| 1. |
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| 2. |
- Yang, Qixing, et al.
(author)
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Erosion of referactory during gas injection : a cavitation based model
- 1989
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In: Scaninject V. - : MEFOS. ; , s. 259-289
-
Conference paper (peer-reviewed)abstract
- The problem of tuyere refractory wear has been studied in an air--water model using a 4 mm diamter tuyere. Erosion tests, with boric acid (H sub 3 BO sub 3 ) disks as refactory simulators, and measurements of back-attack frequency were carried out. The erosion pattern shows two distinct features: isolated elliptical pits and a continuous irregular shear wear pattern. The influence on these features of the surface hardness and gas flow rate was investigated. 24 ref.--
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| 3. |
- Antti, Britt-Marie, et al.
(author)
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Pulp chemistry in calcite flotation. : Modelling of oleate adsorption using theoretical equilibrium calculations
- 1989
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In: Mining engineering. - 0026-5187. ; 2:1, s. 93-109
-
Journal article (peer-reviewed)abstract
- This paper considers the conditions required for direct flotation of calcite. Flotation experiments have been performed with oleate as the collector reagent and water glass as the dispersant and modifier. To be able to explain what happens in the flotation, solubility and adsorption experiments have been conducted parallel to, and under the same conditions as, the flotation experiments. Theoretical equilibrium calculations have been made with the help of data from the practical experiments for the purpose of modelling the adsorption experiments. With theoretical equilibrium calculations it is possible to predict that silicate ions will form complexes with calcium ions at the mineral surface.
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| 4. |
- Antti, Britt-Marie, et al.
(author)
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Pulp chemistry in industrial mineral flotation. Studies of surface complex on calcite and apatite surfaces using FTIR spectroscopy
- 1989
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In: Mining engineering. - : Elsevier BV. - 0026-5187. ; 2:2, s. 217-227
-
Journal article (peer-reviewed)abstract
- Flotation experiments in a Hallimond tube have been performed on calcite and apatite at pH levels and oleate concentrations judged to be interesting from the point of view of adsorption isotherms. For the calcite system, adsorption isotherms indicate precipitation of calcium oleate after monolayer formation at pH 9, 10 and 11. In the apatite system, a double layer of oleate is formed. This means that apatite, unlike calcite, is sensitive to collector reagent overdosage. With the aid of FTIR techniques it is possible to demonstrate the existence of a surface complex in the apatite system with a calcium-oleate ratio of 1:1 at monolayer coverage of the surface. In conditions corresponding to bulk precipitation of calcium oleate, this compound can be detected by FTIR analysis of unfloated material.
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| 5. |
- Antti, Britt-Marie
(author)
-
Pulpkemi och kalcitflotation
- 1986
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In: Workshop i mineralteknik. - : MinFo. ; , s. 81-104
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Conference paper (other academic/artistic)
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| 6. |
- Banda, H., et al.
(author)
-
Der Einfluss von Trübedichte, Körnung und Filtrationsdruck auf den Durchflusswiderstand eines Filterkuchens
- 1987
-
In: Aufbereitungstechnik - Mineral processing. - 0004-783X. ; 28:9, s. 513-520
-
Journal article (peer-reviewed)abstract
- The effects of slurry concentration, filtration pressure and particle size distribution on the resistance of a filter cake are studied, and an attempt is made to examine the filtration process with reference to the structure of the filter cake. Micrographic analysis clearly demonstrates the effect of particles segregation on filtration rate. The resistance of the cake rises with increasing solids concentration of the slurry, mainly due to a lower degree of particle segregation.
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| 7. |
- Banda, H., et al.
(author)
-
Porositätsvariationen bei auf horizontalen Flächen unter Druck geformten Filterkuchen
- 1988
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In: Aufbereitungstechnik - Mineral processing. - 0004-783X. ; 29:1, s. 1-7
-
Journal article (peer-reviewed)abstract
- Direct measurement of the porosity variation in filter cakes by image analysis has been tested on chalcopyrite and magnetite slurries. It was found to give more accurate results than previous indirect methods, especially at the surface of the cake. Microscopy and image analysis visualize the effect of particle size, particle segregation and air bubbles on cake porosity. In a filter cake formed under constant pressure, the maximum porosity is shown to occur in regions inside the cake, rather than on the surface.
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| 8. |
- Banda, H., et al.
(author)
-
Strukturanalyse eines Filterkuchens mit dem Bildanalysator
- 1987
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In: Aufbereitungstechnik - Mineral processing. - 0004-783X. ; 28:4, s. 175-180
-
Journal article (peer-reviewed)abstract
- Two methods for the consolidation of filter cakes are developed; one of them is based on acrylate plastic as an impregnating medium, and the other uses epoxy resin and is suitable for sulfide-carrying materials, where the first one fails. Even cakes formed from fine particles ( less than 38 mu m) can be consolidated using these methods. Specimens prepared with acrylate offer no difficulties in grinding and polishing; those prepared with epoxy resin, however, call for procedures with bonded grinding media, and the sections are preferably examined under a scanning electron microscope. Direct comparison between the consolidation methods has not been made. Porosity and pore size distribution are measured in filter cakes formed from two different materials using a computerized image analyzer.
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| 9. |
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| 10. |
- Banda, S.M. Herath
(author)
-
Pressure filtration
- 1986
-
In: Workshop i mineralteknik. - : MinFo. ; , s. 45-61
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Conference paper (other academic/artistic)
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| 11. |
- Banda, S.M.Herath, et al.
(author)
-
Pressure filtration of a fine-grained chalcopyrite concentrate
- 1988
-
In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 17:2, s. 61-66
-
Journal article (peer-reviewed)abstract
- How material properties, cake characteristics and operating parameters affect the filtration rate and the final moisture content was investigated by laboratory test with a concentrate from a complex sulfide ore. Porosity and pore size distribution were measured by automatic image analysis. With optimum conditions, a moisture content of 5. 5% was achieved. A copper/lead concentrate floated from a complex sulfide ore at the Stekenjokk concentrator of Boliden Mineral AB, Sweden was used.
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| 12. |
- Banda, S.M.Herath, et al.
(author)
-
Structure variation in filter cakes from flocculated slurries
- 1988
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In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 17:2, s. 57-60
-
Journal article (peer-reviewed)abstract
- To flocculate slimy material dispersed in water is a common operation in mineral processing either to recover the material or to clear the water. In laboratory tests with flocculated slurries, floc sizes, porosity and sizes of filter cakes were measured by automatic image analysis. An observed decrease in filtrate flow rate at flocculant overdosage was not caused by a smaller mean floc size but may have been due to an obstruction of the pore channels by adsorbed polymer threads. Samples of a copper/lead concentrate floated at the Stekenjokk concentrator of Boliden Mineral AB, Sweden, were used for this investigation.
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| 13. |
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| 14. |
- Barbaro, F. J., et al.
(author)
-
Formation of acicular ferrite at oxide particles in steels
- 1989
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In: Materials Science and Technology. - : Informa UK Limited. - 0267-0836 .- 1743-2847. ; 5:11, s. 1057-1068
-
Journal article (peer-reviewed)abstract
- Experimental steels similar in composition to structural grades were prepared from weld metal deposits to study the formation of acicular ferrite under conditions experienced in the heat affected zone for a range of welding processes. The formation of acicular ferrite under these conditions is found to be dependent on the presence of a suitable distribution of oxide inclusions > 0·4 μm in size. The characteristics and proportion of acicular ferrite in the microstructure also depend on the prior austenite grain size and cooling rate. The relationship between these factors is presented in a simplified quantitative model, which is supported by data from limited welding trials. Metallographic observations suggest that acicular ferrite forms in two stages. The first involves the formation of relatively large primary acicular ferrite plates by multiple nucleation at intragranular inclusion sites, and the second involves the formation of many smaller acicular ferrite grains that grow sympathetically from the primary plates.
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| 15. |
- Berglund, Gun, et al.
(author)
-
Influence of different gases in flotation of sulphide minerals
- 1989
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In: Advances in Coal and Mineral Processing Using Flotation. - Littleton, Colo : Society for Mining, Metalurgy and Exploration. - 0873350871 ; , s. 71-76
-
Conference paper (peer-reviewed)abstract
- Sulfide mineral flotation is known to be affected by oxidation-reduction conditions in the pulp, although there is some doubt as to whether it is the oxidizing environment or the type of oxidant which influences flotation. Variations in the oxidizing conditions of the pulp and their subsequent effect on flotation were examined for two types of natural sulphide ore, a galena-sphalerite ore and a complex pyrite ore. Different gas mixtures ranging from pure nitrogen to pure oxygen were used to control the oxidizing conditions. Zinc recovery increased with a more oxidizing environment, and nitrogen gas acted almost as a depressant for sphalerite in the flotation of the Pb-Zn ore. For the complex pyrite ore, the selectivity between chalcopyrite and both gangue and pyrite improved when the environment was oxidizing, resulting in higher Cu recovery in the copper rougher concentrate.
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| 16. |
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| 17. |
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Björkman, Bo, et al.
(author)
-
A Quantitative Comparison of the Impurity Capacity in Some Copper Making Routes
- 1989
-
In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 18:1, s. 2-11
-
Journal article (peer-reviewed)abstract
- A metallurgical comparison of alternatives to increase the capacity to treat contaminated raw materials was made. The comparison was made by calculating the material balances at different Cu contents in mattes during Cu making and considering the effects of removal of impure intermediate products like dusts and slag for separate treatment. The most efficient methods included the removal of dust from the smelting furnace and the avoidance of reducing conditions in the matte smelting operation. By separating dust and slag produced in the Cu converters, an improved capacity could also be obtained. The removal of impurities made it possible to significantly increase the use of contaminated raw materials but, to drastically increase the impurity capacity, the introduction of pretreatment processes like roasting or leaching was necessary.
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| 22. |
- Björkman, Bo, et al.
(author)
-
New thermodynamic tools
- 1986
-
In: Scaninject IV. - Luleå : MEFOS.
-
Conference paper (peer-reviewed)
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| 23. |
- Björkman, Bo
(author)
-
Thermodynamic modelling
- 1988
-
In: Technological advances in metallurgy. - Luleå : MEFOS.
-
Conference paper (peer-reviewed)
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| 24. |
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| 25. |
- Bolin, Nils Johan
(author)
-
Flotation : en studie i några förutsättningar för selektiv flotation
- 1983
-
Doctoral thesis (other academic/artistic)abstract
- The zeta potential for oxide- and silicate minerals has been measured in different pulp liquids and a comparison has been made concerning the results of the flotation. The results show that the surface charge of the mineral particles reflect the condition of the dispersion of the pulp, and guiding the surface charge is a way of increasing the selectivity when concentrating by flotation. The results also show that the zeta potential indicates how easily amino reagents are adsorbed on silicate minerals. A successful dispersion is a condition for good selectivity with the exception of selective flocculation. Selective flocculation can be used in flotation in a case of for example quartz flotation with amine as the collector, the iron mineral being flocculated with dextrin. An example is given of selective flocculation of baryte and flotation of baryte.
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| 26. |
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| 27. |
- Bolin, Nils Johan
(author)
-
Study of muscovite flotation from a pegmatite ore
- 1983
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In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 12:3, s. 117-120
-
Journal article (peer-reviewed)abstract
- The article shows the relationship between the iron ion content of the flotation pulp and the selectivity of mica flotation of a granitic pegmatite from Limbergsbo, Sweden which contains 40% albite, 20% microcline, 30-35% quartz and 4% muscovite. The results of comparative experiments involving flotation in stainless steel and iron-rich environments show that selectivity with respect to microcline and quartz is better when an iron mill is used for grinding.
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| 28. |
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| 29. |
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| 30. |
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| 31. |
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| 32. |
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| 33. |
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| 34. |
- Forssberg, Eric, et al.
(author)
-
3D behaviour of the parameters affecting grinding in a batch ball mill
- 1986
-
In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 15:1, s. 53-58
-
Journal article (peer-reviewed)abstract
- To obtain an extensive understanding of the behavior of the key parameters in grinding processes, factorial design is applied to a ball mill test using four variables, each at three levels. This required a total of 27 tests. The influence of charge volume, mill speed, feed and pulp density on grinding fineness and net energy consumption were related and in order by multiple regression analysis. The computer-based response surfaces of the dependent variables demonstrated the combined effects of the operational parameters. They also provided a base for further tests on the multiple influence of the process variables on continuous grinding.
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| 35. |
- Forssberg, Eric, et al.
(author)
-
Adsorption of heavy metal ions on pyrrhotite
- 1981
-
In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 10:5, s. 225-230
-
Journal article (peer-reviewed)abstract
- Relatively large amounts of heay metal ions can be adsorbed on synthetic and natural pyrrhotite. The best result was obtained with Cu ions and pyrrhotite from Viscaria, with an adsorption of 4. 95 g Cu per kilogram of pyrrhotite. Good results have also been obtained with zinc and lead ions. A strongly oxidizing environment can have an adverse effect.
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| 36. |
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| 37. |
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| 38. |
- Forssberg, Eric, et al.
(author)
-
Comparative pilot scale tests with wet high intensity magnetic separators
- 1982
-
In: Erzmetall. - 0044-2658. ; 35:6, s. 285-293
-
Journal article (peer-reviewed)abstract
- The machines concerned were a Jones P71, a Boxmag-Rapid SHW 1 (since redesigned), a Readings 16-pole, a Krupp-Sol 24/14 and a Sala HGMS Mk II. The material used for test purposes was a mixture of hematite and quartzite, ground to a particle size distribution smaller than 500 mu m. The Fe assay of the material was 43. 7%. The variations in results due to capacity, magnetic field, energy consumption, matrix geometry and water consumption are reported.
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| 39. |
- Forssberg, Eric, et al.
(author)
-
Computer-assisted calculations of thermodynamic equilibria in the chalcopyrite-ethyl xanthate system
- 1984
-
In: Reagents in the Minerals Industry. - London : The Institution of Mining and Metallurgy. - 0900488786 ; , s. 251-264
-
Conference paper (other academic/artistic)abstract
- Calculations show that thermodynamic data can be used to construct pulp chemistry models that satisfactorily describe events in mineral pulps. The usefulness of such models can be enhanced by the insertion of kinetic restrictions derived from analyses of mineral pulps from commercial-scale operations. A number of interesting findings concerning the chalcopyrite-ethyl xanthate system are demonstrated. As it is possible to calculate an operating line for any given flotation system, the calculation results can be compared at all times with practical experience and measurements of flotation processes.
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| 40. |
- Forssberg, Eric, et al.
(author)
-
Dynamic flow characteristics of thin films
- 1985
-
In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 14:4, s. 163-174
-
Journal article (peer-reviewed)abstract
- Viscosity is generally cited as a chief cause for any decrease in efficiency noticed in concentration processes, particularly with undeslimed feeds, despite the fact that there is little conclusive information available on the importance of viscosity. The literature on viscosity as applied to gravity processes is critically reviewed. The dynamic flow characteristics of natural slimes containing a large amount of ultra-fine particles-exclusively clay is studied at different slime concentrations and pH. Except for some tendency to gel at low pH with low rates of shear, they behave almost as Newtonian fluids with extremely low apparant viscosities even with about 55 %-5 mu m clayey matter. At intermediate concentrations suspensions show strong gelling behavior and pH effects become pronounced. At rates of shear on concentrating equipment, pH influence becomes less significant and apparent viscosity drops greatly. A mathematical analysis of dynamic flow characteristics of thin films is made as a function of distance from the surface of the deck. The viscosity effect due to ultra-fine particles is negligible under conditions prevailing in slime gravity processes.
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| 41. |
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| 42. |
- Forssberg, Eric, et al.
(author)
-
Entphosphorung von hochphosphorhaltigen Eisenerzen durch saure Laugung
- 1981
-
In: Erzmetall. - 0044-2658. ; 34:6, s. 316-322
-
Journal article (peer-reviewed)abstract
- High phosphorous sinter fines are leached with hydrochloric or nitric acids to digest the phosphorous bearing apatite. Concentrates with less than 0. 05% P can be manufactured with acceptable losses of iron and acid consumption. The process will be viable if the phosphorus in the acid can be recovered as phosphoric acid.
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| 43. |
- Forssberg, Eric, et al.
(author)
-
Feinmahlung und Klassierung von Kalkstein für die Papierindustrie
- 1988
-
In: Freiberger Forschungshefte. A. - 0071-9390. ; :778, s. 90-101
-
Journal article (peer-reviewed)abstract
- Tests with different mills were performed to grind limestone and dolomite to particle sizes which can be used for filling and coating materials. Different vibrating ball mills, mills of co-ball-type and an attrition mill were used. Vibrating ball mills produce products with the most narrow particle size distribution. The attrition mill yielded the highest specific surface area.
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| 44. |
- Forssberg, Eric, et al.
(author)
-
Finmalning av industrimineral
- 1985
-
In: Seminarium i mineralteknik i Luleå 6-8 februari 1985. - Stockholm : MinFo. ; , s. 183-204
-
Reports (other academic/artistic)
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| 45. |
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| 46. |
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| 47. |
- Forssberg, Eric, et al.
(author)
-
Influence of different grinding methods on floatability
- 1988
-
In: International Journal of Mineral Processing. - : Elsevier BV. - 0301-7516 .- 1879-3525. ; 22:1, s. 183-192
-
Journal article (peer-reviewed)abstract
- Investigations have been in progress since the middle of 1981 to prove and explain differences in the influence of conventional and autogenous grinding on the floatability of sulphide minerals. Techniques for liberation and particle shape studies under the microscope, and measurement of pulp chemistry as to redox potential and contents of free oxygen and various sulphur-carrying ions were tested on samples from batch tests, pilot plant runs and commercial practice. The phenomena observed can partly be explained in terms of liberation and chemical characteristics of the pulp.
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| 48. |
- Forssberg, Eric, et al.
(author)
-
Liberation modelling of base metal ores in autogenous grinding
- 1985
-
In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 14:1, s. 9-17
-
Journal article (peer-reviewed)abstract
- According to a mathematical model, each mineral has its own liberation-energy characteristic curve which can be plotted. The relations between liberation, mill speed and charge volume are also presented.
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| 49. |
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| 50. |
- Forssberg, Eric, et al.
(author)
-
Phosphate bonded fused alumina abrasive resistant material
- 1980
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In: Scandinavian journal of metallurgy. - 0371-0459 .- 1600-0692. ; 9:5, s. 211-215
-
Journal article (peer-reviewed)abstract
- Suitable particle size distribution and proportion of binder phase have been determined by measurements of mechanical strength and abrasion tests. A pump impeller was made. Comparative abrasion tests have shown that the abrasion resistance is better than that of a cast iron impeller and comparable to that of a rubber impeller.
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