Mine Gob Paste Filling Theory And Technology Research

Cemented backfilling technology is an effectual mining technology under thedeep, complex, especial deposit, which was more than half century that go throughlow-concentration concrete cemented backfilling, low-concentration tailing cementedbackfilling, tailing high-concentration cemented backfilling, high water quick settingtailing cemented backfilling. Aiming at paste backfilling of underground Open-stope,this paper put up systematic and deep research to theory and technology. Maincontents and main conclusions of this paper are summarized as follows:(1) Characteristics of paste slurry are opened out at aspects of density, yieldstress, flow curves, pumping-suitability and so on. Paste slurry hasn't evidentdensity-gradient and velocity-gradient. It's non-Newton slurry, close to Binham-slurryof structure-flow.(2) Calm-transportation, high backfilling quality and good economic effect isguaranteed by optimal paste slurry ratio, innovation of backfilling materials andapplication of chemical additives.(3) Energy release rate of surrounding rocks and average stress of pillars can beeffectively reduced by filling body in deep mines. Collapse risk of surrounding rockscan be forecast by energy calculated according to risk forecasting model in the viewof energy control. The forecasting method supplies an effective means to evaluatesafety of deep mining and establishes an important theoretical base of design andchoice of deep stope structure, filling materials and filling systems.(4) Adaptabilities of several alternative filling systems to deep mines areanalyzed. Studies about calculation of slurry density corresponding to critical flowregime and transforming measures of flow regime prove that paste gravity flowtransportation will be the most suitable deep filling systems worth popularizing inChinese deep mines.(5) Impacting mechanism of free fall slurry to deep vertical pipe is clarified, andmovement model of slurry within vertical pipeline is developed. Whole pipe flowtransportation system adapt to deep mines because of low pipe wear and low pipepressure.(6) It is approved by relational study between initial conditions and resistanceloss values that the latter increases with increasing length of pipe, and entrance velocity, unit weight and effective viscosity of slurry, but decreases with increasingpipeline diameter. Resistance loss value simulated by ANSYS FLOTRAN CFD modelconforms nicely to the backfilling practices, suggesting that ANSYS FLOTRAN CFDis a fast and effective means calculating the resistance loss of pipeline transportationsystem. It is believed that approach employed in this paper could give a valuablereference for related mines.