Optimization of parameters affecting the filterability of the combined tailings of Gol-E-Gohar processing plant using filter press system

 
The prevention of water wastage in mineral processing plants, especially in desert and arid regions is the present and future serious priorities of this industry. To fulfil this goal, Gol-E-Gohar mining and industrial company has defined water recovery projects, including the investigation on the factors affecting the filterability of the tailings of magnetite and hematite processing plants using membrane chamber filter press. In this research, based on the literature review and given the limitations of the process, 10 factors including pH of the pulp, filter aid, flocculent, solid percentage of the pulp, filter medium, time and pressure of squeezing stage, time and pressure of air blowing stage, and finally chamber thickness were selected for investigation of their influence in three steps: initial experiments, one factor tests and designed experiments. It is found the effect of four factors are significant on the "final moisture" of cake including time and pressure of air blowing stage, solid percentage of the pulp and chamber thickness. Also, the major parameters affecting the "throughput" of filtration were defined as the time of air blowing stage, the chamber thickness, the time of squeezing stage, solid percentage of the pulp and interaction effect of the time of air blowing and squeezing stage and the interaction effect of the time of air blowing stage and solid percentage of the pulp. Finally, optimization of the factors based on three objectives was performed, obtaining the minimum moisture content of 14.32 %, the maximum throughput of 0.27 tons per hour per square meter, and a combination of 17% moisture and 0.147 tons per hour per square meter throughput when both moisture and throughput were optimized simultaneously. The optimized conditions were tested and verified in laboratory and pilot scale.