Mineralogi och magnetiska anrikningsegenskaper hos Småland Tabergs Fe-Ti-förekomst
Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
Smålands Taberg's Fe-Ti occurence is situated ca 10 km south of Jönköping in the city of Taberg, Jönköping county, southern Sweden. It is a peculiar deposit both geographical and geological, it forms a massive body which rises 140 m above the surrounding terrain as a massive mountain. The mountain consists of titanomagnetite-olivinite and contains titanium, iron and olivine. The occurence is situated in the geological protogine zone and is assumed to be an early crystallisation product of a basaltic magma which intruded the surrounding rock for 1.2 billion years ago. This works purpose was to investigate the mineralogical composition of the occurence towards the depth and to enrich the ore into three different fractions: 1) one Fe-rich, Ti-olivine poor concentrate, 2) one Ti-rich, Fe-olivine poor concentrate and 3) one olivine, Ti-Fe poor concentrate. The samples were collected from the surface and from a uniqe drillhole prooving that the ore continues from 240 m revealing an utterly homogeneous mineralogical composition with 20-35 % anhedral titanomagnetite and 30-45 % subhedral grains of olivine in almost every examined sample. Other common minerals in the studied samples are euhedral to subhedral labradorite, pargasite forming coronas around labradorite and serpentine replacing olivine in so called marsh structure. Locally subhedral grains of apatite appear in the larger serpentine fissures. Lamellae of both ilmenite and hercynite are common and present in all observed grains of titanomagnetite. Seldom is the cloth like texture of ulvöspinel found in the titanomagnetite. The sulphides pyrrhotite, pyrite, chalcopyrite and pentlandite are observed as small grains in most of the samples. Detailed studies in a scanning electron microprobe confirmes the homogeneous composition towards depth with an average iron content of 70 %, titanium of 4 % and vanadium of 0,7 % in the titanomagnetite. A peculiar discovery regarding the mineralogy is the platinum content of up to 3 % in grains of apatite.For an assesment of the beneficiation properties the grain sizes of the identified minerals were measured showing a homogeneous size distribution towards depth. Grain sizes of the minerals present showed that titanomagnetite varies between 50 – 800 µm and lamellae of ilmenite between 0,1 – 10 µm. Grains of olivine is generally larger, between 50 – 1100 µm while the euhedral labradorite accounted for the largest mineral present with sizes between 100 µm – 1,5 cm. The few grains of sulphides present is small, sizing between 10 – 45 µm.Three LIMS beneficiation tests were performed on the ore, ground to 95 % <63 µm. The ore and the two products were analysed in the SEM containing the following: Ground ore with 32,13 % Fe, 5,41 % Ti and 0,31 % V. Magnetic concentrate with 56,8 % Fe, 10,15 % Ti and 0,6 % V, yielding 60,38 % Fe, 64,11 % Ti and 66,11 % V and non-magnetics with 23,61 % Fe, 2,79 % Ti and 0,09 % V. 13 HGMS tests were performed on the non-magnetic fraction from the LIMS test with the purpose to enrich ilmenite. Ti-grades between 3,53 % to 5,73 % with yields of 64,26 % and 96,59 % respectively were achieved. Due to the magnetic properties of olivine the Ti-grades in the magnetic fraction were unsatisfactory. The contents and yields for Ti indicates that full liberation is not achieved and that another grinding step or beneficiation strategy is necessary for better yields. The purpose of the work was not entirely achieved, although it proved that a Fe-Ti-V-rich, olivine poor fraction can be created after a LIMS enrichement.
Place, publisher, year, edition, pages
2015. , 75 p.
Teknik, Smålands Taberg, SEM analys, våt lågintensitets magnetseparering, kornstorleksfördelning, malningsundersökning, stångkvarn, homogen malmkropp, plagioklasrik Fe-Ti malm, protogena zonen, platina, vanadin, olivin, titanomagnetit, titanomagnetitolivinit
IdentifiersURN: urn:nbn:se:ltu:diva-53673Local ID: aaca5873-35fc-4897-b5bf-d8e3fd107caaOAI: oai:DiVA.org:ltu-53673DiVA: diva2:1027049
Subject / course
Student thesis, at least 15 credits
Mining and Geotechnical Engineering, bachelor's level
Validerat; 20150819 (global_studentproject_submitter)2016-10-042016-10-04Bibliographically approved