| The effective contact occurred between ores and solution is the critical premise of the realization of ore leaching. Based on the theory of solid-liquid interaction in the leaching system, the paper used surfactant as the technical means to strengthen leaching of copper ore in order to realize the purpose of improving the permeability of heap and the efficiency of ore leaching. The research work could be summarized as follows:(1) A thermodynamic model of solid-liquid connecting effects between solution and ores was constructed. In addition, the energy equation of solid-liquid effect between solution and ore solid-liquid under different conditions was established.Thus, it obtained the critical factor that affects the connection of ores and solution. The influence of different factors on solid-liquid connecting effect was analyzed as well.(2) The surfactant selection and optimization of leaching experiment conditions were completed. Also, an indicator named "assistant leaching attenuation coefficient of surfactant" was proposed for the first time and it was applied to evaluate the persistence of surfactant’s assistant leaching effect. Based on PB experiment, significant factors, which influence leaching rate, were obtained. The assistant leaching experimental conditions mixed with surfactants were optimized by response surface experiments.(3) The response characteristics of ore wetting properties on surfactant were investigated. The wetting performance experiment of ore surface was carried out, having revealed the wetting properties of solution mixed with surfactant on the ore surface as a result. Besides, a mathematical model, which is named "the real contact angle" on the ore surface in leaching reactions under the existence of surfactants, was constructed firstly. The evolution of roughness and wettability of ore surface were also ascertained in the leaching process.(4) The capillary rise experiments and column leaching experiments were carried out under the condition of different concentration of surfactants. The relationship among the capillary attraction, capillary rise height and surfactant concentration was ascertained. The influence of surfactants on pillar permeability and ore leaching rate was also obtained. The results showed that the pillar permeability increased by twice times, as well as the ore leaching rate increasing by 8.4%.(5) The functional mechanism, that is, surfactants strengthen ore leaching, was revealed. Additionally, the interaction between adsorption characteristics and leaching reaction of surfactants was analyzed. The mechanism that surfactant strengthens solution seepage in heaps was ascertained and the influence of surfactants on ore leaching rate was obtained as well.(6) The effect of surfactants on the solute transport and solution seepage was simulated. Based on the numerical simulation analysis method, the visualization of flow rate variation, ion concentration distribution and evolution of leaching rate was achieved. The law of solute transfers and solution seepage was obtained under the condition of different concentration of surfactants.(7) A vision that the surfactant was applied to heap leaching production was proposed, as well as the preparation and addition processes of surfactant solution were designed. What’s more, the effect of surfactants on the leaching subsequent process was discussed such as metal extraction and the biodegradation characteristics of surfactants were investigated as well,... |
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