利用脱硫灰渣和粉煤灰开发充填胶凝材料及在金川矿山应用

Research on a New Cementitious Materials Based on Desulphurization Ash and Fly Ash and Its Application in Jinchuan Mine

为了降低充填采矿成本,在固结粉胶凝材料开发的基础上,本文利用脱硫灰渣和粉煤灰废弃物资源,开发棒磨砂粗骨料充填胶凝材料。首先对棒磨砂骨料进行粒径级配分析。分析结果表明:棒磨砂含泥量(-75μm)小于8%,满足棒磨砂骨料规定的含泥量,但+3.2 mm颗粒粒度含量大于3%,粗颗粒含量较多;然后开展料浆浓度78%,胶砂比1:4棒磨砂胶结充填体强度正交试验,由此获得胶凝材料配方为:生石灰3%、脱硫灰渣18%、粉煤灰15%、芒硝5%、NaOH1.5%、矿渣微粉57.5%,其胶结充填体3 d、7 d、28 d强度分别达到1.57 MPa、3.64 MPa、7.12 MPa,满足胶结充填体强度要求。研究结果显示,芒硝和NaOH对胶结充填体早强作用明显,但芒硝对后期强度增长不利,而NaOH对后期强度影响不显著。在物料协同作用下,粉煤灰和脱硫灰渣对充填体早期强度增长不利,脱硫灰渣有助于充填体后期强度增长;粉煤灰对28d强度影响呈现下降趋势;同时粉煤灰有助于提高充填接顶率。该充填胶凝材料已经在金川龙首矿应用,由此获得显著的经济效益和环保效益。

In order to reduce the cost of filling mining, on the basis of the development of the earlier consolidated powder cementitious material, using the potential activity of the desulphurization ash and fly ash solid waste resources, a new cementitious material suitable for filling the coarse aggregate of the bar grind is developed. In this paper, the particle size of the sanding aggregate is tested at first. The results show that the mud content (-0.08 mm) of the bar grit is less than 8%, which satisfies the mud content stipulated in the technical conditions, but the particle size content of the +3.2 mm particles is greater than 3%, and the content of coarse particles is more. Then the concentration of filling slurry is 78%, and the ratio of the mortar to sand is made. The strength test of coarse aggregate cementation of 1:4 is tested. Through orthogonal exploration, optimization and test, the formula of cementitious material is: Lime 3%, desulphurization ash 18%, fly ash 15%, mirabilite 5%, NaOH1.5%, and slag powder 57.5%, the strength of 3 d, 7 d and 28 d age of cemented filling body are 1.57 MPa, 3.64 MPa, 7.12 MPa, respectively. It can meet the requirements of mine filling. Through this experiment, it is found that the effect of Glauber's salt and NaOH on early strength of filling body is obvious, mirabilite is unfavorable to the post strength growth of the filling body, and the effect of NaOH on the late strength of the filling body is very little;under the synergistic action of material, the fly ash and desulphurizing ash are unfavorable to the early strength of the filling body, and the desulfurization is disadvantageous. Ash can help to increase the strength of the filling body at the later stage;the effect of fly ash on the strength of 28 d presents a downward trend;at the same time, the fly ash can help to improve the filling rate.The filling cementitious material has been applied in longshou mine of Jinchuan mine.