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| Author(s): |
Fábio Augusto da Silva Salvador
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2001-11-09 |
| Examining board members: |
Lineu Azuaga Ayres da Silva;
Jorge Hachiro;
Henrique Kahn;
Pedro Kunihiko Kiyohara;
Lindolfo Soares
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| Advisor: | Helmut Born |
| Abstract | |
Pyrobituminous oil shales from the Irati Subgroup of the Paraná Basin are being mined by PETROBRAS and processed by the PETROSIX technology in semi-industrial scale at São Mateus do Sul, Paraná State, Brazil, since 1972. Two sub-horizontal shale layers, 6 m and 2.5 m thick, separated by limestone and siltstone beds, are being mined in a 65 km2 area by open pit methods. Oil, gas, sulfur and several other clay by-products are obtained. Immediately after soil and overburden are removed, the shales undergo a rapid degradation process, mainly splintering and fracturing, which result in significant amounts of fine particles during blasting, crushing, drying and handling stages. As particles under 11 mm can not be fed to the retorts, the elimination of the fine fraction which sometimes amounts to about 20% of the material, results in significant oil losses. This fraction, however, may be employed for energetic purposes in other facilities, and possibly for other uses, as ceramics. The causes of the physical decay of the shales have never been investigated in detail. This contribution presents the results of mineralogical, geological and terrain morphology studies in the mine to explain the causes and mechanisms involved in fine particles generation, which will be of practical use for mine planning purposes in new oil shale extraction areas. (AU) | |