A Survey of the Production of Paste Tailing in Agh-Darreh gold beneficiation complex and its Environmental Impacts

Tailings from metal mining operations were conventionally disposed of as slurry in an engineered surface impoundment near a mine-mill complex. Such disposal can lead to a variety of environmental and other hazards, such as dust generation, dam failure, and leakage. Additional disadvantages may result from the requirement for large amounts of land with limited long-term beneficial use, as well as aesthetic impacts. Paste and thickened tailings technology is becoming recognized as an alternative for minimizing the engineering and environmental challenges commonly associated with the disposal of mineral wastes conventional tailings storage facilities. Paste is simply dewatered tailings with little or no water bleed that are non-segregating in nature. This paper focuses on some environmental and operational benefits associated with disposal of tailings in paste form.The environmental benefits of surface disposal of paste can be divided into two main categories; first, very little free water is available for generation of a leach ate, thereby reducing potential impacts on receiving waters and biological receptors. Second, the paste production technology allows for production of an engineered material by modifying the paste geochemistry in such a manner that environmental benefits result.Because of environmental risks related to gold beneficiation, a Paste Production and Storage Mechanism (PPSM) were installed in Agh-Darreh gold beneficiation complex. Research results are as follows: 34%reduction in tailing volume, 14% reduction in fresh water and required Sodium cyanide, 2 million U.S $ economic saving in construction of tailing dam, and decrease of environmental pollution of beneficiation complex.