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Tano, Kent
Publications (10 of 36) Show all publications
Jonsén, P., Pålsson, B., Stener, J., Häggblad, H.-Å., Tano, K. & Berggren, A. (2014). Development of physically based tumbling mill models (ed.). In: (Ed.), (Ed.), Proceedings of XXIII International Mineral Processing Congress: XXVII, Santiago, Chile 20-24 October 2014. Paper presented at International Mineral Processing Congress : 20/10/2014 - 24/10/2014. Santiago: IMPC
Open this publication in new window or tab >>Development of physically based tumbling mill models
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2014 (English)In: Proceedings of XXIII International Mineral Processing Congress: XXVII, Santiago, Chile 20-24 October 2014, Santiago: IMPC , 2014Conference paper, Published paper (Refereed)
Abstract [en]

Numerical modelling of grinding in tumbling mills is traditionally done with the discrete element method (DEM). The grinding balls are then represented by DEM particles and the mill structure is considered rigid. To include more physical phenomena several numerical methods can be combined. One important improvement is to include the mill structure response, using the finite element method (FEM). The interaction between charge and lining can then be studied in detail. The pulp can also be included using a particle-based continuum method e.g. smoothed particle method (SPH). The strength of SPH lies in modelling of free surface flows and very large deformations and it is suited to model simultaneous fluid and granular flow. Still, the coarse particles (grinding balls) in the charge are suitable to be model using DEM. Each of these methods has their strength and weaknesses, but combined they can successfully mimic the main features of the charge movement. With these numerical tools the complex interaction between the different components of the grinding process; pulp, charge, lining and the mechanical behaviour of the mill, can be studied together. This work will present novel numerical approaches to model, simulate and validate charge behaviour in tumbling mills. These numerical models give possibilities to better understand the physical and mechanical behaviour of particulate material systems during grinding in a tumbling mill. This is important in order to develop and optimise future high-capacity grinding circuits and save energy.

Place, publisher, year, edition, pages
Santiago: IMPC, 2014
National Category
Applied Mechanics Metallurgy and Metallic Materials
Research subject
Solid Mechanics; Mineral Processing
Identifiers
urn:nbn:se:ltu:diva-26841 (URN)018f4d03-3e2c-4a32-b5ff-06171f776a6f (Local ID)9789569393150 (ISBN)018f4d03-3e2c-4a32-b5ff-06171f776a6f (Archive number)018f4d03-3e2c-4a32-b5ff-06171f776a6f (OAI)
Conference
International Mineral Processing Congress : 20/10/2014 - 24/10/2014
Note
Godkänd; 2014; 20141117 (parj)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-04-12Bibliographically approved
Oghazi, P., Pålsson, B. & Tano, K. (2011). Classifying best access points for return of external flows into flowsheets (ed.). Paper presented at . Open Mineral Processing Journal, 4, 1-6
Open this publication in new window or tab >>Classifying best access points for return of external flows into flowsheets
2011 (English)In: Open Mineral Processing Journal, ISSN 1874-8414, E-ISSN 1874-8414, Vol. 4, p. 1-6Article in journal (Refereed) Published
Abstract [en]

External flows are process streams that come from auxiliary processes or events. They are re-routed into the ordinary flowsheet since they are thought to be too valuable to be sent to any tailings pond. External flows come from multiple sources, e.g. drainage sumps, spillage thickeners, depleted products etc. Therefore, external flows may fit or notfit into an existing flowsheet depending on several factors like, flow rate frequency, dilution ratio variation, chemical and mineralogical composition, particle size or particle morphology. By using Particle Texture Analysis to investigate external flows and compare them with existing ordinary flows it is possible to pinpoint from a process mineralogy via point to what extent the external flow fits into the ordinary processing flowsheet. Results from this information category helps to reach a higher quality of process knowledge and control for every step in the concentrator. Results show that some recycled flows reconnected to the main flow are not connected to the best point. A side effect of the analysis is that some flows may be sent to later grinding stages. Thus, decreasing the load on the primary mill, and increasing the retention time.

National Category
Metallurgy and Metallic Materials
Research subject
Mineral Processing
Identifiers
urn:nbn:se:ltu:diva-3049 (URN)10.2174/18748414001104010001 (DOI)0cd8c7d7-e86f-456c-9e7a-a52db97f97fb (Local ID)0cd8c7d7-e86f-456c-9e7a-a52db97f97fb (Archive number)0cd8c7d7-e86f-456c-9e7a-a52db97f97fb (OAI)
Note
Validerad; 2011; 20110210 (palle)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-02-28Bibliographically approved
Alatalo, J., Pålsson, B. & Tano, K. (2011). Evaluation of data from a pilot scale pebble mill (ed.). In: (Ed.), Johanna Alatalo (Ed.), Conference in minerals engineering: Luleå, 8-9 February 2011. Paper presented at Konferens i mineralteknik 2011 : 08/02/2011 - 09/02/2011. Luleå: Luleå tekniska universitet
Open this publication in new window or tab >>Evaluation of data from a pilot scale pebble mill
2011 (English)In: Conference in minerals engineering: Luleå, 8-9 February 2011 / [ed] Johanna Alatalo, Luleå: Luleå tekniska universitet, 2011Conference paper, Published paper (Other academic)
Place, publisher, year, edition, pages
Luleå: Luleå tekniska universitet, 2011
National Category
Metallurgy and Metallic Materials
Research subject
Mineral Processing
Identifiers
urn:nbn:se:ltu:diva-39542 (URN)e598c59e-16b6-4243-b8d3-062beb49c168 (Local ID)978-91-7439-220-3 (ISBN)e598c59e-16b6-4243-b8d3-062beb49c168 (Archive number)e598c59e-16b6-4243-b8d3-062beb49c168 (OAI)
Conference
Konferens i mineralteknik 2011 : 08/02/2011 - 09/02/2011
Note
Godkänd; 2011; 20110415 (andbra)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2018-02-28Bibliographically approved
Ljung, A.-L., Lundström, T. S., Marjavaara, D. & Tano, K. (2011). Influence of air humidity on drying of individual iron ore pellets (ed.). Paper presented at . Drying Technology, 29(9), 1101-1111
Open this publication in new window or tab >>Influence of air humidity on drying of individual iron ore pellets
2011 (English)In: Drying Technology, ISSN 0737-3937, E-ISSN 1532-2300, Vol. 29, no 9, p. 1101-1111Article in journal (Refereed) Published
Abstract [en]

The influence of air humidity on drying is investigated at four inlet air dew points; T dp = 273, 292, 313, and 333 K. A numerical model taking into account capillary transport of liquid and internal evaporation is applied to a spherical geometry representative for an individual iron ore pellet. Drying simulations are carried out with commercial computational fluid dynamic (CFD) software and the boundary conditions are calculated from the surrounding fluid flow. The results indicate that the effect of air humidity arises from the start of the first drying period, that is, the surface evaporation period, whereas the difference is reduced at the end of the period due to a prolonged stage of constant rate drying attained at high saturations. At low saturations, there is no constant drying stage because the surface becomes locally dry before the pellet temperature has stabilized at the wet bulb temperature. The magnitudes of the drying rates and moisture contents are rather similar at the time when internal drying becomes dominating (i.e., when the total surface evaporation rate is zero) for the respective dew points, yet the drying time is increased at high saturations. It was also found that the moisture gradients at the surface and inside the pellet increased with drying rate.

National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-8587 (URN)10.1080/07373937.2011.571355 (DOI)000294803500011 ()2-s2.0-79960217865 (Scopus ID)71be761e-7f9a-489f-8a50-82ca3de733ec (Local ID)71be761e-7f9a-489f-8a50-82ca3de733ec (Archive number)71be761e-7f9a-489f-8a50-82ca3de733ec (OAI)
Note
Validerad; 2011; 20110309 (stlu)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Jonsén, P., Pålsson, B., Häggblad, H.-Å., Tano, K. & Berggren, A. (2011). Modelling of the interaction between charge and lining in tumbling mills: Combination of numerical methods (ed.). Paper presented at Bergforsk Annual Meeting 2011 : 04/05/2011 - 05/05/2011. Paper presented at Bergforsk Annual Meeting 2011 : 04/05/2011 - 05/05/2011.
Open this publication in new window or tab >>Modelling of the interaction between charge and lining in tumbling mills: Combination of numerical methods
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2011 (English)Conference paper, Oral presentation only (Other academic)
National Category
Applied Mechanics Metallurgy and Metallic Materials
Research subject
Solid Mechanics; Mineral Processing
Identifiers
urn:nbn:se:ltu:diva-26815 (URN)010b924d-3ca6-4f56-bb7d-f539ca44bf20 (Local ID)010b924d-3ca6-4f56-bb7d-f539ca44bf20 (Archive number)010b924d-3ca6-4f56-bb7d-f539ca44bf20 (OAI)
Conference
Bergforsk Annual Meeting 2011 : 04/05/2011 - 05/05/2011
Note
Godkänd; 2011; 20110816 (ysko)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-04-12Bibliographically approved
Jonsén, P., Pålsson, B., Häggblad, H.-Å., Tano, K. & Berggren, A. (2011). Novel simulation methods for mill charges (ed.). In: (Ed.), Johanna Alatalo (Ed.), Conference in minerals engineering: Luleå, 8-9 February 2011. Paper presented at Konferens i mineralteknik 2011 : 08/02/2011 - 09/02/2011. Luleå: Luleå tekniska universitet
Open this publication in new window or tab >>Novel simulation methods for mill charges
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2011 (English)In: Conference in minerals engineering: Luleå, 8-9 February 2011 / [ed] Johanna Alatalo, Luleå: Luleå tekniska universitet, 2011Conference paper, Published paper (Other academic)
Place, publisher, year, edition, pages
Luleå: Luleå tekniska universitet, 2011
National Category
Applied Mechanics Metallurgy and Metallic Materials
Research subject
Solid Mechanics; Mineral Processing
Identifiers
urn:nbn:se:ltu:diva-40357 (URN)f7270d3d-48d9-4d9c-b3fd-eba26979f1fc (Local ID)978-91-7439-220-3 (ISBN)f7270d3d-48d9-4d9c-b3fd-eba26979f1fc (Archive number)f7270d3d-48d9-4d9c-b3fd-eba26979f1fc (OAI)
Conference
Konferens i mineralteknik 2011 : 08/02/2011 - 09/02/2011
Note
Godkänd; 2011; 20110418 (andbra)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2018-04-12Bibliographically approved
Jonsén, P., Tano, K., Pålsson, B. & Berggren, A. (2011). Prediction of mill structure behaviour in a tumbling mill (ed.). Paper presented at . Minerals Engineering, 24(3-4), 236-244
Open this publication in new window or tab >>Prediction of mill structure behaviour in a tumbling mill
2011 (English)In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 24, no 3-4, p. 236-244Article in journal (Refereed) Published
Abstract [en]

Computational demands and the lack of detailed experimental verification have limited the value of distinct element method (DEM) modelling approaches in mill simulation studies. This paper presents the results of a study in which the deflection of a lifter bar in a pilot ball mill is measured by an embedded strain gauge sensor and compared to deflections predicted from finite element (FE) simulations. The flexible rubber lifter and the lining in a tumbling mill are modelled with the finite element method (FEM) and the grinding medium is modelled with DEM. The deflection profile obtained from DEM-FE simulation shows a reasonably good correspondence to pilot mill measurements. To study the charge impact on the mill structure two different charges are used in the simulations. The approach is a contribution to the validation of DEM-FE simulations and an introduction to the description of a bendable rubber lifter implemented in a DEM-FEM mill model. It opens up the possibility to predict contact forces for varying mill dimensions and liner combinations. FEM is especially valuable in this case, since there are readily available libraries with material models.

National Category
Applied Mechanics Metallurgy and Metallic Materials
Research subject
Solid Mechanics; Mineral Processing
Identifiers
urn:nbn:se:ltu:diva-2600 (URN)10.1016/j.mineng.2010.08.012 (DOI)000289500400011 ()2-s2.0-79952535910 (Scopus ID)03bc1720-cca6-11df-a707-000ea68e967b (Local ID)03bc1720-cca6-11df-a707-000ea68e967b (Archive number)03bc1720-cca6-11df-a707-000ea68e967b (OAI)
Note
Validerad; 2011; 20100930 (ysko)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Jonsén, P., Pålsson, B., Häggblad, H.-Å., Tano, K. & Berggren, A. (2011). Simulation of charge and structure behaviour in a tumbling mill (ed.). In: (Ed.), (Ed.), 8th European LD-DYNA Users Conference May 23-24, 2011, Strasbourg: . Paper presented at European LD-DYNA Users Conference : 23/05/2011 - 24/05/2011.
Open this publication in new window or tab >>Simulation of charge and structure behaviour in a tumbling mill
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2011 (English)In: 8th European LD-DYNA Users Conference May 23-24, 2011, Strasbourg, 2011Conference paper, Published paper (Refereed)
Abstract [en]

For a long time discrete element methods (DEM) has been used as simulation tools to gain insight into particulate flow processes. The mechanical behaviour in tumbling mills is complex. To include all phenomena that occur in a single numerical model is today not possible. A common approach is to model milling charges using the DEM assuming a rigid mill structure. To close the gap between reality and numerical models in milling, more physically realistic methods have to be used. In this work, the finite element method (FEM) and the smoothed particle hydrodynamic (SPH) method are used together to model a ball mill charge in a tumbling mill. The mesh free formulation and the adaptive nature of the SPH method result in a method that handles extremely large deformations and thereby suits for modelling of grinding charges. The flexible rubber lifter and the lining are modelled with the finite element method. The mill structure consists of rubber lifter and liners and a mantel made of solid steel. For the elastic behaviour of the rubber, a Blatz-Ko hyper-elastic model is used. The supplier of the lining provided experimental data for the rubber. The deflection profile of the lifters obtained from SPH-FEM simulation shows a reasonably good correspondence to pilot mill measurements as measured by an embedded strain gauge sensor. This computational model makes it possible to predict charge pressure and shear stresses within the charge. It is also possible to predict contact forces for varying mill dimensions and liner combinations.

National Category
Applied Mechanics Metallurgy and Metallic Materials
Research subject
Solid Mechanics; Mineral Processing
Identifiers
urn:nbn:se:ltu:diva-29251 (URN)2a94fbe9-fbef-438e-b918-4f1ac99bdd97 (Local ID)2a94fbe9-fbef-438e-b918-4f1ac99bdd97 (Archive number)2a94fbe9-fbef-438e-b918-4f1ac99bdd97 (OAI)
Conference
European LD-DYNA Users Conference : 23/05/2011 - 24/05/2011
Note
Godkänd; 2011; 20110717 (parj)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-04-12Bibliographically approved
Ljung, A.-L., Lundström, S. & Tano, K. (2011). Simulation of convective drying of a cylindrical iron ore pellet (ed.). Paper presented at . International journal of numerical methods for heat & fluid flow, 21(6), 703-716
Open this publication in new window or tab >>Simulation of convective drying of a cylindrical iron ore pellet
2011 (English)In: International journal of numerical methods for heat & fluid flow, ISSN 0961-5539, E-ISSN 1758-6585, Vol. 21, no 6, p. 703-716Article in journal (Refereed) Published
Abstract [en]

Purpose – The purpose of this paper is to numerically model convective drying of a two-dimensional iron ore pellet subjected to turbulent flow.Design/methodology/approach – Simulations of the iron ore pellet drying process are carried out with commercial computational fluid dynamics software. The moisture distribution inside the pellet is calculated from a diffusion equation and drying due to evaporation at the surface is taken into account.Findings – The results show an initial warm up phase with a succeeding constant rate drying period. Constant drying rate will only be achieved if the surface temperature is constant. The falling rate period will subsequently start at the forward stagnation point when the minimum moisture content is reached, while other parts of the surface still provide enough moisture to allow surface evaporation. The phases will thus coexist for a period of time.Research limitations/implications – Owing to the complex physical processes involved in iron ore pellet drying, some parameters in the model are based on estimations. The effective diffusivity should, for example, in the future be investigated more thoroughly. It is also important to extend the model so that the falling rate drying period is also included. The model is at present undergoing further validation.Practical implications – The simulations can provide detailed information on some key fluid dynamics and physical processes that an iron ore pellet undergoes during drying.Originality/value – The simulations enhance the understanding of iron ore pellet drying and the model provides a complement to experimental investigations when optimizing the drying process.

National Category
Fluid Mechanics and Acoustics
Research subject
Fluid Mechanics
Identifiers
urn:nbn:se:ltu:diva-15541 (URN)10.1108/09615531111148464 (DOI)000296602900002 ()2-s2.0-79960254118 (Scopus ID)f1234d70-5b78-11df-ab16-000ea68e967b (Local ID)f1234d70-5b78-11df-ab16-000ea68e967b (Archive number)f1234d70-5b78-11df-ab16-000ea68e967b (OAI)
Note
Validerad; 2011; 20100509 (stlu)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Jonsén, P., Pålsson, B., Tano, K. & Berggren, A. (2010). Charge and structure behaviour in a tumbling mill (ed.). In: (Ed.), Antonio Munjiza (Ed.), The Fifth International Conference on Discrete Element Methods: Proceedings. Paper presented at International Conference on Discrete Element Methods : 25/08/2010 - 26/08/2010 (pp. 490-495). London: Research Publishing Services
Open this publication in new window or tab >>Charge and structure behaviour in a tumbling mill
2010 (English)In: The Fifth International Conference on Discrete Element Methods: Proceedings / [ed] Antonio Munjiza, London: Research Publishing Services, 2010, p. 490-495Conference paper, Published paper (Refereed)
Abstract [en]

The grinding process in tumbling mills is complex and to include all phenomena that occur in a single numerical model is today not possi-ble. This paper presents the results of a study in which the deflection of a lifter bar in a pilot ball mill is measured by an embedded strain gauge sensor and compared to deflections predicted from finite ele-ment (FE) simulations. The flexible rubber lifter and the lining in a tumbling mill are modelled with the finite element method (FEM) and the grinding medium modelled with the distinct element method (DEM). The deflection profile obtained from DEM-FE simulation shows a reasonably good correspondence to pilot mill measurements. The approach presented here is a contribution to the validation of DEM-FE simulations and an introduction to the description of a bend-able rubber lifter implemented in a DEM-FEM mill model. It opens up the possibility to predict contact forces for varying mill dimensions and liner combinations. FEM is especially valuable in this case, since there are readily available libraries with material models. This is a fol-low-up work to previous preliminary result from a mono-size ball charge interaction study

Place, publisher, year, edition, pages
London: Research Publishing Services, 2010
National Category
Applied Mechanics Metallurgy and Metallic Materials
Research subject
Solid Mechanics; Mineral Processing
Identifiers
urn:nbn:se:ltu:diva-35397 (URN)9eb59390-b690-11df-a707-000ea68e967b (Local ID)978-0-9551179-8-5 (ISBN)9eb59390-b690-11df-a707-000ea68e967b (Archive number)9eb59390-b690-11df-a707-000ea68e967b (OAI)
Conference
International Conference on Discrete Element Methods : 25/08/2010 - 26/08/2010
Note
Godkänd; 2010; 20110314 (ysko)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2018-02-28Bibliographically approved
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