Study On Thickness Law And Rheological Properties Of Tailings Slurry Under Ultrasonic

Based on the National Natural Science Foundation of China" The mechanical characteristics of tailings slurry under acoustic/ultrasonic action",in view of the difficult problem of solid-liquid separation of vertical sand slurry tailings slurry at present,in order to speed up the dense settlement of tailings and improve the fluidity of slurry,improve the filling ability of vertical sand silo and reduce the backfilling cost,this paper through the theoretical research,physical experiment,numerical simulation and other means carried out the study on the thickening regularity and fluidity improvement of tailings slurry under the action of ultrasonic,it mainly includes the following parts:(1)Based on the theoretical research,this paper introduces the type and physical properties of ultrasonic,expounds the characteristics of ultrasonic,reveals the mechanical action mechanism between the external acoustic field and tailings particles,and establishes the propagation equation of ultrasonic in the tailings slurry,at the same time,studied the pointing characteristics of ultrasonic transducer at different frequencies,and laid theoretical foundation for the selection and application of ultrasonic wave.(2)Through the laboratory test,the ultrasonic wave of different frequency is applied to the tailings slurry after different settling time,and the ultrasonic wave of different power is applied after the fixed settling time,it studied the response law of ultrasonic wave to the dense settlement of tailings slurry,and analyzed the phenomenon in the process of ultrasonic wave,finally,established the prediction model of the final quality concentration of the tailings slurry under the action of ultrasonic by response surface method.(3)To simulate the sand-sand settling environment in the sand bin model,measured the changes of sand concentration in sand silo before and after the application of ultrasonic field and the quantity of different ultrasonic transducers.Studied the improvement of the phenomenon of the tailings plate junction in the sand silo by ultrasonic wave.(4)The heological properties of the slurry and the tailings slurry were tested under the ultrasonic wave,through the analysis of the experimental data,analyzed the improvement laws of the plastic viscosity and yield stress of the rheological parameters of high concentration pulp by the ash and sand ration,concentration,ultrasonic power and frequency.The viscosity and yield stress of backfill slurry and tailings slurry decrease with the increase of ultrasonic power.Collated rheological test data,with the support vector machine,established the rheological parameter prediction model of slurry by LibSVM,and predicted the rheological parameters of high concentration slurry under ultrasonic wave.(5)Theoretically analyzed the mechanism of ultrasonic attenuation in slurry,and established the theoretical model of ultrasonic attenuation in slurry under the condition of mixed particle size,subsequently,studied the effect of tailings concentration and particle size on the attenuation of ultrasonic in slurry through the experimental method and theoretical results.(6)Using the Comsol Multiphysics numerical simulation software,according to the established ultrasonic wave propagation model in the tailings slurry,by changing the frequency of ultrasonic,the number of ultrasonic transducer and the array mode of transducer,etc,the acoustic pressure propagation characteristics of ultrasonic in the tailings slurry were numerically simulated,and studied the propagation law of ultrasonic in the tailings slurry,optimized the arrangement mode of ultrasonic transducer,which laid the foundation for the installation and application of ultrasonic in the sand silo.