THE USE OF SURFACE MINER AT PARAGOMINAS BAUXITE MINE

Edil Neto Pimentel, Joel Souza, Fabio Trindade Pereira, Ronan Candido Mendes, Agnus Dei Delgado

The Paragominas bauxite mine is located in the north of Brazil and has about 280 millions metric tons of washed bauxite (dry). The average ore thickness is about 1.5m and after the overburden removal the ore is ripped by bulldozer (34m3), excavated by backhoe hydraulic excavator (5m3) and loaded to small trucks (25m3). In order to get better selectivity and reduce the costs on the mining process, Mineração Paragominas has bought a surface miner. This equipment has replaced the operations did by the bulldozers, hydraulic excavators and the graders. Beyond this, it has almost the double of the hydraulic excavator productivity and can work with bigger trucks (60m3) reducing the mining costs. The ore control process is better, since the terrain shape left by the surface miner is more regular. At the feasibility studies there were a lot of questions and doubts regarding the performance and costs of this machine. The first question was about the productivity working on the bauxite of Paragominas mine which is very hard, when compared with MRN for example. The second question was about the costs, since the bits consumption has a big weight on the operation costs. And the last one was about the operation on the rainy seasons since with the backhoe excavator always works on the top of the ore and with the surface miner there are three or four levels depending on the ore thickness. This paper discusses these questions and presents the previous results of the performance of this machine.