has been used as alumina and silica source to synthesize amorphous mesoporous aluminosilicates material. Alkali fusion method with a NaOH/red mud ratio 0.8; 1.0; 1.2; 1.4 and 1.5 followed by hydrolysis method was used to extract dissolved alumina and silica from red mud. Synthesis of amorphous aluminosilicates by hydrothermal method was conducted at 80 °C for 24 h. Cetyltrimethylammonium bromide (CTABr) was added as the structure directing agent. Aluminosilicate products were characterized using FTIR spectroscopy (Fourier Transform Infra-Red Spectroscopy), XRD (X-ray Diffraction), SEM (Scanning Electron Microscopy), and nitrogen adsorption-desorption. XRD and SEM result shows that the product was amorphous with low uniformity in terms of surface morphology and particle size. Nitrogen adsorption-desorption profile shows that all aluminosilicates products has a meso pore structure, confirmed by the highest pore distribution at 3.05–17.70 nm. The highest surface area and pore volume were obtained in ASM 0.8 (NaOH/red mud ratio = 0.8) i.e. 177.97 m2/g and 1.09 cm3/g, respectively.

scholarly journals Bulk Utilization of Red Mud in Geopolymer Based Products

2020 ◽  
Vol 12 (2) ◽  
pp. 86-91
Author(s):  
Abhisek Mohapatra ◽  
Prasanta Bose ◽  
Sagar S Pandit ◽  
Sanjay Kumar ◽  
T.C. Alex
Keyword(s):  
Red Mud ◽  
Ash Content ◽  
Target Strength ◽  
Alkali Concentration ◽  
Alumina Production ◽  
Ore Processing ◽  
Fine Size ◽  
Bauxite Ore ◽  
Alumina Industry ◽  
And Storage

Red Mud is the solid residue generated from Alumina refinery during the process of bauxite ore processing through Bayer’s process. Typical generation of red mud is 1.5 tons of red mud per ton of alumina produced. The disposal and storage of red mud has been a concern for the alumina industry since its inception, more than a hundred years ago. With the increase in alumina production, the magnitude of the problem is getting multiplied. Its alkaline nature (Na2O ~ 3-7%) and fine size make red mud unsuitable for many applications; a limited utilization is reported in cement industries as one of the raw mix components for cement. The present work deals with the utilization of red mud in geopolymer based paving blocks. Alumina, silica and alkali are the essential items required for geopolymer preparation. Having all these in red mud, the current study attempted to use the same in geopolymer based products. The focus has been on bulk utilization of red mud; target strength of 20 MPa after 28 days of curing (M20 grade) has been the goal as this strength is sufficient for many applications. The study focused on optimizing the red mud content, alkali concentration, fly ash content, etc. The samples are tested for its compressive strength and leachability. The study reveals that significant amount of red mud incorporation is possible with products conforming to USEPA 1311 norms.

scholarly journals A universal co-solvent dilution strategy enables facile and cost-effective fabrication of perovskite photovoltaics

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Hong Zhang ◽  
Kasra Darabi ◽  
Narges Yaghoobi Nia ◽  
Anurag Krishna ◽  
Paramvir Ahlawat ◽  
...  
Keyword(s):  
Large Scale ◽  
Perovskite Solar Cells ◽  
Precursor Solution ◽  
Cost Effective ◽  
Toxic Waste ◽  
High Concentration ◽  
Colloidal Chemistry ◽  
High Volatility ◽  
Key Issues ◽  
The Stability

AbstractCost management and toxic waste generation are two key issues that must be addressed before the commercialization of perovskite optoelectronic devices. We report a groundbreaking strategy for eco-friendly and cost-effective fabrication of highly efficient perovskite solar cells. This strategy involves the usage of a high volatility co-solvent, which dilutes perovskite precursors to a lower concentration (<0.5 M) while retaining similar film quality and device performance as a high concentration (>1.4 M) solution. More than 70% of toxic waste and material cost can be reduced. Mechanistic insights reveal ultra-rapid evaporation of the co-solvent together with beneficial alteration of the precursor colloidal chemistry upon dilution with co-solvent, which in-situ studies and theoretical simulations confirm. The co-solvent tuned precursor colloidal properties also contribute to the enhancement of the stability of precursor solution, which extends its processing window thus minimizing the waste. This strategy is universally successful across different perovskite compositions, and scales from small devices to large-scale modules using industrial spin-coating, potentially easing the lab-to-fab translation of perovskite technologies.

scholarly journals Influence of Na2CO3 and K2CO3 Addition on Iron Grain Growth during Carbothermic Reduction of Red Mud

Metals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1313 ◽  
Author(s):  
Dmitry Zinoveev ◽  
Pavel Grudinsky ◽  
Andrey Zakunov ◽  
Artem Semenov ◽  
Maria Panova ◽  
...  
Keyword(s):  
Magnetic Separation ◽  
Grain Growth ◽  
Red Mud ◽  
Carbothermic Reduction ◽  
Reduction Roasting ◽  
Alumina Production ◽  
Iron Aluminum ◽  
Bauxite Ore ◽  
Hsc Chemistry ◽  
Sodium And Potassium

Red mud is a by-product of alumina production from bauxite ore by the Bayer method, which contains considerable amounts of valuable components such as iron, aluminum, titanium, and scandium. In this study, an approach was applied to extract iron, i.e., carbothermic reduction roasting of red mud with sodium and potassium carbonates followed by magnetic separation. The thermodynamic analysis of iron and iron-free components’ behavior during carbothermic reduction was carried out by HSC Chemistry 9.98 (Outotec, Pori, Finland) and FactSage 7.1 (Thermfact, Montreal, Canada; GTT-Technologies, Herzogenrath, Germany) software. The effects of the alkaline carbonates’ addition, as well as duration and temperature of roasting on the iron metallization degree, iron grains’ size, and magnetic separation process were investigated experimentally. The best conditions for the reduction roasting were found to be as follows: 22.01% of K2CO3 addition, 1250 °C, and 180 min of duration. As a generalization of the obtained data, the mechanism of alkaline carbonates’ influence on iron grain growth was proposed.

scholarly journals Investigating Health-Related Features and Their Impact on the Prediction of Diabetes Using Machine Learning

2021 ◽  
Vol 11 (3) ◽  
pp. 1173
Author(s):  
Hafiz Farooq Ahmad ◽  
Hamid Mukhtar ◽  
Hesham Alaqail ◽  
Mohamed Seliaman ◽  
Abdulaziz Alhumam
Keyword(s):  
Machine Learning ◽  
Risk Factors ◽  
Large Scale ◽  
Cost Effective ◽  
World Health ◽  
Evaluation Metrics ◽  
Diabetic Patients ◽  
The World ◽  
The Government ◽  
The Cost

Diabetes Mellitus (DM) is one of the most common chronic diseases leading to severe health complications that may cause death. The disease influences individuals, community, and the government due to the continuous monitoring, lifelong commitment, and the cost of treatment. The World Health Organization (WHO) considers Saudi Arabia as one of the top 10 countries in diabetes prevalence across the world. Since most of its medical services are provided by the government, the cost of the treatment in terms of hospitals and clinical visits and lab tests represents a real burden due to the large scale of the disease. The ability to predict the diabetic status of a patient with only a handful of features can allow cost-effective, rapid, and widely-available screening of diabetes, thereby lessening the health and economic burden caused by diabetes alone. The goal of this paper is to investigate the prediction of diabetic patients and compare the role of HbA1c and FPG as input features. By using five different machine learning classifiers, and using feature elimination through feature permutation and hierarchical clustering, we established good performance for accuracy, precision, recall, and F1-score of the models on the dataset implying that our data or features are not bound to specific models. In addition, the consistent performance across all the evaluation metrics indicate that there was no trade-off or penalty among the evaluation metrics. Further analysis was performed on the data to identify the risk factors and their indirect impact on diabetes classification. Our analysis presented great agreement with the risk factors of diabetes and prediabetes stated by the American Diabetes Association (ADA) and other health institutions worldwide. We conclude that by performing analysis of the disease using selected features, important factors specific to the Saudi population can be identified, whose management can result in controlling the disease. We also provide some recommendations learned from this research.

Comprehensive Utilization of Red Mud Remaining in Alumina Production

2014 ◽  
Vol 881-883 ◽  
pp. 663-666 ◽  
Author(s):  
Ao Ping He ◽  
Zhi Liu Hu ◽  
De Guang Cao ◽  
Jian Min Zeng ◽  
Bo Lin Wu ◽  
...  
Keyword(s):  
Red Mud ◽  
Aluminum Industry ◽  
Construction Materials ◽  
Environmental Restoration ◽  
Alumina Production ◽  
The Sustainable Development ◽  
Valuable Metals ◽  
High Alkalinity ◽  
Main Factors

Red mud is a solid waste which is generated in the process of alumina production and is of highly alkaline. Red mud has very complex compositions, but contains a variety of rare and valuable metals. In addition, its high alkalinity is a severe pollution to water, land, air and environment, which has been one of the main factors to affect the sustainable development of aluminum industry. The characterization of red mud, the extraction of valuable metals from red mud, the utilization of red mud in construction materials, environmental restoration materials and other fields are introduced in this paper.

scholarly journals Automated Screening System for Covid Safety

2021 ◽  
Vol 11 (2) ◽  
pp. 39-42
Author(s):  
Y Sai Subhash Reddy ◽  
◽  
Sri Krishna Borra ◽  
Koye Sai Vishnu Vamsi ◽  
Nandipati Jaswanth Sai ◽  
...  
Keyword(s):  
Continuous Monitoring ◽  
Large Scale ◽  
Raw Materials ◽  
Cost Effective ◽  
Foreseeable Future ◽  
The World ◽  
Life Threatening ◽  
Automated Screening ◽  
The Government ◽  
Optimum Solution

COVID-19 is a life-threatening virus taking the lives of thousands of people every day throughout the world. Even though many organizations and companies worked hard and developed vaccines, production of vaccines at large scale to meet today’s demand is not an easy job as there is a shortage of raw materials and cases are rising steeply. Inoculation of every individual cannot be achieved in the foreseeable future. Even the government is vaccinating people in a phased manner prioritizing older people and people who are more vulnerable to the virus. The main objective of this work is to provide an optimum solution for COVID-19 indoor safety for industries, offices, and commercial places where footfall is high. This work focus on automation of temperature sensing and mask detection which is usually carried out by a person. Elimination of human intervention reduces the risk of contraction and spreading and avoids mistakes due to human negligence. Continuous monitoring of a person is not possible and there is no guarantee that a person who is entering a place wearing a mask puts it on until he leaves it. This research intends to implement mask detection along with surveillance which is cost effective as it does not require additional hardware setup.

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