Extraction of Al from Coarse Al–Si Alloy by the Selective Liquation Method
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A Review of Flotation Separation of Mg Carbonates (Dolomite and Magnesite)
minerals Review A Review of Flotation Separation of Mg Carbonates (Dolomite and Magnesite) Darius G. Wonyen 1,†, Varney Kromah 1,†, Borbor Gibson 1,† ID , Solomon Nah 1,† and Saeed Chehreh Chelgani 1,2,* ID 1 Department of Geology and Mining Engineering, Faculty of Engineering, University of Liberia, P.O. Box 9020 Monrovia, Liberia; [email protected] (D.G.W.); [email protected] (Y.K.); [email protected] (B.G.); [email protected] (S.N.) 2 Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI 48109, USA * Correspondence: [email protected]; Tel.: +1-41-6830-9356 † These authors contributed equally to the study. Received: 24 July 2018; Accepted: 13 August 2018; Published: 15 August 2018 Abstract: It is well documented that flotation has high economic viability for the beneficiation of valuable minerals when their main ore bodies contain magnesium (Mg) carbonates such as dolomite and magnesite. Flotation separation of Mg carbonates from their associated valuable minerals (AVMs) presents several challenges, and Mg carbonates have high levels of adverse effects on separation efficiency. These complexities can be attributed to various reasons: Mg carbonates are naturally hydrophilic, soluble, and exhibit similar surface characteristics as their AVMs. This study presents a compilation of various parameters, including zeta potential, pH, particle size, reagents (collectors, depressant, and modifiers), and bio-flotation, which were examined in several investigations into separating Mg carbonates from their AVMs by froth flotation. Keywords: dolomite; magnesite; flotation; bio-flotation 1. Introduction Magnesium (Mg) carbonates (salt-type minerals) are typical gangue phases associated with several valuable minerals, and have complicated processing [1,2]. -
Calcination) 2
Thermal Treatment of Catalysts Modern Methods in Heterogeneous Catalysis Research Friederike C. Jentoft, October 31, 2003 Outline 1. Terminology (calcination) 2. Sample vs. oven set temperature 3. Self-generated atmosphere & self-steaming of zeolites 4. Combustion 5. Glow phenomenon & zirconia catalysts 6. Crystallization 7. Loss of surface area 8. Effect of additives 9. Solid-solid wetting 10.Reductive treatments & SMSI Steps of Catalyst Preparation v IUPAC defines 3 steps of catalyst preparation 1. Preparation of primary solid, associating all the useful compounds 2. Processing of that primary solid to obtain the catalyst precursor for example by heat treatment 3. Activation of the precursor to give the active catalyst (reduction to metal, formation of sulfides, deammoniation of zeolites) Heat Treatment of Intermediate Solids or Precursors v drying v thermal decomposition of salts (nitrates, ammonium salts) v calcination v product is a "reasonably inert solid" which can be stored easily Annealing v in a general meaning: a heating of a material over a long time span; strain and cracks in a crystalline solid can be removed Origin of the Term "Calcination" v latin "calx" = playstone limestone, (greek chálix) v burning of calcium carbonate (limestone) to calcium oxide (quicklime) -1 CaCO3 → CaO + CO2 ΔH(900°C)=3010 kJ mol v used to construct Giza pyramids (ca. 2800 A.C.), burning of limestone ("Kalkbrennen") mentioned by Cato 184 A.C. v performed in kilns (ovens) at 900°C v addition of air to sustain combustion + cool product Examples for -
Petrology of Ore Deposits
Petrology of Ore Deposits An Introduction to Economic Geology Introductory Definitions Ore: a metalliferous mineral, or aggregate mixed with gangue that can me mined for a profit Gangue: associated minerals in ore deposit that have little or no value. Protore: initial non-economic concentration of metalliferous minerals that may be economic if altered by weathering (Supergene enrichment) or hydrothermal alteration Economic Considerations Grade: the concentration of a metal in an ore body is usually expressed as a weight % or ppm. The process of determining the grade is termed “assaying” Cut-off grade: after all economic and political considerations are weighed this is the lowest permissible grade that will mined. This may change over time. Example Economic Trends Economy of Scale As ore deposits are mined the high-grade zones are developed first leaving low-grade ores for the future with hopefully better technology Since mining proceeds to progressively lower grades the scale of mining increases because the amount of tonnage processed increases to remove the same amount of metal Outputs of 40,000 metric tons per day are not uncommon Near-surface open pit mines are inherently cheaper than underground mines Other factors important to mining costs include transportation, labor, power, equipment and taxation costs Classification of Ore bodies Proved ore: ore body is so thoroughly studied and understood that we can be certain of its geometry, average grade, tonnage yield, etc. Probable ore: ore body is somewhat delineated by surface mapping and some drilling. The geologists is reasonably sure of geometry and average grade. Possible Ore: outside exploration zones the geologist may speculate that the body extends some distance outside the probable zone but this is not supported by direct mapping or drilling. -
2017 Annual Report 1 Definitions
* Bank of Jinzhou Co., Ltd. is not an authorized institution within the meaning of the Banking Ordinane (Chapter 155 of the Laws of Hong Kong), not subject to the supervision of the Hong Kong Monetary Authority, and not authorized to carry on banking and/or deposit-taking business in Hong Kong. Contents 2 Definitions 4 Chapter 1 Company Profile 7 Chapter 2 Financial Highlights 10 Chapter 3 Chairman ’s Statement 12 Chapter 4 President’s Statement 14 Chapter 5 Management Discussion and Analysis 71 Chapter 6 Changes in Ordinary Shares and Particulars of Shareholders 77 Chapter 7 Particulars of Preference Shares 79 Chapter 8 Directors, Supervisors, Senior Management, Employees and Organizations 98 Chapter 9 Corporate Governance Report 119 Chapter 10 Directors’ Report 127 Chapter 11 Supervisors’ Report 130 Chapter 12 Social Responsibility Report 132 Chapter 13 Internal Control and Internal Audit 136 Chapter 14 Important Events 139 Chapter 15 Independent Auditor’s Report 149 Chapter 16 Financial Statements 269 Chapter 17 Unaudited Supplementary Financial Information Bank of Jinzhou Co., Ltd. 2017 Annual Report 1 Definitions In this annual report, unless the context otherwise requires, the following terms shall have the meanings set out below: “A Share Offering” the Bank’s proposed initial public offering of not more than 1,927,000,000 A shares, which has been approved by the Shareholders on 29 June 2016 “Articles of Association” the articles of association of the Bank, as the same may be amended from time to time “the Bank”, “Bank of Jinzhou” -
Evaluation of City Sustainability from the Perspective of Behavioral Guidance
sustainability Article Evaluation of City Sustainability from the Perspective of Behavioral Guidance Ying Zhou 1,*, Weiwei Li 2 , Pingtao Yi 2 and Chengju Gong 3 1 School of Management, Shenyang Jianzhu University, Shenyang 110168, China 2 School of Business Administration, Northeastern University, Shenyang 110168, China; [email protected] (W.L.); [email protected] (P.Y.) 3 School of Economics and Management, Harbin Engineering University, Harbin 150001, China; [email protected] * Correspondence: [email protected] Received: 8 November 2019; Accepted: 28 November 2019; Published: 30 November 2019 Abstract: High-quality evaluation of city sustainability is an important part of city policy making and development. In this paper, we evaluated the sustainability of the 14 cities in Liaoning, China, from 2015 to 2017. Based on the comprehensive consideration of the interactions among the social, economic and environmental systems, the traditional evaluation indicator system is refined. We incorporate the attitude of decision makers into the evaluation model and propose an objective weighting method by considering data distribution to objectively guide the cities to develop towards the established goals. The empirical research results show that cities located in eastern Liaoning performed the best and in western Liaoning performed the worst. The performances of the 14 cities in Liaoning were not perfect. Both the evaluation values and growth rates of 7 cities (accounting for 50.00%) were lower than the overall average level. The evaluation values of the three systems of the 14 cities were not balanced. The evaluation values of the social, economic and environmental systems fluctuated within the range of [0.0159, 0.0346], [0.0151, 0.0677] and [0.0123, 0.0483], respectively. -
Principles of Extractive Metallurgy Lectures Note
PRINCIPLES OF EXTRACTIVE METALLURGY B.TECH, 3RD SEMESTER LECTURES NOTE BY SAGAR NAYAK DR. KALI CHARAN SABAT DEPARTMENT OF METALLURGICAL AND MATERIALS ENGINEERING PARALA MAHARAJA ENGINEERING COLLEGE, BERHAMPUR DISCLAIMER This document does not claim any originality and cannot be used as a substitute for prescribed textbooks. The information presented here is merely a collection by the author for their respective teaching assignments as an additional tool for the teaching-learning process. Various sources as mentioned at the reference of the document as well as freely available material from internet were consulted for preparing this document. The ownership of the information lies with the respective author or institutions. Further, this document is not intended to be used for commercial purpose and the faculty is not accountable for any issues, legal or otherwise, arising out of use of this document. The committee faculty members make no representations or warranties with respect to the accuracy or completeness of the contents of this document and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. BPUT SYLLABUS PRINCIPLES OF EXTRACTIVE METALLURGY (3-1-0) MODULE I (14 HOURS) Unit processes in Pyro metallurgy: Calcination and roasting, sintering, smelting, converting, reduction, smelting-reduction, Metallothermic and hydrogen reduction; distillation and other physical and chemical refining methods: Fire refining, Zone refining, Liquation and Cupellation. Small problems related to pyro metallurgy. MODULE II (14 HOURS) Unit processes in Hydrometallurgy: Leaching practice: In situ leaching, Dump and heap leaching, Percolation leaching, Agitation leaching, Purification of leach liquor, Kinetics of Leaching; Bio- leaching: Recovery of metals from Leach liquor by Solvent Extraction, Ion exchange , Precipitation and Cementation process. -
Profits from the Past
Reprocessing and tailings reduction.qxp_proof 29/04/2020 09:50 Page 1 REPROCESSING AND TAILINGS REDUCTION In Colombia, AuVert's technology is being combined with CDE's experience in dewatering Profits from the past and tailings management to extract the remaining precious metals existing in the ground, while removing up to 93% of residual mercury which has to date prevented this land from being used by the local population reasons why mining companies may be cautious about using tailings as backfill material or relocating current day ‘waste’ to an inaccessible area of the mine, according to Gerritsen. “As technology improves, the opportunity to recover more of the metals/minerals increases,” he said. “There are elements where that may not be the case – coal ash, for example, cannot be reprocessed but can be used to produce cement. While tailings dam liabilities and falling water resources are There are certainly opportunities with gold, affecting the ability of miners to start new mines, or expand copper and even coal, for instance.” The strategies companies ultimately pursue for existing ones, these issues are strengthening the case for these ‘waste streams’ depend on the technology reprocessing and retreating ‘waste’ sites or streams. Dan available and the safety of the facilities, Gerritsen Gleeson explores an increasingly diverse market focused on remarked. revenue generation and risk reduction “For instance, it may not be economically viable to reprocess the material currently in a ith improved transparency around recycling and thickening, or SART, plant from BQE tailings storage facility and, therefore, the owner tailings dams and waste stockpiles now Water will only bolster cash reserves through the may decide to close it or put it into a non-active Wpart and parcel of being a responsible recovery of a high-grade saleable copper sulphide state,” he said. -
Table of Contents
Table of Contents Preface ........................................... xi Chapter 1. Physical Extraction Operations .................... 1 1.1. Solid-solid and solid-fluid separation operations .............. 1 1.1.1. Flotation ................................... 1 1.1.2. Settling under gravity ........................... 3 1.1.3. Centrifugation ................................ 3 1.1.4. Filtration ................................... 4 1.2. Separation operations of the components of a fluid phase ........ 5 1.2.1. Condensation ................................ 5 1.2.2. Vacuum distillation ............................. 5 1.2.3. Liquation ................................... 6 1.2.4. Distillation .................................. 8 1.2.5. Extractive distillation ........................... 11 1.3. Bibliography ................................... 12 Chapter 2. Hydrometallurgical Operations .................... 15 2.1. Leaching and precipitation operations .................... 15 2.1.1. Leaching and precipitation reactors ................... 15 2.1.2. Continuous stirred tank reactor (CSTR) ................ 18 2.1.3. Models of leaching and precipitation operations ........... 20 2.1.4. Particle-size distribution (PSD) functions ............... 21 2.2. Reactor models based on particle residence time distribution functions ........................................ 24 2.2.1. Performance equations for a single CSTR ............... 24 2.2.2. Performance equations for multistage CSTRs ............. 28 2.3. Reactor models based on the population balance -
Calcium-Looping Performance of Steel and Blast Furnace Slags for Thermochemical Energy Storage in Concentrated Solar Power Plants
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by idUS. Depósito de Investigación Universidad de Sevilla Calcium-Looping performance of steel and blast furnace slags for Thermochemical Energy Storage in Concentrated Solar Power plants Jose Manuel Valverde a*, Juan Miranda-Pizarroa,c, Antonio Perejónb,c, Pedro E. Sánchez-Jiménezc, Luis A. Pérez-Maquedac aFacultad de Fisica, Universidad de Sevilla, Avenida Reina Mercedes s/n, 41012 Sevilla, Spain. bDepartamento de Química Inorgánica, Facultad de Química, Universidad de Sevilla, C. Prof. García González 1, Sevilla 41071, Spain. cInstituto de Ciencia de Materiales de Sevilla (C.S.I.C. - Universidad de Sevilla). C. Américo Vespucio 49, Sevilla 41092, Spain. Abstract The Calcium Looping (CaL) process, based on the carbonation/calcination of CaO, has been proposed as a feasible technology for Thermochemical Energy Storage (TCES) in Concentrated Solar Power (CSP) plants. The CaL process usually employs limestone as CaO precursor for its very low cost, non-toxicity, abundance and wide geographical distribution. However, the multicycle activity of limestone derived CaO under relevant CaL conditions for TCES in CSP plants can be severely limited by pore plugging. In this work, the alternative use of calcium-rich steel and blast furnace slags after treatment with acetic acid is investigated. A main observation is that the calcination temperature to regenerate the CaO is significantly reduced as compared to limestone. Furthermore, the multicycle activity of some of the slags tested at relevant CaL conditions for TCES remains high and stable if the treated samples are subjected to filtration. This process serves to remove silica grains, which helps decrease the porosity of the CaO resulting from calcination thus mitigating pore plugging. -
A History of Tailings1
A HISTORY OF MINERAL CONCENTRATION: A HISTORY OF TAILINGS1 by Timothy c. Richmond2 Abstract: The extraction of mineral values from the earth for beneficial use has been a human activity- since long before recorded history. Methodologies were little changed until the late 19th century. The nearly simultaneous developments of a method to produce steel of a uniform carbon content and the means to generate electrical power gave man the ability to process huge volumes of ores of ever decreasing purity. The tailings or waste products of mineral processing were traditionally discharged into adjacent streams, lakes, the sea or in piles on dry land. Their confinement apparently began in the early 20th century as a means for possible future mineral recovery, for the recycling of water in arid regions and/or in response to growing concerns for water pollution control. Additional Key Words: Mineral Beneficiation " ... for since Nature usually creates metals in an impure state, mixed with earth, stones, and solidified juices, it is necessary to separate most of these impurities from the ores as far as can be, and therefore I will now describe the methods by which the ores are sorted, broken with hammers, burnt, crushed with stamps, ground into powder, sifted, washed ..•. " Agricola, 1550 Introduction identifying mining wastes. It is frequently used mistakenly The term "tailings" is to identify all mineral wastes often misapplied when including the piles of waste rock located at the mouth of 1Presented at the 1.991. National mine shafts and adi ts, over- American. Society for Surface burden materials removed in Mining and Reclamation Meeting surface mining, wastes from in Durango, co, May 1.4-17, 1.991 concentrating activities and sometimes the wastes from 2Timothy c. -
World Bank Document
The World Bank Report No: ISR8824 Implementation Status & Results China China-Second Liaoning Medium Cities Infrastructure Project (P092618) Operation Name: China-Second Liaoning Medium Cities Infrastructure Project Project Stage: Implementation Seq.No: 6 Status: ARCHIVED Archive Date: 16-May-2013 (P092618) Public Disclosure Authorized Country: China Approval FY: 2007 Product Line:IBRD/IDA Region: EAST ASIA AND PACIFIC Lending Instrument: Specific Investment Loan Implementing Agency(ies): Lioning Urban Construction and Renewal Project Office Key Dates Public Disclosure Copy Board Approval Date 26-Jun-2007 Original Closing Date 31-Dec-2013 Planned Mid Term Review Date Last Archived ISR Date 08-Apr-2012 Effectiveness Date 04-Dec-2007 Revised Closing Date 31-Dec-2013 Actual Mid Term Review Date 18-Oct-2010 Project Development Objectives China-Second Liaoning Medium Cities Infrastructure Project (P092618) Project Development Objective (from Project Appraisal Document) The project development objective is to improve the performance and sustainability of water supply, wastewater, and solid waste services in the LMC-2 cities. Enhanced wastewater and solid waste services will also help reduce pollution into the Bohai Sea and contribute to improving Bohai Sea water quality. Has the Project Development Objective been changed since Board Approval of the Program? Public Disclosure Authorized Yes No China-GEF-Liaoning (P090375) Global Environmental Objective (from Project Appraisal Document) The global environmental objective of the LMC-2 project with the GEF enhancements is the reduction of land-based pollution into the Bohai Sea through investments in wastewater and solid waste infrastructure and improved utility regulation, planning and management in the LMC-2 cities and throughout Liaoning Province. -
Occurrence and Extraction of Metals MODULE - 6 Chemistry of Elements
Occurrence and Extraction of Metals MODULE - 6 Chemistry of Elements 16 Notes OCCURRENCE AND EXTRACTION OF METALS Metals and their alloys are extensively used in our day-to-day life. They are used for making machines, railways, motor vehicles, bridges, buildings, agricultural tools, aircrafts, ships etc. Therefore, production of a variety of metals in large quantities is necessary for the economic growth of a country. Only a few metals such as gold, silver, mercury etc. occur in free state in nature. Most of the other metals, however, occur in the earth's crust in the combined form, i.e., as compounds with different anions such as oxides, sulphides, halides etc. In view of this, the study of recovery of metals from their ores is very important. In this lesson, you shall learn about some of the processes of extraction of metals from their ores, called metallurgical processes. OBJECTIVES After reading this lesson, you will be able to : z differentiate between minerals and ores; z recall the occurrence of metals in native form and in combined form as oxides, sulphides, carbonates and chlorides; z list the names and formulae of some common ores of Na, Al, Sn, Pb ,Ti, Fe, Cu, Ag and Zn; z list the occurrence of minerals of different metals in India; z list different steps involved in the extraction of metals; * An alloy is a material consisting of two or more metals, or a metal and a non-metal. For example, brass is an alloy of copper and zinc; steel is an alloy of iron and carbon.