Liu, P 2017, 'Technologies and practices of mechanized backfill mining for water protection with aeolian sand paste-like', in A Wu & R Jewell (eds), Paste 2017: Proceedings of the 20th International Seminar on Paste and Thickened Tailings
, University of Science and Technology Beijing, Beijing, pp. 284-293, https://doi.org/10.36487/ACG_rep/1752_32_Liu
Given the serious problem of Salawusu Formation Aquifer damage caused by caving mining in Yuyang Coal Mine, the technique of mechanized mining backfill with paste-like slurry using Aeolian sand was invented. The backfill used Aeolian sand as aggregate and alkali-activated fly ash as the cementing agent. The water-sand ratio was 1:1.3, with a mass concentration of 72%, and the initial fluidity of the filling slurry reached 210 mm. This paper proposes a calculation method for the local resistance loss of slurry transportation with pipeline, and the field gravity transport test results showed that the resistance loss of unit length elbow was 4.26 times as great as that along the path. Therefore, the pipeline diameter for the 14.9 lines of self-flowing was determined, and the pipeline flow design precision was improved by over 10%. The filling capacity reached 360 m3/h and the running energy consumption was low after adopting the filling station model of double pulping system and underground equipment pool. The paper also puts forward the method of whole filling space sealing with a cloth consumption being only 40% of that using the bag filling. Industrial test showed that the technique also protected water resources, based on the fact the filling rate was 98.5% in goaf, strata behavior slightly appeared, roof water leaching was less than 2 m3/d, and the surface subsidence value was 38 mm. Meanwhile, great breakthroughs have been achieved in lowering and improving production efficiency compared with similar technology.
Cui, F., Zhang, H.X. 2009, ‘Feasibility Analysis of Aeolian-sand for Underground Stowing’, Coal Mining Technology, vol. 14, no. 3, pp. 42-43,56.
Fan, L.M., Ma, X.D. and Ji, R.J. 2015, ‘Progress in engineering practice of water-preserved coal mining in western eco-environment frangible area’, Journal of China Coal Society, vol. 40, no. 8, pp. 1711-1717.
Feng, G.M., Sun, C.D., Wang, C.Z. and Zhou, Z. 2010, ‘Research on goaf filling methods with super high water material’, Journal of China Coal Society, vol. 35, no. 12, pp. 1963-1968.
Fu, Y., Xie, Y. and Liu, D.K. 2003, ‘New technology test of self flowing filling slurry pipeline’, Nonferrous Metal, vol. 55, no. 5, pp. 8-11.
Hu, B.N. 2012, ‘Backfill Mining Technology and Development Tendency in China Coal Mine’, Coal Science and Technology, vol. 40, no. 11, pp. 15-18.
Jiang, J.H. 2012, ‘Study on preparation, structures and properties of mine backfill materials from mud solidification’, Hunan University of Science and Technology.
Liu, J.G. and Zhao, L.T. 2014, ‘Theory of water protection and practice application in mining based on the backfilling mining technology’, Journal of China Coal Society, vol. 39, no. 8, pp. 1545-1551.
Lu, Y.Z. 2006, ‘Study on the movement law of overlying strata under the control of coal gangue paste filling method’, Central South University.
Miao, X.X. 2012, ‘Progress of fully mechanized mining with solid backfilling technology’, Journal of China Coal Society, vol. 37, no. 8, pp. 1247-1255.
Qiu, M., Shi, L.Q., Yu, X.G., Gao, W.F. and Shi, Y.K. 2016, ‘On preventing the high pressure water-inrush from floor with paste-like backfill mining’, Journal of Mining & Safety Engineering, vol. 33, no. 3, pp. 409-414,422.
Sun, A.G. and Yang, Y.W. 2015, ‘The practice of backfilling mining under aquifer in Wu gou Coal Mine’, Energy Technology and Management, vol. 40, no. 6, pp. 105-107.
Sun, K.H. 2014, ‘Experimental research on Aeolian sand paste-like stowing material for mine’, Coal Technology, vol. 33, no. 5, pp. 262-265.
Sun, K.H., Liu, P.L. and Sun, W.M. 2016, ‘Research and application on Aeolian sand paste-like stowing material for mine’, Metal Mine, vol. 4, pp. 172-176.
Wang, X.D. 2016, ‘Relationship between engineering performance and mix proportion of fly ash for cemented and high concentration backfill material with wind blown sand as aggregate’, Journal of Engineering Geology, vol. 24, no. 1, pp. 78-86.
Xia, Y.C., Du, R.J., Sun, X.Y. and Du, X.H. 2016, ‘Countermeasure of ecologic phreatic water protection and mine water disaster prevention in northern Shanxi Coalfield’, Coal Science & Technology, vol. 44, no. 8, pp. 39-45．
Yan, S.H., Liu, Q.M., Zhang, H.X. and Wang, H.X. 2008, ‘Backfill mining technology for gateway and pillar top coal caving mining under aquifer of shallow thin bedrock’, Coal Science and Technology, vol. 36, no. 1, pp. 1-3,14.
Zhang, J.W., Ni, W., Hu, W. and Huang, X.Y. 2013, ‘Research on the fluidity of backfilling material with preparation of steel slag gel system’, Metal Mine, vol. 443, no. 5, pp. 153-156,168.
Zhang, J.X., Li, M., Deng, X.J. and Li, J. 2014, ‘Method and application of extending mining upper limit under aquifer by gangue backfill mining’, Journal of Mining & Safety Engineering, vol. 31, no. 2, pp. 220-225.