Mineral paste production from phosphate rock tailings

Abstract

The dewatering stage is among the most important industrial unit operations, and is widely adopted in many different industries. Nowadays, mineral processing tailings disposal is a big problem due to the environmental degradation it causes. The phosphate rock processing in Anglo American Phosphate Brazil, situated in Catalão/ Go/Brazil, generates around 180 t/h of tailings for a plant feed of 480 t/h (approximately 37.5% of the processing plant feed), with 5 to 10% of solids and approximately 14% of P2O5. Nowadays, the tailings are sent directly to the tailings dam. The present work proposes paste production using the tailings from the phosphate rock processing plant. Through decantation of a tailings sample, a clarified liquid was obtained and drained. The decanted pulp then went through a second stage consisting of vacuum filtration. Flocculant addition in this stage generated a faster sedimentation rate and a higher dewatering performance in next stage of dewatering, because the flocculated material was retained by the filter medium instead of passing through it. The results were satisfactory for paste tailings production with a solid percentage of around 65%.

Uso De Surfatante Na Filtração De Rejeito Fosfático

“…Semelhante aos resultados anteriores, os ensaios com o pH 6 são significativamente mais satisfatórios quando comparados aos ensaios realizados com a polpa em pH natural (7,5). Percebe-se também que a taxa unitária de filtragem foi maior (0,0076 t/h/m²) em pH 6 contraposto a uma TUF de 0,055 t/h/m² em pH natural, apontando que a produtividade do processo de filtração de rejeito fosfático é maximizada utilizando o menor valor de pH.…”

“…A pressão da população tal como as preocupações ambientais dificultam o licenciamento de áreas para a construção de barragens e, além disso, esses depósitos contam com um alto custo de monitoramento. Uma alternativa viável pode ser a deposição dos rejeitos em forma de pilhas, nesse processo a polpa antecipadamente adensada poderia ser filtrada e a torta proveniente dessa filtração disposta em pilhas, até mesmo junto com o estéril da mina (SILVA et al, 2015;GUIMARÃES et al, 2012).…”

Modeling and Simulation of Hydroxyapatite Recovery in the Desliming Circuit of the Tapira Industrial Plant, Brazil

“…This combination results in the need to control each stage of an industrial desliming circuit to balance the benefits and losses of hydroxyapatite (HA) from the process. This last aspect is critical as slimes are diverted to tailings dams, which either reduces the life of these structures or increases the mass to be dewatered and piled up in high-cost operations, as recently occurring in Brazilian mining [5][6][7].…”