Possibilities of Exploitation of Bauxite Residue from Alumina Production

Abstract

The world aluminium production was 31.9 million tons in 2005 (Hetherington et al., 2007)\r\rand the demand is still growing. Aluminium is obtained from aluminium ore called bauxite\r\rin compliance with the locality where it was found near Les Baux in southern France in\r\r1821. Bauxite can be found on all the continents, except for Antarctica, while the most\r\rabundant deposits are situated in tropical and subtropical zones, which provide optimal\r\rclimatic conditions to its formation (Bardossy, 1990).\r\rFrom ecological point of view the most significant world problem in aluminium production\r\ris creation of considerable amount of insoluble bauxite residue (BR). It is waste that, due to\r\rway of its production, is determined as red mud (RM) or brown mud (BM). 1 t of produced\r\raluminium gets 2 t of waste and it is estimated that nowadays, during the bauxite\r\rprocessing, 120 million t of BR is produced worldwide (Red Mud Project, 2011).\r\rEven if there is all-out effort in the world to reuse the waste from the aluminium production\r\r(Paramguru, 2005; Snars & Gilkes 2009; Liu et al., 2011; Maddocks et al., 2004), its majority\r\rpart is dumped and due to its dangerous properties (high pH value, strong alkalinity,\r\rincreased content of radioactive substances etc.) it is a significant environmental burden\r\rnow and it will be a load also in the future. All world aluminium producers try to solve\r\rabove mentioned problem more or less successfully. In this chapter, we propose a brief\r\roverview of the most significant possibilities of waste mud exploitation together with\r\rassessment of possible influence on the environment based on ecotoxicity tests.