| The 13th Five-Year Plan for Ecological and Environmental Protection of the State proposed to promote the implementation of tailings filling mining technology,the construction of a number of "tailless mines",tailings for filling and comprehensive utilization,out of a green mining and environmental protection coordinated mining development road.It can be seen that filling is the main direction of mining development,many mines at home and abroad began to transition to the direction of filling mining.In view of the high production rate of gold mine tailings and the fine particle size of tailings,it is the best way to treat tailings and realize the construction of tailless mine by using fine particle tailings goaf filling and coarse-particle tailings as building materials.Obviously,in order to realize high concentration filling of low concentration fine tailings or ultrafine tailings in concentrator,dense flocculation and settlement of ultrafine tailings is the key technology.Therefore,this paper focuses on the thickening of ultrafine tailings.Theoretical analysis,physical test and numerical simulation are used to study the characteristics of flocculation settlement and thickening technology.Finally,the technology is applied to engineering practice.The research achievements of this paper are as follows:(1)On the physicochemical properties and mesoscopic structure of ultrafine backfilling and quantitative characterization of parameterization,determine the"superfine backfilling" gradation selection range,analyzing the characteristic of the superfine backfilling macroscopic and mesoscopic mechanics parameters of the intrinsic connection mechanism,superfine backfilling sedimentary characteristics and seepage mechanism,a comprehensive study of ultrafine backfilling medium medium characteristics as a whole.(2)Backfilling materials with ultrafine for selected object to carry out the hydrocyclone classification efficient screening test,as conditions of thick material selection,optimization,from the fluid particles energy equation,free vortex motion equation and the analysis of forced vortex motion equation optimal selection particle impact on thick,validation under the condition of stable mass concentration,pressurematerial diversion ratio and the concentration-the overflow of the relationship between split ratio,RSM and Mixture models were used for numerical analysis of particle phase and simulation of particle trajectory to demonstrate the effectiveness of the screening method.(3)Static and dynamic flocculation and sedimentation tests of ultrafine tailings were carried out to study the evolution law and flocculation mechanism of ultrafine tailings from granular particles to flocs structure,quantitatively characterize the relationship between particle microstructure and flocs structure,and reconstruct the development process of spatial structure of flocs using SEM scanning,nuclear magnetism and Interactive 3D Plot.The sedimentation evolution behavior of superfine tailings was comprehensively mastered,and the flocculation sedimentation particle model(MPM)was established to quantitatively describe the sedimentation process of superfine tailings.(4)Structures,superfine backfilling thick physics experimental test platform,the whole process to carry out the dynamic shock experiment simulation,considering many factors coupling analysis of slurry under the condition of solid-liquid separation and sedimentation characteristics influence law of the underflow concentration of backfilling in free sedimentation interference settling the whole process of compression settlement under the coupled action of solid-liquid two-phase mechanical characteristics and to study the migration behavior,A dense mathematical model of multi-factor condition correlation is established.(5)According to the fluid dynamics theory,flocculation dynamics simulation method was used to optimize the process parameters,and similar simulation tests were carried out to determine the optimal three-dimensional multi-zone settlement dense structure.CFD FLUENT software was used to establish a large scale numerical model of ultrafine tailings thickening,and the spatial-temporal evolution characteristics of the model flow field(pressure,tailings concentration,flow rate,turbulent kinetic energy and turbulent viscosity)were presented.The operation parameters of ultrafine tailings in the thickening machine were compared and analyzed,and the industrial operation effect was in line with the expected goal.(6)Using ANSYS finite element software to carry out the thickener modeling unit strength and stability analysis of body structure,backfilling is given special equipment manufacturing oriented knowledge in the field of engineering design requirements,knowledge acquisition were analyzed from the point of view of knowledge engineering,description and application for ultrafine backfilling thick system reliability,based on theoretical derivation and industrial application of dense technology solutions. |
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