scholarly journals Potential Benefits in Copper Sulphides Liberation through Application of HRC Device in Ore Comminution Circuits

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 817 ◽  
Author(s):  
Daniel Saramak ◽  
Agnieszka Saramak
Keyword(s):  
High Pressure ◽  
Energy Savings ◽  
Environmental Influence ◽  
Dust Emission ◽  
Pressing Force ◽  
Mineral Liberation ◽  
Potential Benefits ◽  
Potential Improvement ◽  
Liberation Analysis ◽  
Grinding Kinetics

The article presents results of investigations on a high-pressure comminution process carried out in the roller press device, aiming at potential improvement of effectiveness of downstream beneficiation operations. The major point of interest of the paper concerned an assessment of the useful mineral liberation in relation to the volume of operating pressing force in the press device. Obtained results of mineral liberation were compared to flotation effects and downstream grinding process in a ball mill. Environmental influence in terms of dust emission was also analysed. The feed material was crushed in the high-pressure roller crusher (HRC) device under four different values of pressing force (Fsp): 3.0, 3.5, 4.0 and 4.5 N/mm2. Each product then underwent the liberation analysis, together with determination the energy savings through calculation of Bond’s working index, flotation recoveries and grinding kinetics. Results of investigations showed that both the most favourable crushing results and mineral liberation level were achieved for the highest values of operational pressing force. Nevertheless, the observed effects were less than linear together with further increasing of Fsp in HRC device. However, the obtained results of investigation unambiguously showed that pressing force affects the obtained crushing results: comminution degrees and flotation recoveries were higher while the duration of downstream grinding operation and grinding energy consumption were lower.

Characterisation of graphite by automated mineral liberation analysis

2014 ◽  
Vol 123 (3) ◽  
pp. 184-189 ◽  
Author(s):  
Dirk Sandmann ◽  
Sabine Haser ◽  
Jens Gutzmer
Keyword(s):  
Mineral Liberation ◽  
Liberation Analysis

New Generation of Brake Callipers to Improve Competitiveness and Energy Savings in Very High Performance Cars

2014 ◽  
Vol 217-218 ◽  
pp. 471-480
Author(s):  
Ivano Gattelli ◽  
Gian Luigi Chiarmetta ◽  
Marcello Boschini ◽  
Renzo Moschini ◽  
Mario Rosso ◽  
...  
Keyword(s):  
High Pressure ◽  
High Performance ◽  
Energy Savings ◽  
High Reliability ◽  
A357 Alloy ◽  
Bench Tests ◽  
Heat Treated ◽  
New Generation ◽  
Non Destructive ◽  
Very High

This paper concerns with the optimisation of the innovative rheocasting process to produce a new generation of brake callipers, characterised by very high reliability and strength. The attained very promising properties favoured their use on a very high performance car and the presented technique can be further extended for other important challenging applications. The prototype components are produced using T6 heat treated A357 alloy. Results on the samples machined directly from the produced callipers are in detail described and analysed. Pieces exhibiting some small defects, individuated by non-destructive tests, as well as defectless pieces have been underlined to severe industrial tests, e.g. high pressure tight, as well as severe bench tests, and it has been observed that the proposed technological process assure the fulfilment of the requirements contained in standards.

The role of maintenance in improving company's competitiveness and profitability

2014 ◽  
Vol 25 (4) ◽  
pp. 441-456 ◽  
Author(s):  
Damjan Maletič ◽  
Matjaž Maletič ◽  
Basim Al-Najjar ◽  
Boštjan Gomišček
Keyword(s):  
Gap Analysis ◽  
Research Problem ◽  
Maintenance Policy ◽  
Content Type ◽  
Potential Benefits ◽  
Points Of View ◽  
Potential Improvement ◽  
Practical Implications

Purpose – The purpose of this paper is to examine the role of maintenance in improving company's competitiveness and profitability. In the first part the paper aims to discuss the potential improvement areas from the company perspective. Second part of this paper examines maintenance impact on company's business. Design/methodology/approach – An empirical case study was utilized aiming to provide an understanding of the role of maintenance in improving company's business. The empirical data for this study were collected from a Slovenian textile company. A gap analysis was used in order to address the research problem and to identify potential improvement areas. Findings – Based on the gap analysis, the results suggest that from respondents’ points of view, maintenance practices related to condition-based maintenance approach represent the highest opportunity for improvement. The most notable empirical results of the case study showed that around 3 per cent of additional profit could be generated at weaving machine, especially if all unplanned stoppages and loss of quality due to decrease in the productivity would be prevented. Practical implications – This paper demonstrates to managers the potential benefits of maintenance policy in terms of productivity, quality and profitability. In this regard, this paper builds on a premise that company can gain higher performance benefits using more effective maintenance policy. Originality/value – The proposed conceptual model contributes to the existing literature by showing the interactions between maintenance and company's competitiveness and profitability. Empirical findings of this study therefore, acknowledge maintenance's potential of increasing the overall profit. In addition this study advances prior studies by utilizing a gap analysis which is rare in this type of research.

scholarly journals Modeling the Liberation of Comminuted Scheelite Using Mineralogical Properties

Minerals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 536 ◽  
Author(s):  
Sarbast Ahmad Hamid ◽  
Pura Alfonso ◽  
Josep Oliva ◽  
Hernan Anticoi ◽  
Eduard Guasch ◽  
...  
Keyword(s):  
Beta Distribution ◽  
Test Performance ◽  
Distribution Density ◽  
Beta Function ◽  
Size Fraction ◽  
Distribution Functions ◽  
Plant Design ◽  
Mineral Liberation ◽  
Size Grade ◽  
Liberation Analysis

In this paper, the modeling of the liberation of scheelite is presented. A pattern of concentration experiments was performed to investigate the scheelite liberation and distribution density calculation procedure. In this work, one sample from a Mittersill tungsten ore was studied. This work describes a method for determining the downstream milling energy requirements for rod mill products based on a Bond mill test performance. The grade distribution of particles at a given size fraction was calculated using a predictive liberation model. The concentration behavior of these particles in size fractions was evaluated using batch concentrate tests. The recovery of particles in size/grade classes, image analysis using mineral liberation analysis (MLA), and function calculations were implemented for the modeling of the liberation. By describing the size, grade, and recovery data of particles in size/grade classes, a technique for the measurement of distribution functions was developed that relates beta distribution, a model for the function based on the incomplete beta function, and a solution to produce liberation modeling. It was shown that the predicted results agreed well with the observed results. With a procedure for measuring the liberation, it was possible to carry out the first experimental measurement of the beta distribution. This liberation/concentrate model has wide potential applications for metallurgy and plant design, where the liberation modeling is to be determined with the distribution density solution to the predictive mineral liberation function equation, which includes the liberation of ore samples and their liberation characteristics.

scholarly journals Rare Earth Occurrences in Streams of Processing a Phosphate Ore

Minerals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 262 ◽  
Author(s):  
Xiaosheng Yang ◽  
Hannu Tapani Makkonen ◽  
Lassi Pakkanen
Keyword(s):  
Rare Earth ◽  
Sulfuric Acid ◽  
Phosphoric Acid ◽  
Rare Earth Elements ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Phosphate Ore ◽  
Mineral Liberation ◽  
Efficient Recovery ◽  
Liberation Analysis

Rare earth elements (REEs) are defined as lanthanides with Y and Sc. Rare earth occurrences including the REE-bearing phases and their distributions, measured by rare earth oxides (REOs), in the streams of processing a phosphate ore were determined by using MLA, the mineral liberation analysis and EPMA, the electron probe microanalysis. The process includes an apatite ore beneficiation by flotation and further processing of the beneficiation concentrate with sulfuric acid. Twenty-six, sixty-two and twelve percent of the total REOs (TREO) contents from the ore end up in the products of beneficiation tailings, phosphogypsum (PG) and phosphoric acid, respectively. Apatite, allanite, monazite and pyrochlore are identified as REE-bearing minerals in the beneficiation process. In the beneficiation tailings, the REEs are mainly distributed in monazite (10.3% TREO), apatite (5.9% TREO), allanite (5.4% TREO) and pyrochlore (4.3% TREO). Gypsum, monazite, apatite and other REE-bearing phases were found to host REEs in the PG and the REEs distributions are 44.9% TREO in gypsum, 15.8% TREO in monazite, 0.6% TREO in apatite and 0.6% TREO in other REE-bearing phases. Perspectives on the efficient recovery of REEs from the beneficiation tailings and the PG are discussed.

scholarly journals Influence of a High-Pressure Comminution Technology on Concentrate Yields in Copper Ore Flotation Processes

2014 ◽  
Vol 59 (3) ◽  
pp. 951-955 ◽  
Author(s):  
D. Saramak ◽  
A. Młynarczykowska ◽  
A. Krawczykowska
Keyword(s):  
High Pressure ◽  
Moisture Content ◽  
Operating Conditions ◽  
Copper Ore ◽  
Flotation Process ◽  
Pressing Force ◽  
Batch Tests ◽  
Comminution Process ◽  
The Press ◽  
Feed Moisture

Abstract The article concerns the issues of flotation process effectiveness in relationship to the operating conditions of a high-pressure comminution process course. Experimental programme covering a flotation laboratory batch tests was a verification technique of a high-pressure crushing operations course. The most favorable values of flotation concentrate weight recoveries were obtained for the pressing force 6 kN and 4% of the feed moisture. It was also determined the model of the concentrate weight recovery as a function of pressing force in the press and feed moisture content. This model was the basis for the optimization of effects of copper ore flotation processes preceded in high-pressure crushing operation in roller presses.

scholarly journals Comparison of Intracanopy Light-emitting Diode Towers and Overhead High-pressure Sodium Lamps for Supplemental Lighting of Greenhouse-grown Tomatoes

2013 ◽  
Vol 23 (1) ◽  
pp. 93-98 ◽  
Author(s):  
Celina Gómez ◽  
Robert C. Morrow ◽  
C. Michael Bourget ◽  
Gioia D. Massa ◽  
Cary A. Mitchell
Keyword(s):  
High Pressure ◽  
Energy Consumption ◽  
Energy Savings ◽  
Light Emitting Diode ◽  
Significant Proportion ◽  
Fruit Production ◽  
Light Sources ◽  
Node Number ◽  
Light Emitting ◽  
Supplemental Lighting

Electric supplemental lighting can account for a significant proportion of total greenhouse energy costs. Thus, the objectives of this study were to compare high-wire tomato (Solanum lycopersicum) production with and without supplemental lighting and to evaluate two different lighting positions + light sources [traditional high-pressure sodium (HPS) overhead lighting (OHL) lamps vs. light-emitting diode (LED) intracanopy lighting (ICL) towers] on several production and energy-consumption parameters for two commercial tomato cultivars. Results indicated that regardless of the lighting position + source, supplemental lighting induced early fruit production and increased node number, fruit number (FN), and total fruit fresh weight (FW) for both cultivars compared with unsupplemented controls for a winter-to-summer production period. Furthermore, no productivity differences were measured between the two supplemental lighting treatments. The energy-consumption metrics indicated that the electrical conversion efficiency for light-emitting intracanopy lighting (LED-ICL) into fruit biomass was 75% higher than that for HPS-OHL. Thus, the lighting cost per average fruit grown under the HPS-OHL lamps was 403% more than that of using LED-ICL towers. Although no increase in yield was measured using LED-ICL, significant energy savings for lighting occurred without compromising fruit yield.

scholarly journals Technology: A Necessary but Not Sufficient Condition for Future Personal Mobility

2018 ◽  
Vol 10 (11) ◽  
pp. 4141 ◽  
Author(s):  
Margarita Martínez-Díaz ◽  
Francesc Soriguera ◽  
Ignacio Pérez
Keyword(s):  
Autonomous Vehicles ◽  
Traffic Management ◽  
Road Traffic ◽  
Traffic Monitoring ◽  
Sustainable Mobility ◽  
Economic Interests ◽  
Personal Mobility ◽  
Technological Advances ◽  
Potential Benefits ◽  
Potential Improvement

Technological advances revolutionize industrial processes, science, communications, and our way of life. However, developed societies have reached a stage in which the fascination with technological innovations often results in their indiscriminate consumption. In this paper, road traffic is used as a line of argument to demonstrate that the random introduction of technology does not imply benefits to society. Particularly, it is analyzed why some of the potential benefits of technological progress are lost in fields such as traffic monitoring, data handling, and traffic management, or in sustainable mobility initiatives, such as the introduction of electric vehicles or the implementation vehicle sharing projects. The risks faced in the future advent of autonomous vehicles are also discussed, and ideas for improvement suggested. A critical reflection on other transportation modes that are expected to be realized in the near future is included as well. The performed analysis evidences that the potential improvement in personal mobility will not become a reality if it exclusively relies on the latest technological devices, in line with consumers’ fantasies or economic interests. This is a statement that could be generalized to many other fields. The implementation/consumption of a particular technology should not be an objective in itself, but a tool to bring benefits to society.

Experimental and Numerical Studies on Highly Loaded Supersonic Axial Turbine Cascades

2010 ◽  
Author(s):  
T. Wolf ◽  
F. Kost ◽  
E. Janke ◽  
F. Haselbach ◽  
L. Willer
Keyword(s):  
High Pressure ◽  
Mach Number ◽  
Attractive Alternative ◽  
High Pressure Turbine ◽  
Number Range ◽  
Potential Benefits ◽  
High Mach ◽  
Aero Engines ◽  
Turbine Airfoils ◽  
Highly Loaded

For the small to medium thrust range of modern aero engines, highly loaded single stage HP turbines facilitate an attractive alternative to a more conventional 2-stage HPT architecture. Whereas the potential benefits of reductions in component length and part count, hence, in weight and cost do motivate their application, the related risks are in maintaining associated losses of supersonic flows at low values as well as managing the interaction losses between HPT and the downstream sub-component to arrive at competitive levels of component efficiencies. This paper focuses on fundamental aerodynamic concept studies and related cascade experiments in support of a future highly loaded high-pressure turbine architecture. Starting with some general remarks on low-loss supersonic aerodynamic concepts for high-pressure turbines, results from development efforts towards 2D airfoil concepts viable for high-pressure turbine airfoils are shown. In particular, CFD based design approaches are compared against experimental data taken at DLR Go¨ttingen in un-cooled cascade tests and at engine representative levels of Mach and Reynolds numbers. For the airfoils investigated, it turns out that there is indeed a supersonic Mach number range were loss levels are comparable to high Mach number subsonic values, thereby enabling a competitive aerodynamic design concept for a 3D high-pressure turbine stage.

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