Aplicação de tomografia computadorizada de raios-x para estudo do sistema de cleats de carvão da jazida de Leão-Butiá, na Mina do Leão II, RS

摘要

The global warming, due to the accumulation of greenhouse gases (GHG) emissions in the atmosphere, has been producing an increase in global mean temperature and by the large engineering projects, intended to reduce and stabilize the concentration of GHG in the atmosphere, especially CO2. Among the seven key technologies for reducing GHG emissions is the carbon capture and storage (CCS), which consists in capture, transport and storage CO2 in geological media, for example, saline aquifers, oil and gas fields and non-mineable coal seams. The latter to be the object of the present study was detailed and the procedures adopted for the analysis in coal seams consist of scanning two samples of Brazilian coal by means of X-ray computed tomography images to obtain two-dimensional system containing the cleats and better understand the gas flow in the layers. This tool is being tested for the first time in coals of Brazil and it’s fundamental to understanding the development of projects of Coalbed Methane (CBM) and Enhanced Coalbed Methane (ECBM) in the county, that is still an unknow potencial, wich could increase the demand for natural gas in the regional energy supply. From this work it was concluded that the cleats of coal samples studied are easily identified and it is possible to extract relevant data about orientation, spacing, length and volume of cleats per area. The cleats of the coals studied, however, are very small compared with data from foreign literature, are also filled with calcium carbonate, which hinders the CO2 and CH4 flow in the coal seam and reduces the permeability unfeasible to implement projects of geological storage of CO2 in the coal seam from this study.