Optimum Material Proportion And Transportion Parameter Of Multiphase Complex Paste Backfill

Paste filling slurry owns the obvious merits, such as good steady, no eduction, needless dehydration in stope, low filling cost, and so on, so paste backfill technology is attentive by prospector, and widely applied in mines in the world. Based on deep safe mining, environment protection and improving resource recovery, a filling technology of multiphase complex materials that mix by total tailings and smelted lead slag is applying in Huize Lead-zinc Mine in Yunnan province. At present, the researching fruits of paste backfill parameters about constitutive materials and transportation are only solely adapted classed tailings, total tailings, gravel, et al, so they cannot apply directly in designing backfill system of multiphase complex materials of total-tailings and lead slag. Therefore, a series researches, such as the gelating characters of total tailings and lead slag, mechanical-chemic effect of paste slurry, the testing flat of pipe transportation and engineering technologies of paste slurry preparation and transportation, are carred through. So the reasonable ratios of filling materials and optimal transporting parameters are obtained, and a engineering paradigm that realize paste filling with materials of total tailings and lead slag applying in Huize Lead-zinc Mine is set up.The main contents of this paper are included as follows.(1) The testing results of material characters show that fine granularity are excessive in total tailings and less in lead slag, and there are complementarity between them in granularity distributing, so the normative paste filling slurry can be produced when they are mixed. Experiments show that multiphase-complex paste slurry composed by total tailings and lead slag materials owns the characters of good steady, plasticity, liquidity and strength, at the same time, the paste filling slurry can be mix by mill waste water and not be influence in strength of backfill.(2) The experimental characters of paste filling material show that total tailings is dolomite, and melted lead slag is multiphase-glass fusing body, so the solidification and strength of paste backfill are lower. If a material of Ca(OH)2 is appended, paste filling material can be solidifiable, but their indexes of long term strength are influenced, so the material of Ca(OH)2 can not be activator as multiphase-complex paste materials of total tailings and smelted lead slag.(3) After exploring and experimenting mechanical-chemic mechanism of multiphase-complex paste slurry of total tailings and lead slag, the functionaries of mechanical activation to paste material are obtained, and the problems of no solidification and low strength are solved. Through the mechanical-chemic action of high power beater to paste slurry, the gelatification of fine granule tailings can be excitated, and the exterior and configuration of lead slag can be breakaged, so the hydrolysates of cement are rapid, at the same time, the solidification and strength of paste backfill can be improved. The experiments show that the paste slurry churning by mechanical-chemic mechanism owns better characters of rheology, subsiding value, denseness, stability, plasticity and fluidness.(4) A pumping test platform of full-size ring pipe was developed to test transportation parameters of multiphase-complex paste slurry of total tailings and lead slag materials for Huize Lead-zinc Mine, and through experiment, the transmission parameters of the different proportion of paste materials were obtained. Based on gray theory, the gray correlation sequences of influencing factors to pipe flow resistance are determined, and the conclusion that the concentration and transportation flow of filling slurry are decisive influence factors is obtained. Experimental studies found that pipe flow resistance is proportional linear relationship with the distribution along the flow (or velocity), and pipe flow resistance is proportional linear relationship & a power relation with tube filling material concentration.(5) Based on experiment of multi-diameter annular pipe, transporting resistance formulas of diversified paste slurry are obtained, and the Huize formulas of transporting resistance are gained by the condition of 150mm diameter, at the same time, the adaptability of Huize formulas are verified and proved.(6) The researches show that the multiphase-complex paste slurry owns rheology character of viscidity and plasticity, and the rheology model is Bingham model that is no Newton liquid. By transporting resistance experiment of multi-diameter annular pipe and L figure pipe, the rheologcal parameters ofτ0 andηare analyzed. The summarized laws show that initial yield stressesτ0 of pipe transportation increase with the enhancing of concentration, minish with increasing content of cement in the condition of lower cement content, and increase with increaser content of cement in the other condition.(7) Adopting a method of neural network, a non-linear perplexing model that embodies the relationships between resistances of pipe transportation and concentration of slurry, flux, content of cement and content of total tailings is set up, and the inherence laws between transporting resistances and their influencing factors are revealed. At the same time, with a method of chaotic optimization, the optimal transporting parameters of multiphase-complex backfill of total tailings and smelted lead slag are obtained.(8) The engineering technologies of preparation and transportation of multiphase complex paste are researched, and the paste filing system of total tailings and lead slag in Huize Lead-zinc Mine is designed. The equipments, such as sedimentation and dehydration of tailings, continuing preparation and imbursement of tailings paste slurry(PCP & SM), high power blender of type STF-700(Ⅰ) based on theory of mechanical-chemic mechanism, et al, are innovated, and a engineering paradigm that realizes paste backfill applying in Huize Lead-zinc Mine is set up.